Cytochrome P450 2B1 (CYP2B1) (CYP2B1)

Cytochrome P450 2B1 (CYP2B1) is a rat-derived heme-containing enzyme that plays a critical role in the oxidative metabolism of xenobiotics and endogenous lipids (UniProt P00185). In the context of biotechnology and cancer therapy, it is frequently employed in Gene-Directed Enzyme Prodrug Therapy (GDEPT) systems, such as those utilizing encapsulated HEK293 cells (PubMed: 12167605). This therapeutic strategy involves the microencapsulation of CYP2B1-expressing cells in polymers like cellulose sulfate, which are then implanted near a tumor site. The encapsulated cells act as a bioreactor that locally activates systemic prodrugs, specifically the oxazaphosphorines cyclophosphamide and ifosfamide, into their active cytotoxic forms (PubMed: 10529798). This localized conversion significantly enhances the therapeutic index of the chemotherapy by concentrating the active drug within the tumor while sparing healthy tissues from systemic exposure. The use of encapsulated HEK293 cells provides a protective environment that prevents immune-mediated destruction of the non-autologous cells, allowing for prolonged enzymatic activity in vivo.

Other names

Cytochrome P450 IIB1Phenobarbital-inducible cytochrome P450CYPIIB1CypCapsEncapsulated CYP2B1-HEK293 cells

CYP2B1 catalyzes the 4-hydroxylation of oxazaphosphorine prodrugs, such as cyclophosphamide and ifosfamide, into cytotoxic metabolites like phosphoramide mustard and acrolein, which induce DNA cross-linking and cell death.