Downregulated miR-346 promotes the expressions of genes and proteins associated with migration and invasion. Mimics control, miR-346 mimics, inhibitor control, and miR-346 inhibitor were respectively transfected into HTR8/SVneo and JEG-3 cells. (A-F) Western blot and RT-qPCR analyses were performed to determine the expression levels of genes and proteins associated with migration and invasion (MMP-2, MMP-9, TIMP-1, TIMP-2). (G-L) Western blotting and RT-qPCR assays were used to determine the expression levels of LRP6 following transfection. **P<0.001; *P<0.05 vs. mimics control; ##P<0.001; #P<0.05 vs. inhibitor control (n=3). LRP6, low-density-lipoprotein receptor-related protein 6; MMP, matrix metalloproteinase; TIMP, tissue inhibitor of metalloproteinase.