Regulation of miRNA-618 on the proliferation and apoptosis of acute monocyte leukemia THP-1 cells / 白血病·淋巴瘤

ABSTRACT

Objective:To investigate the effect of miRNA-618 (miR-618) on the cell proliferation and apoptosis of acute monocyte leukemia THP-1 cells.Methods:Real-time polymerase chain reaction (PCR) was used to detect the relative expression level of miR-618 in THP-1 cells and monocytes isolated from peripheral blood of the healthy people. Overexpression of miR-618 plasimid vector was constructed and empty vector was treated as the negative control; and then the two vectors were transfected with THP-1 cells; finally, miR-618 overexpression group and negative control group were set. THP-1 cell proliferation and apoptosis of both groups were detected by using CCK-8 method and flow cytometry, respectively. TargetScan was used to predict the target gene of miR-618 and it was verified by using luciferase reporter assay.Western blot was used to detect the protein levels of THP-1 cells in miR-618 overexpression group and negative control group, and predicted miR-618 target gene in peripheral blood monocytes of the healthy people.Results:PCR showed that the expression level of miR-618 was lower in THP-1 cells compared with that in monocytes isolated from peripheral blood of the healthy people ( P < 0.05). CCK-8 assay showed that compared with the negative control group, the proliferation ability of THP-1 cells in miR-618 overexpression group was decreased (the absorbance values at 0, 24, 48 and 72 h after transfection 0.20±0.03 vs. 0.20±0.03, 0.28±0.02 vs. 0.35±0.03, 0.34±0.03 vs. 0.43±0.04, 0.39±0.02 vs. 0.53±0.05, all P < 0.05), and the late apoptosis rate was increased [(27.1±0.1)% vs. (14.9±0.1)%, t=2.13, P=0.03]. The target gene of miR-618 was ARPP19 predicted by using TargetScan software. Luciferase reporter assay showed that the relative luciferase activity of THP-1 cells in group transfected with wild-type ARPP19 gene plasmid+miR-618 gene plasmid was higher than that in the blank control group and group transfected with wild-type ARPP19 gene plasmid+miR-618 empty vector (0.170±0.003 vs. 0.100±0.004, 0.100±0.001, all P < 0.05). Western blot indicated the expression level of ARPP19 protein in THP-1 cells of miR-618 overexpression group was lower than that of the negative control group, while the expression levels of ARPP19 protein of peripheral blood monocytes of the healthy people in both groups were similar. Conclusion:miR-618 can inhibit the cell proliferation and promote apoptosis of THP-1 cells by inhibiting the expression of of THP-1 cells ARPP19 in acute monocyte leukemia.