miR‐193b is an epigenetically regulated putative tumor suppressor in prostate cancer

Abstract

AbstractmiRNAs have proven to be key regulators of gene expression and are differentially expressed in various diseases, including cancer. Our aim was to identify epigenetically dysregulated genes in prostate cancer. We performed miRNA expression profiling after relieving epigenetic modifications in 6 prostate cancer cell lines and nonmalignant prostate epithelial cells. Thirty‐eight miRNAs showed increased expression in any prostate cancer cell line after 5‐aza‐2′‐deoxycytidine (5azadC) and trichostatin A (TSA) treatments. Six of these also had decreased expression in clinical prostate cancer samples compared to benign prostatic hyperplasia. Among these, miR‐193b was methylated in 22Rv1 cell line at a CpG island ∼1 kb upstream of the miRNA locus. Expressing miR‐193b in 22Rv1 cells using pre‐miR‐193b oligonucleotides caused a significant growth reduction (p < 0.001) resulting from a decrease of cells in S‐phase of the cell cycle (p < 0.01). In addition, the anchorage independent growth was partially inhibited in transiently miR‐193b‐expressing 22Rv1 cells (p < 0.01). Altogether, our data suggest that miR‐193b is an epigenetically silenced putative tumor suppressor in prostate cancer.

miR-193b Regulates Mcl-1 in Melanoma

“…27 For example, a recent study suggested that miR-193b is epigenetically silenced in prostate cancer cells. 28 Several technical issues arise in studies of this nature. One is the choice of control for the comparison of expression levels.…”

MicroRNAs as Regulators of Signal Transduction in Urological Tumors

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Reactivation of epigenetically silenced miR-512 and miR-373 sensitizes lung cancer cells to cisplatin and restricts tumor growth

“…9,10 Changes in DNA methylation status have been implicated in cancer-associated miR deregulation. [11][12][13] As a single miR often inhibits numerous mRNAs within a defined biological pathway, understanding the epigenetic regulation of miRs in cancer might facilitate the development of new cancer therapies.…”