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
Query: UMLS:C0026764 (
multiple myeloma
)
36,148
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The usefulness of plasma
ribonuclease
assays was studied in (i) patients with possible protein deficiency, (ii) patients with
myelomatosis
, (iii) patients with carcinoma of the breast. In each group, the major factor associated with elevation of plasma
ribonuclease
was impairment of renal function. The assay was therefore of little value in the assessment of patients with
myelomatosis
or carcinoma of the breast. However, in the patients with possible protein deficiency and normal renal function, an elevation of plasma
ribonuclease
is, in general, associated with a decrease in serum albumin, transferrin and cholinesterase. Plasma
ribonuclease
may therefore be a useful parameter in the assessment of protein nutritional status.
...
PMID:An assessment of the clinical usefulness of plasma ribonuclease assays. 97 78
Infusion of cycloheximide i.v., an antibiotic known to inhibit synthesis of protein, at a rate of 0.2 mg/kg/hr, reliably caused lysis of fever in 15 chronically febrile patients with Hodgkin's disease who did not have detectable bacterial, fungal, or viral infection. Antipyretic effects were also seen in some patients with reticulum cell sarcoma, lymphosarcoma, acute leukemia, histiocytic medullary reticulosis,
plasma cell myeloma
, carcinoma of the lung, and carcinoma of the cervix. The drug failed to produce defervescence in four patients with normal granulocyte reserves, who were febrile due to bacterial infection. When infused at a rate of 0.2 mg/kg/hr, the drug apparently caused an acute alteration of protein metabolism in man in that plasma amino acid nitrogen rose acutely while plasma levels of muramidase and
ribonuclease
fell during the period of the infusion. The data suggest that continuing synthesis of protein may be involved in nonbacterial fever of neoplastic disease. Mammalian granulocytes and monocytes are known to elaborate a pyrogenic protein following appropriate stimulation; it is suggested that in some types of neoplastic disease, particularly Hodgkin's disease, tumor cells may produce and release a pyrogenic protein and that drug-induced inhibition of its synthesis is responsible for the observed lysis of fever.
...
PMID:Antipyretic effect of cycloheximide, and inhibitor of protein synthesis, in patients with Hodgkin's disease or other malignant neoplasms. 109 49
The major form of methionine tRNA operational in the elongation of protein synthesis in mouse
myeloma
cells was purufied from these cells after they had been cultured in the presence of [32P]-phosphate. This [32P]tRNA4-Met species was then digested with T1
RNase
or
pancreatic RNase
so as to obtain both complete and partial
RNase
digestion products. The nucleotide sequences of these fragments were analysed to enable the derivation of the complete primary structure of this tRNA. tRNA4-Met of mouse
myeloma
cells is 76 nucleotides in length and contains 15 modified nucleotides. It is the only tRNA yet sequenced which has been found to possess the minor nucleoside 2-methylguanosine (m2G) within the amino acid (a) stem, and also to have an anticodon (c) stem of only 4 and not 5 base-pairs. The loop IV sequence of eukaryotic initiator methionine tRNA (tRNAf-Met) species, -A-U-C-G-m1A-A-A-, IS NOT FOUND IN TRNA4-Met and is therefore absent from at least one of the methionine tRNAs functioning in polypeptide elongation in mammalian cells. This is consistent with the suggested importance of this loop structure in the initiator function of tRNAf-Met in eukaryotic organisms. Three distinct regions of the tRNA cloverleaf, the (b) stem, the anticodon loop (loop II), and loop III, are substantially conserved in structure between tRNAf-Met and tRNA4-Met of mouse
myeloma
cells. These regions of the structures of mammalian methionine tRNAs probably do not determine whether a certain tRNA-Met will function in the initiation or elongation of protein synthesis, although they might be important in tRNA-Met recognition if the different cytoplasmic tRNA-Met species of mammalian cells are aminoacylated by a single activating enzyme.
...
PMID:The nucleotide sequence of a methionine tRNA which functions in protein elongation in mouse myeloma cells. 116 34
Nuclei of MPC 11 mouse
myeloma
cells contain several species of small RNAs related to those found in other mammalian cells. These include U1 RNA, about 190 nucleotides in length and U2 RNA, about 170 nucleotides long. The 5'-termini of 32P-labelled U1 and U2 RNAs have been investigated by a fingerprinting technique involving digestion with T2-
ribonuclease
. The RNAs were found to have modified 5'-terminal structures of the form m3G(5')ppp (5')AmpUmpAp for U1 RNA and m3G(5')ppp(5')AmpUmpCmpCp for U2 RNA, where m3G is N2, N27-trimethyl guanosine and Am and Um are 2'-O-methyl nucleosides. These 5'-terminal sequences are the same as those proposed for rat hepatoma U1 and U2 RNAs (Ro-Choi et al., Fed. Proc. 33, 1548, 1974) but with triphosphate rather than diphosphate links.
