Given the high turnover of NAD in cancer cells and the fact that NAMPT is the rate-limiting enzyme in the salvage pathway, inhibitors of this enzyme were first reported as possible anticancer agents by Hasmann et al. in 2003, who presented the first specific nanomolar inhibitor of this enzyme, FK866 (also known as APO866; (Hasmann and Schemainda, 2003). This evidence concerns the gene NAMPT and cancer.