A Single Therapeutic miRNA Rescues the Oncolysis of Androgen Activated Prostate Specific Virus in Androgen Independent Cell Model

摘要

Prostate specific conditionally replicating adenoviruses (CRAd) are made by placing a tissue specific promoter upstream of one or more of the viral genes required for replication (e.g., E1A, E1B). However, one major problem associated with these vectors is their dependency for androgen receptor (AR), to transactivate the immediate early gene of the virus. This absolute necessity of androgens for prostate specific promoters renders them less useful in patients that have undergone or are currently on total androgen ablation therapy. Therefore, an alternative approach is needed for the existing vectors to be useful in clinical settings. To overcome this problem, we have generated a prostate specific CRAd by introducing a single therapeutic miRNA (miR-34c) that was identified in our library screen to synergize with viral oncolysis. Overexpression of miR-34c from the backbone of virus not only helped in suppressing the proliferation of AR positive cells but also rescued the oncolysis of androgen activated prostate specific virus in androgen independent cell model. To our knowledge this is the first report describing the utility of a single therapeutic miRNA construct to rescue viral oncolysis in advanced androgen resistant AR negative prostate cancer cell line model.