PI3K特异性抑制剂LY294002对卵巢癌紫杉醇耐药细胞株逆转作用的研究

Reversal Effect of Phosphatidylinositol 3'-kinase Inhibitor LY294002 during Chemotherapy on Paclitaxel Resistance of Ovarian Cancer Cell Lines

目的:研究磷脂酰肌醇-3-激酶(P13K)特异性抑制剂LY294002对卵巢癌紫杉醇耐药细胞株(A2780/Taxo1)多药耐药逆转的影响。方法:将P13K特异性抑制剂LY294002处理卵巢癌紫杉醇耐药细胞24 h后,用CCK-8(Cell CountingKit-8)法检测细胞的增殖速度、对紫杉醇敏感性的分析;采用流式细胞技术检测细胞周期和凋亡。应用Western blot检测细胞中P-glycoprotein(P-gP)、Akt和p-Akt蛋白的表达情况。结果:用LY294002处理A2780/Taxol细胞后细胞增殖速度变慢、对紫杉醇的半数抑制浓度(IC_(50))降低。实验组和对照组细胞的凋亡率分别是(2.64±0.90)%和(10.98±1.16)%(P<0.05)。LY294002处理后的Go/G,期细胞增加,S期明显减少,差异有统计学意义(P<0.05)。LY294002处理后的细胞与对照组相比P-gP和p-Akt的蛋白表达降低。结论:LY294002能够有效的逆转卵巢癌紫杉醇耐药细胞A2780/Taxol产生的多药耐药。

Objective： To study the effect of the phosphatidylinositol 3＇-kinase （PI3K/Akt） inhibitor LY294002 during chemother- apy on the paclitaxel-resistant ovarian cancer cell line A2780/Taxol. Methods： The effect of treatment with LY294002 on A2780/Taxol cell lines was determined based on the 50% inhibition concentration （ IC50 ） of paclitaxel, and on cell proliferation using the cholecysto- kinin octapeptide （ CCK-8 ） assay. The apoptotic rates and cell cycle stages were detected by flow cytometry. The expression of PI3K/ Akt, its phosphorylated form p-Akt, and phosphorylated P-glycoprotein （ P-gp ） protein was analyzed using Western blot. Results： The CCK-8 results showed that the proliferation of A2780/Taxol cell lines after 24 h since being treated with LY294002 was significantly slower compared with the untreated A2780/Taxol cell lines. The IC50 of paclitaxel in A2780/Taxol cells treated with LY294002 was also significantly lower than that in the original A2780/Taxol cell line. Flow cytometry demonstrated that the apoptotic ratio of the experi- ment group was significantly higher than that of the control group. Both groups showed some changes in the cell cycle, and there were statistically significant differences between the two groups （ P 〈 0.05 ）. Phosphorylated Akt and P-gp protein levels in A2780/Taxol cells were inhibited by LY294002, compared with the untreated A2780/Taxol cells. Conclusion： The PI3K/Akt inhibitor LY294002 has a reversal effect on the paclitaxel-resistance of the A2780/Taxol cell line.