scholarly journals Bridging angiogenesis and immune evasion in the hypoxic tumor microenvironment

2018 ◽  
Vol 315 (6) ◽  
pp. R1072-R1084 ◽  
Author(s):  
Luana Schito
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Tumor Vasculature ◽  
Antiangiogenic Agents ◽  
Pathophysiological Mechanism ◽  
Feedforward Loop ◽  
Antiangiogenic Therapies ◽  
Solid Malignancies ◽  
Hypoxic Tumor

Hypoxia (low O2) is a ubiquitous microenvironmental factor promoting cancer progression, metastasis, and mortality, owing to the ability of cancer cells to co-opt physiological angiogenic responses. Notwithstanding, the pathophysiological induction of angiogenesis results in an abnormal tumor vasculature, further aggravating hypoxia in a feedforward loop that limits the efficacy of molecular targeted therapies. Recent studies suggest that, besides their canonical roles, angiogenic factors promote a panoply of immunosuppressive effects in the tumor microenvironment. Therefore, intratumoral hypoxia emerges as a hitherto unrecognized mechanism evolutionarily repurposing angiogenic molecules as (patho)physiological immunomodulators. On the other hand, antiangiogenic therapies could be aimed at impeding both tumor growth and immunotolerance toward cancer cells, a beneficial effect that can be countered if hypoxia signaling pathways are left unchecked, leading to therapeutic failure. This review summarizes evidence supporting the hypothesis that hypoxia acts as a common pathophysiological mechanism of resistance to immunotherapeutic and antiangiogenic agents while proposing potential strategies to curtail resistance and mortality in patients bearing solid malignancies.

scholarly journals Hypoxic tumor microenvironment: Implications for cancer therapy

2020 ◽  
Vol 245 (13) ◽  
pp. 1073-1086
Author(s):  
Sukanya Roy ◽  
Subhashree Kumaravel ◽  
Ankith Sharma ◽  
Camille L Duran ◽  
Kayla J Bayless ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Metabolic Regulation ◽  
Molecular Mechanisms ◽  
Hypoxia Inducible Factor ◽  
Tumor Vasculature ◽  
Therapeutic Strategies ◽  
Therapeutic Resistance ◽  
Low Oxygen ◽  
Cancer Types

Hypoxia or low oxygen concentration in tumor microenvironment has widespread effects ranging from altered angiogenesis and lymphangiogenesis, tumor metabolism, growth, and therapeutic resistance in different cancer types. A large number of these effects are mediated by the transcription factor hypoxia inducible factor 1⍺ (HIF-1⍺) which is activated by hypoxia. HIF1⍺ induces glycolytic genes and reduces mitochondrial respiration rate in hypoxic tumoral regions through modulation of various cells in tumor microenvironment like cancer-associated fibroblasts. Immune evasion driven by HIF-1⍺ further contributes to enhanced survival of cancer cells. By altering drug target expression, metabolic regulation, and oxygen consumption, hypoxia leads to enhanced growth and survival of cancer cells. Tumor cells in hypoxic conditions thus attain aggressive phenotypes and become resistant to chemo- and radio- therapies resulting in higher mortality. While a number of new therapeutic strategies have succeeded in targeting hypoxia, a significant improvement of these needs a more detailed understanding of the various effects and molecular mechanisms regulated by hypoxia and its effects on modulation of the tumor vasculature. This review focuses on the chief hypoxia-driven molecular mechanisms and their impact on therapeutic resistance in tumors that drive an aggressive phenotype. Impact statement Hypoxia contributes to tumor aggressiveness and promotes growth of many solid tumors that are often resistant to conventional therapies. In order to achieve successful therapeutic strategies targeting different cancer types, it is necessary to understand the molecular mechanisms and signaling pathways that are induced by hypoxia. Aberrant tumor vasculature and alterations in cellular metabolism and drug resistance due to hypoxia further confound this problem. This review focuses on the implications of hypoxia in an inflammatory TME and its impact on the signaling and metabolic pathways regulating growth and progression of cancer, along with changes in lymphangiogenic and angiogenic mechanisms. Finally, the overarching role of hypoxia in mediating therapeutic resistance in cancers is discussed.

scholarly journals Metabolic Alterations in Pancreatic Cancer Progression

Cancers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 2 ◽  
Author(s):  
Enza Vernucci ◽  
Jaime Abrego ◽  
Venugopal Gunda ◽  
Surendra K. Shukla ◽  
Aneesha Dasgupta ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Precancerous Lesions ◽  
Genetically Engineered ◽  
Metabolic Reprogramming ◽  
Pancreatic Tumors ◽  
Metabolic Alterations ◽  
Genetically Engineered Mice

