DHODH and neuroblastoma: The mitochondrial membrane protein dihydroorotate dehydrogenase (DHODH) is a key enzyme in pyrimidine synthesis, and MYCN promotes the production of pyrimidine nucleotides by upregulating the expression of DHODH. Knocking down DHODH or using inhibitors such as brequinar and GSK983 can delay the growth of MNA-NB tumors.