MicroRNAs and their potential for translation in prostate cancer.
OBJECTIVE
Patients die of prostate cancer (CaP) because predictably after a period of response to androgen withdrawal, their CaP becomes castrate resistant. In this paper, we discuss the role that microRNAs (miRNAs) may play in this process.


METHODS
miRNAs are a group of endogenous, small non-coding RNA molecules that are thought to be responsible for the regulation of up to 30% of gene expression. The miRNA expression profile between androgen responsive and castrate resistant CaP cell lines is compared. Functional studies were carried out to identify the importance of the miRNA targets in controlling this process.


RESULTS
There were 17 differentially expressed miRNAs found, 10 up-regulated and 7 down-regulated. Among these, miRNA-125b was found to have the ability of rendering LNCaP cells resistant to androgen withdrawal. It was found to be androgen regulated and one of its targets, BAK1, was identified as being involved in how these CaP cells undergo apoptosis functionally.


CONCLUSIONS
miRNA-125b, at least in the CaP cell lines tested, is involved in the development of castrate resistance. While clearly this miRNA is only part of the answer, miRNAs may lead us in a new direction in trying to solve the central problem in CaP.
DeVere White
Ralph W
RW
Department of Urology, University of California, Davis, School of Medicine, Sacramento, CA 95817, USA. rwdeverewhite@ucdavis.edu
Vinall
Ruth L
RL
Tepper
Clifford G
CG
Shi
Xu-Bao
XB
D000728:Androgens / Q000378:metabolism; D015152:Blotting, Northern; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
D000728:Androgens; D035683:MicroRNAs