Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Vitamin A level and the cytosol-binding proteins specific for vitamin A ere studied in human tumor and its surrounding tissue. The tissues examined were 10 hepatocellular carcinomas which were surgically removed, 4 other malignant tumors (2 metastatic liver cancer and one each of gastric cancer and glioma), and 3 human fetal livers. Compared with surrounding tissues, considerable decrease of vitamin A content was observed in the hepatocellular carcinoma suggesting local deficient state of the vitamin. In addition to cellular retinol-binding protein (CRBP) and retinoic acid-binding protein (CRABP), a new molecular species having affinity for both retinol and retinoic acid was detected in the cytosols obtained from hepatocellular carcinoma as well as glioma by means of gel filtration on Sephadex G-75. With regard to ligand specificity, the protein was found to be similar to cellular retinol-binding protein, F-type or CRBP(F) which was originally recognized in the fish eye cytosol. Since the protein was also demonstrated in human fetal liver, CRBP(F) is considered to be an oncofetal protein in nature. The present study further revealed that CRBP(F) was detected in 80% of hepatocellular carcinoma (whereas plasma alpha-fetoprotein was significantly elevated only in 50%), and hepatocellular carcinoma contained CRBP(F) in a larger amount than CRABP.
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PMID:Demonstration of a novel cellular retinol-binding protein, F-type, in hepatocellular carcinoma. 8 58

A new and sensitive assay procedure for studying erythrophagocytosis is described. The assay technique permits quantitation of the in vivo and in vitro effects of chemicals, hormones, and cell, or microbrial products, on the level of phagocytic activation of glass-adherent cells. The effect of intraperitoneal injection of BCG, Zymosan, Vitamin A, B. pertussis, cortisone, estrone, and thioglycollate on phagocytic activation of peritoneal exudate cells harvested from two days up to 28 days following drug injection was examined by this assay. Erythrophagocytosis was compared to the effect of "activated" spleen cells on tritiated thymidine uptake of a tumor target cell suspension.
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PMID:A sensitive and reproducible assay for the quantitation of erythrophagocytosis and its correlation with reduction in tritiated thymidine uptake in a tumor target cell system modified by immunoenhancing or immunosuppressive agents. 18 42

The anti-tumor effect of vitamin A and/or BCG was investigated in Lewis lung tumor system. Tumor growth and lung metastases were significantly suppressed, when tumor cells were mixed with BCG and inoculated subcutaneously into vitamin A-treated animals. Survival time was also prolonged by the same treatment. Vitamin A alone, without BCG, showed no effect on tumor growth, lung metastases or survival time.
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PMID:[Inhibition of tumor growth and metastases in mice with Lewis lung tumors by vitamin A and BCG]. 36 77

The anti-tumor effect of vitamin A and/or BCG was investigated in Lewis lung tumor system. Tumor growth and lung metastases were significantly suppressed, when tumor cells were mixed with BCG and inoculated subcutaneously into vitamin A-treated animals. Survival time was also prolonged by the same treatment. Vitamin A alone, without BCG, showed no effect on tumour growth, lung metastases or survival time.
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PMID:Suppressed tumor growth and metastasis by vitamin A + BCG in Lewis lung tumor bearing mice. 91 54

Vitamin A palmitate was incorporated into a laboratory chow (150,000 IU/kg diet) and fed ad libitum to C3H/HeJ female mice inoculated with 1 times 10-6 C3HBA tumor cells, beginning the day of inoculation. Control female mice of the same strain similarly inoculated were fed the laboratory chow alone. Vitamin A did not affect rate for the first 19 days, after which growth rates were independent of treatment. Vitamin A-treated mice survived for significantly longer times than did control mice.
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PMID:Antitumor action of vitamin A in mice inoculated with adenocarcinoma cells. 113 55

