Metformin regulated genes in human prostate cancer cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE196343 | GEO | 2022/02/10
REPOSITORIES: GEO
Similar Datasets
Project description:LSD1 (also known as KDM1A) is a histone demethylase and a key regulator of gene expression in embryonic stem cells and cancer. LSD1 was initially identified as a transcriptional repressor via its demethylation of active histone H3 marks (di-methyl lysine 4 [2MK4]). In prostate cancer, specifically, LSD1 also co-localizes with the AR and demethylates repressive 2MK9 histone marks from androgen-responsive AR target genes, facilitating androgen-mediated induction of AR-regulated gene expression and androgen-induced proliferation in androgen-dependent cancers. Recently, it was shown that treatment with high doses of androgens (e.g.10-fold higher doses than those required for induction of expression of androgen-activated genes such as PSA) recruits LSD1 and AR to an enhancer within the AR; this AR and LSD1 recruitment represses AR transcription. Thus, LSD1 appears to play a role in mediating both the proliferative and repressive phases of the biphasic androgen dose-response curve. For these reasons, we hypothesized that LSD1 might be important for maintenance of AR signalling in castration-resistant prostate cancer (CRPC) tumors. However, in this report, we describe a distinct role of LSD1 as a driver of proliferation and survival of prostate cancer cells, including CRPC cells, irrespective of androgens or even AR expression. Specifically, LSD1 activates expression of cell cycle, mitosis, and embryonic stem cell maintenance pathways that are enriched in lethal prostate cancers - pathways not activated by androgens. Finally, we observe that treatment with a new LSD1 inhibitor potently and specifically suppresses LSD1 function and suppresses CRPC growth and survival in vitro and in vivo. Our data place LSD1 as a key driver of androgen-independent survival in lethal prostate cancers and demonstrate the potential of LSD1-directed therapies in the near-term. The enclosed files are from microarrays experiments after suppressing LSD1 with RNAi or stimulating cells with the androgen agonist dihydrotestosterone (DHT).
2016-06-30 | E-GEOD-61630 | biostudies-arrayexpress
Project description:Although the vital role of the androgen receptor (AR) has been well demonstrated in primary prostate cancers, its role in the androgen-insensitive prostate cancers still remains unclear. Here, we used a small hairpin RNA approach to directly assess AR activity in prostate cancer cells. Reduction of AR expression in the two androgen-sensitive prostate cancer cell lines, LNCaP and LAPC4, significantly decreased AR-mediated transcription and cell growth. Intriguingly, in two androgen-insensitive prostate cell lines, LNCaP-C42B4 and CWR22Rv1, knockdown of AR expression showed a more pronounced effect on AR-induced transcription and cell growth than androgen depletion. Using cDNA microarrays, we also compared the transcriptional profiles induced by either androgen depletion or AR knockdown. Although a significant number of transcripts appear to be regulated by both androgen depletion and AR knockdown, we observed a subset of transcripts affected only by androgen depletion but not by AR knockdown, and vice versa. Finally, we demonstrated a direct role for AR in promoting tumor formation and growth in a xenograft model. Taken together, our results elucidate an important role for the AR in androgen-insensitive prostate cancer cells, and suggest that AR can be used as a therapeutic target for androgen-insensitive prostate cancers.
