Tripartite motif 24 (Trim24/Tif1alpha) tumor suppressor protein is a novel negative regulator of interferon (IFN)/signal transducers and activators of transcription (STAT) signaling pathway acting through retinoic acid receptor alpha (Raralpha) inhibition
Fiche publication
Date publication
septembre 2011
Auteurs
Membres identifiés du Cancéropôle Est :
Pr CHAMBON Pierre, Mme THIBAULT-CARPENTIER Christelle
Tous les auteurs :
Tisserand J, Khetchoumian K, Thibault C, Dembele D, Chambon P, Losson R
Lien Pubmed
Résumé
Recent genetic studies in mice have established that the nuclear receptor coregulator Trim24/Tif1alpha suppresses hepatocarcinogenesis by inhibiting retinoic acid receptor alpha (Rara)-dependent transcription and cell proliferation. However, Rara targets regulated by Trim24 remain unknown. We report that the loss of Trim24 resulted in interferon (IFN)/STAT pathway overactivation soon after birth (week 5). Despite a transient attenuation of this pathway by the induction of several IFN/STAT pathway repressors later in the disease, this phenomenon became more pronounced in tumors. Remarkably, Rara haplodeficiency, which suppresses tumorigenesis in Trim24(-/-) mice, prevented IFN/STAT overactivation. Moreover, together with Rara, Trim24 bound to the retinoic acid-responsive element of the Stat1 promoter and repressed its retinoic acid-induced transcription. Altogether, these results identify Trim24 as a novel negative regulator of the IFN/STAT pathway and suggest that this repression through Rara inhibition may prevent liver cancer.
Référence
J Biol Chem. 2011 Sep 23;286(38):33369-79