It is becoming clear that frequent epigenetic silencing of tumor suppressor genes could be responsible for the development of tumor in various organs. RASSF1A inactivation by methylation is associated with advanced grade and stage of prostate cancer and many other cancers. Therefore, restoration of RASSF1A in prostate cancer cells would restrict their growth. Our study suggests that mahanine can reverse the expression of an epigenetically silenced gene, RASSF1A in prostate cancer cells by inhibiting DNMT activity that in turn represses a key cell cycle regulator, cyclin D1 to inhibit cancer cell growth. Therefore, mahanine promises an encouraging therapeutic choice for prostatic cancer. Currently, we are investigating the efficacy of mahanine in vivo and exploring the molecular mechanism by which it re-activates RASSF1A in prostate cancer cells.