Adenoviral Vector Expressing IL-24 Inhibit The Growth Of Laryngocarcinoma Cell Hep-2 In Vitro

Objective To study the effect of Ad-IL-24 in inhibiting growth of human laryngocarcinoma cell Hep-2.Methods: The IL-24 gene was transfected into human laryngeal cancer cell line Hep-2 and human diploid cell line WI-38 with a replication-incompetent adenovirus vector. The IL-24 gene was confirmed by RT-PCR in WI-38 and Hep-2 cells. Protein expression of IL-24 in WI-38 and Hep-2 cells was confirmed using Indirect Immunofluorescence. The cell growth and the apoptotic effect were tested by MTT assay,Hoechest 33258 staining,laser scanning confocal microscopy(LSCM) assay,flow cytometry assay and Western Blot assay.Results: IL-24 was proved successful expression both in Hep-2 cells and WI-38 cells. MTT assay and apoptosis test indicated Ad-IL-24 could induce growth suppression and apoptosis of Hep-2 cells. Cell cycle test revealed Ad-IL-24 could block Hep-2 cells in G2/M.Infection with Ad-IL-24 increased the phosphorylation of p38 MAPK and the activity of Caspase-3 in Hep-2. However, it has no effect on normal diploid cell WI-38.Conclusion: IL-24 gene can selectively inhibit the growth of Hep-2 cell and induces cell apoptosis. The apoptosis induced by IL-24 gene is through up regulating phosphorylation of p38MAPK and activation of mitochondria apoptosis pathway.