TY - JOUR T1 - Non-canonical aberrant DNA hypermethylation in glioma JF - bioRxiv DO - 10.1101/193789 SP - 193789 AU - Agustin F. Fernandez AU - Gustavo F. Bayón AU - Marta I. Sierra AU - Rocio G. Urdinguio AU - Estela G. Toraño AU - Maria García AU - Antonella Carella AU - Virginia Lopez AU - Pablo Santamarina AU - Thalia Belmonte AU - Juan Ramon Tejedor AU - Isabel Cobo AU - Pablo Menendez AU - Cristina Mangas AU - Cecilia Ferrero AU - Luís Rodrigo AU - Aurora Astudillo AU - Ignacio Ortea AU - Sergio Cueto Díaz AU - Pablo Rodríguez-Gonzalez AU - J. Ignacio García Alonso AU - Manuela Mollejo AU - Bárbara Meléndez AU - Gemma Dominguez AU - Felix Bonilla AU - Mario F. Fraga Y1 - 2017/01/01 UR - http://biorxiv.org/content/early/2017/09/26/193789.abstract N2 - Aberrant DNA hypermethylation is a hallmark of cancer although the underlying molecular mechanisms are still poorly understood. To study the possible role of 5-hydroxymethylcytosine (5hmC) in this process we analyzed the global and locus-specific genome-wide levels of 5hmC in primary samples from 54 gliomas and 72 colorectal cancer patients. Levels of 5hmC in colorectal cancer were very low and no consistent changes were detected between control tissues and tumors. As expected, levels of 5hmC in non-tumoral brain samples were high and significantly reduced at the 49,601 CpG sites in gliomas. Strikingly, hypo-hydroxymethylation at 4,627 (9.3%) of these CpG sites was associated with aberrant DNA hypermethylation. The DNA regions containing these CpG sites were enriched in H3K4me2, and presented a different genuine chromatin signature to that characteristic of the genes classically aberrantly hypermethylated in cancer. We conclude that this data identifies a novel 5hmC-dependent non-canonical class of aberrant DNA hypermethylation in glioma. ER -