Detection of nucleophosmin and FMS-like tyrosine kinase-3 gene mutations in acute myeloid leukemia

BACKGROUND AND OBJECTIVES: Nucleophosmin gene mutations are frequently reported in acute myeloid leukemia (AML) patients with normal karyotype, which is also frequently associated with internal tandem duplication mutations in the FMS-like tyrosine kinase-3 gene. We sought to detect the nucleophosmin and FMS-like tyrosine kinase-3 (FLT3) internal tandem duplication (ITD) mutations among Iranian patients with AML and to assess the relationship between these mutations and the subtypes of the disease. DESIGN AND SETTING: Cross-sectional study of patients referred during 2007 through 2009. PATIENTS AND METHODS: Bone marrow and peripheral blood samples of 131 AML patients were randomly collected at the time of diagnosis and prior to treatment and the DNA extracted. After amplifying the nucleophosmin and FLT3 gene regions, positive cases were screened by conformation-sensitive gel electrophoresis and agarose gel electrophoresis techniques. RESULTS: Of 131 patients, 23 (17.5) (0.95 CI=0.107-0.244) had nucleophosmin gene mutations. The highest frequency of such mutations was found among the subtypes of M4 (30.4), M3 (21.7) and M5 (17.4). There was a high frequency of these mutations in the M3 subtype as well as a high frequency of allele D in all subtypes. Also, 21 (16.0) samples (0.95 CI=0.092-0.229) had FLT3/ITD mutation, of which 8 samples had mutant nucleophosmin (8 of 23, 35), and another 13 samples had wild-type nucleophosmin gene (13 of 108, 12). There was a high degree of association between the occurrence of nucleophosmin and FLT3/ITD mutations (P=.012). CONCLUSION: Our data showed a high frequency of NPM1 mutations in the monocytic subtypes of AML, as well as a high degree of association between the occurrence of NPM1 and FLT3/ITD mutations

Arsenic trioxide selectivity induces apoptosis within the leukemic cells of APL patients with t (15;16) translocation

Acute Promyelocytic Leukemia is a sub type of acute myelogenous leukemia that occurs in about 10-15 of patients with AML. Arsenic trioxide (ATO) as a single agent can induce remission in relapsed and newly diagnosed patients. Among all the arsenic putative functions responsible for these clinical responses, induction of differentiation and apoptosis with low and high doses are the most prominent mechanisms respectively. To evaluate the in vivo apoptotic pattern in leukemic cells of APL patients a single-laser, triple-color flowcytometric method was used, to detect leukemic apoptotic cells in a heterogeneous population of bone marrow samples with Annexin V and 7AAD. A substantial apoptosis which was selectively induced in Promyelocytic cells was detected during the early and middle stages of treatment. © 2006 Asian Network for Scientific Information

KIR2DS3 is associated with protection against acute myeloid leukemia

Background: Interaction between killer cell immunoglobulin-like receptors (KIR) and human leukocyte antigen (HLA) class I molecules is important for regulation of natural killer (NK) cell function. Objective: The aim of this study was to investigate the impact of compound KIR-HLA genotype on susceptibility to acute leukemia. Methods: Cohorts of Iranian patients with acute myeloid leukemia (AML; n=40) and acute lymphoid leukemia (ALL; n=38) were genotyped for seventeen KIR genes and their three major HLA class I ligand groups (C1, C2, Bw4) by a combined polymerase chain reaction-sequence-specific primers (PCR-SSP) assay. The results were compared with those of 200 healthy control individuals. Results: We found a significantly decreased frequency of KIR2DS3 in AML patients compared to control group (12.5 vs. 38, odds ratio=0.23, p=0.0018). Also, the KIR3DS1 was less common in AML group than controls (27.5 vs. 44.5, p=0.0465, not significant after correction). Other analyses including KIR genotypes, distribution and balance of inhibitory and activating KIR+HLA combinations, and coinheritance of activating KIR genes with inhibitory KIR+HLA pairs were not significantly different between leukemia patients and the control group. However, in AML patients a trend toward less activating and more inhibitory KIR-HLA state was observed. Interestingly, this situation was not found in ALL patients and inhibition enhancement through increase of HLA ligands and inhibitory combinations was the main feature in this group. Conclusion: Our findings may suggest a mechanism for escape of leukemic cells from NK cell immunity