...
PMID:Modified 5'-termini in small nuclear RNAs of mouse myeloma cells. 121 81
BALB/c mice with the plasmacytoma MOPC 104E producing monoclonal IgM-lambda with antibody activity to alpha-1,3 dextran were found to have B lymphocytes with surface immunoglobulins with the immunochemical characteristics of 104E IgM capable of binding alpha-1,3 dextran. RNA extracted from this plasmacytoma induced the synthesis of such surface immunoglobulins on normal B lymphocytes in vitro and in vivo. Injection of 200 mug of MOPC 104E RNA into normal mice 72 hr prior to the administration of the antigen kept the immune response to dextran-S intact, but suppressed that to other antigens, such as DNP-Ficoll and LPS, T cell-independent antigens, and SRBC and BSA which are T cell-dependent. The effect of the RNA was abolished by
RNase
but not by pronase and DNase. RNA extracted from LPC-1 tumour (gamma2a-k without known antibody activity) significantly suppressed the immune response to dextran-S and to other antigens in normal mice. Thus, opposite effects of MOPC 104E RNA on the response to specific and non-specific antigens strengthen the hypothesis that the immune deficiency in plasmacytoma bearing mice is due to the conversion of normal surface immunoglobulin of a population of B lymphocytes to the idiotype of the respective
myeloma
globulin.
...
PMID:Surface immunoglobulins of lymphocytes in plasmacytoma. V. The effect of RNA-rich extract from mouse plasmacytoma MOPC 104E on the immune response. 127 83
We sought to determine the cis-acting elements responsible for the pattern of tissue specific expression of the mouse alpha 2(I) collagen gene. Using an
RNase
protection assay we first verified that expression of the alpha 2(I) collagen gene is mainly confined to tendons, bone, and skin in mice. Both transgenic mice and DNA transfection of tissue culture cells were used as experimental approaches. Transgenic mice lines were generated harboring chloramphenicol acetyltransferase (CAT) chimeric genes that contained either (a) 2000 base pairs (bp) of 5'-flanking sequences of the mouse alpha 2(I) collagen gene plus additional sequences between +418 and +1524 of the first intron of this gene or (b) the same promoter sequences without intron sequences or (c) the 350-bp proximal promoter sequences. Transgenic mice containing both types of 2000-bp promoters showed a pattern of CAT expression that was tissue specific. The presence of sequences of the first intron in the transgene did not increase the level of promoter activity. Transgenic mice harboring the 350-bp alpha 2(I) collagen promoter also showed a pattern that was tissue-specific except that high level expression also occurred in the brain. This suggests that negative regulation is an important component of tissue-specific expression. In order to analyze the first 350 bases in detail, we performed transient expression experiments, using promoter fragments attached to the luciferase reporter gene. Fibroblasts, which show a high level expression of the endogenous alpha 2(I) collagen gene, and B cells, in which the gene is silent, were transfected with a series of deletions and substitution mutations within the proximal 350-bp promoter. These experiments were unable to define unique cell-specific cis-acting elements. However, when the sequence between -315 and -284 was tandemly repeated upstream of a minimal alpha 2(I) collagen promoter (-41 to +54), the activity of this construction was considerably higher in fibroblasts than in B cells when compared with the minimal promoter itself. In gel retardation assays, the levels of complexes that bind to this sequence were higher in fibroblast nuclear extracts than in
myeloma
nuclear extracts. Our results are consistent with the hypothesis that the -315 to -284 DNA sequence participates in the cell-specific control of the alpha 2(I) collagen gene in fibroblasts.
...
PMID:Tissue-specific expression of the mouse alpha 2(I) collagen promoter. Studies in transgenic mice and in tissue culture cells. 152 81
The ultrastructural localization of RNA in
myeloma
cells was studied by the
RNase
-gold method. Gold particles indicating the presence of RNA were observed in large numbers, particularly in the granular component of the nucleolus and periphery of the rough endoplasmic reticulum, but not in the Golgi area, mitochondria, intranuclear inclusion bodies, cytoplasmic inclusion bodies, dense bodies, or cisternae of the rough endoplasmic reticulum. In the nuclear chromatin and nucleolus, gold particles were more numerous as these structures were less mature. They were found in larger numbers also in the cytoplasm of immature cells. In plasma cells from patients with macroglobulinemia, gold particles were fewer than in
myeloma
cells of
multiple myeloma
, but there was no difference in their distribution pattern.
...
