Decreased Expression of Connexin-30 and Aberrant Expression of Connexin-26 in Human Head and Neck Cancer

• Published in: Anticancer research Vol. 27; no. 4B; pp. 2189 - 2195
• Main Authors: OZAWA, Hiroyuki, MATSUNAGA, Tatsuo, KAMIYA, Kazusaku, TOKUMARU, Yutaka, FUJII, Masato, TOMITA, Toshiki, OGAWA, Kaoru
• Format: Journal Article
• Language: English
• Published: Attiki International Institute of Anticancer Research 01-07-2007
• Subjects: Adult; Aged; Aged, 80 and over; Apoptosis - physiology; Biological and medical sciences; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - pathology; Cell Differentiation - physiology; Connexin 26; Connexin 30; Connexins - biosynthesis; Connexins - metabolism; Female; Head and Neck Neoplasms - metabolism; Head and Neck Neoplasms - pathology; Humans; Immunohistochemistry; In Situ Nick-End Labeling; Male; Medical sciences; Middle Aged; Mouth Mucosa - metabolism; Otorhinolaryngology (head neck, general aspects and miscellaneous); Otorhinolaryngology. Stomatology; Tumors; Human; Connexin; Cancerology; connexin 26; ENT disease; Head and neck cancer; Connexin 30; tumor suppressor; Malignant tumor; Tumor suppressor gene
• ISSN: 0250-7005; 1791-7530

Background: The relation of connexins and carcinogenesis has been studied in various organs and cell lines, with connexins
currently being considered tumor suppressors. Materials and Methods: The expression of connexin-26 (Cx26) and connexin-30
(Cx30) in human head and neck carcinomas, as well as in adjacent normal mucosa, was evaluated by immunohistochemistry. Furthermore,
the expression of these connexins with regard to apoptosis and cell differentiation was investigated. Results: In the cancer
tissues, Cx30 expression was drastically reduced compared to apparently normal mucosa while Cx26 expression was almost the
same. The intracellular distribution patterns of Cx26 and Cx30 in cancer cells differed between cancer locations. In the cancer
tissues, expression of Cx26 and Cx30 was not related to apoptosis assessed by TdT-mediated dUTP-biotin nick end labeling (TUNEL)
reaction or to cell differentiation assessed by immunoreaction to involucrin. Conclusion: The present results suggest that
connexins may play a role in the carcinogenesis of head and neck cancer.