Pancreatic cancer is the third leading cause of cancer-related deaths in the USA. Pancreatic tumors are characterized by enhanced glycolytic metabolism promoted by a hypoxic tumor microenvironment and a resultant acidic milieu. The metabolic reprogramming allows cancer cells to survive hostile microenvironments. Through the analysis of the principal metabolic pathways, we identified the specific metabolites that are altered during pancreatic cancer progression in the spontaneous progression (KPC) mouse model. Genetically engineered mice exhibited metabolic alterations during PanINs formation, even before the tumor development. To account for other cells in the tumor microenvironment and to focus on metabolic adaptations concerning tumorigenic cells only, we compared the metabolic profile of KPC and orthotopic tumors with those obtained from KPC-tumor derived cell lines. We observed significant upregulation of glycolysis and the pentose phosphate pathway metabolites even at the early stages of pathogenesis. Other biosynthetic pathways also demonstrated a few common perturbations. While some of the metabolic changes in tumor cells are not detectable in orthotopic and spontaneous tumors, a significant number of tumor cell-intrinsic metabolic alterations are readily detectable in the animal models. Overall, we identified that metabolic alterations in precancerous lesions are maintained during cancer development and are largely mirrored by cancer cells in culture conditions.

scholarly journals miR-216a Acts as a Negative Regulator of Breast Cancer by Modulating Stemness Properties and Tumor Microenvironment

2020 ◽  
Vol 21 (7) ◽  
pp. 2313 ◽  
Author(s):  
Giuseppina Roscigno ◽  
Assunta Cirella ◽  
Alessandra Affinito ◽  
Cristina Quintavalle ◽  
Iolanda Scognamiglio ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Stem Cells ◽  
Tumor Microenvironment ◽  
Cancer Stem Cells ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Negative Regulator ◽  
Mammosphere Formation ◽  
Incidence And Mortality ◽  
Cells Of The Microenvironment

Breast cancer is the most frequent malignancy in females in terms of both incidence and mortality. Underlying the high mortality rate is the presence of cancer stem cells, which divide indefinitely and are resistant to conventional chemotherapies, so causing tumor relapse. In the present study, we identify miR-216a-5p as a downregulated microRNA in breast cancer stem cells vs. the differentiated counterpart. We demonstrate that overexpression of miR-216a-5p impairs stemness markers, mammosphere formation, ALDH activity, and the level of Toll-like receptor 4 (TLR4), which plays a significant role in breast cancer progression and metastasis by leading to the release of pro-inflammatory molecules, such as interleukin 6 (IL-6). Indeed, miR-216a regulates the crosstalk between cancer cells and the cells of the microenvironment, in particular cancer-associated fibroblasts (CAFs), through regulation of the TLR4/IL6 pathway. Thus, miR-216a has an important role in the regulation of stem phenotype, decreasing stem-like properties and affecting the cross-talk between cancer cells and the tumor microenvironment.

scholarly journals Aneuploid Circulating Tumor-Derived Endothelial Cell (CTEC): A Novel Versatile Player in Tumor Neovascularization and Cancer Metastasis

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1539 ◽  
Author(s):  
Peter Ping Lin
Keyword(s):  
Endothelial Cells ◽  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Cancer Metastasis ◽  
Epithelial To Mesenchymal Transition ◽  
Vasculogenic Mimicry ◽  
Mesenchymal Transition ◽  
Tumor Neovascularization ◽  
Hypoxic Tumor

Hematogenous and lymphogenous cancer metastases are significantly impacted by tumor neovascularization, which predominantly consists of blood vessel-relevant angiogenesis, vasculogenesis, vasculogenic mimicry, and lymphatic vessel-related lymphangiogenesis. Among the endothelial cells that make up the lining of tumor vasculature, a majority of them are tumor-derived endothelial cells (TECs), exhibiting cytogenetic abnormalities of aneuploid chromosomes. Aneuploid TECs are generated from “cancerization of stromal endothelial cells” and “endothelialization of carcinoma cells” in the hypoxic tumor microenvironment. Both processes crucially engage the hypoxia-triggered epithelial-to-mesenchymal transition (EMT) and endothelial-to-mesenchymal transition (EndoMT). Compared to the cancerization process, endothelialization of cancer cells, which comprises the fusion of tumor cells with endothelial cells and transdifferentiation of cancer cells into TECs, is the dominant pathway. Tumor-derived endothelial cells, possessing the dual properties of cancerous malignancy and endothelial vascularization ability, are thus the endothelialized cancer cells. Circulating tumor-derived endothelial cells (CTECs) are TECs shed into the peripheral circulation. Aneuploid CD31+ CTECs, together with their counterpart CD31- circulating tumor cells (CTCs), constitute a unique pair of cellular circulating tumor biomarkers. This review discusses a proposed cascaded framework that focuses on the origins of TECs and CTECs in the hypoxic tumor microenvironment and their clinical implications for tumorigenesis, neovascularization, disease progression, and cancer metastasis. Aneuploid CTECs, harboring hybridized properties of malignancy, vascularization and motility, may serve as a unique target for developing a novel metastasis blockade cancer therapy.

