miR-143 Inhibits Osteogenic Differentiation of Umbilical Cord Mesenchymal Stem Cell by Targeting Zinc Fingers and Homeoboxes 3

The transcription regulating factor-zinc fingers and homeoboxes 3 (ZHX3) involve in osteoblast differentiation. miR-143 regulates osteoblast differentiation. Bioinformatics analysis revealed a relationship between miR-143 and the 3'-UTR of ZHX3. This study assessed miR-143's role in UC-MSC differentiation. The UC-MSCs were induced to differentiate into osteoblasts. The expressions of miR-143, ZHX3, RUNX2, Osteopontin (OPN) and Osteocalcin (OC) genes were detected by qRT-PCR on days 0, 20 and 30. The UC-MSCs cells were divided into agomir-NC group and miR-143 agomir group. After 30 days of differentiation, the expression of ZHX3, RUNX2, OPN and OC protein was detected by western blot. During differentiation of UC-MSCs into osteoblasts, miR-143 expression was decreased, ZHX3 expression, ALP activity and alizarin red staining was increased. There was a targeted regulation relationship between miR-143 and ZHX3. Transfection of agomir-143 significantly downregulated ZHX3, RUNX2, OPN, OC genes and proteins, significantly reduced alizarin red staining, and decreased the ability of osteoblast differentiation. Decreased miR-143 expression plays a role in up-regulating ZHX3 expression and promoting osteoblast differentiation of UC-MSCs. Overexpression of miR-143 can inhibit UC-MSCs differentiation into osteoblasts by targeting ZHX3.