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)

SOCS1 and SHP1 negatively regulate the Janus kinase/signal transducer and activator of transcription (Jak/STAT) signaling pathway. The role of promoter hypermethylation leading to epigenetic inactivation of SOCS1 and SHP1 in myeloma was investigated. The methylation-specific polymerase chain reaction (MSP) was used to define SOCS1 and SHP1 methylation in 34 diagnostic myeloma samples. For SOCS1, MSP primers 3' to the translation start site were unreliable and gave positive results in normal controls. However, primers in the 5' promoter region were specific, although no myeloma samples showed methylation. For SHP1, 27 of 34 (79.4%) myeloma samples showed SHP1 hypermethylation. The biologic significance of SHP1 methylation was investigated in the U266 human myeloma line. U266 contained completely methylated SHP1. Furthermore, there was constitutive STAT3 phosphorylation. Treatment with 5-azacytidine led to progressive demethylation of SHP1 on days 2 to 5, with consequent increasing reexpression of SHP1 as shown by reverse transcription-polymerase chain reaction (RT-PCR). Concomitant with increasing SHP1, a parallel down-regulation of phosphorylated STAT3 occurred, so that by day 5 phosphorylated STAT3 was barely detectable. The overall survivals of patients with and without SHP1 methylation were similar. SHP1 methylation leading to epigenetic activation of the Jak/STAT pathway might have a tentative role in the pathogenesis of myeloma, which should be further confirmed by functional studies in primary myeloma samples.
 ...
PMID:SOCS1 and SHP1 hypermethylation in multiple myeloma: implications for epigenetic activation of the Jak/STAT pathway. 1497 49

The perturbations of the cytokine signaling pathway play an important role in lymphoid/hematopoietic tumors. Aberrant promoter methylation is the major mechanism of gene silencing in tumors. We examined 150 lymphoid/hematopoietic tumors or potential premalignant specimens, 55 control specimens and 12 EBV-transformed B lymphoblastoid cultures and 10 lymphoma/leukemia (L/L) or multiple myeloma (MM) cell lines for the methylation (and, in cell lines, of the expression status) of three genes involved in the cytokine signaling pathway. The genes were: SHP1, a protein tyrosine phosphatase; SYK, a protein kinase; and SOCS1, a suppressor of cytokine signaling. Our major findings were: (1) one or more of the three genes was frequently methylated in L/L and MM cell lines and there was good concordance (90-100%) between methylation and loss of gene expression; (2) treatment of L/L cell lines with a demethylating agent resulted in re-expression of SHP1 protein and downregulation of phosphorylated STAT3 in L/L cell lines; (3) all 55 control specimens and the lymphoblastoid cultures were negative for methylation of the three genes; (4) non-Hodgkin's lymphomas (100%), and leukemias (94%) had almost universal methylation of SHP1 and relatively less frequent (<30%) methylation of SOCS1 and SYK; (5) MM and monoclonal gammopathy of unknown significance (MGUS) had infrequent methylation of SHP1 (<20%), and occasional methylation of SOCS1 and SYK; and (6) comparable methylation frequencies for SOCS1 were observed in MM and MGUS, suggesting that SOCS1 methylation is an early event in MM pathogenesis. At least one gene was methylated in 119 of 130 (93%) of the malignant and 12 of 20 (60%) of the MGUS samples. Our findings demonstrate that the perturbations of cytokine signaling via silencing of these three genes are almost universal in lymphoid/hematopoietic tumors but the patterns of gene methylated for L/L and plasma cell dyscrasias are different.
 ...
PMID:Differential methylation of genes that regulate cytokine signaling in lymphoid and hematopoietic tumors. 1558 Mar 14

Malignant transformation is a multistep process that may involve dysregulation of oncogenes and tumour suppressor genes, and monoclonal gammopathy of undetermined significance (MGUS) is believed to be a precursor of multiple myeloma. To investigate whether aberrant promoter methylation might be involved in the evolution of MGUS to multiple myeloma, we examined the p16, protein tyrosine phosphatase, non-receptor type 6 (SHP1), death-associated protein (DAP) kinase, E-cadherin and oestrogen receptor genes, most being tumour suppressor genes, by methylation-specific polymerase chain reaction. In 32 cases of multiple myeloma and 19 cases of MGUS, significantly more frequent methylation of p16 (p = 0.001), SHP1 (p< or =0.001) and E-cadherin (p< or =0.001) genes was found in multiple myeloma than in MGUS. Methylation of DAP kinase and oestrogen receptor genes was comparable in multiple myeloma and MGUS. In conclusion, methylation of p16, SHP1 and E-cadherin genes might be involved in the progression of MGUS to multiple myeloma.
 ...
PMID:Aberrant gene methylation implicated in the progression of monoclonal gammopathy of undetermined significance to multiple myeloma. 1721 58

