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.
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.
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.
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.
Project description:Investigation if GATA-2 and NKX3-1 exogenous expression in prostate basal-like prostate epithelial cells could induce AR transcription and luminal differentiation
Project description:While tissue and lineage-specific super-enhancers (SEs) regulate cell fate decision during development, the nature of Castration Resistant Prostate Cancer (CRPC)-specific SEs (CSEs) that drive resistance to AR-targeted therapies is unknown. Herein we report the lysine 13 (K13)-acetylation of Homeodomain transcription factor HOXB13 as a critical feature underlying CSE exclusivity. The histone acetyltransferase (HAT) CBP/p300 specifically acetylates HOXB13 (acK13-HOXB13) in prostate cancer cells. The acK13-HOXB13 enriched CSEs sprout at critical lineage genes such as the NKX3-1, Androgen receptor (AR), AR regulator ACK1/TNK2 a tyrosine-kinase and tyrosine kinase ligands associated with angiogenesis, including VEGFA and ANGPT2/ANGPTL3 to expedite prostate tumor autonomy.
Project description:Androgen receptor (AR) plays an essential role in normal prostate development and prostate cancer (PCa) progression. To understand the role of AR at the single-cell level, we performed single-cell transcriptome analysis on PCa cells stimulated with androgen and antiandrogen to reconstruct the dynamic and direct AR transcriptional network. Our work reveals that androgen stimulates the ER and Golgi stress response , promoting secreting protein trafficking, and inhibiting cell apoptosis. Moreover, we identify an ER-to-Golgi protein vesicle-mediated transport gene signature essential for maximal androgen-mediated ER-Golgi trafficking, cell proliferation, and association with PCa prognosis and progression. Notably, we show that AR collaborates with CREB3L2, XXX, to coordinately promote ER-Golgi trafficking of Golgi enzyme Mannosidase II and PCa cell survival. Finally, we show the inhibition of the ER-Golgi transport process with Brefeldin A leads to tumor regression. Our study collectively reveals the heterogeneity of PCa cell transcriptional response to androgen stimulation, demonstrates a functional role for increased ER-Golgi trafficking process, and provides a mechanism for how the process is augmented in PCa as well as the potential of targeting may provide novel treatment strategies.
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.
Project description:Prostate carcinogenesis is associated with changes in androgen signaling from driving cellular differentiation to promoting oncogenic behaviors. RUNX2 binds the androgen receptor (AR), and ectopic expression of RUNX2 is linked to prostate cancer (PCa) progression. We therefore investigated genome-wide the influence of RUNX2 on androgen-induced gene expression and AR DNA binding in PCa cells. The predominant function of RUNX2 is to inhibit the androgen response, attributable in part to dissociation of AR from target genes such as the tumor suppressor NKX3-1. At a minority of AR target genes, however, AR activity persists in the presence of RUNX2. Some of these genes are co-operatively stimulated by androgen and RUNX2 signaling and are characterized by the presence of putative enhancers co-occupied by AR and RUNX2. Genes synergistically stimulated by AR and RUNX2 include the invasion-promoting transcription factor SNAI2. Indeed, co-activation of AR and RUNX2, but neither alone, stimulated PCa cell invasiveness, which was abolished by SNAI2 silencing. Accordingly, PCa biopsies most strongly stained for SNAI2 exhibit high nuclear expression of both RUNX2 and AR. The RUNX2-mediated locus-dependent modulation of AR activity in PCa opens a research avenue that may guide the development of novel diagnostic and therapeutic approaches to patient management. total RNA from C4-2B/Rx2dox cells was extracted in biological triplicates from four different conditions. Ethanol vehicle control, dox to induce RUNX2 expression, DHT to activate androgen receptor and DHT+dox combined.