Fig. 5.
Effects in mel-NF1 cells of specific inhibitors targeting downstream signaling pathways of neurofibromin on melanogenesis. (A) Western blot analysis of phospho-p44/42 MAPK (ERK1/2) after PD0325901 treatment in mel-NF1-1 and NF1-2 cells. Total ERK served as a control (n = 2). (B) Western blot analysis of tyrosinase and DCT expression after PD0325901 treatment in mel-NF1-1 and NF1-2 cells. β-actin served as a loading control (n = 2). (C) Direct ELISA analysis of cAMP content in mel-NF1-1 and NF1-2 cells after HA1004 treatment. Measurements were performed using 105 cells of each cell type. Results were normalized to mel-NF1 control and are expressed as mean ± SD (n = 3). (D) Melanin content in mel-NF1-1 and NF1-2 cells after HA1004 treatment. Measurements were performed using 105 cells of each cell type. Results were normalized to mel-NF1 control and are expressed as mean ± SD (n = 3). (E) Western blot analysis of tyrosinase and DCT expression after HA1004 treatment in mel-NF1-1 and NF1-2 cells. β actin served as a loading control. (F) Melanin content after treatment of mel-NF1-1 and mel-NF1-2 cells with various concentrations of kojic acid. Results are expressed as mean ± SD (n = 3). (G) Western blot analysis of tyrosinase and DCT expression after treatment with various concentrations of kojic acid in mel-NF1-1 and mel-NF1-2 cells. β-actin served as a loading control (n = 1). *P < 0.05, ***P < 0.001, ANOVA followed by Dunnett’s multiple-comparison test with NF1-1 control or NF1-2 control cells (C, D, and F).