PMID:Fine structural localization of RNA in myeloma cells detected by the enzyme-gold method. 169 57
Recent evidence suggests that tumour necrosis factor alpha (TNF) is an autocrine growth factor for the chronic B-cell malignancies hairy cell leukaemia (HCL) and some cases of B-chronic lymphocytic leukaemia (B-CLL). Incubation with TNF in vitro has been shown to increase viability, DNA synthesis and the expression of the protooncogenes myc, fos and jun in the tumour cells from these patients. TNF in vitro also increases expression of TNF-mRNA, suggesting the existence of an autocrine growth loop for TNF in these cells. Current experiments are compatible with the hypothesis that interferon alpha (IFN) interferes with this autocrine growth loop in HCL and B-CLL by stimulating degradation of messenger RNAs (mRNAs) for a number of cytokines including that of TNF. This RNA degradation may be mediated through induction of the enzyme 2,5 oligo-A synthetase with consequent increased synthesis of 2,5 oligo-A which is known to stimulate the activity of a latent
ribonuclease
capable of degrading cytokine mRNAs. Circulating tumour-derived TNF may also contribute to the pancytopenia in HCL and B-CLL. Whether cytokine autocrine growth loops are important in other B-cell malignancies, e.g.
myeloma
and non-Hodgkin's lymphoma, and subject to IFN-stimulated breakdown needs further study.
...
PMID:Possible mechanism of action of interferon alpha in chronic B-cell malignancies. 193 2
Seeking to optimize the immunocytochemical assay of P-glycoprotein, a 170-kilodalton (P-170) molecule associated with multidrug resistance, we experimented with a variety of antibodies (JSB-1, C219, and MRK-16), fixation conditions, and titers using both human
myeloma
cell lines and clinical
myeloma
specimens. Under optimized conditions, using all three antibodies and the cell lines as standards and controls, the ICC method proved sensitive, specific, reliable, rapid, and within the realm of everyday hospital laboratory expertise. The 3 anti-P-glycoprotein antibodies revealed different reactivities with P-170. Both C219 and JSB1 were optimized by fixation in cold acetone. With MRK-16 optimal results were obtained on unfixed or formalin fixed specimens. Under optimal fixation and titering conditions, low level (DOX 4) detection was possible. Given that the three antibodies differ in reactivity and recognize different P-170 epitopes, it follows that using the antibodies in a small panel is a useful strategy in increasing the likelihood of detecting true P-glycoprotein expression by the immunocytochemical method. In dilution experiments, the immunocytochemical method was as sensitive as
RNase
protection assay and more sensitive than Western blot detection. Immunocytochemistry coupled to computer-assisted single-cell densitometry, showed a strong correlation (R = 0.98) between cellular P-170 density and in vitro resistance to doxorubicin. Multidrug-resistant specific probes for RNA expression and Western blot assays confirmed the specificity of P-170 expression in both cell lines and clinical samples. Thus, a small panel of antibodies, under optimized immunocytochemical conditions, appears to have potential as a rapid, sensitive, clinically useful assay for multidrug resistance in
myeloma
.
...
PMID:Optimization of immunocytochemical P-glycoprotein assessment in multidrug-resistant plasma cell myeloma using three antibodies. 197 62
When immunoglobulin (Ig)-producing B cells are fused with fibroblastic cells, expression of Igs is suppressed by a mechanism that selectively abolishes transcription of Ig genes. The suppression is also maintained in proliferating hybrids. We have used gene transfer followed by cell fusion to study this phenomenon further. Here we report that expression of a rearranged Ig heavy chain gene, stably integrated into a
myeloma
genome, is completely suppressed upon fusion with fibroblasts by a mechanism that is equally active on the endogenous
myeloma
lambda light chain gene. To define regulatory sequences within the Ig transcriptional unit that are involved in this down-regulation, we examined the transcriptional contributions of the IgH chain gene enhancer and the kappa light chain gene promoter individually by linking them to a heterologous reporter gene. Mouse
myeloma
cells were stably transformed with such test constructs and subsequently fused with mouse fibroblasts. To avoid any significant loss of chromosomes, hybrid cells were isolated shortly after fusion by fluorescence-activated cell sorting, and proliferating hybrids were harvested within 2-3 weeks. On the basis of
RNase
protection mapping of cytoplasmic RNA, and of nuclear run-on assays we showed that both the kappa light chain promoter and the IgH chain enhancer contain regulatory information that is made redundant or is suppressed in the hybrid environment.
...
PMID:Both immunoglobulin promoter and enhancer sequences are targets for suppression in myeloma-fibroblast hybrid cells. 314 Nov 46
<< Previous
1
2
3
4
5
Next >>