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

A method is described for the analysis of fecal neutral steriods with a dual-column gas-liquid chromatography (GLC) system. After saponification of the fecal slurry, the neutral steroids were extracted with hexane. The GLC separation of the compounds and quantitation were achieved by simultaneous injection of the derivatized and derivatized aliquots of the extract onto dual colmuns under identical conditions. The neutral steroids of interest were than identified by matching the retention times with those of known standards, and identification was confirmed by use of an interfaced GLC high-resolution mass spectrometry system. The detection limit was 0.003 mg of steroid/g of fecal slurry. The pricision of the method is illustrated by a relative standard diviation of 2-10% and a recovery of neutral steroids from 73-96%. The method was applied to the determination of fecal neutral steroids in a "High protein diet in colon cancer study". A considerably larger level of coprostanone than of coprostanol was observed. Data on neutral steroids in fecal samples from subjects on different diets are the subject of a separate publication.
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PMID:Gas-liquid chromatography of fecal neutral steriods. 32 2

Fecal mutagenic activity and dietary pattern of rural and urban Finnish population groups with distinct risk for the development of colon cancer were studied in a low-risk population in rural Kuopio and an intermediate-risk population in urban Helsinki. The average daily intake of protein and fat was the same in the two groups but the frequency of consumption of whole-grain cereals and whole-grain bread, as well as the amount of fiber from the bread were higher in Kuopio as compared to Helsinki. Fecal samples collected for 2 days were incubated under anaerobic conditions at 37 degrees C for 96 h, extracted with hexane: peroxide-free diethyl ether, partially purified on a silica Sep-Pak cartridge, and assayed for mutagenic activity using the Salmonella typhimurium/mammalian microsome system. The fecal mutagenic activity was observed with the tester strains TA98 and TA100 with and without microsomal activation in both the population groups. The percentage of samples showing fecal mutagenic ratio greater than 3 with TA98 and TA100 with microsomal activation, was higher in volunteers from Helsinki than in Kuopio.
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PMID:Metabolic epidemiology of colon cancer: fecal mutagens in healthy subjects from rural Kuopio and urban Helsinki, Finland. 299

Because of potential significance of fecal mutagens (presumptive carcinogens) in the pathogenesis of colon cancer, feces from 99 healthy subjects from the New York metropolitan area were studied. The diet histories indicate that all participants were consuming a mixed-western diet which is high in total fat and low in fiber. Fecal samples that were incubated under anaerobic conditions at 37 degrees C for 96 h or frozen without incubation, were extracted with hexane: peroxide-free diethyl ether (1:1), partially purified on a silica Sep-pak cartridge and assayed for mutagenicity using the Salmonella typhimurium/mammalian microsome system. Aliquots of fecal samples incubated anaerobically showed a higher frequency of mutagenic activity (per cent samples showing activity) in strains TA98 and TA100 with and without microsomal (S9) activation. In addition, the mutagens requiring S9 activation, were more frequently inactivated when the fecal samples were frozen immediately after defecation and transported to the laboratory. Compared with hexane: ether, extraction of fecal samples with acetone increased the mutagenic activity mostly with TA98 with S9 activation. The HPLC fractionation of hexane: ether extract with methanol: water gradient using reverse phase C-18 column and UV detector at 254 nm indicated that the mutagenic activity (TA98 with S9 activation) is concentrated in several peaks. This is the first demonstration of HPLC profile of fecal samples that are active in TA98 with S9 activation. HPLC profile of fecal extracts and mutagenic activity of these extracts in strains TA98 and TA100 suggest the presence of several types of mutagens in the feces of healthy subjects consuming a high-fat, low-fiber mixed-western diet.
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PMID:Fecal mutagens from subjects consuming a mixed-western diet. 631 89

Inducible cyclooxygenase (COX-2) has been implicated in the processes of inflammation and carcinogenesis. Thus, the potential COX-2 inhibitors have been considered as anti-inflammatory or cancer chemopreventive agents. In this study, the methanolic extract of the cortex of Eugenia caryophyllata Thunberg (Myrtaceae) was found to potently inhibit the prostaglandin E(2) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW264.7 cells (98.3% inhibition at the test concentration of 10 microg/ml). Further, hexane-soluble layer was the most active partition compared to ethyl acetate, n-butanol, and water-soluble parts. By bioassay-guided fractionation of hexane-soluble partition, eugenol was isolated and exhibited a significant inhibition of PGE(2) production (IC(50) = 0.37 microM). In addition, eugenol suppressed the cyclooxygenase-2 (COX-2) gene expression in LPS-stimulated mouse macrophage cells. On the line of COX-2 playing an important role in colon carcinogenesis further study was designed to investigate the effect of eugenol on the growth and COX-2 expression in HT-29 human colon cancer cells. Eugenol inhibited the proliferation of HT-29 cells and the mRNA expression of COX-2, but not COX-1. This result suggests that eugenol might be a plausible lead candidate for further developing the COX-2 inhibitor as an anti-inflammatory or cancer chemopreventive agent.
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PMID:Eugenol suppresses cyclooxygenase-2 expression in lipopolysaccharide-stimulated mouse macrophage RAW264.7 cells. 1275 41

