title: α-Internexin in the diagnosis of oligodendroglial tumors and association with 1p/19q status.
abstract: α-Internexin (INA) has been proposed to be a surrogate marker for the 1p/19q codeletion in oligodendroglial tumors (OTs). We analyzed INA expression in 83 glioma and 21 oligodendroglial phenotype-mimicking tumors (OMT) to assess its usefulness in differential diagnosis and its correlation with 1p/19q status; in particular, INA expression in gliomas with isolated/partial 1p or 19q deletions was assessed. α-Internexin expression and 1p/19q codeletion were present in 92% (34/37) of codeleted tumors (p < 0.0001). By contrast, INA was found in only 20% of cases with isolated/partial 1p aberrations and 36% of cases without 1p/19q deletions; it was also foundin 63% (10/16) of cases with isolated/partial 19q aberrations. α-Internexin expression was more specific in high-grade than in low-grade gliomas (66% vs 31%). Notably, a subset of tumors (10/83) displayed a biphasic INA expression pattern that was significantly associated with proliferation rate, whereas all areas harbored the 1p/19q codeletion. Only no or weak INA expression was seen in OMTs. In summary, INA is a useful marker to differentiate OTs from astrocytic tumors and OMTs, but INA expression is not exclusively linked to OTs harboring the 1p/19q codeletion. Moreover, it can sometimes be heterogeneously distributed within tumors, which emphasizes the need for 1p/19q analysis by molecular genetic techniques for diagnosis.
authors: Center for Neuropathology and Prion Research, Ludwig-Maximilians-University, Munich, Germany.
authors: Sabina
authors: S
authors: Eigenbrod
authors: Sigrun
authors: S
authors: Roeber
authors: Niklas
authors: N
authors: Thon
authors: Armin
authors: A
authors: Giese
authors: Anna
authors: A
authors: Krieger
authors: Eva
authors: E
authors: Grasbon-Frodl
authors: Rupert
authors: R
authors: Egensperger
authors: Jörg-Christian
authors: JC
authors: Tonn
authors: Friedrich-Wilhelm
authors: FW
authors: Kreth
authors: Hans A
authors: HA
authors: Kretzschmar
mesh_terms: D001932:Brain Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D002872:Chromosome Deletion; D002878:Chromosomes, Human, Pair 1; D002888:Chromosomes, Human, Pair 19; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006801:Humans; D007381:Intermediate Filament Proteins / Q000378:metabolism*; D018895:Microsatellite Repeats / Q000235:genetics; D009837:Oligodendroglioma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D013223:Statistics as Topic
chemical_list: D007381:Intermediate Filament Proteins; C046643:alpha-internexin