Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009402 (colorectal cancer)
 53,228 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This article is an attempt to study the metabolic functions of vitamin C and E together. Such a study must necessarily be imcomplete owing to the extreme richness of the literature. The increasing importance of the work on free radical reactions, their toxicity and carcinogenic action, and also their relation to the metabolism of metals, particularly iron, copper, selenium, and zinc, shows a number of metabolic pathways with which both vitamins interact. It is hoped that this article will indicate future research possibilities.
CRC Crit Rev Food Sci Nutr 1979
PMID:The antioxidant vitamins. 37 49

In patients with primary biliary cirrhosis and Wilson's disease liver copper concentrations become elevated during the evolution of the disorder. The accumulated copper is thought to be detoxified by metallothionein, a protein which binds copper and zinc. In liver metastasis of colorectal cancer, copper and zinc concentrations are usually decreased compared to normal liver tissue, but little is known about the concomitant metallothionein levels. In the present study metallothionein concentrations were determined in archival liver samples from patients with primary biliary cirrhosis and Wilson's disease, and in both normal and malignancy-containing liver samples from patients with metastasis from a colorectal adenocarcinoma. Twenty-seven control liver samples contained 3.98 +/- 1.55 mg metallothionein/g protein. From the 21 liver samples of patients with primary biliary cirrhosis, which had a mean metallothionein concentration of 6.06 +/- 5.03 mg/g protein, 6 were above the highest control level. Liver metallothionein concentrations for the 8 patients with Wilson's disease were significantly elevated (10.98 +/- 6.93 mg/g protein, p < 0.005 vs. controls and p < 0.05 vs. primary biliary cirrhosis). In the 11 liver metastases from colorectal adenocarcinomas metallothionein concentrations (1.17 +/- 0.90 mg/g protein) were significantly (p < 0.005) lower than surrounding normal liver tissue (4.25 +/- 1.75 mg/g protein). We conclude that in primary biliary cirrhosis and Wilson's disease increased liver metallothionein concentrations may detoxify the accumulated copper. Furthermore, liver metastasis of colorectal cancer contains less metallothionein than the surrounding normal liver tissue.
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PMID:Metallothionein concentration in the liver of patients with Wilson's disease, primary biliary cirrhosis, and liver metastasis of colorectal cancer. 148 12

Oxygen derived radicals contribute to tissue injury in inflammatory bowel disease. We measured the content of superoxide dismutase and metallothionein (two endogenous copper and zinc containing proteins involved in radical scavenging) in intestinal resection specimens from 29 patients with Crohn's disease and 12 patients with ulcerative colitis and compared the concentrations with those obtained in the normal mucosa of a control group of 18 patients with colorectal cancer. The superoxide dismutase content was similar in control mucosa and non-inflamed mucosa from patients with inflammatory bowel disease (mean (SEM) 2.13 (0.10) and 2.24 (0.10) mg/g protein, respectively) but was decreased in inflamed mucosa (1.87 (0.08) mg/g protein, p less than 0.005 v non-inflamed mucosa). The metallothionein content was decreased in non-inflamed inflammatory bowel disease mucosa compared with control mucosa (0.23 (0.03) and 0.36 (0.04) mg/g protein, respectively, p less than 0.02) and a further decrease was found in inflamed mucosa (0.17 (0.02) mg/g protein, p less than 0.001 v control mucosa). No differences were found between Crohn's disease and ulcerative colitis and no significant effect of medication or tissue localisation was noted. These findings might indicate a decreased endogenous intestinal protection against oxygen derived radicals in inflammatory bowel disease which could contribute to the pathogenesis of the disease.
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PMID:Decrease in two intestinal copper/zinc containing proteins with antioxidant function in inflammatory bowel disease. 195 69

Carcinogenic metal levels in serum and tissue samples were measured in patients with bronchopulmonary or colorectal cancer. The cadmium and nickel tissue levels in the patients with lung cancer were significantly higher than in the controls. A statistical correlation was found between chromium and cadmium, as well as between cadmium and nickel in patients with colorectal cancer. In addition, prior to the operation, the tumor markers alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen (Ca 19-9), polypeptide histidio antigen (TPA) and ferritin were analyzed. Their average concentrations were correlated with the existing concentrations of the metals. This was done for both types of cancer. Tumor marker detection showed an increase of CEA and TPA in patients with colorectal cancer. A statistical correlation was observed between AFP and zinc tumor tissue.
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PMID:Comparative analysis of certain metals and tumor markers in bronchopulmonary cancer and colorectal cancers. Metals and tumor markers in the neoplastic process. 210

