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

Chromosome 14q +, which represents a chromosomal rearrangement involving the immunoglobulin heavy chain gene (IgH) locus, is a genetic hallmark of human multiple myeloma (MM). Here, we report the identification of (14;20)(q32;q11) chromosomal translocations found in MM cells. Double color fluorescence in situ hybridization analyses pinpointed the breakpoints at the 20q11 locus in two MM cell lines within a length of at most 680 kb between the KIAA0823 and MAFB gene loci. Among the transcribed sequences in the vicinity of the breakpoints, an ectopic expression of the MAFB gene, which is located at 450 - 680 kb telomeric to one of the breakpoints and encodes a member of the MAF family basic region / leucine zipper transcription factor, was demonstrated to be associated with t(14;20). This finding, together with that of a previous study describing its transforming activity, suggests that the MAFB gene may be one of the targets deregulated by regulatory elements of the IgH gene as a result of t(14;20).
 ...
PMID:Ectopic expression of MAFB gene in human myeloma cells carrying (14;20)(q32;q11) chromosomal translocations. 1142 52

Chromosomal translocations involving the immunoglobulin heavy chain gene (IgH) and nonrandom protooncogene loci are the hallmark of genetic alterations found not only in multiple myeloma (MM), but also in premalignant stages of MM, including monoclonal gammopathy of undetermined significance (MGUS) and smoldering myeloma (SMM). We studied the frequency of IgH (14q32) rearrangements and their partner chromosomes in 16 Japanese patients with MGUS (13 cases), and SMM (3 cases) by means of interphase double-color fluorescence in situ hybridization (DCFISH) applied to purified plasma cells and using CD138-bead selection. IgH rearrangement was recognized in nine of the patients (56.3%). Protooncogene loci juxtaposed to IgH were identified in seven cases including CCND1 (11q13) in six cases and FGFR3 (4p16) in one. Four out of the six t(11;14)-positive cases showed nuclear staining of the cyclin D1 protein, whereas none of the seven t(11;14)-negative cases did. Moreover, neither MUM1(6p25)-IgH nor MAFB(20q11)-IgH fusion signals were observed. This suggests to us that cyclin D1 deregulation due to the presence of t(11;14) is involved in the early development of plasma cell neoplasms, and that this event alone is not enough for the development of symptomatic myeloma.
 ...
PMID:Frequent occurrence of CCND1 deregulation in patients with early stages of plasma cell dyscrasia. 1282 3

Chromosomal translocations of the immunoglobulin heavy chain (IgH) gene region at 14q32 are regularly involved in B lymphoid malignancies; they may initiate transformation either by deregulation of existing (proto) oncogenes or creation of new hybrid genes with transforming properties. Previously, we reported a reciprocal novel translocation, t(14;20)(q32;q12), found in the myeloma cell line UM3. In this cell line, the t(14;20) is the only translocation involving the IgH locus. Using double colour immunofluorescence in situ hybridization, the t(14;20) was also found in the diagnostic bone marrow sample, excluding a possible in vitro artefact. We also have found this recurrent t(14;20) in four other cell lines and in additional patient material. We cloned the regions containing the breakpoints in the der(14) and der(20) chromosomes from UM3, and analysed ectopic mRNA expression of genes in the breakpoint regions of both derivative chromosomes. Ectopic gene expression was observed for the transcription factor MAFB in der(14). The breakpoint scatter in the five cell lines with a t(14;20)--all expressing MAFB--is comprised within a region of 0.8 Mb. Provisional data indicate that this t(14;20) is associated with an adverse prognosis. Aberrant expression of MAFB may be involved in the oncogenic transformation of myeloma cells that harbour the t(14;20).
 ...
PMID:The recurrent translocation t(14;20)(q32;q12) in multiple myeloma results in aberrant expression of MAFB: a molecular and genetic analysis of the chromosomal breakpoint. 1525 7

Chromosomal translocations involving the immunoglobulin heavy chain (IGH) locus and various partner loci frequently are associated with multiple myeloma (MM). We investigated the expression profiles of the FGFR3/MMSET, CCND1, CCND3, MAF, and MAFB genes, which are involved in t(4;14)(p16.3;q32), t(11;14)(q13;q32), t(6;14)(p21;q32), t(14;16)(q32;q23), and t(14;20)(q32;q12), respectively, in purified plasma cell populations from 39 MMs and six plasma cell leukemias (PCL) by DNA microarray analysis and compared the results with the presence of translocations as assessed by dual-color FISH or RT-PCR. A t(4;14) was found in 6 MMs, t(11;14) in 9 MMs and 1 PCL, t(6;14) in 1 MM, t(14;16) in 2 MMs and 1 PCL, and t(14;20) in 1 PCL. In all cases, the translocations were associated with the spiked expression of target genes. Furthermore, gene expression profiling enabled the identification of putative translocations causing dysregulation of CCND1 (1 MM and 1 PCL) and MAFB (1 MM and 1 PCL) without any apparent involvement of immunoglobulin loci. Notably, all of the translocations were mutually exclusive. Markedly increased MMSET expression was found in 1 MM showing associated FGFR3 and MMSET signals on an unidentified chromosome. Our data suggest the importance of using combined molecular cytogenetic and gene expression approaches to detect genetic aberrations in MM.
 ...
PMID:Characterization of oncogene dysregulation in multiple myeloma by combined FISH and DNA microarray analyses. 1554 17

