Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1261473 (sarcoma)
 25,952 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

DNA distribution in biopsies and cell cultures of human gliomas was examined by flow-fluorescence-cytometry using ethidium bromide staining. Glioblastomas (n = 25) showed "polyploid", "marked tetraploid", or "hypertetraploid" aneuploid karyograms, comparable to subtypes previously proposed by Japanese authors. "Diploid-hyperdiploid" DNA patterns were manifest in 3 cases plus 1 sarcoma--glioblastoma, containing abundant rapidly growing mesenchymal cells. Most tumors showed S-phase increment. "Near-diploid" patterns could be a result of aggregated cells, and small 4 C peaks could be due to non-representative specimens (3 cases). During cultivation, the DNA distribution usually remained stable, but maxima occasionally shifted. Oligodendrogliomas (n = 11) and astrocytomas (n = 9) of low-grade showed low 4 c peaks. High-grade gliomas, however, showed abnormal DNA patterns. Thus, one case of an oligodendroglioma--I developed an abnormal "marked tetraploid" glioblastoma after a 3-year interval presenting its malignant transformation. DNA distribution can obviously vary during tumor evolution. However, it may well support the assessment of grading and more closely define the prognosis in gliomas.
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PMID:Flow-cytophotometry of nuclear DNA in biopsies of 45 human gliomas and after primary culture in vitro. 375 47

Replicative DNA synthesis in permeable mouse sarcoma cells was more sensitive to ethidium bromide (EtBr) than bleomycin-induced unscheduled DNA synthesis (UDS). A similar difference in sensitivity to EtBr was observed between DNA polymerases alpha and beta. The difference in sensitivity to EtBr of replicative DNA synthesis and UDS in the present system seems to reflect mainly the sensitivity difference between DNA polymerases alpha and beta.
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PMID:Differential sensitivity to ethidium bromide of replicative DNA synthesis and bleomycin-induced unscheduled DNA synthesis in permeable mouse sarcoma cells. 620 93

In vitro translation of virion RNA of Moloney murine sarcoma virus (MSV) strain 124 yielded major products having molecular weights of 63,000 (63K), 43K, 40K, 31K, and 24K daltons. A molecularly cloned subgenomic fragment of Moloney MSV comprised of the cellular insertion (src) region was utilized in hybridization arrest translation as a means of identifying products of the MSV src gene. MSV src DNA specifically inhibited synthesis of the 43K, 40K, 31K, and 24K proteins, implying that each of these proteins was coded within the MSV src gene. The MSV src-specific nature of this family of proteins was further confirmed by partial purification of MSV src-containing RNAs from MSV non-producer cells. In vitro translation of enriched cellular RNAs yielded products with molecular weights identical to those of the 43K family of proteins synthesized from virion RNA. Nucleotide sequence analysis of the MSV transforming region has revealed a long open reading frame which includes five methionine codons (Reddy et al., Proc. Natl. Acad. Sci. U.S.A. 77:5234-5238, 1980). The molecular weights of the four largest proteins that could be synthesized within this open reading frame corresponded closely to the molecular weights of the 43K family of proteins. Partial cyanogen bromide cleavage of each of the three largest proteins resulted in an uncleaved fragment having a molecular weight equal to that of the smallest (24K) protein. These findings provide direct biochemical evidence that the 43K, 40K, 31K, and 24K proteins are related in their carboxy-terminal regions, as well as information concerning the MSV src gene coding sequences from which each protein originates:
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PMID:Translational products of Moloney murine sarcoma virus RNA: identification of proteins encoded by the murine sarcoma virus src gene. 626 37

