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Adaptive Mechanisms of Tumor Therapy Resistance Driven by Tumor Microenvironment

Peijie Wu, Wei Gao, Miao Su and 4 more

Frontiers in Cell and Developmental Biology · 2021 · Review · CC BY

doi:10.3389/fcell.2021.641469

Abstract

Cancer is a disease which frequently has a poor prognosis. Although multiple therapeutic strategies have been developed for various cancers, including chemotherapy, radiotherapy, and immunotherapy, resistance to these treatments frequently impedes the clinical outcomes. Besides the active resistance driven by genetic and epigenetic alterations in tumor cells, the tumor microenvironment (TME) has also been reported to be a crucial regulator in tumorigenesis, progression, and resistance. Here, we propose that the adaptive mechanisms of tumor resistance are closely connected with the TME rather than depending on non-cell-autonomous changes in response to clinical treatment. Although the comprehensive understanding of adaptive mechanisms driven by the TME need further investigation to fully elucidate the mechanisms of tumor therapeutic resistance, many clinical treatments targeting the TME have been successful. In this review, we report on recent advances concerning the molecular events and important factors involved in the TME, particularly focusing on the contributions of the TME to adaptive resistance, and provide insights into potential therapeutic methods or translational medicine targeting the TME to overcome resistance to therapy in clinical treatment.

Full text

From PubMed Central, U.S. National Library of Medicine, as current on Oct 22, 2026. Paragraph numbers are ours, so an answer can point at one.

Introduction

Cancer is a significant public health problem worldwide, with substantial incidence and mortality rates. There have been spectacular advances in the development and therapeutic application of treatment for tumors, including chemotherapy, radiotherapy, targeted therapy, and immunotherapy over the past several decades. However, resistance to these therapies has been a major obstacle that restricts the effectiveness of cancer treatments and impacts patient survival. Therefore, most patients respond to therapies at an early stage, whereas patients at a later stage frequently display poor clinical outcomes with continuous treatment. A broad range of intrinsic mechanisms underlying how cancer cells escape from the cytotoxicity of tumor therapies have been revealed, including decreased drug accumulation, altered drug metabolism, mutated or altered drug target and enhanced DNA repair capability, as well as inactivated cell death signaling. Tumor cell heterogeneity, especially cancer stem-like cells (CSCs), is another cause leading to various resistance responses for multiple therapies. Accordingly, multiple studies have addressed intracellular response, including genetic or epigenetic alterations, for cell survival under the death pressure induced by therapies. New viewpoints and theories have proposed that tumor progression, especially when confronted with external pressure from various therapies, is a dynamic and complicated process that tightly interacts with the surrounding environment.

The tumor microenvironment (TME) is the extracellular environment in which tumors cells exist, and consists of carcinogenetic cells, cancer-associated fibroblast (CAFs), immune cells [including T and B lymphocytes, tumor-associated macrophages (TAMs), and natural killer cells], the vasculature system, and the extracellular matrix (ECM; including secreted cytokine, chemokine, metabolites, and exosomes). It has been shown that the non-malignant cells in the TME are not just silent bystanders, but rather actively boost carcinogenesis by promoting excessive tumor initiation, malignant progression, metastasis, and therapeutic resistance. The transformed cancer cells are found to interact with stromal cells in the TME, which contribute extensively to tumor development and resistance. Additionally, hyperplasia, metabolic remodeling, malignant proliferation, and inhibition of apoptosis in tumor cells contribute to hypoxia, oxidative stress, and acidosis within the TME. These abnormal conditions further modulate the ECM to induce angiogenesis or mechanical stiffness, and ultimately result in metastasis and resistance. CAFs induce cancer progression as well as therapeutic resistance through the secretion of cytokines or chemokines, exosomes, and ECM remodeling factors. Macrophages, adipocytes, and fibroblasts in the TME can also act as a sanctuary for tumor cells to escape immune elimination. Therefore, combination chemotherapy with drugs targeting the TME, such as immune cells and angiogenesis, has had success in clinical trials for overcoming drug resistance.

Accordingly, an interesting concept has been proposed that the resistance of tumor cells to multiple therapies may be caused by both active (cell-autonomous) and adaptive (non-cell-autonomous) mechanisms. While numerous active mechanisms of therapeutic resistance have been summarized previously, here, we focus on the adaptive resistance to various therapies mainly dependent on the TME (Figure 1). Furthermore, the complex reciprocity between tumors and TME and its role in adaptive resistance is discussed, with a perspective on prospects of overcoming therapeutic resistance.

TME-Driven Adaptive Mechanisms of Therapy Resistance

The TME contains a wide variety of cell types including CAFs, immune cells, and vascular cells embedded in the ECM. The TME also contains exosomes, metabolites and cytokines that mediate heterocellular interactions. Moreover, the physical or chemical features, including hypoxia, acidity, and oxidative stress, all facilitate tumor progression and resistance.

Cancer-Associated Fibroblasts (CAFs)

Cancer-associated fibroblasts are a prevalent subpopulation of cells in the tumor stroma. The conversion from quiescence to activation of fibroblasts provokes various oncogenic signals that facilitate tumor cells to escape therapies. Co-culture of prostate tumor cells with CAFs attenuates doxorubicin cytotoxicity by obstructing DNA damage and suppressing ROS generation in tumor cells. CAFs may also be responsible for the resistance of therapy through secreting chemokines, growth factors, metabolites, and exosomes, causing resistance and recurrence (Figure 2). CAF-secreted PAI-1 activates the AKT and MAPK pathways in a paracrine way to reduce chemotherapy drug-induced DNA damage, ROS generation, and cell death in esophageal squamous cell carcinoma (ESCC). HGF secreted by CAFs can combine with the MET receptor to activate the PI3K-Akt and MAPK pathways, which is responsible for the resistance of BRAF inhibitors or EGFR inhibitors to glioblastoma, colon cancer, and melanoma. In addition, CAF-derived paracrine signals including chemoattractant cytokines, metabolites, and exosomes induce the NF-κB pathway, contributing to tumor cell resistance. Treatment with chemotherapeutic drugs upregulates WNT16B in CAFs, which mitigates the cytotoxic effects of drugs through the NF-κB pathway in prostate cancer cells. Similarly, secreted IL-1β and the constitutively expressed IL-1 receptor associated kinase 4 (IRAK4) induce the activation of the NF-κB pathway both in CAFs and pancreatic cancer cells, alleviating the cytotoxicity of gemcitabine in pancreatic tumors. IL-6 is another cytokine released by CAFs that promotes cisplatin resistance through the STAT3/NF-κB pathway by upregulating CXCR7 in ESCC.

Given the pivotal role of CSCs in therapeutic resistance, the CAFs strengthen stemness as a route of acquired resistance. The IL-6 and IL-8 released by CD10+GPR77+ CAFs can promote CSCs sustaining chemotherapy resistance in breast and lung tumors. Meanwhile, chemotherapy-treated colorectal CAFs promote the self-renewal of CSCs by increasing the secretion of interleukin-17A (IL-17A). In addition, TGF-β2 secreted by CAFs cooperate with HIF-1α derived from the hypoxic TME to activate the Hedgehog pathway, which promotes cancer cell stemness and resistance to chemotherapy. Moreover, ELF chemokines secreted by CAFs are also proven to induce the transformation of tumor cells to stem cells in breast and pancreatic tumors. The secretion of FGF5 by Hedgehog-activated CAFs in mouse models of breast cancer creates a supportive microenvironment for cancer cells by fostering a reversible stem-like phenotype. Indeed, inhibition of Hedgehog signaling by Smo inhibitors can hinder the transformation toward stemness status to recover the sensitivity of cancer cells to docetaxel.

Furthermore, the complicated crosstalk between CAFs and tumor cells also contributes to resistance. For example, epithelial expression of platelet-derived growth factor (PDGF)-CC causes the CAFs to secrete STC1, IGFBP3, and HGF, which are responsible for the tamoxifen resistance in breast cancer. To escape tumor treatment, the upregulated insulin receptor (IR) and insulin-like growth factor (IGF) 1 receptor (IGF1R) in cholangiocarcinoma (CCA) cancer cells promote the proliferation and activation of CAFs. CAF-secreted IGF2 provides a feedback pathway with IR/IGF1R to induce the resistance of cancer cells to erlotinib, a tyrosine kinase inhibitor (TKI). Hence, an IR/IGF1R inhibitor can improve the deleterious effect of erlotinib in xenografts models. Additionally, cancer cell-derived serum components, such as lysophosphatidic acid (LPA) and proteases, are reported to stimulate CAFs remodeling for tumor cells survival. The remodeled CAFs, however, exert paracrine actions on tumor resistance via secreted growth factors, including VEGF-A, TGF-β, and various cytokines. CAFs-tumor cell contact can also activate the NOTCH signaling pathway, facilitating stroma-mediated radiotherapy.

In general, the above evidence has shed light on the adaptive mechanism that CAFs utilize with tumor cells for acquired resistance in many cancers including lung, breast, prostate, and glioblastoma. CAFs can interact with various TME factors including immune cells, tumor cells, and the ECM to participate in tumor cell resistance. The heterogeneous nature of CAFs and their multiple functions are interesting potential research directions as they offer a promising strategy for novel cutting-edge therapies directed at tumors and the TME.

Immune Cells

The immune cells in the TME mainly consist of B cells, effector and regulatory T cells, TAMs, myeloid-derived suppressor cells (MDSCs), natural killer cells (NKs) as well as dendritic cells (DCs). These cells are crucial for tumorigenesis, exerting either promoting or antagonizing effects on tumors. Cytotoxic CD8+ T cells (CTLs) are the primary lymphocytes for killing tumor cells. They secrete cytotoxic enzymes including perforin and granzyme, and can interact with the major histocompatibility complex I (MHC-I). The involvement of CTLs in tumor therapeutic resistance is proven by the strong association between the profile of CTLs in tumors and the chemotherapy outcomes (Figure 3). In ovarian cancer, CTLs can enhance the immunogenic action of IFN-β to abrogate CAF-mediated resistance to platinum-based chemotherapy. Indeed, the combination of cisplatin with immune checkpoint inhibitors (ICIs) have been shown to result in better clinical outcomes. TAMs are one of the most abundant cells detected in solid tumors and are derived from circulating monocytes. They also play an important role in controlling the immunosuppressive mechanisms of the TME, contributing to tumor development and therapeutic resistance. Evidence implicates TAMs in the secretion of cytokines including IL-6 and IFN in response to resistance. Blocking colony stimulating factor 1 receptor (CSF-1R) signaling to regulate the polarization status of TAMs has been found to be an effective way of restoring the sensitivity of cisplatin involving IFN response. Accordingly, these promising results have encouraged the evaluation of combination therapy strategies targeting the immune system for tumor patients.

Growing evidence suggests that immunotherapy has shown dramatic efficacy in clinical outcomes. However, some cancer patients treated using this approach show limited response rates due to acquired resistance. It has been shown that acquired immune resistance may be achieved by three approaches: (i) increased levels of immunosuppressive cells and molecules; (ii) upregulation of immune checkpoints; and (iii) tumor mutation loads and loss of target antigens. For example, enhanced recruitment of immunosuppressive cells, such as TAMs and MDSCs, reduces the sensitivity of immunotherapy and enhances immunosuppression, leading to acquired resistance. have demonstrated that apoptotic Tregs can upregulate the level of extracellular adenosine which can be correlated with acquired resistance to anti-PD-L1 mAb treatment in mice models. Moreover, the compensatory inhibitory mechanism also contributes to acquired resistance. For instance, increased CD4+TIM-3+ and CD8+TIM-3+ T cells in lung tumor biopsies has been related with resistance to anti-PD-1 mAb in both humans and mice. Similarly, increased TIM-3 on CTLs has been reported in HNSCC following treatment with anti-PD-1 mAb. The alteration of neoantigens may be another reason for acquired resistance, as manifested by the fact that loss of CD19 causes resistance following CD19-CAR-T cell therapy. Interestingly, the latest studies implicate that the serine protease inhibitor SerpinB9 (Sb9), expressed in CAFs, MDSCs, and TAMs, can promote tumor cell proliferation by combining with granzyme B (GrB) leading to resistance to immunotherapy.

Vasculature System

Numerous studies have shown that the responsiveness of tumors to therapy is affected by the vasculature system. Mechanically, the vasculature influences drugs transportation and sensitivity by controlling the supply of nutrients and oxygen, ultimately regulating tumor cell survival. The vasculature transports nutrients and oxygen, as well as other growth factors, to both normal and tumor tissue, and removes waste products following cellular metabolism, which can be involved in tumor relapse, metastasis, and resistance. Vessels in tumors are observed to be convoluted, branched, and dilated, with excessive loops compared with normal tissues. In some cases, vessels cannot be transformed into capillaries, arterioles, or venules. Moreover, vessel walls are often discontinuous or absent compared with normal tissues leading to varying degrees of leakiness in different tumors. Accordingly, blood flow in tumors becomes chaotic and variable. In the tumor vascular network, the viscosity and geometric resistance of blood is increased, and the pressure between arterioles and venules is depressed. Further, in normal tissues, pressure is reduced via the lymphatic network. However, lymph vessels are found to be lacking or have reduced functionality in solid tumors compared with normal tissues, leading to higher interstitial pressure. This higher interstitial pressure can suppress the transportation and distribution of larger biological molecules, and diverts blood away from the center toward the periphery of the tumor. Interestingly, even in the same tumor, the rate of blood flow or morphology of vessels may vary with space and time. These aberrant vasculature systems, and the dimensional compression of vessels caused by the excessive proliferation of tumor cells, reduce the rate of blood flow and impair the nutrition and oxygen supply to the tumor tissues. The insufficient supply of nutrients and oxygen as well as clearance of metabolic waste creates an acidic and hypoxic TME, which promotes therapeutic resistance.

Further, the synergistic effect of various cell types in the TME, such as pericytes, endothelial cells, and bone marrow-derived progenitors, is the basis of tumor angiogenesis, which is reported to be sensitive to oxygen levels. Mesenchymal stem cells (MSCs), TAMs, and CAFs all promote tumor angiogenesis by releasing various angiogenesis-related ligands. For instance, increased VEGFA is associated with poor prognosis in metastatic tumors such as lung, colon, and renal cell carcinomas.

The delivery of drugs is also compromised by these aberrant vasculature systems. The infiltration gradient in the spatial distance from vascular components to tumor lesions is related to the distribution of drugs from the tissues to cancer cells. Microvascular density (MVD) is an important index for the clinical outcomes of carcinomas of the lung, breast, and liver. Growing evidence indicates that VEGF receptor inhibitor resistance is mainly caused by proangiogenic factors, suggesting that combination with anti-angiogenic agents may improve clinical outcomes compared with VEGF receptor inhibitors alone. In addition, the chemokine CXC motif ligand receptor (CXCR7) is reported to promote angiogenesis by increasing ERK1/2 phosphorylation. Interestingly, the CXCL12-CXCR7 complex has been shown to mediate pro-angiogenesis, tumor growth, lung metastasis, and resistance. Accordingly, anti-angiogenesis may be an affective therapy by specifically targeting tumor blood vessels.

Extracellular Matrix (ECM)

The ECM consists of fibrous protein (such as laminin, elastin, and collagen), proteoglycans, water, and microelements, weaving a complex fiber-based network to provide structural support and regulate cellular activities, including proliferation, communication, and adhesion. In tumors, both the composition and physical or chemical properties of the ECM are different, depending on the tumor tissue, resident cells, tumor staging, and therapeutic strategies. The ECM contributes to tumor resistance by influencing drug delivery, facilitating the escape from immune surveillance, and manipulating the transmembrane signaling transduction process.

Drugs are usually transported to the tumor issues by the pressure of blood circulation through interstitial areas. In this process, drugs need to cross the physical and biochemical barriers of the TME. The desmoplastic stroma has been found to be a barrier responsible for drug resistance by impeding the delivery of anti-cancer drugs and affecting vascular systems in tumors. In interstitial spaces, the organization of the ECM has been found to increase fluid pressure due to the barriers of the tumor mass, significantly suppressing the efficacy of drug delivery. Moreover, excessive proliferation of cancer cells promotes fluid flux from the neoplasms toward the surroundings which impedes drug transportation. Indeed, drug delivery efficiency has been demonstrated to be inhibited in the 3D cultured spheroids compared with the 2D monolayer owing to the density of the ECM cells. Furthermore, tumor cells within the collagen I matrix display obvious resistance when cells are exposed to 5-fluorouracil/oxaliplatin.

Besides influencing drug delivery, the ECM also plays an essential role in controlling cytokine activity, of which TGF-β is the most important. TGF-β induces the recruitment of fibroblasts to the tumor site and transformation to CAFs by regulating ECM matrix degradation. In addition, TGF-β along with HIF-1 can induce lysyl oxidase (LOX) which orchestrates ECM stiffness by inducing cross-linked collagen. ECM stiffness, in turn, can activate the TGF-β signaling pathway to form a bridge in the basement membrane and contribute to tumor cell evasion. Indeed, genomic and transcriptomic analysis have demonstrated that the activated gene sets in response to TGF-β signaling are involved in regulating various pathophysiological processes including EMT, wound healing, angiogenesis, and dissemination. On the other hand, TGF-β can regulate immune response by orchestrating the crosstalk of multiple cell types in the TME, including CAFs, lymphocytes, and endothelial cells. TGF-β can inhibit the proliferation and differentiation of anti-tumor T cells by increasing the expression of CD25 and Foxp3. Moreover, TGF-β induces the secretion of monocyte chemoattractant protein-1 (MCP-1) to upregulate the expression of mesenchymal markers and chemotactic factors (CCL-2, 7, 8, 13), which are associated with anti-PD-1 immune resistance.