We studied the influence of the vitamins retinol acetate, alpha-tocopherol acetate and thiamine chloride; the antioxidant sodium selenite and an inhibitor of polyamine biosynthesis, alpha-difluoromethylornithine, on the offspring of transplacental carcinogenesis by ethylnitrosourea in rats. Ethylnitrosourea was given to pregnant rats as a single i.v. injection, at a dose of 75 mg/kg body wt. or 5.5 mg/kg body wt., on the 21st day after conception. Retinol, tocopherol or thiamine was added to the diet, and selenite and alpha-difluoromethylornithine to drinking water of the offspring throughout their postnatal life at moderate doses. In control groups, ethylnitrosourea induced tumors of brain, spinal cord, peripheral nervous system and kidneys in the offspring. alpha-Difluoromethylornithine exerted a slight inhibitory effect; this agent decreased the total tumor multiplicity and the multiplicity of peripheral nervous system tumors and also prolonged survival time. Retinol, tocopherol, thiamine and selenite did not influence the development of the transplacentally-induced tumors.
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PMID:Study of postnatal effects of chemopreventive agents on offspring of ethylnitrosourea-induced transplacental carcinogenesis in rats. I. Influence of retinol acetate, alpha-tocopherol acetate, thiamine chloride, sodium selenite, and alpha-difluoromethylornithine. 165 70

An in vitro assay was designed to examine and quantitate the action of chemical promoters and chemopreventive agents on papillomavirus DNA-carrying cells. Cultured C3H/10T1/2 cells transfected with bovine papillomavirus type 1 DNA (plasmid pdBPV-1) were used as targets, and the frequency of transformed foci was used as an endpoint. The development of foci with a transformed phenotype was greatly enhanced by tumor promoters (e.g., mezerein, 12-O-tetradecanoyl-phorbol-13-acetate, teleocidin, and okadaic acid) and complex mixtures such as extracts of the areca nut, which is an integral part of a betel quid and is linked to oral cancers among chewers. The degree of promotion depended on the length of exposure, the type of promoter, and the time of application after transfection with BPV DNA. The inhibitory effect of chemopreventive agents on transformation can be tested either directly on BPV DNA transfected cells (promoter-independent transformation), or on transfected cells that were exposed to tumor promoters (promoter-dependent transformation). Retinol, and to a lesser degree beta-carotene, exerted an inhibitory effect on promoter-dependent and promoter-independent transformation of BPV DNA transfected cells. The inhibitory effect was conveyed either by the addition of retinol simultaneously with promoters, or after exposure to the promoting agents was completed. The significance of this short-term in vitro assay for the design of chemopreventive trials is discussed.
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PMID:Cell transformation induced by bovine papillomavirus DNA as an assay for tumor promoters and chemopreventive agents. 166 Dec 4

Painting and feeding of mice with 2mg of an extract from black pepper on 3 days a week for 3 months results in a significant increase of the number of tumor-bearing mice. Tumor incidence is reduced in those groups of experimental animals receiving 5 or 10mg Vitamin A-palmitate twice weekly for 3 months by feeding or painting during and subsequent to application of pepper extract. Feeding of mice with powder of black pepper in diet (50g/3kg food) has no impact on carcinogenesis.
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PMID:Carcinogenesis induced by black pepper (Piper nigrum) and modulated by vitamin A. 209 70

The pattern of changes in the polyamine spectrum has been studied under the stress of Sarcoma 180, a transplanted tumor growing in the peritoneal cavity of mice. Retinol, a known inhibitor of ornithine decarboxylase, was used to modulate tumor growth pattern and subsequent changes in the level of polyamines. The polyamine levels showed an increase during tumor proliferation. In the treated group, however, the enhanced levels exhibited a tendency to decrease, along with tumor inhibition, indicating that a positive correlation exists between the polyamine content in the red blood cells of mice and the tumor growth pattern.
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PMID:The role of polyamines as a marker of tumor progression and regression in experimental tumors. 223 13

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


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