Abstract: Objective To investigate the effects of ZEB1 (Zinc finger E-box binding homeobox 1) gene knockdown on proliferation, cell cycle and apoptosis of human adipose-derived mesenchymal stem cells(hADSCs). MethodsPrimary mesenchymal stem cells were obtained from human adipose tissue by collagenase digestion and identified by immunological phenotype and differentiation potential of osteogenic and adipogenic lineages. The siRNA was transfected into hADSCs by lipofectamine 2000.The expression of ZEB1 and key proliferation, cell cycle and apoptosis-related genes were detected by real-time PCR and Western blot at mRNA and protein level respectively. The cell proliferation capacity was assessed by MTS. The apoptosis and cell cycle of hADSCs were evaluated by flow cytometry. ResultsThe ZEB1 expression at mRNA and protein level was significantly decreased in si-ZEB1 transfection cells compared to transfection with si-NC. Inhibition of ZEB1 decreased the cell proliferation ability, and significantly inhibited the expression of cell proliferation related genes,including CCND1,MKI67, MYC and PCNA. After transfection withsi-ZEB1, the percentage of cells in G1 phase increased from 50.17% to 58.94%, and S phase and G2 phase decreased by 6.16% and 2.07% separately.Meanwhile, the apoptosis rate increased by 10.2%, the expression of apoptosis related genes TP53 and BAX was up-regulated, and the expression of anti-apoptotic genes MCL1 and BCL2was down-regulated in si-ZEB1 transfection cells compared to transfection with si-NC. ConclusionsZEB1 may play an important role in promoting hADSCs proliferation, cell cycle progression and inhibit their apoptosis.

Key words: Key words：human adipose-derived mesenchymal stem cells, ZEB1, proliferation, cell cycle, apoptosis