2007-05-04 | E-SMDB-4028 | biostudies-arrayexpress
Project description:Background: Castration-resistant prostate cancer (CRPC) represents a therapeutic challenge for current medications. Methods: In order to explore the molecular mechanisms involved in CRPC progression and to identify new therapeutic targets, we analyzed a unique sample set of 11 castration-resistant prostate cancers and 7 advanced tumors by array-CGH and gene expression microarrays. The genome-wide DNA and RNA data were integrated to identify genes whose overexpression was driven by their amplification. To assess the functional role of these genes, their expression was analyzed in a transcriptional dataset of 329 clinical prostate cancers and the corresponding gene products were silenced using RNA interference in prostate cancer cells. Results: Six recurrent genetic targets were identified in the CRPCs; ATP1B1, AR, FAM110B, LAS1L, MYC and YIPF6. In addition to AR and MYC, FAM110B emerged as a potential key gene involved in CRPC progression in a subset of the tumors. FAM110B was able to regulate AR signaling in prostate cancer cells and FAM110B itself was regulated by androgens. FAM110B siRNA inhibited the growth of prostate cancer cells in vitro, and this effect was substantially enhanced in androgen deficient conditions. Ectopic FAM110B expression in non-cancerous epithelial prostate cells induced aneuploidy and impaired antigen presentation. Conclusions: The DNA / RNA gene outlier detection combined with siRNA cell proliferation assay identified FAM110B as a potential growth promoting key gene for CRPC. FAM110B appears to have a key role in the androgen signaling and progression of CRPC impacting multiple cancer hallmarks and therefore highlighting a potential therapeutic target.
2011-08-29 | GSE28403 | GEO
Project description:Although the vital role of the androgen receptor (AR) has been well demonstrated in primary prostate cancers, its role in the androgen-insensitive prostate cancers still remains unclear. Here, we used a small hairpin RNA approach to directly assess AR activity in prostate cancer cells. Reduction of AR expression in the two androgen-sensitive prostate cancer cell lines, LNCaP and LAPC4, significantly decreased AR-mediated transcription and cell growth. Intriguingly, in two androgen-insensitive prostate cell lines, LNCaP-C42B4 and CWR22Rv1, knockdown of AR expression showed a more pronounced effect on AR-induced transcription and cell growth than androgen depletion. Using cDNA microarrays, we also compared the transcriptional profiles induced by either androgen depletion or AR knockdown. Although a significant number of transcripts appear to be regulated by both androgen depletion and AR knockdown, we observed a subset of transcripts affected only by androgen depletion but not by AR knockdown, and vice versa. Finally, we demonstrated a direct role for AR in promoting tumor formation and growth in a xenograft model. Taken together, our results elucidate an important role for the AR in androgen-insensitive prostate cancer cells, and suggest that AR can be used as a therapeutic target for androgen-insensitive prostate cancers. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Keywords: Logical Set Computed
2007-08-08 | E-GEOD-7585 | biostudies-arrayexpress
Project description:LSD1 (also known as KDM1A) is a histone demethylase and a key regulator of gene expression in embryonic stem cells and cancer.1,2 LSD1 was initially identified as a transcriptional repressor via its demethylation of active histone H3 marks (di-methyl lysine 4 [2MK4]).1 In prostate cancer, specifically, LSD1 also co-localizes with the AR and demethylates repressive 2MK9 histone marks from androgen-responsive AR target genes, facilitating androgen-mediated induction of AR-regulated gene expression and androgen-induced proliferation in androgen-dependent cancers.3,4 Recently, it was shown that treatment with high doses of androgens (e.g.10-fold higher doses than those required for induction of expression of androgen-activated genes such as PSA) recruits LSD1 and AR to an enhancer within the AR; this AR and LSD1 recruitment represses AR transcription.5 Thus, LSD1 appears to play a role in mediating both the proliferative and repressive phases of the biphasic androgen dose-response curve. For these reasons, we hypothesized that LSD1 might be important for maintenance of AR signaling in castration-resistant prostate cancer (CRPC) tumors. However, in this report, we describe a distinct role of LSD1 as a driver of proliferation and survival of prostate cancer cells, including CRPC cells, irrespective of androgens or even AR expression. Specifically, LSD1 activates expression of cell cycle, mitosis, and embryonic stem cell maintenance pathways that are enriched in lethal prostate cancers – pathways not activated by androgens. Finally, we observe that treatment with a new LSD1 inhibitor potently and specifically suppresses LSD1 function and suppresses CRPC growth and survival in vitro and in vivo. Our data place LSD1 as a key driver of androgen-independent survival in lethal prostate cancers and demonstrate the potential of LSD1-directed therapies in the near-term.
