Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007097 (carcinoma)
 152,788 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes in the glycosylation of asparagine-linked oligosaccharides have been shown in various tumor cells, including human colon cancer. Attempts were made to elucidate the difference in Asn-linked oligo-saccharides attached to lysosomal membrane glycoproteins isolated from sublines of human colon carcinoma exhibiting high and low metastatic potentials in nude mice. Lysosomal membrane glycoproteins (lamp) 1 and 2 were immunoprecipitated from the cells after labeling with radioactive sugars, and the glycopeptides prepared were fractionated by serial lectin affinity chromatography employing immobilized concanavalin A, Datura stramonium agglutinin, and tomato lectin. Comparison of Asn-linked oligosaccharides from the different colonic carcinoma cells revealed the following features. First, the highly metastatic carcinoma cells express more poly-N-acetyllactosaminyl side chains with branched galactose residues than cells with low metastatic potential. Second, sialylation is more significant in the highly metastatic carcinoma cells than in the poorly metastatic ones. Conversely, N-acetyllactosamine units are less fucosylated in the highly metastatic cells than in poorly metastatic cells. These structural changes were apparently caused by the increase in sialyltransferase and the decrease in alpha 1----3 fucosyltransferase in the highly metastatic cells. The results also suggest that highly metastatic carcinoma cells express more sialyl Lex structures at the termini of poly-N-acetyllactosaminyl side chains than poorly metastatic carcinoma cells. Further, highly metastatic cells were found to express more lamp-1 and lamp-2 on the cell surface. These results were found to be correlated to the increased expression of sialyl Lex structures with high affinity binding of anti-sialyl Lex antibody on highly metastatic cells. Increased expression of sialyl Lex in the poly-N-acetyllactosamines of the cell surface may contribute to the metastatic behavior of the cells, assuming that this structure can serve as a better ligand for selectins present on endothelial cells and platelets.
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PMID:Differential glycosylation and cell surface expression of lysosomal membrane glycoproteins in sublines of a human colon cancer exhibiting distinct metastatic potentials. 154 42

With the purpose of studying changes in the expression of glycoconjugate structures in nonmalignant and cancerous lesions of urothelium the lectins ConA, TKA, PNA, DBA, STA, LFA, UEA, MPA, RCA, LCA, GSA1, SBA, GSA2, WGA, PHA and Lot were tested in formalin-fixed, paraffin-embedded tissue sections of (1) cold biopsies from normal urothelium and bladder cancer of different grades (G1-G3) in humans, (2) normal transitional epithelium and N-butyl-N(4-hydroxybutyl)nitrosamine (BBN)-induced bladder cancer in animal experiments (Wistar rat), and (3) human transitional cancer cell line HT 1376. In human urothelium TKA and SBA were positive markers demonstrating positive staining reactions in all tumor grades without binding to normal epithelium. They stained also the human transitional carcinoma cell line HT 1376 (G3). In Wistar rats DBA, ConA, LCA, SBA, GSA2 and WGA had a specific affinity to BBN-induced carcinoma. Findings of positive lectin marker in transitional cell cancer may offer progress in diagnostics and therapy.
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PMID:Lectins in diagnosis of bladder carcinoma. 158 9

Image analysis was performed on 40 Feulgen-stained histologic samples and 48 Feulgen-stained cytologic preparations representing normal squamous epithelium and all grades of cervical lesions (from mild dysplasia to invasive carcinoma) in order to characterize the evolutionary progressive changes in cervical epithelial proliferative disease toward malignancy. Quantitative studies included the analysis of proliferative features, differentiation features, nuclear morphology and DNA content. The data obtained on the histologic sections showed that the various features, to a different extent, detected a gradual increase in phenotypic cellular disarrangements related to the progression of the cervical lesions toward malignancy--that is, the modifications to nuclear area, perimeter, DNA content, percentage of nuclei with nucleoli, nuclear/cytoplasmic ratio and percentage of cells with no membrane positivity for soybean agglutinin lectin were progressively greater, moving from normal epithelium and mild dysplasia toward infiltrating carcinoma. In particular, all the morphologic and histochemical features appeared to parallel a diploid reduction and the appearance of aneuploidy. The simultaneous evaluation of proliferation- and differentiation-related features, together with those of nuclear DNA content, showed two main successive preneoplastic lesions: one characterized by an increase in cell turnover without alterations in its organization and another by a true neoplastic disorder. The data obtained on sequential cytologic examinations showed that individual cell changes are detectable and seem basically to be characterized by the appearance of clusters of cells with somatic characteristics not observed in previous cytologic checks. From the results of our study, the cervical intraepithelial neoplasia (CIN) concept appears to be inaccurate. In fact, only CIN III (severe dysplasia/carcinoma in situ) lesions have the morphologic and proliferative alterations of true neoplasia. In contrast, CIN I and some cases of CIN II lesions lack these characteristics and seem to be properly classified as dysplasia, thus avoiding the term neoplasia, implicit in CIN. Moreover, the multivariate study of data sets of features related to the progressive somatic changes, both in histologically and cytologically studied cases, allows us to detect the steps of progression; they are marked by the appearance of cell clusters with qualitatively different phenotypic characters when compared to the cell populations from which they presumably arise. These results seem to provide a further argument against the CIN theory, which stresses the concept that progression is related only to a gradual numerical increase in an initially established phenotype with the characteristics of malignancy.
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PMID:Cytometric evidence that cervical intraepithelial neoplasia I and II are dysplasias rather than true neoplasias. An image analysis study of factors involved in the progression of cervical lesions. 159 Aug 97

