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)

In the previous communication (Mellis, S. J., and Baenziger, J. U. (1983) J. Biol. Chem. 258, 11546-11556), the structures of the oligosaccharides present at the 3 asparagine glycosylation sites of a human IgD myeloma protein were defined. In this communication, we present the structures of the O-glycosidically linked oligosaccharides located in the hinge region of IgD:WAH. Three or four threonine residues and one serine residue in the region bear O-glycosidically linked oligosaccharides. Approximately 50% of these molecules have the structure Gal beta 1 leads to 3 GalNAc which is identical with the structure of the predominant oligosaccharide in the hinge region of human IgA1 myeloma proteins (Baenziger, J. U., and Kornfeld, S. (1974) J. Biol. Chem. 249, 7270-7281). The remainder of the oligosaccharides contain 1 or 2 residues of N-acetylneuraminic acid and have the structures NeuAc alpha 2 leads to 3Gal beta 1 leads to 3GalNAc (30%), Gal beta 1 leads to (NeuAc alpha 2 leads to 6)GalNAc (12%), and NeuAc alpha 2 leads to 3Gal beta 1 leads to 3(NeuAc alpha 2 leads to 6)GalNAc (8%). The sialylated molecules have not been encountered previously on other human immunoglobulin heavy chains. These structures, however, have been described on a number of secreted and membrane glycoproteins. Examination of oligosaccharides isolated from different subregions of the IgD hinge indicated that a specific distribution of the sialylated structures among the glycosylated amino acids of the hinge region is not likely.
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PMID:Structures of the O-glycosidically linked oligosaccharides of human IgD. 661 28

Pure secretory immunoglobulin A was isolated from human milk by fractionation in gradients of pH and (NH4)2SO4 concentration followed by gel filtration. The hinge region containing all the O-glycosidically linked oligosaccharides was isolated en bloc after trypsin and pepsin hydrolysis and separated by gel filtration. The mixture of O-glycosidically linked oligosaccharides contained N-acetylneuraminic acid (NeuAc), fucose (Fuc), galactose (Gal), N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc) in the molar ratio of 0.2:0.5:2.5:2:1 respectively. After beta-elimination several oligosaccharides were separated by a combination of ion-exchange chromatography and gel-filtration chromatography. The complete structure of four of these oligosaccharides was determined by methanolysis, methylation and mass spectrometry. The structure of the four oligosaccharides which are linked to serine or threonine residues of the hinge region are as follows: beta-Gal-(1 leads to 3)-GalNAc-ol; alpha-HeuAc-(2 leads to 3)-beta-Gal-(1 leads to 3)-GalNAc-ol; beta-Gal-(1 leads to 3)-[beta-GlcNAc-(1 leads to 6)]-GalNAc-ol; beta-Gal-(1 leads to 3)-[beta-Gal-(1 leads to 4)-beta-GlcNac-(1 leads to 6)]-Gal-NAc-ol. These oligosaccharides are more complex and heterogenous than the oligosaccharides linked to serine residues of the hinge region from myeloma serum immunoglobulin A1.
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PMID:Heterogeneity of the glycans O-glycosidically linked to the hinge region of secretory immunoglobulins from human milk. 721 51

The 72-kDa spleen tyrosine kinase (Syk) and Src-family kinase p53/56Lyn (Lyn) contribute to signaling via the B-cell antigen receptor complex. Here we show that Syk and Lyn from human B lymphocytes can interact directly. Syk and Lyn coimmunoprecipitated from mature and activated B-cell lines, and gel-purified Syk and Lyn reassociated in vitro, demonstrating their direct interaction. This Syk-Lyn interaction may be dependent on the stage of B-cell differentiation, since Syk-Lyn associations were not detected in pre-B and myeloma cell lines and Syk from an immature B-cell line did not reassociate with Lyn in vitro. Serine/threonine kinase activity was also associated with Syk. Crosslinking of cell surface IgM led to rapid activation of both tyrosine and serine/threonine protein kinase activities that resulted in phosphorylation in vitro of proteins coprecipitating with Syk--in particular, a serine/threonine phosphorylated protein 120 kDa in size (pp120). Several phosphoproteins, including one of 72 kDa and one of 120 kDa, coprecipitated with phospholipase C-gamma 1 (PLC gamma 1). Sequential immunoprecipitation identified the 72-kDa protein associated with PLC gamma 1 as Syk. The 120-kDa serine/threonine phosphorylated protein that coprecipitated with PLC gamma 1 resembled the Syk-associated pp120 by several criteria. Thus, pp120 may serve as a link between Syk and PLC gamma 1, coupling the B-cell antigen receptor to the phosphatidylinositol pathway.
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PMID:Human spleen tyrosine kinase p72Syk associates with the Src-family kinase p53/56Lyn and a 120-kDa phosphoprotein. 783 Dec 90