2016-06-30 | GSE61630 | GEO
Project description:Metformin is a classic type II diabetes drug which has possessed anti-tumor properties for various cancers. However, different cancers do not respond to metformin with the same effectiveness or acquire resistance. Thus, searching for vulnerabilities of metformin-resistant prostate cancer is a promising strategy to improve the therapeutic efficiency. A genome-scale CRISPR-Cas9 activation library targeting 23430 genes is conducted to identify the genes that confer resistance to metformin in prostate cancer cells.
2020-10-14 | GSE159467 | GEO
Project description:Androgen receptor (AR) orchestrates an intricate transcriptional regulatory network that governs prostate cancer initiation, development and progression. To understand this network in detail, we generated genome-wide maps of AR occupancy by ChIP-seq in LNCaP cells. We found NKX3-1, an androgen-dependent homeobox protein well-characterized for its role in prostate development and differentiation, being recruited to AR binding sites (ARBS) in response to androgen signaling. We identified 6,359 NKX3-1 binding sites, most of which overlapped with AR. In addition to its novel collaborative transcriptional role at well-known prostate cancer model genes, our binding and knockdown studies further suggested that NKX3-1 potentially regulates AR in a feed-forward manner. Integrative analysis of Oncomine molecular concepts showed that these androgen-regulated AR and NKX3-1 associated genes are significantly overexpressed in prostate carcinoma as well as advanced and recurrent prostate tumors. From our transcriptomic profiling and Gene Ontology analysis, we observed that AR and NKX3-1 co-regulate genes involved in "protein trafficking" processes, which are mandatory events in the integration of oncogenic signaling pathways leading to prostate cancer development and progression. Interestingly, we found that AR and NKX3-1 co-regulate several members of the RAB GTPase family of secretory/trafficking proteins via the involvement of FoxA1 in a ternary complex and we believe that these AR/NKX3-1/FoxA1 co-regulated RAB genes could serve as expression signatures in prostate carcinogenesis. More specifically, through functional analyses, we showed that NKX3-1, together with AR and FoxA1, could promote prostate cancer cell survival through activation of RAB3B expression. Collectively, our study has provided important insights into the hierarchical transcriptional regulatory network established between AR and NKX3-1 and sought to elucidate the important genetic-molecular-phenotypic paradigm in androgen-dependent prostate cancer. Genome-wide binding analyses of AR, NKX3-1 and FoxA1 in LNCaP with or without DHT (5alpha-dihydrotestosterone) stimulation using ChIP-Seq.
2011-11-16 | E-GEOD-28264 | biostudies-arrayexpress
Project description:Androgen receptor (AR) is a hormone-activated transcription factor that plays important roles in prostate development, function, as well as malignant transformation. The downstream pathways of AR, however, are incompletely understood. AR has been primarily known as a transcriptional activator inducing prostate-specific gene expression. Through integrative analysis of genome-wide AR occupancy and androgen-regulated gene expression, here we report AR as a globally acting transcriptional repressor. This repression is mediated by androgen responsive elements (ARE) and dictated by Polycomb group protein EZH2 and repressive chromatin remodeling. In embryonic stem cells, AR-repressed genes are occupied by EZH2 and harbor bivalent H3K4me3 and H3K27me3 modifications that are characteristic of differentiation regulators, the silencing of which maintains the undifferentiated state. Concordantly, these genes are silenced in castration-resistant prostate cancer rendering a stem cell-like lack of differentiation and tumor progression. Collectively, our data reveal an unexpected role of AR as a transcriptional repressor inhibiting non-prostatic differentiation and, upon excessive signaling, resulting in cancerous de-differentiation. It provides an innovative mechanism for castration resistance and highlights novel therapeutic strategies to treat advanced prostate cancer. Keywords: Genetic Modification compare gene expression in different cell lines with or without androgen treatment or EZH2 knockdown
2011-12-11 | E-GEOD-31978 | biostudies-arrayexpress
