Mitomycin C-induced fibroblast apoptosis and mechanism

Abstract

Objective To elucidate the mitomycin C (MMC) -induced apoptosis of fibroblasts and the mechanism. Methods The cultured fibroblasts were exposed for 12 h to 0-0. 3 g/L MMC, respectively. The cell proliferation was measured by CCK-8 assay and apoptotic cell death was analyzed by Ho-echst33342 stain on the fisherbrand covergla. The expression of Caspase-3 and the activation of p-ERK1/2, p-Akt were detected by Western blotting. Results Treatment of fibroblasts with MMC induced a significant decrease in proliferation. With the increases of MMC from 0. 001-0. 2 g/L MMC, Hoechst 33342 staining displayed nuclei with abnormal morphologies: bean-shaped nuclei with highly condensed chromatin or nuclei with irregular clumps of dense chromatin. 0.2g/L MMC, 100 nmol/L PD98059 (ERK kinase inhibitor) , 100 nmol/L LY294002 (AKT kinase inhibitor) induced a significant increase of Caspase-3 as compared with control group, accompanied by an increase in cell apoptosis. 0.2 g/L MMC, PD98059, LY294002 caused decrease of p-ERKl/2 and p-Akt. Conclusion 0. 2 g/L MMC can induce fibroblast apoptosis by reducing the phosphorylation of p-ERKl/2 and p-Akt, resulting in the increase in the Caspase-3 expression. MMC can inhibit fibroblast proliferation and induce its apoptosis, which may be one of mechanisms by which MMC prevents peridural adhesion after laminectomy. Key words: Fibroblast; Mitomycin C; Apoptosis