BAALC, ERG, and WT-1 genes expressions in patients with acute myeloid leukemia and the comparison of the expressions before and after chemotherapy

Abstract

Acute myeloid leukemia (AML) is malignant clonal disorder of immature myeloid hematopoietic cells that is the most common type of acute leukemia among adults. This malignancy composes 80% of adult leukemia. The disease is heterogenic based on clinical and therapeutic characteristics which are due to cytogenetic and molecular differences. Clonal cytogenetic abnormalities are one of the important factors predicting clinical outcome in AML and are used to guide risk-adopted treatment strategies. Deregulated expression of genes encoding transcription factors involved in cell proliferation, survival or differentiation is known to be implicated in the process of leukemogenesis. Some of these gene are the brain and acute leukemia, cytoplasmic (BAALC), wilim's tumor, and ETS-related gene (ERG). Therefore, this study was designed to evaluate the expression of BAALC, WT-1 and ERG in patients with AML pre and post chemotherapy. Methods and material: forty patients with AML was entered to this cross-sectional study. In this study, the remained bone marrow samples, which were extracted from patients for flow cytometry and smear test for their therapeutic processes, were used. RNA was extracted from bone marrow samples after separation of AML cells. The expression of studied genes were measured using real time PCR. Then, the patients were undergone to chemotherapy with 3+7 standard regime (7 days with cytarabine and 3 days with daunorubicin or idarubicin). After chemotherapy, the expression of genes were measured in bone marrow of patients. Results: the mean age of the patients was 36.75±13.38 y and 50% of patients were male. The most and the least of patients were in M2 and M3 subgroups, respectively. The expression of BAALC, WT-1 and ERG were decreased significantly after chemotherapy (p= 0.017, 0.001 and 0.036, respectively).

There was no significant differences in gene expressions among AML subtypes (p>0.05). WT-1 expression was inversely and significantly correlated with platelet and neutrophil counts (p= 0.037 and 0.036, respectively).There was also inverse significant correlation between ERG expression and platelet count (p<0.001). Furthermore, BAALC expression was correlated with blast counts (p=0.034). The post-chemotherapy of WT-1 and pre-chemotherapy of BAALC gene expressions were correlated with low complete remission in AML patients (p=0.024 and 0.046).