MTAP (Methylthioadenosine Phosphorylase): MTAP is an enzyme involved in the methionine salvage pathway, recycling methylthioadenosine produced during polyamine synthesis. It plays a crucial role in nucleotide and polyamine metabolism, supporting cell growth and differentiation. Loss of MTAP is common in various cancers and is associated with poor prognosis, making it a potential therapeutic target due to its significance in metabolic pathways essential for cell survival.