Project description:Androgen receptor (AR) orchestrates an intricate transcriptional regulatory network that governs prostate cancer initiation, development and progression. To understand this network in detail, we generated genome-wide maps of AR occupancy by ChIP-seq in LNCaP cells. We found NKX3-1, an androgen-dependent homeobox protein well-characterized for its role in prostate development and differentiation, being recruited to AR binding sites (ARBS) in response to androgen signaling. We identified 6,359 NKX3-1 binding sites, most of which overlapped with AR. In addition to its novel collaborative transcriptional role at well-known prostate cancer model genes, our binding and knockdown studies further suggested that NKX3-1 potentially regulates AR in a feed-forward manner. Integrative analysis of Oncomine molecular concepts showed that these androgen-regulated AR and NKX3-1 associated genes are significantly overexpressed in prostate carcinoma as well as advanced and recurrent prostate tumors. From our transcriptomic profiling and Gene Ontology analysis, we observed that AR and NKX3-1 co-regulate genes involved in ‘protein trafficking’ processes, which are mandatory events in the integration of oncogenic signaling pathways leading to prostate cancer development and progression. Interestingly, we found that AR and NKX3-1 co-regulate several members of the RAB GTPase family of secretory/trafficking proteins via the involvement of FoxA1 in a ternary complex and we believe that these AR/NKX3-1/FoxA1 co-regulated RAB genes could serve as expression signatures in prostate carcinogenesis. More specifically, through functional analyses, we showed that NKX3-1, together with AR and FoxA1, could promote prostate cancer cell survival through activation of RAB3B expression. Collectively, our study has provided important insights into the hierarchical transcriptional regulatory network established between AR and NKX3-1 and sought to elucidate the important genetic-molecular-phenotypic paradigm in androgen-dependent prostate cancer. Gene expression profiling of LNCaP in response to ETOH (vehicle) or DHT (5α-dihydrotestosterone) stimulation across different treatment time-points using microarray.
2011-11-16 | E-GEOD-28596 | biostudies-arrayexpress
Project description:Aberrant activation of androgen receptor (AR)-dependent transcriptional programs is a hallmark of human prostate cancers. At the molecular level, ligand-mediated AR activation is coordinated through spatial and temporal protein-protein interactions (PPIs) involving AR-interacting proteins, which we designate the “AR-interactome”. Despite many years of research, the ligand-sensitive protein complexes involved in ligand-mediated AR activation in prostate-tumor cells has not been clearly defined. Here, we describe the development, characterization, and utilization of a novel human LNCaP prostate-tumor cell line, N-AR, which stably expresses wild-type AR containing the streptavidin-binding peptide epitope tagged at its N-terminus (SBP-AR). A bioanalytical workflow involving streptavidin-chromatography and label-free quantitative mass spectrometry was used to identify SBP-AR and associated ligand-sensitive proteins/protein complexes functionally linked to AR activation in the cytosol of N-AR cells. Functional studies verified that ligand-sensitive streptavidin-copurified proteins encoded modulators of AR-mediated transcription, suggesting that these novel proteins were putative SBP-AR-interacting proteins in N-AR cells. This was supported by biochemical associations between recombinant SBP-AR and the ligand-sensitive COPI retrograde trafficking complex in vitro. Extensive biochemical and molecular experiments showed that the COPI-retrograde complex regulates ligand-mediated AR transcriptional activation through the mobilization of Golgi-localized ARA160 coactivator into the nuclear compartment of prostate-tumor cells. Collectively, this study provides a bioanalytical strategy to validate the AR-interactome and define novel AR-interacting proteins involved in ligand-mediated AR activation in prostate-tumor cells. Moreover, we describe a cellular system to study how compartment-specific AR-interacting proteins influence AR activation and contribute to aberrant AR-dependent transcription that underlies the majority of human prostate cancers.
2016-07-20 | PXD002861 | Pride