Updated publication reference for DOI(s): 10.3389/fphar.2021.769703. Cytochrome P450 oxidoreductase (POR) is involved in the oxidative metabolism of xenobiotics and endogenous compounds like fatty acid and cholesterol. While effects of diminished Por were extensively studied in mouse models, studies in human models are still missing. We used previously established CRISPR/Cas9-mediated POR knockdown in HepaRG cells as a human hepatic cell model to investigate the effects of POR knockdown on global protein expression levels.