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)

Previously, we have stablished that the fifth component of complement (C5) serves as an important source of mediators that have locomotory (chemotactic) activity for leukocytes and tumor cells. C5a, a fragment (Mr 11,200) derived from the NH2-terminal portion of the alpha chain of C5, is the major chemotactic peptide for leukocytes. The present studies demonstrate that cleavage of C5a with trypsin generates a derivative peptide that is chemotactic for tumor cells (Walker carcinosarcoma). This fragment has an estimated Mr of 6000 as assessed by gel filtration and does not require the COOH-terminal arginine of C5a, because equivalent amounts of chemotactic activity for tumor cells can be generated from des-Arg-C5a by digestion with trypsin. The C5a-derived chemotactic peptide for tumor cells demonstrates peak activity at approximately 1 pM. These studies emphasize the key role of the C5a region of the C5 molecule in the generation of peptides that affect locomotory responses of cells.
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PMID:Chemotactic factor for tumor cells derived from the C5a fragment of complement component C5. 28 38

Karyotype analyses were conducted on spontaneous mammary tumors of 11 GR, 2 C3H, and 2 noninbred Swiss mice with the use of trypsin-Giemsa banding procedures. All tumors manifested trisomy of chromosome No 13 in most cells, and all except 1 tumor had cells with a model chromosome number of 40.
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PMID:Trisomy of chromosome No 13 in spontaneous mammary tumors of GR, C3H, and noninbred Swiss mice. 28 29

When cultured in-vitro, originating from different breast cancer patients, tumor cells, identified histologically as carcinoma cells, varied in their proliferation patterns and cell morphology. If exposed for brief periods to vibrio cholera neuraminidaes (VCN), the amount of sialic acid released from the cells varied from one culture to another and increased with higher enzyme concentrations. If exposed to trypsin, the amount of released proteins varied also from one culture to another. Significant difference was observed between the effect of VCN or collagenase on normal and neoplastic cell cultures. Whether human or murine cell cultures, the cell-free media harvested from cultures of neoplastic cells containing high concentrations of collagenolytic-caseinolytic-fibrinolytic and esterolytic activities. Two effects of concanavalin A (Con A) have been distinguished on thymidine incorporation, the first is a decrease in the maximal thymidine uptake, whereas the second is a shift to the maximum thymidine uptake to higher Con A concentrations. At low concentrations, alpha-1-antitrypsin (AAT) had no effect, but at high concentrations it inhibited 3H-thymidine uptake. At low concentrations human profibrinolysin inhibited and at higher concentration sit enhanced uptake of the labeled precursor. Therefore, the collagen olytic caseinolytic-fibrinolytic enzyme is a pacemaker for proliferation of human mammary carcinoma cells.
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PMID:Human mammary carcinoma cells. The enzyme pacemaker profibrinolysin. 31 26

Regional (popliteal) lymph node cells (RLNC) from A/Jax mice, inoculated in each hind foot with isogeneic Sarcoma 1 tumor cells, demonstrated cytotoxicity in vitro at Day 14 of tumor growth but lost this ability by Day 21. These noncytotoxic RLNC were capable of suppressing activity of other cytotoxic lymphoid cells, but after incubation for 24 hr in vitro their cytotoxicity was restored and their suppressive activity was abrogated. RLNC responsible for cytotoxicity were removed by treatment with anti-theta serum plus complement. The suppressive effect of RLNC was found to be mediated by a soluble "blocking" factor which was released into the culture medium after 24 hr incubation. The factor was not detected in culture media from RLNC pretreated with anti-theta serum plus complement prior to incubation. Absorption of RLNC culture supernatants with tumor-bearer spleen cells, but not with normal spleen cells, completely removed the blocking factor, while absorption by Sarcoma 1 cells significantly reduced blocking activity. The factor was trypsin sensitive, was retained on an Amicon XM100 filter, and did not demonstrate the presence of antibody to Sarcoma 1 in a radioimmunoassay. Although the exact nature of the factor has not been established, it appears to be a receptor antigen complex from T-cells of tumor-bearing animals.
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PMID:Immunological activity of regional lymph nodes in tumor-bearing mice. 31 91

We have quantitated the transformation-sensitive, cell surface LETS glycoprotein on many untransformed cell types. By SDS-polyacrylamide gel electrophoresis, this trypsin-sensitive iodinatable glycoprotein comprises 1-3% of total cellular protein of the seven early passage cell types tested. In contrast, it constitutes less than 0.15% of the protein in four of six continuous cell lines. This decrease is reflected in alterations both in [14C]glucosamine labeling and in the immunofluorescent staining of early passage vs. these four permanent cell lines. These results help to clarify previous experiments in which CSP, a purified LETS protein, partially restored a fibroblastic phenotype to cells transformed by tumor viruses. These findings also indicate that a major decrease in this cell surface glycoprotein can occur in the establishment of a continuous cell line without resulting in cellular transformation.
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PMID:Quantitation of a transformation-sensitive, adhesive cell surface glycoprotein. Decrease of several untransformed permanent cell lines. 32 19

Direct comparison of the effector cells mediating natural killer (NK) activity against mouse tumor cells and antibody-dependent cell-mediated cytotoxicity (ADCC) against mouse tumor target cells coated with alloantisera indicated that NK cells and K-cells (effector cells mediating ADCC) may belong to the same subpopulation of lymphocytes, but they have a different mechanism of killing. Effector cells mediating NK activity and ADCC were nonadherent, nonphagocytic Fc receptor-bearing cells that sediment at 3.5-4.5 mm/hour. Treatment with anti-Thy 1.2 serum in the absence of complement resulted in an increase of NK activity, whereas this treatment caused a substantial loss in ADCC. Both NK activity and ADCC were equally sensitive to the in vivo or in vitro effects of X-irridiation. In vivo inoculations of high doses of hydrocortisone resulted in a reduction of NK activity, but ADCC was not affected. NK cells were trypsin-sensitive, with a profound decrease in the cytolytic activity being observed in a 4-hour 51Cr release assay. The activity, however, could be recovered after overnight incubation at 37 degrees C. Trypsin treatment did not inhibit ADCC as measured by the 18-hour assay.
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PMID:Correlation between natural and antibody-dependent cell-mediated cytotoxicity against tumor targets in the mouse. II. Characterization of the effector cells. 38 12

