Differential toxicity of mitomycin C and porfiromycin to aerobic and hypoxic Chinese hamster ovary cells overexpressing human NADPH:cytochrome c (P-450) reductase.

Purified NADPH:cytochrome c (P-450) reductase (FpT; NADPH-ferrihemoprotein oxidoreductase, EC 1.6.2.4) can reductively activate mitomycin antibiotics through a one-electron reduction to species that alkylate DNA. To assess the involvement of FpT in the intracellular activation of the mitomycins, transfectants overexpressing a human FpT cDNA were established from a Chinese hamster ovary cell line deficient in dihydrofolate reductase (CHO-K1/dhfr-). The parental cell line was equisensitive to the cytotoxic action of mitomycin C under oxygenated and hypoxic conditions. In contrast, porfiromycin was considerably less cytotoxic to wild-type parental cells than was mitomycin C in air and markedly more cytotoxic under hypoxia. Two FpT-transfected clones were selected that expressed 19- and 27-fold more FpT activity than the parental line. Levels of other oxidoreductases implicated in the activation of the mitomycins were unchanged. Significant increases in sensitivity to mitomycin C and porfiromycin in the two FpT-transfected clones were seen under both oxygenated and hypoxic conditions, with the increases in toxicity being greater under hypoxia than in air. These findings demonstrate that FpT can bioreductively activate the mitomycins in living cells and implicate FpT in the differential aerobic/hypoxic toxicity of the mitomycins.

C.U.C.P. alumni journal.

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Turcia Asiatica: exhibens Natoliam modernam, in suos beglirbegatus divisam, itemque reliquos beglirbegatus, sive gubernationes et Prœfecturas generales, in regionibus Georgiæ, Armeniæ, Mespotamiæ, Syriæ et Arabiæ sitos, una cum Mari Nigro, Mari Azowiensi, Mari di Marmora, et Mari Ægeo, atque adiacentibus Insulis : C. P. S. C. M. = Carte de la Turquie asiatique contenant la Natolie moderne divisée en les beglerbeys &

ex novissimis subsidiis ac relationibus ad normam legitimae proiectionis in usum belli praesentis delineata impensis homannianorum heredum.

Where to look for the law. A catalogue of L.C.P. co.'s books, and a brief subject index of other useful legal text work.

Mode of access: Internet.

Vespae, comoedia ; [gr.] edita et notis Brunckii aliorumgue, ut suis instructa a C.P. Conz.

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The origin & growth of the English colonies and of their system of government; an introduction to Mr. C.P. Lucas's Historical geography of the British colonies.

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消費者価格調査 (C P S)とは何か

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C.C.C.P サウェ-ト社会主義共和国聯邦

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Caroli Ludovici Willdenow ... Florae berolinensis prodromus, secundum systema Linneanum ab illustr. viro ac eq. C. P. Thunbergio emendatum conscriptus.

Mode of access: Internet.

The celebrated case of Col. W. C. P. Breckinridge and Madeline Pollard,

Mode of access: Internet.