Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes of prekallikrein in the cases with DIC were investigated, i.e., DIC cases including disseminated metastasis of gastric cancer, acute promyelocytic leukemia and endotoxin shock. Therefore, the trigger substances for this paper were the pathologic cells of the leukemia, the cultured well differentiated adenocarcinoma cells and endotoxin. (1) The lysates of the pathologic cells of the leukemia and the cultured cells showed prekallikrein activation. Endotoxin showed prekallikrein activation via factor XII. (2) Serine proteases (factor Xa, thrombin, plasmin and trypsin) activated prekallikrein in the plasma and the purified prekallikrein. (3) Antithrombin III, aprotinin and FOY inhibited prekallikrein activation. Antithrombin III was promoted by heparin in its inhibitory effect.
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PMID:Changes of prekallikrein in the cases with disseminated intravascular coagulation syndrome. 16 Jan 91

Cytosols from 75 normal, 36 abnormal, and 5 decidual human endometrial tissue specimens were assayed for the presence of a high affinity, progesterone-specific binding protein. Thirty of the normal and 15 of the abnormal samples were found to contain a binder which would form a high-affinity complex with progesterone but not with cortisol, 17beta-estradiol, testosterone, or 5alpha-androstane-3-,17-dione. Incubation of cytosol with trypsin or incubation for 2 hours at 37 C abolished [3H]progesterone binding by these preparations, indicating the protein nature and heat-lability of the binder. The average equilibrium constant of dissociation, Kd, of the progesterone-binder complex was 4.0 X 10(-10)M in each phase of the menstrual cycle. The concentration of the binder varied over the cycle, however, with a significant peak at mid-cycle (P = .02). The average saturation values in femtomoles (fmoles)/mg protein ranged from 21 in the early proliferative phase to 64 in the late proliferative samples, dropping to 36 in early secretory and to 3 in the late secretory phase of the cycle. No progesterone-specific binding was detected in decidual samples. Saturable binding was demonstrable in 10 of 22 endometrial hyperplasias, 80-1840 fmoles/mg protein, with high affinity, Kd 3.3 X 10(-10)M. Two other hyperplasia samples bound progesterone, but with lower affinity. Two grade I adenocarcinomas, one grade III adenosquamous carcinoma, and one grade III adenocarcinoma contained the progesterone binder, but in 9 other cancers no detectable binder was present. A benigh adenocanthomyoma was found to contain a progesterone binder (18 fmoles/mg protein with a Kd of 2.5 X 10(-10)M).
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PMID:Progesterone binding by normal and abnormal human endometrium. 17 46

Normal and premalignant mouse mammary epithelial cells can be prepared in high yields by collagenase dissociation of minced glands followed by a brief, differential centrifugation to remove contaminating fibroblasts and fat cells. The major difficulties in preparing pure cultures in quantity are 1) incomplete dissociation of gland material, and 2) cell death during enzymatic digestion. These problems are eliminated by careful selection of collagenases for dissociation. Normal and premalignant mammary epithelial cells are morphologically indistinguishable from malignant mouse mammary epithelial cells in primary monolayer cultures. In addition, the growth rates and saturation densities achieved by normal mammary epithelial cells are indistinguishable from those of malignant mammary epithelial cells in primary culture. In both cases, a monolayer of cells is preserved with no evidence of focal overgrowth. Malignant adenocarcinoma mammary cells can however be distinguished from normal mammary epithelial cells by virtue of differences in their surface interactions with concanavalin A. A hemadsorption assay using Con-A-coated erythrocytes was the most sensitive indicator for these differences. In hemadsorption assays malignant mammary epithelial cells were half-maximally reactive with 2.5 mug/ml concanavalin A, while normal cells were completely unreactive even at concanavalin A concentrations five-times higher. Premalignant mammary epithelial cells were as reactive as malignant mammary epithelial cells in the hemadsorption assays. Hemadsorption of malignant cells was observed in primary and secondary cultures of epithelium as well as in cell lines. Malignant cells forming mammary adenocarcinomas were as highly reactive as malignant cells forming scirrhous carcinomas. Malignant cells not releasing mammary tumor virus (MuMTV) were as reactive as cells releasing that virus. Adsorption of concanavalin-A-coated erythrocytes to normal mammary epithelial cells could be induced by brief treatment of cell monolayers with hyaluronidase. Exposure of active sites was not affected with either trypsin or collagenase. Our results show that while the growth of malignant cells does not serve to distinguish them from normal cells in monolayer culture, surface changes do exist which can be identified by differences in concanavalin A reactivity. Since the earliest transformants identifiable in vivo (premalignant) have undergone conversion of the surface marker, concanavalin-A-mediated hemadsorption provides a sensitive measure for mammary epithelial cell transformants in vitro.
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PMID:Markers to distinguish normal and neoplastic mammary epithelial cells in vitro: comparison of saturation density, morphology and concanavalin A reactivity. 18 59

