中文摘要：

目的观察活性维生素D[1,25-dihydroxyvitamin D3,1,25（OH）2D3]和卡铂（carboplatin,CBP）两种药物单独及联合作用对人肺癌A549细胞的抗肿瘤效应,并探讨其可能的作用机制。方法本研究分1,25（OH）2D3组,CBP组以及联合作用组。用CCK-8法测定细胞抑制率,使用激光扫描共聚焦显微镜进行维生素D受体（vitamin D receptor,VDR）的鉴定,用流式细胞仪进行细胞周期、细胞活性氧（reactiveoxidative species,ROS）及线粒体膜电位（mitochondrial membrane potential,MMP）的分析。结果 1,25（OH）2D3和CBP单独使用均可以抑制A549细胞的生长,且两者联合作用时具有协同作用,1,25（OH）2D3能显著提高CBP对A549细胞的抑制率。通过免疫荧光测得A549细胞中有较高维生素D受体的表达。细胞周期分析显示,经1,25（OH）2D3和CBP处理后的A549细胞,细胞周期发生变化,G0/G1期细胞数增多,S期和G2/M期细胞相应减少。两者联合作用后,以上趋势更加明显。与正常对照组相比较,各处理组均可使细胞ROS的释放增加（P〈0.05）,MMP下降（P〈0.05）,其中两种药物联合作用时细胞ROS的产生最多,MMP下降最为显著。结论 1,25（OH）2D3可以抑制A549细胞的增殖,并且与CBP联合作用时能显著增强其对肺癌细胞的杀伤能力。1,25（OH）2D3与CBP的协同作用与阻滞细胞周期的有序进行有关,并通过提高ROS和降低MMP抑制肺癌细胞的增殖。

英文摘要：

Objective To analyze vitamin D 1,25-dihydroxyvitamin D3（1,25（OH）2D3） and carboplatin（CBP） either drug alone and combined anti-tumor,effects on human lung cancer A549 cells,and to explore the possible mechanism of action.Methods The cells were divided to 1,25（OH）2D3 group,CBP group and combined treatment group.Cell viability was determined by CCK-8;expression of VDR was measured by immunofluorescence.The distributions of cell cycle,reactive oxidative species（ROS）and mitochondrial membrane potential（MMP）were analyzed by flow cytometry.Results Our results showed that although each of the drugs alone displayed antiproliferative activity,the growth inhibition of A549 cells was significantly enhanced in the combination group.Meanwhile,higher VDR expression was detected in A549 cells.Flow cytometry analysis indicated that the distribution of G0/G1 phase cells in combined group was remarkably increased,whereas,S phase and G2/M phase cells were significantly decreased.The trend is more evident in combination group.The content of ROS in combined group was significantly higher meanwhile MMP was lower than those in the alone drug group.Conclusion 1,25（OH）2D3 not only was able to suppress growth of A549 cells,but also enhance the anti-proliferative effect of CBP by inducing cell cycle arrest,increasing ROS and reducing MMP.