Alpha-internexin (INA) is a proneuronal gene-encoding neurofilament interacting protein. INA is overexpressed mostly in oligodendroglial phenotype gliomas, is related to 1p/19q codeletion, and is a favorable prognostic marker. We studied INA expression in oligodendrogliomas (ODGs) and glioblastomas (GBMs) to verify its association with several molecular phenotypes, 1p/19q codeletion, and epidermal growth-factor-receptor (EGFR) amplification. A total of 230 low- and high-grade ODG and GBM cases was analyzed for INA expression by immunohistochemical staining; and 1p/19q and EGFR gene status was examined by fluorescence in-situ hybridization. INA was positive in 80.3% of ODGs and in 34.3% of GBMs. 1p/19q codeletion was detected in 77.0% of ODGs and 5.5% of GBMs. INA and 1p/19q codeletion were strongly correlated (P < 0.001). The specificity of INA expression for 1p/19q codeletion was 70.8%, while sensitivity was 100%; positive predictive value was 72.5%, and negative predictive value was 29.2% in all 228 tumors. INA expression was correlated with better progression-free survival (PFS) and overall survival (OS) (P = 0.001). In conclusion, INA expression has high specificity and sensitivity to predict 1p/19q codeletion, and it is well correlated with PFS of both ODGs and GBMs. Therefore, INA expression could be a simple, reliable, and favorable prognostic and surrogate marker for 1p/19q codeletion and long term survival.
Adult ; Brain Neoplasms/*metabolism/mortality/pathology ; Chromosomes, Human, Pair 1 ; Chromosomes, Human, Pair 19 ; Female ; Gene Deletion ; Glioblastoma/*metabolism/mortality/pathology ; Humans ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Intermediate Filament Proteins/genetics/*metabolism ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Oligodendroglioma/*metabolism/mortality/pathology ; Phenotype ; Predictive Value of Tests ; Prognosis ; Receptor, Epidermal Growth Factor/genetics/metabolism

OBJECTIVETo study the correlation between IDH1 mutation, MGMT expression, clinicopathologic features and post-radiotherapy prognosis in patients with astrocytoma.

METHODSDetection of IDH1 mutation and MGMT expression was carried out in 48 cases of astrocytoma (WHO grade II to III) by EnVision method with immunohistochemical staining. Follow-up data, including treatment response and overall survival time, were analyzed.

RESULTSThe rates of IDH1 mutation and MGMT expression in astrocytomas were 62.7% (30/48) and 47.9% (23/48), respectively. There was a negative correlation between IDH1 mutation and MGMT expression (r = -0.641, P < 0.01). The age of patients with IDH1 mutation was younger at disease onset. The IDH1 mutation rate in patients with WHO grade II astrocytoma was higher than that in patients with WHO grade III tumor (P < 0.05). The age at onset was an independent factor affecting the expression of mutant IDH1. After radiotherapy, patients with IDH1 mutation+/MGMT- tumor carried a longer overall survival time than patients with IDH1 mutation-/MGMT+ tumor (P < 0.05).

CONCLUSIONSThere is a correlation between IDH1 mutation and MGMT expression in WHO grade II to III astrocytoma. Age at onset is an independent factor affecting the expression of mutant IDH1. Tumors with IDH1+/MGMT- pattern show better response to radiotherapy than tumors with IDH1-/MGMT+ pattern. Detection of IDH1 mutation and MGMT protein expression can provide some guidance in choice of treatment modalities in patients with astrocytoma.

Adult ; Age Factors ; Age of Onset ; Aged ; Astrocytoma ; genetics ; metabolism ; mortality ; pathology ; radiotherapy ; Brain Neoplasms ; genetics ; metabolism ; mortality ; pathology ; radiotherapy ; DNA Modification Methylases ; metabolism ; DNA Repair Enzymes ; metabolism ; Female ; Humans ; Isocitrate Dehydrogenase ; genetics ; Male ; Middle Aged ; Mutant Proteins ; genetics ; Mutation ; Prognosis ; Tumor Suppressor Proteins ; metabolism

BACKGROUND: The purpose of the study is to reveal the association of cytogenetic compltyexi and peritumoral edema volume (PTEV) and its prognostic significance in high-grade astrocytoma patients by culturing patient tumor cells. METHODS: Twenty-seven high-grade astrocytoma patients were divided into three groups according to karyotype complexity: normal, non-complex karyotype (NCK), and complex karyotype (CK). Endothelial growth factor receptor (EGFR) amplification was detected by FISH, and its association with chromosome 7 abnormalities was analyzed. Mean PTEV of each group was compared by ANOVA to evaluate the relationship between PTEV and cytogenetic complexity. RESULTS: The PTEV of patients in normal (n=6), NCK (n=8), and CK (n=13) groups were 24.52±17.73, 34.26±35.04, and 86.31±48.7 cm3, respectively (P=0.005). Ten out of 11 patients with EGFR amplification showed abnormalities in chromosome 7. The mean PTEV of EGFR-amplified and non-amplified groups were 80.4±53.7 and 41.3±37.9 cm3, respectively (P=0.035). The average survival of patients with PTEV less than 90 cm3 was 30.52±26.11 months, while in patients with PTEVs over or equal to 90 cm3, it was 10.83±5.53 months (P=0.007). CONCLUSIONS: The results show an association of complex karyotype with the PTEV of high-grade astrocytoma. EGFR amplification plays a significant role in the formation of peritumoral edema, causing PTEV to increase, which is related with survival. This implies that cytogenetic karyotype can be applied as a prognostic factor.
Adult ; Aged ; Astrocytoma/diagnostic imaging/mortality/*pathology ; Brain Neoplasms/diagnostic imaging/mortality/*pathology ; Chromosome Aberrations ; Chromosomes, Human, Pair 7 ; Edema/diagnostic imaging/pathology ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Kaplan-Meier Estimate ; Karyotype ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neoplasm Grading ; Prognosis ; Receptors, Vascular Endothelial Growth Factor/metabolism ; Tumor Cells, Cultured ; Young Adult