Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: DrugBank:EXPT00568 (ascorbate)
 23,072 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Malignant cystosarcoma phylloides (CP) is a relatively rare cancer of the breast. A CP tumor was processed as part of a tumor acquisition, propagation, and preservation program in patient biotherapy. Two tissue culture cell lines were developed from this tumor, one directly from the biopsy, another from a xenograft tumor grown in athymic mice. The two cell lines were similar in character. There was strong immunochemical reactivity with antibodies to vimentin, type I collagen, and type III collagen. There was no reactivity with antibodies to cytokeratin and epithelial membrane antigen. Both cell lines were aneuploid, clonogenic in soft agar, and tumorigenic in nude mice. 5 alpha-dihydrotestosterone and thyroxine added to the culture medium stimulated growth, while testosterone, 17 beta-estradiol, and 4-hydroxytamoxifen were without effect. Dexamethasone and cortisol were inhibitory at high doses (10(-6) M). Dibutyryl cyclic AMP, theophylline, and vitamin C were all inhibitory. The biopsy contained tumor-infiltrating lymphocytes which proliferated in cultures containing interleukin 2. The expanded lymphocytes were activated T cells which had the capacity to lyse tumor cells. These results suggest possibilities in the therapy of cystosarcoma phylloides involving vitamin C, certain hormones, and tumor-infiltrating lymphocytes.
 ...
PMID:Cultured breast cystosarcoma phylloides cells and applications to patient therapy. 196 88

A case-control study was undertaken in Athens to explore the role of passive smoking and diet in the causation of lung cancer, by histologic type, in non-smoking women. Among 160 women with lung cancer admitted to one of seven major hospitals in Greater Athens between 1987 and 1989, 154 were interviewed in person; of those interviewed, 91 were life-long non-smokers. Among 160 identified controls with fractures or other orthopedic conditions, 145 were interviewed in person; of those interviewed, 120 were life-long non-smokers. Marriage of a non-smoking woman to a smoker was associated with a relative risk for lung cancer of 2.1 (95% confidence interval [CI] 1.1-4.1); number of cigarettes smoked daily by the husband and years of exposure to husband's smoking were positively, but not significantly, related to lung cancer risk. There was no evidence of any association with exposure to smoking of other household members, and the association with exposure to passive smoking at work was small and not statistically significant. Dietary data collected through a semi-quantitative food-frequency questionnaire indicated that high consumption of fruits was inversely related to the risk of lung cancer (the relative risk between extreme quartiles was 0.27 (CI 0.10-0.74)). Neither vegetables nor any other food group had an additional protective effect; furthermore, the apparent protective effect of vegetables was not due to carotenoid vitamin A content and was only partly explained in terms of vitamin C. The associations of lung cancer risk with passive smoking and reduced fruit intake were independent and did not confound each other.(ABSTRACT TRUNCATED AT 250 WORDS)
Cancer Causes Control 1990 Jul
PMID:Passive smoking and diet in the etiology of lung cancer among non-smokers. 196 16

The purpose of this study was to determine the effect of the dietary antioxidant vitamin E on hepatocarcinogenesis by peroxisome proliferators which, it is hypothesized, induce tumors by increased production of hydrogen peroxide or other oxygen radicals. Rats were fed diets containing the peroxisome proliferator ciprofibrate and one of three concentrations (10, 50, or 500 ppm) of alpha-tocopheryl acetate for 6 months or 21 months. The incidence of hepatic tumors and the number and volume of gamma-glutamyl-transpeptidase-positive, ATPase-negative, glucose-6-phosphatase-negative, and glucose-6-phosphatase-positive foci were quantified. No tumors or altered hepatic foci were seen at 6 months, but at 21 months the incidence of hepatic tumors and the number and volume of altered hepatic foci were increased in rats fed higher levels of vitamin E. Indices of oxidative damage--concentrations of malonaldehyde, conjugated dienes, and lipid-soluble fluorescence products--were not affected or were lower in rats fed higher amounts of vitamin E; the enhancing effect of vitamin E on the development of altered hepatic foci and hepatic tumors, therefore, was not related to the induction of cellular oxidative damage. Hepatic peroxisomal fatty acid beta-oxidation and vitamin C concentrations were not affected by vitamin E, whereas the glutathione concentration was decreased in rats fed higher amounts of vitamin E. This study shows that increasing the vitamin E content of the diet enhances ciprofibrate-induced hepatocarcinogenesis, but the mechanism of this effect is unclear.
J Cancer Res Clin Oncol 1990
PMID:Effect of dietary vitamin E on the development of altered hepatic foci and hepatic tumors induced by the peroxisome proliferator ciprofibrate. 197 53

