Expression of claudin-5, -7, -8 and -9 in cervical carcinoma tissues and adjacent non-neoplastic tissues

Recent data indicate that the tight junction proteins are abnormally regulated in several human cancers and the expression of these proteins is involved in the etiology and progression of cancer. To explore the expression distinction of the tight junction proteins claudin-5, -7, -8 and -9 in the adjacent non-neoplastic tissues and cervical carcinoma tissues, 72 cervical carcinoma tissues and the samples of non-neoplastic tissues adjacent to the tumors were examined for expression of claudin-5, -7, -8 and -9 by streptavidin-perosidase immunohistochemical staining method. The positive expression rates of claudin-5 in cervical carcinoma tissues and adjacent non-neoplastic tissues were 31.9% (23/72) and 51.4% (37/72) respectively (P < 0.05). The positive expression rates of claudin-7 in cervical carcinoma tissues and adjacent non-neoplastic tissues were 47.2% and 50.0% respectively (P = 1.000). The positive expression rates of claudin-8 in cervical carcinoma tissues and adjacent non-neoplastic tissues were 54.2 % and 27.8% respectively (P < 0.01). The positive expression rates of claudin-9 in cervical carcinoma tissues and adjacent non-neoplastic tissues were 38.9% and 56.9% respectively (P < 0.05). Thus in our study, the expression of claudin-5 and claudin-9 was down-regulated while the expression of claudin-8 was up-regulated in cervical carcinoma tissues compared with adjacent non-neoplastic tissues. The expression of claudin-7 has no obviously difference between cervical carcinoma tissues and adjacent non-neoplastic tissues. In addition, correlations between claudin-5, -8 and -9 expression with lymphatic metastasis were observed. Our study reveals that the expression of claudin-5, -8 and -9 altered between in cervical carcinoma tissues and adjacent non-neoplastic tissues.