[Study of nucleophosmin (NPM) gene mutation in patients with acute myeloid leukemia and myelodysplastic syndromes]

Abstract

Objective: To investigate nucleophosmin (NPM) gene mutations in patients with de novo acute myeloid leukemia (AML) with normal cytogenetics and primary myelodysplastic syndromes (MDS).

Methods: Genomic DNA corresponding to exon 12 of NPM gene was amplified by polymerase chain reaction (PCR) in 40 AML patients (28 case untreated and 12 in first remission) and 33 MDS patients. The PCR products were purified and screened by direct sequencing, the mutation PCR products were cloned into pUCm-T vector and then transfected into E. coil DH5alpha. At least 5 recombinant colonies were selected, and plasmid DNA were prepared and sequenced.

Results: NPM mutations were found in 6 patients (4 newly diagnosed AML and 2 MDS): 4 were type A,1 type B, and 1 novel sequence variant ( named as type R).

Conclusion: A new type of NPM mutation was found, and NPM mutations in MDS patients were demonstrated for the first time. The results provides new hints for NPM gene mutations in the pathogenesis of AML and MDS.