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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal antibodies (MAbs) 123C3 and 123A8 generated against a membrane preparation of a small cell lung carcinoma (SCLC) specimen recognize not only SCLC and bronchial carcinoids but also a significant portion of non-small cell lung carcinomas (non-SCLC) of various histological types. Together with 13 other monoclonal antibodies, which show preference for SCLC, they have been ranked as SCLC cluster 1 (SC-1) Mabs. In this study we show that SC-1 MAbs are directed against a restricted number of epitopes, and that SC-1 MAbs and a polyclonal antiserum directed against the neural cell adhesion molecule (NCAM) recognize identical glycoproteins, indicating that SC-1 antigens are closely related to or identical with NCAM. Long polysialic acid units composed of alpha-(2,8)-linked N-acetylneuraminic acid units, which in mammals are found exclusively on NCAM, were present on SC-1 antigens in SCLC. This provides further evidence that SC-1 MAbs recognize NCAM. The SC-1 antigens in the SCLC cell line H69 were present in two forms, NCAM-containing alpha-(2,8)-polysialic acid units identified by antiserum 735, the NCAM-H form, and the less sialylated NCAM-L form. The NCAM-H form consisted of diffusely migrating sialoglycoproteins with a molecular weight of 200,000-250,000, which resolved after neuraminidase treatment into two proteins with molecular weights of 140,000 and 180,000. Since the NCAM-H form is expressed in the lung tumor type with a poor prognosis, our results suggest that NCAM might be implicated in the invasive behavior of these NCAM-positive lung tumors.
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PMID:Expression of neural cell adhesion molecule-related sialoglycoprotein in small cell lung cancer and neuroblastoma cell lines H69 and CHP-212. 215 50

GM2 ganglioside is a common cell surface constituent of human melanoma and other tumors of neuroectodermal origin, and vaccination with GM2 ganglioside results in high levels of anti-GM2 antibodies in patients with melanoma. Lymphocytes from a GM2-vaccinated patient (VS) were transformed by Epstein-Barr virus and tested for production of antibodies with reactivity for GM2-positive tumor cells. A high percentage of antibody-producing B cells was detected, but antibody reactivity was generally lost during culture expansion. Two cultures, however, remained stable for antibody productivity and one was used to develop a stable hybrid line with mouse myeloma. The monoclonal antibody (designated 3-207) derived from patient VS has dual specificity for GM2 and GD2, despite the fact that only GM2 antibody could be detected in the patient's serum. Monoclonal antibody 3-207 shows high-titered reactivity with a range of melanoma, astrocytoma, neuroblastoma, and leukemia cell lines, cells with prominent cell surface expression of GM2 and GD2. The cell surface reactivity of monoclonal antibody 3-207 was not abolished by treatment of target cells with neuraminidase, as the enzyme converted GD2 to GM2, which was still detected by monoclonal antibody 3-207.
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PMID:Human monoclonal antibody with dual GM2/GD2 specificity derived from an immunized melanoma patient. 215 45

Cell surface glycoconjugate expression of endothelial cells in canine cutaneous hemangiomas and hemangiosarcomas was compared to normal cutaneous endothelial cells using eight different lectins (with and without neuraminidase pretreatment) in an indirect immunoperoxidase technique. Direct comparison of lectin binding pattern of neoplastic endothelial cells with adjacent normal endothelial cells revealed minor changes in the binding intensity of several lectins (enhanced: Wheat germ agglutinin [WGA]; reduced: Griffonia simplicifolia-I [GS-I], Ricinus communis agglutinin-I [RCA-I], Soybean agglutinin after neuraminidase pretreatment [Neu-SBA], and Wheat germ agglutinin after neuraminidase treatment [Neu-WGA]). Neoplastic endothelial cells in some tumors exhibited varying binding of Ulex europaeus agglutinin-I (UEA-I; not binding to normal canine endothelial cells) and no Soybean agglutinin (SBA) binding (variably binding to normal endothelial cells in small cutaneous vessels). Lectin binding of neoplastic cells was rather heterogenous within one tumor compared to the uniform binding pattern of normal endothelial cells. These lectin binding studies demonstrate the phenotypic heterogeneity of neoplastic endothelial cells, indicating changes of cell surface glycosylation during neoplastic transformation.
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PMID:Phenotypic characterization of normal and neoplastic canine endothelial cells by lectin histochemistry. 218 54

