脂质体包裹MUC2反义核酸抑制胃癌细胞增殖的初步探讨

背景与目的：我们前期研究发现粘蛋白MUC2在胃癌组织中的表达与肿瘤的生物学行为密切相关。本研究拟观察MUC2反义脱氧寡核苷酸(antisense oligodeoxynucleotide,ASODN)对人胃癌细胞SGC7901生长抑制作用。方法：应用硫代磷酸修饰的MUC2 ASODN经阳离子脂质体包裹后转染入SGC7901细胞,采用MTT法、形态学观察测定MUC2 ASODN对SGC27901细胞的增殖抑制作用,免疫组化检测细胞中MUC2和p16蛋白的表达情况。结果：不同浓度ASODN均能抑制SGC7901细胞的增殖,在48h抑制作用最强,0．5μmol／L ASODN对细胞的抑制率为55％,随时间延长抑制作用逐渐减弱。SGC7901细胞转染MUC2 ASODN后,与对照组相比,光镜下观察到细胞数量减少、体积变小、核分裂明显减少、可见较多的坏死。透射电镜下见线粒体肿胀、细胞内脂滴增多、髓样结构、染色质边集等。免疫组化SP法染色显示转染ASODN后,SGC7901细胞MUC2蛋白表达水平明显降低,p16蛋白表达明显增强。结论：使用人工合成MUC2 ASODN能有效抑制人胃癌细胞SGC790l的增殖。

Inhibitory effect of MUC2 antisense oligodeoxynucleotide with lipofectin on human gastric cancer cell proliferation

BACKGROUND & OBJECTIVE: Our previous study showed that the expression of MUC2 protein was related with the biological behavior of gastric carcinoma. The aim of the present study was to investigate the inhibitory effect in vitro of mucin gene MUC2 antisense oligodeoxynucleotide (ASODN) on its gene expression and cell proliferation on gastric cancer cells SGC7901. METHODS: Phosphorothioate MUC2 ASODN was synthesized and transfected to SGC7901 cells mediated by lipofectin. Its inhibitory effects on cell proliferation was determined by MTT method, light and electron microscopy and immunohistochemical method. RESULTS: The determination by MTT method demonstrated that MUC2 ASODN of varied concentration significantly inhibited the growth of SGC7901 cells while the control lipofectin and control N-ODN showed no such effect. The inhibitory effect was dose-dependent and time-dependent. The inhibition peaked at 48th hour after transfection, and the inhibition rate reached 55% when the MUC2 ASODN concentration was 0.5 micromol/L. After transfecting with MUC2 ASODN, SGC7901 cells showed decrease in number, volume, and karyokinesis, and increase in necroses under light microscopy. Mitochondrion swelling, increased liposomes, myelin figures, chromatin margination were found under electron microscopy. And the test by immunohistochemical method indicated that transfected MUC2 ASODN downregulated the expression levels of MUC2 protein, but upregulated the expression levels of p16 protein. CONCLUSION: MUC2 ASODN transfection could specifically inhibit SGC7901 cells proliferation.