Expression analysis of the TGF-β/SMAD target genes in adenocarcinoma of esophagogastric junction

The TGF-β/SMAD signaling pathway is found to play pivotal roles in cell growth, differentiation and tumorigenesis. Its target genes are closely related to the biological behaviors of some malignancies. The aim of this study was to analyze the expression of the target genes of this pathway, including growth-related c-myc, p21, p15, and metastasis-related Snail, ZEB1 and Twist1 in the adenocarcinomas of esophagogastric junction (AEJ) tissues. Clinical esophagogastric junction tissues from 25 cases of AEJ patients and 10 cases of non-tumorous tissues from the same site were collected. Quantitative real-time poly chain reactions were carried out to analyze the expression of the above referred target genes of TGF-β/SMAD pathway. A notable up-regulation in the mRNA expression of p15, Snail, ZEB1, down-regulation of c-myc, was found whereas there were no significant change of p21 and Twist1. The findings suggests that the TGF-β/SMAD pathway might be abnormally activated in AEJ since most of the target genes of this pathway exhibited altered expression at mRNA level.