Because the pulmonary alveolar space is both the site of gas exchange for respiration and a portal of entry for foreign antigen, immunologic interactions within that space must be meticulously controlled. Alveolar epithelial cells are ideally situated to play a role in immune regulation within the alveolar space. We have used A549 cells, a cell line that is derived from a human alveolar cell carcinoma and that has been used as a model for alveolar type II epithelial cells, to examine the potential role of alveolar epithelial cells in local pulmonary immune regulation. Medium conditioned by confluent monolayers of A549 cells suppressed proliferation by human peripheral blood mononuclear cells (PBMC) stimulated with lectin, anti-CD3 antibodies, calcium ionophore and phorbol ester, or in a mixed leukocyte reaction. PBMC that had been incubated in and then removed from A549-conditioned medium went on to proliferate normally. Because the suppressive effect was abrogated by heating or acidification and was not blocked by neutralizing antibody to transforming growth factor-beta 1, this effect could not be attributed to transforming growth factor-beta. The factor mediating this effect has an approximate molecular weight of 70,000 D by gel filtration chromatography. Nonalveolar, pulmonary carcinoma cell lines did not exert this immunosuppressive influence nor did the alveolar epithelial cells inhibit proliferation by the transformed, Jurkat, T-cell line. Cell cycle analysis demonstrated that PBMC exposed to A549 cell-conditioned medium failed to enter S phase after mitogen stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A factor secreted by a human pulmonary alveolar epithelial-like cell line blocks T-cell proliferation between G1 and S phase. 159 Oct 14

1. Perchloric acid-soluble fraction from liver metastases of pancreas carcinoma of a patient with blood group B, was subjected to a systematic affinity chromatography using Vicia unijuga lectin (VUA) and Arachis hypogaea anti-T lectin (PNA) as immobilized ligands and separated into three fractions, B-active glycoprotein fraction, serologically inactive glycoprotein fraction and glycoprotein (VP) fraction exhibiting reactivities for Vicia graminea lectin (VGA), VUA and PNA. 2. VGA- and VUA-binding (Vgu) glycoprotein with Thomsen-Friedenreich (T) activity which was isolated, in a high state of purity, from VP fraction by HPLC using Asahipak GS-710 column, was demonstrated to be a mannose-rich glycoprotein with mol. wt of 1492 kDa and contained 40.40% carbohydrate.
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PMID:Isolation and characterization of a Vicia graminea and Vicia unijuga lectins-binding (Vgu) glycoprotein with Thomsen-Friedenreich (T) activity from human liver metastases of pancreas carcinoma. 159 52

We have studied the cellular immune response that accompanies primary and metastatic brain cancers induced experimentally in rats by inoculation of RG-2 glioma and Walker 256 (W256) carcinoma cells, respectively. The inflammatory cell infiltrates were characterized with lectin histochemistry to visualize microglial cells and macrophages and with immunohistochemistry, using a panel of monoclonal antibodies, to detect major histocompatibility complex (MHC), lymphocytic, and macrophage antigens. The metastatic tumor was composed of a loose stroma with multiple, often large, necrotic areas, whereas the RG-2 glioma was composed of a dense collection of tumor cells showing only rare necrotic foci. Both tumor types were heavily infiltrated with microglia and/or macrophages, and these were positive for MHC Class II (Ia) antigens. Expression of MHC Class I antigens was absent from RG-2 glioma cells, but it was present in W256 metastatic carcinoma cells. The metastatic tumor was also characterized by a much heavier infiltrate of lymphocytes, as shown by the presence of cells positive for CD4, CD8, and leukocyte common antigens. These lymphocytic markers were absent from reactive microglia in the W256 carcinoma, whereas they were present in the RG-2 glioma. Polymorphonuclear leukocytes were seen only in the metastatic tumor. Our study delineates differences between the inflammatory cell infiltrates found in metastatic brain tumors and those found in primary brain tumors. The differences in cell composition and immunophenotype may indicate a more effective antitumor response in the metastatic tumor that could account for the observed tissue destruction.
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PMID:Inflammatory cell infiltrates vary in experimental primary and metastatic brain tumors. 161 93