The Thomsen-Friedenrich (TF) antigen is a precursor structure of MN blood group antigens and is also expressed by about 90% of human carcinomas. The immunodominant group of TF antigen [beta-galactosyl(1-3)-alpha-N-acetylglactosamine] is present in cryptic form in normal RBC and is revealed by neuraminidase treatment. A murine monoclonal antibody (Mab 49H.8) developed against neuraminidase treated human RBC was reactive against a variety of human tumors. We have characterized the human tumor associated TF antigen detected by this antibody from a human transitional bladder carcinoma cell line (647V), a human colon adenocarcinoma cell line (LS174T), and a pleural effusion fluid of a breast adenocarcinoma patient (PE 89). A heterologous sandwich radioimmunoassay for TF antigen was developed using Mab 49H.8 as the catcher and 125I-peanut agglutinin as the probe. Detergent extracts of 647V and LS174T cells, media conditioned by culturing these cells, and PE 89 were shown to contain the antigen by this assay. The specificity of the antigen capture by Mab 49H.8 in this assay was demonstrated by its selective inhibition by nitrophenyl-beta-D-galactoside, phenyl-beta-D-galactoside, and a TF hapten. Preliminary studies on TF antigen in serum samples using this assay showed that about 53.7% of the carcinoma samples contained an antigen concentration greater than 200 units/ml whereas for 90.9% of the normal samples the antigen concentration was below 200 units/ml. These studies demonstrated that the TF antigen is shed by the tumor cells both in vitro and in vivo. The TF antigen was sensitive to treatment with alkali (0.1 M NaOH for 5 h at 37 degrees C) and periodate (10 mM sodium periodate for 1 h at room temperature), was resistant to acidic pH (50 mM acetate buffer, pH 4.5, for 5 h at 37 degrees C), and could be extracted with perchloric acid (0.6 M for 1 h at 4 degrees C). The antigen was shown to be a high molecular weight glycoprotein (Mr greater than 1,000,000) by gel filtration chromatography. The density of the antigen was estimated to be about 1.35 g/ml by cesium chloride density gradient centrifugation. The antigen could be isolated from conditioned media by a combination of affinity chromatography and gel filtration with an overall purification of about 61,432-fold and a final recovery of 53.2%.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Analysis of human tumor associated Thomsen-Friedenreich antigen. 219 17

Spleen cells from inbred Biozzi mice, immunized against the human breast cancer cell line T47D, were fused with murine myeloma SP2O cells to generate monoclonal antibodies. One of these, 1BE12, of IgM isotype, reacted with five of six human breast tumor cell lines, while no binding was detectable with normal lymphocytes, RBC, or fibroblasts. The antigen recognized by monoclonal antibody 1BE12 was localized on the surface of T47D and MCF7 cells and was detected in cell-free supernatants of cultures. The antigen was found also on the surface of milk secretory cells. Immunohistochemical staining of frozen and paraffin-embedded sections of human tissues showed apical polarized reactivity in normal breast glands, while in all breast cancers staining was either cytoplasmic or membranous and heterogeneously distributed. Immunostaining was also observed in some other normal epithelia, including salivary gland, gastroduodenal mucosa, exocrine pancreas, and cervix. The antigen was not detectable in secretory endometrium, whereas proliferative endometrium was strongly stained. Colon carcinoma, and cancers of the bladder and endometrium were strongly reactive. No staining was detected in melanoma, lymphoma, mesothelioma, non-small cell lung carcinoma, and thyroid, renal, and ovarian carcinomas. Lectin absorption of MCF7 membrane extracts reduced 1BE12 binding. A large reduction in 1BE12 reactivity was observed after digestion of T47D and MCF7 membrane extracts with proteases. Treatment with sodium periodate resulted in complete loss of antigenicity, while neuraminidase treatment did not affect 1BE12 binding. These findings suggest that the 1BE12 epitope is expressed on the carbohydrate moiety of a glycoprotein and does not contain sialic acid. Immunoblotting of the perchloric acid-soluble fraction of MCF7 membrane extracts after electrophoresis in 1% agarose detected the antigen as a high molecular weight species (Mr greater than 900,000). The antigen was purified by perchloric acid extraction of MCF7 membrane preparations followed by affinity chromatography on 1BE12 antibody coupled to Sepharose-4B and gel exclusion fast protein liquid chromatography. No reactivity of the purified material was found with monoclonal antibodies directed against human milk fat globule membrane-associated mucins HMFG1 and DF3.
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PMID:Characterization and distribution in human tissues of a glycoproteic antigen defined by monoclonal antibody 1BE12 raised against the human breast cancer cell line T47D. 222 61

