Our results indicate that the intrinsic apoptosis pathway is activated in tumors from mice injected subcutaneously with HCMV-infected HepG2 cells which could participate to the restriction of tumor growth in addition to the anti-proliferative effect observed as measured by decreased Ki67 antigen expression and the restricted transforming capacities as measured by limited activation of the STAT3-cyclin D1 axis and reduced numbers of colonies in soft agar. The gene discussed is CCND1; the disease is neoplasm.