罗格列酮5-Aza干预乳腺癌MCF-7 细胞系体外培养的效应*

目的:探讨过氧化物酶体增殖物激活受体γ（PPA Rγ）激动剂罗格列酮（罗格列酮）联合甲基转移酶抑制剂5- 脱氧氮杂胞苷（5-Aza-cdR）对雌激素受体阴性的人乳腺癌细胞株MCF-7 体外培养的抑制作用，为临床靶向治疗乳腺癌提供基础试验依据。方法:取对数生长期生长良好的乳腺癌MCF-7 细胞株，按2.0 × 10 6细胞/孔接种24孔板，按析因试验设置试验组。采用MTT 比色法观察罗格列酮和5- 氮胞苷对体外培养的MCF-7 细胞株生长的抑制作用；用倒置光学显微镜观察MCF-7 细胞用药前后的形态学变化；应用流式细胞仪检测细胞凋亡和细胞周期变化。结果:罗格列酮组、5- 氮杂胞苷组和联合组均能有效的抑制MCF-7 细胞生长（P<0.05）。 3 组的细胞抑制率随着时间的延长而增加。在72h 时点，罗格列酮组、5- 氮杂胞苷组、联合组和对照组的早期凋亡百分率分别为36.9% 、22.7% 、35.5% 、24.1% ，晚期凋亡百分率分别为16.0% 、43.7% 、37.7% 、40.2% ；3 组的G0、G1 期（DNA合成前期）细胞分别为81.3% 、67.3% 、74.5% 和6.0% ；S 期（DNA合成期）细胞分别为2.5% 、17.1% 、0 和38.5% 。G2 期（DNA合成后期）细胞分别为16.3% 、15.6% 、25.5% 和55.4% 。与对照组相比3 组G0、G1 期的阻滞作用均较强（P<0.05），联合用药未增强G0、G1 期的阻滞作用（P<0.05）。 结合分析细胞凋亡实验结果，联合用药既不增强周期阻滞效果未增强凋亡效果（P<0.05）。 结论:体外培养抑制试验证明罗格列酮、5-Aza均能有效的抑制乳腺癌细胞株MCF-7 的生长。罗格列酮对MCF-7 细胞株的干预作用是通过周期阻滞完成的，5-氮胞苷能干预细胞周期，其可能的机制是诱导细胞成熟分化。 

Rosiglitazone Combined with 5-Aza Interferes with Cell Cycle in MCF-7 Cells in Vitro

Objective: In order to gain basic experimental data for clinical targeted therapy of breast can -cer, we studied the inhibi ting effect of rosigl i tazone (the peroxisome prol i ferator-activated receptor γ activator) combined with 5-aza-2'-deoxycytidine (a demethylating agent inhibitor) on the MCF- 7 cell line in vitro.Methods: Fully-developed MCF- 7 cells were inoculated in 24-well tissue culture plates at 2.0 × 10 6 /L. MTT assay was used to observe the inhibiting effect of rosiglitazone and5-aza-2’-deoxycytidine on the growth of MCF- 7 cells. Changes in morphology were observed using inverted microscopy. We used flow cytometry (FCM) to ex -amine the apoptosis rate and percentage of cells in each stage of the cell cycle. Results: MTT assay results showed that the growth of MCF- 7 cells treated with rosiglitazone or 5-aza-2’-deoxycytidine or a combination of the two agents were effectively inhibited compared with the control group (P<0.05). The inhibitory rate was increased as time went by. At 72h after treatment, the apoptosis rates of cells in early cell cycle in the rosigli -tazone group, the 5-aza-2'-deoxycytidine group, the combination group and the control group were 36.9% , 22.7%,35.5% and 24.1%, respectively. The apoptosis rates of cells in late cell cycle in the four groups were 16%,43.7%,37.7% and 40.2%, respectively. The percentages of cells in G0 and G 1 phases combined in the rosiglitazone group, the 5-aza-2'-deoxycytidine group, the combination group and the control group were 81.3% ,67.3% ,74.5% and 6% , respectively. The percentages of cells in S phase in the above four groups were 2.5%,17.1%,0% and 38.5%, respectively. The percentages of cells in G2 phase were 16.3%,15.6%,?25.5% and 55.4% , respectively. Compared with cells in the control group, cells in G0 and G 1 phase were blocked by rosiglitazone,5-aza-2'-deoxycytidine or the combination of the two agents ( P<0.05). Combination of the two agents did not enhance the cell cycle blocking effect or the apoptosis rate ( P<0.05). Conclusion: Rosiglitazone and5-aza-2'-deoxycytidine can effectively inhibit the growth of human breast cancer cell line MCF-7. Rosiglitazone has a cell cycle blocking effect and 5-aza-2’-deoxycytidine interferes with cell cycle, possibly through induction of cell maturation and differentiation.