Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mammary tumor cell growth factor(s) has been identified in extracts of platelets from both male and female rats, as well as in extracts prepared from pooled outdated human platelets. When assayed by the growth promotion of MTW9/PL rat mammary tumor cells in culture, platelet extracts alone were able to support growth 50--75% as well as whole serum. The mitogenic activity from crude human platelet lysates was shown to be trypsin sensitive, relatively stable to extremes of pH, labile to heat treatment at 70 degrees, non-dialysable, ammonium sulfate precipitable, not removed by 56 degrees charcoal treatment, and of apparent molecular weight of 30,000 to 50,000 daltons as estimated by G-100 Sephadex chromatography. The platelet derived mammary growth factor activity was not replaced or potentiated by thrombin or known hormones and growth factors such as prolactin, insulin, 17-beta-estradiol, progesterone, hydrocortisone, L-thyroxine, and mouse epidermal growth factor. The experimental report demonstrates that platelets are a rich source growth factor activity for rat epithelial mammary tumor cells, and that the activity appears to be a polypeptide(s) different from other mitogenic activities known to influence growth of mammary tissue.
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PMID:Platelet derived growth factor(s) for a hormone-responsive rat mammary tumor cell line. 3 Jul 82

Heat-labile enterotoxin (LT) produced by a human strain of enterotoxigenic Escherichia coli (286C(2)) was purified to homogeneity from pH extracts of fermentor-grown cells by ultrafiltration, (NH(4))(2)SO(4) fractionation, hydrophobic chromatography on norleucine-Sepharose 4B, hydroxylapatite chromatography, and Bio-Gel P-150 filtration. Purified LT preparations exhibited biological activity comparable to that of cholera toxin in four bioassays specific for the two enterotoxins (Y-1 adrenal tumor cells, Chinese hamster ovary cells, pigeon erythrocyte lysates, and skin permeability test). The overall yield of LT protein was 20%, which represented a 500-fold purification over pH extracts. A native molecular weight of 73,000 was determined by gel electrophoresis. The toxin dissociated upon treatment with sodium dodecyl sulfate, pH 7.0, into two components with molecular weights of 44,000 and 30,000. Purified LT preparations were remarkably stable over a wide range of storage conditions, temperatures, and pH's. The biological activity was increased by incubation with trypsin and completely destroyed by pronase and proteinase K, whereas deoxyribonuclease I, ribonuclease, and phospholipase D had no effect. The amino acid composition of purified LT was quite different from that of cholera toxin. Neither carbohydrate nor lipopolysaccharide was present in purified preparations. The purification scheme appeared applicable to LT produced by other human and porcine enterotoxigenic strains, but reflected the amount of LT produced by each strain. These data show that LT and cholera toxin share many common chemical and physical properties, but must be purified by different techniques.
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PMID:Purification and chemical characterization of the heat-labile enterotoxin produced by enterotoxigenic Escherichia coli. 3 93

Nervous system tissues from a number of patients with idiopathic neurological disorders were examined for biochemical evidence of RNA tumor virus infection. RNase-sensitive DNA polymerase activity was found in a cytoplasmic particulate fraction from two patients with Guamanian amyotrophic lateral sclerosis (ALS) but not in brains from two normal U.S. individuals. The buoyant density of the enzyme-containing fraction was 1.16-1.18 g/ml and could be converted to a denser region of the gradient (1.24 g/ml) by treatment with the nonionic surfactant, Sterox. The cation and detergent requirements for the endogenous RNase-sensitive DNA polymerase reaction were determined. The early (5 min) endogenous reverse transcriptase product was analyzed by cesium sulfate gradient centrifugation. RNase- and heat-sensitive RNA-DNA hybrids were detected in the product analysis of two ALS, one Parkinsonism-dementia (PD) brain, and two brains from asymptomatic Chamorros but not in brains from normal U.S. individuals and a number of patients with neuro-psychiatric disorders. The DNA product was a 4.5S heteropolymer that hybridized more extensively to RNA extracted from the enzyme-containing pellet from PD brain as compared to a similar fraction from normal U.S. brain. The DNA product appeared to be unrelated to Rausvher or visna virus 70S RNA as determined by RNA-[-3H]DNA hybridization.
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PMID:RNA-instructed DNA polymerase activity in a cytoplasmic particulate fraction in brains from Guamanian patients. 4 90

