title: Evaluation of the expression of C-kit (CD117) in ependymomas and oligodendrogliomas.
abstract: C-kit is a proto-oncogene located on the long arm of chromosome 4. Its product, CD117, is a specific immunohistochemical (IHQ) marker that is associated with response to a potent tyrosine kinase inhibitor therapy with STI-571 (Gleevec®) in chronic myelogenous leukemia and GISTs. In our study, we aimed to evaluate the expression of CD117 in glial tumors as this finding may guide therapeutic approaches for these brain tumors. Ependymomas and oligodendrogliomas, in formalin fixed and paraffin embedded blocks were assayed for CD117 immunoreactivity using anti-c-kit (CD117, DAKO). GISTs were used as positive control. We observed immunoreactivity of CD117 protein in 25.5% of tumors in both histological types. In oligodendrogliomas, there was an association between older age at diagnosis and positivity for CD117 (P=0.039). In addition, we observed an association between higher tumor grade (grade III) and positivity for CD117 (P=0.007). No clinical association was observed in ependymomas (P>0.05). This study encourages further investigations, considering that CD117 may be a possible oncogenic factor in some glial tumors. In this case, tumors that express this marker may eventually benefit from a therapy with selective inhibitors of receptor kinases.
authors: Laboratory Research Pathology, Graduate Program in Pathology of Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil. zavalhia@hotmail.com
authors: Lisiane Silveira
authors: LS
authors: Zavalhia
authors: Mirian
authors: M
authors: Romitti
authors: Gabriel Corteze
authors: GC
authors: Netto
authors: Giovana Tavares
authors: GT
authors: dos Santos
authors: Rosalva Thereza
authors: RT
authors: Meurer
authors: Arlete
authors: A
authors: Hilbig
authors: Mariana Bohns
authors: MB
authors: Michalowski
authors: Ligia Maria
authors: LM
authors: Barbosa Coutinho
authors: Marlise
authors: M
authors: de Castro Ribeiro
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002551:Cerebral Ventricle Neoplasms / Q000737:chemistry* / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D004806:Ependymoma / Q000737:chemistry* / Q000175:diagnosis; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000737:chemistry; D046152:Gastrointestinal Stromal Tumors / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D008875:Middle Aged; D009837:Oligodendroglioma / Q000737:chemistry* / Q000175:diagnosis; D000090063:Proto-Oncogene Mas; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis*; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D019009:Proto-Oncogene Proteins c-kit