Copy number alterations and copy-neutral loss of heterozygosity in ukrainian patients with primary myelofibrosis

Abstract

Aim: To examine frequencies and spectrum of genomic alterations in Ukrainian patients diagnosed with primary myelofibrosis (PMF). Materials and Methods: We enrolled 30 Ukrainian patients diagnosed with PMF who were previously tested for usual mutations in myeloproliferative neoplasms driver genes (JAK2, MPL and CALR). Genomic DNA samples were obtained from peripheral blood leukocytes of these patients. Copy number alterations and copy­neutral loss of heterozygosity (cnLOH) were assessed using a high­density CytoScan HD microarray platform. Statistical significance was evaluated by the Fisher exact test. Results: We identified frequent genomic alterations, but no significant difference in the rates of copy­number loss, copy­number gain, cnLOH, or multiple genomic alterations were found in the groups of PMF patients that were positive for one of the usual mutations in driver genes or negative for such mutations (33.3% and 55.6%, p = 0.4181, 19.0% and 11.1%, p = 1.0000, 61.9% and 44.4%, p = 0.4434, 33.3% and 55.6%, p = 0.4181, respectively). The most frequent alterations were cnLOH at 1p36­1p22, 9p24.3­9p13.3 and 11q12.3­11q25; copy number loss at 7q21­7q36.3 and 13q12.3­13q14.3. Copy number alterations and cnLOH commonly affected the EZH2, LAMB4, CBL, CUX1, ATM, RB1 and TP53 genes, in addition to JAK2, MPL and CALR. Conclusion: We demonstrated the spectrum of genomic alterations in the groups of the Ukrainian PMF patients with or without the usual mutations in the specific driver genes. We identified several potential genes, which may be involved in the myeloproliferative neoplasms development and their phenotype modification (EZH2, LAMB4, CBL, CUX1, ATM, RB1 and TP53).