scholarly journals Cytokine Secretions in Partial Breast Tumor Microenvironment With and Without Sulforaphane

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 274-274
Author(s):  
Courtney Merrick ◽  
Lauren Housley
Keyword(s):  
Breast Cancer ◽  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Treatment Options ◽  
Graduate Studies ◽  
Gm Csf ◽  
Funding Sources ◽  
Cytokine Levels ◽  
Vital Cell

Abstract Objectives Triple-negative breast cancer (TNBC) comprises 10–20% of breast cancer cases. It is particularly aggressive with limited and deleterious treatment options. Increasingly, research confirms that communication between cancer cells and neighboring macrophages promotes disease progression in part by secretion of cytokines that increase tumor cell proliferation, invasion, and metastasis. Sulforaphane (SFN) is a chemopreventive phytochemical found in cruciferous vegetables (broccoli) shown to alter cytokine secretion in macrophages and breast cancer cells grown in single culture. However, its effect in the tumor microenvironment remains unclear. This study aims to characterize cytokine profiles in media where TNBC cells and macrophages are grown in coculture with and without SFN treatment. We expect SFN to modify cytokine secretions in coculture media, suggesting SFN may disrupt vital cell-cell signaling needed for cancer progression. Methods TNBC cells (MDA-MB-231) were grown in Transwell plates with and without macrophages (THP-1 cells differentiated with PMA). Cell cultures (n = 3) were treated with either 15 μM SFN, DMSO (vehicle-control), or a non-treatment control. Cytokine levels were evaluated in media at 24 and 48 hours after treatment using BioPlex 2000 assay. Results Treatment with sulforaphane significantly reduced the levels of several targets in coculture including IL-1ra, IL-4, IL-5, IL-10, IL-12, IL-13, IL-15, IL-17, CCL2 (MCP-1), CCL11, CCL22, CCL26, CXCL12, IFN-y, G-CSF, GM-CSF, Eotaxin, and VEGF. Conversely, MIF was elevated following treatment. Effects were discovered at 24-hour and 48-hour time points. Conclusions We demonstrated that SFN altered the levels of numerous cellular signaling proteins in cancer cell-macrophage coculture, many of which are known to be involved with breast cancer progression. These results reveal mechanistic links underlying SFNs chemopreventive function and bolster SFNs potential as a treatment strategy for TNBC. Funding Sources Department of Nutrition and Food Science, CSU Chico; Graduate Studies, CSU Chico; CSUPERB: CSU Program for Education and Research in Biotechnology.

scholarly journals A role for the autophagic receptor, SQSTM1/p62, in trafficking NF-κB/RelA to nucleolar aggresomes

2020 ◽  
Author(s):  
Ian T Lobb ◽  
Pierre Morin ◽  
Kirsty Martin ◽  
Xhordi Lieshi ◽  
Karl Olsen ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Cancer Progression ◽  
Dominant Negative ◽  
Regulatory Proteins ◽  
Dominant Negative Mutant ◽  
Contributory Factor ◽  
Hallmarks Of Cancer ◽  
Solid Malignancies ◽  
Elevated Activity ◽  
Related Proteins

AbstractElevated NF-κB activity is a contributory factor in many haematological and solid malignancies. Nucleolar sequestration of NF-κB/RelA represses this elevated activity and mediates apoptosis of cancer cells. Here we set out to understand the mechanisms that control the nuclear/nucleolar distribution of RelA and other regulatory proteins, so that agents can be developed that specifically target these proteins to the organelle. We demonstrate that RelA accumulates in intra-nucleolar aggresomes in response to specific stresses. We also demonstrate that the autophagy receptor, SQSTM1/p62, accumulates alongside RelA in these nucleolar aggresomes. This accumulation is not a consequence of inhibited autophagy. Indeed, our data suggest nucleolar and autophagosomal accumulation of p62 are in active competition. We identify a conserved motif at the N-terminus of p62 that is essential for nucleoplasmic-to nucleolar transport of the protein. Furthermore, using a dominant negative mutant deleted for this nucleolar localisation signal (NoLS), we demonstrate a role for p62 in trafficking RelA and other aggresome-related proteins to nucleoli. Together, these data identify a novel role for p62 in trafficking nuclear proteins to nucleolar aggresomes under conditions of cell stress, thus maintaining nuclear proteostasis. They also provide invaluable information on the mechanisms that regulate the nuclear/nucleolar distribution of RelA that could be exploited for therapeutic purpose.SignificanceAberrant NF-κB activity drives many of the hallmarks of cancer and plays a key role in cancer progression. Nucleolar sequestration of NF-κB/RelA is one mechanism that switches off this activity and induces the death of cancer cells. Here we define a novel role for the autophagy receptor, SQSTM1/p62 in transport of nucleoplasmic NF-κB/RelA to nucleoli. Identification of this new trafficking mechanism opens up avenues for the development of a unique class of therapeutic agents that transport RelA and other cancer regulatory proteins to this organelle.