Among the multiple TME factors that impact cancer cell therapy resistance, cell adhesion to the ECM has been considered as a key determinant. In particular, cell adhesion-mediated drug resistance depends on interactions between integrins and ECM components such as collagen, fibronectin, and laminin. Integrin-mediated resistance has been reported to influence chemical drugs, radiotherapy, and targeted therapies such as TKIs. It has been reported that the treatment of fibronectin or collagen-deficient ECMs with cisplatin increases the sensitivity of tumor cells by about 40%. The loss of integrin subunits, such as αvβ3 or αvβ5, can significantly restore the sensitization of glioblastoma and breast tumor cells to radiotherapy. The silencing of the αv subunit also increases the efficacy of oxaliplatin in colon tumor cells. Additionally, the over-expression of β1 integrin significantly inhibits cell death in hepatocellular carcinoma exposed to etoposide, cisplatin, or docetaxel. Mechanically, integrins transmit the signals in the microenvironment into intracellular pathways through focal adhesion kinase (FAK) and integrin-linked kinase (ILK). The complexes of FAK, ILK, cortactin, and cysteine-histidine-rich 1 as well as parvin α have been reported to inhibit the outcome of radiotherapy. Integrin β1 regulates the dephosphorylation of FAK to protect tumor cells resistant to radiotherapy in a JNK-dependent manner on HNSCC and PDAC in vitro and in vivo. Blocking the α5β1 subunit reduces the resistance to ellipticine and temozolomide dependent on p53 mutation status in glioblastoma cells. Upregulated α4 integrin is responsible for the resistance in AML and esophageal cancer cells via the PI3K/Akt pathway. Additionally, a few findings suggest that the NF-κB or ILK-RhoB pathways may be involved in integrin-mediated resistance. The ECM proteoglycan, versican, can impact immune surveillance evasion along with hyaluronan by increasing the expression of inflammatory cytokines such as IL-6, TNFα, and NF-κB. Taken together, the complexity of the ECM in composition and structure as well as heterogeneity still needs to be further understood for therapeutic purposes.

TME-Derived Exosomes

Exosomes or extracellular vesicles (EVs) with sizes of 40 to 100 nm, originating from large multivesicular bodies (MVBs), mediate cell-to-cell communication by transferring biologically active cargo, including DNAs, RNAs, proteins, and metabolites. Exosomes have been demonstrated to be crucial signaling mediators in the TME, participating in tumorigenesis, metastasis, TME remodeling, angiogenesis, and therapeutic resistance (Figure 4). For example, exosomes have been found to control metabolic reprogramming. Exosomes can also scavenge unfavorable molecules in normal cells. Cancer cells hijack exosomes for the efflux of anti-cancer drugs, resulting in drug resistance. Thus, drug-resistant ovarian carcinoma cells exhibit an enhanced exosomal export of cisplatin together with putative transporters MRP2, ATP7A, and ATP7B.

Exosomes and their cargos can also promote the drug resistance of target cells. Exosomes extracted from resistant breast and prostate cancer cells have been shown to contain MDR1/P-gp transporters, conferring resistance to drug-sensitive tumor cells. miR-155 in exosomes has been reported to induce chemo-resistance by increasing the FOXO-3a, TGF-β, and C/EBP-β-mediated expression of EMT markers. Notably, exosomes isolated from triple-negative breast cancer cells can induce drug resistance on non-tumorigenic breast cells by modulating the PI3K/AKT, MAPK, and HIF1A pathways. Additionally, lymphoma exosomes carrying CD20 shield target cells form an antibody attack via the complement consumption of therapeutic anti-CD20 antibodies, leading to evasion of humoral immunotherapy.

Intriguingly, exosomes also promote therapeutic resistance by facilitating the intricate crosstalk between tumor cells and non-tumor cells within the TME. RNAs within exosomes derived from stromal cells activate the pattern recognition receptor RIG-I and downstream STAT1 signaling, which facilitates the growth of resistant tumor cells. Exosomes secreted by TAMs transfer miR-21 to gastric cancer cells, which activates the PI3K/AKT signaling pathway and suppresses cell apoptosis to confer resistance. Meanwhile, TAMs can directly deliver mRNAs to enhance the expression of CDK6, mTOR, STAT3, and β-catenin, leading to cisplatin resistance in BCa cells. In another example, exosomes released from CAFs strengthen the chemo-resistance of pancreatic cancer cells and colorectal cancer cells by activating β-catenin and the Snail pathway.

Collectively, exosomes can cause tumor cells to acquire resistance by various pathways, including the reduction of intracellular drug concentrations, induction of EMT, activation of anti-apoptotic pathways, alteration of critical survival signal transduction pathways, and modulation of the immune system.

Hypoxia, Acidity, and Oxidative Stress

The abnormal vasculature and heavy requirement for oxygen in tumors create a chronic or diffusion-limited hypoxia and acid environment. The hypoxic environment of tumors leads to a decreased supply of nutrients such as glucose and essential amino acids. Moreover, tumor cells prefer to undergo glycolysis rather than oxidative metabolism which often converts glucose to lactate for the production of ATP, resulting in sequential acidic microenvironments. Furthermore, a decreased capability of removing these acidic products results in low interstitial pH, another feature of solid tumors. These hypoxic and acidic conditions will induce aberrant activation of oncogenic pathways and genetic instability, contributing to tumor development and resistance. For example, hypoxia in tumors increases the expression of multiple genes associated with angiogenesis and cell survival by activating HIF-1, a basic helix-loop-helix transcription factor (bHLH). Serving as an oxygen sensor, HIF-1 may promote the expansion of tumor cell populations and alteration of biochemical metabolites involved in a resistant phenotype in response to hypoxia. It has been shown that hypoxia reduces sensitivity to p53-mediated apoptosis and promotes chemotherapeutic resistance in tumor cells. In solid tumors, the activation of major oncogenic signaling pathways such as Ras and PI3K/AKT, and the silencing of tumor suppressors LKB1, PTEN, and TSC2/1 can activate HIF-1, contributing to resistance. Stabilization of HIF-1α through interaction with Hsp90/Hsp70 also facilitates cell survival under stress conditions. Additionally, HIF-1α can cooperate with CAF-secreted TGF-β2 to induce GLI2 signaling cancer stem cells, leading to enhanced stemness and chemotherapy resistance.

Mechanically, HIF-1 activation induces the transcription of genes that facilitate pathophysiological alterations related to resistance, including the suppression of apoptosis and the induction of drug efflux and metabolism. Apoptosis may be a major factor in cell death induced by chemo- or radio- therapies. Interestingly, HIF-1α has been found to both inhibit proapoptotic proteins, including TRAIL, and activate anti-apoptotic proteins, such as survivin, c-myc, STAT3, and TCF4, to promote the survival of tumor cells under chemo- or radio- therapies. HIF-1α also influences sensitivity to therapy through regulation of genes related to metabolic pathways. HIF-1α can upregulate GLUT-1 to promote glycolysis, leading to increased intracellular ATP, pyruvate, and lactate levels, while the suppression of HIF-1α results in a reduced glucose uptake, decreased lactate production, and increased oxygen species (ROS), which contribute to the enhanced efficacy of radiotherapy. Hypoxia has been reported to promote temozolomide (TMZ) resistance in glioblastoma multiforme (GBM), through the activation of HIF-1α and NF-κB, followed by upregulated expression of Bcl-xL. Transient hypoxia has also been found to cause an increase in dihydrofolate reductase and P-glycoprotein, which contributes to the resistance of drugs targeting topoisomerase II. Interestingly, oxygen concentration may affect the efficacy of the anti-cancer drugs doxorubicin and mitomycin C, by delivering electrons to the oxygen.

Acidity in the TME has been demonstrated to affect the efficacy of various therapies. It can influence the transport of chemical drugs across the membrane due to the pH gradient caused by the acidic extracellular pH and near neutral or alkaline intracellular pH in tumors. Hence, drugs with an acidic dissociation constant of 7.5–9.5 may show a significantly reduced rate of uptake, such as vincristine, mitoxantrone, doxorubicin, and vinblastine. Therefore, the cytotoxicity of these drugs is suppressed, resulting in a resistant phenotype. However, the concentration of some weakly acidic drugs including cyclophosphamide and chlorambucil may be increased in the neutral intracellular region. Moreover, an acidic TME also alters the cellular proteome, cellular metabolism, and signaling pathways, facilitating stemness and drug resistance in cancer cells. The acidosis induces SOX2 expression by inhibiting vitamin D receptor (VDR)-mediated transcription, resulting in drug resistance. Enhanced lactate uptake and oxidation-induced lactic acidosis foster the resistance to uprosertib, a pan-Akt inhibitor, in colon cancer cells. Moreover, the acidic environment induces the activity of p-glycoprotein (pGP) by activating p38 signaling, leading to multi-drug resistance in rat prostate cancer cells (AT1). Clearly, the acidity of the TME must be considered when designing the delivery of drugs to obtain maximal therapeutic effect.

Oxidative stress is another feature of the TME, which is caused by the overproduction of reactive oxygen species (ROS) from both tumor cells and non-malignant cells in the TME. Oxidative stress plays a pivotal role in tumor progression, particularly through immune cell suppression. ROS downregulates the anti-tumor functions of effector immune cells that are recruited to the tumor site, notably T lymphocytes and natural killer (NK) cells which mediate anti-tumor immunity. MDSCs have been found to inhibit T cell proliferation to promote colorectal cancer cell proliferation by increasing ROS levels. ROS and peroxynitrite in MDSC trigger the nitration of the TCR/CD8 complex which inhibits its interaction with pMHC, contributing to T cell tolerance and tumor escape. ROS generated from NOX2-sufficient myeloid cells inhibits the NK cell-mediated clearance of malignant cells, facilitating the metastasis of melanoma cells. The NK cells residing in the tumor core or primed by IL-15 exhibit higher thiol densities that can prevent other lymphocytes from ROS within the TME. High levels of ROS following TCR and CD28 stimulation enhance Treg cell-mediated tumor immunosuppression and attenuate anti-tumor T cell responses by stabilizing SENP3. In conclusion, oxidative stress acts as an important mediator of anti-tumor immunity. Achieving targeted oxidative stress could be a potential strategy to improve the efficacies of existing immunotherapy treatment.

Heterocellular Metabolic Interactions

Growing evidence has demonstrated that disordered metabolism in the TME plays a crucial role in malignancy, metastasis, and immune resistance. The impact of metabolism on immune-resistance is mainly caused by two aspects: a reshaped immunosuppressive TME from tumor metabolic stress and immune-inhibiting metabolites generated by tumor cells.

Cancer cells usually exhibit high rates of glycolysis and aggressive depletion of amino acids such as tryptophan, arginine, and glutamine compared with normal cells. Tumor metabolic stress modulates the metabolic properties of malignant cells, which in turn influences nutrient shortage, oxygen competition, and acidity in the TME to create an immune-resistant environment. It is known that the demand for nutrients is especially high in TME, and this nutrient competition can impair the anti-cancer immune response. For example, the competition of carbohydrates can inhibit the anti-tumor effect of cytotoxic T cells by inducing the expression of immunosuppressive cytokines and immune checkpoint inhibitors. The restriction of glucose supplies due to the high rates of glycolysis in tumor cells impairs the anti-tumor function of CD4+ T cells, possibly by blocking the secretion of IFN-γ. Similarly, L-arginine deprivation has been found to inhibit anti-tumor immunity by inducing MDSC infiltration or suppressing the toxicity of IFN-γ. L-arginine depletion also promotes the immune evasion of cancer cells by elevating the tumoral level of PD-L1. Tryptophan is another crucial amino acid that contributes to the anti-tumor immune response by regulating the kynurenine metabolic pathway. Indoleamine 2,3-dioxygenase (IDO), an essential enzyme of the tryptophan metabolic pathway, controls the production of kynurenine which exerts immunosuppressive effects by inducing differentiation of T cells and reduces immunogenicity. Both inhibitory immune cells such as MDSCs, DCs, and M2 macrophages as well as tumor cells can express IDO. Cancer cells have also been found to reduce tryptophan levels in TME to inhibit immune response. Besides glucose and amino acid metabolic pathways, lipid-related metabolism also plays an essential regulatory role in immunosuppressive function. Obesity induces a desmoplastic TME by promoting inflammation and TAN infiltration, leading to impaired response to chemotherapy in PDAC. Reversal of obesity-aggravated desmoplasia by blocking the angiotensin-II type-1 receptor (AT1) improves response to chemotherapy. Meanwhile, cholesterol depletion can also recover the cytotoxic effect of chemical agents on PDAC and HCC. Fatty acids have also been demonstrated to determine the cell fate of T cells and CD8+ effector T cells.

In addition, a variety of tumor metabolites have been reported to promote immune evasion. Glutamine is the most abundant amino acid in the TME, playing an essential role in anabolic growth and metastasis. Recent research has demonstrated that glutamine metabolism can impair anti-cancer immune response. Glutamine blockade causes increased glucose and glutamine levels in the TME, inducing MDSCs apoptosis, promoting their differentiation toward the M1 type, and sensitizing resistant tumor cells to immunotherapies. Adenosine, the breakdown production of ATP, can active the adenosine-AR pathway to escape from the killing effects of the immune system by reducing the response of NK cells, M1 macrophages, and CD8+ effector T cells. In addition, methylglyoxal (MG), a side-production of glycolysis, is an immunosuppressive metabolite that promotes tumor cell growth and resistance. The high concentration of methylglyoxal in the TME derived from MDSCs leads to the accumulation of methylglyoxal in T cells, contributing to anti-tumor evasion. DMBG (N-N-dimethylbiguanide) can recover the sensitivity of immunotherapy-resistant tumor cells by removing the glycation activity of methylglyoxal. Another molecule that can establish an immunosuppressive TME is lactate, a product of glycolysis and glycogenolysis. Lactate induces the development of MDSCs, polarization of macrophages into an immunosuppressive phenotype, maturation of DCs, and inhibition of effector T cells, thereby promoting immune evasion. Furthermore, lactate can control CAFs to produce growth factors including hyaluronan.

Collectively, tumor cells reshape their metabolism adaptively which leads to the remodeling of the TME. The heterocellular metabolic interactions create an immunosuppressive TME, which subsequently enhances tumor proliferation and immune-therapy resistance. Thus, targeting tumor cell metabolism or metabolites in the TME should have great potential for recovering immunotherapy resistance.

The Epithelial Pathway in Response to TME

It is well known that tumor initiation and progression rely on bidirectional communications between tumor cells and the associated environment. Several signaling pathways in tumor cells, including Akt, mTOR, STAT3, and Notch, may be responsible for the altered tumor environment exposed to tumor therapies (Figure 5). Surprisingly, tumor cells can adaptively inhibit oncogenic AKT, which induces the secretion of inflammatory molecules such as IL-6/8 and extracellular vehicles (EVs) to restrict the damage induced by therapy. Thus, suppression of AKT signaling can increase drug resistance in tumor cells. Moreover, mTOR acts as a vital protein to regulate cell growth both in physiological and pathological conditions. It has been shown that the secretome in the TME can activate mTOR signaling after treatment. Blocking mTOR signaling can restore the sensitivity of several anti-tumor drugs including crizotinib, vemurafenib, and erlotinib. Additionally, the ATM-TRAF6-TAK1 axis related with DNA damage may be involved in these processes. Surprisingly, some metabolites in the TME, such as the lactate, have been reported to activate the mTOR pathway through glutamine metabolic pathways, inducing the resistance to VEGF inhibitors.

In addition, the STAT3 pathway can rapidly respond to cytokines, including L-1β and IL-6 released from neutrophils, TAMs, and CAFs in the TME. Activated STAT3 induces resistance by promoting EMT, increasing anti-apoptotic signaling, and regulating miRNAs and exosomes. For example, STAT3 can promote the secretion of exosomes by upregulating Rab, which induces platinum resistance in ovarian tumors. In addition, activated STAT3 can regulate the delivery of drugs by triggering vascular abnormalities. Notch is another crucial adaptive signaling pathway responsible for the TME-induced chemotherapy resistance of tumor cells. Exosomes derived from the stroma deliver Jag1, a Notch ligand, activate the Notch pathway to trigger resistance in breast tumor cells. CAFs also can release IL-6 to activate the Notch pathway in breast tumor cells. Induction of Notch3 is also relevant to CSCs transformation in liver cancer. Accordingly, these signaling pathways response to TME may be potential targets from a therapeutic perspective.

Targeting the Tumor Microenvironment for Therapy

Multiple preclinical studies implicate the TME as a potential therapeutic target. For instance, multiple strategies of combined therapy related to the TME have shown interesting potential (Table 1). In the TME, tumor cells usually hijack CAFs, ECM, the immune system, hypoxia, and acidosis-related pathways to escape immune surveillance. For example, dysregulated immune signaling pathways have been proven to impair several processes including antigen presentation and T cell infiltration. Thus, targeting the TME might have the potential ability to reverse the resistance of tumor cells.

