Targeting metabolic reprogramming in metastatic melanoma: The key role of nicotinamide phosphoribosyltransferase (NAMPT).

Cancer cells rewire their metabolism to support proliferation, growth and survival. In metastatic melanoma the BRAF oncogenic pathway is a master regulator of this process, highlighting the importance of metabolic reprogramming in the pathogenesis of this tumor and offering potential therapeutic approaches. Metabolic adaptation of melanoma cells generally requires increased amounts of NAD+, an essential redox cofactor in cellular metabolism and a signaling molecule. Nicotinamide phosphoribosyltransferase (NAMPT) is the most important NAD+ biosynthetic enzyme in mammalian cells and a direct target of the BRAF oncogenic signaling pathway. These findings suggest that NAMPT is an attractive new therapeutic target, particularly in combination strategies with BRAF or MEK inhibitors. Here we review current knowledge on how oncogenic signaling reprograms metabolism in BRAF-mutated melanoma, and discuss how NAMPT/NAD+ axis contributes to these processes. Lastly, we present evidence supporting a role of NAMPT as a novel therapeutic target in metastatic melanoma.