Multiple myeloma (MM) is the most common form of plasma cell dyscrasia, characterized by a marked heterogeneity of genetic lesions and clinical course. It may develop from a premalignant condition (monoclonal gammopathy of undetermined significance, MGUS) or progress from intramedullary to extramedullary forms (plasma cell leukemia, PCL). To provide insights into the molecular characterization of plasma cell dyscrasias and to investigate the contribution of specific genetic lesions to the biological and clinical heterogeneity of MM, we analysed the gene expression profiles of plasma cells isolated from seven MGUS, 39 MM and six PCL patients by means of DNA microarrays. MMs resulted highly heterogeneous at transcriptional level, whereas the differential expression of genes mainly involved in DNA metabolism and proliferation distinguished MGUS from PCLs and the majority of MM cases. The clustering of MM patients was mainly driven by the presence of the most recurrent translocations involving the immunoglobulin heavy-chain locus. Distinct gene expression patterns have been found to be associated with different lesions: the overexpression of CCND2 and genes involved in cell adhesion pathways was observed in cases with deregulated MAF and MAFB, whereas genes upregulated in cases with the t(4;14) showed apoptosis-related functions. The peculiar finding in patients with the t(11;14) was the downregulation of the alpha-subunit of the IL-6 receptor. In addition, we identified a set of cancer germline antigens specifically expressed in a subgroup of MM patients characterized by an aggressive clinical evolution, a finding that could have implications for patient classification and immunotherapy.
 ...
PMID:Gene expression profiling of plasma cell dyscrasias reveals molecular patterns associated with distinct IGH translocations in multiple myeloma. 1573 37

Two oncogenic pathways have been hypothesized for multiple myeloma (MM) and premalignant monoclonal gammopathy of undetermined significance (MGUS) tumors: a nonhyperdiploid pathway associated with a high prevalence of IgH translocations and a hyperdiploid pathway associated with multiple trisomies of 8 chromosomes. Cyclin D1, D2, or D3 expression appears to be increased and/or dysregulated in virtually all MM tumors despite their low proliferative capacity. Translocations can directly dysregulate CCND1 (11q13) or CCND3 (6p21), or MAF (16q23) or MAFB (20q11) transcription factors that target CCND2. Biallelic dysregulation of CCND1 occurs in nearly 40% of tumors, most of which are hyperdiploid. Other tumors express increased CCND2, either with or without a t(4;14) translocation. Using gene expression profiling to identify 5 recurrent translocations, specific trisomies, and expression of cyclin D genes, MM tumors can be divided into 8 TC (translocation/cyclin D) groups (11q13, 6p21, 4p16, maf, D1, D1+D2, D2, and none) that appear to be defined by early, and perhaps initiating, oncogenic events. However, despite subsequent progression events, these groups have differing gene expression profiles and also significant differences in the prevalence of bone disease, frequency at relapse, and progression to extramedullary tumor.
 ...
PMID:Cyclin D dysregulation: an early and unifying pathogenic event in multiple myeloma. 1575 96

ARK5, AMP-activated protein kinase (AMPK)-related protein kinase mediating Akt signals, is closely involved in tumor progression, and its stage-associated expression was observed in colorectal cancer. In this study, we found ARK5 expression in multiple myeloma cell lines expressing c-MAF and MAFB. In addition, gene expression profiling of 351 clinical specimens revealed ARK5 expression in primary myelomas expressing c-MAF and MAFB, suggesting that ARK5 may be a transcriptional target of the Large-MAF family. Sequence analysis of the ARK5 gene promoter revealed that it contains two putative MAF-recognition element (MARE) sequences. In support of this hypothesis, ARK5 was induced when an MAFB or c-MAF expression vector was introduced into non-ARK5-expressing colon cancer cells. Furthermore, ARK5 promoter activity was dramatically decreased by mutation or deletion of MARE sequences. Chromatin immunoprecipitation assays revealed an interaction between the Large-MAF family proteins and MARE sequences in the ARK5 promoter. Moreover, in ARK5 mRNA-expressing multiple myeloma lines, but not in ARK5-negative lines, insulin-like growth factor (IGF)-1 increased invasion activity. IGF-1-induced invasion was reproduced when ARK5 was overexpressed in Burkitt's lymphoma and plasmacytoma lines. Based on results, we conclude that ARK5 is a transcriptional target of the Large-MAF family through MARE sequence and that ARK5 may in part mediate the aggressive phenotype associated with c-MAF- and MAFB-expressing myelomas.
 ...
PMID:ARK5 is transcriptionally regulated by the Large-MAF family and mediates IGF-1-induced cell invasion in multiple myeloma: ARK5 as a new molecular determinant of malignant multiple myeloma. 1604 63

