EGCG联合不同剂量放疗对人肝癌细胞系HepG2中hTERT表达的影响  

EGCG in combination with radiotherapy down-regulates hTERT expression in HepG2 cells

作　　者：刘礼[1] 谢纪文 王熙[1] 谢烨明[2] 

机构地区：[1]湖北省武汉市协和医院中西医结合科,湖北省武汉市430022 [2]武汉工业学院生物与制药学院,湖北省武汉市430023

出　　处：《世界华人消化杂志》2010年第18期1873-1878,共6页World Chinese Journal of Digestology

基　　金：湖北省卫生厅中医药;中西医结合科研课题基金资助项目;No.200389~~

摘　　要：目的:研究相同剂量表没食子儿茶素没食子酸酯(EGCG)联合不同剂量放疗对HepG2中hTERT基因表达的影响,探讨EGCG成为放疗增敏剂的作用.方法:用MTT比色法检测EGCG对HepG2细胞增殖的影响,用荧光显微镜检测EGCG诱导HepG2的细胞凋亡,从而找到合适的EGCG(25μmol/L)剂量用于观察其放射效果的实验;采用实时荧光定量PCR检测不同剂量放疗(0、2、4、6Gy)联合EGCG和不联合EGCG治疗后,HepG2中hTERT基因的表达.放疗用直线加速器6MVX线.结果:EGCG具有抑制HepG2细胞增殖并诱导HepG2细胞凋亡的作用.同时,不同剂量放疗联合EGCG和不联合EGCG治疗后HepG2中hTERT基因的表达比较,空白组无显著差异;2Gy组、4Gy组、6Gy组均有显著差异(hTERT基因表达的扩增倍数:0.477±0.025vs0.973±0.024;1.110±0.083vs1.382±0.051;1.174±0.128vs1.452±0.109,P<0.01或0.05),并以2Gy组最为显著.结论:EGCG具有抑制HepG2细胞增殖并诱导其凋亡的作用;EGCG联合不同剂量放疗可能下调HepG2中hTERT基因水平,从而抑制端粒酶活性,以放射剂量为2Gy时显著,因此,EGCG有可能成为放疗增敏剂.AIM：To study the effect of （-）-epigallocatechin-3-gallate （EGCG） in combination with radiotherapy （different doses） on the expression of hTERT in HepG2 cells and to explore the possibility of using EGCG as a radiation sensitizer.METHODS：To find an optimal EGCG dose used in subsequent experiments, the effect of different concentrations of EGCG on the proliferation and apoptosis of HepG2 cells was detected by MTT assay and fluorescence microscopy.After HepG2 cells were treated with EGCG （25 μmol/L） in combination with different doses of radiotherapy （2, 4 and 6 Gy, respectively）, the expression of hTERT in HepG2 cells was detected by real-time fluorescent quantitative PCR.RESULTS：EGCG could inhibit proliferation and induce apoptosis in HepG2 cells.Treatment of HepG2 cells with EGCG in combination with different doses of radiotherapy （2, 4 and 6 Gy, respectively） significantly down-regulated hTERT expression when compared with those treated with EGCG alone （0.477±0.025 vs 0.973±0.024, 1.110±0.083 vs 1.382±0.051, 1.174±0.128 vs 1.452±0.109; all P0.01 or 0.05）, particularly prominent in cells undergoing radiotherapy at a dose of 2 GY.CONCLUSION：EGCG can inhibit proliferation and induce apoptosis in HepG2 cells.EGCG in combination with different doses of radio-therapy can down-regulate hTERT expression in HepG2 cells and thus inhibit telomerase activity.EGCG may be a potential radiation sensitizer.

关 键 词：表没食子儿茶素没食子酸酯 人端粒酶逆转录酶 HepG2 放疗增敏 

分 类 号：R735.7[医药卫生—肿瘤]