小檗碱增强丝裂霉素C诱导的膀胱癌T24细胞周期阻滞及凋亡

目的:研究小檗碱(berberine,Ber)增强丝裂霉素C(mitomycin C,MMC)诱导的人类膀胱癌T24细胞周期阻滞和细胞凋亡的作用及其相关机制。方法:将T24细胞分为4组:对照组、MMC组、MMC+Ber组和Ber组;采用CCK-8法检测不同药物处理后T24细胞的活力;采用流式细胞术分析不同药物处理后T24细胞周期的情况;Western blot检测细胞周期调控相关蛋白及凋亡相关蛋白的表达;Annexin V-FITC/PI双染后用流式细胞术检测各组细胞凋亡率。结果:CCK-8实验表明Ber能增强MMC抑制T24细胞活力的作用;流式细胞术检测细胞周期结果显示,MMC+Ber组T24细胞滞于G_0/G_1期(P0.05);与MMC组相比,MMC+Ber组p21和p27的蛋白表达上调(P0.05),cyclin D1、CDK2和CDK4的蛋白表达下调(P0.05),同时Ber促进MMC下调survivin的蛋白表达(P0.05);Annexin V-FITC/PI双染结果显示,Ber能促进MMC诱导的T24细胞凋亡(P0.05)。结论:Ber能显著增强MMC抑制T24细胞活力的作用,其机制可能是通过上调p21和p27,进而抑制cyclin D1、CDK2和CDK4表达;同时通过抑制survivin蛋白的表达,最终导致细胞被阻滞在G_0/G_1期,并促进细胞凋亡。

Berberine enhances mitomycin C-induced cell cycle arrest and apoptosis of T24 bladder cancer cells

AIM: To observe the effects of the combination of berberin (Ber) and mitomycin C (MMC) on the cell cycle arrest and apoptosis of T24 bladder cancer cells and the underlying mechanisms. METHODS: The T24 cells were exposed to MMC in the presence or absence of difference concentrations of Ber. The viability of the T24 cells was determined by CCK-8 assay. The cell cycle distribution was detected by flow cytometry. The apoptosis was analyzed by flow cytometry with Annexin V-FITC/PI staining, and the protein expression levels of cyclin D1, survivin, CDK2, CDK4, p21 and p27 were determined by Western blot. RESULTS: CCK-8 experiments showed that Ber enhanced the inhibitory effect of MMC on the viability of T24 cells. The results of flow cytometry showed that Ber also enhanced the blockade effect of MMC on T24 cells in G₀/G₁ phase (P<0.05). Compared with the MMC group, Ber increased the expression of p21 and p27 up-regulated by MMC, and decreased the expression of cynlin D1, CDK2 and CDK4 (P<0.05). Meanwhile, Ber promoted MMC to inhibit the expression of survivin (P<0.05). Ber increased the apoptosis of T24 cells induced by MMC (P<0.05). CONCLUSION: Ber significantly enhances the inhibitory effect of MMC on the viability of T24 cells. The mechanism may be related to up-regulation of p21 and p27, thereby inhibiting the expression of cyclin D1, CDK-2 and CDK-4. At the same time, Ber inhibits the protein expression of survivin, which eventually leads to cell arrest in G₀/G₁ phase and promotes apoptosis.