Targeting Cancer-Associated Fibroblasts

Given the critical role of CAFs, the most abundant cell type in the TME, in therapeutic resistance of tumor cells, emerging evidence supports targeting protumorigenic CAF functions as a promising approach for tumor therapy. For example, conophylline is used to treat refractory pancreatic cancers by suppressing CAF activity and the proliferation and secretion of cytokines. The cell surface markers GPR77 and CD10, specifically expressed in CAFs, are involved in chemo-resistance in lung and breast cancer. Treatment with inhibitors of these molecules is a breakthrough in overcoming resistance. For example, using a GPR77-neutralizing antibody to selectively inhibit CAFs is an effective way to restore the sensitivity of drugs. Another strategy is to inhibit the activation of protumorigenic pathways in CAFs. Inhibition of Hedgehog signaling in CAFs successfully enhances the effect of docetaxel chemotherapy in TNBC patients. In addition, reversing activated CAFs into a dormant state is also an effective therapeutic strategy. The VDR is considered to be a targeted molecule that regulates the transcriptional process to activate CAFs in pancreatic cancer. Interestingly, compared with gemcitabine alone, the synergistic effect of gemcitabine and a VDR ligand suppresses fibrosis and inflammation, and restores the sensitivity of gemcitabine by increasing tumor uptake, thereby improving the survival rate to 57%. Studies have also found that nanoparticles loaded with a secreted sTRAIL can reduce the activation of CAFs in pancreatic cancers. Currently, some clinical trials targeting CAFs are being implemented. The agent RO6874281 is an interleukin-2 variant targeting FAP that is being evaluated for its clinical benefit in combination with atezolizumab, gemcitabine, or vinorelbine in the treatment of advanced tumors. The synergistic treatment of RO6874281 with trastuzumab or cetuximab in patients with head and neck cancer or breast tumors is also in clinical trials.

Targeting the Extracellular Matrix

Blocking the communication between tumor cells and their environment by targeting adhesion molecules, proteolytic enzymes, and ECM components has been demonstrated as an efficient strategy for tumor therapy. For example, suppression of the integrin-mediated bidirectional transmitting signals between cells and ECM has been used to prevent therapeutic resistance. Blocking the activity of β1 integrin with monoclonal antibody AIIB2 can significantly increase the outcome of HER2-targeting agents as well as radiotherapy. The antagonist of integrin α4β1 and α4β7, natalizumab, has been proven to recover the sensitivity of chemotherapy drugs in malignant tumors, including acute lymphoblastic leukemia (AML) and ovarian tumor. Matrix metalloproteinases (MMPs), one of the major ECM components, function as proteases to detach cancer cells out of the ECM, participating in tumor development, metastasis, and resistance. Several agents targeting MMPs have been developed for treating advanced carcinomas including incyclinide, JNJ0966 for MMP-9, and the antibody Fab 3369 for MMP-14.

TGF-β signaling is another pathway which mediates communication between tumor cells and their ECM. Therefore, anti-TGFβ drugs, including neutralizing antibodies, ligand traps, small-molecule kinase inhibitors, and antisense oligonucleotides (AONs), are a potential strategy for improving therapeutic efficacy. Blocking TGF-β by 1D11, a TGF-β neutralizing antibody, can improve the intra-tumoral penetration of both chemotherapeutic drugs and nanotherapeutic agents by normalizing the tumor interstitial matrix, thereby resulting in a better control of tumor growth. Galunisertib (LY2157299), an oral small-molecule inhibitor of TβRI, sensitizes colorectal cancer cells to RTK inhibitors. Blockade of TGF-β has been found to promote the anti-tumor activity of CD8+ T cells, thereby reversing the resistance to a PD-1/PD-L1 blockade in the TME. Moreover, TGF-β blockade by expressing dominant-negative TGF-β receptor II enhances the efficacy of TCR gene therapy against advanced cancers. Both fresolimumab, a pan-TGF-β neutralizing antibody, and LY3022859, an anti-TβRII IgG1 monoclonal antibody, exhibited anti-tumor activity in a phase 1 clinical trial for various cancers. TβR inhibitors, including LY2157299 and PF06952229, have being tested in clinical trials for patients with advanced or drug-resistant cancers (NCT03685591).

However, some studies suggest that targeting the ECM has limited outcomes in advanced malignancies such as GBM, melanoma, and prostate tumors, suggesting that different tumors with different extracellular matrices can exhibit different results. Therefore, further investigation and clinical trials are necessary to ensure treatment using ECM-targeting strategies are effective and safe.

Targeting the Immune System

As mentioned above, the immune system in TME dramatically affects the response of tumors to various treatment approaches. Therefore, multiple strategies based on targeting the immune system have been used to tackle cancers: (i) inhibiting the recruitment of macrophages to tumor tissues; (ii) blocking the differentiation of macrophages toward TAMs; (iii) enhancing the anti-tumor activity of the immune system. Several studies indicate that combination treatment using conventional therapies and immunotherapy achieves satisfactory clinical outcomes. Indeed, the combination of chemotherapy drugs and immune checkpoint inhibitors (ICIs) has shown a better result compared with chemotherapy alone. Consistently, targeting CTLs with pembrolizumab enhances the clinical efficacy of cisplatin in drug-resistant patients. These promising results have prompted a series of clinical studies to validate this combination therapy strategy. The suppression of MDSCs by anti-CSF-1R neutralizing antibodies or small molecule inhibitors has been shown to reduce tumor growth and metastasis. Immune checkpoint molecules in NKs were also reported to be potential targets for immunotherapy. To date approximately 174 clinical trials involving CTLA-4 and 750 involving PD-1 and its receptor PD-L1 have been reported (as reviewed in;; ). A combination with blocking antibodies against CTLA-4 and PD-1 results in significantly higher response rates and improved survival in patients with metastatic melanoma. Moreover, Kineret, an IL-1 receptor antagonist that is often used for rheumatoid arthritis, has exhibited promising results for breast cancer patients. The anti-IL-1 antibody canakinumab, which is often used for inflammatory diseases, has shown improved clinical outcomes in lung cancer. More recently, canakinumab has been proposed for the treatment of highly aggressive tumors NSCLC and triple negative breast cancer. In addition, combining traditional therapies with immune therapies has shown potential to reverse resistance. For example, the combination of HMTs with immune therapy has shown efficacy for various cancer in pre-clinical studies. Treatment with EZH2 inhibitor and antibodies blocking CTLA-4 was reported to reverse immunosuppressive effects and significantly improve survival in preclinical models. Moreover, DNMTi or HDACi treatment was reported to sensitize resistant cancer cells in mouse models of melanoma and lung adenocarcinoma. The combination of HDACis, DNMTis, anti-CTLA4, and anti-PD1 together showed significantly improved rates of survival, with 75% of mice with tumors being cured. Thus, targeting the immune system, especially in combination with traditional chemotherapy to promote survival and reverse resistance, may prove to be a safe and effective strategy for multiple types of tumors, benefitting more patients.

Targeting Hypoxia and Acidosis

As mentioned above, low oxygen pressure and acidosis conditions in the TME dramatically affect a tumor’s response to treatment. Therefore, it is rational to manipulate hypoxia and acidosis conditions in the TME to hinder tumor progression. Accordingly, topotecan, an inhibitor of HIF-1α, has been used to cure advanced tumors including ovarian and small cell lung cancers. Topotecan has also been used in a clinical study for the treatment of refractory advanced solid neoplasms expressing HIF-1α. Additionally, several clinical trials based on intervention against hypoxia are underway, including the evaluation of everolimus, which downregulates HIF-1α, in combination with lenvatinib in renal cancer (NCT01206764), as well as an evaluation of the metformin outcomes in tissue oxygenation of head and neck cancer (NCT03510390). The acidified environment has been considered to protect tumor cells from chemotherapy by affecting the concentration of drugs. Hence, recent clinical trials have focused on alteration of the acidification environment by targeting carbonic anhydrases, a family of enzymes that regulate the pH of active cells/tissues in tumors. For example, the synergistic treatment of acetazolamide, a carbonic anhydrase inhibitor, with radiotherapy has been tested in lung cancer (NCT03467360) while the combination of acetazolamide and temozolomide has also been trialed for brain cancer (NCT03011671).

Discussion

In this review, we have summarized the current insights into how the TME regulates cancer resistance to therapies. The adaptive resistance to cancer treatment driven by the TME may play a vital role in tumor recurrence and metastasis. Therefore, a variety of approaches targeting the TME have been developed to reverse resistance to radiotherapy, chemotherapy, and immunotherapy. Hijacking the TME to increase drug delivery has also been demonstrated to enhance the efficacy of chemotherapeutic drugs. Although a large number of studies have shown the successful application of manipulating the TME to overcome resistance, there are several key questions that still need to be resolved. Firstly, the mechanisms underlying adaptive and non-adaptive resistance need further investigation in a real TME. To date, most of the studies have been based on resistant cells in vitro, which excludes the factors in the TME that may be vital for acquired resistance in vivo. Co-culture of tumor cells with other types of cells within the TME and tumor-microenvironment-on-a-chip (TMOC) models can only partially mimic the real TME. More studies should be conducted using appropriate mouse models, or the use of human organoids isolated from patient biopsies, to fully understand the role of TME adaptive and non-adaptive resistance. Secondly, since the TME changes dynamically during the development and treatment of tumors, understanding and monitoring the factors that influence the therapeutic effects of targeting the TME is necessary to improve patient safety and survival outcome. Lastly, some drawbacks of targeting the TME, such as immune-related side-effects, may lead to the cessation of treatment. Hopefully, as our understating of intrinsic biology of the TME is improved, we will be more capable of preempting or reversing cancer therapy resistance.

Author Contributions

NX, JL, and PW conceptualized the manuscript. PW and WG collected the literature and wrote the manuscript. MS and WZ made the figures. EN made significant revisions to the manuscript. All authors read and approved the final manuscript.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

References 369

  1. 1.

    Acosta J. C. Banito A. Wuestefeld T. Georgilis A. Janich P. Morton J. P. (2013 ). A complex secretory program orchestrated by the inflammasome controls paracrine senescence. Nat. Cell Biol. 15 978–990.

    Not in our library10.1038/ncb2784

  2. 2.

    Ahmed K. M. Zhang H. Park C. C. (2013 ). NF-κB regulates radioresistance mediated By β1-Integrin in three-dimensional culture of breast cancer cells. Cancer Res. 73 3737–3748.

    Not in our library10.1158/0008-5472.can-12-3537

  3. 3.
  4. 4.

    Amini M. A. Abbasi A. Z. Cai P. Lip H. Gordijo C. R. Li J. (2019 ). Combining tumor microenvironment modulating nanoparticles with doxorubicin to enhance chemotherapeutic efficacy and boost antitumor immunity. J. Natl. Cancer Inst. 111 399–408.

    Not in our library10.1093/jnci/djy131

  5. 5.

    Angelin A. Gil-de-Gómez L. Dahiya S. Jiao J. Guo L. Levine M. H. (2017 ). Foxp3 reprograms T Cell metabolism to function in low-glucose, high-lactate environments. Cell Metab. 25 1282.e7–1293.e7.

    Not in our library10.1016/j.cmet.2016.12.018

  6. 6.

    Antognelli C. Moretti S. Frosini R. Puxeddu E. Sidoni A. Talesa V. N. (2019 ). Methylglyoxal acts as a tumor-promoting factor in anaplastic thyroid cancer. Cells 8:547.

    Not in our library10.3390/cells8060547

  7. 7.

    Antognelli C. Talesa V. N. (2018 ). Glyoxalases in urological malignancies. Int. J. Mol. Sci. 19:415.

    Not in our library10.3390/ijms19020415

  8. 8.

    Apicella M. Giannoni E. Fiore S. Ferrari K. J. Fernández-Pérez D. Isella C. (2018 ). Increased lactate secretion by cancer cells sustains non-cell-autonomous adaptive resistance to MET and EGFR targeted therapies. Cell Metab. 28 848.e6–865.e6.

    Not in our library10.1016/j.cmet.2018.08.006

  9. 9.

    Ariotti C. Wagner V. P. Salvadori G. Carrard V. C. Martins M. A. T. da Cunha Filho J. J. (2015 ). VEGFR1 and VEGFR2 in lip carcinogenesis and its association with microvessel density. Tumor Biol. 36 7285–7292.

    Not in our library10.1007/s13277-015-3454-7

  10. 10.
    Tumor Microenvironment · 2019
    No notice
  11. 11.

    Assaraf Y. G. Brozovic A. Gonçalves A. C. Jurkovicova D. Linē A. Machuqueiro M. (2019 ). The multi-factorial nature of clinical multidrug resistance in cancer. Drug Resistance Updates 46:100645.

    Not in our library10.1016/j.drup.2019.100645

  12. 12.

    Aung T. Chapuy B. Vogel D. Wenzel D. Oppermann M. Lahmann M. (2011 ). Exosomal evasion of humoral immunotherapy in aggressive B-cell lymphoma modulated by ATP-binding cassette transporter A3. Proc. Natl. Acad. Sci. U.S.A. 108 15336–15341.

    Not in our library10.1073/pnas.1102855108

  13. 13.

    Aydin E. Johansson J. Nazir F. H. Hellstrand K. Martner A. (2017 ). Role of NOX2-derived reactive oxygen species in NK cell-mediated control of murine melanoma metastasis. Cancer Immunol. Res. 5 804–811.

    Not in our library10.1158/2326-6066.cir-16-0382

  14. 14.

    Balkwill F. R. Capasso M. Hagemann T. (2012 ). The tumor microenvironment at a glance. J. Cell Sci. 125(Pt 23), 5591–5596.

    Not in our library10.1242/jcs.116392

  15. 15.

    Barnes E. M. E. Xu Y. Benito A. Herendi L. Siskos A. P. Aboagye E. O. (2020 ). Lactic acidosis induces resistance to the pan-Akt inhibitor uprosertib in colon cancer cells. Br. J. Cancer 122 1298–1308.

    Not in our library10.1038/s41416-020-0777-y

  16. 16.

    Baumann T. Dunkel A. Schmid C. Schmitt S. Hiltensperger M. Lohr K. (2020 ). Regulatory myeloid cells paralyze T cells through cell-cell transfer of the metabolite methylglyoxal. Nat. Immunol. 21 555–566.

    Not in our library10.1038/s41590-020-0666-9

  17. 17.

    Belli C. Trapani D. Viale G. D’Amico P. Duso B. A. Della Vigna P. (2018 ). Targeting the microenvironment in solid tumors. Cancer Treat. Rev. 65 22–32.

    Not in our library10.1016/j.ctrv.2018.02.004

  18. 18.

    Bendle G. M. Linnemann C. Bies L. Song J. Y. Schumacher T. N. (2013 ). Blockade of TGF-β signaling greatly enhances the efficacy of TCR gene therapy of cancer. J. Immunol. 191 3232–3239.

    Not in our library10.4049/jimmunol.1301270

  19. 19.

    Benjamin L. E. Golijanin D. Itin A. Pode D. Keshet E. (1999 ). Selective ablation of immature blood vessels in established human tumors follows vascular endothelial growth factor withdrawal. J. Clin. Invest. 103 159–165.

    Not in our library10.1172/jci5028

  20. 20.
  21. 21.

    Billottet C. Tuefferd M. Gentien D. Rapinat A. Thiery J. P. Broët P. (2008 ). Modulation of several waves of gene expression during FGF-1 induced epithelial-mesenchymal transition of carcinoma cells. J. Cell Biochem. 104 826–839.

    Not in our library10.1002/jcb.21667

  22. 22.

    Boelens M. C. Wu T. J. Nabet B. Y. Xu B. Qiu Y. Yoon T. (2014 ). Exosome transfer from stromal to breast cancer cells regulates therapy resistance pathways. Cell 159 499–513.

    Not in our library10.1016/j.cell.2014.09.051

  23. 23.

    Boohaker R. J. Sambandam V. Segura I. Miller J. Suto M. Xu B. (2018 ). Rational design and development of a peptide inhibitor for the PD-1/PD-L1 interaction. Cancer Lett. 434 11–21.

    Not in our library10.1016/j.canlet.2018.04.031

  24. 24.

    Brand A. Singer K. Koehl G. E. Kolitzus M. Schoenhammer G. Thiel A. (2016 ). LDHA-associated lactic acid production blunts tumor immunosurveillance by T and NK cells. Cell Metab. 24 657–671.

    Not in our library10.1016/j.cmet.2016.08.011

  25. 25.

    Brown J. M. Wilson W. R. (2004 ). Exploiting tumour hypoxia in cancer treatment. Nat. Rev. Cancer 4 437–447.

    Not in our library10.1038/nrc1367

  26. 26.

    Brunen D. Willems S. Kellner U. Midgley R. Simon I. Bernards R. (2013 ). TGF-β: an emerging player in drug resistance. Cell Cycle 12 2960–2968.

    Not in our library10.4161/cc.26034

  27. 27.

    Bussink J. Kaanders J. H. van der Kogel A. J. (2003 ). Tumor hypoxia at the micro-regional level: clinical relevance and predictive value of exogenous and endogenous hypoxic cell markers. Radiother. Oncol. 67 3–15.

    Not in our library10.1016/s0167-8140(03)00011-2

  28. 28.

    Calvo F. Ege N. Grande-Garcia A. Hooper S. Jenkins R. P. Chaudhry S. I. (2013 ). Mechanotransduction and YAP-dependent matrix remodelling is required for the generation and maintenance of cancer-associated fibroblasts. Nat. Cell Biol. 15 637–646.

    Not in our library10.1038/ncb2756

  29. 29.

    Cao Q. Cai W. Li T. Yang Y. Chen K. Xing L. (2006 ). Combination of integrin siRNA and irradiation for breast cancer therapy. Biochem. Biophys. Res. Commun. 351 726–732.

    Not in our library10.1016/j.bbrc.2006.10.100

  30. 30.
  31. 31.

    Carmeliet P. Jain R. K. (2000 ). Angiogenesis in cancer and other diseases. Nature 407 249–257.

    Not in our library10.1038/35025220

  32. 32.
  33. 33.
  34. 34.
  35. 35.
  36. 36.

    Chan T. S. Hsu C. C. Pai V. C. Liao W. Y. Huang S. S. Tan K. T. (2016 ). Metronomic chemotherapy prevents therapy-induced stromal activation and induction of tumor-initiating cells. J. Exp. Med. 213 2967–2988.

    Not in our library10.1084/jem.20151665

  37. 37.

