ABSTRACT
Either as causative agents or responsive elements, microRNAs are differentially expressed in prostate cancer. However, microRNA profiling in prostate cancer has been fraught with discrepancies across studies owing to differences in the profiling technologies used, and in the prostate cancer samples that have been profiled. There is very little overlap although a few microRNAs such as miR-125, miR-100, let-7 seem to recur as differentially expressed microRNAs in prostate tumors compared to normal prostate tissue. The validated targets of some of the differentially expressed microRNAs are either proliferation genes or pro-apoptotic/growth inhibitory genes, suggesting their implication in cancer. Clearly, microRNA profiling technologies need to be better standardized and validated accurately in order to facilitate the discovery of diagnostic and prognostic molecular biomarkers for prostate cancer. microRNAs are also differentially expressed between androgen responsive and androgen refractory prostate cancers, although again there are only a few overlaps across studies. Androgen also seems to regulate the expression of microRNAs. The discovery of a microRNA-mediated androgen signaling pathway may prove invaluable to the treatment of androgen-refractory prostate cancer.
