P04.202-d fluorescence difference gel electrophoresis (dige) and mass spectrometry analysis in ependimomas: preliminary data

Despite the histological similarity of ependymomas from throughout the neuroaxis, the disease comprises multiple entities, depending on site of origin (spinal cord, posterior fossa and supratentorial) and patient age (children versus adults). Although detailed histological examination may identify important prognostic factors, their strength varies between subsets. Clinically, ependymomas remain an enigma to neuro-oncologists and neurosurgeons. Proteomic data on ependimomas are scant but a more detailed insight may complement cytogenetic and gene expression data in the effort to achieve a robust classification system of pediatric and adult ependymomas as a base for a molecular based therapy. RNA, DNA and proteins were extracted from 14 selected ependimomas. Proteins were analyzed with a 2-D Fluorescence Difference gel Electrophoresis (2D-DIGE) to compare proteomes. DIGE spots demonstrated significant difference in protein expression between selected types of ependimoma. Mass spectrometry analysis of these spots identified a high presence of GFAP and Albumin, Vimentin and Creatine kinase B-type. A new protein of particular interest - never described in ependimomas and other tumours of Central Nervous System - is FERM domain-containing protein 3 (FRMD3) (accession A2A2Y4). FRMD3 is as members of the 4.1 protein superfamily, which shares the highly conserved membrane-association domain FERM, which has already been linked to tumour suppressor activity. These preliminary data will be extended to more cases to discovery new biomarkers useful to integrate molecular data and possible validate diagnostic and/or prognostic factors.