Prognostic implication of N-RAS gene mutations in Egyptian adult acute myeloid leukemia.

Journal: The Egyptian Journal Of Immunology
Published:
Abstract

The pathogenesis of acute myeloid leukemia (AML) involves the cooperation of mutations promoting proliferation/survival and those impairing differentiation. Point mutations of the N-RAS gene are the most frequent somatic mutations causing aberrant signal-transduction in acute myeloid leukemia (AML). The aim of the present work is to study the frequency and prognostic significance of N-RAS gene mutations (N-RASmut) in de novo Egyptian adult AML. Bone marrow specimens from 150 patients with de novo acute myeloid leukemia and controls were analyzed by genomic PCR-SSCP at codons 12, 13 (exon 1), and 61 (exon 2) for N-RAS mutations. In 12.7% (19/150) AML cases, N-RAS gene mutations were found and were observed more frequently in the FAB subtype M4eo (P = 0.028) and with codon 12, 13 (14 of 19; 73.7%). Patients with N-RAS mutation had a significant lower peripheral and marrow blasts (P = 0.004, P = 0.03) and clinical outcome did not improve more than in patients without mutation. In patients with N-RAS gene mutation vs. those without, complete remission rate was (63.2% vs. 56.5%; P = 0.46), resistant disease (15.8% vs. 23.6%; P = 0.51), three years overall survival (44% vs 42%; P= 0.85) and disease free survival (42.1% vs. 38.9%, P = 0.74). Multivariate analysis showed that age was the strongest unfavorable factor for overall survival (relative risk [RR], 1.9; P = 0.002), followed by cytogenetics (P = 0.004). FAB types, N-RAS mutation and leukocytosis were the least important. In conclusion, the frequency and spectrum of N-RAS gene mutation differ between biologically distinct subtypes of AML but do not significantly influence prognosis and clinical outcome in patients with AML.

Authors
Doaa Elghannam, Nashwa Abousamra, Doaa Shahin, Enas Goda, Hanan Azzam, Emad Azmy, Manal El Din, Mohamed El Refaei