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EGCG in combination with radiotherapy down-regulates hTERT expression in HepG2 cells
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- Author:
- No author available
- Journal Title:
- WORLD CHINESE JOURNAL OF DIGESTOLOGY
- Issue:
- 18
- DOI:
- 10.3969/j.issn.1009-3079.2010.18.005
- Key Word:
- 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
Abstract： 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、6 Gy)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、4 Gy组、6 Gy组均有显著差异(hTERT基因表达的扩增倍数: 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, P <0.01或0.05), 并以2 Gy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2 Gy时显著, 因此,EGCG有可能成为放疗增敏剂.
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