Figure 3
From: MiR-21: an environmental driver of malignant melanoma?
Working model of exogenous and endogeneous factors that increase exosomal miR-21 signaling in malignant melanoma. The common BRAF(V600E) and NRAS(G12D) mutations in cutaneous melanoma increase miR-21 expression by upregulating AP-1 and STAT3. Keratinocyte-derived exosomal miR-21 induced by UV-irradiation, exosomal miR-21 derived from the systemic circulation induced by dietary and environmental factors as well as obesity- and inflammation-associated exosomal miR-21 may enhance the total burden of miR-21 signaling of melanocytes promoting the transition to the malignant phenotype.