Similar Datasets
Project description:Hypoxia Inducible Factor 1 Confers Androgen Independence in Prostate Cancer
| PRJNA472393 | ENA
Project description:This SuperSeries is composed of the SubSeries listed below.
2019-11-21 | GSE128884 | GEO
Project description:Enzalutamide is a potent second-generation androgen receptor (AR) antagonist with activity in metastatic castrate-resistant prostate cancer (CRPC). Although enzalutamide is initially effective, disease progression inevitably ensues with the emergence of resistance. Intratumoral hypoxia is also associated with CRPC progression and treatment resistance. Given that both AR and hypoxia inducible factor-1 α (HIF-1α) are key regulators of these processes, dual targeting of both signaling axes represents an attractive therapeutic approach. Crosstalk of the AR and HIF-1α signaling pathways were examined in prostate cancer cell lines (LNCaP, 22Rv1) with assays measuring the effect of androgen and hypoxia on AR-dependent and hypoxia-inducible gene transcription, protein expression, cell proliferation, and apoptosis. HIF-1α inhibition was achieved by siRNA silencing HIF-1α or via chetomin, a disruptor of HIF-1α-p300 interactions. In prostate cancer cells, the gene expression of AR targets (KLK3, FKBP5, TMPRSS2) was repressed by HIF-signaling; conversely, specific HIF-1α target expression was induced by dihydrotestosterone-mediated AR signaling. Treatment of CRPC cells with enzalutamide or HIF-1α inhibition attenuated AR-regulated and HIF-1α-mediated gene transcription. The combination of enzalutamide and HIF-1α inhibition was more effective than either treatment alone. Similarly, the combination also reduced vascular endothelial growth factor protein levels. HIF-1α siRNA synergistically enhanced the inhibitory effect of enzalutamide on cell growth in LNCaP and enzalutamide-resistant 22Rv1 cells via increased enzalutamide-induced apoptosis. In conclusion, the combination of enzalutamide with HIF-1α inhibition resulted in synergistic inhibition of AR-dependent and gene-specific HIF-dependent expression and prostate cancer cell growth.
| S-EPMC4429716 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2022-06-27 | GSE197781 | GEO
Project description:Hypoxia inducible factor 1 (HIF1) has been shown to cooperate with the androgen receptor (AR) in activation of oncogenic pathways in prostate cancer (PCa). Here we hypothesized that HIF1 also plays a role in PCa response to androgen deprivation therapy (ADT). Comparison of gene expression profiles of androgen exposed (AE) and androgen deprived (AD) CWR22 PCa xenografts identified 596 upregulated and 748 downregulated genes after ADT. Gene ontology (GO) analysis of the differentially expressed genes showed significant enrichment of the biological processes cell proliferation, cell cycle and metabolism and suggested suppression of these processes after ADT. A set of 80 hypoxia-inducible genes were identified in 22Rv1 and LNCaP cell lines treated with hypoxia and showed considerable overlap (53%) with the downregulated genes. Immunostaining of the hypoxia marker pimonidazole showed no difference between AE- and AD-tumors. Comparison of the differentially expressed genes with lists of 1115 direct AR- and 276 direct HIF1-target genes identified 138 AR- and 40 HIF1-targets that were regulated after ADT, including six shared AR- and HIF1-targets for which downregulation was confirmed with RT-PCR. Most HIF1-targets were downregulated and included in the significant biological processes and the set of hypoxia-inducible genes. The downregulation of HIF1-targets was consistent with decreased HIF1A immunostaining in AD- compared to AE-tumors (p=0.002). A decrease in HIF1A immunostaining after ADT was also demonstrated in a cohort of 35 PCa patients (p<0.001). These data suggest suppressed HIF1-signaling after ADT and a shared role of HIF1 and AR in the regressive phase of PCa after ADT.
2013-10-02 | GSE42868 | GEO
Project description:Hypoxia inducible factor 1 (HIF1) has been shown to cooperate with the androgen receptor (AR) in activation of oncogenic pathways in prostate cancer (PCa). Here we hypothesized that HIF1 also plays a role in PCa response to androgen deprivation therapy (ADT). Comparison of gene expression profiles of androgen exposed (AE) and androgen deprived (AD) CWR22 PCa xenografts identified 596 upregulated and 748 downregulated genes after ADT. Gene ontology (GO) analysis of the differentially expressed genes showed significant enrichment of the biological processes cell proliferation, cell cycle and metabolism and suggested suppression of these processes after ADT. A set of 80 hypoxia-inducible genes were identified in 22Rv1 and LNCaP cell lines treated with hypoxia and showed considerable overlap (53%) with the downregulated genes. Immunostaining of the hypoxia marker pimonidazole showed no difference between AE- and AD-tumors. Comparison of the differentially expressed genes with lists of 1115 direct AR- and 276 direct HIF1-target genes identified 138 AR- and 40 HIF1-targets that were regulated after ADT, including six shared AR- and HIF1-targets for which downregulation was confirmed with RT-PCR. Most HIF1-targets were downregulated and included in the significant biological processes and the set of hypoxia-inducible genes. The downregulation of HIF1-targets was consistent with decreased HIF1A immunostaining in AD- compared to AE-tumors (p=0.002). A decrease in HIF1A immunostaining after ADT was also demonstrated in a cohort of 35 PCa patients (p<0.001). These data suggest suppressed HIF1-signaling after ADT and a shared role of HIF1 and AR in the regressive phase of PCa after ADT. Prostate cancer xenografts were subjected to adrogen deprivation therapy and analysed with regard to changes in gene expressions. Cell culture experiments were performed to generate prostate cancer specific gene lists associated with hypoxia.