A new non-strain-specific ascites subline of the TA3 mammary adenocarcinoma TA3-MM, which arose in vivo from the strain-specific TA3-St subline during an acute respiratory illness of the syngeneic mouse strain A/HeHa hosts, possessed at its surface a glycoprotein not found on the parent TA3-St cell. This glycoprotein, termed TA3-MM epiglycanin, was characterized by a high molecular weight (500,000), by potent inhibition of hemagglutination by the Vicia gramines lectin, and by carbohydrate and amino acid compositions nearly identical to those of the glycoprotein epiglycanin present at the surface of the allotransplantable TA3-Ha ascites cell. By electron microscopic examination, TA3-MM epiglycanin appeared as long extended rods with widths (2.5 nm) and lengths (450--500 nm) similar to those of TA3-Ha epiglycanin. Incubation of each of two sublines of the TA3-MM ascites cell, TA3-MM/1 and TA3-MM/2, with a modified trypsin followed by column chromatography produced approximately 1.0- and 0.2-fold as much epiglycanin-like material, respectively, as was obtained from the TA3--a ascites cell. Continuous growth of the TA3-MM cell in suspension culture resulted in an almost complete disappearance of epiglycanin in a manner demonstrated earlier for the TA3-Ha cell grown under similar conditions. Allotransplantability in the TA3-MM cell may be due, at least in part, to masking a histocompatibility antigens by epiglycanin-like molecules.
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PMID:Isolation and partial characterization of an epiglycanin-like glycoprotein from a new non-strain-specific subline of TA3 murine mammary adenocarcinoma. 28 25

Pancreatic secretory abnormalities develop in most persons with pancreatic cancer and have been attributed to ductal obstruction. These experiments investigated whether abnormal secretion results instead from carcinogen-induced changes in the secreting cells. Fifty male Syrian Golden hamsters (40 to 100 grams) received weekly injections of di-isopropyl-nitrosamine (250 mg/kg, subcutaneously), and survivors and age-matched controls were studied after 3.5 to 6.5 months of treatment. Pancreatic secretion was stimulated by secretin or cholecystokinin (2 units/kg, intravenously, as a bolus). After each stimulus four 15-minute collections of pancreatic juice were analyzed for HCO3- and Cl- or total protein, amylase, trypsin, and chymotrypsin. The organs were examined histologically. Pancreatic ductal adenocarcinoma developed in 30% of the animals at 5 months, 56% at 5.5 months, and 100% at 6.5 months. The animals without cancer either had hyperplasia of the duct epithelium or were histologically normal. The histologic appearance of acinar tissue and protein secretion were normal in all groups. The tumors did not obstruct the major ducts. In all treated animals the pancreatic secretory response to secretin was of low volume, low maximal [HCO3-] and HCO3- output, and low [Cl- + HCO3-]; these changes progressed with time. The secretory abnormalities antedated the appearance of the neoplasms and were not caused by obstruction.
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PMID:Pancreatic secretion in hamsters with pancreatic cancer. 87 54

The pre-treatment with in vitro cultured mammary adenocarcinoma (ADK-1t) cells strongly protects syngeneic Balb/c mice against the challenge with the same non-cultured tumour cells. If the cultured cells were detached with sodium versenate, 50-60% protection was given, whereas if trypsin was used only 20-30% protection was achieved. That in vitro culture considerably reduces the oncogenic potential of ADK-1t cells was shown by the fact that very many more cultured than non-cultured cells were required to induce tumours.
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PMID:The effect of pre-treatment of syngeneic mice with tumour cells cultured in vitro on the induction of a transplantable tumour. 102 40