    Chang C. H. Qiu J. O’Sullivan D. Buck M. D. Noguchi T. Curtis J. D. (2015 ). Metabolic competition in the tumor microenvironment is a driver of cancer progression. Cell 162 1229–1241.

    Not in our library10.1016/j.cell.2015.08.016

  38. 38.

    Che Y. Wang J. Li Y. Lu Z. Huang J. Sun S. (2018 ). Cisplatin-activated PAI-1 secretion in the cancer-associated fibroblasts with paracrine effects promoting esophageal squamous cell carcinoma progression and causing chemoresistance. Cell Death Dis. 9 1–13.

    Not in our library10.1038/s41419-018-0808-2

  39. 39.
  40. 40.

    Chen W. L. Wang C. C. Lin Y. J. Wu C. P. Hsieh C. H. (2015 ). Cycling hypoxia induces chemoresistance through the activation of reactive oxygen species-mediated B-cell lymphoma extra-long pathway in glioblastoma multiforme. J. Transl. Med. 13:389.

    Not in our library10.1186/s12967-015-0758-8

  41. 41.

    Chen S. Sang N. (2016 ). Hypoxia-inducible factor-1: a critical player in the survival strategy of stressed cells. J. Cell Biochem. 117 267–278.

    Not in our library10.1002/jcb.25283

  42. 42.
  43. 43.

    Chen T. Li Q. Liu Z. Chen Y. Feng F. Sun H. (2019 ). Peptide-based and small synthetic molecule inhibitors on PD-1/PD-L1 pathway: a new choice for immunotherapy? Eur. J. Med. Chem. 161 378–398.

    Not in our library10.1016/j.ejmech.2018.10.044

  44. 44.

    Chen Y. Liu X. Yuan H. Yang Z. von Roemeling C. A. Qie Y. (2019 ). Therapeutic remodeling of the tumor microenvironment enhances nanoparticle delivery. Adv. Sci. 6:1802070.

    Not in our library10.1002/advs.201802070

  45. 45.

    Chen X. Wang L. Li P. Song M. Qin G. Gao Q. (2018 ). Dual TGF-β and PD-1 blockade synergistically enhances MAGE-A3-specific CD8(+) T cell response in esophageal squamous cell carcinoma. Int. J. Cancer 143 2561–2574.

    Not in our library10.1002/ijc.31730

  46. 46.

    Cheng P. Levesque M. P. Dummer R. Mangana J. (2020 ). Targeting complex, adaptive responses in melanoma therapy. Cancer Treatm. Rev. 86:101997.

    Not in our library10.1016/j.ctrv.2020.101997

  47. 47.

    Cheteh E. H. Augsten M. Rundqvist H. Bianchi J. Sarne V. Egevad L. (2017 ). Human cancer-associated fibroblasts enhance glutathione levels and antagonize drug-induced prostate cancer cell death. Cell Death Dis. 8:e2848.

    Not in our library10.1038/cddis.2017.225

  48. 48.

    Chiappinelli K. B. Zahnow C. A. Ahuja N. Baylin S. B. (2016 ). Combining epigenetic and immunotherapy to combat cancer. Cancer Res. 76 1683–1689.

    Not in our library10.1158/0008-5472.can-15-2125

  49. 49.

    Colak S. ten Dijke P. (2017 ). Targeting TGF-β signaling in cancer. Trends Cancer 3 56–71.

    Not in our library10.1016/j.trecan.2016.11.008

  50. 50.
  51. 51.
  52. 52.

    Correia A. L. Bissell M. J. (2012 ). The tumor microenvironment is a dominant force in multidrug resistance. Drug Resist. Updat 15 39–49.

    Not in our library10.1016/j.drup.2012.01.006

  53. 53.

    Cowan D. S. Tannock I. F. (2001 ). Factors that influence the penetration of methotrexate through solid tissue. Int. J. Cancer 91 120–125.

    Not in our library10.1002/1097-0215(20010101)91:1<120::aid-ijc1021>3.0.co;2-y

  54. 54.

    Crow J. Atay S. Banskota S. Artale B. Schmitt S. Godwin A. K. (2017 ). Exosomes as mediators of platinum resistance in ovarian cancer. Oncotarget 8:11917.

    Not in our library10.18632/oncotarget.14440

  55. 55.

    Cruz da Silva E. Dontenwill M. Choulier L. Lehmann M. (2019 ). Role of integrins in resistance to therapies targeting growth factor receptors in cancer. Cancers 11:692.

    Not in our library10.3390/cancers11050692

  56. 56.
  57. 57.

    Dang C. V. Semenza G. L. (1999 ). Oncogenic alterations of metabolism. Trends Biochem. Sci. 24 68–72.

    Not in our library10.1016/s0968-0004(98)01344-9

  58. 58.
  59. 59.

    Dauer P. Zhao X. Gupta V. K. Sharma N. Kesh K. Gnamlin P. (2018 ). Inactivation of cancer-associated-fibroblasts disrupts oncogenic signaling in pancreatic cancer cells and promotes its regression. Cancer Res. 78 1321–1333.

    Not in our library10.1158/0008-5472.can-17-2320

  60. 60.

    Denkert C. Loibl S. Noske A. Roller M. Muller B. Komor M. (2010 ). Tumor-associated lymphocytes as an independent predictor of response to neoadjuvant chemotherapy in breast cancer. J. Clin. Oncol. 28 105–113.

    Not in our library10.1200/jco.2009.23.7370

  61. 61.
  62. 62.

    Dhorepatil A. Ball S. Ghosh R. K. Kondapaneni M. Lavie C. J. (2019 ). Canakinumab: promises and future in cardiometabolic diseases and malignancy. Am. J. Med. 132 312–324.

    Not in our library10.1016/j.amjmed.2018.10.013

  63. 63.

    Díaz-Valdés N. Basagoiti M. Dotor J. Aranda F. Monreal I. Riezu-Boj J. I. (2011 ). Induction of monocyte chemoattractant protein-1 and interleukin-10 by TGFbeta1 in melanoma enhances tumor infiltration and immunosuppression. Cancer Res. 71 812–821.

    Not in our library10.1158/0008-5472.can-10-2698

  64. 64.

    Dorayappan K. D. P. Wanner R. Wallbillich J. J. Saini U. Zingarelli R. Suarez A. A. (2018 ). Hypoxia-induced exosomes contribute to a more aggressive and chemoresistant ovarian cancer phenotype: a novel mechanism linking STAT3/Rab proteins. Oncogene 37 3806–3821.

    Not in our library10.1038/s41388-018-0189-0

  65. 65.
  66. 66.

    Durand R. E. (2001 ). Intermittent blood flow in solid tumours–an under-appreciated source of ‘drug resistance’. Cancer Metastasis Rev. 20 57–61.

    Not in our library10.1023/a:1013181107707

  67. 67.

    Eisele G. Wick A. Eisele A.-C. Clément P. M. Tonn J. Tabatabai G. (2014 ). Cilengitide treatment of newly diagnosed glioblastoma patients does not alter patterns of progression. J. Neuro Oncol. 117 141–145.

    Not in our library10.1007/s11060-014-1365-x

  68. 68.

    Eke I. Cordes N. (2015 ). Focal adhesion signaling and therapy resistance in cancer. Semin. Cancer Biol. 31 65–75.

    Not in our library10.1016/j.semcancer.2014.07.009

  69. 69.

    Fang J. Zhang S. Xue X. Zhu X. Song S. Wang B. (2018 ). Quercetin and doxorubicin co-delivery using mesoporous silica nanoparticles enhance the efficacy of gastric carcinoma chemotherapy. Int. J. Nanomed. 13 5113–5126.

    Not in our library10.2147/ijn.s170862

  70. 70.

    Feichtinger R. G. Lang R. (2019 ). Targeting L-Lactate metabolism to overcome resistance to immune therapy of melanoma and other tumor entities. J. Oncol. 2019:2084195.

    Not in our library10.1155/2019/2084195

  71. 71.

    Ferlay J. Colombet M. Soerjomataram I. Mathers C. Parkin D. M. Piñeros M. (2019 ). Estimating the global cancer incidence and mortality in 2018: GLOBOCAN sources and methods. Int. J. Cancer 144 1941–1953.

    Not in our library10.1002/ijc.31937

  72. 72.
  73. 73.

    Fiori M. E. Villanova L. De Maria R. (2017 ). Cancer stem cells: at the forefront of personalized medicine and immunotherapy. Curr. Opin. Pharmacol. 35 1–11.

    Not in our library10.1016/j.coph.2017.04.006

  74. 74.

    Flaherty K. T. Manola J. B. Pins M. McDermott D. F. Atkins M. B. Dutcher J. J. (2015 ). BEST: a randomized phase II study of vascular endothelial growth factor, RAF kinase, and mammalian target of rapamycin combination targeted therapy with bevacizumab, sorafenib, and temsirolimus in advanced renal cell carcinoma—A trial of the ECOG–ACRIN Cancer Research Group (E2804). J. Clin. Oncol. 33:2384.

    Not in our library10.1200/jco.2015.60.9727

  75. 75.

    Fletcher M. Ramirez M. E. Sierra R. A. Raber P. Thevenot P. Al-Khami A. A. (2015 ). l-Arginine depletion blunts antitumor T-cell responses by inducing myeloid-derived suppressor cells. Cancer Res. 75 275–283.

    Not in our library10.1158/0008-5472.can-14-1491

  76. 76.

    Freund A. Orjalo A. V. Desprez P. Y. Campisi J. (2010 ). Inflammatory networks during cellular senescence: causes and consequences. Trends Mol. Med. 16 238–246.

    Not in our library10.1016/j.molmed.2010.03.003

  77. 77.

    Fu H. Yang H. Zhang X. Xu W. (2016 ). The emerging roles of exosomes in tumor-stroma interaction. J. Cancer Res. Clin. Oncol. 142 1897–1907.

    Not in our library10.1007/s00432-016-2145-0

  78. 78.

    Fujita M. Sasada M. Iyoda T. Fukai F. (2020 ). Involvement of integrin-activating peptides derived from tenascin-c in cancer aggression and new anticancer strategy using the fibronectin-derived integrin-inactivating peptide. Molecules 25:3239.

    Not in our library10.3390/molecules25143239

  79. 79.

    Gabrilovich D. I. Ostrand-Rosenberg S. Bronte V. (2012 ). Coordinated regulation of myeloid cells by tumours. Nat. Rev. Immunol. 12 253–268.

    Not in our library10.1038/nri3175

  80. 80.

    Galmarini F. C. Galmarini C. M. Sarchi M. I. Abulafia J. Galmarini D. (2000 ). Heterogeneous distribution of tumor blood supply affects the response to chemotherapy in patients with head and neck cancer. Microcirculation 7 405–410.

    Not in our library

  81. 81.

    Gamradt P. De La Fouchardière C. Hennino A. (2021 ). Stromal protein-mediated immune regulation in digestive cancers. Cancers 13:146.

    Not in our library10.3390/cancers13010146

  82. 82.

    Gandhi L. Rodríguez-Abreu D. Gadgeel S. Esteban E. Felip E. De Angelis F. (2018 ). Pembrolizumab plus chemotherapy in metastatic non–small-cell lung cancer. N. Engl. J. Med. 378 2078–2092.

    Not in our library10.1056/nejmoa1801005

  83. 83.
  84. 84.

    García-Cañaveras J. C. Chen L. Rabinowitz J. D. (2019 ). The tumor metabolic microenvironment: lessons from lactate. Cancer Res. 79 3155–3162.

    Not in our library10.1158/0008-5472.can-18-3726

  85. 85.

    Gargiulo E. Paggetti J. Moussay E. (2019 ). Hematological malignancy-derived small extracellular vesicles and tumor microenvironment: the art of turning foes into friends. Cells 8:511.

    Not in our library10.3390/cells8050511

  86. 86.

    Gerweck L. E. Vijayappa S. Kozin S. (2006 ). Tumor pH controls the in vivo efficacy of weak acid and base chemotherapeutics. Mol. Cancer Ther. 5 1275–1279.

    Not in our library10.1158/1535-7163.mct-06-0024

  87. 87.

    Gillies R. J. Schomack P. A. Secomb T. W. Raghunand N. (1999 ). Causes and effects of heterogeneous perfusion in tumors. Neoplasia 1 197–207.

    Not in our library10.1038/sj.neo.7900037

  88. 88.

    Goel H. L. Sayeed A. Breen M. Zarif M. J. Garlick D. S. Leav I. (2013 ). β1 integrins mediate resistance to ionizing radiation in vivo by inhibiting c-Jun amino terminal kinase 1. J. Cell. Physiol. 228 1601–1609.

    Not in our library10.1002/jcp.24323

  89. 89.

    Gomez S. Tabernacki T. Kobyra J. Roberts P. Chiappinelli K. B. (2020 ). Combining epigenetic and immune therapy to overcome cancer resistance. Semin. Cancer Biol. 65 99–113.

    Not in our library10.1016/j.semcancer.2019.12.019

  90. 90.

    Gordon-Weeks A. Yuzhalin A. E. (2020 ). Cancer extracellular matrix proteins regulate tumour immunity. Cancers 12:3331.

    Not in our library10.3390/cancers12113331

  91. 91.

    Gray M. D. Mann M. Nitiss J. L. Hendershot L. M. (2005 ). Activation of the unfolded protein response is necessary and sufficient for reducing topoisomerase IIalpha protein levels and decreasing sensitivity to topoisomerase-targeted drugs. Mol. Pharmacol. 68 1699–1707.

    Not in our library10.1124/mol.105.014753

  92. 92.

    Grivennikov S. I. Greten F. R. Karin M. (2010 ). Immunity, inflammation, and cancer. Cell 140 883–899.

    Not in our library10.1016/j.cell.2010.01.025

  93. 93.

    Guillaumond F. Bidaut G. Ouaissi M. Servais S. Gouirand V. Olivares O. (2015 ). Cholesterol uptake disruption, in association with chemotherapy, is a promising combined metabolic therapy for pancreatic adenocarcinoma. Proc. Natl. Acad. Sci. U.S.A. 112 2473–2478.

    Not in our library10.1073/pnas.1421601112

  94. 94.

    Guri Y. Hall M. N. (2016 ). mTOR signaling confers resistance to targeted cancer drugs. Trends Cancer 2 688–697.

    Not in our library10.1016/j.trecan.2016.10.006

  95. 95.

    Halama N. Michel S. Kloor M. Zoernig I. Benner A. Spille A. (2011 ). Localization and density of immune cells in the invasive margin of human colorectal cancer liver metastases are prognostic for response to chemotherapy. Cancer Res. 71 5670–5677.

    Not in our library10.1158/0008-5472.can-11-0268

  96. 96.

    Hanahan D. (2014 ). Rethinking the war on cancer. Lancet 383 558–563.

    Not in our library10.1016/s0140-6736(13)62226-6

  97. 97.

    Hanahan D. Coussens L. M. (2012 ). Accessories to the crime: functions of cells recruited to the tumor microenvironment. Cancer Cell 21 309–322.

    Not in our library10.1016/j.ccr.2012.02.022

  98. 98.

    Hanahan D. Weinberg R. A. (2011 ). Hallmarks of cancer: the next generation. Cell 144 646–674.

    Not in our library10.1016/j.cell.2011.02.013

  99. 99.

    Hashizume H. Baluk P. Morikawa S. McLean J. W. Thurston G. Roberge S. (2000 ). Openings between defective endothelial cells explain tumor vessel leakiness. Am. J. Pathol. 156 1363–1380.

    Not in our library10.1016/s0002-9440(10)65006-7

  100. 100.

    He J.-M. Wang F.-C. Qi H.-B. Li Y. Liang H.-J. (2009 ). Down-regulation of αv integrin by retroviral delivery of small interfering RNA reduces multicellular resistance of HT29. Cancer Lett. 284 182–188.

    Not in our library10.1016/j.canlet.2009.04.023

  101. 101.

    Hegde P. S. Jubb A. M. Chen D. Li N. F. Meng Y. G. Bernaards C. (2013 ). Predictive impact of circulating vascular endothelial growth factor in four phase III trials evaluating bevacizumab. Clin. Cancer Res. 19 929–937.

    Not in our library10.1158/1078-0432.ccr-12-2535

  102. 102.

    Heldin C.-H. Rubin K. Pietras K. Östman A. (2004 ). High interstitial fluid pressure—an obstacle in cancer therapy. Nat. Rev. Cancer 4 806–813.

    Not in our library10.1038/nrc1456

  103. 103.

    Hirata E. Sahai E. (2017 ). Tumor microenvironment and differential responses to therapy. Cold Spring Harbor Perspect. Med. 7:a026781.

    Not in our library10.1101/cshperspect.a026781

  104. 104.

    Ho P. C. Bihuniak J. D. Macintyre A. N. Staron M. Liu X. Amezquita R. (2015 ). phosphoenolpyruvate is a metabolic checkpoint of anti-tumor T Cell responses. Cell 162 1217–1228.

    Not in our library10.1016/j.cell.2015.08.012

  105. 105.

    Holle A. W. Young J. L. Spatz J. P. (2016 ). In vitro cancer cell–ECM interactions inform in vivo cancer treatment. Adv. Drug Deliv. Rev. 97 270–279.

    Not in our library10.1016/j.addr.2015.10.007

  106. 106.

    Holohan C. Van Schaeybroeck S. Longley D. B. Johnston P. G. (2013 ). Cancer drug resistance: an evolving paradigm. Nat. Rev. Cancer 13 714–726.

    Not in our library10.1038/nrc3599

  107. 107.

    Horvat T. Z. Adel N. G. Dang T.-O. Momtaz P. Postow M. A. Callahan M. K. (2015 ). Immune-related adverse events, need for systemic immunosuppression, and effects on survival and time to treatment failure in patients with melanoma treated with ipilimumab at memorial sloan kettering cancer center. J. Clin. Oncol. 33 3193–3198.

