BACKGROUND:microRNA-26b(miR-26b)plays an important regulatory role in a variety of stem cell functions,but its effects on the biological properties of stem cells from human exfoliated deciduous teeth and human umbilical cord mesenchymal stem cells are unknown. OBJECTIVE:To investigate the effects of miR-26b on the proliferation,migration and osteogenic differentiation of stem cells from human exfoliated deciduous teeth and human umbilical cord mesenchymal stem cells. METHODS:Stem cells from human exfoliated deciduous teeth and human umbilical cord mesenchymal stem cells were cultured and identified.miR-26 mimics(experimental group)and miRNAs mimics control(control group)were used to transfect above mentioned two kinds of cells and construct overexpressed models for subsequent experiments.CCK-8 assay was applied to detect the proliferation ability of overexpressed miR-26b cells.Transwell and scratch assay were employed to analyze the migration ability of overexpressed miR-26b cells.RT-qPCR was utilized to examine the expression of osteogenic markers after osteogenic induction of overexpressed miR-26b cells. RESULTS AND CONCLUSION:(1)Transfection of miR-26b mimics increased miR-26b expression in the two kinds of cells and promoted the proliferation of stem cells from human exfoliated deciduous teeth,with no significant effect on the amplification of human umbilical cord mesenchymal stem cells.(2)Compared with the control group,the migration ability was enhanced after two types of cells overexpressing miR-26b.(3)miR-26b expression decreased during osteogenic differentiation of the two kinds of cells.(4)Compared with the control group,the levels of osteogenesis-related genes osteocalcin,osteopontin,alkaline phosphatase,and human type I collagen mRNA were downregulated after overexpression of miR-26b in the two kinds of cells.The results showed that overexpression of miR-26b promoted the proliferation and migration of stem cells from human exfoliated deciduous teeth and inhibited their osteogenic differentiation;it promoted the migration of human umbilical cord mesenchymal stem cells and inhibited their osteogenic differentiation,but had no significant effects on their proliferation.