Cdc25 dual-specificity phosphatases coordinate cell cycle progression and cellular signaling. Consequently, Cdc25 inhibitors represent potential anticancer agents. We evaluated >10,000 compounds for inhibition of human Cdc25 phosphatases and identified many potent and selective inhibitors, which all contained a quinone. Bioreductive enzymes frequently detoxify or activate quinones. Therefore, w...

The anticarcinogenic effect of rosemary has been partly attributed to the modulation of the activity and expression of phase II detoxification enzymes. Here we compared the effects of phenolic diterpenes from rosemary on the expression of NAD(P)H: quinone oxidoreductase 1 (NQO1) in rat Clone 9 liver cells. Cells were treated with 1-20 μmol/L of carnosic acid (CA) or carnosol (CS) for 24 h. Both...

UNLABELLED The role of genetic polymorphisms of NAD(P)H quinone oxidoreductase 1 (NQO1), which is known to be related to carcinogen metabolism and oxidative status, was evaluated for lung cancer development. The genotypes of two NQO1 polymorphisms, namely, IVS1-27C>G and Ex6+40C>T, were determined in 616 lung cancer cases and 616 lung cancer-free controls and haplotypes composed of the two po...

NAD(P)H:quinone oxidoreductase (NQO1, DT-diaphorase) is an enzyme involved in both the detoxification and activation of a variety of substrates (1). This obligate two-electron reductase has chemoprotective properties including reduction of quinone to hydroquinone forms (1, 2), allowing avoidance of semiquinone free radical production and subsequent oxidative damage, as well as metabolism of vit...

NAD(P)H:quinone oxidoreductase 1 / (NQO1 / ), NQO1 along with NRH:quinone oxidoreductase 2 / (NQO2 / ), and wild-type (WT) mice were exposed to five once weekly doses of mitomycin C. The mice were euthanized 15 weeks after the first dose. Blood cell counts and histologic analyses were done. WT and NQO2 / mice showed hypocellularity and a significant increase in adipocytes in bone marrow. They a...

NAD(P)H:quinone oxidoreductase 1 (NQO1) catalyses the reduction of quinoid compounds to hydroquinones, preventing the generation of free radicals and reactive oxygen. A "C" to "T" transversion at position 609 of NQO1, leading to a nonsynonymous amino acid change (Pro187Ser, P187S), results in an altered enzyme activity. No NQO1 protein activity was detected in NQO1(609)TT genotype, and low to i...

Recently, we demonstrated the ability of heavy metals, particularly, Hg 2+ , Pb 2+ , and Cu 2+ to differentially modulate in Hepa 1c1c7 cells the expression of the phase II xenobiotic metabolizing enzymes, Nqo1 and Gst ya genes, yet the mechanisms involved remain unknown. To investigate the molecular mechanisms involved in the regulation of Nqo1 and Gst ya genes by heavy metals, Hepa 1c1c7 cell...

NAD(P)H:quinone oxidoreductase (NQO1) is a flavoenzyme that catalyzes the two-electron reduction of quinones and related compounds. With the use of biochemical assays, NQO1 has been shown to be overexpressed in many types of cancer, including non-small cell lung cancer (NSCLC). NQO1 can bioactlvate antitumor qulnones such as mitomycm C, and new qwnone-based drugs are currently being developed t...

PURPOSE NAD(P)H:Quinone Oxidoreductase 1 (NQO1) C609T missense variant (NQO1*2) and 29 basepair (bp)-insertion/deletion (I29/D) polymorphism of the NRH:Quinone Oxidoreductase 2 (NQO2) gene promoter have been proposed as predictive and prognostic factors for cancer development and progression. The purpose of this study is to investigate the relationship between NQO1/NQO2 genotype and clinico-pat...

NAD(P)H:quinone oxidoreductase (NQO1, DT-diaphorase) is an enzyme involved in both the detoxification and activation of a variety of substrates (1). This obligate two-electron reductase has chemoprotective properties including reduction of quinone to hydroquinone forms (1, 2), allowing avoidance of semiquinone free radical production and subsequent oxidative damage, as well as metabolism of vit...