Effect of SOX2 on odontoblast differentiation of dental pulp stem cells

The present study aimed to investigate the effect of SOX2 on odontoblast differentiation of dental pulp stem cells (DPSCs), and to examine the potential application of DPSCs on dental restoration. SRY-box 2 (SOX2) overexpression in human DPSCs (DPSCs-SOX2) was established by retroviral infection. The empty vector-infected DPSCs were regarded as a control group (DPSCs-vector group). Odontoblast differentiation culture medium was used to induce the differentiation of DPSCs. The degree of odontoblast differentiation of DPSCs was analyzed by flow cytometry. A genomic expression microarray and reverse transcription-quantitative polymerase chain reaction were used to analyze the molecular mechanism of SOX2 affecting odontoblast differentiation of DPSCs. After induction by odontoblast differentiation culture medium, the DPSC, DPSCs-vector and DPSCs-SOX2 groups all could carry out odontoblast differentiation. After induction for 3 weeks, all groups expressed dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) to a certain degree. However, after induction differentiation, the expression efficiency of DSPP and DMP-1 in the DPSCs-SOX2 group was highest compared with the normal DPSC and DPSCs-vector groups, which demonstrated the advantages of DPSC-SOX2 in odontoblast differentiation. Mechanism analysis indicated that in the DPSCs-SOX2 group, the activation of the Wnt signaling pathway and the upregulation of Wnt genes may be important mechanisms underlying SOX2 promoting odontoblast differentiation of DPSCs. These results preliminarily indicate that SOX2 has a certain promoting effect on odontoblast differentiation of DPSCs.