Cell surface structures of two mouse ascites tumors were studied using lectins. The tumors are sublines of the spontaneous mammary adenocarcinoma TA3 in strain A, differing in two main characteristics. Subline TA3-St grows only in syngeneic mice and has high expression of H-2 antigens. Subline TA3-Ha, in contrast, proliferates in all mouse strains, and has low amounts of exposed H-2 antigens. Concanavalin A (Con A), phytohemagglutinin (PHA) and Helix pomatia anti A hemagglutinin (HP) were used in agglutination tests, in binding experiments with 125I-labelled lectins and also in fluorescence studies with FITC-labelled lectins. Con A and PHA agglutinated the TA3-St cells but not the TA3-Ha cells. However, fluorescein-labelled Con A and PHA were bound to all cells (greater than 90%) of both sublines. Moreover both cell types contained an identical number of Con A receptors. The same result was obtained when the number of PHA receptors on the two sublines was compared. HP agglutinated TA3-Ha cells but not TA3-St cells. However, in this case, the difference in agglutinability between the lines was due to the presence or absence of HP receptors. All TA3-Ha cells contained large numbers of HP receptors. In contrast the majority (greater than 90%) of the TA3-St cells lacked HP receptors. (See article.) Trypsin released the HP receptors from TA3-Ha cells, at the same time making these cells agglutinable by both Con A and PHA. We conclude that the Ta3-Ha cells have a trypsin sensitive surface glycoprotein (or glycoproteins) detectable by HP, which is absent on most TA3-St cells. It is possible that this glycoprotein interferes with the agglutinability of TA3-Ha cells by Con A and PHA; whether it is also responsible for the low expression of H-2 alloantigen on this cell remains to be seen.
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PMID:Concanavalin A and other lectins in the study of tumor cell surface organization. 109 13

A major cell-surface glycoprotein of the TA3-Ha ascites mammary adenocarcinoma diminished during transfer from ascites growth to cell growth in suspension culture. A sensitive, hemagglutination-inhibition assay that used a lectin from Vicia graminea seeds indicated approximately a 50% loss after 7-10 days of culture and a 90% loss after 2 months. These findings were corroborated by carbohydrate and amino acid analysis with gas-liquid chromatography of trypsin glycopeptides released from the cell surface. Repassage of the cultured cells in vivo caused the reappearance of the surface glycoprotein.
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PMID:Reversible loss in suspension culture of a major cell-surface glycoprotein of the TA3-Ha mouse tumor. 123 14

Several of the cannabinoids found in marihuana have been shown to inhibit tumor growth and increase the life-span of mice bearing the Lewis lung adenocarcinoma. When trypsin-dispersed isolated Lewis lung cells are incubated in vitro, they maintain their capacity to carry out macromolecular synthesis (RNA, DNA, protein). This process can be inhibited by cytosine arabinoside, actinomycin D, or methyl-1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea, whereas cyclophosphamide, an agent that must be bioactivated, was inactive. Inhibition of DNA synthesis as measured by [3H]thymidine uptake into acid-insoluble material was used as an index of cannabinoid activity against isolated Lewis lung cells, L1210 leukemia cells, and bone marrow cells incubated in vitro delta9-, delta8-, 1-hydroxy-3-n pentyl-, and 1-delta8-tetrahydrocannabinol, and cannabinol demonstrated a dose-dependent inhibition of DNA synthesis whereas cannabidiol and 1-hydroxy-3-n-pentylcannabidiol were markedly less inhibitory in our in vitro cell systems. Furthermore, our in vitro observations with these cannabinoids are supported by in vivo tumor inhibition studies. Ring modifications as in cannabichromene or cannabicyclol abolish in vitro activity as does dihydroxylation at the 8beta and 11 positions of 1-delta9-trans-tetrahydrocannabinol. Delta9-trans-tetrahydrocannabinol demonstrated the least toxicity of all inhibitory cannabinoids in vivo; this is supported by its lesser effect on bone marrow DNA synthesis in vitro.
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PMID:The inhibition of DNA synthesis by cannabinoids. 124 11

Two murine colon adenocarcinoma cell lines were established from primary cultures. The MCA-38 cell line was begun by treatment of the primary culture with trypsin to remove the fibroblastoid elements. The MCA-36 epithelial cells were sensitive to trypsin; therefore, the growth medium of MCA-36 primary cultures was augmented with collagenase to release the tumor-cell elements from the fibroblast network. These tumor elements were dissociated with trypsin and placed in tissue culture. Each cell line was cultured for at least 10 passages in vitro and gave rise to tumors when reimplanted in vivo.
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PMID:Murine colon adenocarcinomas: methods for selective culture in vitro. 125 4


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