fumaric-acid and Lung-Neoplasms

Four agents, fumaric acid (FA), N-acetylcysteine (NAC), N-(4-hydroxyphenyl) retinamide (4-HPR) and beta-carotene (beta-CT), were evaluated for potential chemopreventive activity using the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumor model in female A/J mice. The agents were evaluated in both 16-week and 52-week bioassays at two dose levels corresponding to 0.8 maximum tolerated dose (MTD) and 0.4 MTD administered throughout the bioassay either in the diet (FA, 160 and 80 mmol/kg diet; NAC, 160 and 80 mmol/kg diet; 4-HPR, 4 and 2 mmol/kg diet) or by subcutaneous injection twice a week (beta-CT, 32 and 16 mg/kg b.w.). Mice were treated with a single i.p. dose of 10 micromol NNK in saline 1 week after administration of test agent. Lung adenomas were evaluated in the 16-week bioassay, whereas both adenomas and adenocarcinomas of the lung were determined in the 52-week bioassay. Both bioassays showed that all four agents did not significantly inhibit the total tumor incidence and multiplicity of the lung. However, the incidence of adenocarcinomas was reduced (P < 0.01) at 52 weeks in NNK groups given either 0.8 MTD NAC or 0.8 MTD beta-CT compared with the NNK control group. The decreases in adenocarcinomas were accompanied by corresponding increases in adenomas in these treatment groups. Thus, this study showed that FA, NAC, 4-HPR and beta-CT did not inhibit the total tumor formation, however, at the higher doses both NAC and beta-CT significantly retarded the malignant progression in the lung of NNK-treated A/J mice.

Topics: Acetylcysteine; Animals; Anticarcinogenic Agents; beta Carotene; Carcinogens; Dose-Response Relationship, Drug; Female; Fenretinide; Fumarates; Lung Neoplasms; Mice; Mice, Inbred A; Nicotiana; Nitrosamines; Plants, Toxic

The inhibitory effect of fumaric acid (FA) on carcinogenesis by potassium 1-methyl-7-[2-(5-nitro-2-furyl)vinyl]-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxylate (trans, NFN) was examined histologically with male ICR/JCL mice. NFN was fed to mice at a dose level of 0.012% in the diet for 14 weeks. These mice were then divided into 2 groups. One group was given a basal diet, and the other group was given a diet containing 1% FA in the subsequent 39 weeks. In the group of 30 mice fed NFN alone, squamous cell carcinomas were found in the stomachs of 7 mice, multiple papillomas in the stomachs of 13 mice, and multiple and large papillary adenocarcinomas in the lungs of 27 animals. The administration of FA suppressed the NFN-induced stomach and lung carcinogenesis. In the group of 32 mice fed NFN and FA, no stomach tumors developed except 1 early-stage of squamous cell carcinoma. In the lungs, only a small focus of mild atypical hyperplasia and a few early-stage adenocarcinomas were noted in 7 and 11 animals, respectively.

Topics: Adenocarcinoma; Animals; Carcinoma, Squamous Cell; Drug Interactions; Fumarates; Lung Neoplasms; Mice; Mice, Inbred ICR; Nalidixic Acid; Papilloma; Stomach Neoplasms