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

A case-control study was conducted to examine the influence of dietary factors on the risk of developing lung cancer among women who have never smoked cigarettes. This study included 124 cases of histologically confirmed carcinoma of the lung and 263 community-based controls. Dietary data were collected utilizing the reduced version of the National Cancer Institute (Block) food frequency questionnaire. The results of this analysis, adjusted for age, education, and total calories, indicated a strong protective effect associated with total vegetable consumption and intake of carotene. Individuals in the highest quartile of vegetable consumption experienced the greatest decreased risk with an odds ratio (OR) of 0.2, [confidence interval (CI) 0.1-0.5]. The effect of all vegetables combined was greater than that of green and yellow vegetables alone (highest quartile OR 0.4, CI 0.2-0.7). Similarly, the protective effect of total carotene (highest quartile OR 0.3, CI 0.1-0.6) was somewhat greater than that of beta-carotene alone (highest quartile OR 0.4, CI 0.2-0.8). Retinol intake was not associated with a decreased risk of lung cancer in our population. There was an inverse association between lung cancer risk and vitamin C intake, which was not significant, although a statistically significant trend was noted.
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PMID:Dietary intake and risk of lung cancer in women who never smoked. 143 44

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

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

Of 600 carotenoids from natural sources that have been characterized, fewer than 10% serve as precursors of vitamin A. Many dietary carotenoids, both with and without provitamin A activity, are found in the blood and tissues of humans. beta-Carotene, the most nutritionally active carotenoid, comprises 15-30% of total serum carotenoids. Vitamin A is formed primarily by the oxygen-dependent central cleavage of beta-carotene and other provitamin A carotenoids. Several carotenoids show enhancement of the immune response, inhibition of mutagenesis, reduction of induced nuclear damage, and protection from various neoplastic events in cells, tissues, and whole animals. Carotenoids also protect against photo-induced tissue damage. Some carotenoids, including beta-carotene, quench highly reactive singlet oxygen under certain conditions and can block free radical-mediated reactions. In epidemiological studies, the intake of carotenoid-rich fruits and vegetables has been correlated with protection from some forms of cancer, particularly lung cancer. Similarly, serum beta-carotene levels have been associated with a decreased chance of developing lung cancer. It must be stressed, however, that these epidemiological associations do not show cause and effect. In this regard, long-term intervention trials with beta-carotene supplements are in progress. Whatever the results of these trials, carotenoids clearly show biological actions in animals distinct from their function as precursors of vitamin A.
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PMID:Biological actions of carotenoids. 265 56

Nutrition surveys suggest an association between the low intake of vitamin A, beta-carotene and cancer death. The prospective Basel study included as a part of its third investigation (1971-1973) the immediate analysis of all plasma vitamins. 2974 men were evaluated and all cancer deaths registered in a first phase until 1980 (n = 102) and in a second period until 1985 (total n = 204). In the completely analyzed seven years follow up we found a strong inverse relationship for beta-carotene and all cancers, lung cancer and stomach cancer (p less than .01). Vitamin A (p less than .01) and vitamin C (p less than .05) were both on the average lower in subsequent stomach cancer death cases compared to non cases. Vitamin E was lower in death by all cancers and by stomach cancer (p less than .05). The first results of the twelve years follow up confirm the significant association for beta-carotene, vitamin A and C and cancer death.
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PMID:[Vitamins and cancer: results of a Basel study]. 275 Mar 33

Epidemiologic studies of diet and cancer have been facilitated in Hawaii by the multiethnic composition of its population and the consequent heterogeneity in dietary intakes. Studies of migrant populations, particularly the Japanese, have firmly supported the conclusions that environmental factors are of predominant etiologic significance for most major sites of cancer, and that these factors may exert their influences at particular periods of life. Recent observations on Filipino migrants reproduce most of the findings in the Japanese, although they do not show the same abrupt increase in colon cancer rates to the high levels found in Caucasians. Data on dietary intakes in these populations support several of the prevailing hypotheses regarding the etiology of certain gastrointestinal and hormone-dependent cancers. Several case-control studies of diet and cancer have been completed or are ongoing in Hawaii. Some of these have included comparable studies in Japan, but the findings in Hawaii have generally not been reproduced in Japan. Weak associations with dietary fat have been found in Hawaii for breast cancer (particularly in Japanese women) and for prostate cancer (particularly in men greater than or equal to 70 years of age). Vitamin A (especially carotene) has been shown to be inversely associated with lung cancer risk in men, but positively associated with prostate cancer risk in older men. Vitamin C may be inversely related to bladder cancer risk, but has shown no relationship to lung or prostate cancer risk. These and other findings are discussed in terms of future needs for epidemiologic research in this field.
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PMID:Multiethnic studies of diet, nutrition, and cancer in Hawaii. 391

Retinol and retinol-binding protein levels were measured in sera previously obtained, and stored in the frozen state, at multiphasic health checkups from 151 persons subsequently found to have lung cancer (cases) and 302 persons who remained free of cancer (controls). Two controls were matched to each case for sex, skin color, age, date of multiphasic health checkup, and aspects of the smoking habit. Mean levels in cases and controls were, respectively, retinol: 82.17 and 82.37 micrograms/dl (p = 0.93), and retinol-binding protein: 6.04 and 6.00 mg/dl (p = 0.81). Mean differences between cases and controls were, retinol: 0.195 micrograms/dl with 95% confidence limits, -3.91 and 4.30 micrograms/dl; retinol-binding protein: -0.033 mg/dl with 95% confidence limits, -0.31 and 0.24 mg/dl. No significant trend in relative risk of lung cancer was observed when the retinol or retinol-binding protein distribution was divided into quintiles. No significant associations were observed in subgroups based on age, sex, histologic type of cancer, cigarette consumption, or interval between blood drawing and cancer diagnosis. In this large study, retinol and retinol-binding protein levels were not useful in predicting the subsequent development of lung cancer.
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PMID:Serum retinol and retinol-binding protein levels do not predict subsequent lung cancer. 396 62

Serum vitamin A (retinol) level was determined in colon and lung cancer patients. As a control served young healthy people and non cancer hospital patients at the age similar to those with tumors. Vitamin A content in cancer patients was found to be statistically lower as compared to control groups.
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PMID:Vitamin A (retinol) level in colon and lung cancer patient sera. 400 Mar 11

Effect of vitamin A on phagocytic activity and the state of bactericide system involving myeloperoxidase and cationic proteins was studied in neutrophils from peripheric blood of volunteers and of the patients with chronic pneumonia and lung cancer. Vitamin A was administered per os within 1 week at a daily dose of 500,000 IU. In healthy persons vitamin A, not affecting the ability of neutrophils to capture and lyse microbes, activated myeloperoxidase and increased the cationic proteins content. Under conditions of lung cancer the vitamin did not alter any patterns of phagocytosis studied. Vitamin A did not affect the capture and lysis of microbes in chronic pneumonia but increased distinctly the myeloperoxidase activity in neutrophils, impaired during the disease, and normalized partially the content of cationic proteins.
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PMID:[Vitamin A: effect on phagocytosis and neutrophil bactericidal systems under normal conditions and in various pathological states]. 409 Mar 90


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