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)

The correlation between the content of individual glycosaminoglycans and the histological patterns are studied on breast tumor tissues. The myxomatous stroma of intracanalicular fibroadenoma contained a large amount of glycosaminoglycans, which were mainly hyaluronic acid. The chondroitin 4- and 6-sulfate level was also high. As the supporting stroma of this tumor became denser and more fibrous, the level of hyaluronic acid content was reduced. In the case of pericanalicular fibroadenoma, glycosaminoglycans were small in amount and the levels of hyaluronic acid and chondroitin sulfate were low, but the ratio of dermatan sulfate content was higher. In the case of gynecomastia, the conent was almost the same as that of pericanalicular fibroadenoma. Scirrhous carcinoma tissues contained a relatively large amount of hyaluronic acid and chondroitin sulfate. No remarkable differences in heparan sulfate content were observed in any one of the breast tumors tested. Dermatan sulfate-chondroitin sulfate copolymers were detected in all the tumors. The presence of dermatan sulfate seemed to have an intimate relation with the fibrogenesis in the interstitial stromal element of the tumor tissues.
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PMID:Variation in glycosaminoglycan components of breast tumors. 17 97

Pyrimidine nucleoside monophosphate kinase [deoxycytidine monophosphate:adenosine triphosphate (dCMP:ATP) phosphotransferase. EC 2.7.4.14] has been purified from rat Novikoff ascites hepatoma and rat liver, each to a single major band appearing on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Differences exist in regard to efficiency and regulation of enzymatic activities. The Km values of the tumor kinase for cytidine monophosphate (CMP) (0.0053 +/- 0.0008 MM) and dCMP (0.715 +/- 0.068 MM) are approximately one-fourth the Km values of the rat liver kinase, for CMP (0.030 +/- 0.007 MM) and dCMP (2.77 +/- 0.39 MM). The tumor dCMP kinase exhibits a lower Km for ATP (0.134 +/- 0.008 MM) than the rat liver kinase (0.68 +/- 0.09 mM). Moreover, the dCMP:CMP kinase activity ratio for the tumor enzyme is 1.12, while that for the rat liver enzyme is 0.45. The uridine monophosphate:CMP kinase activity ratio for the tumor enzyme is 1.93, while that for the rat liver enzyme is 2.68. Lower concentrations of dithiothreitol are required for 50% reactivation of the tumor dCMP kinase (1.00 mM) and CMP kinase (0.10 mM) than rat liver dCMP kinase (2.20 mM) and CMP kinase (0.57 mM). Thus, the kinase from Novikoff hepatoma exhibits properties of increased efficiency and relaxed regulation of activity which render it more suitable for a tumor, in which active DNA synthesis is ongoing.
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PMID:Differences between pyrimidine nucleoside monophosphate kinase from rat Novikoff ascites hepatoma and rat liver. 17 2

Mouse pituitary tumor cells (AtT-20/D-16v) were incubated in medium containing [3H] glucosamine or [3H] mannose. By analyzing immunoprecipitates of cell extracts and culture medium it was shown that [3H] glucosamine and [3H] mannose were incorporated into all three high molecular weight forms of ACTH; label was not incorporated into Mr=4,500 ACTH (which is thought to be similar to the 39 amino acid polypeptide form of ACTH, alpha(1-39)). Based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis the apparent molecular weights of these glycoprotein forms of ACTH were 31,000, 23,000, and 13,000. Gel filtration in 6 M guanidine HCl indicated that the molecular weights of these forms of ACTH were substantially lower; sodium dodecyl sulfate-polyacrylamide gel electrophoresis has often been found to overestimate the molecular weight of glycoproteins. A significant fraction of the high molecular weight ACTH in tumor cell extracts binds to columns of concanavalin A-agarose and can be eluted with 0.2 M alpha-methyl-D-mannopyranoside; porcine alpha(1-39) does not bind to concanavalin A-agarose. High molecular weight glycoprotein ACTH can be detected in extracts of mouse and bovine pituitary by using concavalin A affinity chromatography.
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PMID:High molecular weight forms of adrenocorticotropic hormone are glycoproteins. 18 16

