大黄素对膀胱癌细胞BIU87增殖和凋亡的影响

Effects of emodin on proliferation cycle and apoptosis of human bladder cancer cell line BIU87

目的探讨大黄素对人膀胱癌细胞BIU87生长的抑制作用及其对细胞增殖周期和凋亡的影响。方法采用甲基噻唑（MTT）比色法测定不同浓度大黄素在不同作用时间内对在体外培养BIU87细胞增殖的影响，同时应用流式细胞仪检测细胞增殖周期的变化，免疫组化SP法检测细胞内bcl-2和caspase-3蛋白的表达水平。结果在一定范围内，大黄素的浓度（10—80μg/ml）越高、作用时间越长，对肿瘤细胞生长的抑制作用越强，凋亡率也越高[分别为（9．84±21．13）％、（18．32±22．14）％、（29．73±1．42）％、（42．13±2．36）％]，与对照组[（2．01±20．92）％]相比，差异均有统计学意义（F=531．85，P〈0．01）；大黄素可在G0／G1期阻滞人膀胱癌细胞BIU87的增殖，使S期细胞比率降低[分别为（33．27±1．26）％、（29．17±1．39）％、（16．94±0．86）％、（10．85±1．47）％]，与对照组[（35．45±0．38）％]相比，差异均有统计学意义（F=524．64，P〈0．01）。大黄素作用48h后，BIU87细胞中bel-2蛋白表达下降（灰度值分别为122．65±2．12、131．37±1．62、134．81±1．36、145．55±2．01），easpase-3蛋白表达上调（灰度值分别为135．26±1．41、130．22±1．74、126．11±1．77、118．36±1．53），呈浓度依赖性，与对照组（灰度值分别为108．42±3．73、149．35±1．82）相比，差异均有统计学意义（F=216．23、224．83，P〈0．01）。结论大黄素在体外能抑制人膀胱癌细胞株BIU87的生长、诱导细胞凋亡，其作用与下调bcl-2蛋白表达、上调easpase一3蛋白表达和阻滞细胞周期于Go／G．期有关。

Objective To study the suppressive role of emodin on the growth and its effect on the proliferation cycle and apoptosis of human bladder cancer cell line BIU87. Methods The effect of different concentration of emodin at different time point on cell proliferation of BIU87 were measured with methylthia zole （MTT） chromatometry, the cell proliferation cycle were detected with flow cytometry, expressions of bel-2 and caspase-3 were detected by SP of immunohistochemistry. Results Within a certain range, the higher concentration of emodin （10 -80 μg/ml） and the longer action time are positive related the more significant inhibition of tumor cell growth and the higher apoptosis rate [ （9. 84 ± 1.13 ）%, （18.32 ± 2. 14） %, （29. 73 ± 1.42） %, （42. 13 ± 2. 36 ） %, respectively ]. Compared with control group [ （ 2.01 ± 0. 92 ）% ], the differences were statistically significant（ F = 531.85, P 〈 0. 01 ）. Emodin could inhibit the proliferation of human bladder cancer cell BIU87 by blocking BIU87 cell in G0/Gl stage, thus cut down cell proportion in stage of S [ （33.27 ± 1.26） %, （ 29. 17 ± 1.39 ） %, （ 16. 94 ± 0. 86 ） %, （ 10. 85_± 1.47 ） %, respectively ], compared with the control group [ （ 35.45± 0. 38 ） % ], the differences were statistically sig- nificant （ F = 524.64, P 〈 0. 01 ）. After 48 h of emodin treatment, the bcl-2 expression（ Grayscale values： 122. 65± 2. 12,131.37 ± 1.62,134. 81 ± 1.36,145.55 ± 2. 01, respectively） was decreased and the easpase-3 expression （ Grayscaie values ： 135.26 ± 1.41,130. 22 ± 1.74,126. 11 ±1.77,118.36± 1.53, res-pectively） was increased in a dose dependent manner. Compared with control group （Grayscale values： 108.42 ± 3.73,149.35 ± 1.82, respectively）, the differences were statistically significant （ F = 216. 23, 224. 83, P 〈 0. 01 ）. Conclusions Emodin could significantly inhibit the growth and induce apoptosis of BIU87 ceils in vitro, which may be through down regulation of bcl-2, and up regulation of caspase-3, and blocking BIU87 cell in G0/G1 stage.