    Not in our library10.1200/jco.2015.60.8448

  108. 108.

    Houriet C. Jafari S. M. S. Thomi R. Schlapbach C. Borradori L. Yawalkar N. (2017 ). Canakinumab for severe hidradenitis suppurativa: preliminary experience in 2 cases. JAMA Dermatol. 153 1195–1197.

    Not in our library10.1001/jamadermatol.2017.2392

  109. 109.
  110. 110.

    Hsieh Y.-T. Gang E. J. Geng H. Park E. Huantes S. Chudziak D. (2013 ). Integrin alpha4 blockade sensitizes drug resistant pre-B acute lymphoblastic leukemia to chemotherapy. Blood 121 1814–1818.

    Not in our library10.1182/blood-2012-01-406272

  111. 111.

    Hu K. Miao L. Goodwin T. J. Li J. Liu Q. Huang L. (2017 ). Quercetin remodels the tumor microenvironment to improve the permeation, retention, and antitumor effects of nanoparticles. ACS Nano 11 4916–4925.

    Not in our library10.1021/acsnano.7b01522

  112. 112.

    Hu P.-S. Li T. Lin J.-F. Qiu M.-Z. Wang D.-S. Liu Z.-X. (2020 ). VDR–SOX2 signaling promotes colorectal cancer stemness and malignancy in an acidic microenvironment. Signal Transduct. Target. Ther. 5:183.

    Not in our library10.1038/s41392-020-00230-7

  113. 113.

    Huang C. Y. Kuo W. T. Huang Y. C. Lee T. C. Yu L. C. (2013 ). Resistance to hypoxia-induced necroptosis is conferred by glycolytic pyruvate scavenging of mitochondrial superoxide in colorectal cancer cells. Cell Death Dis. 4:e622.

    Not in our library10.1038/cddis.2013.149

  114. 114.

    Hugo W. Zaretsky J. M. Sun L. Song C. Moreno B. H. Hu-Lieskovan S. (2016 ). Genomic and transcriptomic features of response to Anti-PD-1 therapy in metastatic melanoma. Cell 165 35–44.

    Not in our library10.1016/j.cell.2016.02.065

  115. 115.

    Hui L. Chen Y. (2015 ). Tumor microenvironment: sanctuary of the devil. Cancer Lett. 368 7–13.

    Not in our library10.1016/j.canlet.2015.07.039

  116. 116.

    Husain Z. Huang Y. Seth P. Sukhatme V. P. (2013 ). Tumor-derived lactate modifies antitumor immune response: effect on myeloid-derived suppressor cells and NK cells. J. Immunol. 191 1486–1495.

    Not in our library10.4049/jimmunol.1202702

  117. 117.

    Incio J. Liu H. Suboj P. Chin S. M. Chen I. X. Pinter M. (2016 ). Obesity-induced inflammation and desmoplasia promote pancreatic cancer progression and resistance to chemotherapy. Cancer Discov. 6 852–869.

    Not in our library10.1158/2159-8290.cd-15-1177

  118. 118.

    Ishii N. Araki K. Yokobori T. Hagiwara K. Gantumur D. Yamanaka T. (2019 ). Conophylline suppresses pancreatic cancer desmoplasia and cancer-promoting cytokines produced by cancer-associated fibroblasts. Cancer Sci. 110 334–344.

    Not in our library10.1111/cas.13847

  119. 119.

    Itoh G. Chida S. Yanagihara K. Yashiro M. Aiba N. Tanaka M. (2017 ). Cancer-associated fibroblasts induce cancer cell apoptosis that regulates invasion mode of tumours. Oncogene 36 4434–4444.

    Not in our library10.1038/onc.2017.49

  120. 120.

    Jackaman C. Majewski D. Fox S. A. Nowak A. K. Nelson D. J. (2012 ). Chemotherapy broadens the range of tumor antigens seen by cytotoxic CD8(+) T cells in vivo. Cancer Immunol. Immunother. 61 2343–2356.

    Not in our library10.1007/s00262-012-1307-4

  121. 121.

    Jain R. K. (1988 ). Determinants of tumor blood flow: a review. Cancer Res. 48 2641–2658.

    Not in our library

  122. 122.

    Jeppesen D. K. Nawrocki A. Jensen S. G. Thorsen K. Whitehead B. Howard K. A. (2014 ). Quantitative proteomics of fractionated membrane and lumen exosome proteins from isogenic metastatic and nonmetastatic bladder cancer cells reveal differential expression of EMT factors. Proteomics 14 699–712.

    Not in our library10.1002/pmic.201300452

  123. 123.

    Jiang L. Wang Y.-J. Zhao J. Uehara M. Hou Q. Kasinath V. (2020 ). Direct tumor killing and immunotherapy through Anti-SerpinB9 therapy. Cell 183 1219.e18–1233.e18.

    Not in our library10.1016/j.cell.2020.10.045

  124. 124.

    Jiang W. Xia J. Xie S. Zou R. Pan S. Wang Z.-W. (2020 ). Long non-coding RNAs as a determinant of cancer drug resistance: towards the overcoming of chemoresistance via modulation of lncRNAs. Drug Resistance Updates 50:100683.

    Not in our library10.1016/j.drup.2020.100683

  125. 125.

    Jiang Z. Hsu J. L. Li Y. Hortobagyi G. N. Hung M.-C. (2020 ). Cancer cell metabolism bolsters immunotherapy resistance by promoting an immunosuppressive tumor microenvironment. Front. Oncol. 10:1197.

    Not in our library10.3389/fonc.2020.01197

  126. 126.
  127. 127.

    Jinushi M. Chiba S. Yoshiyama H. Masutomi K. Kinoshita I. Dosaka-Akita H. (2011 ). Tumor-associated macrophages regulate tumorigenicity and anticancer drug responses of cancer stem/initiating cells. Proc. Natl. Acad. Sci. U.S.A. 108 12425–12430.

    Not in our library10.1073/pnas.1106645108

  128. 128.

    Jo Y. Choi N. Kim K. Koo H. J. Choi J. Kim H. N. (2018 ). Chemoresistance of cancer cells: requirements of tumor microenvironment-mimicking in vitro models in anti-cancer drug development. Theranostics 8 5259–5275.

    Not in our library10.7150/thno.29098

  129. 129.

    Joyce J. A. (2005 ). Therapeutic targeting of the tumor microenvironment. Cancer Cell 7 513–520.

    Not in our library10.1016/j.ccr.2005.05.024

  130. 130.

    Kalluri R. Zeisberg M. (2006 ). Fibroblasts in cancer. Nat. Rev. Cancer 6 392–401.

    Not in our library10.1038/nrc1877

  131. 131.

    Kamphorst J. J. Cross J. R. Fan J. de Stanchina E. Mathew R. White E. P. (2013 ). Hypoxic and Ras-transformed cells support growth by scavenging unsaturated fatty acids from lysophospholipids. Proc. Natl. Acad. Sci. U.S.A. 110 8882–8887.

    Not in our library10.1073/pnas.1307237110

  132. 132.

    Kanazawa Y. Yamada T. Fujita I. Kakinuma D. Matsuno K. Arai H. (2017 ). In vitro chemosensitivity test for gastric cancer specimens predicts effectiveness of oxaliplatin and 5-fluorouracil. Anticancer Res. 37 6401–6405.

    Not in our library10.21873/anticanres.12093

  133. 133.

    Kang I. Harten I. A. Chang M. Y. Braun K. R. Sheih A. Nivison M. P. (2017 ). Versican deficiency significantly reduces lung inflammatory response induced by polyinosine-polycytidylic acid stimulation. J. Biol. Chem. 292 51–63.

    Not in our library10.1074/jbc.m116.753186

  134. 134.

    Kechagia J. Z. Ivaska J. Roca-Cusachs P. (2019 ). Integrins as biomechanical sensors of the microenvironment. Nat. Rev. Mol. Cell Biol. 20 457–473.

    Not in our library10.1038/s41580-019-0134-2

  135. 135.

    Kesh K. Gupta V. K. Durden B. Garrido V. Mateo-Victoriano B. Lavania S. P. (2020 ). Therapy resistance, cancer stem cells and ECM in cancer: the matrix reloaded. Cancers 12:3067.

    Not in our library10.3390/cancers12103067

  136. 136.

    Kim B. H. Yi E. H. Ye S. K. (2016 ). Signal transducer and activator of transcription 3 as a therapeutic target for cancer and the tumor microenvironment. Arch. Pharm Res. 39 1085–1099.

    Not in our library10.1007/s12272-016-0795-8

  137. 137.

    Kim K. Skora A. D. Li Z. Liu Q. Tam A. J. Blosser R. L. (2014 ). Eradication of metastatic mouse cancers resistant to immune checkpoint blockade by suppression of myeloid-derived cells. Proc. Natl. Acad. Sci. U.S.A. 111 11774–11779.

    Not in our library10.1073/pnas.1410626111

  138. 138.
  139. 139.

    Kinoshita M. Johnson D. L. Shatney C. H. Lee Y. L. Mochizuki H. (2001 ). Cancer cells surviving hypoxia obtain hypoxia resistance and maintain anti-apoptotic potential under reoxygenation. Int. J. Cancer 91 322–326.

    Not in our library10.1002/1097-0215(200002)9999:9999<::aid-ijc1064>3.0.co;2-p

  140. 140.

    Kitange G. J. Carlson B. L. Schroeder M. A. Grogan P. T. Lamont J. D. Decker P. A. (2009 ). Induction of MGMT expression is associated with temozolomide resistance in glioblastoma xenografts. Neuro Oncol. 11 281–291.

    Not in our library10.1215/15228517-2008-090

  141. 141.

    Klemm F. Joyce J. A. (2015 ). Microenvironmental regulation of therapeutic response in cancer. Trends Cell Biol. 25 198–213.

    Not in our library10.1016/j.tcb.2014.11.006

  142. 142.

    Kojima Y. Acar A. Eaton E. N. Mellody K. T. Scheel C. Ben-Porath I. (2010 ). Autocrine TGF-β and stromal cell-derived factor-1 (SDF-1) signaling drives the evolution of tumor-promoting mammary stromal myofibroblasts. Proc. Natl. Acad. Sci. 107 20009–20014.

    Not in our library10.1073/pnas.1013805107

  143. 143.

    Kolosenko I. Avnet S. Baldini N. Viklund J. De Milito A. (2017 ). Therapeutic implications of tumor interstitial acidification. Semin. Cancer Biol. 43 119–133.

    Not in our library10.1016/j.semcancer.2017.01.008

  144. 144.

    Korneev K. V. Atretkhany K.-S. N. Drutskaya M. S. Grivennikov S. I. Kuprash D. V. Nedospasov S. A. (2017 ). TLR-signaling and proinflammatory cytokines as drivers of tumorigenesis. Cytokine 89 127–135.

    Not in our library10.1016/j.cyto.2016.01.021

  145. 145.

    Kovacic P. Osuna J. A. Jr. (2000 ). Mechanisms of anti-cancer agents: emphasis on oxidative stress and electron transfer. Curr. Pharm. Des. 6 277–309.

    Not in our library10.2174/1381612003401046

  146. 146.
  147. 147.
  148. 148.
  149. 149.

    Larkin J. Chiarion-Sileni V. Gonzalez R. Grob J. J. Cowey C. L. Lao C. D. (2015 ). Combined nivolumab and ipilimumab or monotherapy in untreated melanoma. N. Engl. J. Med. 373 23–34.

    Not in our library10.1056/nejmoa1504030

  150. 150.

    Layani-Bazar A. Skornick I. Berrebi A. Pauker M. H. Noy E. Silberman A. (2014 ). Redox modulation of adjacent thiols in VLA-4 by AS101 converts myeloid leukemia cells from a drug-resistant to drug-sensitive state. Cancer Res. 74 3092–3103.

    Not in our library10.1158/0008-5472.can-13-2159

  151. 151.

    Lee C.-T. Boss M.-K. Dewhirst M. W. (2014 ). Imaging tumor hypoxia to advance radiation oncology. Antioxidants Redox Signal. 21 313–337.

    Not in our library10.1089/ars.2013.5759

  152. 152.

    Lee J. G. Wu R. (2015 ). Erlotinib-cisplatin combination inhibits growth and angiogenesis through c-MYC and HIF-1α in EGFR-mutated lung cancer in vitro and in vivo. Neoplasia 17 190–200.

    Not in our library10.1016/j.neo.2014.12.008

  153. 153.

    Lee P. Chandel N. S. Simon M. C. (2020 ). Cellular adaptation to hypoxia through hypoxia inducible factors and beyond. Nat. Rev. Mol. Cell Biol. 21 268–283.

    Not in our library10.1038/s41580-020-0227-y

  154. 154.

    Lei X. Lei Y. Li J.-K. Du W.-X. Li R.-G. Yang J. (2020 ). Immune cells within the tumor microenvironment: biological functions and roles in cancer immunotherapy. Cancer Lett. 470 126–133.

    Not in our library10.1016/j.canlet.2019.11.009

  155. 155.

    Leone R. D. Zhao L. Englert J. M. Sun I. M. Oh M. H. Sun I. H. (2019 ). Glutamine blockade induces divergent metabolic programs to overcome tumor immune evasion. Science 366 1013–1021.

    Not in our library10.1126/science.aav2588

  156. 156.

    Leu A. J. Berk D. A. Lymboussaki A. Alitalo K. Jain R. K. (2000 ). Absence of functional lymphatics within a murine sarcoma: a molecular and functional evaluation. Cancer Res. 60 4324–4327.

    Not in our library

  157. 157.

    Levchenko A. Mehta B. M. Niu X. Kang G. Villafania L. Way D. (2005 ). Intercellular transfer of P-glycoprotein mediates acquired multidrug resistance in tumor cells. Proc. Natl. Acad. Sci. U.S.A. 102 1933–1938.

    Not in our library10.1073/pnas.0401851102

  158. 158.

    Li W. Sun X. (2018 ). Recent advances in developing novel anti-cancer drugs targeting tumor hypoxic and acidic microenvironments. Recent Pat Anticancer Drug Discov. 13 455–468.

    Not in our library10.2174/1574892813666180831102519

  159. 159.

    Lin S. Negulescu A. Bulusu S. Gibert B. Delcros J.-G. Ducarouge B. (2017 ). Non-canonical NOTCH3 signalling limits tumour angiogenesis. Nat. Commun. 8 1–12.

    Not in our library10.1038/ncomms16074

  160. 160.
  161. 161.

    Ling B. Watt K. Banerjee S. Newsted D. Truesdell P. Adams J. (2017 ). A novel immunotherapy targeting MMP-14 limits hypoxia, immune suppression and metastasis in triple-negative breast cancer models. Oncotarget 8 58372–58385.

    Not in our library10.18632/oncotarget.17702

  162. 162.
  163. 163.

    Liu J. Liao S. Diop-Frimpong B. Chen W. Goel S. Naxerova K. (2012 ). TGF-β blockade improves the distribution and efficacy of therapeutics in breast carcinoma by normalizing the tumor stroma. Proc. Natl. Acad. Sci. U.S.A. 109 16618–16623.

    Not in our library10.1073/pnas.1117610109

  164. 164.

    Liu R. Fernandez-Peñas P. Sebaratnam D. F. (2017 ). Management of adverse events related to new cancer immunotherapy (immune checkpoint inhibitors). Med. J. Aust. 206:412.

    Not in our library10.5694/mja16.01357

  165. 165.
  166. 166.

    Lobb R. J. van Amerongen R. Wiegmans A. Ham S. Larsen J. E. Möller A. (2017 ). Exosomes derived from mesenchymal non-small cell lung cancer cells promote chemoresistance. Int. J. Cancer 141 614–620.

    Not in our library10.1002/ijc.30752

  167. 167.

    Löffek S. (2018 ). Transforming of the tumor microenvironment: implications for TGF-β inhibition in the context of immune-checkpoint therapy. J. Oncol. 2018:9732939.

    Not in our library10.1155/2018/9732939

  168. 168.

    Long L. Assaraf Y. G. Lei Z.-N. Peng H. Yang L. Chen Z.-S. (2020 ). Genetic biomarkers of drug resistance: a compass of prognosis and targeted therapy in acute myeloid leukemia. Drug Resistance Updates 52:100703.

    Not in our library10.1016/j.drup.2020.100703

  169. 169.

    Lotti F. Jarrar A. M. Pai R. K. Hitomi M. Lathia J. Mace A. (2013 ). Chemotherapy activates cancer-associated fibroblasts to maintain colorectal cancer-initiating cells by IL-17A. J. Exp. Med. 210 2851–2872.

    Not in our library10.1084/jem.20131195

  170. 170.

    Lu C. W. Lin S. C. Chien C. W. Lin S. C. Lee C. T. Lin B. W. (2011 ). Overexpression of pyruvate dehydrogenase kinase 3 increases drug resistance and early recurrence in colon cancer. Am. J. Pathol. 179 1405–1414.

    Not in our library10.1016/j.ajpath.2011.05.050

  171. 171.

    Luga V. Zhang L. Viloria-Petit A. M. Ogunjimi A. A. Inanlou M. R. Chiu E. (2012 ). Exosomes mediate stromal mobilization of autocrine Wnt-PCP signaling in breast cancer cell migration. Cell 151 1542–1556.

    Not in our library10.1016/j.cell.2012.11.024

  172. 172.

    Luo W. Zhong J. Chang R. Hu H. Pandey A. Semenza G. L. (2010 ). Hsp70 and CHIP selectively mediate ubiquitination and degradation of hypoxia-inducible factor (HIF)-1alpha but Not HIF-2alpha. J. Biol. Chem. 285 3651–3663.