One hundred ninety-two patients with previously untreated metastatic cancer (102 non-small-cell lung cancer [NSCLC]; 90 colorectal cancer) were randomized to receive either ad lib nutritional intake (control group) or specific nutritional intervention during a 12-week study period when chemotherapy was administered. Those patients randomized to nutritional interventions were counselled to take oral nutrients with caloric intake equal to 1.7 to 1.95 times their basal energy expenditure, depending on their pretreatment nutritional status ("standard" group). An augmented group was counselled to have a caloric intake equivalent to that of the standard group but with 25% of calories provided as protein and additional supplements of zinc and magnesium. Counselling increased caloric intake in both tumor types but reduced weight loss in the short term only for lung cancer patients. Ninety-three NSCLC patients were evaluable for tumor response to vindesine and cisplatin. Overall, only 20.4% of the patients responded, and there were no significant differences in response rates, median time to progression, or overall duration of survival between the nutrition intervention groups and the control group. The tumor response rate to time-sequenced 5-fluorouracil (5-FU) and methotrexate in the 81 evaluable patients with colorectal cancer was only 14.8%, and no significant differences in tumor response rates were noted between the three groups. Furthermore, the median time to progression and overall duration of survival were not different for the control, standard, and augmented groups. Nutritional interventions using dietary counselling had no impact on the percent of planned chemotherapy dose administered, the degree of toxicity experienced by patients, or the frequency of treatment delays. A multivariate prognostic factor analysis demonstrated that for lung cancer, the percent of weight loss, serum albumin concentration, and presence of liver metastases were significant (P less than .05) and independent prognostic variables for survival duration. For colorectal cancer, serum albumin, alkaline phosphatase, lactic dehydrogenase (LDH) levels, and percent targeted caloric intake (TCI) were significant independent predictors of survival duration.
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PMID:A randomized study of oral nutritional support versus ad lib nutritional intake during chemotherapy for advanced colorectal and non-small-cell lung cancer. 302 67

Variations in dietary exposure to several minerals may alter the risk of acquiring colorectal cancer. These minerals include selenium, zinc, calcium, sodium, potassium, iron and fluoride. The mechanism by which each of these minerals alters cancer risk is not established. However, as both the epidemiologic and experimental evidence for major calorie sources, fat and protein, being the primary determinants of colorectal cancer risk is weakening, micronutrients may prove to be the primary determinants of risk in human colorectal cancer.
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PMID:Dietary minerals and colon carcinogenesis (review). 329 40

The current status of superoxide dismutase (SOD) is that it is an enzyme with diverse ramifications. This review attempts an understanding of SOD as a structural, functional, and biological entity. Accordingly, the review is in three parts. The first part discusses SOD in terms of protein structure, proceeding from primary to secondary and three-dimensional structure for the three forms of SOD: copper/zinc SOD, manganese SOD, and iron SOD. This is the order of structural knowledge of the enzyme. Iron SOD is an enzyme of prokaryotes and some higher plants. Manganese SOD is an enzyme of prokaryotes and eukaryotes. Copper/zinc SOD is an enzyme of eukaryotes and certain prokaryotes. The evolutionary relationships of the three forms of SOD, the status of the copper/zinc SOD gene in prokaryotes, and the cloning and sequencing of SOD genes are discussed. The second part of the review deals with the catalytic mechanism of SOD in the three forms of the enzyme. Structural and mechanistic conclusions from various spectroscopic studies are critically considered. A detailed picture is given of the active site of copper/zinc SOD. The third part is a review of SOD in the general context of oxygen toxicity. After consideration of the question of superoxide toxicity and superoxide pathology, several areas in which SOD has been investigated or used as a tool in a biochemical, pharmacological, or clinical context are discussed, including population genetics; trisomy 21; development and senescence; the nutritional copper, zinc, and manganese status; hemolysis and anemia; oxygen toxicity in the lung and nervous system; inflammation, autoimmune disease and chromosome breakage, ischemia and degenerative changes; radiation damage; and malignancy. A comprehensive picture is given of measurements of SOD activity in disease states, and the question of superoxide-related disease is considered at several points.
CRC Crit Rev Biochem 1987
PMID:Aspects of the structure, function, and applications of superoxide dismutase. 331 61

