Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

High fecal pH level has been suggested as a risk factor for colorectal cancer. We previously demonstrated that, although sodium sulfate did not affect the proliferation rate of colonic mucosa, as indicated by thymidine-labeling index, it did lower fecal pH in subjects at average risk for colon cancer. In the current study, we evaluated the effects of sodium sulfate on fecal pH and proliferation of colonic mucosa in subjects at high risk for colon cancer. Fifty-seven patients who had had colonic polyps removed were randomly assigned to two groups to receive either sodium sulfate (27 patients) or a placebo (25 patients) at a mean dose of 4 g/day for 14 days. Age, sex, height, and weight were comparable in both groups. Before intervention, levels of fecal pH were similar in the two groups, but after intervention, fecal pH was reduced only in the sodium sulfate group (mean decrease, 0.3 U; P less than .01). Thymidine-labeling index (number of labeled cells per number of cells counted) was similar in the two groups prior to intervention and did not change significantly after intervention (mean increase, 0.9%; P = .35). Regression analysis revealed no correlation between the change in labeling index and the change in fecal pH. We conclude that high fecal pH level is only indirectly associated with the development of colon cancer and, therefore, may be a secondary, rather than a primary, measure of cancer risk.
 ...
PMID:Effects of sodium sulfate on fecal pH and proliferation of colonic mucosa in patients at high risk for colon cancer. 234 29

The purpose of this work was to investigate whether sucrase-isomaltase from enterocyte-like differentiated human colon carcinoma cell lines carries blood group antigens of the ABH system. Six cultured lines of blood group A (HT-29, SW-480, Co-115) or O phenotype (Caco-2, HRT-18, HCT-8R) were studied. Only HT-29 cells grown in the absence of glucose (HT-29 Glc-) and Caco-2 cells express an enterocytic differentiation with the presence of sucrase-isomaltase on the apical surface of the cells. Binding of anti-A antibodies to HT-29 Glc- and of UEA-I to Caco-2 cells gave the same apical immunofluorescence pattern of staining as did anti-sucrase-isomaltase antibodies, whereas only a membrane binding was observed in nondifferentiated cells. Sucrase-isomaltase immunoisolated from HT-29 Glc- and Caco-2 cells reacted with anti-A antibodies and Ulex europaeus agglutinin-I (UEA-I), respectively, at sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot. Immunoprecipitation of solubilized brush border-enriched fractions from the same cells with UEA-I or anti-A antibodies resulted in an inhibition of sucrase activity which reached congruent to 80% for Caco-2 cells with UEA-I and approximately equal to 50% for HT-29 cells with anti-A antibodies. Similar results were obtained in the corresponding tumors in nude mice: anti-A antibodies in HT-29 and UEA-I in Caco-2 tumors bound to the same apical structures as did anti-sucrase-isomaltase antibodies; sucrase-isomaltase immunoisolated from the tumors bound anti-A antibodies (HT-29) or UEA-I (Caco-2). These results support the hypothesis that sucrase-isomaltase from enterocyte-like differentiated human colon cancer cells carries blood group antigens of the ABH system. These findings suggest that colon cancers which have been shown to display an apical pattern of expression of ABH antigens should be screened for their possible enterocytic differentiation.
 ...
PMID:A and H blood group antigens as markers of sucrase-isomaltase from the enterocyte-like differentiated human colon carcinoma cell lines HT-29 and Caco-2. 243 17

