UMPS and neoplasm: Orotate phosphoribosyltransferase (OPRT), an important enzyme catalyzing the synthesis of pyrimidine nucleotides, has been developed as the target for various therapeutic purposes such as tuberculosis (TB), malaria, toxoplasmosis, and tumor (Javaid et al., 1999; Temmink et al., 2007; Abdo et al., 2010; Breda et al., 2012a).