Zinc finger nuclease knock-out of NADPH:cytochrome P450 oxidoreductase (POR) in human tumor cell lines demonstrates that hypoxia-activated prodrugs differ in POR dependence.

ABSTRACT: Hypoxia, a ubiquitous feature of tumors, can be exploited by hypoxia-activated prodrugs (HAP) that are substrates for one-electron reduction in the absence of oxygen. NADPH:cytochrome P450 oxidoreductase (POR) is considered one of the major enzymes responsible, based on studies using purified enzyme or forced overexpression in cell lines. To examine the role of POR in HAP activation at endogenous levels of expression, POR knock-outs were generated in HCT116 and SiHa cells by targeted mutation of exon 8 using zinc finger nucleases. Absolute quantitation by proteotypic peptide mass spectrometry of DNA sequence-confirmed multiallelic mutants demonstrated expression of proteins with residual one-electron reductase activity in some clones and identified two (Hko2 from HCT116 and S2ko1 from SiHa

SUBMITTER: Su J 

PROVIDER: S-EPMC3873569 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature