OCT4A contributes to the stemness and multi-potency of human umbilical cord blood-derived multipotent stem cells (hUCB–MSCs)

The OCT4A gene, a POU homeodomain transcription factor, has been shown to be expressed in embryonic stem cells (ESC) as well as hUCB–MSCs. In this study, the roles played by OCT4A in hUCB–MSCs were determined by stably inhibiting OCT4A with lenti-viral vector-based small hairpin RNA (shRNA). A decreased rate of cell proliferation was observed in OCT4-inhibited hUCB–MSCs. Down-regulation of CCNA2 expression in OCT4-inhibited hUCB–MSCs was confirmed by RT-PCR and real-time RT-PCR analysis in three genetically independent hUCB–MSC clones. Adipogenic differentiation was also suppressed in OCT4-inhibited hUCB–MSCs. The up-regulation of DTX1 and down-regulation of HDAC1, 2, and 4 expressions may be related to this differentiation deformity. The expression of other transcription factors, including SOX2, REX1 and c-MYC, was also affected by OCT4 inhibition in hUCB–MSCs. In conclusion, these finding suggest that OCT4A performs functionally conserved roles in hUCB–MSCs, making its expression biologically important for ex vivo culture of hUCB–MSCs.