A hexane extract of the plant product Chios mastic gum (He-CMG) is demonstrated to kill human colon cancer cells in vitro via the process of anoikis. Specifically, the sequence of events includes He-CMG-induced GI-arrest of the cells, detachment of the cells from the substrate and subsequent apoptosis. Anoikis is dependent on the concentration and duration of treatment with He-CMG. Presence of the pan-caspase inhibitor, Z-VAD-fmk, did not prevent cell detachment, but it did prevent apoptosis of the detached cells indicating that the process of cell detachment, but not apoptosis, is independent of caspase activation. He-CMG-induced apoptosis is associated with activation of the initiator caspases-8, and -9 and the effector caspase-3. Caspases are activated in cells at a relatively long time after detachment, and caspase-3 activation may require caspase-8 or caspase-9 activation, as determined by using HCT116 isogenic clones impaired in apoptosis mechanisms that involve these two caspases. Finally, electron microscopy observations indicated a time-dependent appearance of morphological features both typical and non-typical of apoptosis in cells treated with He-CMG for various periods of time. Taken together, the results demonstrated that He-CMG induces apoptosis in HCT116 cells and, therefore, further in vivo and in vitro studies of the anticancer activities of this plant product are warranted.
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PMID:Induction of apoptosis in human colon cancer HCT116 cells treated with an extract of the plant product, Chios mastic gum. 1579 60

Hexane extract from the bark of Amphipterygium adstringens, as well as its principal constituents, masticadienonic acid and 3alpha-hydroxymasticadienolic acid, inhibited the growth of five human cancer cell lines. Derivatives of, namely 24,25 S-dihydromasticadienonic acid and masticadienolic acid, were also evaluated. The results showed that both and had greater activity than on colon cancer cell lines. The effects of on the production of nitric oxide (NO) from both resting and lipopolysaccharide-activated macrophages were determined. It was found that and caused an increase in NO release from resting macrophages; in lipopolysaccharide-activated macrophages, only and caused an increase in NO production.
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PMID:Cytotoxic activity and effect on nitric oxide production of tirucallane-type triterpenes. 1610 29

The wild sarsaparilla (Aralia nudicaulis) plant is richly distributed in North America, mainly in Canada. In the present study, 24 extracts were obtained from the rhizome, stem, leaf and fruit of wild sarsaparilla. In the presence of RH (hexane fraction from the rhizome), the survival rate of WiDr (human colon cancer cell) was 3.5 +/- 2.7% (IC50 = 30.1 +/- 3.5 microg/ml) and that of Molt (human leukemia cell) was 2.4 +/- 2.8% (IC50 = 7.0 +/- 0.6 microg/ml). The survival rate of HELA (human cervix cancer cell) was only 1.8 +/- 0.9% in the presence of FH (hexane fraction from the fruit of wild sarsaparilla) (IC50 = 33.3 +/- 2.7 microg/ml). The cytotoxicities of RH and FH against normal human umbilical vein endothelial cells were significantly lower than against the tested human cancer cells. RH appeared to be the best extract against WiDr and Molt, whereas FH was the most effective against HELA. Because of the rich natural supply, simple extraction procedure and high yield, RH and FH of wild sarsaparilla have the potential to be developed into selective anticancer nutraceutical and/or pharmaceutical products with few side-effects and low cost.
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PMID:Anticancer effect of extracts from a North American medicinal plant--wild sarsaparilla. 1682 59

