Li W, Zhou Y, Yang J, Zhang H H, Zhao S L, Zhang T, Huo J, Zheng P
Centeral Research Laboratory, the First People's Hospital of Lianyungang, Lianyungang 222001, China.
Zhonghua Zhong Liu Za Zhi. 2017 Jul 23;39(7):490-496. doi: 10.3760/cma.j.issn.0253-3766.2017.07.003.
To investigate the effect of curcumin on the apoptosis and autophagy of human gastric cancer cells with different degree of differentiation. Gastric cancer cell lines BGC-823 and MKN-28 were treated with curcumin at different concentrations. The effect of curcumin on cell proliferation was measured by MTT assay. Apoptosis was assessed by flow cytometry. Autophagy status was analyzed by acridine orange staining. The expression levels of apoptotic and autophagy-related proteins were detected by Western blot. The cell viability of BGC-823 and MKN-28 was inhibited by curcumin in a time- and dose-dependent manner. At 48 h after treatment, the IC(50) value of BGC-823 (15.18 μmol/L) was close to that of MKN-28 (15.84 μmol/L), and the difference was not statistically significant (=0.513). Meanwhile, flow cytometry showed that curcumin induced the apoptosis of gastric cancer cells in a dose-dependent manner. Western blot results showed that the expression of pro-apoptotic proteins bax, active-caspase-3 and active-caspase-9 was significantly increased in BGC-823 and MKN-28 cells, whereas that of the anti-apoptotic protein bcl-2 was strikingly reduced. In addition, the formation of acidic vesicular organelles in cytoplasm, conversion of LC3-Ⅰ to LC3-Ⅱ and increased levels of autophagy-related proteins Beclin1, Atg7 and Atg5-Atg12 were observed in curcumin-treated cells. Moreover, activation of PI3K/Akt/mTOR signaling pathway was also significantly suppressed after curcumin treatment. Blocking autophagy by adding the autophagy inhibitor 3-methyladenine (3-MA) significantly promoted the apoptotic cell death induced by curcumin. Curcumin induces apoptosis and protective autophagy in human gastric cancer cells . Curcumin combined with autophagy inhibitor may provide a more effective strategy for its clinical application.
研究姜黄素对不同分化程度人胃癌细胞凋亡和自噬的影响。用不同浓度的姜黄素处理胃癌细胞系BGC-823和MKN-28。采用MTT法检测姜黄素对细胞增殖的影响。通过流式细胞术评估细胞凋亡。用吖啶橙染色分析自噬状态。通过蛋白质免疫印迹法检测凋亡和自噬相关蛋白的表达水平。姜黄素以时间和剂量依赖性方式抑制BGC-823和MKN-28的细胞活力。处理48小时后，BGC-823的IC(50)值（15.18 μmol/L）接近MKN-28的IC(50)值（15.84 μmol/L），差异无统计学意义（=0.513）。同时，流式细胞术显示姜黄素以剂量依赖性方式诱导胃癌细胞凋亡。蛋白质免疫印迹结果显示，BGC-823和MKN-28细胞中促凋亡蛋白bax、活化的半胱天冬酶-3和活化的半胱天冬酶-9的表达显著增加，而抗凋亡蛋白bcl-2的表达显著降低。此外，在姜黄素处理的细胞中观察到细胞质中酸性囊泡细胞器的形成、LC3-Ⅰ向LC3-Ⅱ的转化以及自噬相关蛋白Beclin1、Atg7和Atg5-Atg12水平的升高。此外，姜黄素处理后PI3K/Akt/mTOR信号通路的激活也被显著抑制。添加自噬抑制剂3-甲基腺嘌呤（3-MA）阻断自噬可显著促进姜黄素诱导的凋亡性细胞死亡。姜黄素诱导人胃癌细胞凋亡和保护性自噬。姜黄素与自噬抑制剂联合使用可能为其临床应用提供更有效的策略。
