目的探讨姜黄素(curcumin)对乳腺癌细胞中顺铂(Cisplatin,CDDP)治疗敏感性的影响及其可能机制。方法 CCK-8检测、Hoechst染色观察CDDP、姜黄素单独及联合用药48 h对MCF7细胞增殖抑制和细胞凋亡的影响;Western blot分析MCF7细胞在CDDP(0、1.25、2.5、5、10、20μg/m L)、姜黄素(0、1、5、20、30、50、100μmol/L)单独及联合处理后FEN1(flap endonuclease 1)表达水平的变化;CCK-8检测沉默FEN1对MCF7细胞中CDDP敏感性的影响。结果 CDDP、姜黄素均可以剂量依赖方式抑制MCF7细胞增殖,其IC50分别为5、30μmol/L;与单独2μg/m L CDDP处理组比较,2μg/m L CDDP联合20μmol/L姜黄素、30μmol/L姜黄素处理组对细胞增殖的抑制效应明显增强[分别为(84.1±0.8)%、(51.1±0.5)%、(29.4±0.3)%,P〈0.05];与单独20μmol/L姜黄素处理组比较,20μmol/L姜黄素联合2μg/m L CDDP、5μg/m L CDDP处理组对细胞增殖的抑制效应也明显增强[分别为(76.9±0.7)%、(42.4±0.3)%、(31.6±0.4)%,P〈0.05];2μg/m L CDDP联合20μmol/L姜黄素组的细胞凋亡明显增强(P〈0.05);与Control siRNA组比较,FEN1 siRNA+CDDP组可显著增强CDDP抑制MCF7细胞增殖的敏感性[(25.4±0.3)%vs(18.7±0.2)%,P〈0.05];CDDP增殖抑制无效浓度或低浓度时,FEN1蛋白的表达随CDDP的处理剂量依赖性上调,而姜黄素可剂量依赖性下调FEN1蛋白表达;与单独CDDP和姜黄素处理组比较,2μg/m L CDDP联合20μmol/L姜黄素组可显著降低FEN1蛋白表达(P〈0.05)。结论姜黄素可增强CDDP对乳腺癌细胞的敏感性,其机制与降低细胞FEN1的表达有关。
Objective To explore the effect of curcumin on the sensitivity of breast cancer cells to cisplatin( CDDP) and possible mechanism. Methods CCK-8 assay and Hoechst staining were used to observe the proliferation and apoptosis of MCF-7 cells treated with curcumin alone or in combination with CDDP for 48 h. Western blotting was used to detect the expression level of flap endonuclease 1( FEN1) in MCF7 cells treated as above. The sensitivity of FEN1-silenced MCF-7 cells to CDDP was detected by CCK-8assay. Results Both CDDP and curcumin could inhibit MCF-7 cell proliferation in a dose-dependent manner,and the IC50 values of CDDP and curcumin were 5 and 30 μmol / L,respectively. Compared with the cells treated with 2 μg / m L CDDP alone,the proliferation of the cells treated with CDDP in combination with20 or 30 μmol / L curcumin was significantly inhibited [( 84. 1 ± 0. 8) % vs( 51. 1 ± 0. 5) %,( 84. 1 ± 0. 8) %vs( 29. 4 ± 0. 3) %,respectively,P〈 0. 05]. Compared with the cells treated with curcumin alone,the proliferation of the cells treated with 20 μmol / L curcumin in combination with 2 or 5 μg / m L CDDP was also significantly inhibited [( 76. 9 ± 0. 7) % vs( 542. 4 ± 0. 3) %,( 76. 9 ± 0. 7) % vs( 31. 6 ± 0. 4) %,respectively,P〈 0. 05]. Apoptosis of the cells treated with 2 μg / m L CDDP in combination with 20 μmol / L curcumin was obviously increased( P〈 0. 05). Compared with control treatment,silencing FEN1 with siRNA could enhance the sensitivity of MCF7 cell to CDDP( P〈 0. 05). FEN1 protein was up-regulated in a dosedependent manner in the cells treated with low concentration or invalid concentration of CDDP. However,curcumin could obviously down-regulate FEN1 protein in a dose-dependent manner. Compared with the cells treated with CDDP or curcumin alone,FEN1 protein expression was significantly reduced in the cells treated with 2 μg / m L CDDP in combination with 20 μmol / L curcumin( P〈 0. 05). Conclusion Curcumin can enhance the s