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Query: UMLS:C0242379 (lung cancer)
 71,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasma antioxidant vitamins A, C, and E and carotene were measured in a group of 2,974 men participating in the third examination of the prospective Basel Study in 1971-1973. In 1985, the vital status and mortality of all participants were assessed. A total of 204 men had died from cancer, including 68 with bronchus cancer and 37 with gastrointestinal cancer (20 with stomach cancer and 17 with large bowel cancer excluding cancer of the rectum). Overall mortality from cancer was associated with low mean plasma levels of carotene adjusted for cholesterol (p less than 0.01) and of vitamin C (p less than 0.01). Bronchus and stomach cancers were associated with a low mean plasma carotene level (p less than 0.01). Subjects with subsequent stomach cancer also had lower mean vitamin C and lipid-adjusted vitamin A levels than did survivors (p less than 0.05). After calculation of the relative risk using the Cox model with exclusion of mortality during the first 2 years of follow-up, low plasma carotene (below quartile 1) was associated with a significantly increased risk for bronchus cancer (relative risk (RR) = 1.8, p less than 0.05), low plasma levels of carotene and vitamin A with all cancers (RR = 2.47, p less than 0.01), and low plasma retinol in older subjects (greater than age 60 years) with lung cancer (RR = 2.17, p less than 0.05). Low levels of vitamin C increased the risk of stomach cancer (RR = 2.38) and gastrointestinal cancer (RR = 2.46) in older subjects, but only significantly with the inclusion of the first 2 years. The authors conclude that low plasma levels of antioxidant vitamins are associated with an increased risk of subsequent cancer mortality. This effect was stronger in men above age 60 years at blood sampling, and the effect seems to be site-specific.
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PMID:Plasma antioxidant vitamins and subsequent cancer mortality in the 12-year follow-up of the prospective Basel Study. 157 Aug 25

Evidence in humans and laboratory animals supports a cancer-protective effect of vitamin A, but the mechanism remains unclear. While vitamin A deficiency causes squamous metaplasia, and lung cancer patients have lower vitamin A status, their serum vitamin A levels are not indicative of deficiency. We hypothesize that local enzymatic degradation of vitamin A can be induced by exposure to carcinogens such as benzopyrene found in cigarette smoke. This study was designed to determine if benzopyrene exposure depletes tissue vitamin A and whether beta-carotene might prevent the depletion. Weanling male Fischer rats were fed a nutritionally complete purified diet, supplemented with or without benzopyrene at 400 mg/kg feed or beta-carotene at 2 g/kg feed. Vitamin A content of the liver, small intestine, and serum was determined by high-performance liquid chromatography. There was no effect of benzopyrene feeding on serum retinol levels through four weeks. However, there was a decline in tissue retinol in the liver and small intestine by two weeks, with a 30% decline by four weeks (p less than 0.05). In rats fed beta-carotene, there was no effect of benzopyrene on tissue vitamin A level. These results indicate that exposure to benzopyrene induces a local tissue vitamin A depletion despite a vitamin A-sufficient diet and maintenance of serum vitamin A levels. A high intake of beta-carotene prevented the vitamin A depletion effect of benzopyrene exposure. Further studies appear warranted to determine whether some of the adverse effects of environmental carcinogens, as found in cigarette smoke, charcoal-broiled meats, and industrial wastes, might be alleviated by dietary intervention.
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PMID:Exposure to the carcinogen benzopyrene depletes tissue vitamin A: beta-carotene prevents depletion. 203 68

Several factors are known to promote the development of a lung cancer. Smoking, occupation, environment, chronic bronchitis, and scars in the lung are all risk factors. Many studies have stressed the importance of nutrition, in particular vitamins. Vitamin A is necessary for cell differentiation. Retrospective and prospective studies have proven the inverse relation between provitamin A, beta-carotene, and lung cancer of the squamous and oat cell types. Studies in which beta-carotene or natural vitamin A are supplied to smokers, controls, and patients after resection for lung cancer are in progress. The study of other vitamins such as vitamin C and vitamin E has not led to definitive conclusions. The trace element selenium may also exert a beneficial effect.
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PMID:Vitamins and lung cancer. 211 8

