1,25-二羟维生素D_(3)对人结肠癌细胞凋亡和自噬的影响及机制研究

Study in effects of 1, 25-dihydroxyvitamin D_(3) on apoptosis and autophagy of colon cancer cells and its mechanism

目的观察1,25-二羟维生素D_(3)[1,25-(OH)_(2)D_(3)]对人结肠癌HCT-116细胞凋亡和自噬的影响并初步探讨其机制。方法体外培养人结肠癌细胞HCT-116,分成对照组、低剂量组、中剂量组、高剂量组和联合组[1,25-(OH)_(2)D_(3)高剂量联合腺苷单磷酸活化蛋白激酶(AMPK)抑制剂]共5组,观察并比较各组细胞凋亡和自噬情况。结果低剂量组、中剂量组、高剂量组的HCT-116细胞凋亡程度、自噬程度及cleaved Caspase3、cleaved Caspase8、LC3Ⅱ/LC3Ⅰ、Beclin-1、p-AMPK蛋白表达水平高于对照组,p-mTOR蛋白表达水平低于对照组,差异有统计学意义(P<0.05)。联合组的HCT-116细胞凋亡程度、自噬程度及cleaved Caspase3、cleaved Caspase8、LC3Ⅱ/LC3Ⅰ、Beclin-1、p-AMPK蛋白表达水平低于高剂量组,p-mTOR蛋白表达水平高于高剂量组,差异有统计学意义(P<0.05)。结论1,25-(OH)_(2)D_(3)可通过调控AMPK/mTOR信号通路增强结肠癌细胞凋亡和自噬,发挥抗肿瘤作用。

Objective To observe the effects of 1,25 dihydroxyvitamin D_(3)[1,25-(OH)_(2)D_(3)]on apoptosis and autophagy of human colon cancer HCT116 cells and explore its mechanism.Methods HCT-116 cells were cultured in vitro and divided into control group,low-dose group,medium-dose group,high-dose group and combined group[high-dose 1,25-(OH)_(2)D_(3) combined with adenosine monophosphate activated protein kinase(AMPK)inhibitor].Apoptosis and autophagy were observed and compared in each group.Results The degrees of apoptosis and autophagy,the expression levels of cleaved Caspase 3,cleaved Caspase 8,LC3Ⅱ/LC3Ⅰ,Beclin-1 and p-AMPK proteins in HCT-116 cells in low-dose group,medium-dose group and high-dose group were significantly higher,and the expression level of p-mTOR protein was significantly lower compared with those in the control group(P<0.05).The degrees of apoptosis and autophagy,the expression levels of cleaved Caspase 3,cleaved Caspase 8,LC3Ⅱ/LC3Ⅰ,Beclin-1 and p-AMPK proteins in HCT-116 cells in the combined group were significantly lower,while the expression level of p-mTOR protein was significantly higher compared with those in the high-dose group(P<0.05).Conclusion 1,25-(OH)_(2)D_(3) can enhance apoptosis and autophagy of colon cancer cells by regulating AMPK/mTOR signaling pathway thereby playing anti-tumor roles.