白桦酸对人胰腺癌细胞增殖、迁移、细胞周期和凋亡的影响

Influence of betulinic acid on proliferation,migration,cell cycle and apoptosis of pancreatic cancer cells

目的:研究白桦酸(BA)对人胰腺癌细胞(BxPC-3)增殖、迁移、细胞周期和凋亡的影响。方法:磺酰罗丹明B(SRB)方法测定BA对BxPC-3细胞的增殖抑制率,通过显微镜观察BxPC-3形态变化,用划痕法检测BxPC-3的迁移能力,流式细胞术检测BA对BxPC-3细胞周期的影响,Hoechst33342-PI双染色法观察细胞凋亡,Western Blot印迹检测Bcl-2,Bax的表达。结果:BA在体外明显抑制BxPC-3细胞的增殖,IC50为16.54 mg.L-1,BA在5 mg.L-1时即能抑制细胞的迁移;流式细胞术分析表明,BA可将BxPC-3细胞阻滞于G0期;Hoechst33342-PI双染显示,当BA质量浓度提高到20 mg.L-1以上,可见明显的凋亡细胞和死亡细胞;Western blot的结果说明,随着BA浓度的递增,Bax表达逐渐增加,Bcl-2表达逐渐减少,Bcl-2/Bax下降,并呈剂量依赖性。结论:BA具有明显抑制BxPC-3细胞增殖和迁移,诱导细胞凋亡的作用,有可能成为一个有效的治疗人胰腺癌药物。

Objective： To investigate the effect of betulinic acid（BA） on the proliferation,migration,apoptosis and cell cycle of pancreatic cancer cells（BxPC-3） in vitro and elucidate the underlying.Method： The effect of BA on the proliferation of BxPC-3 was measured by using sulforhodamine B（SRB） assay.Migratory ability of BxPC3 cells were detected by wound healing assay,and the morphological change was observed with light microscope.The influence of BA on cell cycle of BxPC-3 cells was tested by flow cytometry（FCM）.Apoptosis was analyzed by using Hochest33342-PI double staining.Western blot technologies were applied to detect the expression of Bcl-2 and Bax.Result： BA exhibited significant cell proliferation and migration inhibition,as well as its potency of inducing apoptosis in BxPC-3 cells in vitro in a dose-dependent manner.The IC50 value for 72 h was 16.54 mg·L-1.Cell migration was significantly inhibited at 5 mg·L-1 of BA.Cells treated with BA showed increased cell population in G0 phase,with decreased G2/M phase population.The expression of Bax and Bcl-2 was up and down-regulated respectively in BA-treated BxPC-3 cells in a dose-dependent manner.Conclusion： BA exerted potent effect on growth inhibition,G0 cell cycle arrest and induction of apoptosis in BxPC-3 cells in vitro,possibly associated with the down-regulation of Bcl-2 and up-regulation of Bax expression.The potent antitumor capacity of BA suggested that it could be a promising new anticancer agent in human pancreatic cancer treatment.