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)

Peanut lectin (PNA) has a specificity for the disaccharide beta-D-Gal-(1 leads to 3)-D-GalNac which is the purported antigenic determinant for the T blood group antigen (TAg). This TAg is considered the immediate precursor of the MN blood group substance. In normal colonic epithelium, PNA binds to the supranuclear (stalk) portion of epithelial cells. This corresponds to the detection of beta-DGal-(1 leads to 3)-D-GalNac in nascent oligosaccharide chains in the Golgi cisternae prior to addition of terminal sialic acid. Colonic carcinomas bind PNA in the "region" of the glycocalyx or in the apical portion of the cell, which represents incomplete glycoprotein synthesis. Eighty-two percent of tubular adenomas, 80% of villous adenomas, and 91% of adenomas with in situ cancer expressed PNA in a supranuclear distribution, reminiscent of normal colonic epithelium. This stalk distribution was seen in goblet cells. Twenty-five percent of tubular adenomas, 43% of villous adenomas and 60% of adenomas with in situ cancer (adenoma portion) expressed PNA in an apical cytoplasmic and/or glycocalyx pattern among nonmucinous columnar cells. In 80% of the cases, the in situ cancer itself expressed PNA in an apical cytoplasmic and/or glycocalyx pattern. Fetal and most colon cancer cells fail to produce mucin goblets and make incomplete glycoproteins. The cytologic localization of TAg by PNA corresponds to the cells' ability to produce mucin goblets. Most adenomas consist of goblet cells, localize TAg to the stalk, and probably make complete MN glycoprotein as does normal colonic epithelium. However, in adenomas, nonmucinous columnar cells localize TAg to the apical cytoplasm and/or glycocalyx region and represent incomplete blood group glycoprotein synthesis.
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PMID:Peanut lectin-binding sites in polyps of the colon and rectum. Adenomas, hyperplastic polyps, and adenomas with in situ carcinoma. 665 97

Lectins linked to fluorescein were used as carbohydrate probes to examine the goblet cell mucin and epithelial cell surface glycoconjugate alterations in an experimental rodent model of colonic neoplasia induced with parenteral 1,2-dimethylhydrazine dihydrochloride. Lectins derived from Triticum vulgare (WGA), Ricinus communis (RCA1), and Limulus polyphemus (LPA) showed reduced labeling of goblet cell mucin in these tumors, while binding with peanut lectin from Arachis hypogaea (PNA), a lectin ordinarily failing to bind to mucin in normal colon, was positive. In addition, RCA1 and LPA showed increased cell surface labeling of neoplastic epithelial cells. Finally, alterations were observed in lectin binding to "transitional" colonic mucosa adjacent to colonic tumors from carcinogen-treated rats. These findings indicate that significant alterations in both membrane and mucin glycoconjugates occur in colonic tumors and mucosa adjacent to tumors in a chemically induced experimental animal model of human colon cancer.
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PMID:Lectin histochemistry of 1,2-dimethylhydrazine-induced rat colon neoplasia. 668 37

A patient with carcinoma of the large bowel who presented with a subphrenic abscess is reported. This case emphasizes two important facts relating to colonic cancer in childhood: (i) premalignant disease of the large bowel is no prerequisite for the development of colonic cancer; and (ii) in childhood this disease is characterized by a fulminating course and high mortality. In about 50% of cases the tumour is of the signet ring or mucin-producing type, which explains the grave prognosis.
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PMID:An unusual presentation of carcinoma of the colon in a child. A case report. 671 Feb 73