In the present investigation, the cytotoxic, hydroxyl radical scavenging and topoisomerase inhibition activities of Tabernaemontana divaricata (Apocynaceae) were evaluated. The extracts from leaves of the plant were prepared with different solvents viz. chloroform, methanol, ethyl acetate and hexane. In, in vitro cytotoxicity assay, with cell lines viz HCT-15 (Colon), HT-29 (Colon), 502713 (Colon), MCF-7 (Breast), PC- 3 (Prostrate), it was observed that the ethyl acetate extract was effective against only one colon cell line (502713) at the lowest dose i.e. 10 micro g/ml, whereas the chloroform extract was effective against all the three colon cancer cell lines, at 30 microg/ ml. In order to evaluate the mechanism of cytotoxicity of these extracts, they were assessed for their ability to scavenge hydroxyl radicals in plasmid nicking assay with pBR322. It was observed that all the extracts effectively inhibited the unwinding of supercoiled DNA except hexane extract, which showed the least effect. Since the expression of topo enzymes is linked with cell proliferation so the extracts were also checked for topo I and topo II inhibitory activities. It was noticed that ethyl acetate extract selectively showed inhibition of topo II in topoisomerase II relaxation assay.
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PMID:Studies on cytotoxic, hydroxyl radical scavenging and topoisomerase inhibitory activities of extracts of Tabernaemontana divaricata (L.) R.Br. ex Roem. and Schult. 1857 13

Doxorubicin (DOX) is an anthracycline antibiotic, and has been recognized as one of the most effective anti-neoplastic agents in cancer chemotherapy. However, its usefulness is limited by its profound cardiotoxicity. Licorice is one of the most frequently prescribed agents in traditional herbal medicine, and is also employed as a natural sweetening additive. In traditional Chinese medicine, licorice root is added to a variety of herbal preparations to detoxify the effects of the other herbs in the preparation. In the present study, we explored the possibility that Glycyrrhiza uralensis licorice may alleviate DOX-induced cardiotoxicity. The hexane/ethanol extract of Glycyrrhiza uralensis (HEGU), which lacks glycyrrhizin, was prepared because glycyrrhizin intake has previously been reported to induce hypertension. In an effort to determine whether HEGU ameliorates DOX-induced cytotoxicity in H9c2 rat cardiac myoblasts, the cells were pretreated with 0-15 mg/L HEGU, then treated with doxorubicin. The pretreatment of cells with HEGU resulted in a significant mitigation of DOX-induced reductions in cell numbers (34 +/- 7%) and increases in apoptosis (53 +/- 1%). The Western blot analysis of cell lysates showed that HEGU suppressed DOX-induced increases in the levels of p53, phospho-p53 (Ser 15), and Bax. In addition, HEGU induced an increase in the levels of Bcl-xL, regardless of DOX-treatment. HEGU inhibited the DOX-induced cleavage of caspases 9, 3, and 7, as well as DOX-induced poly(ADP-ribose) polymerase cleavage. Furthermore, HEGU caused reductions in the viable cell numbers of HT-29 human colon cancer cells (IC50 = 10.7 +/- 0.3 mg/L), MDA-MB-231 human breast cancer cells (IC50 = 7.5 +/- 0.1 mg/L), and DU145 human prostate cancer cells (IC50 = 4.7 +/- 0.5 mg/L). HEGU augmented DOX-induced reductions in the viability of DU145 cells (15 +/- 1%). These results indicate that HEGU may potentially be an effective agent for the alleviation of DOX-induced cardiotoxicity.
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PMID:Hexane/ethanol extract of Glycyrrhiza uralensis licorice suppresses doxorubicin-induced apoptosis in H9c2 rat cardiac myoblasts. 1884 42

To investigate the possible effects of different beverages in the gastrointestinal tract on the sulfation of estrogen, which is a major hormone and prototype substrate for the human sulfotransferases (SULT), we analyzed the effects of these substances upon the sulfate conjugation of 17beta-estradiol (E2) in the human colon carcinoma cell line Caco-2. Sulfoconjugation activity toward E2 was measured by incubating 20 nM E2 with Caco-2 cells in the presence (5% (v/v)) of each beverage. Among the 35 beverages analyzed, four (aronia, blueberry, coffee, and peppermint) exhibited strong inhibitory effects on E2 sulfation within Caco-2 cells IC50 values ranging from 1.9 to 4.4% (v/v)). These active beverages also strongly inhibited the cytosolic estrogen SULT activity of Caco-2 cells in vitro (IC50 values ranging from 0.18 to 0.3% (v/v)). These inhibitory activities were extractable with ethyl acetate but not hexane or n-butanol, indicating that the molecules responsible are moderately lipophilic. Coffee was found to be the most potent inhibitor but the major constituents of this beverage, caffeic acid, caffeine, and chlorogenic acid, did not show any effects on estrogen SULT activity. Kinetic analyses further indicated that the mode of inhibition by coffee is competitive. A possible relationship between the inhibition of estrogen SULT activity by coffee in the gastrointestinal tract and the reported reduction of colon cancer incidence in women who consume coffee is discussed.
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PMID:Inhibitory effects of various beverages on the sulfoconjugation of 17beta-estradiol in human colon carcinoma Caco-2 cells. 1898 86


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