title: Alpha internexin expression related with molecular characteristics in adult glioblastoma and oligodendroglioma.
abstract: 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.
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul, Korea.
authors.forename: Ja Hee
authors.initials: JH
authors.lastname: Suh
authors.forename: Chul-Kee
authors.initials: CK
authors.lastname: Park
authors.forename: Sung-Hye
authors.initials: SH
authors.lastname: Park
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D002878:Chromosomes, Human, Pair 1; D002888:Chromosomes, Human, Pair 19; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005260:Female; D017353:Gene Deletion; D005909:Glioblastoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism*; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009837:Oligodendroglioma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D010641:Phenotype; D011237:Predictive Value of Tests; D011379:Prognosis
chemical_list: D007381:Intermediate Filament Proteins; C046643:alpha-internexin; D066246:ErbB Receptors
keywords: 1p/19q Codeletion; Alpha-internexin, humans; EGFR protein, Human; Glioblastoma; Oligodendroglioma