Malignant tumors shed large numbers of cells into the circulation, only a small fraction of which actually produce distant metastases. The cells comprising these tumors may be heterogeneous in many respects including their biological behavior. Inasmuch as colonic epithelial cells secrete mucins that reflect the state of cell differentiation, and differences in mucin structure may be detected by selective lectin binding, we used fluorescein isothiocyanate-conjugated lectins and fluorescence microscopy to analyze mucins secreted by primary colon cancers and metastases. In this way we hoped to determine whether differences exist in the glycoconjugates produced by metastatic and nonmetastatic cell populations. Out studies demonstrated that, in a given primary cancer, the mucin produced differed from that made by its metastases. Thus the vast majority of cells in primary tumors produced mucin that was specifically labeled by fluorescent peanut agglutinin (14 of 16 tumors). In contrast, 72% (37 of 51) of metastatic tumors produced mucin that did not bind peanut agglutinin (p less than 0.001). Colon cancer cells with high metastatic potential may therefore produce mucins that lack an exposed oligosaccharide receptor for this lectin.
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PMID:Characteristics of colorectal carcinoma cells with high metastatic potential. 672 53

Cells of colonic carcinoma line HT-29, cultured over more than 170 generations and extensively used in immunological studies of patients with colorectal tumours, still express several immunologically valuable characteristics presumably present since its inception. The cell line can induce a poorly differentiated adenocarcinoma in the nude mouse, it has human antigenic characteristics, it expresses blood group A antigen, and produces a colon-specific mucin and CEA, though not colon cancer-specific mucin (CCM). It remains useful as a target for in vitro testing of anti-tumour immunoreactivity in colorectal cancer patients.
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PMID:Persistence of organ- and iso-antigens in vitro in a long-term culture cell line of colonic carcinoma. 676 88

During a 5-year period colon tumors induced by 1,2-dimethylhydrazine dihydrochloride treatment in NMRI mice were transplanted sc into isologous mice to obtain transplantable tumor lines that might serve as experimental models for human colon cancer. The resultant 17 serially transplantable tumor lines were adenocarcinomas varying in degree of differentiation and mucin production. Two of the lines passaged for 5 years and used in chemotherapy studies have shown histologic progression toward dedifferentiation with concomitant acceleration of growth rate.
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PMID:Some biological characteristics of transplantable lines of mouse adenocarcinomas of the colon. 692 51

The binding of fluorescein isothiocyanate (FITC)-conjugated lectins to mucin in the human colon was studied by using fluorescence microscopy. In normal mucosa, lectins that preferentially bind to exposed N-acetyl-galactosamine residues (Dolichos biflorus agglutinin and soybean agglutinin) bound selectively to the goblet cell mucin of well-differentiated cells in the upper colonic crypt. By contrast, lectins that require exposed non-reducing galactose residues for binding (Ricinus communis agglutinin1 and Bauhinia purpurea agglutinin) preferentially labeled the mucin of less-differentiated goblet cells located in the lower portion of the colonic crypt. The lectin derived from Arachis hypogaea (peanut agglutinin) has a high affinity for a carbohydrate structure not normally exposed in human tissues. This lectin did not label the goblet cell mucin in the normal colon. However, the mucin was labeled in all 21 colon cancer specimens examined. Additionally, the nonmalignant epithelium immediately adjacent to colon cancer (termed "transitional mucosa") also contained goblet cell mucin that was labeled by FITC-peanut agglutinin. Three conclusions may be drawn from the selective binding characteristics of FITC-lectins to colonic mucins. First, an alteration in the exposed, nonreducing carbohydrate residues occurs in human colonic mucin during the process of goblet cell differentiation. Second, an exposed carbohydrate structure that is not normally present in human tissues is expressed in the mucin produced by malignant colonic epithelium. Third, the presence of the cancer-associated carbohydrate structure in the mucin of transitional mucosa suggests that this tissue may be in the process of early malignant transformation.
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PMID:Alterations in human colonic mucin occurring with cellular differentiation and malignant transformation. 695 52