Thirty-three patients with malignant glioma were randomly divided into two groups after extensive tumor resection. Those in group A received, every five to eight weeks, a course of chemotherapy consisting of intravenously administered carmustine, 80 mg/sq m/day for three days, and vincristine sulfate, 1.4mg/sq m on days 1 and 8. Patients in group B were treated identically and received radiation therapy (RT) as well, 4,500 rads whole brain plus 1,500 rads to the side of the tumor. The median survival time of group A was 30 weeks, while that of group B was 44.5 weeks, but the overall survival curves were not significantly different. The median survival times exceeded the 17 weeks reported elsewhere in comparable patients not receiving postoperative therapy. Estimates of the quality of survival suggested (1) the two groups were not comparable following randomization, possibly influencing the results; and (2) postoperative radiation and chemotherapy do not increase morbidity and offer a longer period than other treatments during which patients' conditions remain stable or improve.
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PMID:Treatment of malignant glioma. A controlled study of chemotherapy and irradiation. 18 Sep 38

The synthesis and release of feline leukemia virus p30 was studied using a permanently infected feline thymus tumor cell line. Disrupted cells were divided into two subcellular fractions, a cytoplasmic extract (CE) representing cellular material soluble in 0.5% NP-40 and a particulate fraction (PF) insoluble in 0.5% NP-40 but soluble in 0.2% deoxycholate and 0.5% NP-40. Intracellular feline leukemia virus p30 was isolated from infected cells by immune precipitation with antiserum to p30 and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the precipitated proteins. Cells labeled for 3 h with [35S]methionine contained equal amounts of p30 in both the CE and the PF. p30 synthesis was estimated to be 0.8% of the total host cell protein synthesis. Immune precipitates from cell pulse labeled for 2.5 min contained a labeled 60,000-dalton polypeptide (Pp60) in the PF and a polypeptide in the CE that comigrated with feline leukemia virus p30 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When cells were chased after a pulse label, there was a rapid loss of Pp60 in the PF and an accumulation of p30 in the CE within 30 min followed by distribution of p30 in both the PF and the CE. Estimation of intracellular and extracellular p30 levels during a 0.5- to 24-h chase period suggested that most of the newly synthesized p30 was incorporated into extracellular virus. Typtic peptide analysis of labeled Pp60 and p30 demonstrated the presence of 13 of 15 p30 peptides within the Pp60 molecule. The tryptic peptide analysis in concert with the pulse-chase labeling data provides strong evidence that Pp60 is a precursor of p30.
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PMID:Analysis of intracellular feline leukemia virus proteins. I. Identification of a 60,000-dalton precursor of feline leukemia virus p30. 18 22

In order to understand the mechanism by which cyclic 3':5'-adenosine monophosphate (cAMP) regulates insulin secretion, cAMP-dependent protein phosphorylation was studied in a transplantable hamster islet cell tumor. Single cell suspensions prepared by enzymatic digestion of the tumors released insulin into the incubation media. Glucagon (3 nM to 3 muM) stimulated cellular cAMP accumulation and insulin release in a dose-dependent manner and these effects were enhanced by 1 mM theophylline. 8-Bromoadenosine 3':5'-monophosphate (8Br-cAMP) (1 mM) increased insulin release. Somatostatin (10 mug/ml) inhibited basal and glucagon or 8Br-cAMP-stimulated insulin release without significantly lowering cellular cAMP in glucagon-stimulated cells. For analysis of phosphoproteins, cells were incubated with carrier-free 32Pi following which lysates were prepared and analyzed by sodium dodecyl sulfate slab gel electrophoresis and autoradiography. Of the numerous 32P-labeled protein bands found, only one (P1, Mr = 28,000) displayed a significant increase in 32P incorporation when cells were incubated under conditions that raise the concentration of cellular cAMP. Somatostatin did not affect 32P incorporation into P1 or any other protein band. When cells were incubated with glucagon, an increase in cellular cAMP was evident after 1 min, enhanced 32P incorporation into P1 after 1 to 5 min, and stimulation of insulin release after 5 to 10 min. Analysis of subcellular fractions led to the designation of P1 as a 40 S ribosomal protein. Two-dimensional electrophoresis of 32P-labeled basic ribosomal proteins showed two labeled proteins, P1 and P2, both of which were localized to the 40 S ribosomal subunit. Only phosphorylation of P1 was stimulated by cAMP. The cAMP-dependent ribosomal phosphoprotein, P1, may be identical with a ribosomal phosphoprotein demonstrated in a variety of tissues and species. Its physiological role remains to be established.
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PMID:Cyclic adenosine 3':5'-monophosphate-mediated insulin secretion and ribosomal protein phosphorylation in a hamster islet cell tumor. 18 14

