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)

Recent studies have indicated a close relationship between inactivation of tumor suppressor genes (TSGs) and disease progression. The genes encoding the cyclin-dependent kinase inhibitors p16INK4A and p15INK4B are potent TSGs, and correlations between their inactivation and disease progression have also been reported in various malignancies. In this study, we analyzed the methylation status of p16INK4A and p15INK4B gene promoters in plasma cell dyscrasias (PCDs) by methylation-specific PCR (MSP). In analyses using DNAs extracted from bone marrow mononuclear cells (BM-MNCs), patients with multiple myeloma (MM) showed frequent hypermethylation of the p16INK4A gene (15/37, 41%), whereas p15INK4B gene methylation was not so frequent (5/37, 14%). Many patients whose BM-MNC showed dense methylation of the p16INK4A gene had extramedullary plasmacytoma (extra-PC), and all available extra-PC samples showed alterations of the p16INK4A gene (4; dense methylation, 1; homozygous deletion). In contrast to MM, hypermethylation of the p16INK4A gene was significantly infrequent in indolent PCDs (2/22, 9%, P= 0.0055). The infrequency in indolent PCDs was also confirmed by analyses using DNAs extracted from BM smears (1/29, 3%). It is possible that hypermethylation of the p16INK4A gene promoter contributes to progression to aggressive MM from indolent PCD, especially to extra-PC development.
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PMID:Hypermethylation of p16INK4A gene promoter during the progression of plasma cell dyscrasia. 1124 84

We have constructed NS0 myeloma cell lines that inducibly express the p21CIP1 cyclin dependent kinase inhibitor, using the Lacswitch system. Ectopic p21(CIP1) protein expression was rapidly induced within 12 h of addition of IPTG, causing G1-phase arrest and almost complete inhibition of cell proliferation. The production of a chimeric IgG4 antibody, expressed constitutively from an independent promoter, was found to be significantly increased by more than 4-fold in p21CIP1-arrested cells. This study demonstrates for the first time the successful construction of anchorage-independent and proliferation-controlled NS0 cell lines with enhanced secreted chimeric antibody production independent of the inducible promoter activity used to achieve cytostasis.
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PMID:Regulation of cell cycle and productivity in NS0 cells by the over-expression of p21CIP1. 1174 68

The coexistence of multiple myeloma (MM) and mycosis fungoides (MF), and hence of both B- and T-cell neoplastic clones, is a rare event. We describe a case of plaque-stage MF associated with IgG lambda MM. The clinical onset of MF preceded that of MM, supporting the hypothesis that MF predisposed to the development of the B-cell proliferative disorder. The skin tumor cells were found to originate from CD4(+) T-lymphocytes, characterized by a V beta 8 receptor and no proviral human T-lymphotropic virus (HTLV)-I monoclonal integration. They also displayed a polarized Th1-type cytokine profile containing mRNAs for interleukin (IL)-2, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-beta, but not for IL-4, IL-5, or IL-10. The CD8(+)/CD57(+) suppressor-cytotoxic subpopulation was significantly increased in the peripheral blood and was associated with MM progression. Expression of p16INK4A, a gene from the INK family that inhibits cyclin-dependent kinases and regulates the cell cycle, was lacking in MF cells and bone marrow (BM) plasma cells. The p16INK4A gene was silenced by hypermethylation, suggesting that it plays a role in the early phase of the pathogenesis of both diseases. Thus, a lymphoid precursor cell presumably contains aberrations that induce the development of both clonal diseases in a multistep process.
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PMID:Multiple myeloma and mycosis fungoides in the same patient: clinical, immunologic, and molecular studies. 1210 63

The retinoblastoma protein (pRb), p16(INK4A), D-type cyclins, and their partners cyclin-dependent kinase (CDK) 4 and 6 constitute a G(1) regulatory pathway commonly targeted in tumorigenesis. Several malignancies show a reciprocal correlation between genetic alterations of single members of the pRb pathway. Therefore, we determined the frequency of Rb deletions and cyclin D1 alterations by fluorescence in situ hybridization as well as 5' CpG island hypermethylation of the p16(INK4A)gene using methylation-specific polymerase chain reaction in bone marrow mononuclear cells from 82 individuals with plasma cell disorders. Alterations in at least one of the components of the pathway were found in 75%. Cyclin D1 translocations or amplifications were detected in 14/82 (17.1%), Rb deletions at 13q14 in 23/82 (28%) of the cases, including three (3.6%) homozygous deletions. p16(INK4A) was hypermethylated in 33/57 (57.9%) of the samples. Further analysis revealed a highly significant correlation between cyclin D1 alterations and extramedullar or leukemic myeloma manifestations (P = 0.014; Fisher's test). Whereas Rb deletions seemed to occur alternatively to cyclin D1 alterations, no reciprocal correlation was found between p16(INK4A) hypermethylations and cyclin D1 or Rb locus aberrations. Cyclin D1 locus alterations and Rb deletions were associated with a significantly worse prognosis whereas p16(INK4A) hypermethylation had no impact on survival. We conclude that cyclin D1 and Rb aberrations seem to occur as alternative events in plasma cell malignancies and contribute to clinical course and prognosis. In contrast, although p16(INK4A) hypermethylation is frequent, inactivation of p16(INK4A) seems not to be involved in the pathogenesis of plasma cell disorders.
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PMID:Alterations of the cyclin D1/pRb/p16(INK4A) pathway in multiple myeloma. 1220 Jul 2

