Clinical Significance of c-kit Protein Expression and c-kit Gene Mutation in Nasopharyngeal Cancer / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: The proto-oncogene c-kit is a receptor tyrosine kinase recognized to initiate essential signal transduction pathways that transmit biological signals for cellular proliferation, differentiation and metastasis. Aberrant expression or mutation of c-kit has been shown to be involved in the pathogenesis of many cancers. In this study, with the aim of identifying additional groups of tumors that may use the stem cell factor/c-kit pathway, we investigated the expression of c-kit in nasopharyngeal carcinoma. SUBJECTS AND METHOD: In this retrospective study, immunohistochemical stains for c-kit were performed on formalin-fixed paraffin embedded sections from 20 patients with nasopharyngeal carcinoma who were treated from 1996 to 2004. Gene mutation was analyzed by PCR-SSCP and direct sequencing. RESULTS: c-kit over-expression was found in 65% (13/20) of patients. Eight of the 13 samples (61.5%) exhibited strongly positive immunoreactivity for c-kit protein (staining of >50% of the tumor cells). c-kit gene mutation was found in 4 of 20 cases by the PCR-SSCP method. CONCLUSION: c-kit protein over-expre-ssion is found in 65% of the nasopharyngeal carcinoma patients. c-kit expression is correlated with c-kit DNA mutations and nasopharyngeal carcinoma may be potential targets for treatment with imatinib mesylate.