苦参碱对人肺腺癌细胞株A549生长抑制和c-myc、hTERT蛋白表达的影响

背景与目的 近年研究发现,端粒酶与人类肿瘤的发生、发展密切相关,并成为肿瘤治疗的共同作用靶点.苦参碱抗肺癌的研究报道对其体外生长抑制作用发生的可能的机制尚未阐明,本研究的目的是探讨苦参碱对肺癌A549细胞生长影响及与端粒酶相关的机制.方法 MTT法测定苦参碱对A549细胞增殖抑制作用,Hoechst33342-PI荧光双染法观察细胞凋亡,流式细胞仪检测细胞周期和细胞凋亡率,免疫细胞化学(SP法)测定c-myc、hTERT蛋白表达的变化.结果 苦参碱可明显抑制A549细胞的增殖(P<0.05),呈一定的时间剂最效应关系;荧光显微镜下看到凋亡细胞核染色质凝聚成团,核碎裂形成凋亡小体;流式细胞术分析:C0/C1期细胞比例呈增高趋势,S期细胞比例呈降低趋势,且凋亡率不断增加;处理组细胞c-myc、hTERT蛋白表达减少(P<0.05),c-myc的AOD值与hTERT的AOD值呈正相关(r=0.633,P<0.01).结论 苦参碱对A549细胞生长抑制作用可能与下调c-myc、hTERT的蛋白表达有关.

Effects of matrine on the growth inhibition, c-myc and hTERT protein expression in human adenocarcinoma lung cancer cell line A549

Background and objective It was reported that telomerase was associated with the oncogenesis and progression of cancer, and to be the common targets of cancer therapy. The mechanism of matrine on lung cancer in vitro is not clear. We studied the effect of matrine on growth of human lung adenocarcinoma A549 cells and the mechanism related with telomerase. Methods MTT was used for measuring A549 cells viability, Hoechst 33342-propidium iodide fluorescent staining for observing apoptotic cells, flow cytometry (FCM) for analyzing cell cycle and apoptosis, and immunocytochemistry for measuring the protein expressions of c-myc and hTERT in A549 cells. Results Matrine inhibited the proliferation of A549 cells with a time-dose-dependent manner (P<0.05). Hoechst 33342-propidium iodide staining showed apoptotic cells with chromatin condensation and fragmentation of nuclei. FCM analysis indicated elevating rate of cells in G0/G1 phase, lowering rate of that in S phase and the highering apoptotic rate. The levels of c-myc and hTERT protein expression in the matrine group was lower than that in the control group (P<0.05), and AOD of c-myc showed positive correlation with AOD of hTERT (r=0.633, P<0.01) Conclusion The inhibitory effect of matrine on A549 cells may be related to the lower expression of c-myc and hTERT.