Microwave oven-based technique for immunofluorescent staining of paraffin-embedded tissues.

Immunohistochemical analysis of formalin-fixed paraffin-embedded tissues can be challenging due to potential modifications of protein structure by exposure to formalin. Heat-induced antigen retrieval techniques can reverse reactions between formalin and proteins that block antibody recognition. Interactions between antibodies and antigens are further enhanced by microwave irradiation, which has simplified immunohistochemical staining protocols.

Lower induction of p53 and decreased apoptosis in NQO1-null mice lead to increased sensitivity to chemical-induced skin carcinogenesis.

NAD(P)H:quinone oxidoreductase 1 (NQO1) is a cytosolic protein that catalyzes metabolic detoxification of quinones and protects cells against redox cycling and oxidative stress. NQO1-null mice deficient in NQO1 protein showed increased sensitivity to 7,12-dimethylbenz(a)anthracene- and benzo(a)pyrene-induced skin carcinogenesis. In the present studies, we show that benzo(a)pyrene metabolite benzo(a)pyrene-trans-7,8-dihydrodiol-9,10-epoxide and not benzo(a)pyrene quinones contributed to increased benzo(a) pyrene-induced skin tumors in NQO1-null mice.

Presence and induction of the enzyme NAD(P)H: quinone oxidoreductase 1 in the central nervous system.

NAD(P)H:quinone oxidoreductase 1 (NQO1) catalyzes a reductive detoxification that is thought to protect cells against the adverse effects of quinones and related compounds. NQO1 activity is present in all tissues. Absence of the enzyme produces abnormalities in the redox state and seizures, suggesting an important role of the protein in the central nervous system.

Disruption of dihydronicotinamide riboside:quinone oxidoreductase 2 (NQO2) leads to myeloid hyperplasia of bone marrow and decreased sensitivity to menadione toxicity.

Dihydronicotinamide riboside (NRH):quinone oxidoreductase 2 (NQO2) is a flavoenzyme that catalyzes the reductive metabolism of quinones. To examine the in vivo role of NQO2, NQO2-null (NQO2-/-) mice were generated using targeted gene disruption. Mice lacking NQO2 gene expression showed no detectable developmental abnormalities and were indistinguishable from wild-type (NQO2+/+) mice.

Disruption of the NAD(P)H:quinone oxidoreductase 1 (NQO1) gene in mice causes myelogenous hyperplasia.

NAD(P)H:quinone oxidoreductase1 (NQO1) is a cytosolic protein that reduces and detoxifies quinones and their derivatives, thus protecting cells against redox cycling and oxidative stress. Disruption of the NQO1 gene in mice caused myeloid hyperplasia of bone marrow and highly significant increases in blood neutrophils, eosinophils, and basophils. NQO1-null mice also showed a decrease in lymphocytes and WBCs as compared with wild-type mice.