In HTG2 hamster cells infected with the replication-defective Gazdar murine sarcoma virus only immature virus particles are formed, with the uncleaved gag precursor Pr65 as the only major protein in the virion. We have investigated the structure of these particles by using in situ cross-linking followed by chemical and enzymatic cleavages of Pr65 to localize sites of lipid-protein and protein-protein interactions. Lipid-protein cross-links were localized within a 10-kDa fragment in the p15 region of Pr65. Homotypic protein-protein cross-links between Pr65 units were localized within the p15 regions and also within the p10 regions of Pr65. Similar data for processed gag proteins in Rauscher murine leukemia virus, a prototype of a mature C-type virus, suggest that these interactions of the gag precursor are not altered during maturation. To identify the sites of cross-linking within Pr65, we have developed a two-dimensional peptide mapping technique that is based on nearest neighbor analysis of fragments released by cyanogen bromide treatment of partial cleavage products in gel slices. In conjunction with cross-linking, the peptide mapping technique is a powerful means for localizing specific interactions on a polypeptide backbone.
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PMID:Localization of lipid-protein and protein-protein interactions within the murine retrovirus gag precursor by a novel peptide-mapping technique. 630 37

A double-stranded RNA-specific nuclease (ds RNase) has been isolated and partially purified from human placenta by DEAE-cellulose and DNA-cellulose column chromatography. Denatured DNA-cellulose retained most of the single-stranded RNA-specific nuclease (ss RNase) activity, whereas the ds RNase came out in the void volume. N-ethylmaleimide at a concentration of 5 mM, selectively inhibited ds RNase activity by 60% under the conditions in which the ss RNase activity was inhibited to an extent of 7%. The ds RNase was specifically inhibited by Penicillium chrysogenum viral ds RNA and by ethidium bromide. The partially purified ds RNase showed requirements for Mg+ whereas Mn2+ and NH4+ ions were inhibitory. The DEAE-enzyme cleaved 32P-labelled 45S ribosomal precursor RNAs from Yoshida ascites sarcoma cells into species that had similar electrophoretic mobilities as the mature rRNAs.
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PMID:Partial purification and characterization of a double-stranded RNA-specific nuclease from human placenta. 663 20

The superhelical properties of chromosomal DNA from cells of a mouse sarcoma were investigated in neutral sucrose gradients containing ethidium bromide. Removal of negative supercoiling from the DNA of the sarcoma cells required a substantially higher dye concentration than was necessary in the case of DNA from cultured mouse fibroblasts. The calculated value of the mean superhelical density in malignant cells (sigma = -0.14) appears abnormally high compared with the value (sigma = -0.09) obtained for DNA of mouse fibroblasts. Chromosomal DNA from mouse sarcoma cells is therefore concluded to be highly deficient in helical turns.
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PMID:Extremely underwound chromosomal DNA in nucleoids of mouse sarcoma cells. 730 52

Type IV collagen from the EHS sarcoma, a basement membrane producing tumor, was characterized. Acid extracts of tumor grown in lathyritic animals contain proteins with two predominant collagen chains of apparent molecular weights of 160,000 and 140,000 daltons, designated alpha 1(IV) and alpha 2(IV). In addition, dimers and larger polymers formed by covalent crosslinking of the alpha 1(IV) and alpha 2 (IV) chains are also present. These two chains were found to be distinct from one another in amino acid composition and in the peptide patterns obtained following treatment with cyanogen bromide and S. aureus V8 protease. Precipitation of native collagen from acid solutions by the stepwise addition of NaCl yielded mixtures of the two chains with varying ratios suggesting that the two chains reside in different macromolecules.
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PMID:Type IV collagen contains two distinct chains in separate molecules. 734 19