In a dozen case-control and cohort studies, high intake of fruits and vegetables containing carotenoids has been associated with a reduced risk of lung cancer. In contrast, little relation has been found between intake of preformed vitamin A and this disease. Although initial studies suggested that persons with lower levels of serum retinol have higher future rates of lung cancer, this idea was not confirmed in subsequent investigations. Prediagnostic levels of beta-carotene in blood, however, have been inversely related with risk of lung cancer. Available data thus strongly support the hypothesis that dietary carotenoids reduce the risk of lung cancer, but the data are also compatible with the possibility that some other factor in these foods is responsible for the lower risk. Even if ultimately shown to be casual, the relation between diet and lung cancer is modest compared with the deleterious effect of cigarette smoking.
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PMID:Vitamin A and lung cancer. 219 82

In a case-control study, serum levels of vitamins E, C, and A, carotenoids, total cholesterol, and retinol-binding protein along with smoking levels were studied on 59 persons newly diagnosed with lung cancer and also on matched hospitalized controls. The relative risk for smoking increased with the number of pack years of cigarettes smoked. Cases had significantly lower serum levels of carotenoids, vitamin E, and total cholesterol. Adjustment for serum cholesterol levels diminished the case-control difference for serum carotenoid levels and reduced the case-control difference for serum vitamin E levels. The results indicate that serum vitamin E may also be associated with lung cancer, possibly to a greater degree than serum retinol (vitamin A) is associated with lung cancer.
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PMID:A case-control study of serum vitamins A, E, and C in lung cancer patients. 221 98

From 1968 to 1977, the association between the level of vitamin A in serum and the subsequent incidence of cancer was examined in a longitudinal study of 36,265 persons initially aged 15-99 years in 25 population groups in Finland. During a mean follow-up of 8 years, 766 cancers were diagnosed. Serum retinol, retinol-binding protein, and beta-carotene levels were measured from frozen serum samples (stored at -20 degrees C) drawn from these persons before the start of follow-up and from 1,419 controls matched for sex, age, and place of residence who did not develop cancer during follow-up. The mean level of serum retinol among the cancer cases was 645 micrograms/liter for men and 587 micrograms/liter for women. The corresponding levels in the controls were 3.3% and 2.8% higher. There was an inverse gradient between serum retinol level and the occurrence of cancer among men. This association was, however, mainly concentrated in the first 2 years of follow-up. The mean level of serum beta-carotene was 72.3 micrograms/liter among male cases and 119.5 micrograms/liter among female cases. The corresponding levels of the controls were 14.0% and 5.5% higher. The differences were particularly clear with regard to lung cancer. These findings suggest that the association between retinol and cancer may be due to preclinical cancer and that there may be an association between beta-carotene and cancer.
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PMID:Serum vitamin A and subsequent risk of cancer: cancer incidence follow-up of the Finnish Mobile Clinic Health Examination Survey. 223

Since the first report of a protective effect of dietary vitamin A on lung cancer risk was issued in 1975, a succession of retrospective (case-control) and prospective (cohort) epidemiological studies have examined the association. Food frequency questionnaires have been used to assess dietary intake of food groups and to generate indices of specific dietary components, in particular retinol and carotene. Serum levels of retinol, carotenoids, and other micronutrients have been determined as well, and related to risk of lung cancer. The dietary studies have been notably consistent, finding an approximate 50% reduction in risk associated with high compared to low consumption of carotene-containing fruits and vegetables. Unresolved issues include gender differences, histological specificity and the interaction with cigarette smoking as well as the role of other possible protective factors found in these foods--indoles, vitamin C, trace minerals. Most studies in which serum beta-carotene was assayed in prospectively collected blood samples have found lower levels of beta-carotene in people who subsequently developed lung cancer. Unlike carotene, blood retinol levels do not reflect dietary intake under normal conditions and, as might be expected, have failed to show a consistent relation with risk of lung cancer. Although epidemiological studies have not strongly supported the role of preformed retinol as a protective agent, animal studies have provided convincing evidence that retinol and synthetic retinoids are protective against epithelial tumours including those of the lung. A number of on-going clinical trials are testing the efficacy of retinol, beta-carotene, synthetic retinoids and alpha-tocopherol for preventing cancer of the lung, especially in high risk groups such as heavy smokers, miners and asbestos workers. It is hoped that these trials will help explain the nature of the observed protective effect of fruit and vegetables.
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PMID:Protective dietary factors and lung cancer. 225 74

