Project description:Analysis of enzalutamide- and/or olaparib-responsive gene expression in prostate cancer cells. The hypothesis tested in the present study was that enzalutamide influences the expression of genes that are involved in important bioprocesses in prostate cance rcells, including DNA damage response genes and this effect may synergize with poly(ADP-ribose) polymerase inhibitor olaparib in cytotoxicity to prstate cancer cells. prostate cancer cells were pretreated with enzalutamide or vehicle control DMSO for 24 h, followed by treatment with enzalutamide, olaparib, enzalutamide+olaparib, or vehicle control DMSO for 48 h. Gene expression in enzalutamide+olaparib-treated cells was compared with taht in vehicle control- and single agent-treated cells.
Project description:Analysis of enzalutamide- and/or olaparib-responsive gene expression in prostate cancer cells. The hypothesis tested in the present study was that enzalutamide influences the expression of genes that are involved in important bioprocesses in prostate cance rcells, including DNA damage response genes and this effect may synergize with poly(ADP-ribose) polymerase inhibitor olaparib in cytotoxicity to prstate cancer cells.
Project description:Enzalutamide, a second-generation androgen receptor (AR) antagonist, has demonstrated clinical benefit in men with prostate cancer. However, it only provides a temporary response and modest increase in survival, indicating a rapid evolution of resistance. Previous studies suggest that enzalutamide may function as a partial transcriptional agonist, but the underlying mechanisms for enzalutamide-induced transcription remain poorly understood. Here, we show that enzalutamide stimulates expression of a novel subset of genes distinct from androgen-responsive genes. Treatment of prostate cancer cells with enzalutamide enhances recruitment of pioneer factor GATA2, AR, Mediator subunits MED1 and MED14, and RNA Pol II to regulatory elements of enzalutamide-responsive genes. Mechanistically, GATA2 functions in directing AR, Mediator and Pol II loading to enzalutamide-responsive gene loci. Importantly, the GATA2 inhibitor K7174 inhibits enzalutamide-induced transcription by decreasing binding of the GATA2/AR/Mediator/Pol II transcriptional complex, contributing to sensitization of prostate cancer cells to enzalutamide treatment. Our findings provide mechanistic insight into the future combination of GATA2 inhibitors and enzalutamide for improved AR-targeted therapy.
Project description:Acquisition of resistance to the PARP inhibitor, Olaparib, constitutes a major challenge for the treatment of advanced prostate cancer. The purpose of this study was to identify molecular targets responsible for the development of acquired Olaparib resistance in advanced prostate cancer. Towards this goal, next-generation sequencing (NGS)-based gene expression profiling (RNA-Sequencing; RNA-Seq) was performed on castration-sensitive prostate cancer (CSPC)/Olaparib-sensitive LNCaP cells, castration-sensitive prostate cancer (CSPC)/Olaparib-resistant LN-OlapR cells, castration-resistant prostate cancer (CSPC)/Olaparib-sensitive C4-2B cells, and castration-resistant prostate cancer (CSPC)/Olaparib-resistant 2B-OlapR cells.
Project description:Prostate cancer C4-2B cells were cultured in enzalutamide in a dose-escalation manner. After sixty passages cells were resistant to enzalutamide, with a specific sets of genes been deregulated. We performed global gene expression analysis by cDNA microarrays to identify genes responsible for enzalutamide resistance in C4-2B-MDVR cells. Enzalutamide resistant C4-2B-MDVR cells were selected from C4-2B cells during long time enzalutamide treatment. Genes responsible for enzalutamide resistance were identified using C4-2B vs. C4-2B-MDVR RNA extraction and hybridization on Affymetrix microarrays.