Evaluation of Direct Effect of Testosterone on NGEP and LM O1 Expression in LNCaP Prostate Cancer Cells

Background: Androgens play a major role in the carcinogenesis of prostate cancer (PCa) and the growth of PCa cells is based on the level of androgens. New Gene Expressed in Prostate (NGEP) and LIM-domain-only1 (LMO1) are two proteins that seem to play important roles in prognosis and progress of PCa, respectively. Previous studies reported androgen-dependent NGEP and LMO1 translocation into the nucleus associated with androgen receptor in an androgen-dependent manner. However, the effects of natural androgens such as testosterone on NGEP and LMO1 gene expression have not been investigated and not clear whether androgens can affect NGEP and LMO1 gene expression. Objective: The aim of this study was to investigate the effect of testosterone on NGEP and LMO1 gene expression in PCa cells. Methods: We investigated NGEP, LMO1 and prostate specific antigen (PSA; as positive control) gene expression in LNCaP cells by Real Time RT-PCR in the presence of various testosterone concentrations (5,10, 20 and 50nM) after 24 and 48 hours of incubation. Results: Our results showed that NGEP gene expression was significantly increased in LNCaP cells in the presence of 5mM testosterone after 24 and 48hours, ~4.5 and 3.5 folds respectively in comparison with the control. The LMO1 expression was increased ~ 2.8 folds at 5nM testosterone after 48 hours of with the control. The LMO1 expression was increased ~ 2.8 folds at 5nM testosterone after 48 hours of incubation when compared with the control. Conclusion: Both NGEP and LMO1 up-regulations occurred at a limited range of testosterone concentration. This androgen dependency was relatively lower than that of PSA. Additional studies are required to clearly evaluate the effect of androgens on NGEP and LMO1 protein expression and functions.