白毛藤多糖通过调控miR-431表达对结直肠癌SW620细胞增殖及凋亡的影响

Effect of solanum lyratum polysaccharide on proliferation and apoptosis of colorectal cancer SW620 cells by regulating miR-431 expression

目的探讨白毛藤多糖对结直肠癌SW620细胞增殖、凋亡的影响及其对miR-431的调控作用。方法采用不同浓度(0.4,0.8,1.6 g/L)的白毛藤多糖处理SW620细胞,分别设为白毛藤多糖低剂量组、白毛藤多糖中剂量组、白毛藤多糖高剂量组;为探究miR-431在结直肠癌发生及发展过程中的作用机制,将miR-NC和miR-431 mimics分别转染入SW620细胞,命名为miR-NC组和miR-431组;为探讨miR-431是否可作为白毛藤多糖治疗结直肠癌的潜在靶点,将anti-miR-NC和anti-miR-431分别转染入SW620细胞后加入白毛藤多糖处理细胞,命名为白毛藤多糖+anti-miR-NC组和白毛藤多糖+anti-miR-431组。采用MTT实验检测细胞增殖抑制率;采用流式细胞术检测细胞凋亡率;采用qRT-PCR法检测miR-431的表达量。结果与对照组比较,白毛藤多糖低剂量组、白毛藤多糖中剂量组、白毛藤多糖高剂量组细胞增殖抑制率、细胞凋亡率和B淋巴细胞瘤-2相关蛋白(Bax)蛋白水平升高(P<0.05),miR-431的表达水平和增殖标记蛋白细胞增殖核抗原-67(Ki-67)、B淋巴细胞瘤-2(Bcl-2)蛋白水平降低(P<0.05),且呈剂量依赖性。与miR-NC组比较,miR-431组细胞增殖抑制率、细胞凋亡率和Bax蛋白水平升高(P<0.05),Ki-67、Bcl-2蛋白水平降低(P<0.05)。与白毛藤多糖+anti-miR-NC组比较,白毛藤多糖+anti-miR-431组细胞增殖抑制率、细胞凋亡率和Bax蛋白水平降低(P<0.05),Ki-67、Bcl-2蛋白水平升高(P<0.05)。结论白毛藤多糖可通过上调miR-431的表达而抑制结直肠癌细胞增殖及促进细胞凋亡。

Objective To explore the effect of solanum lyratum polysaccharide on the proliferation and the apoptosis of colorectal cancer SW620 cells and its regulatory effect on miR-431 expression.Methods SW620 cells were treated with 0.4,0.8,1.6 g/L solanum lyratum polysaccharide,respectively,named as solanum lyratum polysaccharide low-dose group,solanum lyratum polysaccharide medium-dose group,and solanum lyratum polysaccharide high-dose group.To explore the mechanism of miR-431 in the occurrence and development of colorectal cancer,miR-NC and miR-431 mimics were respectively transfected into SW620 cells in miR-NC group and miR-431 group.To explore whether miR-431 can be used as a potential target for the colorectal cancer treated with solanum lyratum polysaccharide,SW620 cells were respectively transfected with anti-miR-NC and anti-miR-431 and then treated with solanum lyratum polysaccharide in solanum lyratum polysaccharide+anti-miR-NC group and solanum lyratum polysaccharide+anti-miR-431 group.MTT experiment was used to detect the cell proliferation.Flow cytometry was used to detect the cell apoptosis.RT-qPCR method was used to detect the expression of miR-431.Results Compared with control group,the cell proliferation inhibition rate,the apoptosis rate,and the protein level of Bax in low-dose solanum lyratum polysaccharide group,medium-dose solanum lyratum polysaccharide group,and high-dose solanum lyratum polysaccharide group were increased(P<0.05),the expression level of miR-431 and the protein levels of Ki-67 and Bcl-2 were dose-dependently decreased(P<0.05).Compared with miR-NC group,the cell proliferation inhibition rate,the apoptosis rate and the protein level of Bax were increased in miR-431 group(P<0.05),while the protein levels of Ki-67 and Bcl-2 were decreased(P<0.05).Compared with solanum lyratum polysaccharide+anti-miR-NC group,the cell proliferation inhibition rate,the apoptosis rate,and the protein level of Bax were decreased in solanum lyratum polysaccharide+anti-miR-431 group(P<0.05),while the protein levels of Ki-67 and Bcl-2 were increased(P<0.05).Conclusion Solanum lyratum polysaccharide could inhibit the proliferation of colorectal cancer cells and promote the cell apoptosis by up-regulating the expression of miR-431.