Activated N-ras oncogenes in human neuroblastoma.

Abstract

Fifteen primary neuroblastomas and four bone marrow samples from neuroblastoma patients, representing clinical Stages I to IV, have been screened for mutations in codons 12, 13, and 61 of N-ras. Neuroblastoma DNAs were subjected to the polymerase chain reaction to amplify the relevant sequences and were then hybridized with specific oligonucleotides to locate and identify point mutations. The results show that one Stage I tumor contained an N-ras gene that was activated by a GC-CG transversion of the first base of codon 61, while in one Stage II tumor, activation of N-ras involved a GC-CG transversion of the first position of codon 13. N-ras activations were not detected in the six Stage III tumors and eight Stage IV tumors that were examined.