Abstract:

Objective To investigate the expression and activation of extracellular signal-regulated kinase 1/2（ERK1/2）, its upstream molecule, epidermal growth factor receptor （EGFR）, and downstream transcription factor, Ets-like protein 1 （ELK-1）, in lesions of psoriasis vulgaris, and to evaluate the relationship between ERK pathway and psoriasis vulgaris. Methods Tissue samples were obtained from the lesions of 40 patients with psoriasis vulgaris and normal skin of 20 normal human controls. Immunohistochemistry and Western blot were performed to detect the expressions of phosphorylated ERK1/2, EGFR and ELK-1 in the tissue samples. Results As immunohistochemistry showed, the integrated optical density （IOD） of p-ERK1/2, p-EGFR and p-ELK-1 was 269.85 ± 57.96, 136.88 ± 30.33 and 237.61 ± 56.29 respectively in the psoriatic lesions, significantly higher than that in the normal controls （140.24 ± 24.42, 110.66 ± 28.99 and 119.04 ± 21.99, respectively, all P < 0.05）. A positive correlation was observed between the expression of p-EGFR and p-ERK1/2 （r = 0.57, P < 0.05） and between that of p-ERK1/2 and p-ELK-1 （r = 0.72, P < 0.05） in psoriatic lesions. Conclusion The enhanced signal transduction through phosphorylated EGFR→ERK1/2→ELK-1 pathway may play a certain role in the pathophysiological process of psoriasis vulgaris.

Key words: Psoriasis, Epidermal Growth Factor receptors, Activating Transcription Factors.