Oncogenic tyrosine kinases phosphorylate NAMPT at Y188 and turn on NAD+ salvage, including at mitochondria

Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting NAD+ salvage enzyme, is a direct substrate of proto-oncogenic tyrosine kinases (ALK, insulin receptor, IGF1R, PDGFRA). Phosphoproteomics name Y188 as the major site, including on the fusion kinase NPM1::ALK. NAMPT meets NPM1::ALK in cytoplasm, nucleus, and mitochondria. Y188 phosphorylation raises catalytic activity, nicotinamide mononucleotide (NMN)/NAD+ biosynthesis, and downstream metabolism. A Y188F mutant or a dimerization break weakens enzyme, proliferation, and clonogenicity. NAMPT inhibition hits ALK-inhibitor-sensitive and -resistant lymphoma and pairs with ALK blockade.

Finding. Oncogenic tyrosine kinases turn on NAD+ salvage by phosphorylating NAMPT at tyrosine 188. ALK, insulin receptor, IGF1R, and PDGFRA all do it. The fusion kinase NPM1::ALK meets NAMPT in the cytoplasm, the nucleus, and mitochondria. Phosphorylation makes the enzyme faster, raises NMN and NAD+, and feeds downstream metabolism. A Y188F mutant or a broken dimer does the reverse: less activity, less growth, fewer colonies. Phosphorylated dimers sit with metabolic and redox partners; monomers sit with ribosome-biogenesis partners. NAMPT drugs still hurt ALK-inhibitor-resistant lymphoma and help ALK drugs.

Why this paper matters

NAMPT inhibitors have been in oncology for years as a blunt NAD+ starve. This paper gives the enzyme a kinase switch. If Y188 is how ALK and growth-factor receptors raise salvage activity, then NAD+ supply is an acute oncogene output, including at mitochondria, not only a transcriptional addiction.

The three-compartment interaction matters. A mitochondrial NAMPT–ALK pair is a local NAD+ hypothesis for OXPHOS and redox enzymes that run on that cofactor. The paper does not prove compartmental NAD+ pools. It puts the two proteins in the same organelle.

What they actually measured

Phosphoproteomics (Y188 major). Kinase list. Co-localization/interaction in cytoplasm, nucleus, mitochondria. Activity, NMN/NAD+, metabolism. Y188F and dimerization genetics. Interactomes split by phospho-dimer versus monomer. NAMPT inhibition in ALK-sensitive and ALK-resistant lymphoma, plus combination with ALK blockade.

The cooperative claim is phosphorylation plus dimerization. Lose either and the machine fails. That is a clean two-input model.

How to read the score

High seventies. Residue, organelle locale, metabolic output, and a resistant-lymphoma hook. Confidence is medium. Score 78.

What to do with it

Track if you work on NAD+ salvage, ALK fusions, or mitochondrial NAD+ in cancer. Pull the Y188 phosphomap and the mitochondrial interaction data. Do not treat NAMPT inhibition as newly justified monotherapy; the brief says it can pair with ALK blockade and still hit resistant cells. The directional implication is that tyrosine-kinase tumors can phosphorylate NAMPT to raise NAD+, including where NAMPT meets ALK on mitochondria.

Source preprint

Tyrosine phosphorylation and dimerization cooperatively activate NAMPT to enable NAD+ synthesis in cancer

10.64898/2026.08.13.744642

Basappa J, Lobello C, Faustino AM, Uribe-Alvarez C, Rushmore D, Sen N, Wang L, Efimov A, Cai KQ, Schneider JL, Rink L, Hata AN, Mologni L, Zhang W, Goldman AR, Tang H, Nejati R, Dunbrack R, Chernoff J, Baur JA, Wasik MA.