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)

Three human cell lines from adenocarcinomas of the extrahepatic biliary tract were established in permanent tissue culture. Mz-ChA-1 and Mz-ChA-2 were cultured from mechanically dissociated gallbladder adenocarcinoma metastases and SK-ChA-1 was grown from malignant ascites of a patient with primary adenocarcinoma of the extrahepatic biliary tree. Cell doubling times in tissue culture are 3-4 days for Mz-ChA-1 and approximately 2 days for Mz-ChA-2 and SK-ChA-1. All three tumour cell lines were successfully transplanted to nude mice, inducing progressive tumour growth. Histologically, nude mouse tumours resembled the original adenocarcinomas. In vitro formation of gland-like structures were regularly seen in Mz-ChA-1 and Mz-ChA-2 but only occasionally in SK-ChA-1. All three cell lines formed contacts through interdigitating processes with desmosomes and junctional complexes. On scanning electron microscopy, an abundance of microvilli was seen at the cell surfaces. Chromosome analyses of all three tumour cell lines showed a wide range of numerical abnormalities and presence of marker chromosomes. Mz-ChA-1 appears to be highly differentiated with cells producing mucus. Mz-ChA-2 synthesizes components of complement C2, C3 and C5, while Mz-ChA-1 and SK-ChA-1 produce only C3 in detectable quantities. In addition, Mz-ChA-2 supernatants are positive for ferritin and alpha 1-fetoprotein, but not CEA; while Mz-ChA-1 and SK-ChA-1 produce only CEA. Supernatants of all three cell lines are positive for N-acetyl neuraminic acid (NANA), phosphohexoisomerase (PHI) and LDH, and negative for alpha 2-macroglobulin, alpha 1-anti-trypsin, gamma-GT, AP, coeruloplasmin, haptoglobin and albumin. A high cloning efficiency renders these new tumour cell lines suitable for continued studies on clonal heterogeneity in malignant tumours. The establishment of these cell lines in tissue culture facilitates further studies on the biology of upper gastrointestinal tract cancer in man.
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PMID:Biliary adenocarcinoma. Characterisation of three new human tumor cell lines. 405 57

Two clonal tumor subpopulations (designated as A and D) obtained originally from a heterogeneous human colon adenocarcinoma (DLD-1) were used to produce xenograft solid tumors in nude mice. First, disaggregation studies were performed to determine the optimal choice of enzyme and time of dissociation for the pure A and D neoplasms, using cell yield (cells/mg/min) and colony forming efficiency (CFE) assays. The enzymes investigated were: 0.5 or 0.2% trypsin, and two cocktails containing pronase (0.5 or 0.05%), collagenase (0.02%), and DNAse I (0.02%). For the 0.5% trypsin treatments, the cell yield from A and D tumor fragments increased until about 30 min, at which time a plateau in cell yield was reached. A plateau in CFE was also reached at this time. In contrast, the cell yields for the 0.2% trypsin treatment did not reach a plateau within the time of the dissociation (120 min), and the CFEs were lower than with the 0.5% trypsin. Whereas no differences in cell yield or CFE were found between the enzyme cocktail studies (0.5% trypsin vs. 0.05% pronase), the cell yield and the CFE from the clone D carcinomas were significantly less than that found with the 0.5% trypsin (the cell yield and CFE from clone A tumors were identical for 0.5% trypsin or enzyme cocktail). These data indicate that, while these clonal neoplasms have somewhat different responses to enzyme disaggregation, it is possible to select an enzyme treatment and treatment time that is appropriate for use on both A and D tumors (i.e., 0.5% trypsin). After determination of an acceptable enzyme procedure, 'reconstructed' heterogeneous tumors produced from an initial injection bolus of 50% clone A and 50% clone D cells were disaggregated as a function of time (days 12-83 postinjection). Over this period, we found that the cell yield decreased exponentially, with a half-time (T1/2) of 20.5 +/- 7.3 days (95% confidence limits), with a maximum extrapolated cell yield at time zero of about 1.2 X 10(5) cells/mg. The CFE was essentially constant over the duration of the assay period. Moreover, it was found that the percentage of clone A cells appeared to decrease exponentially (T1/2 = 20.5 +/- 11.5 days, 95% confidence limits) until about 40 days postinjection. After this time an equilibrium mixture consisting of about 10% clone A cells and 90% clone D cells was reached.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Disaggregation studies of xenograft solid tumors grown from pure or admixed clonal subpopulations from a heterogeneous human colon adenocarcinoma. 406 5