CA-549 is a circulating breast cancer-associated antigen that reacts with monoclonal antibody BC4E 549. Biochemical characterization of CA-549 revealed that it is an acidic (isoelectric point 5.2) glycoprotein that exhibits two bands by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions of apparent molecular weights of 400,000 and 512,000. Immunohistochemical staining of unfixed frozen tissue sections of human breast tumors and a variety of benign tissues with BC4E 549 revealed no preferential staining of tumor over benign breast tissue and cross-reactivity with a wide range of other benign tissues including kidney, liver, lung, colon, pancreas, ovary, and spleen. Serum levels of CA-549 were initially tested by an enzyme-linked immunosorbent assay inhibition using BC4E 549. This assay showed that CA-549 concentrations were elevated in 19 of 27 sera from patients with advanced breast cancer compared to 0 of 22 and 0 of 129 sera from benign breast disease patients and healthy females, respectively. These preliminary data suggested that CA-549 was a useful breast tumor marker; thus BC4E 549 was adapted to a sandwich immunoradiometric assay format suitable for routine use in the clinical laboratory and its performance was evaluated on a panel of 668 serum samples. The test detected significant concentrations of CA-549 in the sera of 40 of 80 patients with advanced breast cancer, 1 of 30 with early breast cancer, 4 of 19 with advanced lung cancer, 2 of 40 with advanced colon cancer, and 5 of 29 with advanced prostate cancer. The test showed a high degree of specificity, producing false-positives in only 3 of 79 benign breast patients, 2 of 25 benign liver patients, 2 of 70 benign colon patients, 2 of 19 benign lung patients, 0 of 20 benign prostate patients, and 3 of 257 healthy individuals. These data represent an overall 50% sensitivity and 98% specificity as a test for advanced breast cancer. These data indicate that this immunoradiometric assay is a useful test for the detection of circulating CA-549 in advanced breast cancer patients and suggest that it may prove useful as a monitor in the management of that disease.
 ...
PMID:Serum levels and biochemical characteristics of cancer-associated antigen CA-549, a circulating breast cancer marker. 244 35

Sulfur dioxide absorbs ultraviolet light in the region of the spectrum which is most active in forming vitamin D on the skin. Sulfate particles reflect light at this wavelength. High concentrations of these pollutants (acid haze) may lead to vitamin D deficiencies in exposed populations. Epidemiologic and laboratory evidence suggests that vitamin D plays a role in reducing risk of colon and breast cancer. We examined the association between sulfur dioxide and ultraviolet-light-blocking aerosols in 20 Canadian cities, and age-adjusted breast and colon cancer mortality rates in the census divisions encompassing these cities. Statistically significant positive associations were found between these two measures of air pollution and age-adjusted mortality rates for colon cancer in women (multiple r = +.74, p = 0.003), and men (multiple r = +.61, p = 0.03), and breast cancer in women (multiple r = +.69, p = 0.007). Mortality rates for all other reported cancer sites were also examined, and no statistically significant positive associations were found consistently in both sexes. The ecological nature of this study is emphasized, and the possibility that an indirect association could explain these findings is discussed.
 ...
PMID:Acid haze air pollution and breast and colon cancer mortality in 20 Canadian cities. 272 May 47

Colon cancer cells in culture synthesize and secrete mucin glycoproteins, which carry a number of cancer-associated antigens. However, the structures and mechanisms of biosynthetic processing are not well understood. Mucins synthesized and secreted by LS174T human colon cancer cells were compared to those in LS174T xenografts in athymic mice. Mucins radiolabeled with glucosamine or sulfate were purified by gel filtration and cesium chloride density gradient centrifugation. The mucins were of high molecular weight and were resistant to chondroitinase ABC, hyaluronidase and HNO2 treatment. They were, however, susceptible to pronase digestion and mild alkaline treatment. Using radiochemical precursors, the cellular mucin was shown to contain fucose, galactose, N-acetylgalactosamine, N-acetylglucosamine, N-acetylneuraminic acid, and sulfate. Oligosaccharides released by beta-elimination had N-acetylgalactosaminitol as the reduced amino sugar and also unreduced galactosamine, indicating that there is N-acetyl-galactosamine O-glycosidically attached to protein core and also peripheral N-acetyl-galactosamine not directly linked to protein. DEAE-cellulose chromatography of mucins showed two major peaks with both intracellular and secreted mucins, but xenograft mucins also had more acidic components. Sulfate-labeled mucins were shifted to less acidic peaks by neuraminidase digestion, which indicates that the same mucin molecules are both sialylated and sulfated. We conclude that the intracellular mucins of cultured colon cancer cells, those secreted into the medium, and those in nude mouse xenografts are chemically similar, but differ in sialic acid and sulfate content. This experimental model system, LS174T cells maintained in culture and as nude mouse xenografts, may be useful for further biosynthetic and structural studies of colon cancer mucin.
 ...
PMID:Comparison of metabolically labeled mucins of LS174T human colon cancer cells in tissue culture and xenograft. 273 49

