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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The gastrointestinal hormone gastrin has been shown to stimulate the growth of normal colonic mucosa. To examine for a possible role of gastrin in the proliferation of cultured colon tumor cells, we have studied the effects of two gastrin receptor antagonists, proglumide and benzotript, and of antibodies to gastrin. We find that proglumide (50% effective concentration, 2 to 5 mM) and benzotript (50% effective concentration, 0.4 to 0.8 mM) inhibit the monolayer growth of six human colon cancer cell lines. Addition of exogenous gastrin abrogated the growth-inhibitory effect of proglumide. The anchorage-independent growth of colon carcinoma cells was also inhibited by the two gastrin antagonists. Also, a dose-dependent increase in carcinoembryonic antigen secretion was observed upon treatment with proglumide and benzotript in three cell lines examined. Half-maximal inhibition of labeled gastrin binding was observed at concentrations of 0.4 mM benzotript and 8.6 mM proglumide. In addition, antigastrin antiserum added to HCT 116 cells adapted to growth in serum-free medium resulted in a concentration-dependent inhibition of cellular proliferation. These data suggest that gastrin may function as an autocrine growth factor in colon carcinoma.
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PMID:Antiproliferative effects of gastrin receptor antagonists and antibodies to gastrin on human colon carcinoma cell lines. 319 91

Colon carcinoma cells are first found as microscopic foci within benign tumors or adenomas. The carcinoma must invade the adenoma which protrudes into the colon lumen before it can infiltrate the bowel wall. A quantitative model for this process has been developed in tissue culture in which human colon carcinoma cells destroy cocultivated adenoma colonies. 43 adenoma colonies were assayed by cocultivation with carcinoma cells. Constitutive secretion of the urokinase form of plasminogen activator by carcinoma cells apparently plays some role in adenoma destruction as inhibition of this protease by the competitive inhibitor benzamidine reversibly inhibited adenoma destruction (p less than 0.01). Elevation of plasminogen activator secretion by addition of the tumor promoter 12-tetradecanoylphorbol-13-acetate significantly enhanced the destruction of colonies cultured from tubular adenomas with only mild dysplasia (p less than 0.025) and from villous, villotubular and tubular adenomas with moderate to severe dysplasia (p less than 0.0005).
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PMID:Tumor-promoter-enhanced destruction of noninvasive human benign colon tumor cells by cocultivated carcinoma cells. 323 26

Lentinan has been tested in a model of colon cancer in rats. Peritoneal carcinomatoses were induced in BDIX rats by i.p. injections of syngeneic cells isolated from a colon carcinoma, and established in a permanent cell line. The treatment consisted of five i.p. injections, 2 days apart, of 2 mg lentinan/kg at a concentration of 200 micrograms/ml. This was started on day 14 after tumor cell injection, when the rats bore numerous nodules of 1-5 mm. Lentinan significantly inhibited the growth of carcinomatoses. Eleven out of the 20 rats treated with the best lentinan therapy were tumor free at autopsy on day 42. Lentinan significantly increased the life span of carcinomatous rats. The half life following tumor cell injection was 42 days in the control and 70 days in the treated group. Four out of 10 treated rats were still alive on day 210. They were tumor free at autopsy, whereas all the controls died between the 40th and the 70th day. The effectiveness of lentinan was dependent on the number and frequency of the injections. A dose effect was obtained and a strong influence of the concentration was shown.
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PMID:Regression induced by lentinan, of peritoneal carcinomatoses in a model of colon cancer in rat. 323 40

A new monoclonal antibody designated FO23C5 against a protein component of carcinoembryonic antigen (CEA) has been developed. A xenograft system of human colon cancer was used to compare the intact monoclonal IgG with its fragments (Fab')2 and Fab) and with an established anti-CEA antibody (MAb35) and the antibody AUA1 raised against the colon carcinoma cell line. We demonstrate that FO23C5 compares well with the existing anti-CEA antibody and with AUA1, and that F(ab')2 fragments perform best in achieving optimal tumour to normal tissue ratios compared with intact IgG and Fab fragment.
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PMID:Radiolocalisation of an anti-CEA monoclonal antibody (FO23C5) and its fragments in a colon carcinoma xenograft model. 323 54

Leukocyte adherence inhibition-cell mediated immunity (LAI-CMI) studies were performed on leukocytes obtained from patients with various stages of breast cancer, colon carcinoma and lung cancer in order to monitor cell mediated immunity during tumor progression. In the presence of autologous serum, all patients with localized tumors showed positive LAI-CMI indexes (greater than 20%), while significant reduction of homologous tumor antigen recognition as measured by the LAI-CMI responses was observed in nearly all patients with Stage IV breast cancer, Duke C colon cancer and Stage III lung cancer. On substituting autologous serum with normal AB serum, leukocytes from patients with large tumor burdens responded to homologous tumor antigens. These results indicate the existence of organ-specific serum factor(s) which may mask the receptor sites on effector cells for tumor recognition. Patients with such serum blocking factor(s) showed significant increase of IgG immune complexes IgM, IgA and alpha-2-macroglobulins. Application of a protein A affinity column purification resulted in a major reduction of IgG and other immune globulins but not of alpha-2-macroglobulin. The blocking effects of autologous serum, however, were not completely abrogated by filtration on the protein A column, thus suggesting that SBF may be heterogeneous in nature and may occur in other serum protein fractions beside the immune globulins.
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PMID:Effector lymphocyte response to homologous tumor antigens in various stages of malignant disease as monitored by leukocyte adherence inhibition--cell mediated immunity (LAI-CMI). 328 Apr 78

