OTC and hepatocellular carcinoma: The high expression of CPS1 relative to that of OTC in CRhi HCC observed in our study concurs with global proteomics analysis of tumor and nontumor tissue (40) and has been shown to result in carbamoyl phosphate diversion to the cytosol to enhance CAD activity (5, 29), which is negatively associated with prognosis (41–43).