An update on RNA interference-mediated gene silencing in cancer therapy.

INTRODUCTION: Based on our previous review, this article presents the new progress in RNA interference (RNAi)-mediated gene silencing in cancer therapy, and reviews the hurdles and how they might be overcome. AREAS COVERED: RNAi-mediated gene silencing approaches have been demonstrated in humans, and ongoing clinical trials hold promise for treating cancer or providing alternatives to traditional chemotherapies. Here we describe the broad range of approaches to achieve targeted gene silencing for cancer therapy, discuss the progress made in developing RNAi as therapeutics for cancer and highlight challenges and emerging solutions associated with its clinical development. EXPERT OPINION: Although the field of RNAi-based cancer therapy is still an emerging one, we have yet to get solutions for overcoming all obstacles associated with its clinical development. The current rapid advances in development of new targeted delivery strategies and noninvasive imaging methods will be big steps to explore RNAi as a new and potent clinical modality in humans.