Effect of Smad7 antisense oligodeoxynucleotide on the expression of MMP-2, TIMP-2 and proliferation in human pancreatic cancer cells SW1990

Abstract

Objective To investigate the effect of Smad7 antisense oligodeoxynucleotide (ASODN) on proliferation in human pancreatic cancer cell line SW1990,with a focus on the expression of matrix metalloproteinase-2(MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2).To explore the underlying mechanism of the role of Smad7 in the pathogenesis and development of pancreatic cancer.Methods Smad7 ASODN was transfected into SW1990 cells through lipofectamine.Nosense oligodeoxynucleotide (NSODN),ASODN and lipofectamine was used as control. The transfection efficiency was assessed by fluorescence microscopy and flow cytometry.The expressions of Smad7,MMP-2 and TIMP-2 in transfected cells were detected by RT-PCR and Western blot. Cell viability was assessed by dimethyl thiazoldiphenyltetrazoliumbromide (MTT) method. Results Smad7 was expressed in SW1990 cells.The transfection efficiency of SW1990 was 81.2％.The expressions of Smad7 mRNA were 0.34 ± 0.06,0.95 ±0.07,1.03 ± 0.11 in transfected group,ASODN and lipofectamine group; and the expressions of MMP-2 mRNAwere 0.54 ± 0.08,1.15 ± 0.13,1.27 ± 0.16 ; and the expressions of TIMP - 2 mRNA were 0.26 ±0.07,0.72 ± 0.13,0.78 ± 0.17,the mRNA expressions were significantly reduced in Smad7 ASODN transfected group,compared with other two groups (P ＜0.01 ).The expressions of Smad7 protein were 0.14 ± 0.03,0.29 ± 0.05,0.28 ± 0.07 in transfected group,ASODN and lipofectamine group; the expressions of MMP-2 protein were 0.17 ±0.02,0.29 ±0.05,0.31 ±0.04,and the expressions of TIMP-2 protein were 0.20 ± 0.03,0.41 ± 0.11,0.43 ± 0.09,the protein expressions were significantly reduced in Smad7 ASODN transfected group,compared with other two groups (P ＜0.01 ).The A490 values of proliferation were 0.83 ± 0.03,1.02 ±0.02,0.99 ±0.02 in transfected group,ASODN and lipofectamine group,the proliferation were significantly reduced in Smad7 ASODN transfected group,compared with other two groups (P ＜0.01 ).Conclusions Smad7 ASODN could effectively inhibit the expressions of Smad7,therefore decrease the expressions of MMP-2,TIMP-2 and reduce the proliferation. Key words: Pancreatic neoplasms ; Smad7 ; Antisense oligodeoxynucleotide; Matrix metalloproteinase-2; Tissue inhibitor of metalloproteinase-2; Cell proliferation