<i>IDH1</i> mutations only affected brainstem gliomas (6/24 vs 0/78; <i>p</i> = 7.5 × 10<sup>-5</sup>), were mostly non-R132H (contrasting with hemispheric gliomas, <i>p</i> = 0.0001), and were associated with longer survival (54 vs 12 months).
Small-size DNA (150-250 base pairs) was extracted from the plasma of 31 controls and 80 patients with glioma with known IDH1(R132H) status and correlated with MRI data.
Our results indicate the usefulness of assessing the R132H IDH1 mutation in glioma patients: the presence or absence of the R132H mutation can help pathologists to distinguish pilocytic astrocytomas (IDH1 WT) from diffuse ones (R132H IDH1/WT).
Mutations in the isocitrate dehydrogenase (IDH) 1 gene are commonly found in human glioma, with the majority of low-grade gliomas harboring a recurrent point mutation (IDH1 R132H).
This case suggests that 1p/19q co-deletion may rarely precede IDH1 mutations or that IDH1 mutations may be secondarily lost, as demonstrated by IDH1-R132H positive and negative cells in a glioma with diffuse 1p/19q co-deletion.
In conclusion, we established an anti-IDH1(R132H)-specific monoclonal antibody IMab-1, which should be significantly useful for diagnosis and biological evaluation of mutation-bearing gliomas.
Using murine glioma progenitor cells, we demonstrate that IDH1(R132H) exerts a growth-inhibitory effect that is paralleled by deficiency in metabolic flux from glucose and glutamine to lipids.
Of 158 tumors with sufficient tissue, 110 (70 %) showed nuclear cMYC immunopositivity--most frequent (95 %, χ(2) p = 0.0248) and intense (mean 1.33, ANOVA p = 0.0179) in anaplastic astrocytomas versus glioblastomas (63 %) or low grade gliomas (74 %). cMYC expression associated with younger age as well as p53 immunopositivity (OR = 3.6, p = 0.0332) and mutant IDH1 (R132H) (OR = 7.4, p = 0.06) among malignant gliomas in our cohort.
These results support a role for Fn14 in the more aggressive and invasive phenotype associated with IDH1 WT tumors and indicate that the low levels of Fn14 gene expression noted in IDH1 R132H mutant gliomas may be due to epigenetic regulation via changes in DNA methylation.
As IDH1(R132H) is present in all tumour cells of these slow-growing gliomas, a mutation-specific anti-IDH1(R132H) vaccine may represent a viable novel therapeutic strategy for IDH1(R132H)-mutated tumours.
We identified a single significant correlation resulting in increased overall survival from temozolomide in lower-grade glioma with IDH1 R132H mutations.
Activated leukocyte adhesion molecule expression in gliomas was independent of proliferative activity, MGMT status, patient survival, and age, whereas gliomas with IDH1 (R132H) mutation had significantly higher activated leukocyte adhesion molecule levels than their wild-type counterparts.
Isocitrate dehydrogenase (IDH) mutations, particularly IDH1 R132H (G395A), are found in WHO Grade II and III diffuse gliomas as well as secondary, but not primary, glioblastomas.
We developed and validated a new real-time quantitative polymerase chain reaction (PCR) assay for single-step detection of IDH1 R132H and 11 rare IDH1/2 mutations in formalin-fixed paraffin-embedded (FFPE) glioma samples.
The IDH1-R132H mutation predicts a better clinical outcome for glioma patients, and the expression of IDH1-R132H correlates with a favorable outcome in patients with brain tumors.
For this study, 164 cases of glioma were evaluated immunohistochemically for IDH1 mutations (R132H and R132S) using anti-IDH1 mAbs (HMab-1 and SMab-1).