A33 is a mouse immunoglobulin G2a (IgG2a) monoclonal antibody (mAb) that detects a heat-stable, protease- and neuraminidase-resistant epitope. The antigen is homogeneously expressed by virtually all colon cancers and in the colon mucosa but not other epithelial tissues. The biodistribution and imaging characteristics of iodine-131 (131I)-mAbA33 were studied in colorectal carcinoma patients with hepatic metastases. Antibody labeled with 2 to 5 mCi of 131I was administered intravenously (IV) 7 to 8 days before surgery at five dose levels, ranging from 0.2 mg to 50 mg, with three or more patients entered at each dose level. In addition, three patients received 2 mg 131I-mAbTA99 (an isotype-matched control mAb) together with 125I-mAbA33. Evaluation included whole-body imaging with a gamma camera, technetium-99 (99mTc)-human serum albumin blood pool scans, liver/spleen scans, abdominal computed tomographic (CT) scans, hepatic arteriograms, antibody pharmacokinetics, and assessment of antibody distribution in biopsied malignant and normal tissues. Selective mAbA33 localization to tumor tissue was demonstrated in 19 of 20 patients, and external imaging correlated with surgical inspection, pathologic examination, and tissue radioactivity. One week after antibody administration, tumor:liver ratios ranged from 6.9:1 to 100:1 and tumor:serum ratios from 4.1:1 to 25.2:1. 99mTc-albumin blood pool studies showed that liver metastases were hypovascular, emphasizing the selective localization of mAbA33 despite poor tumor-blood flow. Control mAbTA99 studies showed mAbA33 localization was antigen-specific; tumor:liver ratios were 2.3- to 45-fold higher for specific antibody. In metastatic lesions, radioisotope was localized primarily in the viable periphery; however, even the necrotic tumor core concentrated specific antibody. External imaging showed isotope visualization in some patients' large bowel; whether this represents specific antibody uptake or gastric iodine secretion is unclear.
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PMID:Quantitative analysis of antibody localization in human metastatic colon cancer: a phase I study of monoclonal antibody A33. 223 Aug 77

Naturally occurring cancer in companion animals parallels cancer in man more closely than does experimentally induced cancer in inbred laboratory animals. In dogs and cats, as in man, a role for immune responses is indicated in the development of tumors. A survey is presented based on the literature and our own studies concerning the immunological and immunotherapeutic aspects of canine and feline mammary neoplasia. In dogs bearing mammary neoplasms, circulating immune complexes appear to play a negative role in the generation of effective antitumor immune responses. The functional role of peripheral blood lymphocytes and tumor-infiltrating lymphocytes in dogs and cats with mammary tumors is not yet fully established. No tumor antigen responsible for humoral or cellular responses has yet been identified. Extracorporeal perfusion of serum of dogs with mammary tumors and subcutaneous administration of mitomycin- and neuraminidase-treated autologous tumor cells are associated with improved prognosis. The opposite was true for i.v. treatment with BCG or Corynebacterium parvum vaccine in our study, in contrast to a previous report. A number of other treatment modalities in cats and dogs with mammary carcinomas failed to induce tumor regression. Canine and feline mammary carcinomas are good candidates for modern immunotherapeutic approaches.
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PMID:Immunological aspects of mammary tumors in dogs and cats: a survey including own studies and pertinent literature. 226 85

