Effects of dietary sinigrin or indole-3-carbinol on O6-methylguanine-DNA-transmethylase activity and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced DNA methylation and tumorigenicity in F344 rats. 1988

M A Morse, and C X Wang, and S G Amin, and S S Hecht, and F L Chung
Division of Chemical Carcinogenesis, American Health Foundation, Valhalla, NY 10595.

The effects of dietary sinigrin and indole-3-carbinol (I3C) on DNA methylation and O6-methylguanine--DNA-transmethylase activity, factors which may be of importance in the induction of tumorigenicity by the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), were investigated. Additionally, the effects of dietary sinigrin on NNK tumorigenicity were assessed in a two-year bioassay in F344 rats. DNA methylation in target tissues of NNK tumorigenesis was examined in F344 rats administered [3H-CH3]NNK (0.6 mg/kg, four doses) s.c. and fed control or experimental diets for two weeks. Dietary sinigrin at a concentration of 3 mumol/g diet decreased 7-methylguanine formation in hepatic DNA, but had no effect on 7-methylguanine levels of lung or nasal mucosa DNA. Dietary I3C at a concentration of 30 mumol/g diet increased 7-methylguanine levels in hepatic DNA, but decreased DNA methylation in lung and nasal mucosa. No effects on O6-methylguanine--DNA-transmethylase activity were observed in tissue extracts derived from the livers, lungs and nasal mucosae of rats fed diets containing sinigrin or I3C. These results suggested that dietary sinigrin might reduce the incidence of NNK-induced hepatic tumors with no effect on NNK tumorigenesis of the lung and nasal cavity, whereas I3C might increase hepatic tumor incidence and reduce NNK tumorigenesis of the lung and nasal cavity. The bioassay results showed that dietary sinigrin had no effect on NNK tumorigenesis in these target tissues. However, dietary sinigrin plus NNK resulted in a significant incidence of pancreatic tumors, a rare occurrence in F344 rats. While the results from DNA methylation studies are in agreement with the bioassay data for lung and nasal cavity, the absence of any inhibitory effect of dietary sinigrin on NNK hepatic tumorigenesis indicates that factors other than DNA methylation and O6-methylguanine repair should be considered in assessing the effects of dietary compounds on NNK hepatic tumorigenesis. The contrary effects on NNK-induced hepatic DNA methylation by sinigrin and I3C, two major components of cruciferous vegetables, demonstrate the complexities of dietary modulation of carcinogenesis.

UI MeSH Term Description Entries
D007211 Indoles Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.
D008113 Liver Neoplasms Tumors or cancer of the LIVER. Cancer of Liver,Hepatic Cancer,Liver Cancer,Cancer of the Liver,Cancer, Hepatocellular,Hepatic Neoplasms,Hepatocellular Cancer,Neoplasms, Hepatic,Neoplasms, Liver,Cancer, Hepatic,Cancer, Liver,Cancers, Hepatic,Cancers, Hepatocellular,Cancers, Liver,Hepatic Cancers,Hepatic Neoplasm,Hepatocellular Cancers,Liver Cancers,Liver Neoplasm,Neoplasm, Hepatic,Neoplasm, Liver
D008175 Lung Neoplasms Tumors or cancer of the LUNG. Cancer of Lung,Lung Cancer,Pulmonary Cancer,Pulmonary Neoplasms,Cancer of the Lung,Neoplasms, Lung,Neoplasms, Pulmonary,Cancer, Lung,Cancer, Pulmonary,Cancers, Lung,Cancers, Pulmonary,Lung Cancers,Lung Neoplasm,Neoplasm, Lung,Neoplasm, Pulmonary,Pulmonary Cancers,Pulmonary Neoplasm
D008297 Male Males
D008745 Methylation Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed) Methylations
D008780 Methyltransferases A subclass of enzymes of the transferase class that catalyze the transfer of a methyl group from one compound to another. (Dorland, 28th ed) EC 2.1.1. Methyltransferase
D009374 Neoplasms, Experimental Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms. Experimental Neoplasms,Experimental Neoplasm,Neoplasm, Experimental
D009602 Nitrosamines A class of compounds that contain a -NH2 and a -NO radical. Many members of this group have carcinogenic and mutagenic properties. Nitrosamine
D009669 Nose Neoplasms Tumors or cancer of the NOSE. Cancer of Nose,Nasal Neoplasms,Nose Cancer,Cancer of the Nose,Nasal Cancer,Neoplasms, Nose,Cancer, Nasal,Cancer, Nose,Cancers, Nasal,Cancers, Nose,Nasal Cancers,Nasal Neoplasm,Neoplasm, Nasal,Neoplasm, Nose,Neoplasms, Nasal,Nose Cancers,Nose Neoplasm
D010190 Pancreatic Neoplasms Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA). Cancer of Pancreas,Pancreatic Cancer,Cancer of the Pancreas,Neoplasms, Pancreatic,Pancreas Cancer,Pancreas Neoplasms,Pancreatic Acinar Carcinoma,Pancreatic Carcinoma,Acinar Carcinoma, Pancreatic,Acinar Carcinomas, Pancreatic,Cancer, Pancreas,Cancer, Pancreatic,Cancers, Pancreas,Cancers, Pancreatic,Carcinoma, Pancreatic,Carcinoma, Pancreatic Acinar,Carcinomas, Pancreatic,Carcinomas, Pancreatic Acinar,Neoplasm, Pancreas,Neoplasm, Pancreatic,Neoplasms, Pancreas,Pancreas Cancers,Pancreas Neoplasm,Pancreatic Acinar Carcinomas,Pancreatic Cancers,Pancreatic Carcinomas,Pancreatic Neoplasm

Related Publications

M A Morse, and C X Wang, and S G Amin, and S S Hecht, and F L Chung
February 1986, Cancer research,
M A Morse, and C X Wang, and S G Amin, and S S Hecht, and F L Chung
February 1987, Carcinogenesis,
M A Morse, and C X Wang, and S G Amin, and S S Hecht, and F L Chung
July 1997, Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology,
M A Morse, and C X Wang, and S G Amin, and S S Hecht, and F L Chung
January 1984, IARC scientific publications,
Copied contents to your clipboard!