1p36, 19q13, 10q22-26, and O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status were assessed in 46 paired early and progressive oligodendrogliomas from 23 patients.
Oligodendrogliomas with a mutant IDH1 had noteworthy enhanced expression of enzymes controlling aerobic glycolysis and detoxification, and anti-apoptosis proteins.
CDKN2A HD did not correlate with histological grading (p = n.s.); however, it showed a correlation with survival (p = 0.03), supporting an important role of CDKN2A in the prognosis of oligodendrogliomas.
CSMD2 maps to a chromosomal region that may contain a suppressor of oligodendrogliomas, yet its expression is elevated in some head and neck cancer cell lines.
ZNF342 expression is specifically decreased in primary oligodendrogliomas and up-regulated in glioma cell lines treated with a demethylating agent, whereas the expression level of the adjacent gene, Gemin7, is not consistently altered in these samples.
DCX was highly expressed in both high-grade invasive tumors (glioblastoma, n=11; anaplastic astrocytoma/oligoastrocytoma, n=7; and medulloblastoma/PNET, n=6) and low-grade invasive tumors (oligodendroglioma, n=3; and astrocytoma/oligoastrocytoma, n=5).
alpha-Internexin (INA) is a proneural gene encoding a neurofilament interacting protein that is upregulated in some gliomas, particularly oligodendrogliomas.
IDH1 mutations were co-present with TP53 mutations in 63% of low-grade diffuse astrocytomas and with loss of heterozygosity 1p/19q in 64% of oligodendrogliomas; they were rare in pilocytic astrocytomas (10%) and primary glioblastomas (5%) and absent in ependymomas.