二烯丙基二硫诱导人胃癌MGC803细胞的分化

Diallyl disulfide induces differentiation of human gastric carcinoma MGC803 cell line

目的:研究二烯丙基二硫(DADS)诱导人胃癌MGC803 细胞分化作用及其机制. 方法:采用ConA凝集实验、碱性磷酸酶(ALP)比活性测定、免疫荧光染色细胞化学、免疫细胞化学及划痕标记荧光染料示踪技术(SLDT)等方法,观察DADS诱导人胃癌MGC803细胞分化的作用. 结果:人胃癌MGC803细胞对ConA的凝集率从79.1%下降为27.0%(x2=29.78,P<0.05);ALP比活性由2.00 nkat/g 降至0.67 nkat/g(F=207.6,P<0.05),下降率为66.1%; 细胞骨架蛋白呈细丝状,由胞核向胞质规则、放射状伸展,表明其合成增加与重组;SLDT表明人胃癌MGC803 细胞不显示荧光染料的传播,失去细胞间通讯功能, DADS处理后黄色荧光分布在伤沿细胞列和相邻的数列细胞内,表示细胞间通讯功能恢复.免疫细胞化学结果显示,p21WAF1表达增加,突变型p53、Ras-p21、C-myc 表达降低,而pRb表达无改变. 结论:DADS可以诱导MGC803细胞分化,癌基因与抑癌基因在此过程中起着重要作用.

AIM: To explore the differentiation induced by diallyl disul-fide (DADS) of human gastric carcinoma MGC803 cell line. METHODS: The DADS-induced differentiation of human gastric carcinoma MGC803 cells was examined by means of ConA-mediated cell agglutination, alkaline phosphatase activity detection, cytochemical and immunocytochemical staining, and scrape-loading/dye transfer technique (SLDT). RESULTS: After treated with DADS, ConA-mediated cell agglutination rate was significantly decreased (79.1% vs 27.0%, P<0.05). Specific alkaline phosphatase activity was decreased by 66.1 %, from 2.00 nkat/g to 0.67 nkat /g (F= 207.6, P<0.05). Filament-like cytoskeleton protein radiated regularly from the nuclei into cytoplasm, indicating its increased synthesis and reconstruction. SLDT revealed no dye transfer among MGC803 cells in the absence of DADS, while positive transfer of LY dye was found among the cells in the presence of DADS, suggesting that intercellular communication was restored. Immunocytochemisty showed that p21 WAF1 expression was increased, with mutant p53, Rasp21 and C-myc expression decreased and pRb unchanged. CONCLUSION: DADS can induce differentiation of MGC803 cells, in which oncogenes and anti-oncogenes may play important roles.