摘要
目的:探讨血红素氧合酶-1(HO-1)对人肝癌SMMC-7721细胞5-氟尿嘧啶(5-FU)化疗敏感性的影响及其可能的机制。方法:应用不同浓度锌原卟啉(ZnPP)、氯化血红素(Hemin)单独或联合5-FU作用于人肝癌SMMC-7721细胞不同时间,MTT法观察药物对细胞生长抑制作用;蛋白质印迹法分析细胞HO-1蛋白表达变化;流式细胞术检测细胞凋亡率;Caspase-3活性检测试剂盒分析其凋亡机制。结果:ZnPP和5-FU均可明显抑制SMMC-7721细胞生长,呈剂量依赖性。5-FU联用ZnPP(20μmol/L)显著增加细胞生长抑制率和凋亡率,P=0.000;而联用Hemin(10μmol/L)显著降低细胞生长抑制率和凋亡率,P=0.000。SMMC-7721细胞中可见HO-1表达,应用Hemin和5-FU均能使其表达增强,联用ZnPP可逆转此现象。应用5-FU细胞内Caspase-3活性明显增高,约0.553±0.024,P=0.000;联用ZnPP后可进一步提高细胞内Caspase-3活性,达1.190±0.091,P=0.000。而联用Hemin后细胞内Caspase-3活性水平显著降低,约0.321±0.024,P=0.000。结论:阻断HO-1的表达可增强人肝癌SMMC-7721细胞对5-FU化疗敏感性,而诱导HO-1表达则降低人肝癌SMMC-7721细胞对5-FU化疗敏感性,这一作用机制可能与影响细胞Caspase-3活性有关。
OBJECTIVE：To study the potential effects of heme oxygenase-1 （HO-1） on the sensitivity of human liver cancer cell line SMMC-7721 to 5-FU in vitro and the possible mechanisms.METHODS：SMMC-7721 cells were treated with various concentrations of Hemin,ZnPP and 5-FU combination or alone for different time.Then the inhibition rates of cells were evaluated by the MTT assay.Western blot was used for the evaluation of the HO-1 expression.Flow cytometry was used to detect cellular apoptosis.The Caspase-3 activity was examined by the Caspase-3 colorimetric assay.RESULTS：The separate application of ZnPP and 5-FU significantly inhibited the proliferation of SMMC-7721 cells and the effect was dose-dependent.ZnPP （20 μmol/L） combined with 5-FU led to more significant inhibition rate and apoptosis of cells than ZnPP or 5-FU alone （P=0.000）.On the other Hand,Hemin （10 μmol/L） significantly increased the resistance of SMMC-7721 cells to 5-FU-mediated cytotoxicity （P=0.000）.5-FU or Hemin could increase the HO-1 protein expression compared with the control group,which could be reversed by the addition of ZnPP.The activity of Caspase-3 in the 5-FU group alone was significantly up-regulated to 0.553±0.024 （P=0.000）.The Caspase-3 activity in 5-FU plus ZnPP was re-elevated to 1.190±0.091,P=0.000,while Caspase-3 activity was significantly reduced to 0.321±0.024 at the presence of hemin after treatment with 5-FU （P=0.000）.CONCLUSIONS：The inhibition of HO-1 expression by ZnPP can enhance the chemosensitivity of SMMC-7721 cells to 5-FU in vitro.In contrast,the induction of HO-1 expression by hemin can decrease the cell sensitivity to 5-FU,which might be related to its action in up-（or down） regulation of the Caspase-3 expression.
出处
《中华肿瘤防治杂志》
CAS
2010年第15期1156-1159,共4页
Chinese Journal of Cancer Prevention and Treatment
基金
江苏卫生厅兴卫工程重点人才资助项目(RC2007058)
