Lack of Association between BRAF Mutation and MAPK ERK Activation in Melanocytic Nevi  Pablo Uribe, Leonardo Andrade, Sergio Gonzalez  Journal of Investigative Dermatology  Volume 126, Issue 1, Pages 161-166 (January 2006) DOI: 10.1038/sj.jid.5700011 Copyright © 2006 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 Phosphorylated ERK1/2 and B-Raf expression in melanocytic lesions by immunohistochemistry. Activated MAPK (a–j) and B-Raf (k–p) immunohistochemistry. (a) Formalin-fixed, paraffin-embedded SK-MEL-28 cells (BRAF V600E mutation) in culture media containing 10% of fetal bovine serum. (b) Cells were cultured in starvation and with a MEK inhibitor (20μM U0126). (c) Melanoma with intense activated MAPK staining. Lymphocytes (black dashed oval) and endothelial cells (red dashed circle) were used as internal negative and positive controls. (d) The higher magnification picture shows nuclear and cytoplasmatic staining. (e, f) Melanomas with positive staining. (g) AN negative for activated MAPK, but endothelium reacts with the antibody (red dashed oval). (h) AN with positive staining for activated MAPK. CN negative (i) and positive (j) for activated ERK1/2. (k) PM with intense and diffuse B-Raf expression. (l) The same melanoma as in (k), but incubated with B-Raf antibody and a 10-fold excess of B-Raf blocking peptide. (m) Melanoma showing intense cytoplasmic staining. (n) Melanoma with intense expression of B-Raf. (o) AN with intense staining in the junctional component. (p) CN showing weak B-Raf expression, greater in the upper dermis. Bar=100μm. Journal of Investigative Dermatology 2006 126, 161-166DOI: (10.1038/sj.jid.5700011) Copyright © 2006 The Society for Investigative Dermatology, Inc Terms and Conditions