Jpn J Cancer Res  1993 Apr;84(4):379-87 

Clonal analysis of multiple point mutations in the N-ras gene in patients with
acute myeloid leukemia.

Kubo K, Naoe T, Kiyoi H, Fukutani H, Kato Y, Oguri T, Yamamori S, Akatsuka Y,
Kodera Y, Ohno R.

Department of Internal Medicine, Nagoya University Branch Hospital.

We have screened mutations of the N-ras gene at codons 12, 13, and 61 in
leukemia cells obtained from 100 patients with acute myeloid leukemia (AML), and
found mutated N-ras alleles in 9 patients. We further analyzed the polyclonality
of multiple N-ras gene mutations in 4 AML patients. One patient, who had the
monoclonal karyotype, t(11;17), had two types of double missense mutations at
codons 13 and 61 in the same allele. Each of the remaining three patients, one
of whom had t(15;17) with a monoclonal rearrangement of the retinoic acid
receptor alpha and PML genes, carried two missense mutations in a relatively
small population of leukemia cells. We have demonstrated that multiple clonality
of the N-ras gene is occasionally observed in leukemia with a monoclonal
karyotype. These findings indicate that the N-ras mutations may not always be
characterized simply by an accumulative process and that the activated N-ras
gene alone is not sufficient to cause leukemia.

PMID: 8514604 [PubMed - indexed for MEDLINE]