%0 Journal Article %T Snail Protein Expression as a Hallmark of Gastric Carcinoma in Biopsy Samples %A Hiroyuki Tanishima %A Ting Gui %A Yujing Sun %A Aiko Shimokado %A Takashi Ozaki %A Yasuteru Muragaki %J ISRN Pathology %D 2012 %R 10.5402/2012/132472 %X Overexpression of the Snail gene transcriptional repressor promotes an epithelial-to-mesenchymal transition (EMT) in epithelial tumor cell lines. In this study, we aimed to determine the correlation between Snail protein expression and clinicopathological features and to test whether Snail can be used as a marker to distinguish gastric carcinomas from benign tissues in biopsy samples. The results of immunohistochemistry with an antibody against Snail showed that most adenocarcinomas had positive Snail expression, whereas weak Snail expression was detected in a small number of gastritis and gastric adenomas. Snail-positive cells were detected in the stroma as well as in the glandular epithelium in some adenocarcinomas. In addition to Snail immunostaining, immunostaining of the EMT-related molecules, E-cadherin and vimentin, was performed. E-cadherin was not detected in adenocarcinomas that expressed Snail, whereas gastritis and adenomas stained positively for E-cadherin. Vimentin expression was seen in adenocarcinomas with positive Snail expression, whereas gastritis and adenomas did not express vimentin. In conclusion, we propose that Snail is a useful biomarker to distinguish gastric adenocarcinomas from benign lesions in biopsy samples. 1. Introduction The transcription factor Snail is a zinc finger protein that represses transcription of the E-cadherin gene through an interaction of the Snail COOH-terminal region with a 5กไ-CACCTG-3กไ sequence called the E-box in the E-cadherin promoter region [1]. The loss of E-cadherin expression has been shown to be responsible for the loss of cell-cell adhesion and cell polarity that occurs during the early stages of invasion and metastasis of carcinoma cells [1]. During the process of tumor invasion, tumor cells lose their properties of cell-cell adhesion and frequently undergo profound changes in their phenotype known as epithelial-to-mesenchymal transition (EMT) [2]. Snail is one of the most important regulators of EMT [3]. Gastric cancer is the most common malignant tumor in Japan. In 1998, more than 100,000 new cases were reported. By 2015, it is anticipated that this number will climb to nearly 150,000 [4]. The only potentially curative treatment for gastric cancer is surgical resection of all gross and microscopic disease. Deciding which type of surgery to perform is one of the most important surgical issues in this disease. Recent advances in endoscopy have allowed easy exploration of the stomach by gastroenterologists. However, the final diagnosis of gastric cancer and the definitive treatment still %U http://www.hindawi.com/journals/isrn.pathology/2012/132472/