Spontaneously transformed Chinese hamster lung cells with high levels of resistance (approximately 100-fold to 70,000-fold) to actinomycin D, daunorubicin, or vincristine exhibit morphology and growth patterns characteristic of normal cells in vitro and reduced tumorigenicity in vivo. These reverse transformed, multidrug-resistant cells amplify and highly overexpress one or more genes encoding P-glycoprotein. Similarly, hydrocarbon-induced mouse sarcoma cells selected with actinomycin D, vincristine, or ethidium bromide developed high levels of resistance associated with reduced drug accumulation and suppression of malignancy. To determine whether human tumor cells would undergo similar changes and whether reverse transformation reflected an altered state of differentiation, nine multidrug-resistant sublines were selected with four agents from human neuroblastoma cells with well defined pathways of differentiation. Those five with resistance levels above about 125-fold showed a reduced tumor frequency as compared to control cells. All resistant sublines showed altered differentiation. The changes in transformation phenotype appear to be intrinsic and not the result of altered immunogenicity. Two additional consequences of high level multidrug resistance have been observed: change in ganglioside composition in the Chinese hamster cells, manifested as a block in higher ganglioside biosynthesis and/or a relative increase in GM3, and increase in epidermal growth factor receptor in all three cell systems. A tentative hypothesis links ganglioside and growth factor receptor changes to the change in transformation phenotype. The basis of the reverse transformation phenomenon is not known, but the major alterations in expression of P-glycoprotein, gangliosides, and the epidermal growth factor receptor implicate, in some way, the plasma membrane.
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PMID:Reverse transformation of multidrug-resistant cells. 792 50

The chemosensitivity of 43 human sarcoma tissues, including 18 osteosarcomas, 16 leiomyosarcomas and 9 liposarcomas, was compared with that of 28 adenocarcinomas of the stomach, using the in vitro succinate dehydrogenase inhibition (SDI) test. These tissues were exposed for 3 days to each antitumor drug, including adriamycin (ADM), 5-fluorouracil (5-FU), mitomycin C (MMC), cisplatin (CDDP), aclacinomycin A (ACR) and carboquone (CQ), them the cell viability was estimated based on the succinate dehydrogenase (SD) activity, determined using [3-(4,5-dimethyl-2-thiazolyl) -2,5-diphenyl-2H tetrazolium bromide] (MTT). SD activity was significantly lower in the osteosarcoma as compared to that in the adenocarcinoma, for ADM, MMC, CDDP, ACR and CQ (p < 0.01), and was higher for ADM (p < 0.05) in cases of leiomyosarcoma and for CDDP (p < 0.01) and ACR (p < 0.05) in cases of liposarcoma. The sensitivity rate was higher in osteosarcoma than in adenocarcinoma for ADM, MMC and CDDP. These findings suggest that patients with osteosarcoma will probably show a fairly good response to antitumor drugs, and that when liposarcoma or leiomyosarcoma tumors show resistance to antitumor drugs, then resection at the time of initial exploration and combined modalities, including radiation and hyperthermia, should be considered.
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PMID:Antitumor chemosensitivity differs between clinical sarcoma and adenocarcinoma tissues. 816 44

The use of recombinant tumour necrosis factor (TNF) in the treatment of solid tumours has been limited by life threatening toxicity. In addition TNF may be a major mediator of the effect of endotoxins. Recent evidence suggested that a synergism between endotoxin (at the picogram level) and TNF may contribute to this toxicity. The use of the anti-endotoxin taurolidine may reduce TNF toxicity by interfering with this synergy. C57/BL6 mice (n = 140) received toxic doses (12 micrograms/mouse IV) of TNF. Four groups were studied. Group A received taurolidine 200 mg/kg IV 30 minutes before TNF, group B received TNF followed 30 minutes later by taurolidine 200 mg/kg IV, group C received an identical volume (0.5 ml) of normal saline 30 minutes prior to TNF, and group D taurolidine 200 mg/kg IP 45 minutes before TNF. The mortality rate of those mice receiving intravenous taurolidine 30 minutes prior to TNF was 8.8%. This was significantly less (P < 0.005) than the mortality rate achieved in groups B, C and D (33% vs 39.4% vs 50%). Further experiments employing an MTT (3-(4,5-dimethylthinzol-2-microliters)-2,5-diphenyl tetrazolinm bromide) assay showed that this was not due to direct interaction of taurolidine with TNF but is likely to be due to interference with the synergistic effects of endotoxin and TNF. It was also demonstrated in cotherapy studies in a murine model that taurolidine did not reduce the anti-tumour efficacy of TNF against the TNF sensitive mouse fibrosarcoma cell line Meth-A sarcoma.
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PMID:Taurolidine inhibits tumour necrosis factor (TNF) toxicity--new evidence of TNF and endotoxin synergy. 831 79


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