scholarly journals HIF1-alpha expressing cells induce a hypoxic-like response in neighbouring cancer cells

2018 ◽  
Author(s):  
Hannah Harrison ◽  
Henry J Pegg ◽  
Jamie Thompson ◽  
Christian Bates ◽  
Paul Shore

AbstractHypoxia stimulates metastasis in cancer and is linked to poor patient prognosis. In tumours, oxygen levels vary and hypoxic regions exist within a generally well-oxygenated tumour. However, whilst the heterogeneous environment is known to contribute to metastatic progression, little is known about the mechanism by which heterogeneic hypoxia contributes to cancer progression. This is largely because existing experimental models do not recapitulate the heterogeneous nature of hypoxia. The primary effector of the hypoxic response is the transcription factor Hypoxia inducible factor 1-alpha (HIF1-alpha). HIF1-alpha is stabilised in response to low oxygen levels in the cellular environment and its expression is seen in hypoxic regions throughout the tumour.We have developed a model system in which HIF1-alpha can be induced within a sub-population of cancer cells, thus enabling us to mimic the effects of heterogeneic HIF1-alpha expression.We show that induction of HIF1-alpha not only recapitulates elements of the hypoxic response in the induced cells but also results in significant changes in proliferation, gene expression and mammosphere formation within the HIF1-alpha negative population.These findings suggest that the HIF1-alpha expressing cells found within hypoxic regions are likely to contribute to the subsequent progression of a tumour by modifying the behaviour of cells in the non-hypoxic regions of the local micro-environment.

2020 ◽  
Vol 245 (13) ◽  
pp. 1073-1086
Author(s):  
Sukanya Roy ◽  
Subhashree Kumaravel ◽  
Ankith Sharma ◽  
Camille L Duran ◽  
Kayla J Bayless ◽  
...  

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.


Physiology ◽  
2014 ◽  
Vol 29 (3) ◽  
pp. 168-176 ◽  
Author(s):  
Ataman Sendoel ◽  
Michael O. Hengartner

Eukaryotic life depends largely on molecular oxygen. During evolution, ingenious mechanisms have evolved that allow organisms to adapt when oxygen levels decrease. Many of these adaptional responses to low oxygen are orchestrated by the heterodimeric transcription factor hypoxia-inducible factor (HIF). Here, we review the link between HIF and apoptosis.


Oncogene ◽  
2019 ◽  
Vol 39 (7) ◽  
pp. 1543-1556 ◽  
Author(s):  
Ran Cheng ◽  
Sandrine Billet ◽  
Chuanxia Liu ◽  
Subhash Haldar ◽  
Diptiman Choudhury ◽  
...  

Abstract Periodontal diseases can lead to chronic inflammation affecting the integrity of the tooth supporting tissues. Recently, a striking association has been made between periodontal diseases and primary cancers in the absence of a mechanistic understanding. Here we address the effect of periodontal inflammation (PI) on tumor progression, metastasis, and possible underlining mechanisms. We show that an experimental model of PI in mice can promote lymph node (LN) micrometastasis, as well as head and neck metastasis of 4T1 breast cancer cells, both in early and late stages of cancer progression. The cervical LNs had a greater tumor burden and infiltration of MDSC and M2 macrophages compared with LNs at other sites. Pyroptosis and the resultant IL-1β production were detected in patients with PI, mirrored in mouse models. Anakinra, IL-1 receptor antagonist, limited metastasis, and MDSC recruitment at early stages of tumor progression, but failed to reverse established metastatic tumors. PI and the resulting production of IL-1β was found to promote CCL5, CXCL12, CCL2, and CXCL5 expression. These chemokines recruit MDSC and macrophages, finally enabling the generation of a premetastatic niche in the inflammatory site. These findings support the idea that periodontal inflammation promotes metastasis of breast cancer by recruiting MDSC in part by pyroptosis-induced IL-1β generation and downstream CCL2, CCL5, and CXCL5 signaling in the early steps of metastasis. These studies define the role for IL-1β in the metastatic progression of breast cancer and highlight the need to control PI, a pervasive inflammatory condition in older patients.


