Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.1 (chymotrypsin)
 10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We produced a hybridoma designated 4G7 from a mouse immunized with chronic lymphocytic leukemia cells. The 4G7 hybridoma secretes an IgG1 antibody that is specific for normal and malignant B lymphocytes. Using dual color immunofluorescence staining, this antibody reacted with all immunoglobulin-positive cells but no T cells in normal peripheral blood. There was no detectable 4G7 antigen on monocytes, platelets, red cells, granulocytes, or phytohemagglutinin-activated T cells. When PBL were depleted of 4G7 positive cells and stimulated with pokeweed mitogen, secreted immunoglobulin levels fell to less than 10% of control values on Day 5 and less than 1% of control on Day 7. This antibody was reactive with 155 of 176 B lineage neoplasms on which it was screened. Thirty-five cases of myeloid or T-lymphoid malignancy were negative. Our studies show that the 4G7 antigen modulates in the presence of excess antibody. Free 4G7 antigen was not found circulating in human serum. The cell surface antigen identified by 4G7 was sensitive to pronase proteolysis but resistant to trypsin and chymotrypsin digestion. A comparison of 4G7 with other known B-cell antibodies indicates that the 4G7 antigen has not been previously identified. This antibody is of use for the identification of normal B lymphocytes, the study of B-cell differentiation, and the characterization of lymphoid malignancies.
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PMID:A unique human B lymphocyte antigen defined by a monoclonal antibody. 644 71

A protein that inhibits the replication of a malignant human mammary cell line, MCF-7, was purified to apparent homogeneity from human plasma-derived serum (PDS). Serum fractionation was accomplished by molecular sieve chromatography on Sephadex G-100 and Sephadex G-100 superfine columns. Further purification was accomplished by ion-exchange chromatography, with the use of DEAE-Sephacel followed by preparative polyacrylamide gel electrophoresis (PAGE) under nondenaturing conditions. Active fractions analyzed by sodium dodecyl sulfate (SDS)-PAGE showed one band with an apparent molecular weight of 53,000. Assays for the stability of those PDS fractions with the greatest growth-inhibitory activity and specificity for MCF-7 cells revealed that activity was retained during incubation at pH 2-10. Exposure to 6 M urea also had no effect on inhibitory activity. The activity was significantly reduced by incubation at 70 degrees C for 1 hour, exposure to 0.1% SDS, and treatment with chymotrypsin. Isoelectrofocusing showed two isoelectric points, 5.1 and 6.8.
J Natl Cancer Inst 1984 Feb
PMID:A factor from plasma-derived human serum that inhibits the growth of the mammary cell line MCF-7: characterization and purification. 658 17

Vegetarian populations show a decreased occurrence of breast, colon, and prostatic cancers. Epidemiological studies have identified seeds (maize, corn, and beans) as protective agents in these cancers. We have selected to study one abundant component of all seeds, protease inhibitors. Synthetic and natural protease inhibitors have been shown to inhibit tumor promotion in vivo and in vitro. In the present study, we report that a typical, natural protease inhibitor, the Bowman-Birk inhibitor isolated from soybeans, survives inactivation by stomach digestion in rodents and appears to be fully active as a protease inhibitor in the small intestine, where it complexes with the proteases occurring there, i.e., trypsin and chymotrypsin. A large part of the inhibitor is excreted as protease:protease inhibitor complexed in the feces. We also report the specific inhibition of transformation caused by ionizing radiation by this protease inhibitor. The mechanism of anticarcinogenesis of ingested protease inhibitors may involve the indirect effect of partially blocking protein absorption. High-protein and high-fat diets are known to increase cancer occurrence. Protease inhibitors reaching specific sites also have anticarcinogenic activities, as demonstrated by the radioprotective effect of a protease inhibitor in vitro. The relative importance of the indirect and direct action of protease inhibitors remains to be established.
Cancer Res 1983 May
PMID:Bowman-Birk soybean protease inhibitor as an anticarcinogen. 668 11

EGTA dissociated cell lines could be distinguished on the basis of their dependence on calcium during initial aggregation. However, the calcium-dependent aggregation could not be abolished by low chymotrypsin/EGTA treatment. These differences were not related to any morphogenetic property of the cells and suggest that different aggregation mechanisms are involved.
Cancer Lett 1982 Oct
PMID:Calcium-dependent and calcium-independent aggregation of established and malignant cell lines. 681 11

