Project description:Background: There is no cure for castration-recurrent prostate cancer (CRPC) and the mechanisms underlying this stage of the disease are unknown. Methods: We analyzed the transcriptome of human LNCaP prostate cancer cells as they progress to CRPC in vivo using replicate LongSAGE libraries. We refer to these libraries as the LNCaP atlas and compared these gene expression profiles with current suggested models of CRPC. Results: Three million tags were sequenced using in vivo samples at various stages of hormonal progression to reveal 96 novel genes differentially expressed in CRPC. Thirty-one genes encode proteins that are either secreted or are located at the plasma membrane, 21 genes changed levels of expression in response to androgen, and 8 genes have enriched expression in the prostate. Expression of 26, 6, 12, and 15 genes have previously been linked to prostate cancer, Gleason grade, progression, and metastasis, respectively. Expression profiles of genes in CRPC support a role for the transcriptional activity of the androgen receptor (CCNH, CUEDC2, FLNA, PSMA7), steroid synthesis and metabolism (DHCR24, DHRS7, ELOVL5, HSD17B4, OPRK1), neuroendocrine (ENO2, MAOA, OPRK1, S100A10, TRPM8), and proliferation (GAS5, GNB2L1, MT-ND3, NKX3-1, PCGEM1, PTGFR, STEAP1, TMEM30A), but neither supported nor discounted a role for cell survival genes. Conclusions: The in vivo gene expression atlas for LNCaP was sequenced and support a role for the androgen receptor in CRPC. BMC Medical Genomics 2010, 3:43 RNA from the hollow fibres of three mice (biological replicates) representing different stages of prostate cancer progression (AS, RAD, and CR) were used to make a total of nine LongSAGE libraries.
Project description:More effective therapeutic approaches for castration-resistant prostate cancer (CRPC) are urgently needed, thus reinforcing the need to understand how prostate tumors progress to castration resistance. We have established a novel mouse xenograft model of prostate cancer, KUCaP-2, which expresses the wild-type androgen receptor (AR) and which produces the prostate-specific antigen (PSA). In this model, tumors regress soon after castration, but then reproducibly restore their ability to proliferate after 1 to 2 months without AR mutation, mimicking the clinical behavior of CRPC. In the present study, we used this model to identify novel therapeutic targets for CRPC. Evaluating tumor tissues at various stages by gene expression profiling, we discovered that the prostaglandin E receptor EP4 subtype (EP4) was significantly upregulated during progression to castration resistance. Immunohistochemical results of human prostate cancer tissues confirmed that EP4 expression was higher in CRPC compared with hormone-naïve prostate cancer. Ectopic overexpression of EP4 in LNCaP cells (LNCaP-EP4 cells) drove proliferation and PSA production in the absence of androgen supplementation in vitro and in vivo. Androgen-independent proliferation of LNCaP-EP4 cells was suppressed when AR expression was attenuated by RNA interference. Treatment of LNCaP-EP4 cells with a specific EP4 antagonist, ONO-AE3-208, decreased intracellular cyclic AMP levels, suppressed PSA production in vitro, and inhibited castration-resistant growth of LNCaP-EP4 or KUCaP-2 tumors in vivo. Our findings reveal that EP4 overexpression, via AR activation, supports an important mechanism for castration-resistant progression of prostate cancer. Furthermore, they prompt further evaluation of EP4 antagonists as a novel therapeutic modality to treat CRPC. 4 samples in each group: androgen-dependent growth (AD), castration-induced regression nadir (ND), and castration-resistant regrowth (CR) stages
Project description:Background: There is no cure for castration-recurrent prostate cancer (CRPC) and the mechanisms underlying this stage of the disease are unknown. Methods: We analyzed the transcriptome of human LNCaP prostate cancer cells as they progress to CRPC in vivo using replicate LongSAGE libraries. We refer to these libraries as the LNCaP atlas and compared these gene expression profiles with current suggested models of CRPC. Results: Three million tags were sequenced using in vivo samples at various stages of hormonal progression to reveal 96 novel genes differentially expressed in CRPC. Thirty-one genes encode proteins that are either secreted or are located at the plasma membrane, 21 genes changed levels of expression in response to androgen, and 8 genes have enriched expression in the prostate. Expression of 26, 6, 12, and 15 genes have previously been linked to prostate cancer, Gleason grade, progression, and metastasis, respectively. Expression profiles of genes in CRPC support a role for the transcriptional activity of the androgen receptor (CCNH, CUEDC2, FLNA, PSMA7), steroid synthesis and metabolism (DHCR24, DHRS7, ELOVL5, HSD17B4, OPRK1), neuroendocrine (ENO2, MAOA, OPRK1, S100A10, TRPM8), and proliferation (GAS5, GNB2L1, MT-ND3, NKX3-1, PCGEM1, PTGFR, STEAP1, TMEM30A), but neither supported nor discounted a role for cell survival genes. Conclusions: The in vivo gene expression atlas for LNCaP was sequenced and support a role for the androgen receptor in CRPC. BMC Medical Genomics 2010, 3:43
Project description:More effective therapeutic approaches for castration-resistant prostate cancer (CRPC) are urgently needed, thus reinforcing the need to understand how prostate tumors progress to castration resistance. We have established a novel mouse xenograft model of prostate cancer, KUCaP-2, which expresses the wild-type androgen receptor (AR) and which produces the prostate-specific antigen (PSA). In this model, tumors regress soon after castration, but then reproducibly restore their ability to proliferate after 1 to 2 months without AR mutation, mimicking the clinical behavior of CRPC. In the present study, we used this model to identify novel therapeutic targets for CRPC. Evaluating tumor tissues at various stages by gene expression profiling, we discovered that the prostaglandin E receptor EP4 subtype (EP4) was significantly upregulated during progression to castration resistance. Immunohistochemical results of human prostate cancer tissues confirmed that EP4 expression was higher in CRPC compared with hormone-naïve prostate cancer. Ectopic overexpression of EP4 in LNCaP cells (LNCaP-EP4 cells) drove proliferation and PSA production in the absence of androgen supplementation in vitro and in vivo. Androgen-independent proliferation of LNCaP-EP4 cells was suppressed when AR expression was attenuated by RNA interference. Treatment of LNCaP-EP4 cells with a specific EP4 antagonist, ONO-AE3-208, decreased intracellular cyclic AMP levels, suppressed PSA production in vitro, and inhibited castration-resistant growth of LNCaP-EP4 or KUCaP-2 tumors in vivo. Our findings reveal that EP4 overexpression, via AR activation, supports an important mechanism for castration-resistant progression of prostate cancer. Furthermore, they prompt further evaluation of EP4 antagonists as a novel therapeutic modality to treat CRPC.
