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)

The Hodgkin-associated Ki-1 antigen (CD30) consists of a 120-kDa membrane-associated glycosylated phosphoprotein (Ki-1/120) and a 57-kDa non-glycosylated phosphoprotein (Ki-1/57) which only occurs intracellularly. Both molecules are phosphorylated at serine residues. An analysis of the peptide fragments resulting from staphylococcal V8-protease digestion of the Ki-1/57 molecule revealed identical bands irrespective of the cell source. Only a few bands of the Ki-1/57 digests appeared among the peptide fragments of the Ki-1/120 membrane antigen. The protein kinase activity was tested for both forms of the Ki-1 antigen. The Ki-1/120, devoid of the Ki-1/57 molecule, was immunoprecipitated from cell lysates of Hodgkin-analogous cell lines L428 or L540, which had been loaded with the Ki-1 or the Ki-1-analogous antibodies Ber-H2, HSR-1, -2 and -3 (method 1). These other antibodies reacted with the Ki-1/120, but not with the Ki-1/57 antigen. The latter, devoid of the Ki-1/120, was isolated from L540 cells after removal of the membrane form by method 1 or from U266/Bl myeloma or Raji Burkitt lymphoma cells which only contain the smaller form. Effects of non-specific adsorption were eliminated by various control precipitates. The Ki-1/57 intracellular antigen showed autophosphorylation and could phosphorylate histones as well. In contrast, a protein kinase activity of the membrane-associated Ki-1/120 could not be demonstrated.
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PMID:Protein kinase activity of the intracellular but not of the membrane-associated form of the Ki-1 antigen (CD30). 216 Nov 15

The Hodgkin-associated Ki-1 antigen occurs in two different molecular forms. The 120-kDa membrane-associated form is a phosphorylated glycoprotein, which is derived from a non-phosphorylated intracellular 84-kDa apoprotein that is co-translationally N-glycosylated with a carbohydrate portion of 6 kDa. The other form of the Ki-1 antigen is a non-glycosylated phosphoprotein of 57 kDa which only occurs intracellularly. Both forms of the antigen are phosphorylated at serine residues. Enzymatic cleavage with sialidase reduced the 120-kDa membrane antigen by about 15 kDa, while its 90-kDa precursor and the 57-kDa intracellular form of the Ki-1 antigen remained unaltered. Pulse-chase experiments revealed that the 57-kDa and 90/120-kDa molecules are synthesized independently of each other. Four to eight hours after synthesis, the degradation of the 120-kDa molecule to a 105-kDa membrane-associated intermediate begins. This is further processed and appears in the cell supernate as a 90-kDa molecule. Hodgkin's disease-derived, Epstein-Barr virus-transformed cell lines and the acute T cell leukemia line MOLT-4 contain both forms of the Ki-1 antigen, whereas only the 57-kDa intracellular antigen is expressed in U266/B1 myeloma cells, in the Burkitt lymphoma cell lines Raji and Daudi and in acute promyelocytic HL-60 leukemia cells.
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PMID:The Hodgkin-associated Ki-1 antigen exists in an intracellular and a membrane-bound form. 254 29

We earlier identified a variant of CD30 (CD30v) that retains only the cytoplasmic region of the authentic CD30. This variant is expressed in alveolar macrophages. CD30v can activate the nuclear factor-kappaB (NF-kappaB) as CD30, and its overexpression in HL-60 induced a differentiated phenotype. To better understand the physiological and pathological functions of CD30v, expression of this variant was examined using a multiple approach to examine 238 samples of human malignant myeloid and lymphoid neoplasms. Screening by reverse transcriptase-polymerase chain reaction (RT-PCR) revealed expression of CD30v transcripts in 52 of 72, 7 of 11, 63 of 90, and 7 of 30 samples of acute myeloid leukemia (AML), myeloid blast crisis of myeloproliferative disorders (MBC), and lymphoproliferative disorders (LPDs) of B- and T-cell origin, respectively. CD30v expression was high in monocyte-oriented AMLs (FAB M4 and M5), B-cell chronic lymphocytic leukemia (B-CLL), and multiple myeloma (MM). Using the specific antibody HCD30C2, prepared using a peptide corresponding to the nine amino acids of the amino-terminal CD30v, expression of CD30v protein was detected in 10 of 25 and 2 of 10 AML and ALL samples, respectively. In AMLs, immunocytochemical detection of CD30v revealed the presence of loose clusters of CD30v-expressing cells dispersed amid a population of CD30v-negative blasts. Finally, the parallel expression of CD30v mRNA and protein, as evidenced by Northern and Western blotting, was confirmed in selected cases of AMLs and LPDs. A significant correlation was found between expressions of CD30v and CD30 ligand transcripts in AML and LPD (P = 0.02, odds ratio = 3.2). The association of CD30v with signal-transducing proteins, tumor necrosis factor receptor-associated factor (TRAF) 2, and TRAF5 was demonstrated by coimmunoprecipitation analysis, as was demonstrated for authentic CD30 protein. Expression of transcripts for TRAF1, TRAF2, TRAF3, and TRAF5, as demonstrated by RT-PCR, was noted in leukemic blasts that express CD30v. Collectively, frequent expression of CD30v along with TRAF proteins in human neoplastic cells of myeloid and lymphoid origin provide supportive evidence for biological and possible pathological functions of this protein in the growth and differentiation of a variety of myeloid and lymphoid cells.
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PMID:Frequent expression of the variant CD30 in human malignant myeloid and lymphoid neoplasms. 1059 33