title: EGF and TGF-β1 Effects on Thyroid Function.
abstract: Normal epithelial thyroid cells in culture are inhibited by TGF-β1. Instead, transformed thyroid cell lines are frequently resistant to its growth inhibitory effect. Loss of TGF-β responsiveness could be due to a reduced expression of TGF-β receptors, as shown in transformed rat thyroid cell lines and in human thyroid tumors, or to alterations of other genes controlling TGF-β signal transduction pathway. However, in thyroid neoplasia, a complex pattern of alterations occurring during transformation and progression has been identified. Functionally, TGF-β1 acts as a tumor suppressor in the early stage of transformation or as a tumor promoter in advanced cancer. This peculiar pleiotropic behaviour of TGF-β may result from cross-talk with signalling pathways mediated by other growth factors, among which EGF-like ligands play an important role. This paper reports evidences on TGF-β1 and EGF systems in thyroid tumors and on the cross-talk between these growth factors in thyroid cancer.
authors.affiliation: Department of Oncology and Experimental Medicine, University "G. d'Annunzio" Chieti-Pescara, 66013 Chieti, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Mincione
authors.forename: Maria Carmela
authors.initials: MC
authors.lastname: Di Marcantonio
authors.forename: Chiara
authors.initials: C
authors.lastname: Tarantelli
authors.forename: Sonia
authors.initials: S
authors.lastname: D'Inzeo
authors.forename: Arianna
authors.initials: A
authors.lastname: Nicolussi
authors.forename: Francesco
authors.initials: F
authors.lastname: Nardi
authors.forename: Caterina Francesca
authors.initials: CF
authors.lastname: Donini
authors.forename: Anna
authors.initials: A
authors.lastname: Coppa