Ki-67 and MCM6 labeling indices are correlated with overall survival in anaplastic oligodendroglioma, IDH1-mutant and 1p/19q-codeleted: a multicenter study from the French POLA network.
Within the 1p/19q-codeleted AO, the contrast enhancement was associated with larger tumor volumes (P = .001), chromosome 9p loss and CDKN2A loss (P = .006), genomic instability (P = .03), and angiogenesis-related gene expression (P < .001), particularly for vascular endothelial growth factor A and angiopoietin 2.
Moreover, FAS expression was increased in glioblastomas (83.3%), anaplastic oligodendrogliomas and oligoastrocytomas (80%), and anaplastic astrocytomas (78.9%) compared with non-neoplastic lesions (20%).
Although independent expression of Bcl-2 was insufficient to induce tumors, suppression of apoptosis (detected by cleaved caspase-3 expression) was more pronounced in AOs induced by PDGFB and Bcl-2 compared to those induced by PDGFB alone.
Strikingly, hypermethylation of ZAR1 was observed frequently in diffuse astrocytomas (100%), anaplastic astrocytomas (94%), glioblastomas (93%), oligodendrogliomas (100%), anaplastic oligodendrogliomas (100%), and pituitary adenomas (90%), but not at all in pilocytic astrocytomas.
YKL-40 expression was higher in GBMs than AOs (P < 0.0001) and among GBMs, YKL-40 expression was lower in tumors with either EGFR amplification (P = 0.005) or elevated EGFR expression (P = 0.001).
When endogenous IGFBP2 expression was attenuated by an RCAS vector expressing antisense IGFBP2 in our mouse model, a decreased incidence of anaplastic oligodendroglioma as well as prolonged survival was observed.
CPT-11 demonstrated modest efficacy (similar to other salvage glioma regimens) with acceptable toxicity in this cohort of adults with recurrent, 1p19q co-deleted AO all of whom had failed prior TMZ chemotherapy.
CPT-11 demonstrated modest efficacy (similar to other salvage glioma regimens) with acceptable toxicity in this cohort of adults with recurrent, 1p19q co-deleted AO all of whom had failed prior TMZ chemotherapy.
In contrast, RTVP-1 and RTVP-1b showed similar patterns of expression in astrocytic tumors; highly expressed in glioblastomas as compared to normal brains, low-grade astrocytomas and anaplastic oligodendrogliomas.
In addition, we found that the cytosolic phospholipase A2 (PLA2G4C) gene at 19q13.3 demonstrated significantly lower expression in anaplastic oligodendrogliomas (WHO grade III) when compared to well-differentiated oligodendrogliomas (WHO grade II).
In addition, we found that the cytosolic phospholipase A2 (PLA2G4C) gene at 19q13.3 demonstrated significantly lower expression in anaplastic oligodendrogliomas (WHO grade III) when compared to well-differentiated oligodendrogliomas (WHO grade II).
The DNA repair enzyme O(6)-methylguanine DNA methyltransferase (MGMT) may cause resistance to DNA-alkylating drugs commonly used in the treatment of anaplastic oligodendrogliomas and other malignant gliomas.