Transfection of human cytochrome P-450 reductase cDNA and its effect on the sensitivity to toxins.
NADPH-cytochrome P-450 reductase (CYPR; EC 1.6.2.4) is an essential enzyme for the catalytic function of cytochromes and is also regarded as being implicated in drug activation. To examine whether CYPR is directly involved in the drug metabolism, a cDNA encoding human CYPR was stably transfected into Chinese hamster ovary cells. Three clonal cell lines were identified which expressed increased levels of CYPR activity (9.3- to 11.2-fold). Western blot analysis indicated that CYPR-transfectant cells contained markedly elevated levels of CYPR protein, while wild-type Chinese hamster ovary cells contained low levels. They showed 1.8- to 3.3-fold higher sensitivity to Adriamycin, 2.1- to 3.0-fold higher sensitivity to mitomycin C, and 2.9- to 4.3-fold higher sensitivity to paraquat than wild-type cells. We also studied other common-use anticancer agents: vinblastine, vincristine, VP-16, and cisplatin, but there were no differences observed in the sensitivity. This report provides the first evidence that transfection of human CYPR into mammalian cells is concerned in the sensitivity to some drugs.
Sawamura
A O
AO
Department of Obstetrics and Gynecology, Nagoya University School of Medicine, Japan.
Aoyama
T
T
Tamakoshi
K
K
Mizuno
K
K
Suganuma
N
N
Kikkawa
F
F
Tomoda
Y
Y
D000818:Animals; D000970:Antineoplastic Agents / Q000493:pharmacokinetics* / Q000494:pharmacology*; D001711:Biotransformation; D015153:Blotting, Western; D016466:CHO Cells / Q000187:drug effects / Q000201:enzymology; D006224:Cricetinae; D018076:DNA, Complementary / Q000235:genetics*; D004317:Doxorubicin / Q000493:pharmacokinetics / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D016685:Mitomycin / Q000493:pharmacokinetics / Q000494:pharmacology; D009251:NADPH-Ferrihemoprotein Reductase / Q000235:genetics* / Q000378:metabolism*; D010269:Paraquat / Q000493:pharmacokinetics / Q000494:pharmacology; D014162:Transfection
D000970:Antineoplastic Agents; D018076:DNA, Complementary; D016685:Mitomycin; D004317:Doxorubicin; D009251:NADPH-Ferrihemoprotein Reductase; D010269:Paraquat