Pan-cancer oncolytic virotherapy through disruption of tumor cell mitochondrial dynamics

Oxidative stress, a pervasive cancer vulnerability, remains a challenging therapeutic target attributed to tumor heterogeneity and adaptive resistance. Herein, we identify RhoA as a "redox rheostat" during oncolytic virotherapy by regulating mitochondrial dynamics, thereby addressing this bottleneck to enable pan-cancer therapy via oxidative-oncolytic synergy. Engineering an oncolytic virus to express RhoA (rNDV-RHOA) elicits robust oxidative mitophagic cell death with inherent tumor selectivity and demonstrates superior oncolysis in a comprehensive panel of preclinical cancer models spanning in vitro, ex vivo, and in vivo settings, including models evaluated under intravenous administration. The construct exhibits favorable safety profiles without inducing seroconversion, facilitating repeated systemic dosing. Mechanistically, RhoA drives mitochondrial fission to impair mitochondrial complex III, initiating oxidative stress while tempering it via mitophagy induction downstream of Akt/mTOR inhibition. Concurrently, viral infection serves as the decisive precipitating event that shifts the cellular response from adaptive mitophagy to mitochondrial catastrophe by enhancing complex I and V activities to promote ATP biosynthesis, thereby culminating in acute cell death characterized by a precipitous decline in mitochondrial mass and ATP bioavailability. This establishes rNDV-RHOA as an oncolytic virotherapy platform that transcends conventional oncolysis to surmount tumor heterogeneity by exploiting inherent tumor redox dependency.