Previous studies have demonstrated that a unique glycoprotein can be cleaved by trypsin from the plasma membrane of the Ha, but not the St, subline of the TA(3) murine mammary adenocarcinoma. Using an automated quantitative method for measurement of trypsincleaved fragments (glycoprotein fraction I) by inhibition of Vicia graminea lectin hemagglutination, we find evidence that glycoprotein fraction I-like molecules appear in the ascites fluid and serum of the Ha-bearing, but not the St-bearing, syngeneic mice. These molecules were shown by gel filtration to be larger than the trypsincleaved glycoprotein fraction I but have a carbohydrate composition very similar to glycoprotein fraction I. It is likely that these ascites and serum glycoproteins have been released in vivo from the membranes of the viable Ha tumor cells. In view of the ability of the Ha, but not the St, cells to grow in allogeneic recipients, it is possible that these circulating membrane-derived molecules may be playing a blocking role in the immune response to the tumor.
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PMID:In vivo release of glycoprotein I from the Ha subline of TA3 murine tumor into ascites fluid and serum. 452 34

After incubation with an encephalitogenic factor from human (HEF) or rat (REF) brain, lymphocytes of Fischer 344 rats bearing a spontaneous mammary adenocarcinoma produced a soluble substance which reduced the mobility of tanned sheep red blood cells in the electrophoretic mobility test (EMT). For studying the kinetics of this lymphocyte response, 6 X 10(5) tumor cells were injected into the hind footpad. In correlation with time and tumor size, one was able to influence the appearance of metastases by amputation of the leg. As early as 16 hours after inoculation of tumor cells, sensitivity of lymphocytes against HEF and a KCl-extract of the tumor could be shown in the EMT. It decreased on days 2 and 5, but was still seen until the day of amputation. Rats without metastases showed sensitivity up to four weeks after amputation and then returned to normal levels. Rats with metastases showed sensitivity until death at about seven weeks later. With the use of Amicon membranes, Sephadex G-50, and ion-exchange chromatography, a protein could be isolated from human basic myelin extract with a molecular weight of about 16,000-20,000 daltons. It had no direct influence on the EIC by itself, but after incubation with lymphocytes from tumor-bearing rats it evoked the production of a slowing substance. Using Sephadex G-100, the slowing substance appeared in the region in front of BSA indicating a molecular weight of greater than 80,000 daltons. It was heat-stable for 30 min at 56 degrees C and was sensitive to trypsin.
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PMID:Electrophoretic mobility test (EMT): studies on lymphocyte response and mechanism of the test using a rat tumor model. 616 95

By using four distinct monoclonal antibodies to CEA, the molecular profile of which was clarified in our accompanying companion paper, immunohistochemical distribution of the antigenic determinants on both cancerous and noncancerous tissues as well as fetal tissues was studied with the use of the immunoperoxidase method. All of the monoclonal antibodies recognize different antigenic determinants on the tissue section. None of the antibodies stained granulocytes in the peripheral blood or in the normal liver tissues tested. Three of our monoclonal antibodies stained columnar epithelial cells in morphologically normal colonic mucosa; however, monoclonal antibody YK024 did not stain them. This antibody was also found to be unreactive with intestinal metaplasia lesions of the stomach, but reacted with a 16-wk-old fetal stomach as well as with cancerous parts of the colon and of the stomach. Moreover, it was found that this monoclonal antibody mainly reacted with moderately or poorly differentiated adenocarcinoma lesions of the colon and the stomach. Periodic acid treatment in this study, together with trypsin treatment on the antigen as described in our accompanying companion paper, may suggest that this antibody recognizes the carbohydrate antigenic determinant in nature.
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PMID:Immunohistochemical distribution of the antigenic determinants detected by monoclonal antibodies to carcinoembryonic antigen. 620 70

We succeeded in an establishment of a human pancreatic cancer cell line (PK-1) from liver metastasis of pancreatic cancer. Primary pancreatic cancer cells grew as islands surrounded by fibroblastic cells. However, these fibroblastic cells were gradually omitted by the polygonal shaped cancer cells. This cell line contained neither zymogen granules nor trypsin indicating that this pancreatic cancer originated from pancreatic duct cells. Modal chromosome numbers of this cell line were 42 and 72 and the doubling time was 48 hr. This cell line was transplantable in athymic nude mice to form progressive tumors which had histology similar to that of the original cancer (papillotubular adenocarcinoma). Neither AFP nor ferritin but CEA was detected on the surface and in the cytoplasm of this cell line in indirect immunofluorescence. Rabbit antiserum against this pancreatic cancer cell line detected pancreatic cancer associated antigen besides CEA in the culture supernatant. This antiserum reacted with sera from patients with pancreatic cancer to form a distinct precipitin line in agarose gel which fused with the precipitin line formed between the culture supernatant of this cell line and the antiserum.
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PMID:Establishment of a human pancreatic cancer cell line and detection of pancreatic cancer associated antigen. 620 69