The structure and antigenic characteristics of a human k, IgG myeloma protein that formed half-molecules were analyzed. Most of the myeloma protein found in the patient's serum and urine consisted to two chain 4.3S half-molecules. A small amount of four chain 7S myeloma protein was, however, found in the serum and was apparently formed by the same clone of tumor cells. Polyacrylamide gel electrophoresis in 8 M urea and 1% sodium dodecyl sulfate and analytical ultracentrifugation in 6 M guanidine of the fully reduced and alkylated half-molecule indicated that this myeloma protein had a heavy chain of a smaller molecular weight (approximately 45,000) than that of normal gamma chains, Except for this apparent deletion, the heavy chain resembled gamma1 chains. The amino acid composition of the peptides containing the half-cysteine residues forming the interchain disulfide bonds, the glycopeptide of the Fc fragment and the COOH-terminal structure were similar if not identical with the analogous structures of gamma1 chains. No Fc fragment could be prepared because the Fc portion of the heavy chain of the myeloma protein was extremely susceptible to degradation with papain. After mild reduction and alkylation, the 7S myeloma protein dissociated into half-molecules, indicating a lack of noncovalent interactions in the Fc fragment that are present in all classes of human immunoglogulins and are responsible for the formation ofFc dimers. The half-molecule was antigenically deficient in the Fc fragment. It failed to precipitate with anti-Fc fragment antisera in double gel diffusion tests and inhibited a Fc-anti-Fc fragment binding reaction weakly and incompletely. The half-molecule and the 7S protein had the same genetic markers on the first and second homology region of the gamma chain. The half-molecule lacked, however, the corresponding markers on the third homology region, These findings suggest that this myeloma protein had a deletion in the gamma chain which was probably located in third homology region and was likely the structural abnormality responsible for the lack of noncovalent interaction in the Fc fragment and absence of most of the antigenic determinants characteristic of gamma chains.
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PMID:Human myeloma IgG half-molecules. Structural and antigenic analyses,. 5 83

Adenoid cystic carcinoma cells cultivated in monolayer and sponge matrix culture, or implanted on the chorioallantoic membrane (CAM) of embryonated eggs, were observed morphologically, and the glycosaminoglycan components in the tumor tissue were analyzed. This tumor tissue contained a large amount of glycosaminoglycans, composed of chondroitin 4- and 6-sulfate, heparan sulfate, hyaluronic acid, and a small amount of dermatan sulfate. In monolayer culture spindle cells proliferated vigorously as multilayer, and secreated mucinous material. In sponge matrix culture, the proliferating cells became embedded in the material produced by the cells themselves. A trace of fine fibers stained with orceine was observed in the intercellular material in culture. Histologic sections of the implants grown on CAM showed that the tumor cells arranged in various structures produced a large amount of mucinous material that spread into the stromal area without any contribution from the mesenchymal element. The morphologic and biologic characteristics of these tumor cells are quite similar to those of pleomorphic adenoma.
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PMID:Morphologic and biologic characteristics of adenoid cystic carcinoma cells of the salivary gland. 6 17

Partial biochemical characterization of several neural tissue specific antigens isolated from a murine glioblastoma cell line was accomplished by means of radioiodination of intact cells followed by immunoprecipitation of the cell lysate with a rabbit serum specific for neural tissue antigens. Polyacrylamide gel electrophoresis of the immunoprecipitate in sodium dodecyl sulfate resolved the labeled antigens into several major components: two proteins (or glycoproteins) having apparent m.w.'s of 84,000 and 120,000 and lipid associated components which may be heterogeneous. The protein and lipid associated components apparently possess independent antigenicity because after chloroformmethanol extraction the protein components can be immunoprecipitated from the aqueous phase and the lipid associated component can be immunoprecipitated from the organic phase. Despite their independent antigenicity it is not known whether the components may be noncovalently associated on the cell surface. Although some of these antigens can be isolated from brain or glioma cells (a related tumor), non can be demonstrated in lymphoid tissues or C1300 neuroblastoma cells using identical methods. Therefore, these studies confirm our previous findings concerning the specificity of the anti-NS-2 antiserum by using cytotoxicity tests.
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PMID:Partial characterization of nervous system-specific cell surface antigen(s) NS-2. 6 27

