NAPRT and cancer: This deferent dependence renders cancer cells resistant to inhibition of NAMPT by other NAD+ synthesis.408 In line with this hypothesis, the loss of NAPRT in both RCC cell lines and EMT-subtype gastric cell lines renders the cells hypersensitive to NAMPT inhibitors, such as FK866, and KPT-9274, suggesting that NAMPT inhibitors may be a promising strategy for NAPRT deficient tumors.421,423 Moreover, bacteria-mediated deamidated NAD+ biosynthesis also rescues NAMPTi-induced toxicity in cancer cells and xenograft tumors.101