A spontaneous mammary adenocarcinoma (AC) from an inbred female rat was investigated with regard to secretion of neutral proteases. Cultures of neoplastic epithelial cells derived from the tumour secreted an enzyme that fulfilled the criteria for a specific collagenase. In contrast to cultures of non-neoplastic cells, tumour collagenase was present as an active enzyme, since treatment with trypsin or p-aminophenylmercuric acetate (APMA) did not increase activity. The neoplastic cells were also prolific producers of plasminogen activator (PA). Dexamethasone (Dex) (10(-6)M) markedly reduced the levels of both enzymes. Addition of tranexamic acid (TA), an inhibitor of plasmin and of plasminogen activation, did not affect collagenase activity, even at 10(-1)M TA, nor did latent collagenase accumulate. Latent collagenase was secreted in culture by normal fibroblasts from neonatal rat lungs. This latent enzyme was activated by the addition of tumour cell medium plus plasminogen, but this effect was inhibited by the addition of TA. These results demonstrate that the neoplastic cells themselves secrete collagenase as an active enzyme. PA is also secreted, is not involved with tumour collagenase, but is capable, in the presence of plasminogen, of activating latent collagenase produced by the non-neoplastic cells within the tumour or in the surrounding tissue. This tumour possesses potent collagenolytic ability in vitro which may be partly responsible for its rapid invasion in vivo.
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PMID:Rat mammary carcinoma cells secrete active collagenase and activate latent enzyme in the stroma via plasminogen activator. 627 36

We have systematically analyzed the proliferative properties of the clonogenic cells of the R3327 transplantable rat prostate adenocarcinoma (colony forming units, prostatic adenocarcinoma, CFU-PA). Pronase was determined to be more effective than either trypsin or collagenase in obtaining the largest number of viable cells from a solid R3327 tumor. Digestion with 2.5 mg/ml yielded a maximum of 5.6 X 10(4) CFU-PA/g of tumor tissue, with higher concentrations resulting in s substantially lower fraction of CFU-PA while producing larger overall cell yields. Bacto-agar at 0.35% supported the growth of the largest number of CFU-PA and was sharply concentration dependent with concentrations greater than 0.4% completely suppressing CFU-PA growth. The addition of conditioned medium (CM) from R3327 liquid cell cultures to agar cultures resulted in a specific twofold increase in CFU-PA/10(4) cells, whereas CM from R3327A cells was less effective and CM from rat skin fibroblasts least stimulatory. The addition of washed rat red blood cells (RBC) either within the agar culture itself or in an overlayer was highly stimulatory, resulting in as much as a fivefold increase in CFU-PA to 6 to 8 x 10(4)/g.
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PMID:Proliferative properties of the clonogenic cells of the R3327 prostate adenocarcinoma. 633 74

Serum-free medium conditioned by activated cells of the acute monocytic leukemia line, THP-1, was examined for growth-inhibitory activity with several established human cell lines. Free-floating clusters of THP-1 cells were activated into adherent nonproliferating cells by a 24-hr exposure to 10(-7) M mezerein in Roswell Park Memorial Institute 1640 medium containing 1% fetal bovine serum. Adherent cells were incubated for an additional 24 hr in serum-free medium containing insulin (5 micrograms/ml). Dose-response studies revealed that a cervical carcinoma (HeLa), a melanoma (A375Ag5), and several mammary carcinoma cell lines (MCF-7, BT474, MDA-MB415, and T47D) were growth inhibited by this conditioned medium. We concluded, from the results of thymidine release assays and from experiments on reversibility, that inhibition was a cytostatic and not a cytolytic response. In contrast, THP-1 conditioned medium stimulated the growth of two mammary lines (ZR75-1 and HBL-100), a lung type II carcinoma (549), and a colon adenocarcinoma (SW48). Preliminary characterization showed that the inhibitory activity was stable to acid and urea treatment but was destroyed by trypsin and sodium dodecyl sulfate. Molecular sieve chromatography of acetic acid-extracted material separated the inhibitory and stimulatory components.
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PMID:Production of growth-inhibitory activity in serum-free medium by human monocytic leukemia cells. 634 88

The formation of tight junctions can be induced in the human adenocarcinoma cell line HT 29 by treatment with trypsin at 37 degrees C. In contrast, after treatment of the cells with trypsin at low temperature (3 degrees C), no tight junctions were observed. However, abundant formation of tight junctions occurred when cells were treated with trypsin at 3 degrees C, washed with soybean trypsin inhibitor, and subsequently incubated at 37 degrees C. Thus, this protocol allows for the first time the temporal separation of the induction and assembly of tight junctions.
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PMID:Separation of induction and expression of tight junction formation mediated by proteinases. 636 64


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