N-nitroso compounds (NOC) are strongly implicated in the causation of cancer of the stomach and it has been suggested that ascorbic acid might reduce the risk of gastric cancer by preventing their formation within gastric juice. However, until recently there have been no measurements of gastric juice ascorbic acid concentrations. We have measured both gastric juice ascorbic and total vitamin C (ascorbic acid and dehydroascorbic acid). Our findings suggest that ascorbic acid is secreted into the gastric lumen so that gastric juice concentrations are often greater than those in plasma. Gastric pathology affects this secretion, leading to values in gastric juice that are lower than plasma levels. Stimulation of gastric secretion does not raise vitamin C concentrations in individuals whose values are initially low. The role of ascorbic acid in preventing formation of NOC and protecting against gastric cancer is discussed in the light of these findings.
 ...
PMID:Gastric juice ascorbic acid: effects of disease and implications for gastric carcinogenesis. 198

Epidemiological studies have shown that diets rich in one or more antioxidant nutrients may reduce the risk of cancers of the lung, uterine cervix, mouth, and gastrointestinal tract. Study of premalignant lesions offers a comparatively expedient approach to identifying and evaluating the efficacy of the cancer chemopreventive components of foods. Some recent findings suggest roles for beta-carotene and/or vitamin C in reversing or reducing the risk of cervical dysplasia and oral leukoplakia. There are some indications that vitamin C and beta-carotene may reduce the risk of atrophic gastritis and gastric cancer. Additional epidemiological and molecular biology studies and clinical intervention trials using premalignant lesions as the marker of specific cancer risks should become an important component of future research in the area of cancer chemoprevention.
 ...
PMID:Premalignant lesions: role of antioxidant vitamins and beta-carotene in risk reduction and prevention of malignant transformation. 198 17

The carcinogenicity of long-term feeding of masheri extract to animals in a vitamin-A-sufficient (SLO+) and deficient (SLO-) state was studied in Sprague Dawley rats by feeding daily dose of 3 mg extract over a period of 21 months. The phase I activating enzymes, the glutathione (GSH)/glutathione S-transferase (GST) detoxification system, and the hepatic and circulating levels of vitamins A and C were also monitored at 12 and 21 months. It was observed that the phase I enzyme activities were significantly higher in SLO+ than in SLO- rats at both 12 months and 21 months. Moreover, the SLO- masheri-treated animals also showed a decreased in the GSH/GST detoxification system while the reverse was observed in SLO+ group. Masheri extract treatment significantly lowered the hepatic and circulating levels of vitamin A while a concurrent increase was observed in the vitamin C level. The extract was found to be tumorigenic in both the SLO+ and SLO- groups. Benign tumours were observed in the SLO+ group while a high incidence of malignant tumours of the lung were observed in the SLO- group upon treatment with masheri extract.
J Cancer Res Clin Oncol 1991
PMID:Carcinogenicity studies of masheri: pyrolysed tobacco product, in vitamin-A-deficient Sprague Dawley rats. 199 70

Sodium saccharin and sodium ascorbate are known to promote urinary bladder carcinogenesis in rats following initiation with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) or N-butyl-N-(4-hydroxybutyl) nitrosamine. Sodium salts of other organic acids have also been shown to be bladder tumor promoters. In addition, these substances increase urothelial proliferation in short term assays in rats when fed at high doses. When they have been tested, the acid forms of these salts are without either promoting or cell proliferative inducing activity. The following experiment was designed to compare the tumor promoting activity of various forms of saccharin and to evaluate the role in promotion of urinary sodium, calcium, and pH as well as other factors. Twenty groups of 40 male F344 rats, 5 weeks of age, were fed either FANFT or control diet during a 6-week initiation phase followed by feeding of a test compound for 72 weeks in the second phase. The chemicals were administered to the first 18 groups in Agway Prolab 3200 diet and the last 2 groups were fed NIH-07 diet. The treatments were as follows: (a) FANFT----5% sodium saccharin (NaS); (b) FANFT----3% NaS; (c) FANFT----5.2% calcium saccharin (CaS); (d) FANFT----3.12% CaS; (e) FANFT----4.21% acid saccharin (S); (f) FANFT----2.53% S; (g) FANFT----5% sodium ascorbate; (h) FANFT----4.44% ascorbic acid; (i) FANFT----5% NaS plus 1.15% CaCO3; (j) FANFT----5.2% CaS plus 1.34% NaCl; (k) FANFT----5% NaS plus 1.23% NH4Cl; (l) FANFT----1.15% CaCO3; (m) FANFT----1.34% NaCl; (n) FANFT----control; (o) control----5% NaS; (p) control----5.2% CaS; (q) control----4.21% S; (r) Control----control; (s) FANFT----5% NaS (NIH-07 diet); (t) FANFT----control (NIH-07 diet). NaS, CaS and S without prior FANFT administration were without tumorigenic activity. NaS was found to have tumor promoting activity, showing a positive response at the 5 and 3% dose levels, with significantly greater activity at the higher dose. CaS had slight tumor promoting activity but without a dose response, and S showed no tumor promoting activity. In addition, NaCl showed weak tumor promoting activity, but CaCO3 was without activity. NH4Cl completely inhibited the tumor promoting activity of NaS when concurrently administered with it. NaCl administered with CaS or CaCO3 administered with NaS showed activity similar to that of NaS. Sodium ascorbate was also shown to have tumor promoting activity, with slightly less activity than NaS. Ascorbic acid showed no tumor promoting activity.(ABSTRACT TRUNCATED AT 400 WORDS)
Cancer Res 1991 Apr 01
PMID:Comparative bladder tumor promoting activity of sodium saccharin, sodium ascorbate, related acids, and calcium salts in rats. 200 60