scholarly journals Nerves in the Tumor Microenvironment: Origin and Effects

2020 ◽  
Vol 8 ◽  
Author(s):  
Wenjun Wang ◽  
Lingyu Li ◽  
Naifei Chen ◽  
Chao Niu ◽  
Zhi Li ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Perineural Invasion ◽  
Vital Role ◽  
Cancer Growth ◽  
Alternative Route ◽  
Sympathetic Nervous ◽  
Molecular Bases

Studies have reported the vital role of nerves in tumorigenesis and cancer progression. Nerves infiltrate the tumor microenvironment thereby enhancing cancer growth and metastasis. Perineural invasion, a process by which cancer cells invade the surrounding nerves, provides an alternative route for metastasis and generation of tumor-related pain. Moreover, central and sympathetic nervous system dysfunctions and psychological stress-induced hormone network disorders may influence the malignant progression of cancer through multiple mechanisms. This reciprocal interaction between nerves and cancer cells provides novel insights into the cellular and molecular bases of tumorigenesis. In addition, they point to the potential utility of anti-neurogenic therapies. This review describes the evolving cross-talk between nerves and cancer cells, thus uncovers potential therapeutic targets for cancer.

scholarly journals Emerging Autophagy Functions Shape the Tumor Microenvironment and Play a Role in Cancer Progression - Implications for Cancer Therapy

2020 ◽  
Vol 10 ◽  
Author(s):  
Silvina Odete Bustos ◽  
Fernanda Antunes ◽  
Maria Cristina Rangel ◽  
Roger Chammas
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Therapy ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Stress Responses ◽  
Epithelial Mesenchymal Transition ◽  
Metastatic Potential ◽  
Secretory Proteins ◽  
Mesenchymal Transition ◽  
Independent Functions

The tumor microenvironment (TME) is a complex environment where cancer cells reside and interact with different types of cells, secreted factors, and the extracellular matrix. Additionally, TME is shaped by several processes, such as autophagy. Autophagy has emerged as a conserved intracellular degradation pathway for clearance of damaged organelles or aberrant proteins. With its central role, autophagy maintains the cellular homeostasis and orchestrates stress responses, playing opposite roles in tumorigenesis. During tumor development, autophagy also mediates autophagy-independent functions associated with several hallmarks of cancer, and therefore exerting several effects on tumor suppression and/or tumor promotion mechanisms. Beyond the concept of degradation, new different forms of autophagy have been described as modulators of cancer progression, such as secretory autophagy enabling intercellular communication in the TME by cargo release. In this context, the synthesis of senescence-associated secretory proteins by autophagy lead to a senescent phenotype. Besides disturbing tumor treatment responses, autophagy also participates in innate and adaptive immune signaling. Furthermore, recent studies have indicated intricate crosstalk between autophagy and the epithelial-mesenchymal transition (EMT), by which cancer cells obtain an invasive phenotype and metastatic potential. Thus, autophagy in the cancer context is far broader and complex than just a cell energy sensing mechanism. In this scenario, we will discuss the key roles of autophagy in the TME and surrounding cells, contributing to cancer development and progression/EMT. Finally, the potential intervention in autophagy processes as a strategy for cancer therapy will be addressed.

