Expression change of nm23-H1 in differentiation process of leukemia cells and its molecular mechanisms

Abstract

Objective To detect the mechanisms of nm23-H1, c-Myc, granulocyte colony-stimulating factor (G-CSF) in differentiation of leukemia cells HL-60 and their correlation, and provide theory basis and treatment targets for clinical treatment. Methods We chose CCK-8 assay to detect the proliferation change of the HL-60 cells induced by optimal concentration of all-trans-retinoic acid (ATRA). Wright Giemsa staining was used to observe cell morphological changes. The gene or protein expressions of nm23-H1, c-Myc and G-CSF were detected by reverse transcription-polymerase chain reaction (RT-PCR) or Western blotting assay, and the G-CSF secretion level in supernatants of ATRA-inducing HL-60 cells was measured by enzyme linked immunosorbent assay (ELISA). Results The cell proliferation inhibition rates were respectively (43.00±0.08)%, (49.55±2.30)%, (58.90±6.70)%, (64.60±4.70)%, (72.70±3.20)%, after HL-60 cells were induced by ATRA with drug concentrations of 0.25, 0.50, 1.00, 2.00 and 4.00 μmol/L for 72 hours, with a significant difference (F=69.887, P=0.000). After induced by ATRA, cell morphology confirmed that HL-60 cells were differentiated into mature granulocytes. The mRNA expression of nm23-H1 decreased gradually from 0.79±0.03 to 0.52±0.09. The difference was statistically significant (F=9.679, P=0.002). The relative expression of protein decreased from 1.54±0.12 to 0.40±0.04. The difference was statistically significant (F=90.140, P=0.000). The relative expression of c-Myc mRNA decreased from 0.95±0.05 to 0.46±0.05. The difference was statistically significant (F=27.900, P=0.000). The relative expression of protein decreased from 1.12±0.11 to 0.14±0.03. The difference was statistically significant (F=115.500, P=0.000). Moreover, the mRNA expression of G-CSF increased gradually from 0.26±0.07 to 0.55±0.09. The difference was statistically significant (F=7.817, P=0.004). The level of cell secretion increased from (13.67±7.51)pg/ml to (128.30±25.77)pg/ml. The difference was statistically significant (F=28.020, P=0.000). Conclusion nm23-H1 probably plays an important role in inducing differentiation of HL-60 cells by interacting with the expressions of c-Myc and G-CSF. Key words: Leukemia; Cell differentiation; Granulocyte colony-stimulating factor