The prognostic impact of WT1 expression levels, mutations, and SNP rs16754 in AML patients: A retrospective cohort study

Background & Objective: The clinical outcomes and treatment options for acute myeloid leukemia (AML) patients are highly dependent upon molecular markers. In this study, Wilms tumor 1 (WT1) (exons 7 and 9) mutations, single-nucleotide polymorphism (SNP) rs16754, and WT1 expression levels in 130 random AML patients were screened; FMs-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD), nucleophosmin (NPM1), and CCAAT/enhancer-binding protein alpha (CEBPA) mutations were also evaluated. Materials & Methods: Overall, 130 AML patients were recruited for this study. WT1 mutations were determined by Sanger sequencing, and expression levels were determined by real-time polymerase chain reaction (PCR). The Kaplan-Meier method was used to calculate overall survival (OS) and disease-free survival (DFS). Results: The frequency of WT1 mutations in the study population was 5.4, and it did not affect OS (P=0.98), DFS (P=0.97), or complete remission (CR) rates in AML patients. The major allele of SNP rs16754 in the current study was A. No significant differences were found for OS (P=0.52), DFS (P=0.42), or CR rates among all SNP rs16754 genotypes. The overexpression of WT1 was observed in 83 of patients at diagnosis. No significant difference was found for OS (P=0.84), DFS (P=0.82), or CR rates between AML patients with high and low WT1 expression levels. Conclusion: The results of the current study do not support WT1 mutation, SNP rs16754, or WT1 overexpression at diagnosis, as they were found to be poor prognostic markers in AML patients. © 2021, Zanjan University of Medical Sciences and Health Services. All rights reserved

FLT3-ITD compared with DNMT3A R882 mutation is a more powerful independent inferior prognostic factor in adult acute myeloid leukemia patients after allogeneic hematopoietic stem cell transplantation: A retrospective cohort study Allojenik hematopoetik kök hücre nakli sonrası yeti�kin akut myeloid lösemi hastalarında, FLT3-ITD, DNMT3A R882 mutasyonu ile kar�ıla�tırıldı�ında daha güçlü bir ba�ımsız kötü prognostik faktördür: Retrospektif kohort çalı�ması

Objective: This study aimed to evaluate DNMT3A exon 23 mutations and their prognostic impacts in the presence of NPM1 and FLT3 mutations in acute myeloid leukemia (AML) patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT). Materials and Methods: This study comprised 128 adult AML patients referred to the Hematology-Oncology and Stem Cell Research Center of Shariati Hospital. NPM1 and FLT3-ITD mutations were detected by fragment analysis. For DNMT3A exon 23 mutation analysis, we used Sanger sequencing. Overall survival (OS) and relapse-free survival (RFS) curves were estimated by the Kaplan-Meier method and the log-rank test was used to calculate differences between groups. Results: The prevalence of DNMT3A exon 23 mutations was 15.6 and hotspot region R882 mutations were prominent. RFS and OS were compared in patients with and without DNMT3A exon 23 mutations using univariate analysis and there was no significant difference between these groups of patients. On the contrary, the FLT3-ITD mutation significantly reduced the OS (p=0.009) and RFS (p=0.006) in AML patients after allogeneic HSCT. In the next step, patients with AML were divided into four groups regarding FLT3-ITD and DNMT3A mutations. Patients with DNMT3A R882mut/FLT3-ITDpos had the worst OS and RFS. These results indicate that DNMT3A mutations alone do not affect the clinical outcomes of AML patients undergoing allogeneic HSCT, but when accompanied by FLT3-ITD mutations, the OS was significantly reduced (5-year OS 0 for DNMT3A R882mut/ FLT3-ITDpos patients vs. 62 DNMT3A R882wt/FLT3-ITDneg, p=0.025) and the relapse rate increased. Conclusion: It can be deduced that DNMT3A R882mut/FLT3-ITDpos is an unfavorable prognostic factor in AML patients even after allogeneic HSCT. © 2018 by Turkish Society of Hematology