The cDNA encoding for the human FA-1 sperm antigen was cloned and sequenced from the in-house constructed subtractive human testis cDNA expression library in lambda Ziplox using the FA-1 monoclonal antibody (mAb). The full--length sequence was obtained by using the 5' rapid amplification of 5'-cDNA end (5'-RACE) procedure. It is 1,576-bp long, and has an open reading frame (ORF) of 283 amino acids (aa) with the first ATG Met start codon at nucleotide (nt) 57 and the stop codon TAG at nt 906. It has two termination codons at the 5' end before the ATG start codon. The translated protein has a calculated molecular weight of 32.1 kDa and estimated isoelectric point (pI) of 11.59. It has one potential N-linked glycosylation site and one tyrosine phosphorylation site, besides several O-linked glycosylation and serine and threonine phosphorylation sites. Hydrophilicity analysis of the deduced aa sequence showed it to be a membrane-anchored protein. Extensive computer search in the database did not identify any known nt/aa sequence having homology with FA-1 cDNA or deduced aa, indicating it to be a novel gene. The Northern blot and reverse transcription-polymerase chain reaction (RT-PCR)-Southern blot analyses indicated the testis-specific expression of FA-1 antigen at the mRNA level. The ORF of the FA-1 was subcloned into pGEX- 1lambda T for expression. The expressed FA-1 recombinant protein had a molecular size of approximately 40 kDa, and was recognized by the FA-1 mAb, and not by the myeloma control Ig. The rabbit antibodies (Ab) raised against the recombinant (r) FA-1 antigen recognized the rFA-1 antigen as well as the native (n) FA-1 antigen. The rFA-1 Ab specifically recognized a protein band of approximately 50 kDa in human testis extract in the Western blot involving 11 types of human tissue extracts, indicating the testis-specific expression of FA-1 at the protein level. The Ab showed binding with live and methanol-fixed human sperm at the post-acrosomal, mid-piece, and tail regions. The Ab caused a significant (P < 0.001) and concentration-dependent inhibition of human sperm capacitation/acrosome reaction by blocking tyrosine phosphorylation of the FA-1 antigen. The sperm-specific human FA-1 recombinant antigen may find applications in immunocontraception, and diagnosis and treatment of immunoinfertility in humans.
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PMID:Molecular cloning and sequencing of cDNA encoding for human FA-1 antigen. 1220 36

The interleukin-6 (IL-6) signaling pathway contributes to myeloma cell growth and viability through activation of the PI3/Akt kinase pathway. To understand the downstream signaling elements in the PI3/Akt kinase pathway that are involved in the regulation of myeloma cell growth, we determined the role played by glycogen synthase kinase 3 (Gsk3) and forkhead transcription factors (FH) in the RPMI-8226 myeloma cell line. We demonstrate that both Gsk3 and FH transcription factors FKHRL1 (FOX3a), FKHR (FOXO1a), and AFX (FOXO4) are phosphorylated (inactivated) by IL-6. Further, we show that inhibitors of Gsk3 induce dephosphorylation of FKHRL1 and FKHR at their threonine sites and upregulate the cyclin-dependent kinase inhibitor p27(kip1). Finally, we show that inhibition of Gsk3 activity is sufficient to suppress cell growth and induce apoptosis thus overriding the effects of IL-6 in myeloma cells.
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PMID:Regulation of myeloma cell growth through Akt/Gsk3/forkhead signaling pathway. 1235 17

Among the Bcl-2 family, myeloid cell leukemia-1 (Mcl-1) distinguishes itself from the other pro-survival proteins by its ability to oppose to a wide variety of pro-apoptotic stimuli, short half-life, and presence of polypeptide sequences enriched in proline (P), glutamic acid (E), serine (S) and threonine (T) domains (PEST). Moreover, Mcl-1 undergoes a complex transcriptional, post-transcriptional, and post-translational regulation process. This regulation modifies not only Mcl-1 expression, but also its function. Various extra-cellular stimuli, including cytokines, growth factors, 12-O-tetradecanoyl-phorbol 13-acetate (TPA) and IFN, activate pathways which regulate Mcl-1 expression. Furthermore, Mcl-1 can be alternatively spliced into a long (Mcl-1) or a short (Mcl-1S) form. Mcl-1 opposes pro-apoptotic proteins and can be either cleaved or phosphorylated at a post-translational level. Mcl-1-spliced products, Mcl-1-cleaved products, or phosphorylated Mcl-1 have either a pro or an anti-apoptotic function, highlighting the complexity and pivotal role of Mcl-1 regulation. Here we discuss the regulation and function of Mcl-1 in the pathophysiology of multiple myeloma.
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PMID:Mcl-1 regulation and its role in multiple myeloma. 1546 63