A solubilization technique employing 0.5% Triton X-100 was developed to obtain both SV40 virus (SV40)-induced tumor-specific surface antigen(s) (TSSA) from SV40-transformed mouse cells, as determined by a serum-mediated microcytolytic assay, and tumor-specific transplantation antigen(s) (TSTA), as determined by in invivo experiments. High yields (approximately 50%) of TSSA were obtained in whole-cell extracts and also after ammonium sulfate fractionation. Additional fractionation of a 30-50% ammonium sulfate fraction by gel exclusion chromatography on Sephadex G-150 resulted in two pooled fractions which contained TSSA activity. The first eluted close to the void volume, and the second in the 45,000 molecular weight region. The various TSSA active fractions were also active in vivo TSTA tests. Detergent solubilization provides a suitable technique to recover the SV40-induced antigens in good yield, and apparently in intact form.
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PMID:Detergent solubilization and partial purification of tumor specific surface and transplantation antigens from SV40-virus-transformed mouse cells. 19 Jan 77

Surface antigens were extracted in soluble and active form with 3 M KCL from polyoma virus-transformed and embryonic hamster cells. These were tumor-specific transplantation antigens (TSTA), shown by tumor rejection, and a surface (S) antigen, demonstrated by the inhibition of surface fluorescence on living polyoma virus-transformed cells. The extracts were fractionated by salting out with ammonium sulfate. In tumor cell extracts, all TSTA activity and a part of S antigen activity were found in the fraction precipitated with 60% saturation in (NH/)2SO4. Another part of S antigen activity was found in the fraction precipitating at 80% saturation in tumor cell extracts. The precipitate at 60% saturation of embryonic cell extracts also had a part of S antigen activity. Receptor site activity for concanavalin A was also retained after solubilization and was confined to the 40% saturation (NH4)2SO4 precipitate in the case of tumor and embryonic cell extracts.
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PMID:Isolation of polyoma virus-induced surface antigens in hamster cells: potassium chloride solubilization and differential precipitation. 19 Apr 15

The inhibitory effect of sulfated polysaccharides on blood-borne metastasis was examined. As a model of blood-borne metastasis, the ascitic form of hepatoma AH-109A tumor was injected intravenously into Donryu strain rats. Examination of the pulmonary metastatic nodules developed 2 weeks later showed inhibitory effect of the five sulfated polysaccharides tested. Xylan sulfate was the most inhibitory, and exerted its inhibitory effect when the tumor cells were in the pulmonary capillary beds. However, fromthe rapid disappearance of radioactivity from the lungs after injection of 125IUDR-labeled AH-109A cells, tumor cells seemed to be retained in the lungs for only a very short time. Measurement of the anticoagulative and fibrinolytic activities of three sulfated polysaccharides showed that the inhibitory effect of these compounds on blood-borne metastasis was proportional to their anticoagulative and fibrinolytic activities, xylan sulfate showing the highest activities. These results suggest that sulfated polyaccharides may inhibit blood-borne pulmonary metastasis by inhibiting the lodging of tumor cells in the pulmonary capillary beds.
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PMID:Effect of sulfated polysaccharides on blood-borne pulmonary metastasis in rats. 19 22

A protein kinase, designed KII, has been purified 5000-fold from Novikoff ascites tumor cells. The purification procedure also allows for the purification of a second major protein kinase, designated KI, as well as RNA polymerase I and II. Purified KII has a sedimentation constant of 7.6 S and a Stokes radius of 39 A, suggesting a molecular weight of about 122000. Polyacrylamide gel electrophoresis of the enzyme in the presence of sodium dodecyl sulfate suggests the enzyme is composed of subunits of molecular weights 44 000, 40 000, and 26 000 present in a molar ratio of 1:1:2. Incubation of the enzyme alone in the presence of [gamma-32P]ATP results in the phosphorylation of the 26 000-dalton subunit. Protein kinase II actively phosphorylates phosvitin, casein, and nonhistone chromosomal proteins but does not phosphorylate basic proteins such as histones or protamine to an appreciable extent. Km values of 3.6 micron for ATP and 6.5 micronM for GTP were determined in the presence of 4mM Mg2+. The enzyme is neither stimulated by cyclic adenosine 3',5'-monophosphate or cyclic guanosine 3', 5'-monophosphate nor inhibited by the regulatory subunit of rabbit muscle protein kinase. Its activity is stimulated by KCl at concentrations below 0.2 M and inhibited by higher concentrations.
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PMID:Purification and characterization of Novikoff ascites tumor protein kinase. 19 79


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