    Not in our library10.1074/jbc.m109.068577

  173. 173.

    Luraghi P. Reato G. Cipriano E. Sassi F. Orzan F. Bigatto V. (2014 ). MET signaling in colon cancer stem-like cells blunts the therapeutic response to EGFR inhibitors. Cancer Res. 74 1857–1869.

    Not in our library10.1158/0008-5472.can-13-2340-t

  174. 174.

    Lv M. M. Zhu X. Y. Chen W. X. Zhong S. L. Hu Q. Ma T. F. (2014 ). Exosomes mediate drug resistance transfer in MCF-7 breast cancer cells and a probable mechanism is delivery of P-glycoprotein. Tumour. Biol. 35 10773–10779.

    Not in our library10.1007/s13277-014-2377-z

  175. 175.

    Ma Z. Yuan D. Cheng X. Tuo B. Liu X. Li T. (2020 ). Function of ion transporters in maintaining acid-base homeostasis of the mammary gland and the pathophysiological role in breast cancer. Am. J. Physiol. Regul. Integr. Comp. Physiol. 318 R98–R111.

    Not in our library10.1152/ajpregu.00202.2019

  176. 176.
  177. 177.

    Maj T. Wang W. Crespo J. Zhang H. Wang W. Wei S. (2017 ). Oxidative stress controls regulatory T cell apoptosis and suppressor activity and PD-L1-blockade resistance in tumor. Nat. Immunol. 18 1332–1341.

    Not in our library10.1038/ni.3868

  178. 178.

    Maman S. Witz I. P. (2018 ). A history of exploring cancer in context. Nat. Rev. Cancer 18 359–376.

    Not in our library10.1038/s41568-018-0006-7

  179. 179.

    Mangan M. S. Vega-Ramos J. Joeckel L. T. Mitchell A. J. Rizzitelli A. Roediger B. (2017 ). Serpinb9 is a marker of antigen cross-presenting dendritic cells. Mol. Immunol. 82 50–56.

    Not in our library10.1016/j.molimm.2016.12.011

  180. 180.

    Manning B. D. Cantley L. C. (2007 ). AKT/PKB signaling: navigating downstream. Cell 129 1261–1274.

    Not in our library10.1016/j.cell.2007.06.009

  181. 181.

    Mantoni T. S. Lunardi S. Al-Assar O. Masamune A. Brunner T. B. (2011 ). Pancreatic stellate cells radioprotect pancreatic cancer cells through β1-integrin signaling. Cancer Res. 71 3453–3458.

    Not in our library10.1158/0008-5472.can-10-1633

  182. 182.

    Mantovani A. Allavena P. Sica A. Balkwill F. (2008 ). Cancer-related inflammation. Nature 454 436–444.

    Not in our library10.1038/nature07205

  183. 183.

    Mantovani A. Marchesi F. Malesci A. Laghi L. Allavena P. (2017 ). Tumour-associated macrophages as treatment targets in oncology. Nat. Rev. Clin. Oncol. 14 399–416.

    Not in our library10.1038/nrclinonc.2016.217

  184. 184.

    Martínez-Lostao L. Anel A. Pardo J. (2015 ). How do cytotoxic lymphocytes kill cancer cells? Clin. Cancer Res, 21 5047–5056.

    Not in our library10.1158/1078-0432.ccr-15-0685

  185. 185.

    Martinez-Outschoorn U. E. Peiris-Pagés M. Pestell R. G. Sotgia F. Lisanti M. P. (2017 ). Cancer metabolism: a therapeutic perspective. Nat. Rev. Clin. Oncol. 14 11–31.

    Not in our library10.1038/nrclinonc.2016.60

  186. 186.

    Martinkova E. Maglott A. Leger D. Y. Bonnet D. Stiborova M. Takeda K. (2010 ). α5β1 integrin antagonists reduce chemotherapy-induced premature senescence and facilitate apoptosis in human glioblastoma cells. Int. J. Cancer 127 1240–1248.

    Not in our library10.1002/ijc.25187

  187. 187.

    Martino M. M. Briquez P. S. Güç E. Tortelli F. Kilarski W. W. Metzger S. (2014 ). Growth factors engineered for super-affinity to the extracellular matrix enhance tissue healing. Science 343 885–888.

    Not in our library10.1126/science.1247663

  188. 188.
  189. 189.

    Matsunuma S. Handa S. Kamei D. Yamamoto H. Okuyama K. Kato Y. (2019 ). Oxaliplatin induces prostaglandin E2 release in vascular endothelial cells. Cancer Chemother. Pharmacol. 84 345–350.

    Not in our library10.1007/s00280-019-03901-7

  190. 190.

    Mazzarella L. Curigliano G. (2018 ). A new approach to assess drug sensitivity in cells for novel drug discovery. Expert Opin. Drug Discov. 13 339–346.

    Not in our library10.1080/17460441.2018.1437136

  191. 191.

    McAndrews K. M. McGrail D. J. Ravikumar N. Dawson M. R. (2015 ). Mesenchymal stem cells induce directional migration of invasive breast cancer cells through TGF-β. Sci. Rep. 5:16941.

    Not in our library10.1038/srep16941

  192. 192.

    Meijer T. W. Kaanders J. H. Span P. N. Bussink J. (2012 ). Targeting hypoxia, HIF-1, and tumor glucose metabolism to improve radiotherapy efficacy. Clin. Cancer Res. 18 5585–5594.

    Not in our library10.1158/1078-0432.ccr-12-0858

  193. 193.

    Meurette O. Mehlen P. (2018 ). Notch signaling in the tumor microenvironment. Cancer Cell 34 536–548.

    Not in our library10.1016/j.ccell.2018.07.009

  194. 194.

    Miller K. D. Nogueira L. Mariotto A. B. Rowland J. H. Yabroff K. R. Alfano C. M. (2019 ). Cancer treatment and survivorship statistics, 2019. CA Cancer J. Clin. 69 363–385.

    Not in our library10.3322/caac.21565

  195. 195.

    Milman N. Ginini L. Gil Z. (2019 ). Exosomes and their role in tumorigenesis and anticancer drug resistance. Drug Resistance Updates 45 1–12.

    Not in our library10.1016/j.drup.2019.07.003

  196. 196.

    Milosevic M. Fyles A. Hedley D. Hill R. (2004 ). The human tumor microenvironment: invasive (needle) measurement of oxygen and interstitial fluid pressure. Semin. Radiat. Oncol. 14 249–258.

    Not in our library10.1016/j.semradonc.2004.04.006

  197. 197.

    Mohammad R. M. Muqbil I. Lowe L. Yedjou C. Hsu H. Y. Lin L. T. (2015 ). Broad targeting of resistance to apoptosis in cancer. Semin. Cancer Biol. 35(Suppl.(0)), S78–S103.

    Not in our library10.1016/j.semcancer.2015.03.001

  198. 198.

    Moloney J. N. Cotter T. G. (2018 ). ROS signalling in the biology of cancer. Semin. Cell Dev. Biol. 80 50–64.

    Not in our library10.1016/j.semcdb.2017.05.023

  199. 199.

    Monferran S. Skuli N. Delmas C. Favre G. Bonnet J. Cohen-Jonathan-Moyal E. (2008 ). αvβ3 and αvβ5 integrins control glioma cell response to ionising radiation through ILK and RhoB. Int. J. Cancer 123 357–364.

    Not in our library10.1002/ijc.23498

  200. 200.

    Morrot A. da Fonseca L. M. Salustiano E. J. Gentile L. B. Conde L. Filardy A. A. (2018 ). Metabolic symbiosis and immunomodulation: how tumor cell-derived lactate may disturb innate and adaptive immune responses. Front. Oncol. 8:81.

    Not in our library10.3389/fonc.2018.00081

  201. 201.

    Morrow K. Hernandez C. P. Raber P. Del Valle L. Wilk A. M. Majumdar S. (2013 ). Anti-leukemic mechanisms of pegylated arginase I in acute lymphoblastic T-cell leukemia. Leukemia 27 569–577.

    Not in our library10.1038/leu.2012.247

  202. 202.

    Nagaraj S. Gupta K. Pisarev V. Kinarsky L. Sherman S. Kang L. (2007 ). Altered recognition of antigen is a mechanism of CD8+ T cell tolerance in cancer. Nat. Med. 13 828–835.

    Not in our library10.1038/nm1609

  203. 203.

    Nagathihalli N. S. Castellanos J. A. Shi C. Beesetty Y. Reyzer M. L. Caprioli R. (2015 ). Signal transducer and activator of transcription 3, mediated remodeling of the tumor microenvironment results in enhanced tumor drug delivery in a mouse model of pancreatic cancer. Gastroenterology 149 1932.e9–1943.e9.

    Not in our library10.1053/j.gastro.2015.07.058

  204. 204.

    Najafi M. Farhood B. Mortezaee K. (2019 ). Extracellular matrix (ECM) stiffness and degradation as cancer drivers. J. Cell Biochem. 120 2782–2790.

    Not in our library10.1002/jcb.27681

  205. 205.

    Nishimoto A. Kugimiya N. Hosoyama T. Enoki T. Li T. S. Hamano K. (2014 ). HIF-1α activation under glucose deprivation plays a central role in the acquisition of anti-apoptosis in human colon cancer cells. Int. J. Oncol. 44 2077–2084.

    Not in our library10.3892/ijo.2014.2367

  206. 206.

    Nokin M. J. Durieux F. Bellier J. Peulen O. Uchida K. Spiegel D. A. (2017 ). Hormetic potential of methylglyoxal, a side-product of glycolysis, in switching tumours from growth to death. Sci. Rep. 7:11722.

    Not in our library10.1038/s41598-017-12119-7

  207. 207.

    Noy R. Pollard J. W. (2014 ). Tumor-associated macrophages: from mechanisms to therapy. Immunity 41 49–61.

    Not in our library10.1016/j.immuni.2014.06.010

  208. 208.

    Obenauf A. C. Zou Y. Ji A. L. Vanharanta S. Shu W. Shi H. (2015 ). Therapy-induced tumour secretomes promote resistance and tumour progression. Nature 520 368–372.

    Not in our library10.1038/nature14336

  209. 209.

    O’Donnell J. S. Long G. V. Scolyer R. A. Teng M. W. L. Smyth M. J. (2017 ). Resistance to PD1/PDL1 checkpoint inhibition. Cancer Treatm. Rev. 52 71–81.

    Not in our library10.1016/j.ctrv.2016.11.007

  210. 210.

    Ogawa R. Ishiguro H. Kuwabara Y. Kimura M. Mitsui A. Mori Y. (2008 ). Identification of candidate genes involved in the radiosensitivity of esophageal cancer cells by microarray analysis. Dis. Esophagus 21 288–297.

    Not in our library10.1111/j.1442-2050.2007.00759.x

  211. 211.

    Oh M. H. Sun I. H. Zhao L. Leone R. D. Sun I. M. Xu W. (2020 ). Targeting glutamine metabolism enhances tumor-specific immunity by modulating suppressive myeloid cells. J. Clin. Invest. 130 3865–3884.

    Not in our library10.1172/jci131859

  212. 212.

    Olive K. P. Jacobetz M. A. Davidson C. J. Gopinathan A. McIntyre D. Honess D. (2009 ). Inhibition of Hedgehog signaling enhances delivery of chemotherapy in a mouse model of pancreatic cancer. Science 324 1457–1461.

    Not in our library10.1126/science.1171362

  213. 213.

    Orimo A. Gupta P. B. Sgroi D. C. Arenzana-Seisdedos F. Delaunay T. Naeem R. (2005 ). Stromal fibroblasts present in invasive human breast carcinomas promote tumor growth and angiogenesis through elevated SDF-1/CXCL12 secretion. Cell 121 335–348.

    Not in our library10.1016/j.cell.2005.02.034

  214. 214.

    O’Sullivan D. van der Windt G. J. Huang S. C. Curtis J. D. Chang C. H. Buck M. D. (2014 ). Memory CD8(+) T cells use cell-intrinsic lipolysis to support the metabolic programming necessary for development. Immunity 41 75–88.

    Not in our library10.1016/j.immuni.2014.06.005

  215. 215.
  216. 216.

    Ozawa P. M. M. Alkhilaiwi F. Cavalli I. J. Malheiros D. de Souza Fonseca Ribeiro E. M. Cavalli L. R. (2018 ). Extracellular vesicles from triple-negative breast cancer cells promote proliferation and drug resistance in non-tumorigenic breast cells. Breast Cancer Res. Treat. 172 713–723.

    Not in our library10.1007/s10549-018-4925-5

  217. 217.

    Paauwe M. Schoonderwoerd M. J. Helderman R. F. Harryvan T. J. Groenewoud A. van Pelt G. W. (2018 ). Endoglin expression on cancer-associated fibroblasts regulates invasion and stimulates colorectal cancer metastasis. Clin. Cancer Res. 24 6331–6344.

    Not in our library10.1158/1078-0432.ccr-18-0329

  218. 218.

    Padera T. P. Stoll B. R. Tooredman J. B. Capen D. di Tomaso E. Jain R. K. (2004 ). Cancer cells compress intratumour vessels. Nature 427 695–695.

    Not in our library10.1038/427695a

  219. 219.

    Paolicchi E. Gemignani F. Krstic-Demonacos M. Dedhar S. Mutti L. Landi S. (2016 ). Targeting hypoxic response for cancer therapy. Oncotarget 7 13464–13478.

    Not in our library10.18632/oncotarget.7229

  220. 220.

    Paolillo M. Schinelli S. (2017 ). Integrins and exosomes, a dangerous liaison in cancer progression. Cancers 9:95.

    Not in our library10.3390/cancers9080095

  221. 221.

    Papapetrou E. P. (2016 ). Patient-derived induced pluripotent stem cells in cancer research and precision oncology. Nat. Med. 22 1392–1401.

    Not in our library10.1038/nm.4238

  222. 222.

    Park C. C. Zhang H. J. Yao E. S. Park C. J. Bissell M. J. (2008 ). β1Integrin inhibition dramatically enhances radiotherapy efficacy in human breast cancer xenografts. Cancer Res. 68 4398–4405.

    Not in our library10.1158/0008-5472.can-07-6390

  223. 223.

    Patel S. A. Minn A. J. (2018 ). Combination cancer therapy with immune checkpoint blockade: mechanisms and strategies. Immunity 48 417–433.

    Not in our library10.1016/j.immuni.2018.03.007

  224. 224.

    Paz-Ares L. Garon E. Ardizzoni A. Barlesi F. Cho B. de Castro Junior G. (2019 ). CANOPY phase III program: three studies evaluating canakinumab in patients with non-small cell lung cancer (NSCLC). Ann. Oncol. 30 v654–v655.

    Not in our library

  225. 225.

    Pei G. T. Wu C. W. Lin W. W. (2010 ). Hypoxia-induced decoy receptor 2 gene expression is regulated via a hypoxia-inducible factor 1alpha-mediated mechanism. Biochem. Biophys. Res. Commun. 391 1274–1279.

    Not in our library10.1016/j.bbrc.2009.12.058

  226. 226.
  227. 227.

    Pickup M. W. Mouw J. K. Weaver V. M. (2014 ). The extracellular matrix modulates the hallmarks of cancer. EMBO Rep. 15 1243–1253.

    Not in our library10.15252/embr.201439246

  228. 228.

    Podar K. Zimmerhackl A. Fulciniti M. Tonon G. Hainz U. Tai Y. T. (2011 ). The selective adhesion molecule inhibitor Natalizumab decreases multiple myeloma cell growth in the bone marrow microenvironment: therapeutic implications. Br. J. Haematol. 155 438–448.

    Not in our library10.1111/j.1365-2141.2011.08864.x

  229. 229.

    Pouysségur J. Dayan F. Mazure N. M. (2006 ). Hypoxia signalling in cancer and approaches to enforce tumour regression. Nature 441 437–443.

    Not in our library10.1038/nature04871

  230. 230.

    Prima V. Kaliberova L. N. Kaliberov S. Curiel D. T. Kusmartsev S. (2017 ). COX2/mPGES1/PGE2 pathway regulates PD-L1 expression in tumor-associated macrophages and myeloid-derived suppressor cells. Proc. Natl. Acad. Sci. U.S.A. 114 1117–1122.

    Not in our library10.1073/pnas.1612920114

  231. 231.

    Pucino V. Bombardieri M. Pitzalis C. Mauro C. (2017 ). Lactate at the crossroads of metabolism, inflammation, and autoimmunity. Eur. J. Immunol. 47 14–21.

    Not in our library10.1002/eji.201646477

  232. 232.

    Purcell J. W. Tanlimco S. G. Hickson J. Fox M. Sho M. Durkin L. (2018 ). LRRC15 is a novel mesenchymal protein and stromal target for antibody-drug conjugates. Cancer Res. 78 4059–4072.

    Not in our library10.1158/0008-5472.can-18-0327

  233. 233.

    Pusch S. Krausert S. Fischer V. Balss J. Ott M. Schrimpf D. (2017 ). Pan-mutant IDH1 inhibitor BAY 1436032 for effective treatment of IDH1 mutant astrocytoma in vivo. Acta Neuropathol. 133 629–644.

    Not in our library10.1007/s00401-017-1677-y

  234. 234.

    Qiao Y. Zhang C. Li A. Wang D. Luo Z. Ping Y. (2018 ). IL6 derived from cancer-associated fibroblasts promotes chemoresistance via CXCR7 in esophageal squamous cell carcinoma. Oncogene 37 873–883.

    Not in our library10.1038/onc.2017.387

  235. 235.

    Quail D. F. Joyce J. A. (2013 ). Microenvironmental regulation of tumor progression and metastasis. Nat. Med. 19 1423–1437.

    Not in our library10.1038/nm.3394

  236. 236.

