Figure 1From: Constitutive activation of the ERK pathway in melanoma and skin melanocytes in Grey horses Activation of the ERK pathway in melanoma of Grey horses. (A) Double immunofluorescence staining was performed for P-ERK1/2 (green in a1-a2, c1-c2) or total ERK1/2 (green in b1-b2, d1-d2) and a nuclear melanocytic marker, MITF (red in a2, b2, c2, d2) in melanoma tissue sections from non-grey and Grey horses; a3, b3, c3, d3, corresponding bright field images of the sections. Arrows and arrowheads indicate representative cells for the corresponding stains. Scale bar, 10 μm. (B) Quantification of P-ERK1/2 and ERK1/2 immunofluorescent signals in relation to the total number of MITF+ cells in melanoma tissue sections from non-grey (n = 12; dark grey bars) and Grey (n = 19; light grey bars) horses shown as the mean ± s.e. of three independent experiments. ***P <0.001. (C) Western blot analysis of P-ERK1/2 levels in GHM vs. human melanoma cell lines with Q61RRAS (BL), V600EBRAF (Mel-Ho) and WTRAS WTBRAF (M5). (D) Quantification of total ERK1/2-normalized P-ERK1/2 protein levels in the cell lines listed in (C). The mean ± s.e. of three independent Western blots are shown.Back to article page