Objective:To investigate the inhibitory effect in vitro of mucin gene MUC2 antisense oligodeoxynucleotide (ASODN) on its gene expression and cell proliferation on gastric cancer cell line.Methods:Phosphorothioate MUC2 ASODN were synthesized and transfected to SGC7901 cells mediated by lipofectin.Their inhibitory effects on cell proliferation were determined by MTT method

light microscopy and immunohistochemical method.Results:The determination by MTT method demonstrated that MUC2 ASODN of varied concentrations could significantly inhibit the growth of SGC7901 cell lines while the control lipofectin showed no such effect.The result also suggested that 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 concentration was 0.5μmol/L.After transfecting with MUC2 ASODN

SGC7901 cells showed decrease in number

volume and karyokinesis

increase in necroses under light microscopy.And the test by immunohistochemical method indicated that ASODN could downregulate the expression levels of MUC2 protein

MMP-2 protein and CD44V6 protein

but upregulate the expression levels of p16 protein.Conclusion:The data suggest that MUC2 ASODN transfection could effectively inhibit SGC7901 cells proliferation and invasion and metastasis potential of SGC7901 cells.