P16.09 Regulation of chromatin accessibility in the hypoxic tumor microenvironment of glioblastoma

2021 ◽  
Vol 23 (Supplement_2) ◽  
pp. ii57-ii57
Author(s):  
M Dzwigonska ◽  
J Mieczkowski ◽  
P Pilanc ◽  
S Cyranowski ◽  
A Kominek ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Single Cell ◽  
Cancer Cells ◽  
Single Cells ◽  
Therapy Resistance ◽  
Chromatin Accessibility ◽  
Open Chromatin ◽  
Dependent Manner ◽  
Protein Markers ◽  
Hypoxic Tumor

Abstract BACKGROUND Chromatin structure is often dysregulated in cancers, including glioblastoma (GBM), the most aggressive type of primary brain tumor. GBM has the poorest prognosis with no efficient cure to date due to diffusive growth into the brain, resistance to treatments and the immunosuppressive tumor microenvironment (TME). The growth and invasiveness of GBM is supported by the heterogeneous TME including local microglia and bone-marrow-derived macrophages (collectively known as glioma-associated microglia and macrophages, GAMs). In addition, tumor hypoxia is a key factor in the progression of GBM, as it can globally and rapidly alter gene expression, induce cancer cell invasiveness, stemness and lead to therapy resistance. Hypoxia can influence the pro-tumorigenic function of GAMs by inducing the expression of cytokines and cell surface receptors. However, little is known on the hypoxia-imposed chromatin changes of GAMs and GBM cells, which can in turn impact the interaction between these cell populations. Here we analyze these changes using a single-cell method, which preserves in situ hypoxia within the TME of GBM. MATERIAL AND METHODS Single-cell Pi-ATAC-seq (Protein-indexed Assay of Transposase Accessible Chromatin with sequencing) method in a GL261 murine glioma model was used to simultaneously assess genome-wide chromatin accessibility and expression of intracellular protein markers in single cells, enabling accurate selection of hypoxic and non-hypoxic tumor cells and GAMs. Pi-ATAC-seq is used on paraformaldehyde-perfused tumors and therefore allows capturing unaltered hypoxia-dependent cellular states, that often become distorted during dissociation and preparation of fresh material in most common single-cell methods. RESULTS We optimized Pi-ATAC method in a GL261 GBM mouse model, with specific sorting of GAMs using CD11b+ immunosorting followed by separation of microglia and macrophages, based on intensity of CD45 staining. HIF-1α induction and binding of pimonidazole were used to mark hypoxic populations. Currently, we are investigating the chromatin accessibility profiles of cancer cells and GAMs within the hypoxic tumor microenvironment of GBM. Exploring open chromatin profiles in GAMs and glioma-microglia co-cultures will allow to unravel the mechanisms of chromatin accessibility modulation in the oxygen-dependent manner. CONCLUSION In summary, we optimized the Pi-ATAC method in a mouse GBM model to characterize the chromatin openness changes in GAMs and cancer cells in response to hypoxic stress. Further validation of these results will provide the potential to identify novel markers for GAMs/glioma interactions in hypoxic GBMs and develop novel therapeutic targets.

Directing hypoxic tumor microenvironment and HIF to illuminate cancer immunotherapy's existing prospects and challenges in drug targets

2022 ◽  
Vol 23 ◽  
Author(s):  
Suman Kumar Ray ◽  
Sukhes Mukherjee
Keyword(s):  
Immune System ◽  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Drug Targets ◽  
Therapeutic Potential ◽  
Checkpoint Inhibitors ◽  
Cancer Drug ◽  
Cancer Therapies ◽  
Cellular Expression ◽  
Hypoxic Tumor

Abstract: Cancer is now also reflected as a disease of the tumor microenvironment, primarily supposed to be a decontrolled genetic and cellular expression disease. Over the past two decades, significant and rapid progress has been made in recognizing the dynamics of the tumor's microenvironment and its contribution to influencing the response to various anti-cancer therapies and drugs. Modulations in the tumor microenvironment and immune checkpoint blockade are interesting in cancer immunotherapy and drug targets. Simultaneously, the immunotherapeutic strategy can be done by modulating the immune regulatory pathway; however, the tumor microenvironment plays an essential role in suppressing the antitumor's immunity by its substantial heterogeneity. Hypoxia inducible factor (HIF) is a significant contributor to solid tumor heterogeneity and a key stressor in the tumor microenvironment to drive adaptations to prevent immune surveillance. Checkpoint inhibitors here halt the ability of cancer cells to stop the immune system from activating, and in turn, amplify your body's immune system to help destroy cancer cells. Common checkpoints that these inhibitors affect are the PD-1/PD-L1 and CTLA-4 pathways and important drugs involved are Ipilimumab and Nivolumab, mainly along with other drugs in this group. Targeting the hypoxic tumor microenvironment may provide a novel immunotherapy strategy, break down traditional cancer therapy resistance, and build the framework for personalized precision medicine and cancer drug targets. We hope that this knowledge can provide insight into the therapeutic potential of targeting Hypoxia and help to develop novel combination approaches of cancer drugs to increase the effectiveness of existing cancer therapies, including immunotherapy.

Sign in / Sign up

Export Citation Format

Share Document