Cancers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 614 ◽  
Author(s):  
Gabriella D’Orazi ◽  
Mara Cirone

The capability of cancer cells to manage stress induced by hypoxia, nutrient shortage, acidosis, redox imbalance, loss of calcium homeostasis and exposure to drugs is a key factor to ensure cancer survival and chemoresistance. Among the protective mechanisms utilized by cancer cells to cope with stress a pivotal role is played by the activation of heat shock proteins (HSP) response, anti-oxidant response induced by nuclear factor erythroid 2-related factor 2 (NRF2), the hypoxia-inducible factor-1 (HIF-1), the unfolded protein response (UPR) and autophagy, cellular processes strictly interconnected. However, depending on the type, intensity or duration of cellular stress, the balance between pro-survival and pro-death pathways may change, and cell survival may be shifted into cell death. Mutations of p53 (mutp53), occurring in more than 50% of human cancers, may confer oncogenic gain-of-function (GOF) to the protein, mainly due to its stabilization and interaction with the above reported cellular pathways that help cancer cells to adapt to stress. This review will focus on the interplay of mutp53 with HSPs, NRF2, UPR, and autophagy and discuss how the manipulation of these interconnected processes may tip the balance towards cell death or survival, particularly in response to therapies.


2020 ◽  
Vol 21 (7) ◽  
pp. 2313 ◽  
Author(s):  
Giuseppina Roscigno ◽  
Assunta Cirella ◽  
Alessandra Affinito ◽  
Cristina Quintavalle ◽  
Iolanda Scognamiglio ◽  
...  

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.


2011 ◽  
Vol 286 (12) ◽  
pp. 10773-10782 ◽  
Author(s):  
Anna Grazia Recchia ◽  
Ernestina Marianna De Francesco ◽  
Adele Vivacqua ◽  
Diego Sisci ◽  
Maria Luisa Panno ◽  
...  

GPR30, also known as GPER, has been suggested to mediate rapid effects induced by estrogens in diverse normal and cancer tissues. Hypoxia is a common feature of solid tumors involved in apoptosis, cell survival, and proliferation. The response to low oxygen environment is mainly mediated by the hypoxia-inducible factor named HIF-1α, which activates signaling pathways leading to adaptive mechanisms in tumor cells. Here, we demonstrate that the hypoxia induces HIF-1α expression, which in turn mediates the up-regulation of GPER and its downstream target CTGF in estrogen receptor-negative SkBr3 breast cancer cells and in HL-1 cardiomyocytes. Moreover, we show that HIF-1α-responsive elements located within the promoter region of GPER are involved in hypoxia-dependent transcription of GPER, which requires the ROS-induced activation of EGFR/ERK signaling in both SkBr3 and HL-1 and cells. Interestingly, the apoptotic response to hypoxia was prevented by estrogens through GPER in SkBr3 cells. Taken together, our data suggest that the hypoxia-induced expression of GPER may be included among the mechanisms involved in the anti-apoptotic effects elicited by estrogens, particularly in a low oxygen microenvironment.


2016 ◽  
Vol 38 (1) ◽  
pp. 9-12 ◽  
Author(s):  
J Ajdukovic

Approximately 1.0–1.5% of the genome is transcriptionally regulated by hypoxia, and hypoxia-inducible factor (HIF)-1α is the transcription factor modulating many of these genes. Cancer cells are able to survive hypoxic environments and hypoxia itself can activate adaptive cellular responses that contribute to tumor progression. Many HIF-1α-mediated biological effects are beneficial for tumor progression, including metabolic shift toward glycolysis, inhibition of fatty acid β-oxidation, production of cellular reacreactive oxygen species and altering expression of tumor suppressor genes. HIF-1 promotes selective mitochondrial autophagy, resisand altering expression of tumor suppressor genes. HIF-1 promotes selective mitochondrial autophagy, resistance to T cell mediated lysis of cancer cells, induction of pluripotent cancer stem cells, epithelial-mesenchymal and epithelialmesenchymal-endothelial transitions beneficial for tumor growth and progression, loss of E-cadherin. HIF-1 also induces production of signal molecules and cytokines by carcinoma-associated fibroblasts and upregulation of certain microRNAs important for cancer progression. This minireview focuses on the HIF-1 promoting role in tumor initiation and progression and HIF-1 targeting. HIF-1 pathway downregulation seems to be promising in future cancer treatment.


2020 ◽  
Vol 10 (9) ◽  
pp. 3179-3188
Author(s):  
Tara Kelly ◽  
Hanne Johnsen ◽  
Erik Burgerhout ◽  
Helge Tveiten ◽  
Tina Thesslund ◽  
...  

