Affiliations: Laboratory Research Pathology, Graduate Program in
Pathology of Universidade Federal de Ciências da Saúde de Porto Alegre,
Porto Alegre, Brazil | Graduate Program in Medical Sciences of Universidade
Federal do Rio Grande do Sul, Rio Grande do Sul, Brazil | Laboratory Research Pathology of Universidade Federal
de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil | Department~of Clinical Medicine of Irmandade Santa
Casa de Misericórdia de Porto Alegre, Porto Alegre, Brazil | Department~of Pediatrics of Irmandade Santa Casa de
Misericórdia de Porto Alegre, Porto Alegre, Brazil
Note: [] Corresponding author: Laboratório de Pesquisa em Patologia
Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA),
Porto Alegre, Brazil. Tel.: +55 5133038802; E-mail: [email protected]
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.
