Project description:TCTP has been implicated in a plethora of important cellular processes related to cell growth, cell cycle progression, malignant transformation and inhibition of apoptosis. In addition to these intracellular functions, TCTP has extracellular functions and plays an important role in immune cells. TCTP expression was previously shown to be deregulated in prostate cancer, but its function in prostate cancer cells is largely unknown. Here we show that TCTP expression is regulated by androgens in LNCaP prostate cancer cells in vitro as well as human prostate cancer xenografts in vivo. Knockdown of TCTP reduced colony formation and increased apoptosis in LNCaP cells, implicating it as an important factor for prostate cancer cell growth. Global gene expression profiling in TCTP knockdown LNCaP cells showed that several interferon regulated genes are regulated by TCTP, suggesting that it may have a role in regulating immune function in prostate cancer. In addition, recombinant TCTP treatment increased colony formation in LNCaP cells suggesting that secreted TCTP may function as a proliferative factor in prostate cancer. These results suggest that TCTP may have a role in prostate cancer development.
Project description:TCTP has been implicated in a plethora of important cellular processes related to cell growth, cell cycle progression, malignant transformation and inhibition of apoptosis. In addition to these intracellular functions, TCTP has extracellular functions and plays an important role in immune cells. TCTP expression was previously shown to be deregulated in prostate cancer, but its function in prostate cancer cells is largely unknown. Here we show that TCTP expression is regulated by androgens in LNCaP prostate cancer cells in vitro as well as human prostate cancer xenografts in vivo. Knockdown of TCTP reduced colony formation and increased apoptosis in LNCaP cells, implicating it as an important factor for prostate cancer cell growth. Global gene expression profiling in TCTP knockdown LNCaP cells showed that several interferon regulated genes are regulated by TCTP, suggesting that it may have a role in regulating immune function in prostate cancer. In addition, recombinant TCTP treatment increased colony formation in LNCaP cells suggesting that secreted TCTP may function as a proliferative factor in prostate cancer. These results suggest that TCTP may have a role in prostate cancer development. A total of 6 samples were analyzed. These consisted of three biological replicates for each treatment. The samples transfected with siRNA against Luciferase (siLuc) served as controls.
Project description:Androgen receptor (AR) plays a central role in the development of prostate cancer. Increased expression of O-GlcNAc transferase (OGT) and O-GlcNAcylation are also implicated in metastatic prostate caner. We have identified VPRBP as a novel androgen-regulated gene and the stability of the encoded protein is regulated by OGT.VPRBP downregulation led to significant decrease in cell proliferation and p53 stabilization in LNCaPs. In this study, we employed chromatin immunoprecipitation coupled with massive parallel sequencing (ChIP-seq) to identify changes in p53 binding to the genome in VPRBP knockdown LNCaPs compared to scrambled siRNA transfected control cells. Stabilization of p53 was associated increased p53 recruitment to the chromatin.