CASP3 and neoplasm: In agreement with the in vitro experiments, administration of M1 alone in Huh-7 derived xenografts at a higher dose (8.7 × 107 PFU/day) significantly repressed the growth of Huh-7-derived xenografts, based on size of the tumor (Figure 4C), slowed tumor growth (Figure 4D), increased the level of cleaved Caspase 3, and decreased the level of Ki-67, a marker of cell proliferation (Figure 4E and 4F).