【摘要】 目的探讨重离子诱导人肝癌细胞:3MMC-7721细胞凋亡及bal-2／bax的表达在重离子治癌中的作用。方法应用流式细胞技术、MTT法及免疫组化法,观察重离子诱导人肝癌细胞SMMC-7721细胞凋亡和bal-2／bax表达的情况,并应用AO／BE荧光染色,在荧光显微镜下,观察各组织细胞凋亡的形态学变化。结果经MTT比色法测定细胞增殖能力,可见随辐射剂量的增加,细胞存活率逐渐降低。流式细胞仪检测重离子对SMMC-7721细胞的DNA含量变化,结果显示2．0、3．0 Gy组的SMMC-7721细胞在G2／M期所占细胞比率较对照组及1．0、1．5Gy组增高(P<0．01)。免疫组化法观察随辐射剂量的增加,bax的表达显著上调,而bcl-2的表达则受抑制。结论重离子能在体外诱导SMMC-7721细胞凋亡,且具有剂量依赖性;重离子在一定剂量时,使细胞增殖能力降低;重离子能诱导SMMC-7721细胞bax蛋白表达上调,而bcl-2表达降低,从而诱导细胞凋亡。更多还原

【Abstract】 Objective To study the effects of heavy ion irradiation on apoptosis and bcl-2/bax expression in human hepatoma cell SMMC-7721. Methods Exponentially growing human hep-atoma cell SMMC-7721 cultured in vitro was irradiated with a 12C ion beam of 44.56 keV/μm) at doses varying from 0 to 3.0 Gy. Survival fractions of irradiated cells at various doses were measured by MTT assay. Apoptotic cells after irradiation were analyzed by fluorescent microscopy and flow cytometry. Expression of bcl-2/bax genes in the irradiated cells was detected by im-munohistological assay. Results The viability of SMMC-7721 cells decreased gradually with the dosage of carbon ion beam increase(P < 0.05 vs. control). Carbon ion irradiation efficiently induced cell apoptosis and significantly up-regulated the expression of bax gene and down-regulated the expression bcl-2 gene. Conclusion High-LET heavy ion beam could induce cell apoptosis effectively at certain dosage. The apoptosis rate was correlated with the expression of bcl-2/bax.更多还原