C/EBPα mRNA expression levels in HaCaT cells following treatment with 50, 70 or 90 ng/ml IL-17 for 24 h. (A) Representative reverse transcription-polymerase chain reaction result of C/EBPα mRNA expression levels in HaCaT cells. (B) C/EBPα mRNA expression levels were significantly downregulated following treatment with 50, 70 or 90 ng/ml IL-17 for 24 h. (C) Representative western blot of C/EBPα protein expression levels in HaCaT cells. (D) C/EBPα protein expression levels were significantly downregulated following treatment with 50, 70 or 90 ng/ml IL-17 for 24 h. *P<0.05, **P<0.01, ***P<0.001 vs. the control (0 ng/ml IL-17) group. C/EBP, CCATT/enhancer binding protein; IL, interleukin.