目的:探究左卡尼汀对多西他赛抑制肺癌细胞NCI-H520增殖的影响,并初步探索其机制.方法:实验将NCI-H520细胞分为阴性对照组,左卡尼汀组,多西他赛组以及联合用药组.四甲基偶氮唑蓝(MTT)法检测细胞增殖情况,流式细胞仪检测细胞凋亡和细胞周期,蛋白质免疫印迹法检测目标蛋白P21,P53,BAX和BCL-2的表达情况.结果:与不同单药组(左卡尼汀组和多西他赛组)相比,联合用药组对细胞增殖的抑制作用均增强,细胞增殖率分别由(95.5±3.97)％和(65.73±2.22)％下降到(54.4±1.67)％,P＜0.01,镜下细胞密度下降.联合用药使G1/G0期细胞分别由(67.21±6.0)％和(11.52±0.89)％下降到(3.98±0.42)％,P＜0.05.G2/M期细胞分别由(11.84±5.05)％和(54.91±2.38)％上升到(64.56±0.9)％,P＜0.05.周期相关蛋白P21,P53的表达量增加,且差异均具有统计学意义.所有实验组之间的细胞凋亡率和凋亡相关蛋白BAX,BCL-2的表达量没有明显差异.结论:24 h时,联合用药组中,左卡尼汀可能通过上调P21,P53的蛋白表达来增强细胞的G2/M期阻滞,进而增强多西他赛对NCI-H520细胞增殖的抑制作用.

OBJECTIVE L-CNT has certain effects in improving the cardiac toxicity and peripheral nerve toxicity aspects caused by chemotherapy drugs.This study aimed to investigate the proliferation and cell apoptosis effects of combination treatment L-CNT and DTX on NSCLC GLC-82 cells,and to explore its mechanism.METHODS GLC-82 cells were treated with different concentrations of L-CNT(0.625,1.25,2.5,5,10,20,40,80 μg/mL) and DTX(0.01,0.1,1,5,10,20,40,80 μg/mL) in vitro.The inhibitory rates of cells were measured by MTT assay.Morphological changes were observed with inverted microscope.GLC-82 cells were treated with the combination treatment of L-CNT (1.25,20,80 μg/mL) and DTX(9.301 μg/mL) for 24 h,and then the proliferation inhibitory rates were detected by MTT assay.The cell apoptosis was analyzed by Annexin Ⅴ-FITC/PI double staining.Western blot was used to analyzed the expression of Bcl-2,Bax and adenine nucleotide translocator1 (ANT1).RESULTS After 24 h and 48 h,compared with the control group,the proliferation rates of L-CNT (1.25,20,80 μg/mL) were (14.52 ± 0.73)％,(27.03 ±1.21)％,(19.77±0.65)％,F=42.538,P=0.001 and (11.37±0.13)％,(19.56±1.01)％,(14.89±0.51)％,F=52.119,P=0.001,respectively.Compared with DTX(27.319 μg/mL),the cell proliferation rate of L-CNT(1.25,20,80 μg/mL) and DTX combined group increased from(49.49 ± 2.52) ％ to (52.64± 2.43) ％,(59.44 ±-3.20) ％ and (53.15±2.37) ％,F=7.412,P=0.011.Compared with the DTX(9.301 μg/mL)group,cell density of the combination group was increased,Flow cytometry showed that the apoptosis rates were reduced to (21.90±1.98)％,(14.38 ± 2.35) ％ and (22.42± 1.43) ％ from (24.67±1.95) ％,F=15.697,P =0.001.The combination group could increase the expression of Bcl-2 and decrease the expression of Bax,at the same time,the expression of ANT1 was also decreased.CONCLUSIONS Treatment with L-CNT and DTX has impacts on the proliferation of GLC-82 cells.The possible mechanism of action is achieved by regulating the expression of Bcl-2 protein family and regulating the opening and closing of mitochondrial membrane permeability transition pore.

目的 探讨左卡尼汀对氟尿嘧啶(5-fluorouracil,5-Fu)抑制人胃腺癌MGC803细胞增殖作用的影响.方法 将MGC803细胞分为阴性对照组、5-Fu组、左卡尼汀和5-Fu联合用药组(左卡尼汀+/→5-Fu)进行实验.四甲基偶氮唑蓝(MTT)法检测细胞的增殖,流式细胞术检测细胞凋亡和细胞周期,蛋白质印迹法检测Bcl-2、Bax、ANT1和cleaved-PARP蛋白的表达.结果 与5-Fu-单药组相比,左卡尼汀和5-Fu联合用药组抑制MGC803细胞增殖的作用增强,细胞凋亡百分率增大,细胞周期S期阻滞,上调Bax、ANT1和cleaved-PARP蛋白的表达,下调Bcl-2蛋白的表达.实验结果还显示,左卡尼汀和5-Fu联合应用时,给药方法可以影响5-Fu对MGC803细胞的抑制作用.与左卡尼汀+5-Fu组相比,左卡尼汀→.5-Fu组细胞凋亡百分率由(19.60±1.06)％增加至(24.17±3.12)％(P＜0.05),Go/G1期细胞比例由(72.95±0.91)％降低至(62.62±1.04)％,S期细胞比例由(27.05±0.91)％增加至(37.35±1.03)％(P＜0.001).结论 左卡尼汀可能通过影响Bcl-2家族蛋白的表达和细胞周期,增强5-Fu对MGC803细胞增殖的抑制作用.