Abstract: Objective: To verify whether miR-218 could inhibit human trophoblastic cell (HTR-8 cells) migration and invasion by target-ing sex determining region Y-box 4(SOX4). Methods: The serum samples were collected from 46 hypertensive disorder complicating pregnan-cy (HDCP) and 50 normal pregnant women. RT-PCR was used to test the expression of miR-218 in the serum. In vitro, MiR-218 was trans-fe cted into HTR-8 cells. The HTR-8 cells were divided into three groups:normal control group, mimic control and miR-218 mimic group. The migratory and invasion ability of HTR-8 cells was tested, and the expressions of matrix metalloproteinase-2(MMP-2), MMP-9 and Sox4 were also investigated in the cells of each group. Luciferase assay was used to confirme whether Sox4-3'-UTR was the target gene of miR-218. Results: The expression of miR-218 was decreased in the serum of HDCP patients compared with the normal pregnant woman(P < 0.01). In vit-ro, compared with the control group, the invasion and migration ability of HTR-8 cells and the expression of MMP-2 MMP-9 and SOX4 were decreased in the miR-218 group (P < 0.01); The Luciferase activity of the SOX4-3'-UTR plasmid was significantly suppressed by miR-218 (P < 0.01); Over expression of SOX4 could reverse the effect of miR-218 on HTR-8 cells(P < 0.01). Conclusion: The expression of miR-218 decreases in the serum of HDPC patients and miR-218 inhibits HTR-8 cells invasion by targeting SOX4-3'-UTR.

Key words: hypertensive disorder complicating pregnancy (HDCP), miR-218, sex determining region Y-box 4, trophoblast cell, invasion