DHTKD1 and prostate cancer: A previous study demonstrated that insertion of the Arg-Gly-Asp (RGD) peptide into the HI loop of the fiber knob domain enhanced the adenovirus mediated gene transduction in CAR-negative cells through the binding of the RGD peptide to integrins on the target cells.[14] Thus, in this study, we evaluated the therapeutic efficacy of the E1A/E1B double mutant oncolytic adenovirus, AxdAdB-3, with Arg-Gly-Asp (RGD)-fiber modification (AxdAdB3-F/RGD) in prostate cancer in vitro and in nude mice.