The development of carcinoma was examined in male Wistar rats (n = 120) exposed to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the drinking water (83 micrograms/ml) for 16 weeks. After MNNG administration, rats were investigated by endoscopic observation, visualization of microvascular structure, and estimation of lectin binding sites. Changes of bile reflux to the stomach was observed endoscopically at 24 weeks as well as the development of gastric mucosal erosions. Protruding and expansive ulcerating carcinomas developed at 36 weeks and had a microvascular pattern similar to that of human adenocarcinoma. Estimation of lectin binding site and pattern was useful to evaluate the malignant potential of cell proliferation. We postulate that endoscopic observation is valuable in investigating the development of gastric carcinoma, and microvascular structure and lectin binding pattern may be useful to demonstrate the mechanism of growth of gastric carcinoma.
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PMID:Histopathological development of gastric tumors induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats. 162 81

Tetranectin (TN) is a human, plasminogen kringle 4 binding plasma protein with ubiquitous cellular distribution and lectin-like characteristics. By means of the peroxidase-antiperoxidase staining technique a polyclonal and a monoclonal antibody were used to demonstrate TN within the intracellular as well as the extracellular compartment of invasive breast carcinoma. Whereas cell associated TN was universal showing only quantitative differences depending of the growth pattern of the tumor, 78 of 133 tumors displayed TN extracellularly as well. The occurrence of this stromal TN immunoreactivity was closely associated with desmoplasia, recognized morphologically by an increase in fibroblastic cells and immunohistochemically by an intense staining for the connective tissue glycoprotein fibronectin (FN). Benign breast tissue displayed a universal, intense cytoplasmic but no extracellular reaction for TN, with the exception of rare foci of granulation tissue and around dilated cysts. Functional studies have shown that human embryonal lung fibroblasts increase their release of TN to the growth medium upon stimulation. The presence of TN extracellularly within fibroblast-rich foci of desmoplasia (and granulation tissue) suggests that a similar increased release of the protein takes place in vivo during active states. Desmoplasia has been found to have a protective effect on tumor cell propagation and metastasis in a murine model. The molecular interactions, which are responsible for this effect, are undoubtedly complex. However, TN may, by its specific binding to kringle 4 of plasminogen and its high affinity for sulphated polysaccharides, add to the understanding of how plasminogen activation is modulated at the local extracellular level.
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PMID:Differences in tetranectin immunoreactivity between benign and malignant breast tissue. 165

A comparative study was undertaken among mucoepidermoid carcinoma, adenoid cystic carcinoma, acinic cell carcinoma and normal salivary glands using lectin affinity histochemical method. It was found that the positive rate was highest in mucoepidermoid carcinoma (P less than 0.05); Among the 4 kinds of lectins used PNA and UEA had different distributions and contents in cancer and control groups (P less than 0.05). The mucoid substances in the cancer tissue were mixed mucin, similar to those in the normal salivary gland. However, there was more mixed mucin in the former than in the latter. This method is useful in diagnosis of salivary gland carcinoma. The relation of glucoprotein content on the cancer cell surface and carcinogenesis is discussed.
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PMID:[Preliminary study on lectin affinity histochemistry for diagnosis and histogenesis of salivary gland carcinoma]. 165 18

The mucin alterations associated with the progress of cellular atypia of the colorectal mucosa were investigated by light and electron microscopy using lectin-histochemical technique with DBA and PNA. The samples showing positive staining in the more than one-third areas of the colonic epithelial mucosa were scored as positive reaction. The DBA positive reaction was found 100%, 95.8% and 45.7% in the normal mucosa, adenoma and carcinoma, respectively. On the other hand, the PNA positive cases increased with the grade of malignancy; 18.2%, 58.5% and 97.1% respectively. The DBA binding sites were found in the mucin of the goblet cells of the normal and adenomatous epithelia. The PNA positive sites were localized in the supranuclear portion of the normal mucosa and adenoma while in the epithelia of the carcinoma the PNA positive areas were found in the intraglandular substance and cell apex. With the electron microscopy the PNA binding sites were detected in the cis cistern of Golgi apparatus in the normal and adenomatous epithelia and in the apical membrane in the epithelia of the carcinoma. It is suggested that the PNA binding activity is a useful marker to detect the adenomas with the high risk of malignant transformation.
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PMID:[A study of binding sites of lectins in colorectal adenomas and carcinomas: the optical and electron microscopical findings]. 165 99


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