title: Effects of essential fatty acid deficiency and of carbon tetrachloride-induced liver cirrhosis on oral carcinogenesis in the rat.
abstract: The relative resistance of the oral mucosa to carcinogenic influences was studied in connection with altered fatty acid composition of the oral epithelium in the rat. The water-soluble carcinogen 4-nitrochinoline N-oxide was used. The lipid changes were induced either through essential fatty acid (EFA) deficiency or through carbon tetrachloride-induced liver cirrhosis. Although the strongest initial reaction in the oral mucosa was seen in the EFA-deficient rats, a result considered to be due to increased permeability of the epithelium to the carcinogen, oral carcinoma did not develop earlier in the EFA-deficient group than in normal controls. The liver cirrhotic group developed clinical signs of carcinoma earliest (5.4 months) whereas in EFA-deficient and normal rats carcinoma appeared after an average of 6.0 and 6.5 months, respectively. However, as a previous study (Lekholm 1976) has shown that the fatty acid changes were less pronounced in cirrhotic than in EFA-deficient rats, it would appear that there is no clear correlation between the extent of lipid distrubance and reduced resistance of the oral epithelium to the induction of carcinoma.
mesh_terms: D015112:4-Nitroquinoline-1-oxide / Q000494:pharmacology; D000818:Animals; D002251:Carbon Tetrachloride; D002273:Carcinogens; D004032:Diet; D005228:Fatty Acids, Essential / Q000172:deficiency*; D007568:Jaw / Q000473:pathology; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000139:chemically induced / Q000150:complications*; D008297:Male; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000209:etiology*; D051381:Rats; D014059:Tongue / Q000473:pathology
chemical_list: D002273:Carcinogens; D005228:Fatty Acids, Essential; D015112:4-Nitroquinoline-1-oxide; D002251:Carbon Tetrachloride