Role of BH3-only gene in the oxaliplatin-induced apoptosis of colon cancer cells / 中华胃肠外科杂志

ABSTRACT

<p><b>OBJECTIVE</b>To study the role of BH3-only gene in oxaliplatin-induced apoptosis of human colon cancer cell line, and to explore the associated mechanisms.</p><p><b>METHODS</b>Two strains of human colon cancer cell line SW480 and HT29 were selected, and treated respectively with different concentrations of oxaliplatin (0.3, 0.6, 1.25, 2.5, 5, 10 and 20 mg/L). Cell growth and inhibition were detected by MTT method. Apoptosis was measured by flow cytometry. Bim and PUMA expressions were examined by fluorescence quantitative PCR.</p><p><b>RESULTS</b>After treatment of different oxaliplatin concentrations in human colon carcinoma cells SW480 line, the cell growth was inhibited in a dose-dependent manner, while Bim and PUMA expressions were significantly up-regulated. While HT29 cell lines received the same treatment, no obvious inhibition of cell growth and up-regulation of Bim and PUMA expression were found. When SW480 cells were exposed to 5 mg/L and 10 mg/L of oxaliplatin for 24 h, the early apoptotic rates were (4.87±0.55)% and (12.10±1.04)%; for 48 h, the early apoptotic rates were (11.47±0.85)% and (30.07±2.01)%; for 72 h, the early apoptotic rates were (28.99±2.12)% and (38.32±3.15)% respectively, which were all significantly higher than those in control group [(0.30±0.10)%, (0.40±0.10)% and (0.50±0.20)%, all P<0.01]. In HT29 cells, the differences of apoptotic rates between oxaliplatin treatment group and control group were not statistically significant (all P>0.05).</p><p><b>CONCLUSIONS</b>Oxaliplatin can inhibit colon cancer cell line SW480 growth and induce apoptosis. Induction of apoptosis of colon cancer cells by oxaliplatin may be associated with the up-regulation of BH3-only proteins, Bim and PUMA.</p>