    Raghunand N. Mahoney B. P. Gillies R. J. (2003 ). Tumor acidity, ion trapping and chemotherapeutics. II. pH-dependent partition coefficients predict importance of ion trapping on pharmacokinetics of weakly basic chemotherapeutic agents. Biochem. Pharmacol. 66 1219–1229.

    Not in our library10.1016/s0006-2952(03)00468-4

  237. 237.

    Räihä M. R. Puolakkainen P. A. (2018 ). Tumor-associated macrophages (TAMs) as biomarkers for gastric cancer: a review. Chronic Dis. Transl. Med. 4 156–163.

    Not in our library10.1016/j.cdtm.2018.07.001

  238. 238.

    Ramapriyan R. Caetano M. S. Barsoumian H. B. Mafra A. C. P. Zambalde E. P. Menon H. (2019 ). Altered cancer metabolism in mechanisms of immunotherapy resistance. Pharmacol. Ther. 195 162–171.

    Not in our library10.1016/j.pharmthera.2018.11.004

  239. 239.

    Räsänen K. Vaheri A. (2010 ). Activation of fibroblasts in cancer stroma. Exp. Cell Res. 316 2713–2722.

    Not in our library10.1016/j.yexcr.2010.04.032

  240. 240.

    Ren J. Ding L. Zhang D. Shi G. Xu Q. Shen S. (2018 ). Carcinoma-associated fibroblasts promote the stemness and chemoresistance of colorectal cancer by transferring exosomal lncRNA H19. Theranostics 8:3932.

    Not in our library10.7150/thno.25541

  241. 241.

    Restifo N. P. Smyth M. J. Snyder A. (2016 ). Acquired resistance to immunotherapy and future challenges. Nat. Rev. Cancer 16 121–126.

    Not in our library10.1038/nrc.2016.2

  242. 242.

    Richards K. E. Zeleniak A. E. Fishel M. L. Wu J. Littlepage L. E. Hill R. (2017 ). Cancer-associated fibroblast exosomes regulate survival and proliferation of pancreatic cancer cells. Oncogene 36 1770–1778.

    Not in our library10.1038/onc.2016.353

  243. 243.

    Ridker P. M. MacFadyen J. G. Thuren T. Everett B. M. Libby P. Glynn R. J. (2017 ). Effect of interleukin-1β inhibition with canakinumab on incident lung cancer in patients with atherosclerosis: exploratory results from a randomised, double-blind, placebo-controlled trial. Lancet 390 1833–1842.

    Not in our library10.1016/s0140-6736(17)32247-x

  244. 244.

    Ritter V. (2017 ). Role of Bcl-2 Protein Family Members and Associated Mitochondrial Factors in Hypoxia-Mediated Resistance of Tumor Cells to Apoptosis and Radiotherapy. Duisburg: Universität Duisburg-Essen.

    Not in our library

  245. 245.

    Robert C. Schachter J. Long G. V. Arance A. Grob J. J. Mortier L. (2015 ). Pembrolizumab versus ipilimumab in advanced melanoma. N. Engl. J. Med. 372 2521–2532.

    Not in our library10.1056/nejmoa1503093

  246. 246.
  247. 247.
  248. 248.

    Roswall P. Bocci M. Bartoschek M. Li H. Kristiansen G. Jansson S. (2018 ). Microenvironmental control of breast cancer subtype elicited through paracrine platelet-derived growth factor-CC signaling. Nat. Med. 24 463–473.

    Not in our library10.1038/nm.4494

  249. 249.

    Ruffell B. Coussens L. M. (2015 ). Macrophages and therapeutic resistance in cancer. Cancer Cell 27 462–472.

    Not in our library10.1016/j.ccell.2015.02.015

  250. 250.

    Safaei R. Larson B. J. Cheng T. C. Gibson M. A. Otani S. Naerdemann W. (2005 ). Abnormal lysosomal trafficking and enhanced exosomal export of cisplatin in drug-resistant human ovarian carcinoma cells. Mol. Cancer Ther. 4 1595–1604.

    Not in our library10.1158/1535-7163.mct-05-0102

  251. 251.

    Saleh R. Elkord E. (2020 ). Acquired resistance to cancer immunotherapy: role of tumor-mediated immunosuppression. Semin. Cancer Biol. 65 13–27.

    Not in our library10.1016/j.semcancer.2019.07.017

  252. 252.

    Salmaninejad A. Valilou S. F. Soltani A. Ahmadi S. Abarghan Y. J. Rosengren R. J. (2019 ). Tumor-associated macrophages: role in cancer development and therapeutic implications. Cell Oncol. 42 591–608.

    Not in our library10.1007/s13402-019-00453-z

  253. 253.

    Salnikov A. V. Iversen V. V. Koisti M. Sundberg C. Johansson L. Stuhr L. B. (2003 ). Lowering of tumor interstitial fluid pressure specifically augments efficacy of chemotherapy. FASEB J. 17 1756–1758.

    Not in our library10.1096/fj.02-1201fje

  254. 254.

    Salony, Solé X. Alves C. P. Dey-Guha I. Ritsma L. Boukhali M. (2016 ). AKT inhibition promotes nonautonomous cancer cell survival. Mol. Cancer Ther. 15 142–153.

    Not in our library10.1158/1535-7163.mct-15-0414

  255. 255.

    Salvagno C. Ciampricotti M. Tuit S. Hau C.-S. van Weverwijk A. Coffelt S. B. (2019 ). Therapeutic targeting of macrophages enhances chemotherapy efficacy by unleashing type I interferon response. Nat. Cell Biol. 21 511–521.

    Not in our library10.1038/s41556-019-0298-1

  256. 256.

    Samavati L. Rastogi R. Du W. Hüttemann M. Fite A. Franchi L. (2009 ). STAT3 tyrosine phosphorylation is critical for interleukin 1 beta and interleukin-6 production in response to lipopolysaccharide and live bacteria. Mol. Immunol. 46 1867–1877.

    Not in our library10.1016/j.molimm.2009.02.018

  257. 257.

    Sato N. Kohi S. Hirata K. Goggins M. (2016 ). Role of hyaluronan in pancreatic cancer biology and therapy: once again in the spotlight. Cancer Sci. 107 569–575.

    Not in our library10.1111/cas.12913

  258. 258.

    Sauvant C. Nowak M. Wirth C. Schneider B. Riemann A. Gekle M. (2008 ). Acidosis induces multi-drug resistance in rat prostate cancer cells (AT1) in vitro and in vivo by increasing the activity of the p-glycoprotein via activation of p38. Int. J. Cancer 123 2532–2542.

    Not in our library10.1002/ijc.23818

  259. 259.
  260. 260.

    Scalici J. M. Harrer C. Allen A. Jazaeri A. Atkins K. A. McLachlan K. R. (2014 ). Inhibition of α4β1 integrin increases ovarian cancer response to carboplatin. Gynecol. Oncol. 132 455–461.

    Not in our library10.1016/j.ygyno.2013.12.031

  261. 261.

    Scannevin R. H. Alexander R. Haarlander T. M. Burke S. L. Singer M. Huo C. (2017 ). Discovery of a highly selective chemical inhibitor of matrix metalloproteinase-9 (MMP-9) that allosterically inhibits zymogen activation. J. Biol. Chem. 292 17963–17974.

    Not in our library10.1074/jbc.m117.806075

  262. 262.

    Schenk K. M. Reuss J. E. Choquette K. Spira A. I. (2019 ). A review of canakinumab and its therapeutic potential for non-small cell lung cancer. Anti Cancer Drugs 30 879–885.

    Not in our library10.1097/cad.0000000000000832

  263. 263.
  264. 264.

    Schrader J. Gordon-Walker T. T. Aucott R. L. van Deemter M. Quaas A. Walsh S. (2011 ). Matrix stiffness modulates proliferation, chemotherapeutic response, and dormancy in hepatocellular carcinoma cells. Hepatology 53 1192–1205.

    Not in our library10.1002/hep.24108

  265. 265.

    Seguin L. Kato S. Franovic A. Camargo M. F. Lesperance J. Elliott K. C. (2014 ). An integrin β 3–KRAS–RalB complex drives tumour stemness and resistance to EGFR inhibition. Nat. Biol. 16 457–468.

    Not in our library10.1038/ncb2953

  266. 266.

    Sehested T. S. Bjerre J. Ku S. Chang A. Jahansouz A. Owens D. K. (2019 ). Cost-effectiveness of Canakinumab for prevention of recurrent cardiovascular events. JAMA Cardiol. 4 128–135.

    Not in our library10.1001/jamacardio.2018.4566

  267. 267.

    Semenza G. L. (2013 ). Cancer–stromal cell interactions mediated by hypoxia-inducible factors promote angiogenesis, lymphangiogenesis, and metastasis. Oncogene 32 4057–4063.

    Not in our library10.1038/onc.2012.578

  268. 268.

    Senthebane D. A. Jonker T. Rowe A. Thomford N. E. Munro D. Dandara C. (2018 ). The role of tumor microenvironment in chemoresistance: 3D extracellular matrices as accomplices. Int. J. Mol. Sci. 19:2861.

    Not in our library10.3390/ijms19102861

  269. 269.

    Sevick E. M. Jain R. K. (1989 ). Geometric resistance to blood flow in solid tumors perfused ex vivo: effects of tumor size and perfusion pressure. Cancer Res. 49 3506–3512.

    Not in our library

  270. 270.

    Shackelford D. B. Vasquez D. S. Corbeil J. Wu S. Leblanc M. Wu C. L. (2009 ). mTOR and HIF-1alpha-mediated tumor metabolism in an LKB1 mouse model of Peutz-Jeghers syndrome. Proc. Natl. Acad. Sci. U.S.A. 106 11137–11142.

    Not in our library10.1073/pnas.0900465106

  271. 271.

    Shalabi H. Kraft I. L. Wang H. W. Yuan C. M. Yates B. Delbrook C. (2018 ). Sequential loss of tumor surface antigens following chimeric antigen receptor T-cell therapies in diffuse large B-cell lymphoma. Haematologica 103 e215–e218.

    Not in our library10.3324/haematol.2017.183459

  272. 272.

    Sharma P. Hu-Lieskovan S. Wargo J. A. Ribas A. (2017 ). Primary, adaptive, and acquired resistance to cancer immunotherapy. Cell 168 707–723.

    Not in our library10.1016/j.cell.2017.01.017

  273. 273.

    Shaw R. J. Bardeesy N. Manning B. D. Lopez L. Kosmatka M. DePinho R. A. (2004 ). The LKB1 tumor suppressor negatively regulates mTOR signaling. Cancer Cell 6 91–99.

    Not in our library10.1016/j.ccr.2004.06.007

  274. 274.

    Shayan G. Srivastava R. Li J. Schmitt N. Kane L. P. Ferris R. L. (2017 ). Adaptive resistance to anti-PD1 therapy by Tim-3 upregulation is mediated by the PI3K-Akt pathway in head and neck cancer. OncoImmunology 6:e1261779.

    Not in our library10.1080/2162402x.2016.1261779

  275. 275.

    Shedden K. Xie X. T. Chandaroy P. Chang Y. T. Rosania G. R. (2003 ). Expulsion of small molecules in vesicles shed by cancer cells: association with gene expression and chemosensitivity profiles. Cancer Res. 63 4331–4337.

    Not in our library

  276. 276.
  277. 277.

    Shree T. Olson O. C. Elie B. T. Kester J. C. Garfall A. L. Simpson K. (2011 ). Macrophages and cathepsin proteases blunt chemotherapeutic response in breast cancer. Genes Dev. 25 2465–2479.

    Not in our library10.1101/gad.180331.111

  278. 278.
  279. 279.

    Socinski M. A. Jotte R. M. Cappuzzo F. Orlandi F. Stroyakovskiy D. Nogami N. (2018 ). Atezolizumab for first-line treatment of metastatic nonsquamous NSCLC. N. Engl. J. Med. 378 2288–2301.

    Not in our library10.1056/nejmoa1716948

  280. 280.

    Solinas G. Schiarea S. Liguori M. Fabbri M. Pesce S. Zammataro L. (2010 ). Tumor-conditioned macrophages secrete migration-stimulating factor: a new marker for M2-polarization, influencing tumor cell motility. J. Immunol. 185 642–652.

    Not in our library10.4049/jimmunol.1000413

  281. 281.

    Steinbichler T. B. Dudás J. Skvortsov S. Ganswindt U. Riechelmann H. Skvortsova I. I. (2018 ). Therapy resistance mediated by cancer stem cells. Semin. Cancer Biol. 53 156–167.

    Not in our library10.1016/j.semcancer.2018.11.006

  282. 282.
  283. 283.

    Stepka P. Vsiansky V. Raudenska M. Gumulec J. Adam V. Masarik M. (2020 ). Metabolic and amino acid alterations of the tumor microenvironment. Curr. Med. Chem. 27:1.

    Not in our library10.2174/0929867327666200207114658

  284. 284.

    Stohrer M. Boucher Y. Stangassinger M. Jain R. K. (2000 ). Oncotic pressure in solid tumors is elevated. Cancer Res. 60 4251–4255.

    Not in our library

  285. 285.

    Stone M. L. Chiappinelli K. B. Li H. Murphy L. M. Travers M. E. Topper M. J. (2017 ). Epigenetic therapy activates type I interferon signaling in murine ovarian cancer to reduce immunosuppression and tumor burden. Proc. Natl. Acad. Sci. U.S.A. 114 E10981–E10990.

    Not in our library10.1073/pnas.1712514114

  286. 286.

    Straussman R. Morikawa T. Shee K. Barzily-Rokni M. Qian Z. R. Du J. (2012 ). Tumour micro-environment elicits innate resistance to RAF inhibitors through HGF secretion. Nature 487 500–504.

    Not in our library10.1038/nature11183

  287. 287.

    Strick R. Strissel P. L. Baylin S. B. Chiappinelli K. B. (2016 ). Unraveling the molecular pathways of DNA-methylation inhibitors: human endogenous retroviruses induce the innate immune response in tumors. Oncoimmunology 5:e1122160.

    Not in our library10.1080/2162402x.2015.1122160

  288. 288.

    Studebaker A. W. Storci G. Werbeck J. L. Sansone P. Sasser A. K. Tavolari S. (2008 ). Fibroblasts isolated from common sites of breast cancer metastasis enhance cancer cell growth rates and invasiveness in an interleukin-6–dependent manner. Cancer Res. 68 9087–9095.

    Not in our library10.1158/0008-5472.can-08-0400

  289. 289.

    Stupp R. Hegi M. E. Gorlia T. Erridge S. C. Perry J. Hong Y.-K. (2014 ). Cilengitide combined with standard treatment for patients with newly diagnosed glioblastoma with methylated MGMT promoter (CENTRIC EORTC 26071-22072 study): a multicentre, randomised, open-label, phase 3 trial. Lancet Oncol. 15 1100–1108.

    Not in our library10.1016/s1470-2045(14)70379-1

  290. 290.

    Su S. Chen J. Yao H. Liu J. Yu S. Lao L. (2018 ). CD10(+)GPR77(+) Cancer-associated fibroblasts promote cancer formation and chemoresistance by sustaining cancer stemness. Cell 172 841.e16–856.e16.

    Not in our library10.1016/j.cell.2018.01.009

  291. 291.

    Sun Y. (2016 ). Tumor microenvironment and cancer therapy resistance. Cancer Lett. 380 205–215.

    Not in our library10.1016/j.canlet.2015.07.044

  292. 292.

    Sun Y. Campisi J. Higano C. Beer T. M. Porter P. Coleman I. (2012 ). Treatment-induced damage to the tumor microenvironment promotes prostate cancer therapy resistance through WNT16B. Nat. Med. 18 1359–1368.

    Not in our library10.1038/nm.2890

  293. 293.
  294. 294.

    Supuran C. T. (2018 ). Carbonic anhydrase inhibitors as emerging agents for the treatment and imaging of hypoxic tumors. Expert Opin. Invest. Drugs 27 963–970.

    Not in our library10.1080/13543784.2018.1548608

  295. 295.

    Szakács G. Paterson J. K. Ludwig J. A. Booth-Genthe C. Gottesman M. M. (2006 ). Targeting multidrug resistance in cancer. Nat. Rev. Drug Discov. 5 219–234.

    Not in our library10.1038/nrd1984

  296. 296.

    Szebeni G. J. Vizler C. Nagy L. I. Kitajka K. Puskas L. G. (2016 ). pro-tumoral inflammatory myeloid cells as emerging therapeutic targets. Int. J. Mol. Sci. 17:1958.

    Not in our library10.3390/ijms17111958

  297. 297.

    Taipale M. Jarosz D. F. Lindquist S. (2010 ). HSP90 at the hub of protein homeostasis: emerging mechanistic insights. Nat. Rev. Mol. Cell Biol. 11 515–528.

    Not in our library10.1038/nrm2918

  298. 298.

    Tan H. Y. Wang N. Lam W. Guo W. Feng Y. Cheng Y. C. (2018 ). Targeting tumour microenvironment by tyrosine kinase inhibitor. Mol. Cancer 17:43.

    Not in our library10.1186/s12943-018-0800-6

  299. 299.

    Tan Q. Saggar J. K. Yu M. Wang M. Tannock I. F. (2015 ). Mechanisms of drug resistance related to the microenvironment of solid tumors and possible strategies to inhibit them. Cancer J. 21 254–262.

    Not in our library10.1097/ppo.0000000000000131

  300. 300.

    Tanaka H. Yoshizawa H. Yamaguchi Y. Ito K. Kagamu H. Suzuki E. (1999 ). Successful adoptive immunotherapy of murine poorly immunogenic tumor with specific effector cells generated from gene-modified tumor-primed lymph node cells. J. Immunol. 162 3574–3582.