A search of the literature using National Library of Medicine databases and individual cancer journal articles yielded over 500 compounds with published chemopreventive activity in animals. From these, an initial 16 agents or agent combinations have been evaluated in the following animal tumor models: mouse skin papillomas/carcinomas induced by 7,12-dimethylbenz(a)anthracene/12-O-tetradecanoylphorbol-13-acetate; rat breast adenocarcinoma induced by N-methyl-N-nitrosourea or 7,12-dimethylbenz(a)anthracene; hamster lung carcinoma induced by N-methyl-N-nitrosourea or diethylnitrosamine; mouse bladder papillary carcinoma induced by N-butyl-N-(4-hydroxybutyl)nitrosamine; and rat and mouse colon cancer induced by azoxymethane/methylazoxymethanol acetate. Some of the most interesting positive results observed include 4-hydroxyphenyl retinamide plus tamoxifen in breast cancer, piroxicam in colon cancer, dimethylfluoroornithine in breast and bladder cancer, oltipraz in lung cancer, dehydroepiandrosterone in colon cancer, and molybdate in bladder cancer. Eighteen human intervention trials in progress are described that involve the following agents: beta-carotene (eight trials). Retinol/retinoic acid (seven trials), vitamins C and E (three trials), 4-hydroxyphenyl retinamide (one trial), piroxicam (one trial), and calcium (one trial). By organ site these studies involve cancer of the lung (six studies), skin (five studies), colon (four studies), breast (one study), and uterine cervix (two studies).
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PMID:Identification of candidate cancer chemopreventive agents and their evaluation in animal models and human clinical trials: a review. 240 15

We conducted a population-based study of diet and lung cancer among the multiethnic population of Hawaii in 1983-1985. We completed interviews for 230 men and 102 women with lung cancer and 597 men and 268 women controls, frequency-matched to the patients by age and sex. A quantitative dietary history assessed the usual intake of foods rich in vitamins A and C and carotenoids. A clear dose-dependent negative association was demonstrated between dietary beta-carotene and lung cancer risk in both sexes. After adjusting for smoking and other covariates, the men in the lowest quartile of beta-carotene intake had an odds ratio of 1.9 (95% confidence interval, 1.1-3.2) compared to those in the highest quartile of intake. The corresponding odds ratio for women was 2.7 (95% confidence interval, 1.2-6.1). No clear association was found for retinol, vitamin C, folic acid, iron, dietary fiber, or fruits. All vegetables, dark green vegetables, cruciferous vegetables, and tomatoes showed stronger inverse associations with risk than beta-carotene. This observation suggests that other constituents of vegetables, such as lutein, lycopene, and indoles, and others, may also protect against lung cancer in humans.
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PMID:Vegetable consumption and lung cancer risk: a population-based case-control study in Hawaii. 254 91

A case-control study involving interviews with 1,249 patients with lung cancer and 1,345 population-based controls was conducted in Shenyang, an industrial city in northeastern China, where mortality rates are high among men and women. Cigarette smoking was found to be the principal cause of lung cancer in this population, accounting for 55% of the lung cancers in males and 37% in females. The attributable risk percentage among females is high compared to elsewhere in China, largely because of a higher prevalence of smoking among women. After adjustment for smoking, there were also significant increases in lung cancer risk associated with several measures of exposure to air pollutants. Risks were twice as high among those who reported smoky outdoor environments, and increased in proportion to years of sleeping on beds heated by coal-burning stoves (kang), and to an overall index of indoor air pollution. Threefold increases in lung cancer risk were found among men who worked in the nonferrous smelting industry, where heavy exposures to inorganic arsenic have been reported. The associations with both smoking and indoor air pollution were stronger for squamous cell and small cell carcinomas than for adenocarcinoma of the lung. Risks due to smoking or air pollution were not greatly altered by adjustment for consumption of fresh vegetables or sources of beta carotene or retinol, prior chronic lung diseases, or education level. The findings suggest that smoking and environmental pollution combine to account for the elevated rates of lung cancer mortality in Shenyang.
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PMID:Smoking, air pollution, and the high rates of lung cancer in Shenyang, China. 255 31


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