A tissue culture line of a human malignant melanoma, SEKI, induced cachexia in nude mice (BALB/c-nu/nu) (Kondo et al., Cancer Res., 41: 2912-2916, 1981). During the investigation of the cause of the cachexia, the melanoma was found to produce a protein immunologically identical to human alpha 1-antichymotrypsin (alpha 1-Ach). Tissues of the SEKI melanoma contained the protein immunologically equivalent to 0.29 +/- 0.11 (S.D.) mg of human alpha 1-Ach per g of wet tissue, while the other six human malignant tumors transplanted into nude mice did not contain a detectable amount of it. In the serum of nude mice bearing the melanoma, this protein appeared soon after the tumor growth occurred and gradually increased up to the level equivalent to 5 mg of human alpha 1-Ach per dl. Removal of the tumor resulted in a rapid decrease of the protein in the serum to an undetectable level within 1 day. This problem was never detected in the serum of nude mice bearing the other 27 human malignant tumors or controls. Purification of this protein was carried out by the column chromatography using DE-52, Blue-Sepharose, and SP-Sephadex. The elution patterns were the same as those of alpha 1-Ach in human serum, and the molecular weight of the protein was estimated as 69,000 by Sephadex G-100 column chromatography and 65,000 by polyacrylamide gel electrophoresis with sodium dodecyl sulfate. This purified protein, however, did not exhibit inhibitory activity against chymotrypsin. These results show that this melanoma produced a protein immunologically identical and physicochemically very similar to human alpha 1-Ach. This melanoma-nude mouse system may provide a useful model for investigating the synthesis of human alpha 1-Ach and analysis of its physiological roles.
Cancer Res 1982 Apr
PMID:Production of human alpha 1-antichymotrypsin-like protein by a human malignant melanoma transplanted into nude mice. 689 63

The assessment of exocrine pancreatic function by the oral administration of a chymotrypsin labile peptide N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) has proved to be an easy and reliable test of exocrine pancreatic function. It has the additional advantage that it can be used to study exocrine pancreatic function in all operative cases, even after gastrointestinal reconstruction. The recovery of p-aminobenzoic acid (PABA) correlates significantly with parameters of the PZ/CCK secretin (PS) test. Following Billroth II gastrectomy, the recovery of PABA decreased to 39.8 +/- 3.2% two weeks after and to 45.4 +/- 4.5% one to two months after operation, significantly lower than the 80.6 +/- 3.4% in normal subjects. In cases of cancer of the head of the pancreas, the exocrine function was 44.0 +/- 3.7%, and decreased to 17.5 +/- 3.0% after total pancreatectomy. Thus, BT-PABA enables a pertinent evaluation of pancreatic function in postoperative patients with various types of gastrointestinal reconstruction and also in cases when the PS test cannot be feasibly used.
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PMID:Evaluation of postoperative exocrine pancreatic function using chymotrypsin labile peptide. 698 66

A human colony-stimulating factor (CSF)-producing cell line, T3M-5, has been established in vitro from a squamous cell carcinoma of the thyroid gland transplanted into athymic nude mice [congenitally athymic BALB/c (nu/nu) mice; Central Institute for Experimental Animals, Kawasaki, Japan]. Contaminating fibroblasts derived from a host nude mouse were eliminated by treatment with antiserum raised against nude mouse cells. T3M-5 cells have been continuously propagated during 3 years. The cells grew in a monolayered sheet with about 22 hours of population-doubling time and showed about 40% plating efficiency. The cells exhibited an epithelium-like morphology resembling the structure of the original tumor and showed tumor takes when inoculated into nude mice. Chromosome analysis revealed the cell line to be a human aneuploid line with a hypertriploid mode. The cells possessed the characteristic function of human CSF production in vitro and produced marked neutrophilia in tumor-bearing nude mice that were inoculated with the cultured cells. The molecular weight of the CSF was estimated at about 27,000 and was stable over the pH range 1.0-9.0 at 4 degrees C for 21 hours. The CSF activity was destroyed by either trypsin or chymotrypsin, but it resisted neuraminidase, DNase, and RNase. The cells could be well propagated in roller bottles. About 100 liters of the conditioned medium was obtained with the roller bottle culture method, which formed approximately 500,000,000 colonies of human bone marrow cells. The rate of recovery of CSF activity from the gel-filtration column was high (68.9%). This cell line is therefore expected to aid in the large-scale preparation of human CSF.
J Natl Cancer Inst 1982 Dec
PMID:Establishment and characterization of a human colony-stimulating factor-producing cell line from a squamous cell carcinoma of the thyroid gland. 698 94