Proteasome inhibitors represent novel anti-cancer drugs which interact with the proteasome-ubiquitin pathway. The 26S proteasome is a multicatalytic threonine protease with three distinct catalytic activities. It is responsible for intracellular protein turnover in eukaryotic cells, including the processing and degradation of short- and some long-living proteins required for regulation of various cellular functions. Subsequently, the inhibition of the proteasomal function results in stabilization and accumulation of its substrates, which notably include cyclins, cyclin-dependent kinase inhibitors, transcriptional factors, tumor suppressor proteins and proto-oncogenes. This results in confounding signals in the cell inducing cell cycle arrest and activation of apoptotic programs. Acting on transcriptional factor NF-kappaB, which is upregulated in some tumors undergoing chemotherapy or irradiation and downregulated by proteasome inhibition, a significant chemosensitization and consequently synergistic effects concerning the anti-tumor activity could be achieved. Bortezomib is the first proteasome inhibitor that has entered clinical trials. In multiple myeloma, both the US Food and Drug Administration and European Medicine Evaluation Agency granted approval for the use of bortezomib (Velcade) for the treatment of multiple myeloma patients who have received at least two prior therapies and have demonstrated disease progression on the last therapy. At present, other trials examine the activity in a variety of solid tumors and hematological malignancies. This paper reviews preclinical and clinical results.
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PMID:Proteasome: an emerging target for cancer therapy. 1584 12

The fast-track approval of a proteasome inhibitor, PS-341, to treat multiple myeloma spurred a wave of interest in both the proteasome itself and small-molecule compounds blocking its activities. Besides being candidates for drugs against cancer, autoimmune diseases, inflammation, or stroke, specific proteasome inhibitors are indispensable tools for biochemical and cell biology investigations of the proteasome and proteasome-ubiquitin system. Numerous synthetic peptide derivatives, such as boronates, epoxides, aldehydes, vinyl sulfones, cyclic peptides, and lactones, block the N-terminal threonine-type active centers of the enzyme, halting the cleavage of proteasomal protein substrates both in vitro and in vivo. Because some of the proteasomal inhibitors exhibit a high specificity toward only one particular type of an active center of the proteasome, they constitute valuable probes for testing the mechanism of proteolysis catalyzed by the enzyme. In this chapter we discuss the most common applications of available proteasome inhibitors. In addition to the best-known competitive inhibitors, we also describe the benefits from the use of allosteric inhibitors, which induce distinct but less understood in vitro and in vivo effects on the proteasomal machinery. Finally, we present the application of the basic biochemical procedures to decipher the mechanism of interactions of a novel compound with the proteasome.
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PMID:Small-molecule inhibitors of proteasome activity. 1591 22

The 26S proteasome is a multicatalytic threonine protease complex that is responsible for intracellular protein turnover in eukaryotic cells. This complex degrades and processes proteins required for regulation of various cellular functions. Bortezomib is a novel proteasome inhibitor approved for therapy of multiple myeloma. Inhibition of ubiquitin-proteasome-mediated protein degradation by bortezomib leads to accumulation of its diverse substrates, including cyclins, transcriptional factors, tumor suppressor proteins, and protooncogenes. The sequelae of such profound perturbation of cellular function include cell cycle arrest and activation of apoptotic programs. As the development of this agent continues, there is interest in evaluating its interaction with other anticancer agents. This review provides an overview of selected interactions between bortezomib and other anticancer agents preclinically and in early clinical trials.
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PMID:Sequencing bortezomib with chemotherapy and targeted agents. 1625 Sep 28

Arsenic is a pathologic factor of cardiovascular diseases and cancers; nevertheless, it also acts as an anticancer agent effective on acute promyelocytic leukemia and multiple myeloma. Securin, a proposed proto-oncogene, regulates cell proliferation and tumorigenesis. However, roles of securin on the arsenic-induced cell cycle arrest and apoptosis remain unknown. In this study, the effects of sodium arsenite on the expression of securin in two tissue types of cell lines, the vascular endothelial and colorectal epithelial cells, were investigated. Arsenite (8-16 microM, 24 h) increased the cytotoxicity, apoptosis, and growth inhibition in both endothelial and epithelial cells. The levels of phospho-CDC2 (threonine-161), CDC2, and cyclin B1 proteins were decreased, and the G2/M fractions were increased by arsenite. Concomitantly, arsenite markedly diminished the securin protein expression and induced the abnormal sister chromatid separation. The depletion of securin proteins increased the induction of mitotic arrest, aberrant chromosome segregation, and apoptosis after arsenite treatment. p53, a tumor suppressor protein, balances the cell survival and apoptosis. Arsenite raised the levels of phospho-p53 (serine-15) and p53 (DO-1) proteins in both the securin-wild-type and -null cells. The p53-functional cells were more susceptible than the p53-mutational cells to arsenite on the cytotoxicity and apoptosis. Besides, arsenite decreased the levels of securin proteins to a similar degree in both the p53-functional and -mutational cells. Together, it is the first time to demonstrate that the inhibition of securin expression induced by arsenite increases the chromosomal instability and apoptosis via a p53-independent pathway.
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PMID:Depletion of securin increases arsenite-induced chromosome instability and apoptosis via a p53-independent pathway. 1633 54


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