Author(s)

Eiichiro Hirakawa^1*, Yasunori Tokuhara¹, Tatsuya Morinishi¹, Hiroyuki Ohsaki², Erika Uemura³, Yukari Miki⁴, Toru Matsunaga³, Yoshio Kushida³, Reiji Haba³

¹Laboratory of Pathology, Department of Medical Technology, Kagawa Prefectural University of Health Sciences, Kagawa, Japan.
²Department of Medical Technology, Ehime Prefectural University of Health Sciences, Ehime, Japan.
³Department of Diagnostic Pathology, Kagawa University Hospital, Kagawa, Japan.
⁴Department of Medical Hygiene Technology Course, Kochi Gakuen College, Kochi, Japan.

Background: Cell adhesion molecule abnormalities are given as one reason for the occurrence of invasion and metastasis in various cancers. In this study, we conducted an immunohistochemical examination of cell adhesion molecule claudin-1 in mucosa and invasive front of gastric cancer, and investigated the correlation of claudin-1 expression and clinicopathological factors. Methods: Immunohistochemical examination was performed for 35 patients who underwent surgery be-tween January 2010 and October 2011, to assess the correlation of claudin-1 with primary gastric cancer. Results: The expression rate of claudin-1 was 48.6% (17/35) in 35 gastric carcinoma patients. The positive rates of claudin-1 were 42.9% (15/35) in mucosa and 28.6% (10/35) in invasive front of gastric cancer. The expression rate of claudin-1 in invasive front was lower than in mucosa. From comparing claudin-1 expression in mucosa, it was found that well-to moderately-differentiated adenocarcinoma had significantly more claudin-1 expression than poorly-differrentiated adenocarcinoma. Claudin-1 expression of well-to moderately-differentiated adenocar-cinoma decreased in the invasive front of gastric cancer. Expression of claudin-1 in mucosa was negative in many cases with advanced tumor invasion (T2, T3, T4) and positive in many cases with early tumor invasion (T1), with a significant difference between the two (p < 0.05). In mucosa, many cases at an advanced stage (Stage II, III, IV) were negative for claudin-1 expression and many cases at an early stage (Stage I) were positive for claudin-1 expression. A significant difference was seen between the two (p < 0.05). However, claudin-1 expression in the invasive front was not correlated with histological type, depth of tumor invasion and stage. Conclusion: From the above results, it is considered that decreased claudin-1expression in mucosa is related to histological type, gastric cancer invasion and stage, and this information may be useful when making a pathological diagnosis of advanced gastric cancer and estimating outcomes.

Claudin-1, Immunohistochemistry, Mucosa, Invasive Front, Gastric Cancer

Hirakawa, E. , Tokuhara, Y. , Morinishi, T. , Ohsaki, H. , Uemura, E. , Miki, Y. , Matsunaga, T. , Kushida, Y. and Haba, R. (2014) Down-Regulation of Claudin-1 Expression in Gastric Cancer Mucosa Is Correlated with Poor Prognosis. Open Journal of Pathology, 4, 206-212. doi: 10.4236/ojpathology.2014.44026.