Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) play a critical role in extracellular matrix homeostasis. We have previously cloned human and mouse TIMP-3 cDNAs and mapped their chromosomal loci (Apte, S. S., Mattei, M-G., and Olsen, B. R. (1994) Genomics 19, 86-90; Apte, S. S., Hayashi, K., Seldin, M. F., Mattei, M-G., Hayashi, M., and Olsen, B. R. (1994) Dev. Dynam. 200, 177-197); the identification of TIMP3 mutations in Sorsby's fundus dystrophy has underscored the functional importance of TIMP-3. We now report that TIMP-3 is encoded by five exons spanning over 30 kilobase pairs of mouse genomic DNA. In the attribution of protein domains to specific exons, as well as exon structures, the Timp-3 and Timp-1 genes are similar, confirming the common evolutionary origin of the TIMPs and defining a distinct gene family. We have expressed human and mouse TIMP-3 in mouse NSO myeloma cells. In each case, an N-glycosylated 27-kDa protein was generated, that, like TIMP-1 and TIMP-2, inhibited collagenase-1, stromelysin-1, and gelatinases A and B. TIMP-3 and TIMP-1 inhibition were quantitatively similar, implying that all TIMPs are equally efficient in MMP inhibition. Instead, differential regulation of the TIMP genes or divergent C-terminal protein sequences may underlie distinct biological functions for each TIMP.
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PMID:The gene structure of tissue inhibitor of metalloproteinases (TIMP)-3 and its inhibitory activities define the distinct TIMP gene family. 857 69

We developed a radioimmunoassay (RIA) for the carboxy-terminal telopeptides of type I collagen (ICTP), cross-linked with the helical domain of another type I collagen molecule, after isolation from human femoral bone. The cross-linked peptide was liberated by digesting insoluble, denatured bone collagen either with bacterial collagenase or with trypsin, and purified by two successive reversed-phase separations on HPLC, with monitoring of pyridinoline-specific fluorescence. The purity of the peptide was verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its origin in the type I collagen fibers was determined by amino-terminal amino acid sequencing. Polyclonal antibodies and a separation reagent containing second antibody and polyethylene glycol are used in the RIA. An immunologically identical, somewhat larger antigen is present in human serum; its concentration increases in multiple myeloma and in rheumatoid arthritis. The ICTP antigen seems to be cleared from the circulation by the kidneys, because glomerular filtration rates that are two-thirds of normal or less are associated with increased circulating ICTP concentrations. The CVs of the method are between 3% and 8% for a wide range of concentrations. The analysis of 40 serum samples can be completed in 4 h.
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PMID:Radioimmunoassay for the pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen: a new serum marker of bone collagen degradation. 847 58

Angiostatic substance TNP-470 displayed moderate cytotoxicity towards human leukemia HL-60, HL-60/ADR, HL-60/VCR and myeloma ARH77 cell lines with IC50 in the range 5-10 microM of concentrations and slightly higher IC50 for myeloma cell line U266. IC50 for ovarian CH-1, A2780 and A2780/ADR cell lines was in the range 10-15 microM with the exception of platinum-resistant SKOV3 cell line (more than 40 microM ). The IC50 values for MDA-MB-231 and MCF-7 breast carcinoma cell lines were 15 and 25 microM, respectively. In human hemopoietic neoplastic cell lines examined, TNP-470 induced the appearance of subpopulation with sub-G0 DNA content, suggesting the apoptosis-inducing potential of TNP-470 in these cells. No TNP-470-induced drug uptake modulation in drug-resistant leukemia cell line HL-60/VCR was observed. TNP-470 induced accumulation of cells in G0/G1 phase of cell cycle. There was no TNP-470-induced inhibition of MMP collagenase activity or MMP (MMP2 and MMP9) production in the human fibrosarcoma cells HT 1080 in vitro.
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PMID:Angiogenesis inhibitor TNP-470: cytotoxic effects on human neoplastic cell lines. 1066 43