Using synthetic peptides 60,80, and 105 residues long, corresponding to 3, 4, and 5.25 tandem repeats of human mucin MUC-1 protein core, as antigens in a solid-phase enzyme-linked immunosorbent assay, we screened sera from 24 breast cancer patients, 10 colon cancer patients, and 12 pancreatic cancer patients, at various stages of disease, for the presence of mucin-specific antibodies. The 105-residue peptide was superior in allowing detection of high levels of anti-mucin antibodies in 10.9% of sera in each cancer group. Another 4.3% showed intermediate reactivity. Lower levels of detection were achieved with the 80-residue peptide, and no specific reactivity was detectable with the 60-residue peptide. Anti-mucin antibodies were previously undetectable when this assay was performed with purified whole mucin or short synthetic peptides. The presence or absence of antibody did not correlate with the levels of circulating mucin or stage of disease. One highly reactive serum sample was used to identify more precisely the epitope on the long synthetic peptide to which the reactivity was directed. The reactivity of this serum specific for the 105-residue peptide was blocked by a 9-residue peptide from the NH2-terminal region of the 20-residue tandem repeat containing the previously identified immunogenic epitope APDTRP. Another 9-residue mucin peptide, from the COOH-terminal region of the tandem repeat which does not contain the APDTRP epitope, had no effect. All the mucin-specific reactivity was found to be of the IgM isotype, indicating a helper T-cell-independent response, unusual for an antibody against a peptide epitope, but not unexpected for tandemly repeated epitopes.
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PMID:Humoral immunity against a tandem repeat epitope of human mucin MUC-1 in sera from breast, pancreatic, and colon cancer patients. 751 93

The antigen reacted with mAb B72.3 is tumor associated glycoprotein 72 (TAG-72). It has been shown that TAG-72 has good specificity, and it can bind to TAG-72 expressed in great majority of tumors. We have prepared 2 monoclonal antibodies, named 72-45 and 72-142, against epitopes on TAG-72 antigen different from those reacted with B72.3. The results shown that both antibodies did not react with normal adult and fetus tissues but sweat and sebaceous gland and epithelial cells of small intestine. The mAb 72-45 gave a 100% (20/20) positive reaction in colon cancer and 80% (24/30) positive in lung adenocarcinoma. The mAb 72-142 showed a 40.5% (9/20) positive reaction in colon cancer and 79.5% (27/34) positive in lung adenocarcinoma. The antigenic epitopes to which mAb 72-45 directs is carbohydrate and those to mAb 72-142 is also carbohydrate, but also related to sialo-acid mucin in molecular structure.
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PMID:[Preparation and identification of monoclonal antibodies against different epitopes on TAG-72 antigen]. 751 44

An 80-year-old man, who had been treated for colon cancer 25 years ago, presented with gross hematuria. Rectal examination revealed a soft nodule in the right lobe. The serum prostatic specific antigen (PSA) was elevated to 5.2 ng/ml, while prostatic acid phosphate (PAP) was normal. Transrectal ultrasound revealed a hypoechoic mass in peripheral zone of the prostate and dilated seminal vesicle. A needle biopsy of the prostate showed mucinous adenocarcinoma. Under the diagnosis of prostatic tumor with seminal vesicle involvement, radical prostatectomy was performed. Histological findings showed organ confined cancer, of which most was composed of extracellular mucin lakes. Immunohistochemical study revealed the tumor cells positive for PSA and PAP. Mucinous adenocarcinoma of the prostate has been known to be clinically different from non-mucinous adenocarcinoma, in that the former is insensitive to hormonal therapy, is rarely associated with elevated PAP and rarely metastasize to the bone. But our analysis of the literatures is Japan showed no significant difference clinically between mucinous and non mucinous prostatic adenocarcinoma. However mucinous adenocarcinoma with signet ring cell rarely responds to hormonal therapy, which should not be classified to true mucinous adenocarcinoma in the current criteria. True mucinous adenocarcinoma could be a variant of prostatic adenocarcinoma, which is peripheral origin and should be treated like non-mucinous adenocarcinoma.
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PMID:[Mucinous adenocarcinoma of the prostate. A case report and analysis of the literature]. 752 49


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