核黄素光化学反应诱导人胃癌细胞凋亡  

Apoptosis of Human Gastric Cancer Cell Induced by Photochemical Riboflavin

作　　者：李锦全[1] 陈瑞川[2] 蔡克瑕[2] 叶志云[1] 

机构地区：[1]厦门大学生命科学学院生物系,福建厦门361005 [2]厦门大学生命科学学院抗癌研究中心,福建厦门361005

出　　处：《癌症》2003年第3期253-256,共4页Chinese Journal of Cancer

基　　金：福建省自然科学基金项目(C97108)

摘　　要：背景与目的:核黄素在光照下具有抑癌活性,并且被认为与核黄素光化学反应产生的活性氧自由基有关。本研究探讨核黄素在光照处理下,体外诱导人胃癌MGC80-3细胞凋亡效应。方法:以台盼蓝拒染法计数细胞存活率,Giemsa染色观察形态改变,DNA琼脂糖电泳分析DNA片段化,测定断裂及未断裂DNA含量定量凋亡效率,流式细胞术及Westernblot分别检测细胞周期及凋亡相关基因表达变化。结果:细胞存活率依浓度及处理时间而下降;光照核黄素处理24h,细胞呈典型的凋亡形态;以10、20、30和40μmol/L的核黄素光照处理MGC80-3细胞,DNA电泳显示20μmol/L以上处理组均出现典型的凋亡DNA梯形带;且相应凋亡效率分别为35.4%、54.1%、70.6%和86.8%,与核黄素的浓度呈正相关;经10及20μmol/L核黄素光照处理后细胞周期主要阻滞于G2/M期;Westernblot结果显示凋亡相关基因p53、c-myc及Bax表达上调,而Bcl-2表达下调。结论:核黄素光化学反应抑制胃癌MGC80-3细胞生长的作用是以诱导细胞凋亡为主要途径,并与诱导细胞阻滞于G2/M期有关。BACKGROUND &OBJECTIVE: Photochemical riboflavin, the production of reactive oxygen species (ROS) , has been reported having cytotoxity on some cancer cells. The aim of this study was to investigate the effect of photochemical riboflavin on inducing apoptosis in human gastric cancer cell line MGC80 3. METHODS: Trypan blue exclusion method, Giemsa staining, DNA electrophoresis, DNA quantification, Western blot analysis, and flow cytometry were conducted to determine the effect of photochemical riboflavin on cell survival, morphology, DNA fragmentation, gene expression, and cell cycle arresting. RESULTS: The cell viability dropped down according to the riboflavin concentration and treating time. Exposure of the cells in 20 μmol/L riboflavin for 24 hours resulted in typical apoptotic morphology and G2/M arresting. As MGC80 3 cells were separately treated with 10, 20, 30, and 40 μmol/L photochemical riboflavin, DNA electrophoresis showed that the ladder bands, a typical feature of apoptotic cell, appeared in the groups treated by over 20 μmol/L photochemical riboflavin. The efficiency rates of DNA fragmentation were 35.4%, 54.1%, 70.6%, and 86.8%, respectively. Western blot analysis showed that the expression of apoptosis related proteins p53, C myc, and Bax were up regulated whereas the expression of Bcl 2 was down regulated. CONCLUSION: These results indicate that photochemical riboflavin has high efficiency of inducing cell apoptosis on MGC 80 3 cells in vitro and there is a correlation between apoptosis and G2/M arresting.

关 键 词：核黄素 光化学反应 细胞凋亡 胃癌细胞 

分 类 号：R735.2[医药卫生—肿瘤]