Aberrant expression of CPS1 in tumors that originate in tissues that normally do not express the gene has been associated with an increased cytoplasmic supply of carbamylphosphate (CP), a substrate of the CAD complex, leading to increased de novo pyrimidine biosynthesis, tumor cell proliferation, and unfavorable patient outcomes [31,32,33,34,35]. The gene discussed is CPS1; the disease is neoplasm.