    Not in our library

  301. 301.

    Tang Y. A. Chen Y. F. Bao Y. Mahara S. Yatim S. Oguz G. (2018 ). Hypoxic tumor microenvironment activates GLI2 via HIF-1α and TGF-β2 to promote chemoresistance in colorectal cancer. Proc. Natl. Acad. Sci. U.S.A. 115 E5990–E5999.

    Not in our library10.1073/pnas.1801348115

  302. 302.

    Tatum J. L. (2006 ). Hypoxia: importance in tumor biology, noninvasive measurement by imaging, and value of its measurement in the management of cancer therapy. Int. J. Radiat. Biol. 82 699–757.

    Not in our library10.1080/09553000601002324

  303. 303.

    Thomasset N. Lochter A. Sympson C. J. Lund L. R. Williams D. R. Behrendtsen O. (1998 ). Expression of autoactivated stromelysin-1 in mammary glands of transgenic mice leads to a reactive stroma during early development. Am. J. Pathol. 153 457–467.

    Not in our library10.1016/s0002-9440(10)65589-7

  304. 304.

    Tong D. Liu Q. Wang L. A. Xie Q. Pang J. Huang Y. (2018 ). The roles of the COX2/PGE2/EP axis in therapeutic resistance. Cancer Metastasis Rev. 37 355–368.

    Not in our library10.1007/s10555-018-9752-y

  305. 305.

    Tran Q. Lee H. Park J. Kim S.-H. Park J. (2016 ). Targeting cancer metabolism-revisiting the Warburg effects. Toxicol. Res. 32 177–193.

    Not in our library10.5487/tr.2016.32.3.177

  306. 306.

    Trédan O. Galmarini C. M. Patel K. Tannock I. F. (2007 ). Drug resistance and the solid tumor microenvironment. J. Natl. Cancer Inst. 99 1441–1454.

    Not in our library10.1093/jnci/djm135

  307. 307.

    Truffi M. Sorrentino L. Corsi F. (2020 ). “Fibroblasts in the tumor microenvironment,” in Tumor Microenvironment: Non-Hematopoietic Cells, ed. Birbrair A. (Cham: Springer International Publishing), 15–29.

    Not in our library10.1007/978-3-030-37184-5_2

  308. 308.

    Tsai M. J. Chang W. A. Huang M. S. Kuo P. L. (2014 ). Tumor microenvironment: a new treatment target for cancer. ISRN Biochem. 2014:351959.

    Not in our library10.1155/2014/351959

  309. 309.
  310. 310.

    Umezawa K. Kojima I. Simizu S. Lin Y. Fukatsu H. Koide N. (2018 ). Therapeutic activity of plant-derived alkaloid conophylline on metabolic syndrome and neurodegenerative disease models. Hum. Cell 31 95–101.

    Not in our library10.1007/s13577-017-0196-4

  311. 311.

    Upagupta C. Shimbori C. Alsilmi R. Kolb M. (2018 ). Matrix abnormalities in pulmonary fibrosis. Eur. Respir Rev. 27:180033.

    Not in our library10.1183/16000617.0033-2018

  312. 312.

    Valencia A. M. Kadoch C. (2019 ). Chromatin regulatory mechanisms and therapeutic opportunities in cancer. Nat. Cell Biol. 21 152–161.

    Not in our library10.1038/s41556-018-0258-1

  313. 313.

    Vaquero J. Lobe C. Tahraoui S. Clapéron A. Mergey M. Merabtene F. (2018 ). The IGF2/IR/IGF1R pathway in tumor cells and myofibroblasts mediates resistance to egfr inhibition in cholangiocarcinoma. Clin. Cancer Res. 24 4282–4296.

    Not in our library10.1158/1078-0432.ccr-17-3725

  314. 314.

    Vaupel P. (2004 ). Tumor microenvironmental physiology and its implications for radiation oncology. Semin. Radiat. Oncol. 14 198–206.

    Not in our library10.1016/j.semradonc.2004.04.008

  315. 315.

    Vlachogiannis G. Hedayat S. Vatsiou A. Jamin Y. Fernández-Mateos J. Khan K. (2018 ). Patient-derived organoids model treatment response of metastatic gastrointestinal cancers. Science 359 920–926.

    Not in our library10.1126/science.aao2774

  316. 316.
  317. 317.

    Wang L. Zhang F. Cui J. Y. Chen L. Chen Y. T. Liu B. W. (2018 ). CAFs enhance paclitaxel resistance by inducing EMT through the IL-6/JAK2/STAT3 pathway. Oncol. Rep. 39 2081–2090.

    Not in our library10.3892/or.2018.6311

  318. 318.

    Wang X. Luo G. Zhang K. Cao J. Huang C. Jiang T. (2018 ). Hypoxic tumor-derived exosomal miR-301a mediates M2 macrophage polarization via PTEN/PI3Kγ to promote pancreatic cancer metastasis. Cancer Res. 78 4586–4598.

    Not in our library10.1158/0008-5472.can-17-3841

  319. 319.

    Wang M. Qiu R. Yu S. Xu X. Li G. Gu R. (2019 ). Paclitaxel-resistant gastric cancer MGC-803 cells promote epithelial-to-mesenchymal transition and chemoresistance in paclitaxel-sensitive cells via exosomal delivery of miR-155-5p. Int. J. Oncol. 54 326–338.

    Not in our library10.3892/ijo.2018.4601

  320. 320.

    Wang W. Kryczek I. Dostál L. Lin H. Tan L. Zhao L. (2016 ). Effector T Cells abrogate stroma-mediated chemoresistance in ovarian cancer. Cell 165 1092–1105.

    Not in our library10.1016/j.cell.2016.04.009

  321. 321.

    Wang W. L. Chang W. L. Yang H. B. Chang I. W. Lee C. T. Chang C. Y. (2015 ). Quantification of tumor infiltrating Foxp3+ regulatory T cells enables the identification of high-risk patients for developing synchronous cancers over upper aerodigestive tract. Oral. Oncol. 51 698–703.

    Not in our library10.1016/j.oraloncology.2015.04.015

  322. 322.

    Wang Y. Fang Z. Hong M. Yang D. Xie W. (2020 ). Long-noncoding RNAs (lncRNAs) in drug metabolism and disposition, implications in cancer chemo-resistance. Acta Pharmaceut. Sin. B 10 105–112.

    Not in our library10.1016/j.apsb.2019.09.011

  323. 323.

    Warfel N. A. El-Deiry W. S. (2014 ). HIF-1 signaling in drug resistance to chemotherapy. Curr. Med. Chem. 21 3021–3028.

    Not in our library10.2174/0929867321666140414101056

  324. 324.

    Watnick R. S. (2012 ). The role of the tumor microenvironment in regulating angiogenesis. Cold Spring Harbor Perspect. Med. 2:a006676.

    Not in our library10.1101/cshperspect.a006676

  325. 325.

    Wei S. C. Duffy C. R. Allison J. P. (2018 ). Fundamental mechanisms of immune checkpoint blockade therapy. Cancer Discov. 8 1069–1086.

    Not in our library10.1158/2159-8290.cd-18-0367

  326. 326.

    Weigelt B. Lo A. T. Park C. C. Gray J. W. Bissell M. J. (2010 ). HER2 signaling pathway activation and response of breast cancer cells to HER2-targeting agents is dependent strongly on the 3D microenvironment. Breast Cancer Res. Treatm. 122 35–43.

    Not in our library10.1007/s10549-009-0502-2

  327. 327.
  328. 328.

    Weis S. M. Cheresh D. A. (2011 ). Tumor angiogenesis: molecular pathways and therapeutic targets. Nat. Med. 17 1359–1370.

    Not in our library10.1038/nm.2537

  329. 329.
  330. 330.

    Wolchok J. D. Kluger H. Callahan M. K. Postow M. A. Rizvi N. A. Lesokhin A. M. (2013 ). Nivolumab plus ipilimumab in advanced melanoma. N. Engl. J. Med. 369 122–133.

    Not in our library10.1056/nejmoa1302369

  331. 331.

    Wu A. T. Srivastava P. Yadav V. K. Tzeng D. T. Iamsaard S. Su C.-Y. (2020 ). Ovatodiolide, isolated from Anisomeles indica, suppresses bladder carcinogenesis through suppression of mTOR/β-catenin/CDK6 and exosomal miR-21 derived from M2 tumor-associated macrophages. Toxicol. Appl. Pharmacol. 401:115109.

    Not in our library10.1016/j.taap.2020.115109

  332. 332.

    Wu D. Zhuo L. Wang X. (2017 ). Metabolic reprogramming of carcinoma-associated fibroblasts and its impact on metabolic heterogeneity of tumors. Semin. Cell Dev. Biol. 64 125–131.

    Not in our library10.1016/j.semcdb.2016.11.003

  333. 333.

    Wu J. Li G. Li L. Li D. Dong Z. Jiang P. (2021 ). Asparagine enhances LCK signalling to potentiate CD8+ T-cell activation and anti-tumour responses. Nat. Cell Biol. 23 75–86.

    Not in our library10.1038/s41556-020-00615-4

  334. 334.

    Xia Y. Jiang L. Zhong T. (2018 ). The role of HIF-1α in chemo-/radioresistant tumors. OncoTargets Ther. 11 3003–3011.

    Not in our library10.2147/ott.s158206

  335. 335.
  336. 336.

    Xu M. Liu M. Du X. Li S. Li H. Li X. (2015 ). Intratumoral delivery of IL-21 overcomes Anti-Her2/Neu resistance through shifting tumor-associated macrophages from M2 to M1 Phenotype. J. Immunol. 194 4997–5006.

    Not in our library10.4049/jimmunol.1402603

  337. 337.

    Yamada K. Maishi N. Akiyama K. Towfik Alam M. Ohga N. Kawamoto T. (2015 ). CXCL12–CXCR7 axis is important for tumor endothelial cell angiogenic property. Int. J. Cancer 137 2825–2836.

    Not in our library10.1002/ijc.29655

  338. 338.

    Yamashita M. Ogawa T. Zhang X. Hanamura N. Kashikura Y. Takamura M. (2012 ). Role of stromal myofibroblasts in invasive breast cancer: stromal expression of alpha-smooth muscle actin correlates with worse clinical outcome. Breast Cancer 19 170–176.

    Not in our library10.1007/s12282-010-0234-5

  339. 339.
  340. 340.

    Yang G. Shi R. Zhang Q. (2020 ). Hypoxia and oxygen-sensing signaling in gene regulation and cancer progression. Int. J. Mol. Sci. 21:8162.

    Not in our library10.3390/ijms21218162

  341. 341.

    Yang Y. Neo S. Y. Chen Z. Cui W. Chen Y. Guo M. (2020 ). Thioredoxin activity confers resistance against oxidative stress in tumor-infiltrating NK cells. J. Clin. Invest. 130 5508–5522.

    Not in our library10.1172/jci137585

  342. 342.

    Yang J. Lu Y. Lin Y. Y. Zheng Z. Y. Fang J. H. He S. (2016 ). Vascular mimicry formation is promoted by paracrine TGF-β and SDF1 of cancer-associated fibroblasts and inhibited by miR-101 in hepatocellular carcinoma. Cancer Lett. 383 18–27.

    Not in our library10.1016/j.canlet.2016.09.012

  343. 343.

    Yarnold J. Brotons M. C. (2010 ). Pathogenetic mechanisms in radiation fibrosis. Radiother. Oncol. 97 149–161.

    Not in our library10.1016/j.radonc.2010.09.002

  344. 344.

    Yin W. M. Li Y. W. Gu Y. Q. Luo M. (2020 ). Nanoengineered targeting strategy for cancer immunotherapy. Acta Pharmacol. Sin. 41 902–910.

    Not in our library10.1038/s41401-020-0417-3

  345. 345.

    Yin Y. Yao S. Hu Y. Feng Y. Li M. Bian Z. (2017 ). The immune-microenvironment confers chemoresistance of colorectal cancer through macrophage-derived IL6. Clin. Cancer Res. 23 7375–7387.

    Not in our library10.1158/1078-0432.ccr-17-1283

  346. 346.

    Yonenaga Y. Mori A. Onodera H. Yasuda S. Oe H. Fujimoto A. (2005 ). Absence of smooth muscle actin-positive pericyte coverage of tumor vessels correlates with hematogenous metastasis and prognosis of colorectal cancer patients. Oncology 69 159–166.

    Not in our library10.1159/000087840

  347. 347.

    Yoshizaki T. Kondo S. Wakisaka N. Murono S. Endo K. Sugimoto H. (2013 ). Pathogenic role of Epstein-Barr virus latent membrane protein-1 in the development of nasopharyngeal carcinoma. Cancer Lett. 337 1–7.

    Not in our library10.1016/j.canlet.2013.05.018

  348. 348.

    You Y. Shan Y. Chen J. Yue H. You B. Shi S. (2015 ). Matrix metalloproteinase 13-containing exosomes promote nasopharyngeal carcinoma metastasis. Cancer Sci. 106 1669–1677.

    Not in our library10.1111/cas.12818

  349. 349.
  350. 350.

    Yuan M.-M. Xu Y.-Y. Chen L. Li X.-Y. Qin J. Shen Y. (2015 ). TLR3 expression correlates with apoptosis, proliferation and angiogenesis in hepatocellular carcinoma and predicts prognosis. BMC Cancer 15:245.

    Not in our library10.1186/s12885-015-1262-5

  351. 351.

    Zaidi M. Fu F. Cojocari D. McKee T. D. Wouters B. G. (2019 ). Quantitative visualization of hypoxia and proliferation gradients within histological tissue sections. Front. Bioeng. Biotechnol. 7:397.

    Not in our library10.3389/fbioe.2019.00397

  352. 352.
  353. 353.
  354. 354.

    Zhang D. Li L. Jiang H. Li Q. Wang-Gillam A. Yu J. (2018 ). Tumor-stroma IL1β-IRAK4 feedforward circuitry drives tumor fibrosis, chemoresistance, and poor prognosis in pancreatic cancer. Cancer Res. 78 1700–1712.

    Not in our library10.1158/0008-5472.can-17-1366

  355. 355.

    Zhang H. Ozaki I. Mizuta T. Matsuhashi S. Yoshimura T. Hisatomi A. (2002 ). β1-integrin protects hepatoma cells from chemotherapy induced apoptosis via a mitogen-activated protein kinase dependent pathway. Cancer 95 896–906.

    Not in our library10.1002/cncr.10751

  356. 356.

    Zhang J. Pavlova N. N. Thompson C. B. (2017 ). Cancer cell metabolism: the essential role of the nonessential amino acid, glutamine. Embo J. 36 1302–1315.

    Not in our library10.15252/embj.201696151

  357. 357.

    Zhang Q. Bing Z. Tian J. Wang X. Liu R. Li Y. (2019 ). Integrating radiosensitive genes improves prediction of radiosensitivity or radioresistance in patients with oesophageal cancer. Oncol. Lett. 17 5377–5388.

    Not in our library10.3892/ol.2019.10240

  358. 358.

    Zhang Z. Yu X. Wang Z. Wu P. Huang J. (2015 ). Anthracyclines potentiate anti-tumor immunity: a new opportunity for chemoimmunotherapy. Cancer Lett. 369 331–335.

    Not in our library10.1016/j.canlet.2015.10.002

  359. 359.

    Zhao J. (2016 ). Cancer stem cells and chemoresistance: the smartest survives the raid. Pharmacol. Ther. 160 145–158.

    Not in our library10.1016/j.pharmthera.2016.02.008

  360. 360.

    Zhao J. Du F. Luo Y. Shen G. Zheng F. Xu B. (2015 ). The emerging role of hypoxia-inducible factor-2 involved in chemo/radioresistance in solid tumors. Cancer Treat. Rev. 41 623–633.

    Not in our library10.1016/j.ctrv.2015.05.004

  361. 361.
  362. 362.

    Zhao Q. Tan B. B. Li Y. Fan L. Q. Yang P. G. Tian Y. (2016 ). Enhancement of drug sensitivity by knockdown of HIF-1α in gastric carcinoma cells. Oncol. Res. 23 129–136.

    Not in our library10.3727/096504015x14500513118029

  363. 363.

    Zhen Z. Tang W. Wang M. Zhou S. Wang H. Wu Z. (2017 ). Protein nanocage mediated fibroblast-activation protein targeted photoimmunotherapy to enhance cytotoxic t cell infiltration and tumor control. Nano Lett. 17 862–869.

    Not in our library10.1021/acs.nanolett.6b04150

  364. 364.

    Zheng H. Zhao W. Yan C. Watson C. C. Massengill M. Xie M. (2016 ). HDAC inhibitors enhance T-Cell chemokine expression and augment response to PD-1 immunotherapy in lung adenocarcinoma. Clin. Cancer Res. 22 4119–4132.

    Not in our library10.1158/1078-0432.ccr-15-2584

  365. 365.
  366. 366.
  367. 367.

    Zhong Z. Virshup D. M. (2020 ). Wnt signaling and drug resistance in cancer. Mol. Pharmacol. 97 72–89.

    Not in our library10.1124/mol.119.117978

  368. 368.

    Zhou Z. Piao Y. Hao L. Wang G. Zhou Z. Shen Y. (2019 ). Acidity-responsive shell-sheddable camptothecin-based nanofibers for carrier-free cancer drug delivery. Nanoscale 11 15907–15916.

    Not in our library10.1039/c9nr03872h

  369. 369.

    Zingg D. Arenas-Ramirez N. Sahin D. Rosalia R. A. Antunes A. T. Haeusel J. (2017 ). The histone methyltransferase Ezh2 controls mechanisms of adaptive resistance to tumor immunotherapy. Cell Rep. 20 854–867.

    Not in our library10.1016/j.celrep.2017.07.007

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