Fig. 3
From: Combined activation of MAP kinase pathway and β-catenin signaling cause deep penetrating nevi
Secondary CTNNB1 mutations in common acquired nevi with BRAF mutations confer the phenotypic characteristics of deep penetrating nevus. a Clinical presentation of ‘combined DPN’ with common nevus and DPN areas. left A dark papule grew within a pre-existing nevus on the back of a 31-year-old woman. right Dermoscopic image of the tumor. b Histopathological features of a ‘combined DPN’ with common nevus and DPN areas, hematoxylin and safranin (H and S) staining. Melanocytes are enlarged in the DPN portion compared to the common acquired nevi portion. left low power view, scale bar 100 microns. right, high power view, scale bar, 10 microns. c β-catenin immunohistochemistry. left Low power view shows increased cytoplasmic and nuclear β-catenin in DPN melanocytes. In common nevus melanocytes, β-catenin expression is decreased in melanocytes deep within the dermis. right High power view. d Cyclin D1 immunohistochemistry. left Low power view shows increased cytoplasmic and nuclear cyclin D1 expression in the DPN component as compared to the common nevus component