Abstract Survival and growth of developing salmonids are negatively affected by low oxygen levels within gravel nests in natural streams, and hypoxic stress is often experienced by farmed Atlantic salmon (Salmo salar) within hatcheries. Exposure to hypoxia during early development may have long-lasting effects by altering epigenetic marks and gene expression in oxygen regulatory pathways. Here, we examine the transcriptomic response to low dissolved oxygen (DO) in post-hatch salmon reared continuously in 30%, 60% or 100% DO from fertilization until start of feeding. RNA sequencing revealed multiple differentially expressed genes, including oxygen transporting hemoglobin embryonic α subunit (hbae) and EGLN3 family hypoxia-inducible factor 3 (egln3) which regulates the stability of hypoxia inducible factor 1α (HIF-1α). Both hbae and egln3 displayed expression levels inversely correlated to oxygen concentration, and DNA methylation patterns within the egln3 promoter were negatively associated with the transcript levels. These results suggest that epigenetic processes are influenced by low oxygen levels during early development in Atlantic salmon to upregulate hypoxia-response genes.


2020 ◽  
Vol 21 (7) ◽  
pp. 642-654
Author(s):  
Anand Chopra ◽  
Hemanta Adhikary ◽  
William G. Willmore ◽  
Kyle K. Biggar

Cellular responses to hypoxia (low oxygen) are governed by oxygen sensitive signaling pathways. Such pathways, in part, are controlled by enzymes with oxygen-dependent catalytic activity, of which the role of prolyl 4-hydroxylases has been widely reviewed. These enzymes inhibit hypoxic response by inducing the oxygen-dependent degradation of hypoxia-inducible factor 1α, the master regulator of the transcriptional hypoxic response. Jumonji C domain-containing lysine demethylases are similar enzymes which share the same oxygen-dependent catalytic mechanism as prolyl 4- hydroxylases. Traditionally, the role of lysine demethylases has been studied in relation to demethylation activity against histone substrates, however, within the past decade an increasing number of nonhistone protein targets have been revealed, some of which have a key role in survival in the hypoxic tumor microenvironment. Within this review, we highlight the involvement of methyllysine in the hypoxic response with a focus on the HIF signaling pathway, the regulation of demethylase activity by oxygen, and provide insights into notable areas of future hypoxic demethylase research.


2012 ◽  
Vol 303 (10) ◽  
pp. G1164-G1173 ◽  
Author(s):  
Martin Haugen ◽  
Rikard Dammen ◽  
Bernhard Svejda ◽  
Bjorn I. Gustafsson ◽  
Roswitha Pfragner ◽  
...  

The chemomechanosensory function of the gut enterochromaffin (EC) cell enables it to respond to dietary agents and mechanical stretch. We hypothesized that the EC cell, which also sensed alterations in luminal or mucosal oxygen level, was physiologically sensitive to fluctuations in O2. Given that low oxygen levels induce 5-HT production and secretion through a hypoxia inducible factor 1α (HIF-1α)-dependent pathway, we also hypothesized that increasing O2would reduce 5-HT production and secretion. Isolated normal EC cells as well as the well-characterized EC cell model KRJ-I were used to examine HIF signaling (luciferase-assays), hypoxia transcriptional response element (HRE)-mediated transcription (PCR), signaling pathways (Western blot), and 5-HT release (ELISA) during exposure to different oxygen levels. Normal EC cells and KRJ-I cells express HIF-1α, and transient transfection with Renilla luciferase under HRE control identified a hypoxia-mediated pathway in these cells. PCR confirmed activation of HIF-downstream targets, GLUT1, IGF2, and VEGF under reduced O2levels (0.5%). Reducing O2also elevated 5-HT secretion (2–3.2-fold) as well as protein levels of HIF-1α (1.7–3-fold). Increasing O2to 100% inhibited HRE-mediated signaling, transcription, reduced 5-HT secretion, and significantly lowered HIF-1α levels (∼75% of control). NF-κB signaling was also elevated during hypoxia (1.2–1.6-fold), but no significant changes were noted in PKA/cAMP. We concluded that gut EC cells are oxygen responsive, and alterations in O2levels differentially activate HIF-1α and tryptophan hydroxylase 1, as well as NF-κB signaling. This results in alterations in 5-HT production and secretion and identifies that the chemomechanosensory role of EC cells extends to oxygen sensing.


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