Expression of c-kit in human osteosarcoma and its relevance as a prognostic marker.
OBJECTIVE
To examine the prognostic relevance of c-kit expression in human osteosarcomas and to evaluate the mutation status in exon 9 and exon 11 of the c-kit gene.


METHODS
c-kit expression was examined in 100 human osteosarcomas by immunohistochemistry using paraffin embedded tumour tissues, and capillary sequencing of genomic DNA was performed to search for mutations in exons 9 and 11 of the c-kit gene.


RESULTS
20 osteosarcomas showed c-kit expression ranging from 5% to 90% (mean 5.9%; SD 16.74%). Furthermore, DNA sequences of exon 9 and exon 11 of the c-kit gene were not altered in these tumours. Overall and disease free survival analysis did not reveal any differences between patients with osteosarcoma with c-kit expression and those with c-kit negative tumours.


CONCLUSIONS
C-kit expression is not a prognostic marker in patients with osteosarcoma. The protein expression is not linked to mutations in exon 9 or exon 11 of the c-kit gene. Therefore, these exons may not function as targets for treatment modalities based on the suppression of c-kit tyrosine kinase activity.
Sulzbacher
Irene
I
Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria. irene.sulzbacher@meduniwien.ac.at
Birner
Peter
P
Toma
Cyril
C
Wick
Nikolaus
N
Mazal
Peter R
PR
D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001859:Bone Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002648:Child; D004252:DNA Mutational Analysis / Q000379:methods; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism*; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D019009:Proto-Oncogene Proteins c-kit