We used 5 syngeneic murine tumour systems for studying quantitative lectin surface binding of intact viable tumour cells. We also investigated, for 3 of the tumours, whether the lectin binding sites were susceptible to proteolytic enzyme (pronase) or neuraminidase treatment. There were significant differences between two of the tumour lines in the binding of wheat germ agglutinin (WGA), concanavalin A (ConA). peanut agglutinin (PNA), soybean agglutinin (SBA) and Ulex europeus agglutinin (UEA). There were also variations in lectin binding between the other tumor lines, but these differences were not statistically significant. Lectin binding showed no evident relationship to the malignancy or the metastasis-forming capacity of the respective tumour cell line. Proteolytic treatment, which drastically affects intravenously induced experimental metastasis formation by one of the tumours, caused a decreased binding of SBA, ConA and WGA. Neuraminidase treatment increased both PNA and SBA binding in three different cell lines, presumably by removing sialic acid masking D-galactose and N-acetyl-D-galactose-amine groups.
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PMID:Lectin binding in murine tumour lines with different malignant characteristics. Effect of enzyme (pronase, neuraminidase) treatment on lectin labelling. 226 85

In 31 transitional cell cancer (TCC) tissues and 5 normal bladder mucosae (NBM), we compared the results of flow cytometry (FCM) and immunohistochemical examination in evaluating the expression of Thomsen-Friedenreich antigen (T-Ag) using a monoclonal antibody. On immunohistochemical examination, 14 (45%) cancer tissues showed T-Ag, while 7 (23%) cancer tissues and all NBM showed only cryptic T-Ag, which was detected only after neuraminidase treatment. Ten (32%) high grade cancer tissues showed neither T-Ag nor cryptic T-Ag. ON FCM the T-Ag positive cells (TPC) and the T-Ag positive cells after neuraminidase treatment (nTPC) were counted in fresh cell suspensions. FCM was more sensitive than immunohistochemical study in detecting T-Ag. Additionally, FCM revealed that some tumors had both T-Ag and cryptic T-Ag at the same time. The ratio of nTPC to TPC was well correlated with the stage or grade of the tumor and may be a more reliable marker of TCC than the expression of T-Ag assessed by immunohistochemical techniques.
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PMID:Flow cytometric evaluation of Thomsen-Friedenreich antigen on transitional cell cancer using monoclonal antibody. 233 79

It has been suggested that peanut agglutinin (PNA)-binding sites in benign and malignant tissues were quite different. To clarify the difference of PNA-binding sites between benign and malignant ependymoma, PNA-binding sites are investigated on the surface membrane of tissues from benign and malignant ependymomas and cultured ependymoma cells. In four of five malignant ependymoma cases, PNA binding occurred in a diffuse cell membrane fashion or granular intracytoplasmic fashion without neuraminidase treatment. On the other hand, PNA binding was observed without neuraminidase treatment in only two of eight benign ependymoma cases. After neuraminidase treatment, all of our benign and malignant ependymoma cases evidenced PNA binding. PNA binding was clearly evident on the cell membrane of ependymoma cells which were able to express organotypic structures, that is, to form ependymal rosettes after neuraminidase treatment. Normal rat ependymal cells showed PNA binding only after neuraminidase treatment. These findings suggest that the masking of PNA-binding sites of ependymoma cells by sialic acid may be correlated with tumor cell differentiation.
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PMID:Localization and significance of peanut agglutinin-binding sites on ependymoma cells. 236 Apr 9


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