The CREB Coactivator CRTC2 Is a Lymphoma Tumor Suppressor that Preserves Genome Integrity through Transcription of DNA Mismatch Repair Genes

• Published in: Cell reports (Cambridge) Vol. 11; no. 9; pp. 1350 - 1357
• Main Authors: Fang, Minggang, Pak, Magnolia L., Chamberlain, Lynn, Xing, Wei, Yu, Hongbo, Green, Michael R.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 09.06.2015; Elsevier
• Subjects: Cell Line, Tumor; Chromatin Immunoprecipitation; DNA Mismatch Repair - genetics; Gene Expression Regulation, Neoplastic - genetics; Genes, Tumor Suppressor - physiology; Genome, Human; Humans; Immunoblotting; Lymphoma, T-Cell - genetics; Lymphoma, T-Cell - metabolism; Real-Time Polymerase Chain Reaction; RNA, Small Interfering; Transcription Factors - genetics; Transcription Factors - metabolism; Transcription, Genetic; Transfection
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2015.04.052

The CREB-regulated transcription coactivator CRTC2 stimulates CREB target gene expression and has a well-established role in modulating glucose and lipid metabolism. Here, we find, unexpectedly, that loss of CRTC2, as well as CREB1 and its coactivator CREB-binding protein (CBP), results in a deficiency in DNA mismatch repair (MMR) and a resultant increased mutation frequency. We show that CRTC2, CREB1, and CBP are transcriptional activators of well-established MMR genes, including EXO1, MSH6, PMS1, and POLD2. Mining of expression profiling databases and analysis of patient samples reveal that CRTC2 and its target MMR genes are downregulated in specific T cell lymphoma subtypes, which are microsatellite unstable. The levels of acetylated histone H3 on the CRTC2 promoter are significantly reduced in lymphoma in comparison to normal tissue, explaining the decreased CRTC2 expression. Our results establish a role for CRTC2 as a lymphoma tumor suppressor gene that preserves genome integrity by stimulating transcription of MMR genes. [Display omitted] •CRTC2, CREB1, and CBP are transcriptional activators of mismatch repair (MMR) genes•Loss of CRTC2, CREB1, or CBP leads to deficient MMR and increased mutation frequency•CRTC2 and its target genes are downregulated in specific T cell lymphoma subtypes•T cell lymphomas that have lost CRTC2 are microsatellite unstable The CREB-regulated transcription coactivator CRTC2 is known to modulate glucose and lipid metabolism. In this report, Fang et al. show that CRTC2 has an unexpected role as a lymphoma tumor suppressor gene that preserves genomic integrity by stimulating transcription of DNA mismatch repair genes.