ST6Gal I 基因特异性siRNA对SW480细胞黏附和侵袭力的影响

目的:探讨人α-2,6-唾液酸转移酶(ST6GalI)小分子干扰RNA(siRNA)对ST6GalI高表达的结肠癌SW480细胞株的黏附和侵袭力的影响。方法:设计并合成ST6GalI靶向的siRNA,用脂质体Lipofectamine2000包裹后转染SW480细胞。实验设空白对照组、脂质体对照组、非特异性siRNA组和ST6GalIsiRNA组,采用RT-PCR测定细胞中ST6GalImRNA表达水平,流式细胞术检测细胞表面α-2,6-唾液酸含量,并分别用CytoMatrixTM细胞黏附试剂盒及细胞侵袭分析试剂盒,检测细胞对细胞外基质(ECM)黏附与侵袭力。结果:与空白对照组、脂质体对照组、非特异性siRNA组相比,转染48h后,ST6GalIsiRNA组细胞中ST6GalImRNA表达明显下调;转染72h后,ST6GalIsiRNA组细胞表面α-2,6-唾液酸的含量及细胞对ECM的黏附和侵袭力均明显低于其他3个对照组(P<0.05)。结论:化学合成的靶向ST6GalI的siRNA能够下调SW480细胞中ST6GalI基因的表达,降低细胞对ECM的黏附和侵袭力。本实验为进一步研究应用RNA干扰技术抗肿瘤治疗奠定基础。

Effect of ST6Gal I siRNA-mediated gene silencing on the adhesion and invasion of SW480 cells

AIM: To study the effect of synthesized ST6Gal I specific siRNA on the adhesion and invasiveness of human colon carcinoma cell line SW480 with over expression of ST6Gal I. METHODS: A double strand small interference RNA (siRNA) targeting ST6Gal I was designed and synthesized, and then transfected into SW480 cells by lipofectmine 2000. SW480 cells were cultured and divided into 4 groups: blank control group, liposome control group, non-specific siRNA group and ST6Gal I siRNA group. The expression of ST6Gal I mRNA was examined by RT-PCR and the amount of alpha-2, 6-sialylation on the SW480 cell surface was detected by flow cytometry. The adhesion and invasion of SW480 cells to extracellular matrix (ECM) were analyzed by using CytoMatrix kit and cell invasion assay kit, respectively. RESULTS: After SW480 cells were transfected for 48 hours, the expression of ST6Gal I mRNA in ST6Gal I siRNA group was significantly decreased compared with that in the blank control group, liposome control group, and non-specific siRNA group (P<0.05). After SW480 cells were transfected for 72 hours, the amount of alpha-2, 6-sialylation on cell surface, the adhesion and invasion of the cells in ST6Gal I siRNA group were markedly lower than those in the other 3 groups (P<0.05). CONCLUSION: The chemically synthesized specific siRNA targeting ST6Gal I can effectively inhibit the expression of ST6Gal I and reduce cell adhesion and invasion to ECM in SW480 cells. Our research is important for further study of anti-tumor treatment with RNA interference.