To study the action, characteristics and expression of high methylation of p15(INK4B) and p16(INK4A) genes in multiple myeloma (MM), the sensitive methylation specific PCR method was employed to detect the hypermethylation of p15(INK4B) and p16(INK4A) in 24 patients with MM. Results showed that the methylation incidence of p15(INK4B) and p16(INK4A) genes were 70.8% (17/24) and 58.3% (14/24) in the MM patients, with the products of 148 bp and 150 bp fragments, respectively. The methylation of p15(INK4B) and p16(INK4A) genes were simultaneously happened in MM patients of plasmocytoma type with two cases at II phase and two cases at III phase. The simultaneous non-methylation of p15(INK4B) and p16(INK4A) genes were founded in five cases of MM patients, all of the tumor cells were of small plasmocyte type with mature differention. Conclusion suggested that there were high incidence of methylation of p15(INK4B) and p16(INK4A) genes in patients with MM. Hypermethylation can be detected in the early stage of disease, which was associated with its progress. It indicated a bad prognosis when methylation happended simultaneously in the two genes. Methylation of p15(INK4B) and p16(INK4A) genes may be related to the pathogeny of MM.
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PMID:[Detection of High Methylation of p15(INK4B) and p16(INK4A) Genes in Multiple Myeloma] 1257 64

The molecular basis for aggressive transformation of multiple myeloma (MM) and other cancers is not completely understood. Global gene expression profiling on highly purified malignant plasma cells from 351 newly diagnosed patients with MM treated with autologous stem cell transplantation revealed a statistically significant over-representation of chromosome 1 genes in a group of 70 genes whose expression was linked to poor outcome. In particular, over-expression of CKS1B, which maps to an amplicon at 1q21 in myeloma and regulates SCF(Skp2)-mediated ubquitination and proteolysis of the cyclin dependent kinase inhibitor p27Kip1 was significantly over-expressed in patients with poor survival. Interphase fluorescence in-situ hybridization revealed that CKS1B expression was strongly correlated with DNA copy number in a subset of 197 cases (P<0.0001) with both measurements. Validated in 224 patients lacking expression analysis, CKS1B gene amplification conferred a poor prognosis (P<0.0001) and was an independent predictor of outcome in multivariate analyses (P=0.002). CKS1B mRNA and protein expression were correlated and both were inversely correlated with p27(Kip1) protein levels. RNA interference of CKS1B messenger RNA in myeloma cell lines led to reduced CKS1B mRNA and protein, an accumulation of p27Kip1, and profound growth inhibition. Based on these data we conclude that over-expression of CKS1B, mainly due to gene amplification, imparts a poor prognosis in MM, possibly as a result of enhanced degradation of p27Kip1.
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PMID:Amplification and overexpression of CKS1B at chromosome band 1q21 is associated with reduced levels of p27Kip1 and an aggressive clinical course in multiple myeloma. 1618 52

In the detection of DNA hypermethylation as a tumor-specific epigenetic change in blood mononuclear cell fraction in patients with lymphoid and hematopoetic disorders, circulating tumor cells originating from the lymph nodes or bone marrow can be identified. However, it is still not clear whether methylation in mononuclear cells is disease specific. In the present study, we investigated whether methylation of the inhibitor of cyclin-dependent kinase (INK) 4A/alternative reading frame (ARF) locus is present in a disease-specific manner in the blood mononuclear cell fraction of patients with lymphoma, multiple myeloma, or leukemia. To increase the sensitivity of detection, a two-step methylation-specific PCR approach was used to analyze the methylation status of the promoter/exon 1 regions of both p14ARF and p16INK4A genes. Our findings indicate that although INK4A/ARF locus methylation is present in mononuclear cells, this event is not disease-specific since normal subjects also display methylated DNA in their mononuclear cells. In 85.1% of the patients and in 89% of the controls, p16INK4A gene was methylated, while the methylation rates for the p14ARF gene was 32.6 and 36.5%, respectively. The presence of methylated CpG sites in DNA in samples from normal subjects was confirmed by bisulfite genomic sequencing. The difference in the methylation rate between p16INK4A and p14ARF genes among the patients was highly significant (p<0.001). Our results demonstrate that methylation of the INK4A/ARF locus is not a disease-specific molecular change in mononuclear cell fraction and that the p14ARF and p16INK4A genes are differentially methylated.
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PMID:Methylation of the INK4A/ARF locus in blood mononuclear cells. 1632 52

