Cytochrome P450 family 2 subfamily C member 8, Cytochrome P450 family 2 subfamily C member 9, and Cytochrome P450 family 2 subfamily C member 19 (CYP2C8, CYP2C9, CYP2C19)

CYP2C8, CYP2C9, and CYP2C19 are closely related but distinct enzymes of the cytochrome P450 superfamily, encoded by separate genes located together on chromosome 10. These hepatic microsomal enzymes are responsible for the oxidative metabolism of a broad range of clinically important drugs and endogenous compounds, accounting for about 20-25% of all cytochrome P450 content in the adult human liver. Each enzyme displays substrate specificity but with some overlap, particularly in the metabolism of nonsteroidal anti-inflammatory drugs, oral hypoglycemics, and chemotherapeutics. All three have highly polymorphic genes, making pharmacogenomic profiling relevant for predicting drug efficacy and risk of adverse effects. Inhibition, induction, or genetic variation in these enzymes is a major source of variability in drug responses and a common mechanism for drug-drug interactions in the clinic.

Other names

Cytochrome P450 2C8Cytochrome P450 2C9Cytochrome P450 2C19(R)-limonene 6-monooxygenase(S)-limonene 6-monooxygenaseCYP2C subfamily

Substrate oxidation (phase I metabolism): drugs are hydroxylated, demethylated, or otherwise oxidized Prodrug activation (e.g., clopidogrel by CYP2C19) Drug inactivation leading to decreased efficacy (e.g., proton pump inhibitors by CYP2C19) Generation of pharmacologically active or toxic metabolites