黄芪多糖对结肠癌SW620细胞增殖及凋亡作用的影响

目的:研究黄芪多糖对结肠癌细胞SW620增殖的影响,探讨其抗肿瘤机制。方法:体外培养的SW620细胞,分别给予黄芪多糖(0.1,0.2,0.4,0.6,0.8,1.0 g·L~(-1)),培养48 h后,用噻唑蓝(MTT)比色法检测黄芪多糖对人结肠癌细胞SW620增殖的影响;用1.0 g·L~(-1)黄芪多糖,体外培养SW620细胞48 h后,碘化丙啶(PI)单染检测药物处理后的肿瘤细胞周期,Annexin V/PI双染检测药物处理后的肿瘤细胞凋亡率;分别加入0.25,0.5,1.0 g·L~(-1)黄芪多糖,体外培养SW620细胞48 h后,通过蛋白免疫印记法(Western blot)检测B淋巴细胞瘤-2(Bcl-2),Bcl-2相关X蛋白(Bax),半胱氨酸蛋白酶(Caspase)-3,Caspase-9和细胞色素C的表达。结果:黄芪多糖能够抑制人结肠癌细胞SW620的增殖(P0.05,P0.01),且呈浓度依赖效应;与空白组比较,黄芪多糖1.0 g·L~(-1)处理组G2/M期比例增加,早期凋亡率增加,并且晚期凋亡率和总凋亡率均增加(P0.05,P0.01);与空白组比较,黄芪多糖0.25,0.5,1.0 g·L~(-1)组Caspase-3,Caspase-9,细胞色素C和促凋亡基因Bax表达量增加,Caspase-9前体和抗凋亡基因Bcl-2表达降低(P0.05,P0.01)。结论:黄芪多糖对结肠癌细胞SW620具有显著的抑制增殖和诱导凋亡作用,其诱导凋亡机制可能是通过线粒体凋亡通路实现的。

Effect of Astragali Radix Polysaccharides on Proliferation and Apoptosis of Human Colon Cancer Cell Line SW620

Objective: To observe the effect of Astragali Radix polysaccharides on the proliferation of colon cancer cell line SW620, and to explore its anti-tumor mechanism. Method: SW620 cells were cultured with different concentrations of Astragali Radix polysaccharides (0.1,0.2,0.4,0.6,0.8,1.0 g ·L^-1) in vitro for 48 h, and then treated with thiazole blue colorimetry (MTT) to detect the contents of Astragali Radix polysaccharides on the proliferation of human colon cancer cells SW620. Propidium iodide (PI) was used to detect the tumor cell cycle after treatment, and Annexin V/PI double staining was used to detect the apoptotic rate of tumor cells, while SW620 cells were cultured with Astragali Radix polysaccharides (1.0 g ·L^-1) for 48 h in vitro. The protein expressions of Caspase-3, Caspase-9, cytochrome C, Bax and Bcl-2 were detected by Western blot, while SW620 cells were cultured with Astragali Radix polysaccharides (0.25, 0.5, 1.0 g ·L^-1) for 48 h in vitro. Result: The growth of SW620 cells was significantly inhibited by APS in a dose-dependent manner (P<0.05, P<0.01). Compared with control group, the ratio of G₂/M phase in treatment group of Astragali Radix polysaccharide 1.0 g ·L^-1 was increased significantly (P<0.05, P<0.01). The early apoptosis rates, the late apoptosis rates and the total apoptosis rates were significantly higher than those in control group (P<0.05, P<0.01). Bax/Bcl-2 radio was significantly increased, and the expression of Caspase-9 was significantly decreased (P<0.05, P<0.01). The expressions of activated Caspase-3, activated Caspase-9 and cytochrome C were significantly increased (P<0.05, P<0.01). Conclusion: Astragali Radix polysaccharide could inhibit the proliferation of human colon cancer SW620 cells and induce the apoptosis of SW620 cells through mitochondrial pathway.