Nicotinamide N-methyltransferase (NNMT): A key enzyme in cancer metabolism and therapeutic target

Emerging research has positioned Nicotinamide N-methyltransferase (NNMT) as a key player in oncology, with its heightened expression frequently observed across diverse cancers. This increased presence is tightly linked to tumor initiation, proliferation, and metastasis. The enzymatic function of NNMT is centered on the methylation of nicotinamide (NAM), utilizing S-adenosylmethionine (SAM) as the methyl donor, which results in the generation of S-adenosyl-L-homocysteine (SAH) and methyl nicotinamide (MNAM). This metabolic process reduces the availability of NAM, necessary for Nicotinamide adenine dinucleotide (NAD