Inactivation of TIF1gamma cooperates with Kras to induce cystic tumors of the pancreas. - Inserm - Institut national de la santé et de la recherche médicale Access content directly
Journal Articles PLoS Genetics Year : 2009

Inactivation of TIF1gamma cooperates with Kras to induce cystic tumors of the pancreas.

Julien C. Marie
Alain Puisieux
Jean-Yves Scoazec


Inactivation of the Transforming Growth Factor Beta (TGFbeta) tumor suppressor pathway contributes to the progression of Pancreatic Ductal AdenoCarcinoma (PDAC) since it is inactivated in virtually all cases of this malignancy. Genetic lesions inactivating this pathway contribute to pancreatic tumor progression in mouse models. Transcriptional Intermediary Factor 1 gamma (TIF1gamma) has recently been proposed to be involved in TGFbeta signaling, functioning as either a positive or negative regulator of the pathway. Here, we addressed the role of TIF1gamma in pancreatic carcinogenesis. Using conditional Tif1gamma knockout mice (Tif1gamma(lox/lox)), we selectively abrogated Tif1gamma expression in the pancreas of Pdx1-Cre;Tif1gamma(lox/lox) mice. We also generated Pdx1-Cre;LSL-Kras(G12D);Tif1gamma(lox/lox) mice to address the effect of Tif1gamma loss-of-function in precancerous lesions induced by oncogenic Kras(G12D). Finally, we analyzed TIF1gamma expression in human pancreatic tumors. In our mouse model, we showed that Tif1gamma was dispensable for normal pancreatic development but cooperated with Kras activation to induce pancreatic tumors reminiscent of human Intraductal Papillary Mucinous Neoplasms (IPMNs). Interestingly, these cystic lesions resemble those observed in Pdx1-Cre;LSL-Kras(G12D);Smad4(lox/lox) mice described by others. However, distinctive characteristics, such as the systematic presence of endocrine pseudo-islets within the papillary projections, suggest that SMAD4 and TIF1gamma don't have strictly redundant functions. Finally, we report that TIF1gamma expression is markedly down-regulated in human pancreatic tumors by quantitative RT-PCR and immunohistochemistry supporting the relevance of these findings to human malignancy. This study suggests that TIF1gamma is critical for tumor suppression in the pancreas, brings new insight into the genetics of pancreatic cancer, and constitutes a promising model to decipher the respective roles of SMAD4 and TIF1gamma in the multifaceted functions of TGFbeta in carcinogenesis and development.
Fichier principal
Vignette du fichier
journal.pgen.1000575.pdf (4.39 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

inserm-00420083 , version 1 (29-09-2009)



David F. Vincent, Kai-Ping Yan, Isabelle Treilleux, Fabien Gay, Vanessa Arfi, et al.. Inactivation of TIF1gamma cooperates with Kras to induce cystic tumors of the pancreas.. PLoS Genetics, 2009, 5 (7), pp.e1000575. ⟨10.1371/journal.pgen.1000575⟩. ⟨inserm-00420083⟩
220 View
206 Download



Gmail Facebook X LinkedIn More