Project description:Xenografts are useful in vivo tumour models for investigating cancer progression, therapeutic responses and predicting anti-cancer drug response in patients with cancer of a similar phenotype. We have generated bulk RNA-seq data from LNCaP xenografts of a large and well-annotated prostate cancer progression study, investigating responsiveness and subsequent resistance to therapies targeting the androgen receptor (AR). LNCaP xenograft tumour establishment and initial growth are dependent on androgens in male mice (PRE-CX / pre-castration group). Upon castration, AR activity and tumour growth are suppressed (POST-CX / post-castration group), however, this initial responsiveness to castration reproducibly gives way to castration-resistance (CRPC / castration-resistant prostate cancer). Further treatment of CRPC with the AR targeting drug enzalutamide (ENZ) initially provides a therapeutic response (ENZ Sensitive; ENZS), however, resistance emerges in time (ENZ Resistant; ENZR).
Project description:EZH2 is frequently over-expressed in aggressive and metastatic solid tumors, including castration resistant prostate cancer (CRPC). We sought to determine EZH2-dependent gene expression programmes in prostate cancer progression, and found an intriguing functional switch of EZH2 from a repressor to an activator during CRPC development. We used microarrays to detail the global profiling of gene expression that are differentially regulated upon EZH2 depletion in two different prostate cancer cell lines. The androgen-dependent prostate cancer cell line LNCaP and the LNCaP-derived androgen-independent cell line LNCaP-abl (abl) were used for this study, as their transcription profiles strongly resemble that of clinical androgen-dependent and castration resistant prostate tumors, respectively. EZH2 was silenced by specific siRNAs in both cell lines, and total RNA was extracted and hybridized on Affymetrix microarrays.
Project description:Despite the clinical success of Androgen Receptor (AR)-targeted therapies, reactivation of AR signalling remains the main driver of castration-resistant prostate cancer (CRPC) progression. In this study, we performed a comprehensive unbiased characterisation of LNCaP cells chronically exposed to multiple AR inhibitors (ARI). Combined proteomics and metabolomics analyses implicated an acquired metabolic phenotype common in ARI-resistant cells and associated with perturbed glucose and lipid metabolism. To exploit this phenotype, we delineated a subset of proteins consistently associated with ARI resistance.
Project description:To identify molecular singnal alterations between androgen dependent prostate cancer and castration resistant prostate cancer, we performed interspecies comparative microarray analyses using RNAs prepared from uncastrasion and castration tumor from LNCAP Orhotopic xenograft models of prostate cancer. microarray data from uncastrasion and castration tumor revealed that the gene expression profile is most significantly altered in between androgen dependent prostate cancer and castration resistant prostate cancer. Comparative analyses of LNCAP Orhotopic xenograft models of prostate cancer showed that genes involved in androgen dependent and androgen independent tumor were significantly altered.
Project description:To identify molecular singnal alterations between androgen dependent prostate cancer and castration resistant prostate cancer, we performed interspecies comparative microarray analyses using RNAs prepared from uncastrasion and castration tumor from LNCAP Orhotopic xenograft models of prostate cancer. microarray data from uncastrasion and castration tumor revealed that the gene expression profile is most significantly altered in between androgen dependent prostate cancer and castration resistant prostate cancer. Comparative analyses of LNCAP Orhotopic xenograft models of prostate cancer showed that genes involved in androgen dependent and androgen independent tumor were significantly altered. We prepared RNA samples from 4 samples uncastrasion and 4 samples castration tumors from LNCAP Orhotopic xenograft models of prostate cancer . High-quality RNA samples were subjected to microarray analysis using the Affymetrix Human Gene 2.0 ST platform, and only those results that passed examinations for quality assurance and quality control of the Human Gene 2.0 ST arrays were retrieved. In total, we obtained gene expression profiles from the following samples: 4 samples uncastrasion and 4 samples castration tumors
Project description:hormonal progression in prostate cancer fiber model Experiment Overall Design: The LNCaP Hollow Fiber model of prostate cancer was appied. A total of 24 fibers were implanted in each animal, in bundles of eight fibers at three different regions in the animal. Castration of mice was performed At each time point, eight fibers from the same mouse were harvested and total RNA was isolated from LNCaP cells grown inside the fibers using Trizol