Expression and Prognostic Value of MiR-155 in Patients with Chronic Lymphocytic Leukemia

Abstract

To explore the expression of miR-155 in patients with chronic lymphocytic leukemia (CLL) and its correlation with the clinical and biological features in CLL. The expression of miR-155 was detected by quantitative real time polymerase chain reaction (qRT-PCR) in the peripheral mononuclear cells collected from 73 CLL patients and CD19 positive B cells collected from 60 healthy controls, respectively. The expression of miR-155 in CLL patients was compared with the healthy controls, and the correlation of miR-155 expression with the clinical characteristics of CLL patients such as age, sex, Binet stage, cytogenetic and molecular genetic, as well as the relationship of miR-155 expression level with time to treatment (TTT) and overall survival (OS) was further analysed. The expression of miR-155 was significantly elevated in CLL patients compared with the healthy controls. Further analysis showed that miR-155 expression decreased in the patients with the mutated immunoglobulin heavy chian variable region (IGHV) as compared with the patients unmutated (P＜0.05), and its expression was significant higher in the IGHV-39 family (P＜0.05). Fluorescence in situ hybridization (FISH) showed that the expression of miR-155 increased in patients with P53 mmutation/deletion and ATM deletion (P＜0.05). However, OS and TTT were not different between the patients with high and low expression of miR-155. MiR-155 is increasingly expresses in CLL patients and correlates with poor prognosis, suggesting its important role in the genesis and progress of CLL.