An inhibitor of soft agar colony formation by a human breast carcinoma-derived cell line was found to be present in latent form in the majority of cytology-positive human malignant effusions. Prior to dialysis, addition of human malignant effusions resulted in less than 10% alteration in efficiency of colony formation by the BT-20 human breast carcinoma cell line (mean efficiency 1 colony/4.3 cells plated at 14 days; mean colony diameter greater than 0.8 mm). After dialysis (membrane cutoff of 3500 molecular weight), 58 of 70 malignant effusions from patients with a variety of epithelial cell carcinomas resulted in 71% mean inhibition of colony formation (range 19.1-98% inhibition). Similar inhibition of anchorage-independent growth was observed for a human colon cancer-derived cell line (HCT-15) but not for polyoma and murine sarcoma virus-transformed rodent fibroblast lines. The malignant effusion-related transformed cell growth-inhibiting factor (TGIF) was sensitive to heat, sulfhydryl reduction, and protease treatment. TGIF-containing effusion resulted in parallel inhibition of thymidine incorporation in sensitive cell types in vitro. TGIF was precipitable in 28-34% ammonium sulfate with reconstitution of activity after resolubilization. TGIF was partially purified by chromatography on Biogel A-0.5 and Biogel P-100 which yielded two peaks of inhibitory activity. The predominant species had an approximate molecular weight of 110,000 and could be recovered as a single species from DEAE-cellulose at relatively high salt concentrations (0.4 M NaCl). A smaller amount of inhibitory activity was recovered from Biogel P-100 or Biogel P-60 with an apparent molecular weight of 55,000. The higher molecular-weight TGIF which appears to be a dimer of the Mr 55,000 protein is distinguishable from previously described growth-promoting and -inhibiting factors.
 ...
PMID:Latent transformed growth-inhibiting factor in human malignant effusions. 325 64

The human colon cancer cell line Caco-2 cultured in vitro displayed morphological differentiation which was shown to be a growth-related event. We have investigated this phenomenon further in relation to the cell surface glycosaminoglycans produced by growing (5-day, i.e., prior to differentiation) and confluent (9-day, i.e., after morphological and functional differentiation) cultures. Neosynthesized [35S]glycosaminoglycans were purified on DEAE-cellulose; at confluency, they were bound more strongly to the column than the corresponding fractions from the growing cells. Analysis of Kav values of heparan sulfate and chondroitin sulfates from growing and confluent cells indicated an increase in chain length of both glycosaminoglycans in morphologically differentiated cells. Heparan sulfate was the main 35S-labeled glycosaminoglycan of the cell surface of both 5-day and 9-day cultures. Paper chromatography of the unsaturated disaccharides obtained by chondroitinase digestion showed that chondroitin sulfate chains were primarily 6-sulfated in the 2 studied extracts. Heparan sulfate chains were isolated as chondroitinase-resistant material and treated with nitrous acid. Analysis of N- and O-sulfate group-related radioactivity showed an increase in the amount of 35S-label in the form of N-sulfate groups and an increase in the O-35S-sulfation pattern in heparan sulfate from morphologically differentiated cells. Thus, the structural features of both chondroitin sulfates and heparan sulfate were significantly different when the growing cells became morphologically differentiated.
 ...
PMID:Biosynthesis of glycosaminoglycans in the human colonic tumor cell line Caco-2: structural changes occurring with the morphological differentiation of the cells. 340 19

