[Function of MEIS1 and miR-425 to the Regulating of Chronic Myeloid Leukemia Cell Proliferation]

To investigate the function and mechanism of transcription factor of MEIS1 and miR-425 to the proliferation of chronic myeloid leukemia cell K562.

Bioinformatic prediction was used to analyze the binding of MEIS1 in miR-425 promoter region. ChIP-qPCR coupled with dual luciferase assay was used to detect the combination of MEIS1 and the transcription activity of miR-425, and its regulative role in the transcription activity miR-425. CCK-8 was used to detect the effect of MEIS1 and miR-425 on cell proliferation. Flow cytometry with PI staining was used to detected the effect of MEIS1 and miR-425 on K562 cell cycle progression. Western blot was used to examine the effect of miR-452 on the expression level of MEIS1.

MEIS1 could bind the promoter of miR-425 and repressed its transcription. After K562 was transfected by shRNA, the K562 cell proliferation and cell cycle progression was significantly inhibitied. Moreover, after K562 cells were transfected by miR-425 mimic, cell proliferation and cell cycle was inhibited. The expression level of MEIS1 could be inhibited by the combination of miR-425 and MEIS1 3'UTR.

MEIS1 can inhibit the activity of miR-425 in transcriptional level, while the miR-425 can suppress the expression of MEIS1 protein in post-transnational level. Therefore, a regulatory circuit comprising from MEIS1 and miR-425 regulates K562 cell proliferation.