Twenty-six patients with superficial Stage O or A transitional cell carcinoma of the urinary bladder, whose lesions were not amenable to transurethral resection, received bleomycin sulfate intravesically at weekly intervals for eight treatments. Five different drug regimens were tried, and the optimal concentration appeared to be 60 units dissolved in 30 cc. of sterile water. Serum determinations failed to reveal any significant absorption. There was a 27% complete response rate in patients with small tumor burdens. An additional 9% had partial responses which allowed the tumors to be readily managed transurethrally. However, no patients with extensive superficial tumor showed complete response to therapy. Although belomycin used intravesically is active against transitional cell carcinoma, the current cost of the drug precludes its routine use and restricts it to situations in which other agents are contraindicated.
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PMID:Treatment of multiple superficial tumors of bladder with intravesical bleomycin. 6 19

The synthesis and identity of the tumor and U antigens of simian virus 40 (SV 40) have been examined during productive infection in monkey cells, abortive infection in mouse cells, and in SV40-transformed mouse cells by using sodium dodecyl sulfate/polyacrylamide slab gel electrophoresis to analyze [35S]methionine-labeled radioimmune precipitates. The following observations were made: (i) the tumor and U antigenic sites are on the same 94,000, 89,000, and 84,000 molecular weight species detected during productive infection; a 94,000 species made during abortive infection; and a 94,000 species found in transformed cells. (ii) The 94,000 species is relatively unstable compared to the relatively stable 89,000 and 84,000 species produced during productive infection. (iii) The stable 89,000 and 84,000 molecular weight species are differentially extracted from productively infected cells, which suggests an intracellular compartmentation and/or different affinities of these species for cellular substrates. (iv) The 94,000 species synthesized during abortive infection is more stable than the comparable 94,000 species synthesized in transformed cells. (v) Three tsA group mutants overproduce several unstable species of tumor antigen at restrictive temperature.
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PMID:Identification of simian virus 40 tumor and U antigens. 6 77

Three human lung tumor-associated antigens (TAA's) have been identified in soluble and membrane-solubilized extracts of human squamous cell lung carcinoma with the use of antisera raised in rabbits. The antigens were identified and partially characterized by means of an agarose adsorption technique. These antigens, termed lung TAA's 1,2, and 3, are all soluble in 50% ammonium sulfate, are antigenically distinct, and do not cross-react with carcinoembryonic antigen or alpha-fetoprotein. Lung TAA's 1 and 2 are oncofetal antigens demonstrable in soluble extracts from 24-week-old but not from 26-week-old fetal lungs. Rabbit antibodies to these lung TAA's were not adsorbed by types A, B, and O human red blood cells, serum proteins as well as soluble or insoluble lung preparations. Of several commercial antisera to human proteins, none cross-reacted with lung TTA 1, but anti-human liver ferritin cross-reacted with lung TAA 2, and anti-human lactoferrin cross-reacted with lung TAA 3. Lung TAA 1 was partially adsorbed and cross-reacted with certain normal serum or plasma preparations used and appears to be a normal serum protein in Cohn Fraction IV-4. Lung TAA 2 and 3 appear only in lung tumor-soluble extracts, whereas the lung TAA 1 was demonstrable in soluble extracts of breast, colon, cervical and head and neck carcinoma. All may be tumor markers of value in immunodiagnosis.
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PMID:Isolation and identification of human lung tumor-associated antigens. 6 79

The feasibility of using protein A-containing Staphylococcus aureus to measure antibodies in sera from several mammalian species was studied. A variety of unrelated radiolabeled antigens were tested, including components of bovine serum, DNA, and bacterial and tumor-associated extracts. The use of S. aureus was found to be a reliable way to detect and measure the primary interactions between many of the antigens and antibodies tested. Results were equivalent under many circumstances to those obtained with the ammonium sulfate and heterologous anti-immunoglobulin methoods. However, some of the limitations noted were that certain antigens bound directly to S. aureus and that all classes of human immunoglobulins tested, in particular IgG3 and IgA1, were not precipitated by S. aureus. If these limitations are taken into consideration, the use of S. aureus can be of value in studying immunochemical reactions with other antigens.
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PMID:Precipitation of radiolabeled antigen-antibody complexes with protein A-containing Staphylococcus aureus. 6 69


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