RT-qPCR analyses of gene expression in DPCs grown in DMEM/10% FBS or STK2. DPCs (DPCs-2, DPCs-3 and DPCs-4) were cultured in DMEM/10% FBS or STK2 for 7 days. The mRNA levels of (A) TXNIP, (B) PGA3, (C) TNNT1, (D) SCRG1, (E) INHBF and (F) GLI1 were quantified by RT-qPCR analysis. Values are the means ± standard deviation of four replicate cultures. *P<0.05, **P<0.01, ***P<0.001 and ****P<0.0001 vs. DMEM/10% FBS in the same cell line. DPCs, dental pulp cells; DMEM/10% FBS, Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum; TXNIP, thioredoxin interacting protein; PGA3, pepsinogen 3; TNNT1, troponin T type 1; SCRG1, stimulator of chondrogenesis 1; INHBE, inhibin-βE; GLI1, GLI family zinc finger 1; RT-qPCR, reverse transcription-quantitative polymerase chain reaction.