Aberrant DNA methylation is considered an important epigenetic mechanism for gene inactivation. Monoclonal gammopathy of undetermined significance (MGUS) is believed to be a precursor of multiple myeloma (MM). We have analyzed methylation status of p15 INK4B , p16 INK4A , ARF, SOCS-1, p27 KIP1 , RASSF1A, and TP73 genes in bone marrow DNA samples from 21 MGUS and 44 MM patients, in order to determine the role of aberrant promoter methylation as one of the steps involved in the progression of MGUS to MM. Methylation specific polymerase chain reaction assay followed by DNA sequencing of the resulting product was performed. SOCS-1 gene methylation was significantly more frequent in MM (52%) than in MGUS (14%; p=0,006). Methylation frequencies of TP73, ARF, p15 INK4B , p16 INK4A , and RASSF1A were comparable in MGUS: 33%, 29%, 29%, 5%, and 0%, to that observed in MM: 45%, 29%, 32%, 7%, and 2%. All patients lacked methylation at p27 KIP1 gene. In both entities, a concurrent methylation of p15 INK4B and TP73 was observed. The mean methylation index of MGUS was lower (0.16) than that of MM (0.24; p<0.05). Correlations with clinicopathologic characteristics showed a higher mean age in MGUS patients with SOCS-1 methylated (p<0.001); meanwhile in MM, methylation of p15 INK4B was more frequent in males (p=0.009) and IgG isotype (p=0.038). Our findings suggest methylation of TP73, ARF, p15 INK4B , and p16 INK4A as early events in the pathogenesis and development of plasma cell disorders; meanwhile, SOCS-1 methylation would be an important step in the clonal evolution from MGUS to MM.
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PMID:DNA methylation analysis of tumor suppressor genes in monoclonal gammopathy of undetermined significance. 1972 27

ANKHD1 is a multiple ankyrin repeat containing protein, highly expressed in cancers, such as acute leukemia. The present study was undertaken to determine the expression and functional significance of ANKHD1 in human Multiple Myeloma (MM). We found that ANKHD1 is highly expressed in MM patient cells and cell lines. In vitro, lentiviral mediated ANKHD1-shRNA inhibited proliferation and delayed S to G2M cell cycle progression in glucocorticoid resistant (U266) and sensitive (MM1S) MM cells. Further ANKHD1 silencing resulted in upregulation of cyclin dependent kinase inhibitor p21 irrespective of the p53 status of the MM cell lines. These data suggest that ANKHD1 might have a role in MM cell proliferation and cell cycle progression by regulating expression of p21.
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PMID:ANKHD1 regulates cell cycle progression and proliferation in multiple myeloma cells. 2314 81

Aberrant DNA hypermethylation contributes to myelomagenesis by silencing tumor-suppressor genes. Recently, a few reports have suggested that a novel class of small non-coding RNAs, called Piwi-interacting RNAs (piRNAs), may be involved in the epigenetic regulation of cancer. In this study, for the first time we provided evidence that the expression of piRNA-823 was upregulated in multiple myeloma (MM) patients and cell lines, and positively correlated with clinical stage. Silencing piRNA-823 in MM cells induced deregulation of cell cycle regulators and apoptosis-related proteins expression, accompanied by inhibition of tumorigenicity in vitro and in vivo. Moreover, piRNA-823 was directly relevant to de novo DNA methyltransferases, DNMT3A and 3B, in primary CD138(+) MM cells. The inhibited expression of piRNA-823 in MM cells resulted in marked reduction of DNMT3A and 3B at both mRNA and protein levels, which in turn led to decrease in global DNA methylation and reexpression of methylation-silenced tumor suppressor, p16(INK4A). In addition, piRNA-823 abrogation in MM cells induced reduction of vascular endothelial growth factor secretion, with consequent decreased proangiogenic activity. Altogether, these data support an oncogenic role of piRNA-823 in the biology of MM, providing a rational for the development of piRNA-targeted therapeutic strategies in MM.
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PMID:piRNA-823 contributes to tumorigenesis by regulating de novo DNA methylation and angiogenesis in multiple myeloma. 2473 95


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