BACKGROUND AND OBJECTIVE

Recent studies have revealed that TGF-beta/Smads signaling pathway plays a pivotal role in the oncogenesis and development of malignant tumors, and may closely relate to the biological behaviors of some malignant tumors, such as gastric carcinoma. This study was to investigate the expression of transforming growth factor-beta receptor II (TGF-betaRII), Smad4 and Smad7 proteins in gastric carcinoma, and explore their correlations to clinicopathologic characteristics and prognosis of gastric carcinoma.

METHODS

The expression of TGF-betaRII, Smad4, and Smad7 was detected by SABC immunohistochemistry and tissue microarray which containing 200 specimens of primary human gastric carcinoma and 56 specimens of adjacent gastric tissue.

RESULTS

The positive rates of TGF-betaRII, Smad4, and Smad7 in gastric carcinomas were 25.5%, 67.0%, and 47.0%, respectively. TGF-betaRII expression was related with depth of invasion, lymph node metastasis, tumor differentiation, and Lauren classification (Chi2=6.214, Chi2=11.308, Chi2=14.633, and Chi2=8.216, respectively, all P<0.05). Smad4 expression was related with tumor differentiation and Lauren classification (Chi2=16.162 and Chi2=13.100, all P<0.05). Smad7 expression was related with tumor differentiation and Lauren classification (Chi2=4.710 and Chi2=5.297, all P<0.05). Smad4 expression was positively correlated to TGF-betaRIIexpression (r =0.191, P=0.007). Smad4 expression was related with patients' survival (Chi2=4.090, P=0.043).

CONCLUSIONS

Abnormal expression of TGF-Smad signaling pathway proteins occurs in gastric carcinoma. Smad4-positive gastric carcinoma patients have better prognosis than Smad4-negative patients.