Antibodies raised against tumour-associated antigens have been assessed for tumour selectivity using an indirect immunohistochemical peroxidase staining of formalin-fixed, paraffin-embedded tissue from colon carcinomas, colon polyps and normal mucosa. The following antibodies were used: 1) Unabsorbed polyclonal antibody to carcinoembryonic antigen (poly-CEA). 2) Monoclonal antibodies to CEA (mabs 3851 and 27). 3) Monoclonal antibodies to protein-bound carbohydrates (mabs C 216 and C 242) or to lipid- and protein-bound carbohydrates (C 50 and 19-9). These antibodies had been produced by hybridization of lymphocytes from mice, immunized with colon carcinoma cell lines or colon cancer tissue. All antibodies were used in one concentration only, preselected by initial titration experiments. No antibody was completely tumour-specific, but four antibodies, mabs 3851, 27, C 216 and C 242, showed statistically significant tumour selectivity. Using these antibodies, respectively 19, 19, 19, and 18 of 20 colon cancer were stained compared with 3, 4, 4, and 8 of 15 specimens of colon mucosa from normal controls. An increased frequency of staining was also noted in dysplastic polyps (statistically significant using mabs 3851 and C 216) and in dysplastic mucosa adjacent to a tumour (statistically significant using mabs 3851 and 27). The staining frequency of normal colon mucosa in cases of colon cancer did not differ from that in the normal controls. Poly-CEA and the anti-ganglioside mabs C 50 and 19-9 revealed no tumour selectivity. A pronounced goblet cell staining was seen using C 50, C 242 and 19-9.
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PMID:CEA and carbohydrate antigens in normal and neoplastic colon mucosa. An immunohistochemical study. 330 32

A 75-year-old woman evaluated for "drop attacks" 3 years after anterior resection for colo-rectal cancer developed hyponatremia associated with a morning cortisol of 5.7 micrograms/dl, a plasma adrenocorticotropic hormone level of 319 pg/ml, and an inadequate response to cosyntropin. Computed tomography scan demonstrated bilateral adrenal masses. Fine needle aspiration biopsy of the adrenals revealed adenocarcinoma, histologically similar to her previous colon carcinoma. Addison's disease secondary to isolated colon cancer metastases to the adrenals is rare. Our report represents the first antemortem histologically confirmed diagnosis of this entity. A review of the available literature is presented.
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PMID:Adrenal insufficiency. A rare initial sign of metastatic colon carcinoma. 330 24

Matched normal/tumor DNA pairs from sporadic colon carcinoma patients were examined for chromosome 5 allele loss using a probe for a functional gene (glucocorticoid receptor = GRL) locus. This locus maps (5q11-q13) close to one of two alternative sites recently reported for a constitutional deletion in a familial adenomatous polyposis (FAP) patient. Tumor-specific allele loss of at least 27% at GRL supports the hypothesis that both hereditary and sporadic forms of colon cancer result from mutations of the same gene. The proximity of the GRL locus to the region of 5q affected in FAP and the observed tumor-specific allele loss at this locus suggest that further research is needed regarding whether genetic alterations in the glucocorticoid receptor may be associated with colon carcinogenesis.
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PMID:Chromosome 5 allele loss at the glucocorticoid receptor locus in human colorectal carcinomas. 334 39

Pharmacological doses of pentagastrin or gastrin are known to stimulate cell proliferation in normal colonic epithelium but the growth-promoting effect of gastrin on colon carcinoma is still controversial. In this study morphological parameters were measured to study the effect of pentagastrin (240 micrograms/kg) on the cell proliferation kinetics in experimental tumours. Colon cancer was produced in rats by weekly injections (20 mg/kg b.wt.) of 1.2-dimethylhydrazine for 24 weeks. Tritiated thymidine was given after administration of pentagastrin or the control solution to the animals. 75% of the animals from the pentagastrin group and 66% of the controls had at least one colon cancer. Autoradiographs of the colonic tumors were performed and the percentage of labeled cells in the cancer cell population was determined after counting 4000 to 16,000 cancer cells per tumor. The labeling index for cancer cells in the pentagastrin-treated group (21.49 +/- 1.76%) was higher (P less than 0.01) than in the control group (14.76 +/- 0.66%). In a second study vincristine sulphate (1 mg/kg) was given to the animals 20 h after administering pentagastrin or the control solution. The percentage of arrested metaphases in the tumours was determined after counting 10,000 to 24,000 cancer cells per histological section. Pentagastrin increased (P less than 0.01) the mean metaphase index by 108% (4.9 +/- 0.44% vs 2.35 +/- 0.32%). These data indicate that cell cycle manipulation of colon cancer is possible with hormonal peptides.
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PMID:Stimulating effect of pentagastrin on cancer cell proliferation kinetics in chemically induced colon cancer in rats. 335 23

The authors generalize the experience with diagnostics and surgical treatment of 113 patients with colon carcinoma involving the adjacent organs and tissues. Extended radical operations were made on 70 patients (62.5%). The nearest results of the surgical treatment of such patients have shown that extended radical operations consisting in a removal of the colon segment with tumor as a single block with the involved adjacent anatomical structures are followed by inconsiderably higher lethality (12.8%) as compared with noncomplicated carcinoma of the colon.
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PMID:[Surgical treatment of cancer of the colon involving adjacent organs and tissue]. 338 4


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