A continuous human cell line, COLO 357, with exceptional characteristics was derived from a metastasis of a pancreatic adenocarcinoma. COLO 357 grew as an adhering monolayer with a cell doubling time of 21 h and grew with 10% clonal efficiency in soft agar. COLO 357 cells had numerous lamellar inclusions. The cells elaborated the pancreatic enzymes trypsin, elastase and chymotrypsin. COLO 357 also secreted appreciable amounts of carcinoembryonic antigen and human chorionic gonadotropin. COLO 357 had a chromosome mode of 53 with 20 identifiable Giemsa-banded marker chromosomes. Nine nucleolar organizing regions were found by silver-stained metaphase preparations. COLO 357 has been "fingerprinted" for seven allelic isozymes. This cell line has been maintained in active culture for over 2 years, is preserved in a cell bank, and is available to other investigators.
Int J Cancer 1980 May 15
PMID:Human cell line (COLO 357) of metastatic pancreatic adenocarcinoma. 698 66

The diagnostic value of the fecal chymotrypsin test (FCT) was reevaluated with regard to (a) proved pancreatic hypofunction of different severity (183 pancreozymin-secretin tests); (b) the final clinical diagnosis, and (c) fecal fat excretion (208 patients with chronic pancreatitis; CP). Progressive pancreatic disease (cancer, CP) was mainly associated with moderate or severe pancreatic hypofunction (119/138; 86.2%) and a low incidence of false-normal FCT values (14/138; 10.1%). Miscellaneous disorders (mainly reversible pancreatic hypofunction) were mainly associated with slight pancreatic hypofunction and a high incidence of false-normal FCT values (17/45; 37.8%). Pancreatic steatorrhea (greater than 10 g/day) was found only in patients with markedly depressed FCT values. Progressive deterioration of pancreatic function was demonstrated by repeated FCT in CP (n = 220).
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PMID:Diagnostic value of the fecal chymotrypsin test in pancreatic insufficiency, particularly chronic pancreatitis: correlation with the pancreozymin-secretin test, fecal fat excretion and final clinical diagnosis. 725 May 49

Primitive biliary cells are known to migrate from the ductal plate into the mesenchyme during human intrahepatic bile duct development, and this migration process is essential for normal development of intrahepatic bile ducts. However, its molecular mechanism is unknown. Matrix proteinases play an important role in cell migration during cancer invasion and organ development. In this study, we therefore investigated in situ expression of matrix metalloproteinases (MMP) and tissue inhibitors of MMP (TIMP) during human intrahepatic bile duct development, using 32 human fetal livers. We also examined in situ expression of trypsinogen/trypsin, chymotrypsinogen/chymotrypsin, and cathepsin B, which are matrix proteinases and activators of MMP. MMP-1 expression was noted in the ductal plate and migrating primitive biliary cells. MMP-2, MMP-3, and MMP-9 were expressed in the ductal plate. TIMP-1 and TIMP-2 were expressed in the ductal plate and migrating primitive biliary cells. Trypsinogen/trypsin, chymotrypsinogen/chymotrypsin, and cathepsin B were also expressed in primitive biliary cells. These data suggest that MMP, trypsinogen/trypsin, chymotrypsinogen/chymotrypsin, and cathepsin B play a critical role in biliary cell migration during human intrahepatic bile duct development by degrading extracellular matrix proteins. The data also suggest that MMP inhibitors (TIMP-1 and TIMP-2) and MMP activators (trypsin, chymotrypsin, and cathepsin B) play an important role in biliary cell migration. The coordinated expression of MMP, MMP inhibitors, and MMP activators may be necessary for the normal development of human intrahepatic bile ducts.
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PMID:Expression of matrix proteinases during human intrahepatic bile duct development. A possible role in biliary cell migration. 748 84


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