There appear to be two pathways involved in the pathogenesis of premalignant non-immunoglobulin M (IgM) monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM). Nearly half of tumors are nonhyperdiploid, and mostly have one of five recurrent IgH translocations: 16% 11q13 (CCN D1), 3% 6p21 (CCN D3), 5% 16q23 (MAF), 2% 20q12 (MAFB), and 15% 4p16 (FGFR3 and MMSET). The remaining hyperdiploid tumors have multiple trisomies involving chromosomes 3, 5, 7, 9, 11, 15, 19, and 21, and infrequently one of these five translocations. Although cyclin D1 is not expressed by healthy lymphoid cells, it is bi-allelically dysregulated in a majority of hyperdiploid tumors. Virtually all MM and MGUS tumors have dysregulated and/or increased expression of cyclin D1, D2, or D3, providing an apparent early, unifying event in pathogenesis. The patterns of translocations and cyclin D expression (TC) define a novel classification that includes eight groups: 11q; 6p; MAF; 4p; D1 (34%); D1+D2 (6%); D2 (17%); and none (2%). The hyperdiploid D1 group is virtually absent in extramedullary MM and MM cell lines, suggesting a particularly strong dependence on interaction with the bone marrow microenvironment. Despite shared progression events (RAS mutations, MYC dysregulation, p53 mutations, and additional disruption of the retinoblastoma pathway), the phenotypes of MGUS and MM tumors in the eight TC groups is determined mainly by early oncogenic events. Similar to acute lymphocytic leukemia, MM seems to include several diseases (groups) that have differences in early or initiating events, global gene expression patterns, bone marrow dependence, clinical features, prognosis, and response to therapy.
 ...
PMID:Molecular pathogenesis and a consequent classification of multiple myeloma. 1615 16

Multiple myeloma is a tumor of somatically mutated, isotype-switched plasma cells that accumulate in the bone marrow leading to bone destruction and bone marrow failure. The germinal center processes of somatic hypermutation and switch recombination are implicated in the development of recurrent immunoglobulin gene translocations in 40% of patients. These affect five loci: 11q13, 6p21, 4p16, 16q23 and 20q11, leading to dysregulation of CCND1, CCND2, FGFR3/MMSET, c-MAF and MAFB respectively. The remaining 60% of patients can be divided into four groups based on their expression of CCND1 and CCND2. The largest group (40%) ectopically express CCND1 bi-allelically and have hyperdiploidy with multiple trisomies of chromosomes 3, 5, 7, 9, 11, 15, 19 and 21. The translocation and cyclin D (TC) groups identify patients with different genetics, biology, clinical features, prognosis and response to therapy.
 ...
PMID:Early genetic events provide the basis for a clinical classification of multiple myeloma. 1630 2

To better define the molecular basis of multiple myeloma (MM), we performed unsupervised hierarchic clustering of mRNA expression profiles in CD138-enriched plasma cells from 414 newly diagnosed patients who went on to receive high-dose therapy and tandem stem cell transplants. Seven disease subtypes were validated that were strongly influenced by known genetic lesions, such as c-MAF- and MAFB-, CCND1- and CCND3-, and MMSET-activating translocations and hyperdiploidy. Indicative of the deregulation of common pathways by gene orthologs, common gene signatures were observed in cases with c-MAF and MAFB activation and CCND1 and CCND3 activation, the latter consisting of 2 subgroups, one characterized by expression of the early B-cell markers CD20 and PAX5. A low incidence of focal bone disease distinguished one and increased expression of proliferation-associated genes of another novel subgroup. Comprising varying fractions of each of the other 6 subgroups, the proliferation subgroup dominated at relapse, suggesting that this signature is linked to disease progression. Proliferation and MMSET-spike groups were characterized by significant overexpression of genes mapping to chromosome 1q, and both exhibited a poor prognosis relative to the other groups. A subset of cases with a predominating myeloid gene expression signature, excluded from the profiling analyses, had more favorable baseline characteristics and superior prognosis to those lacking this signature.
 ...
PMID:The molecular classification of multiple myeloma. 1672 3


1 2 3 4 Next >>