title: Differential induction of connexins 26 and 30 in skin tumors and their adjacent epidermis.
abstract: Gap junctions (GJs) have been shown to play a role in tumor progression including a variety of keratinocyte-derived and non-keratinocyte-derived skin tumors. Here we show that the synthesis of the GJ proteins connexin 26 and connexin 30 (Cx26 and Cx30) is induced in keratinocyte-derived epithelial skin tumors whereas there is either no change or a downregulation of Cx43. Cx26, Cx30, and Cx43 are absent in non-epithelial skin tumors. Further, Cx26 and Cx30 are induced in the epidermis adjacent to malignant melanoma but absent in the epidermis adjacent to benign non-epithelial skin lesions (melanocytic nevi and angioma). The keratinocyte-derived skin tumors are very heterogeneous regarding the Cx26/Cx30 pattern in the epidermis at the periphery of the tumors. We did not observe any difference in the localization of the very similar proteins Cx26 and Cx30 but a variation in intensity of immunoreactivity. As the staining patterns of Cx26 and Cx30 antibodies are not identical to those of CK6, a marker for hyperproliferation, and CK17, a marker for trauma, we discuss that the induction of these gap junctional proteins exceeds a reflection of reactive hyperproliferative or traumatized epidermis. We further discuss the putative roles of these gap junctional proteins in tumor progression.
authors.affiliation: The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA. nhaass@wistar.org
authors.forename: Nikolas K
authors.initials: NK
authors.lastname: Haass
authors.forename: Ewa
authors.initials: E
authors.lastname: Wladykowski
authors.forename: Sabine
authors.initials: S
authors.lastname: Kief
authors.forename: Ingrid
authors.initials: I
authors.lastname: Moll
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Brandner
mesh_terms: D000818:Animals; D001913:Bowen's Disease / Q000378:metabolism; D002280:Basal Cell Carcinoma / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism; D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000096:biosynthesis*; D004817:Epidermis / Q000378:metabolism*; D006391:Hemangioma / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism; D007633:Keratins / Q000378:metabolism; D007642:Keratosis / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008545:Melanoma / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D009508:Nevus, Pigmented / Q000378:metabolism; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology; D014860:Warts / Q000378:metabolism
chemical_list: D000075302:Connexin 30; D017630:Connexins; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; C000607043:Gjb2 protein, mouse; D000072259:Connexin 26; D007633:Keratins