DNMT3B Oncogenic Activity in Human Intestinal Cancer Is Not Linked to CIMP or BRAFV600E Mutation

Published on Jan 14, 2020in iScience
路 DOI :10.1016/j.isci.2020.100838
Douglas J. MacKenzie2
Estimated H-index: 2
(Glas.: University of Glasgow),
Neil A. Robertson7
Estimated H-index: 7
(Glas.: University of Glasgow)
+ 8 AuthorsPeter D. Adams43
Estimated H-index: 43
(Glas.: University of Glasgow)
Summary Approximately 10% of human colorectal cancer (CRC) are associated with activated BRAFV600E mutation, typically in absence of APC mutation and often associated with a CpG Island Methylator (CIMP) phenotype. To protect from cancer, normal intestinal epithelial cells respond to oncogenic BRAFV600E by activation of intrinsic p53 and p16-dependent tumor suppressor mechanisms, such as cellular senescence. Conversely, CIMP is thought to contribute to bypass of these tumor suppressor mechanisms, e.g. via epigenetic silencing of tumor suppressor genes, such as p16. It has been repeatedly proposed that DNMT3B is responsible for BRAFV600E-induced CIMP in human CRC. Here we set out to test this by in silico, in vitro and in vivo approaches. We conclude that while both BRAFV600E and DNMT3B both harbor oncogenic potential in vitro and in vivo and show some evidence of cooperation in tumour promotion, they do not frequently cooperate to promote CIMP and human intestinal cancer.
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