Tuesday, July 17, 2012

miRNA and Prostate Cancer

We have written a great deal about prostate cancer, PCa, and especially microRNAs. A recent paper by Yang et al present some new interesting results:

Recognition of micro-RNA function and their contribution to the biology of disease has given a new insight into disease mechanisms, with these discoveries potentially improving clinical diagnostic and therapeutic options. 

miR-125b has been identified as an important regulator in various cancers, including prostate cancer, but the mechanism of this regulation remains incompletely understood. In these studies, the effect of castration on miR-125b serum expression was evaluated in mice, simulating androgen deprivation. ...

A previously studied target of miR-125b, a regulator in the apoptotic pathway, BAK1, could not completely account for the role of miR-125b in prostate cancer. Thus, we looked for additional targets of miR-125b and found that NCOR2, which is a repressor of AR, is a direct target of miR-125b. We found that NCOR2 protein expression was blocked by mimics of miR-125b, and a luciferase binding assay confirmed that NCOR2 is a direct target of miR-125b. Our data provide novel evidence that miR-125b is an important regulator of the AR with specific ramification for the effectiveness of antiandrogens and other hormonal therapies in prostate cancer. 

We have discussed the significant potential of these small 22 base pair RNAs that can interfere with well defined pathways. This is an interesting example and worth following as a model.