Expression Pattern and Prognostic Significance of EVI1 Gene in Adult Acute Myeloid Leukemia Patients with Normal Karyotype

According to current criteria, patients with acute myeloid leukemia with normal karyotype (AML-NK) are classified as intermediate risk patients. There is a constant need for additional molecular markers that will help in substratification into more precise prognostic groups. One of the potential new markers is Ecotropic viral integration 1 site ( EVI1 ) transcriptional factor, whose expression is dissregulated in abnormal hematopoietic process. The purpose of this study was to examine EVI1 gene expression in 104 adult AML-NK patients and on 10 healthy bone marrow donors using real-time polymerase chain reaction method, and to evaluate association between EVI1 expression level and other molecular and clinical features, and to examine its potential influence on the prognosis of the disease. Overexpression of EVI1 gene ( EVI1 + status) was present in 17% of patients. Increased EVI1 expression was predominantly found in patients with lower WBC count ( P = 0.003) and lower bone marrow blast percentage ( P = 0.005). EVI1 + patients had lower WT1 expression level ( P = 0.041), and were negative for FLT3 - ITD and NPM1 mutations ( P = 0.036 and P = 0.003). Patients with EVI1 + status had higher complete remission rate ( P = 0.047), but EVI1 expression didn’t influence overall and disease free survival. EVI1 expression status alone, cannot be used as a new marker for more precise substratification of AML-NK patients. Further investigations conducted on larger number of patients may indicate how EVI1 expression could influence the prognosis and outcome of AML-NK patients, by itself, or in the context of other molecular and clinical parameters.