An HSV engineered to express tumor-necrosis-factor-related apoptosis-inducing ligand (TRAIL) allowed the targeting of a broader tumor cell population by combining the effect of direct HSV-mediated oncolysis and TRAIL-mediated apoptosis induction, irrespective of the differential susceptibility of tumor cells to either modes of cell death [166]. The gene discussed is TNFSF10; the disease is neoplasm.