帕唑帕尼对甲状腺癌细胞和血管内皮细胞增殖的影响及其作用机制

目的 研究新型酪氨酸激酶抑制剂帕唑帕尼对甲状腺癌细胞株SW579和血管内皮细胞株HUVEC增殖的影响及作用机制.方法 将SW579和HUVEC暴露于不同浓度（1、2、4、8和16 μmoL/L）的帕唑帕尼至72 h,无药物处理的细胞作为对照.采用细胞活度测定、图像分析技术及分裂细胞荧光免疫染色观察评价帕唑帕尼对细胞增殖的影响,应用流式细胞仪进行细胞周期时相分析.结果 细胞活度测定显示,帕唑帕尼对SW579和HUVEC细胞的生长增殖均有明显的抑制作用,并呈浓度依赖性及时间依赖性,其半数抑制浓度（IC50）分别约为2和4μmol/L.图像分析显示,在IC50作用下,帕唑帕尼使两种细胞的细胞密度降低,分裂指数下降.帕唑帕尼作用48 h时,SW579细胞分裂指数（0.9％）明显低于其对照细胞（2.2％）,差异有统计学意义（P＜0.01）;HUVEC细胞分裂指数（1.9％）亦明显低于其对照细胞（4.0％）,差异有统计学意义（P＜0.01）.细胞周期时相分析表明,帕唑帕尼可使SW579和HUVEC发生细胞周期休止,分别休止于G1期和S期.帕唑帕尼作用24、48 h时,SW579在G1期的比例均明显高于其对照组细胞[（60.4±2.2）％比（49.2±1.6）％,（70.4±1.6）％比（58.6±3.3）％],差异有统计学意义（P＜0.01）;HUVEC细胞在S期的比例均明显高于其对照组细胞[（47.3±2.7）％比（39.5±0.6）％,（43.5±1.6）％比（28.8±4.2）％],差异有统计学意义（P＜0.01）.结论 帕唑帕尼对甲状腺癌细胞和血管内皮细胞的增殖均有明显的抑制效应,其作用是藉细胞周期休止作用而实现,但在两种细胞细胞周期休止时相不同.

Pazopanib inhibits the proliferations of thyroid cancer cells and vascular endothelial cells by cell cycle arrest

Objective To investigate the in vitro effects of pazopanib,a tyrosine kinase inhibitor,on the proliferations of both thyroid cancer cells and vascular endothelial cells and underlying mechanisms.Methods The cultured human anaplastic thyroid carcinoma cell line SW579 and human umbilical vein endothelial cell line HUVEC were exposed to pazopanib at different concentrations （1,2,4,8 and 16 μmol/L） for up to 72 hours,and the pazopanib-untreated cells were as control.The effects of pazopanib on the cell proliferations were assessed by cell viability assay,cell imaging analysis and mitosis index measure with immunofluorecent staining of mitosisi cells.Cell cycle analysis was performed by flow cytometry.Results Cell viability assay indicated that pazopanib inhibited the proliferations of both SW579 and HUVEC,in time-and dose-dependent manners,with the estimated IC50 of 2 μmol/L and 4 μmol/L,respectively.Cell imaging analysis showed that pazopanib at IC50 inhibited significantly the growths of SW579 and HUVEC,with significant decreased in the cell densities.Immunofluorecent staining for mitosis cells demonstrated that the mitosis index （0.9%） of the pazopanib-treated SW579 at 48 hours was lower significantly than that （2.2%） of control cells （P 〈 0.01）,and also the mitosis index （1.9%） of pazopanib-treated HUVEC at 48 hours was lower significantly than that of control cells （4.0%） （P 〈 0.01）.Flow cytometry demonstrated that pazopanib induced SW579 cells to arrest at G1 phase.At 24 hours and 48 hours,the percentages of pazopanib-treated SW579 in G1 phase were higher significantly than that of control group cells [（60.4 ± 2.2） % vs （49.2 ± 1.6） %,（70.4 ± 1.6） % vs （58.6 ± 3.3） %] （P 〈 0.01）,while the percentages of pazopanib-treated HUVEC in S phase were higher significantly than that of control group cells [（47.3 ± 2.7） % vs （39.5 ±0.6）%,（43.5 ±1.6）% vs （28.8 ±4.2）%] （P9〈0.01）.Conclusions Pazopanib inhibits the proliferations of both SW579 and HUVEC by inducing cell cycle arrest at different phases,leading G1 block of SW579 and S phase arrest of HUVEC respectively.Pazopanib is indicated as a new tyrosine kinase inhibitor to be used for the treatment of thyroid cancer by targeting both tumor cells and vascular endothelial cells related to tumor angiogenesis.