Role of nitric oxide in human gastric cancer cells treated with 5-fluorouracil.
We examined whether 5-fluorouracil (5-FU) induces nitric oxide (NO) production and evaluated the role of NO in antitumor activity in human gastric cancer cells. MKN-1 gastric cancer cells were treated with the IC50 of 5-FU in the presence of interferon-gamma (IFN-gamma). In addition, s-methylisothiourea (an antagonist of inducible nitric oxide synthase) or anti-TNF-alpha antibody was added to the culture medium. Production of NO was measured by nitrite assay, TNF-alpha was measured by enzyme-linked immunoabsorbent assay, antitumor activity was evaluated by 3-[4,5-dimethylethiazol-2-yl]-2,5-dipheniltetrasolium bromide (MTT) assay. After 5-FU treatment in the presence of IFN-gamma, NO and TNF-alpha were produced and anti-tumor activity was enhanced. In contrast, s-methylisothiourea abolished the antitumor activity of 5-FU treatment. Anti-TNF-alpha antibody inhibited NO production and decreased the antitumor activity. 5-FU induces NO production by gastric cancer cells, and NO participates in antitumor activity in gastric cancer cells. These effects may be mediated by TNF-alpha production.
Oshima
T
T
First Department of Surgery, Yokohama City University, School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama City, Kanagawa-ken 236-0004, Japan. oshimat@d2.dion.ne.jp
Imada
T
T
Nagashima
Y
Y
Cho
H
H
Shiozawa
M
M
Rino
Y
Y
Takanashi
Y
Y
D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D005472:Fluorouracil / Q000494:pharmacology*; D005562:Formazans; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007550:Isothiuronium / Q000031:analogs & derivatives / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D013778:Tetrazolium Salts; D014407:Tumor Cells, Cultured / Q000187:drug effects* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D000964:Antimetabolites, Antineoplastic; D004791:Enzyme Inhibitors; D005562:Formazans; D013778:Tetrazolium Salts; D014409:Tumor Necrosis Factor-alpha; D007550:Isothiuronium; C079782:MTT formazan; D009569:Nitric Oxide; D007371:Interferon-gamma; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C027744:S-methylisothiopseudouronium; D005472:Fluorouracil