Establishment of a human hepatoma cell line, HLE/2E1, suitable for detection of p450 2E1-related cytotoxicity.
By transfection of an expression vector of human cytochrome P450 2E1 (CYP2E1) into a human hepatoma cell line (HLE), a new cell line (HLE/2E1) that stably expresses activity of CYP2E1 has been established. The HLE/2E1 cell line expressed a higher level of CYP2E1 messenger ribonucleic acid than did the mother HLE cell line. CYP2E1 enzyme activity determined by a p-nitrophenol oxidation assay was also higher in HLE/2E1 cells than in HLE cells. In addition, the enzyme activity of the HLE/2E1 cells was increased by ethanol treatment. Exposure to acetaminophen (APAP) or buthionine sulfoximine (BSO) caused a greater decrease in viability of the HLE/2E1 cells than that of the HLE cells, as determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. The cytotoxicity of APAP or BSO to HLE/2EI cells was inhibited by the addition of ethanol or vitamin E. However, the cytotoxicity of both APAP and BSO was enhanced by 24-h preincubation of HLE/2E1 cells with ethanol. These results show that this cell line provides a useful model for studying catalytic properties of CYP2E1 and cytotoxic mechanisms of chemicals metabolized by CYP2E1.
Nozaki
I
I
Department of Cell Biology, Institute of Cellular and Molecular Biology, Okayama University Medical School, Japan.
Tsuji
T
T
Sakaguchi
M
M
Inoue
Y
Y
Hirai
R
R
Andou
A
A
Miyazaki
M
M
Shimizu
N
N
Namba
M
M
D000082:Acetaminophen / Q000494:pharmacology; D019328:Buthionine Sulfoximine / Q000494:pharmacology; D006528:Carcinoma, Hepatocellular; D002455:Cell Division; D002461:Cell Line, Transformed; D002470:Cell Survival / Q000187:drug effects; D019392:Cytochrome P-450 CYP2E1 / Q000235:genetics / Q000378:metabolism*; D000431:Ethanol / Q000494:pharmacology; D015870:Gene Expression; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D014407:Tumor Cells, Cultured
D000082:Acetaminophen; D000431:Ethanol; D019328:Buthionine Sulfoximine; D019392:Cytochrome P-450 CYP2E1