OBJECTIVETo study the functional role of transforming growth factor beta1(TGFbeta1) in the regulation of epithelial-mesenchymal transition (EMT) and the effect of TGFbeta1-ASODN blockage of EMT in esophagus squamous cell carcinoma.

METHODSEsophageal squamous cell carcinoma cell line EC9706 was transfected with chemically synthesized TGFbeta1-ASODN. RT-PCR, immunohistochemistry and flow cytometry were used to detect the protein and mRNA expressions of TGF-beta1, E-cadherin and vimentin before and after the transfection. Morphological changes were documented and scarification test was used to detect the migration potential of EC9706 before and after the transfection.

RESULTSAfter TGFbeta1-ASODN transfection, mRNA (0.25 +/- 0.07) and protein (35.07% +/- 1.42%) expressions of TGFbeta1 in EC9706 were significantly lower than those before transfection (mRNA: 0.43 +/- 0.09; protein: 43.57% +/- 1.77%, chi(2) = 13.847 and chi(2) = 84.120, P < 0.05). The mRNA (0.38 +/- 0.09) and protein (17.13% +/- 1.45%) expressions of E-cadherin were significantly higher than those before transfection (0.22 +/- 0.06; 12.53% +/- 1.31%, chi(2) = 0.160 and chi(2) = 40.008, P < 0.05) and the mRNA (0.73 +/- 0.07) and protein (14.15% +/- 1.46%) expressions of vimentin were significantly lower than those (0.89 +/- 0.09; 17.97% +/- 1.42%) before transfection (chi(2) = 0.160 and chi(2) = 21.103, P < 0.05). Scarification test showed that after transfection, the mobility of EC9706 was significantly inhibited and its migration length (0.45 +/- 0.05) was significantly shorter than that before the transfection (0.81 +/- 0.11, chi(2) = 16.854, P < 0.05).

CONCLUSIONSTGFbeta1 may contribute to EMT in esophageal squamous cell carcinoma. TGFbeta1-ASODN leads to an over-expression of E-cadherin and a down-regulation of vimentin, along with the morphological alterations and migration inhibition, indicating that a blockage of TGFbeta1 suppresses EMT in esophagus squamous cell carcinoma.