Expression of adenovirus-mediated melanoma differentiation-associated-7/interleukin-24 mRNA in hepatocellular carcinoma cell lines of HepG2, Hep3B and MHCC97L and human normal liver cell line L02. Cells were infected with 10 multiplicity of infection of Ad.IL-24, SG600-EGFP, SG600-IL24,harvested at 24 h, treated as described in “Materials and Methods”. A: Lanes 1, 2, 3, 4: Ad.IL-24 group, SG600-EGFP group, control group and SG600-IL24 group; B: β-actin corresponsively.