Plasminogen, the inactive precursor of plasmin, a general trypsin-like proteinase, is present at high concentration in blood and in body fluids. Most cells can recruit this proteolytic potential by secreting plasminogen activator (PA) to generate localized proteolysis in the surrounding microenvironment. PA and plasmin are serine enzymes whose pH optima match extracellular pH; further, in view of the large amount of circulating proenzyme and the broad substrate range of plasmin, the possibility that this proteolytic system can initiate a variety of proteolytic reactions or sequences should be kept in mind. PA production is precisely regulated by hormones, temporal programming, or both; and enzyme synthesis is correlated with some physiological and pathological processes requiring proteolysis. Thus PA production is coordinately regulated with ovulation, trophoblast implantation, spermatogenesis, polypeptide hormone synthesis, and some developmental phenomena; and with inflammation, tumour promotion, and neoplasia. Tissue remodelling and cell migration are common to many of these processes. Macrophage (monocyte) and polymorphonuclear leucocyte PA production is modulated by many biologically active substances. Enzyme synthesis is induced and stimulated by stimuli that recruit these cells to sites of inflammation, and it is repressed by anti-inflammatory agents, notably by glucocorticoids.
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PMID:Neutral proteinases of leucocytes and the inflammatory process. 39 97

The size of androgen receptors from rat ventral and dorsal prostate, dorsal prostate (Dunning) tumor, testis, epididymis, and seminal vesicle was determined using Sephadex G-200 chromatogrpahy and sucrose gradient centrifugation. The protease inhibitor diisopropyl fluorophosphate (DFP) was used to minimize receptor breakdown. An 8-9 S, 85 to 106 A receptor (Mr = 280,000 to 365,000; f/fo = 1.9 to 2.4) observed in unfractionated cytosol prepared in low ionic strength buffer with or without DFP is in equilibrium with a 4.5-5 S, 58 A form (Mr = 117,000; f/fo = 1.8) observed at salt concentrations greater than 0.1 M KCl. Receptor partially purified using (NH4)2SO4 or phosphocellulose chromatography in the absence of DFP was present as smaller fragments of 3.6 S, 37 A and 3.0 S, 23 A. Similar fragments could be generated from the 4.5 S or 8 S receptor by mild trypsin treatment. In addition, ventral prostate contains a DFP-insensitive enzyme which specifically converts the 4.5 S, 58 A receptor to the 3.6 S 37 A fragment. The DFP-insensitive enzyme is partially inhibited by rabbit bile and appears similar to the enzyme seminin, a secretory protein of human prostate. Androgen receptor isolated in the presence of DFP from nuclei labeled in vivo is predominantly 4.5 S, 58 A, with smaller forms (37 and 23 A) appearing in the absence of DFP. The 4.5 S, 58 A nuclear receptors were also in equilibrium with a large 8 S form. Receptor breakdown by DFP-insensitive and sensitive proteases appears to be an in vitro phenomenon. Furthermore, the size of the androgen receptor is not significantly changed during receptor migration from cytoplasm to nucleus.
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PMID:Effects of proteases and protease inhibitors on the 4.5 S and 8 S androgen receptor. 44 15

The number of tumor-infiltrating macrophages was estimated in 43 patients with skin cancer, including 18 cases of squamous cell and 25 cases of basal cell carcinoma. Macrophages were identified in cell cultures by 2 assays, namely phagocytosis and resistance to detachment by trypsin. The average percentage of adherent cells for the 2 groups of skin tumors was 4.5 +/- 2.6 and 10.2 +/- 5.2, respectively, and the difference was statistically significant. Follow-up studies after surgical excision of the primary neoplasm showed a relatively low macrophage content in 2 of the 4 cases in which local recurrences occurred. Preliminary functional studies suggested that soluble factors may be released by neoplastic cells, accounting for the inhibitory effect of tumor cell supernatants on macrophage chemotaxis in vitro.
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PMID:Macrophages in skin cancer: quantitative and functional studies. 46 81

Tumour extracts were obtained from rat Walker 256 carcinoma and examined for the presence of tumour angiogenesis factor (TAF) in vivo before being used in tissue culture experiments. Capillary endothelial cells derived from cow brain white matter were used to study the effects of TAF-containing tumour extracts on cell proliferation in vitro. The cells were grown on two types of substrata: (1) plastic tissue culture dishes and (2) hydrated gels made of rat tail tendon type I collagen. Human platelets or platelet-released factors were introduced into the system because of the many inter-relationships known to exist between platelets, collagen and endothelial cells. If trypsin was used during the preparation of TAT, the resulting batches stimulated endothelial cell proliferation only when the cells were growing on a collagen substratum and either platelets or platelet-released factors were present in the growth medium. If incubation with trypsin was omitted from the TAF extraction procedure, the resulting batches stimulated cell growth both on plastic and on collagen. A synergistic interaction also occurred between these TAF-containing tumour extracts and platelet-released factors. This effect was always more marked when the cells were growing on collagen than when on plastic. These data suggest that the nature of the substratum affects the response of the endothelial cells to TAF and to platelet-released factors.
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PMID:Importance of a collagen substratum for stimulation of capillary endothelial cell proliferation by tumour angiogenesis factor. 48 64


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