Loss of Trim24 (Tif1alpha) gene function confers oncogenic activity to retinoic acid receptor alpha.
Fiche publication
Date publication
décembre 2007
Journal
Nature genetics
Auteurs
Membres identifiés du Cancéropôle Est :
Pr CHAMBON Pierre, Dr METZGER Daniel, Dr TELETIN Marius, Mme THIBAULT-CARPENTIER Christelle, Mr LEROUGE Thierry
Tous les auteurs :
Khetchoumian K, Teletin M, Tisserand J, Mark M, Herquel B, Ignat M, Zucman-Rossi J, Cammas F, Lerouge T, Thibault C, Metzger D, Chambon P, Losson R
Lien Pubmed
Résumé
Hepatocellular carcinoma (HCC) is a major cause of death worldwide. Here, we provide evidence that the ligand-dependent nuclear receptor co-regulator Trim24 (also known as Tif1alpha) functions in mice as a liver-specific tumor suppressor. In Trim24-null mice, hepatocytes fail to execute proper cell cycle withdrawal during the neonatal-to-adult transition and continue to cycle in adult livers, becoming prone to a continuum of cellular alterations that progress toward metastatic HCC. Using pharmacological approaches, we show that inhibition of retinoic acid signaling markedly reduces hepatocyte proliferation in Trim24-/- mice. We further show that deletion of a single retinoic acid receptor alpha (Rara) allele in a Trim24-null background suppresses HCC development and restores wild-type expression of retinoic acid-responsive genes in the liver, thus demonstrating that in this genetic background Rara expresses an oncogenic activity correlating with a dysregulation of the retinoic acid signaling pathway. Our results not only provide genetic evidence that Trim24 and Rara co-regulate hepatocarcinogenesis in an antagonistic manner but also suggest that aberrant activation of Rara is deleterious to liver homeostasis.
Mots clés
Animals, Carcinoma, Hepatocellular, metabolism, Cell Proliferation, Genes, Tumor Suppressor, Hepatocytes, cytology, Liver Neoplasms, metabolism, Mice, Nuclear Proteins, genetics, Receptors, Retinoic Acid, genetics, Retinoic Acid Receptor alpha, Transcription Factors, genetics
Référence
Nat. Genet.. 2007 Dec;39(12):1500-6