Data from 1,575 cases and 1,974 controls enrolled in 6 previously conducted case-control studies of diet and breast cancer have been analysed with respect to alcohol intake. There appears to be an absence of any association between consumption of up to 40 g of alcohol per day and risk of breast cancer, and a highly statistically significant and consistent elevated risk of breast cancer for drinkers of 40 g or more of alcohol per day, for whom the relative risk, as compared with that of non-drinkers, is 1.69 (95% confidence interval 1.19 to 2.40). This association is not due to confounding by a number of diet-related factors, including total calories, fat, fibre and vitamin C.
Int J Cancer 1991 Mar 12
PMID:The association between alcohol and breast cancer risk: evidence from the combined analysis of six dietary case-control studies. 200 52

A multicentric hospital-based case-control study was simultaneously performed in a high-risk and a low-risk area for stomach cancer in Germany, 143 patients with incident stomach cancer and 579 controls completing a retrospective interview about life style aspects. Periods of non-centralized water supply or well water as the only source compared to life-long central water supply, and preservation of meat by smoking it with spruce compared to no home smoking of meat, were significantly associated with an increased stomach cancer risk. use of a refrigerator at home for 30 and more years compared to 24 years or less showed an inverse relationship, whereas salt intake estimated by questionnaire showed no relationship to stomach cancer risk. Tobacco smoking was negatively associated with risk for current smokers of cigarettes compared to non-smokers but was presumably not causally related. After adjustment for other food constituents, only increased vitamin C consumption showed an inverse relation to risk. For food groups, increased consumption of fruit, citrus fruit, cheese and whole-meal bread were associated with decreased risk. A similar effect was also seen for increased consumption of raw vegetables. Total vegetable consumption was not particularly associated with risk. Increased consumption of processed meat and of beer showed a positive association with risk whereas increased wine and liquor consumption showed a significant negative association. The association of alcoholic beverages with stomach cancer risk may reflect a particular life style rather than being causally related to risk.
Int J Cancer 1991 Apr 01
PMID:Case-control study on stomach cancer in Germany. 201 Feb 28

The epidemiologic case-control study included 100 patients with histologically verified colorectal cancer. The groups of cancer patients and controls with non-tumor pathology treated at a therapeutic department of a city clinical hospital were identical with respect to age and sex. A questionnaire was used to study average intake of foods within 12 months prior to disease. Consumption of basic dietary ingredients was calculated. The logistic regression method was employed to assess the relative risk of colonic cancer development for four levels of consumption of each ingredient. The tendency of risk variation was evaluated. The increase in the risk of colonic cancer was accounted for by the high consumption of monounsaturated fatty acids (p = 0.023), starch (p = 0.05) and a rise in meat/vegetables (p less than 0.001), protein/cellulose (p less than 0.001) and fat/cellulose (p = 0.023) ratios. High intake of beta-carotene (p = 0.011), vitamin C (p = 0.003), calcium (p = 0.009) and dairy products (p = 0.003) and increased poly/mono-unsaturated fatty acid ratio (p = 0.014) were associated with low relative risk.
 ...
PMID:[The role of nutrition in the etiology of cancer of the large intestine]. 201 93


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>