RT Journal Article
SR Electronic
T1 Epigallocatechin-3-gallate Enhances Radiation Sensitivity in Colorectal Cancer Cells Through Nrf2 Activation and Autophagy
JF Anticancer Research
JO Anticancer Res
FD International Institute of Anticancer Research
SP 6247
OP 6252
DO 10.21873/anticanres.12980
VO 38
IS 11
A1 TUMENJIN ENKHBAT
A1 MASAAKI NISHI
A1 KOZO YOSHIKAWA
A1 HIGASHIJIMA JUN
A1 TAKUYA TOKUNAGA
A1 CHIE TAKASU
A1 HIDEYA KASHIHARA
A1 DAICHI ISHIKAWA
A1 MASAHIDE TOMINAGA
A1 MITSUO SHIMADA
YR 2018
UL http://ar.iiarjournals.org/content/38/11/6247.abstract
AB 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 μM 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.