Epigallocatechin-3-gallate Enhances Radiation Sensitivity in Colorectal Cancer Cells Through Nrf2 Activation and Autophagy
Epigallocatechin-3-gallate Enhances Radiation Sensitivity in Colorectal Cancer Cells Through Nrf2 Activation and Autophagy
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DOI：
10.21873/anticanres.12980
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发表时间：
2018-11-01
影响因子：
2
通讯作者：
Shimada, Mitsuo
中科院分区：
文献类型：
--
作者：
Enkhbat, Tumenjin;Nishi, Masaaki;Shimada, Mitsuo
背景/目的：表没食子儿茶素没食子酸酯（Epigallocatechin-3-gallate，EGCG）是绿色茶的主要多酚成分。表没食子儿茶素没食子酸酯在放射增敏癌细胞中起着潜在的作用。在结直肠癌细胞系中研究了表没食子酸没食子酸酯（表没食子酸没食子酸酯）和辐射的联合作用，重点关注核因子（红细胞衍生2）样2（Nrf 2）自噬信号传导。材料和方法：HCT-116细胞用12.5 μ M EGCG处理不同的时间段，2戈伊辐射，或两者兼而有之。用WST-8测定法测定细胞活力。用殖民地形成试验测定菌落数。采用实时定量聚合酶链反应分析LC 3和caspase-9的mRNA表达。结果：EGCG与放射线联合作用可明显抑制HCT-116细胞的生长。与对照组相比，菌落数减少至34.2%。免疫荧光显微镜图像显示，与对照组和单处理组相比，当细胞用EGCG和辐射的组合处理时，Nrf 2的核转位显著增加。辐射与EGCG联合处理可显著诱导LC 3和caspase-9 mRNA表达。结论：EGCG可通过抑制细胞增殖、诱导Nrf 2核转位和自噬来增加大肠癌细胞对辐射的敏感性。
Background/Aim: Epigallocatechin-3-gallate (EGCG) is a major polyphenolic component of green tea. EGCG plays a potential role in radio-sensitizing cancer cells. The combined effect of EGCG and radiation was investigated in a colorectal cancer cell line, focusing on nuclear factor (erythroid-derived 2)-like 2 (Nrf2) autophagy signalling. Materials and Methods: HCT-116 cells were treated with 12.5 ,uM EGCG for different periods of time, 2 Gy radiation, or both. Cell viability was determined with the WST-8 assay. The number of colonies was determined with the colony formation assay. mRNA expression of LC3 and caspase-9 was analyzed with quantitative real-time polymerase chain reaction. Results: Combination treatment with EGCG and radiation significantly decreased the growth of HCT-116 cells. The number of colonies was reduced to 34.2% compared to the control group. Immunofluorescence microscopy images showed that nuclear translocation of Nrf2 was significantly increased when cells were treated with the combination of EGCG and radiation compared to the control and single-treatment groups. Combined treatment with EGCG and radiation significantly induced LC3 and caspase-9 mRNA expression. Conclusion: EGCG increased the sensitivity of colorectal cancer cells to radiation by inhibiting cell proliferation and inducing Nrf2 nuclear translocation and autophagy.