2013-10-02 | E-GEOD-42868 | biostudies-arrayexpress
Project description:BACKGROUND:Therapeutic targeting of the androgen signaling pathway is a mainstay treatment for prostate cancer. Although initially effective, resistance to androgen targeted therapies develops followed by disease progression to castrate-resistant prostate cancer (CRPC). Hypoxia and HIF1a have been implicated in the development of resistance to androgen targeted therapies and progression to CRCP. The interplay between the androgen and hypoxia/HIF1a signaling axes was investigated. METHODS:In vitro stable expression of HIF1a was established in the LNCaP cell line by physiological induction or retroviral transduction. Tumor xenografts with stable expression of HIF1a were established in castrated and non-castrated mouse models. Gene expression analysis identified transcriptional changes in response to androgen treatment, hypoxia and HIF1a. The binding sites of the AR and HIF transcription factors were identified using ChIP-seq. RESULTS:Androgen and HIF1a signaling promoted proliferation in vitro and enhanced tumor growth in vivo. The stable expression of HIF1a in vivo restored tumor growth in the absence of endogenous androgens. Hypoxia reduced AR binding sites whereas HIF binding sites were increased with androgen treatment under hypoxia. Gene expression analysis identified seven genes that were upregulated both by AR and HIF1a, of which six were prognostic. CONCLUSIONS:The oncogenic AR, hypoxia and HIF1a pathways support prostate cancer development through independent signaling pathways and transcriptomic profiles. AR and hypoxia/HIF1a signaling pathways independently promote prostate cancer progression and therapeutic targeting of both pathways simultaneously is warranted.
| S-EPMC7249645 | biostudies-literature
Project description:Through regulating the expression of hundreds of genes, hypoxia-inducible factor -1(HIF-1) plays a critical role in hypoxic adaption of cancer cells and is considered as a target for cancer therapy. Here we show that montelukast, a clinical leukotriene receptor antagonist for the treatment of asthma, inhibits hypoxia or CoCl2-induced HIF-1α activation and reduces its protein expression in prostate cancer cells. However, the other two leukotriene receptor antagonists, pranlukast and zafirlukast, cannot decrease HIF-1α protein, which indicates that montelukast-induced downregulation of HIF-1α is not mediated by leukotriene receptor. Neither proteasome inhibitor MG132 nor the lysosomal inhibitor chloroquine (CQ) can block montelukast-induced downregulation of HIF-1α protein. Interestingly, GSK2606414, a PKR-like endoplasmic reticulum kinase (PERK) inhibitor, abrogates montelukast-induced downregulation of HIF-1α under hypoxic conditions. However, montelukast increases phosphorylation of eIF-2α at Ser51. Moreover, montelukast inhibits the proliferation of prostate cancer cells, which can be reversed by overexpression of HIF-1α protein. In conclusion, we identify montelukast may be used as a novel agent for the treatment of prostate cancer by decreasing HIF-1α protein translation.
| S-EPMC6067895 | biostudies-other
Project description:Canine prostate cancer (PC) is an aggressive disease, and dogs can be considered comparative models for human PC. In recent years, canine PC has been shown to resemble human castrate-resistant prostate cancer. The influx and efflux of testosterone in prostatic luminal cells are regulated by P-glycoprotein (P-gp). Therefore, human PC generally lacks P-gp expression and maintains the expression of androgen receptors (ARs). However, this co-expression has not previously been investigated in dogs. Therefore, this study aimed to evaluate AR and P-gp co-expression to elucidate these protein patterns in canine prostate samples. We identified AR/P-gp double immunofluorescence co-expression of both proteins in normal luminal cells. However, in canine PC, cells lack AR expression and exhibit increased P-gp expression. These results were confirmed by gene expression analyses. Overall, our results strongly suggest that normal canine prostate testosterone influx may be regulated by P-gp expression, and that during progression to PC, prostatic cells lack AR expression and P-gp overexpress. P-gp expression in canine PC may be related to a phenotype of multiple drug resistance.
| S-EPMC8835304 | biostudies-literature
Project description:12-Lipoxygenase, an arachidonic acid metabolizing enzyme of the lipoxygenase pathway, has been implicated as a major factor in promoting prostate cancer progression and metastasis. The ability of 12-LOX to aggravate the disease was linked to its proangiogenic role. Recent studies clearly demonstrated that 12-LOX enhances the expression and secretion of the angiogenic factor, vascular endothelial growth factor (VEGF) thus providing a direct link between this enzyme and its angiogenic properties. In the present study we have investigated the relationship between 12-LOX and hypoxia inducible factor-1alpha (HIF-1alpha), a transcription factor involved in the regulation of VEGF expression under hypoxic conditions in solid tumors. Our findings have revealed that HIF-1 is one of the target transcription factors regulated by 12-LOX and 12(S)-HETE, in hypoxic tumor cells of the prostate. Regulation of HIF-1alpha by 12-LOX adds to the complexity of pathways mediated by this enzyme in promoting prostate cancer angiogenesis and metastasis. We have evidence that 12-LOX increases the protein level, mRNA, and functional activity of HIF-1alpha under hypoxic conditions, one of the mechanisms by which it upregulates VEGF secretion and activity.
| S-EPMC3420817 | biostudies-other