摘要
目的:观察表没食子儿茶素没食子酸酯(Epigallocatechin-3-gallate,EGCG)对人胃癌SGC7901细胞裸鼠移植瘤生长的抑制作用,探讨EGCG诱导移植瘤细胞凋亡作用的分子机制。方法:建立人胃腺癌(SGC7901)细胞裸鼠异种移植瘤模型,用不同剂量的EGCG进行治疗,并设对照;采用TUNEL法检测肿瘤组织中细胞凋亡情况,Western blot法检测肿瘤组织凋亡相关基因NF-κB(p65)、Bcl-2、Bax、Caspase-3蛋白表达情况。结果:EGCG对移植瘤生长有明显抑制作用;TUNEL法发现EGCG导致移植瘤内细胞发生凋亡;Western blot分析表明EGCG能下调NF-κB(p65)蛋白的表达,促使Bax/Bcl-2蛋白表达的比值增高,并且可以促进Caspase-3的活化。结论:EGCG对人胃癌细胞裸鼠移植瘤有明显的抑制作用,并能诱导移植瘤细胞凋亡。其机制可能与通过NF-κB(p65)的下调,促使Bax/Bcl-2比值增高,进而导致Caspase-3的活化而诱导细胞发生凋亡相关。
Objective：To study the inhibitory effect of EGCG on human gastric carcinoma cells in nude mice xenografts and to investigate the molecular mechanism of the apoptotic cell induced by EGCG. Methods： Human gastric carcinoma cells were planted into nude mice to establish the cancer model . The xenograft tumor growth in nude mice was observed after treated with intraperitoneal injection of EGCG at different dosages . TUNEL staining method was used to detect the apoptosis of implanted tumor cells . Expression of NF- κB（p65） ,Bcl -2 ,Bax,Caspase-3 in every group xenograft tumor were determined by Western Blot analysis. Results： EGCG significantly inhibited tumor growth after being injecting intraperitoneally in the nude mice. The apoptotic ceils in implanted tumor induced by EGCG were detected by TUNEL staining. Western Blot analysis showed that the expression level of NF - κB （p65） was down - regulated by EGCG ; the ratio of Bax protein and Bcl - 2 protein in xenograft tumor was adding as increasing the concentration of EGCG ; EGCG may accelerate the activation of procaspase - 3. Conclusion： EGCG could significantly inhibit tumor growth in xenograft nude mice with human gastric carcinoma cells through inducing apoptosis. This action may be mediated by down - regulation of NF - κB （ p65 ） expression , up - regulation of Bax and Bcl- 2 , and resulting in Caspase -3 activation.
出处
《现代肿瘤医学》
CAS
2008年第4期530-534,共5页
Journal of Modern Oncology
