Expression of miRNA-155 in Uygur patients with chronic lymphocytic leukemia and its clinical significance

Abstract

Objective To explore the expression of miRNA-155 (miR-155) in CD19+ B lymphocytes in Uygur patients with chronic lymphocytic leukemia (CLL), and to analyze its clinical significance. Methods Peripheral blood (10-15 ml) samples of 30 Uygur CLL patients, 20 Han CLL patients, 10 Han healthy people and 10 Uygur healthy people were collected. Mononuclear cells were isolated and B lymphocytes were purified by using CD19+ magnetic-bead system. Total RNA was extracted from CD19+ B lymphocytes. The expression of miR-155 was measured by using TaqMan probe method. All the results were analyze combined with the clinical data of patients. Results The expression level of miR-155 in Han and Uygur CLL patients had no statistical difference (5.994±1.156 vs. 5.856±1.359, t= 0.556, P= 0.710), which was significantly higher than that in the healthy controls (t= 18.612, P 0.05). The expression level of miR-155 had a significant statistical difference between ZAP-70 negative group and ZAP-70 positive group (5.7 ± 1.1 vs. 6.5 ± 1.4, t= 1.575, P= 0.029). The expression level of miR-155 also had a statistical difference between mutated immunoglobulin heavy chain variable region (IGHV) and unmutated IGHV (5.3 ± 1.1 vs. 6.5 ± 1.1, t= 0.210, P= 0.001). The expression level of miR-155 was 5.4 ± 1.2, 5.7 ± 0.7, and 6.6 ± 1.5 in the favorable prognosis group, moderate prognosis group and poor prognosis group respectively (F= 3.609, P= 0.035); The expression levels of miR-155 had significant differences between moderate group and poor prognosis group (P= 0.032), favorable group and poor prognosis group (P= 0.007). Conclusions The expression of miR-155 in Han and Uygur CLL patients has no significant difference. High-level expression of miR-155 is associated with the poor prognosis of CLL patients. Key words: Leukemia, lymphocytic, chronic; MicroRNAs; MicroRNA-155; Minority groups