mDRA-6与尼美舒利对人肝癌细胞系SMMC-7721细胞的协同杀伤效应

Synergistic Lethal Effect of mDRA-6 and Nimesulide on Human Hepatocellular Cancer Cell Line SMMC-7721

背景与目的:mDRA-6为本实验室制备的具有肿瘤细胞杀伤作用的抗人死亡受体5(death receptor5,DR5)的单克隆抗体,尼美舒利作为特异性环氧合酶-2(cyclooxygenase-2,COX-2)抑制剂,近年来发现其对某些肿瘤细胞系的细胞具有促凋亡作用,本研究探讨mDRA-6与尼美舒利对肝癌细胞系SMMC-7721的杀伤作用,及二者有无协同效应。方法:流式细胞术检测细胞表面DR5的表达率;分别用一定浓度的mDRA-6、尼美舒利、mDRA-6联合200μmol/L尼美舒利处理SMMC-7721细胞,MTT法检测细胞毒性作用,Hoechst33258染色观察SMMC-7721细胞核形态变化,流式细胞术定量分析凋亡细胞率。结果:SMMC-7721细胞表面DR5的表达率为95.0%,mDRA-6能够诱导SMMC-7721细胞凋亡,存在浓度依赖性(r=0.984,P=0.002),25ng/mL作用12h可杀伤10.5%的细胞,1600ng/mL作用12h可杀伤35.0%的细胞。尼美舒利能够诱导SMMC-7721细胞凋亡,200μmol/L作用12h可使5.0%的细胞凋亡,800μmol/L作用12h可杀伤34.0%的细胞,存在浓度依赖性(r=0.929,P=0.002)。尼美舒利与mDRA-6联合对SMMC-7721细胞具有协同杀伤作用(q=1.23),200μmol/L的尼美舒利协同25ng/mL与1600ng/mL的mDRA-6作用12h可分别杀伤31.2%与91.1%的SMMC-7721细胞,Hoechst33258染色和Annexin V/PI染色证实杀伤作用是通过诱导细胞凋亡实现的。结论:mDRA-6与尼美舒利均有杀伤SMMC-7721细胞的作用,二者具有协同作用,该作用是通过诱导凋亡实现的。

BACKGROUND ＆ OBJECTIVE, Both mDRA-6, a monoclonal antibody of death receptor 5 （DR5） in human cells prepared by our key laboratory, and nimesulide, a specific cyclooxygenase-2 （COX-2） inhibitor, can induce apoptosis of some malignant tumor cells. This study was to investigate the lethal effects of mDRA-6 and nimesulide on human hepatocellular cancer cell line SMMC-7721, and explore the possible mechanism. METHODS： The expression of DR5 on SMMC-7721 cells was detected by flow cytometry （FCM）. SMMC-7721 cells were treated with mDRA-6 and nimesulide alone or in combination. Cell morphology was observed under microscope with Hoechst33258 staining. Cytotoxicity was examined by MTT assay. Cell apoptosis was detected by FCM. RESULTS. The positive rate of DR5 on SMMC-7721 cells was 95.0%. The apoptosis of SMMC-7721 cells could be induced by both mDRA-6 and nimesulide： the apoptosis rates were 10.5% when treated with 25 ng/mL mDRA-6 for 12 h, 35.0% when treated with 1 600 ng/mL mDRA-6, 5.0% when treated with 200 μmol/L nimesulide, and 34.0% when treated with 800 μol/L nimesulide. The combination of mDRA-6 and nimesulide exhibited synergistic effect on the apoptosis of SMMC-7721 cells （q=1.23）： the apoptosis rates were 31.2% when treated with 200 iJmol/L nimesulide and 25 ng/mL mDRA-6 for 12 h, and 91.1% when treated with 200 iJmol/L nimesulide and 1 600 ng/mL mDRA-6 for 12 h. CONCLUSIONS. Both mDRA-6 and nimesulide can induce the apoptosis of SMMC-7721 cells. The combination of mDRA-6 and nimesulide exhibits synergistic lethal effect on SMMC-7721 cells.