[Melanoma differentiation associated gene-7 and interleukin-24 selectively induces growth arrest and apoptosis in hepatocellular carcinoma cell lines in vitro].

OBJECTIVE: To investigate the effect of melanoma differentiation associated gene-7/interleukin-24 (mda-7/IL-24) on the hepatocellular carcinoma cell lines and normal liver cell line in vitro. METHODS: Hepatocellular carcinoma cell lines HepG2, SMMC7721, Hep3B, MHCC97L, M6 and normal liver cell line L02 were infected with Ad.mda-7. The gene expression of mda-7/IL-24 in these cell lines was confirmed by RT-PCR and ELISA assay. MTT assay and flow cytometry were used to study tumor cell proliferation and cell cycle in vitro. Hoechst staining and cytometry assay after Annexin-V and PI staining were studied to indicate the apoptosis effect. RESULTS: It was confirmed by RT-PCR that the exogenous mda-7/IL-24 gene expressed in all of these cells. The mda-7/IL-24 protein product was confirmed by assaying the supernatant with ELISA. MTT and apoptosis test indicated mda-7/IL-24 can induce the hepatocellular carcinoma cell lines growth suppression, apoptosis in vitro but not in normal liver cell line L02, cell cycle test revealed mda-7/IL-24 can block cancer cell lines in G2/M but not in L02. CONCLUSIONS: mda-7/IL-24 selectively induces growth suppression, apoptosis in hepatocellular carcinoma lines but not in normal liver cell in vitro.