三氧化二砷对膀胱癌T24细胞生长和裸鼠移植瘤的抑制作用及其机制

Inhibitory effects of As2O3 on growth of bladder cancer T24 cells and ectopic tumor growth of nude mice

目的 探讨三氧化二砷（As2O3）对膀胱癌T24细胞生长和裸鼠移植瘤的抑制作用及其机制.方法 应用细胞计数试剂盒（CCK-8）检测不同剂量As2O3（1、5、10 μmol/L）和5-氟尿嘧啶（5-Fu,4 μmol/L）对膀胱癌T24细胞生长的体外抑制作用;反转录-聚合酶链反应（RT-PCR）和Western blot检测不同剂量As2O3（1、5、10μmol/L）和5-Fu（4μmol/L）作用后膀胱癌T24细胞细胞周期素（Cyclin） D1、p2l、B细胞淋巴瘤/白血病-2（bcl-2）、B细胞淋巴瘤/白血病-2相关X蛋白（bax）表达;观察不同剂量As2O3对[10、20、30 mg/（kg·d）]和5-Fu[20.0 mg/（kg·d）]对T24细胞裸鼠移植瘤生长的体内抑制作用.结果 膀胱癌T24细胞给药48 h后,As2O3低（1μmol/L）、中（5μmol/L）、高（10 μmol/L）剂量组和5-Fu（4μmol/L）细胞抑制率分别为36.53％、67.44％、79.60％和80.90％.荷瘤裸鼠治疗实验以生理盐水组为对照,5-Fu,As2O3低、中、高剂量组的体内抑瘤率分别为54.5％、29.4％、38.8％、52.1％,说明As2O3对裸鼠T24细胞移植瘤的生长有抑制作用.RT-PCR及Western blot结果发现药物作用24 h后,不同剂量（1、5、10 μmol/L）As2 O3均明显降低Cyclin D1和bcl-2表达,p21水平未发生变化,bax表达明显上调.结论 As2O3能明显抑制膀胱癌T24细胞的增殖和裸鼠移植瘤的生长,其作用机制可能与影响细胞周期以及诱导细胞凋亡有关,其中涉及多种基因的调控.

Objective To study the effect of arsenic trioxide （As2 O3） on growth of human bladder cancer T24 cells and ectopic tumor growth of nude mice,as well as the related mechanism.Methods The cells were exposed to different concentrations （1,5,10 μmol/L） of As2O3 and 5-fluorouracil （5-Fu,4 μmol/L）.The cytotoxic effects of As2O3 on cells were measured from 24 h to 48 h by cell counting kit-8 （CCK-8） assay.The expression of cyclin D1,p21,B cell lymphoma/leukemia-2 （bcl-2）,bcl-2 associated X protein （bax） was evaluated using reverse transcriptase-polymerase chain reaction （RT-PCR） and Western blotting.In the experiment in vivo,the average tumor size and tumor inhibition rate were calculated in tumor bearing mice treated with As2O3 （10,20,30 mg/kg · day） as well as 5-Fu （20.0 mg/kg · day）.Results The cell inhibition rate of T24 cells was 36.53%,67.44%,79.60%,and 80.9% after treatment with As2O3 （1,5,10 μmol/L） and 5-Fu （4 μmol/L） after 48 h respectively.In vivo,the tumor inhibition rate was 29.4%,38.8%,52.1%,and 54.5% after treatment with As2O3 （1,5,10 μmol/L） and 5-Fu respectively.After treatment for 24 h,As2O3 down-regulated the expression of cyclin D1 and bcl-2,and up-regulated the expression of bax,but had no significant effect on the p21 expression.Conclusion The As2O3 has a significant anti-tumor effect on the human bladder cancer T24 cells and bladder carcinoma in nude mice,which may be related to the induction of the apoptosis of carcinoma cells and regulation of cell cycle,involving in several genes regulation.