TY - JOUR AU - Ahsan, Sama AU - Raabe, Eric H. AU - Haffner, Michael C. AU - Vaghasia, Ajay AU - Warren, Katherine E. AU - Quezado, Martha AU - Ballester, Leomar Y. AU - Nazarian, Javad AU - Eberhart, Charles G. AU - Rodriguez, Fausto J. PY - 2014 DA - 2014/06/03 TI - Increased 5-hydroxymethylcytosine and decreased 5-methylcytosine are indicators of global epigenetic dysregulation in diffuse intrinsic pontine glioma JO - Acta Neuropathologica Communications SP - 59 VL - 2 IS - 1 AB - Diffuse intrinsic pontine glioma (DIPG) is a malignant pediatric brain tumor associated with dismal outcome. Recent high-throughput molecular studies have shown a high frequency of mutations in histone-encoding genes (H3F3A and HIST1B) and distinctive epigenetic alterations in these tumors. Epigenetic alterations described in DIPG include global DNA hypomethylation. In addition to the generally repressive methylcytosine DNA alteration, 5-hydroxymethylation of cytosine (5hmC) is recognized as an epigenetic mark associated with active chromatin. We hypothesized that in addition to alterations in DNA methylation, that there would be changes in 5hmC. To test this hypothesis, we performed immunohistochemical studies to compare epigenetic alterations in DIPG to extrapontine adult and pediatric glioblastoma (GBM) and normal brain. A total of 124 tumors were scored for histone 3 lysine 27 trimethylation (H3K27me3) and histone 3 lysine 9 trimethylation (H3K9me3) and 104 for 5hmC and 5-methylcytosine (5mC). An H-score was derived by multiplying intensity (0–2) by percentage of positive tumor nuclei (0-100%). SN - 2051-5960 UR - https://doi.org/10.1186/2051-5960-2-59 DO - 10.1186/2051-5960-2-59 ID - Ahsan2014 ER -