Two Crohn's disease tissue-specific proteins are identified and purified several thousand-fold from crude tissue extracts by different chromatographic procedures. The two proteins migrate in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as 200-210-kilodalton and 150-160-kilodalton species. They are glycoproteins, as evidenced by their binding to concanavalin A-Sepharose 4B and positive staining with Schiff's reagent. Specific immunoreactivity of the two glycoproteins against Crohn's disease sera was demonstrated by immunotransblot analysis. All but one of the operative specimens of colon or small intestine (or both) from 13 patients with Crohn's disease contained either or both of the proteins; they were not detected in specimens of colon from 5 patients with ulcerative colitis, 1 patient with diverticulitis, 1 patient with ischemic colitis, from the normal bowel segments resected from 3 patients with colon cancer, and from two normal ileal tissue specimens. The two glycoproteins did not react with antihuman IgG, IgM, and IgA, suggesting that they are not immunoglobulins. The purified glycoproteins may provide important leads toward the understanding of the pathogenesis of Crohn's disease.
 ...
PMID:Isolation and characterization of Crohn's disease tissue-specific glycoproteins. 352 40

Sulfated macromolecules synthesized in tumor and mucosa tissues derived from colorectal cancer patients were labeled with [35S]sulfate and separated into two fractions on DEAE-Sephacel: the slightly acidic peak (peak I) was eluted with 0.2 M NaCl and the highly acidic peak (peak II) was eluted with 0.5 M NaCl. A total of 40 specimens, which included primary colon cancer, liver metastases, and normal mucosa obtained at surgery (16 patients), were examined regarding the amount of peak I and peak II. The amount of peak I significantly decreased in the order of normal mucosa greater than primary tumors greater than metastases, while the amount of peak II did not significantly change among the tissues. Peak I was mostly resistant to chondroitinase ABC and nitrous acid treatment under acidic conditions, whereas combined chondroitinase-sensitive materials and nitrous acid-sensitive materials were greater than 80% of the radioactivity in peak II. The major radioactive component of peak I migrated at a position corresponding to Mr greater than 300,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and became Mr less than 40,000 after alkaline borohydride treatment. The major component of peak I was likely to be a sulfated glycoprotein containing sulfate groups on alkaline labile carbohydrate chains. Peak II consisted of a mixture of heparan sulfate proteoglycans and chondroitin sulfate proteoglycans. Differential incorporation of [35S]sulfate into peak I among normal mucosa, primary colon carcinoma, and colon carcinoma metastasis was observed. Therefore, decreased peak I production may be a biochemical change associated with colorectal cancer progression and metastasis.
 ...
PMID:Differential production of high molecular weight sulfated glycoproteins in normal colonic mucosa, primary colon carcinoma, and metastases. 356

The LAI reactivity of a colon organ specific neoantigen (OSN) was recovered from the urine of advanced colon cancer patients. In this study three physico-chemical steps were employed; precipitation by 80% ammonium sulfate, ion exchange, and molecular sieve chromatography. Each isolate was tested for activity and specificity by the direct tube leukocyte adherence inhibition (LAI) assay employing leukocytes from colon and breast cancer patients. The OSN enriched isolate was then used to generate monoclonal antibodies (Mab). Hybridomas were screened by ELISA. One hybridoma designated Bac 18.1 reacted preferentially with colon OSN and not with the urine from normals or patients with breast cancer. Affinity purification of colon OSN was achieved and it was shown to consist of a single band in SDS-PAGE with an apparent molecular weight of 30,000. The eluted polypeptide was specifically reactive in ELISA as well as in the LAI assay.
 ...
PMID:The isolation of colon cancer organ specific neoantigen by the use of the leukocyte adherence inhibition assay and monoclonal antibodies. 375 60


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