GSTP1 and psoriasis: Using two-dimensional (2D) gel electrophoresis, an early study identified 21 skin proteins, including eight proteins with 2-fold increased abundance in psoriasis lesions (SERPINB4, GSTP1, SERPINB5, ARHGDIA, HSPB1, KRT14, KRT17, YWHAQ) and two others with 2-fold decreased abundance (KRT15, CALR) [19].