An hypothesis is presented to explain the changing pattern of colorectal cancer seen within the United States and other western countries in the last 30 years, the simultaneous increase of right-sided colonic cancer and disappearance of rectal cancer. Review of experimental and epidemiologic data suggests that this change may be due to a new systemic deficiency of the trace element, selenium. This deficiency has arisen not just from decreased consumption of selenium in the last 30 years, but also from increased consumption of zinc and fluoride, which may antagonize the effect of selenium.
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PMID:Is the changing pattern of colorectal cancer caused by selenium deficiency? 674 17

Although several studies have described an increase in urinary zinc output in cancer patients, little attention has been paid to the excretion of copper. In this study, we investigated urinary excretion of zinc and copper, and serum levels of alpha-1 acid glycoprotein, an acute phase protein, in 22 patients with colorectal cancer. Urinary excretion of copper and zinc were significantly increased compared to the reference group (77 +/- 72 vs. 32 +/- 14 mumol/mol creatinine, P < 0.05, and 1.50 +/- 0.62 vs. 0.70 +/- 0.41, P < 0.002, respectively). In addition, a negative correlation was observed between urinary copper and serum alpha-1 acid glycoprotein (rs = -0.5256, P < 0.02). In conclusion, urinary excretion of copper, as well as that of zinc, appears to be elevated in colorectal cancer. The finding of a negative correlation between urinary copper and alpha-1 acid glycoprotein supports the postulated role of the latter in regulating renal glomerular permselectivity.
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PMID:Increased urinary zinc and copper excretion in colorectal cancer. 759 14

The zinc-insulin hexamer, the storage form of insulin in the pancreas, is an allosteric protein capable of undergoing transitions between three distinct conformational states, designated T6, T3R3, and R6, on the basis of their ligand binding properties, allosteric behavior, and pseudo point symmetries [Kaarsholm, N. C., Ko, H.-C., & Dunn, M. F. (1989) Biochemistry 28, 4427-4435]. The transition from the T-state to the R-state involves a coil-to-helix transition in residues 1-8 of the B-chain wherein the ring of PheB1 is displaced by approximately 30 A. This motion also is accompanied by small changes in the positions of A-chain residues and other B-chain residues. In this paper, one- and two-dimensional (COSY and NOESY) 1H NMR are used to characterize the ligand-induced T to R transitions of wild-type and EB13Q mutant human zinc-insulin hexamers and to make sequence-specific assignments of all resonances in the aromatic region of the R6 complex with resorcinol. The changes in the 1H NMR spectrum (at 500 and 600 MHz) that occur during the T to R transition provide specific signatures of the conformation change. Analysis of the dependence of these spectral changes for the phenol-induced transition as a function of the concentration of phenol establish (1) that the interconversion of T6 and R6 occurs via a third species assigned as T3R3 and (2) that the system shows both negative and positive cooperative allosteric behavior. One- and two-dimensional COSY and NOESY studies show that, in the absence of phenolic compounds, anions act as heterotropic effectors that shift the distribution of hexamer conformations in favor of the R-state with the order of effectiveness, SCN- > N3- >> I- >> Cl-. Analysis of one- and two-dimensional spectra indicate that with wild-type insulin, SCN- and N3- give T3R3 species, whereas the EB13Q mutant gives an R6 species. An allosteric model for the insulin T to R transition based on the structural asymmetry model [Seydoux, F., Malhotra, O. P., & Bernhard, S. A. (1974) CRC Crit. Rev. Biochem. 2, 227-257] is proposed that explains the negative and positive allosteric properties of the system, including the role of T3R3 and the action of homotropic and heterotropic effectors.
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PMID:Structural asymmetry and half-site reactivity in the T to R allosteric transition of the insulin hexamer. 794 11


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