Light (L) chain dimers expressed by multiple myeloma cells and collected as Bence-Jones proteins from the urine of human subjects were tested for their ability to form deposits in fibroblast monolayer cell cultures. Bence-Jones proteins from subjects with primary amyloidosis associated with L chains were shown to form fibrillar deposits by the in vitro assay introduced in this report. Filaments interspersed with nascent collagen could be detected after only 48 h. Deposition of L chains continued over a period of 72 h culminating in the appearance of dense fibrils with widths of 80-100 A and a variety of lengths. Formation of amyloid-like fibrils was accompanied by interference with the maturation of the collagen produced by the fibroblast cells. Fibrils composed of the Mcg lambda-type L chain were deposited between collagen fibers, thus expanding them laterally and leading to their partial disintegration. Mature collagen was completely missing from fibroblast monolayers exposed to the Sea lambda chain and the Jen kappa chain. Collagen with the characteristic striped pattern matured normally in control samples, such as those not dosed with amyloid precursors or those treated with a non-amyloidogenic Bence-Jones protein (e.g., the Hud lambda chain dimer). By immunochemical techniques using fluorescein- and gold-labeled anti-L chain antibodies, amyloidogenic L chains were shown to decorate the strands of nascent collagen. This observation suggests that amyloidogenic L chains are concentrated in the extracellular matrix by monovalent antigen-antibody type reactions. The capacity of the Mcg L chain dimer to bind collagen-derived sequences was tested by soaking crystals with a collagenase substrate, PZ-Pro-Leu-Gly-Pro-D-Arg. Difference Fourier analysis at 2.7 A resolution indicated that the PZ-peptide is a site-filling ligand. It could not be removed from the active site by perfusion of the crystal with ammonium sulfate crystallizing media. Similar experiments with the collagen-derived peptide (Pro-Pro-Gly)(5) showed substantial hysteresis effects extending from one end of the Mcg dimer to the other. After the ligand was withdrawn, the active site of the Mcg dimer could no longer bind the PZ-peptide. However, if the active site was first blocked by the PZ-peptide and subsequently exposed to the (Pro-Pro-Gly)(5) peptide, the difference Fourier map was indistinguishable from that obtained with the PZ-peptide alone. We concluded that amyloidogenic L chains such as the Mcg dimer could be concentrated in the perivascular space by binding to normal tissue constituents. These components include nascent collagen, which can be deterred from maturing as a result of this binding. Participation in such pathological activity is also self-destructive to the amyloidogenic L chains, which lose their binding capabilities for collagen-derived peptides and also become susceptible to irreversible conversion to amyloid fibrils. All of these events may be prevented by prior treatment of the amyloidogenic L chains with site-filling ligands. (c) 2000 John Wiley & Sons, Ltd.
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PMID:Binding of nascent collagen by amyloidogenic light chains and amyloid fibrillogenesis in monolayers of human fibrocytes. 1093 57

Recent clinical results from Edmonton have demonstrated the feasibility of achieving normoglycemia in type I diabetic patients by islet transplantation. One of the key issues in obtaining this success was transplanting sufficient numbers of islets by sequential transplants. Although the development of semipurified endotoxin-free Clostridium histolyticum-derived collagenase (Liberase) has improved islet yields from the human pancreas, batch-to-batch variation and loss of activity with time still hampers progress in obtaining consistent islet preparations. In order to define key components of crude collagenase, a panel of monoclonal antibodies (McAbs) was raised against crude collagenase. Monoclonal antibodies were generated by fusions between splenocytes of BALB/c mice immunized with Boheringer P collagenase and the myeloma cell line NS-0. These monoclonal antibodies were used as probes to study molecular differences between effective and ineffective collagenase batches using Western blotting. Two monoclonal antibodies (LDS71 and LDS81) were raised and characterized as recognizing separate epitopes on a 125-kDa component. Western blotting indicated that the 125-kDa band was rapidly broken down by storage or by dialysis in the presence of dithiothreitol. However, this breakdown could be prevented by the addition of leupeptin (a protease inhibitor) to the dialysis buffer. On testing fractions at 5-min intervals from the "Ricordi" digestion circuit during porcine and human pancreas digestion, the 125-kDa component was rapidly broken down in relatively ineffective collagenase batches but in effective batches was present throughout the digestion process. The correlation between the presence of the 125-kDa band and effectiveness of pancreas digestion suggests that this may be a key component in the formulation of C. histolyticum collagenase.
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PMID:Characterization of an important enzymatic component in collagenase that is essential for the effective digestion of the human and porcine pancreas. 1181 13


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