Effect of curcumin on radiosensitization of radioresistantnasopharyngeal carcinoma cell line CNE-2R and its mechanism / 中国药理学通报

ABSTRACT

Aim To investigate the effect of curcumin on radiosensitivity of radioresistant nasopharyngeal carcinoma cell line CNE-2R and its mechanism.Methods The concentration of curcumin was screened by MTT assay.Dose-survival curves were obtained according to the colony forming test for L-Q matching and multitarget-single hitting matching,while SF2 and the correlation parameters of radiation biology were calculated.The changes of cell cycle in CNE-2R cells caused by curcumin were also tested by flow cytometry(FCM).The differential expression of genes related to cell cycle and DNA damage repair were detected by RT-qPCR.Results CNE-2R cells could not be inhibited by 10 μmol·L-1 curcumin.Dealt with 10 μmol·L-1 curcumin for 24 h,the value of α/β increased to 1 596 from 6.56;the value of SF2 decreased to 0.361 Gy from 1.93 Gy;the value of N decreased to 1.06 from 1.60;the value of D0 decreased to 2.12 from 3.27;the value of Dq decreased to 0.12 from 1.53.FCM showed that the cells in G2 phase had a significant increase and the cells in S phase had a significant decrease after dealt with 10 μmol·L-1 curcumin for 24 h.The expression of CDK4 was significantly up-regulated and GADD45g,BRCA1 were significantly down-regulated.Conclusion Curcumin radiosensitizes nasopharyngeal carcinoma cell line CNE-2R by changing cell cycle and affecting DNA damage repair through regulating the expression of CDK4,GADD45 g and BRCA1.