hIL-24 gene influences the biological characteristics of the keloid by regulating transforming growth factor-beta/Smad pathway / 中国组织工程研究

ABSTRACT

BACKGROUND:hIL-24, a tumor suppressor gene, can stimulate immune responses, inhibit the growth of tumor cel s, and the formation of tumor vessels, and induce cel apoptosis. OBJECTIVE:To explore the effects of hIL-24 gene on the proliferation and apoptosis of fibroblasts in the keloid and the underlying mechanisms. METHODS:Al the keloid specimens col ected from 13 patients were used for fibroblast culture and indentification. Fibroblast of the keloid was transfected with or without hlL-24 lentivirus. Subsequently, mRNA expressions of transforming growth factor-β, Smad3, proliferating cel nuclear antigen, matrix metal oproteinase-2,-9, and metal opeptidase inhibitor 1 were determined. RESULTS AND CONCLUSION:Immunofluorescent staining and flow cytometry showed that vimentin antibody was expressed positively in cytoplasma of fibroblast cultures, and the purity was more than 97.8%. Western blot assay showed that hIL-24 expression was significantly increased in the transfected fibroblasts. Quantitative PCR showed that the overexpression rate of hIL-24 in fibroblasts was 81.7%and mRNA expressions of transforming growth factor-β, Smad3, proliferating cel nuclear antigen, matrix metal oproteinase-2, and-9 were significantly decreased, while metal opeptidase inhibitor 1 mRNA expression was significantly increased in hIL-24 transfection group compared with control group (P<0.05). These findings suggest that hIL-24 gene inhibits the expressions of proliferating cel nuclear antigen, matrix metal oproteinase-2, and-9 in fibroblasts, and the underlying mechanism may involves TGF-β/Smad3 pathway.