Multiple myeloma (MM) is an incurable plasma cell neoplasm. Pathogenesis involves upregulation of D-type cyclins and activation of oncogenes, but little is known about the role of tumor suppressor genes. Gene hypermethylation is an alternative mechanism of tumor suppressor gene inactivation. Various approaches have been used to elucidate the role of gene hypermethylation in MM, including a candidate gene approach, microarray approach for genes upregulated by hypomethylating agents, and a cancer pathway approach, which enables a comprehensive picture of the involvement of multiple tumor suppressor genes in MM. Based on the cancer pathway approach, the following data on the involvement of cell cycle control, intrinsic tumor suppressor, and cell signaling were derived. First, among the INK4 and CIP/KIP families of cyclin-dependent kinase inhibitors, only CDKN2B and CDKN2A are frequently hypermethylated. Second, methylation of SHP1 and soluble Wnt inhibitors is associated with constitutive activation of JAK/STAT and Wnt signaling. Importantly, downregulation of the signaling pathways can be restored by demethylation and re-expression of SHP1 and soluble Wnt inhibitors, which is potentially important therapeutically. Third, of the tumor suppressor genes involved in the DAPK/P14/HDM2/P53/Apaf-1 pathway, only DAPK is frequently methylated, which appeared to be an adverse prognostic factor to survival. Lastly, apart from being implicated in the progression from monoclonal gammopathy of unknown significance to MM, aberrant gene promoter methylation might also account for late disease progression in MM. Future studies are needed to delineate the biologic consequence of gene hypermethylation, the prognostic effect of gene methylation, and the possibility of hypomethylation therapy.
Clin Lymphoma Myeloma 2008 Dec
PMID:Gene hypermethylation in multiple myeloma: lessons from a cancer pathway approach. 1906 97

The major goal of cancer drug discovery is to find an agent that is safe and affordable, yet effective against cancer. Here we show that morin (3,5,7,2',4'-pentahydroxyflavone) has potential against cancer cells through suppression of the signal transducer and activator of transcription 3 (STAT3) pathway, which is closely linked to the transformation, survival, proliferation, and metastasis of cancer. We found that morin completely suppressed inducible and constitutively activated STAT3 and blocked the nuclear translocation of STAT3 and its DNA binding in multiple myeloma and head and neck squamous carcinoma cells. Morin inhibited activated Src, JAK-1, and JAK-2, all of which are linked to STAT3 activation, while up-regulating a protein inhibitor of activated STAT3, PIAS3. Pervanadate reversed the effects of morin on STAT3 phosphorylation, indicating the role of a protein tyrosine phosphatase. Furthermore, morin induced SHP1 expression at both the mRNA and protein levels, and silencing of SHP1 abrogated the effect of morin on STAT3 phosphorylation, indicating that morin mediates its effects on STAT3 through SHP1. Suppression of STAT3 correlated with the down-regulation of various gene products linked to tumor survival, proliferation, and angiogenesis and led to sensitization of tumor cells to thalidomide and bortezomib. Comparing the activities of morin with those of four structurally related flavonols demonstrated the importance of hydroxyl groups in the B ring in inhibiting STAT3 activation. These findings suggest that morin suppresses the STAT3 pathway, leading to the down-regulation of STAT3-dependent gene expression and chemosensitization of tumor cells.
 ...
PMID:Morin inhibits STAT3 tyrosine 705 phosphorylation in tumor cells through activation of protein tyrosine phosphatase SHP1. 2327 49

Spatial and subclonal genetic heterogeneity in multiple myeloma (MM) have been demonstrated by sequencing of plasma cells from multi-focal regions, but studies of spatial epigenetic heterogeneity are scanty. Herein, promoter methylation status of genes implicated in disease progression (CDKN2A and SHP1) and marrow escape (CDH1, CD56, and CXCR4) was studied in two patients with multi-focal extramedullary relapses. Patient 1 developed simultaneous chest wall and duodenal plasmacytoma at relapse. While SHP1 and CDKN2A were hypermethylated in both plasmacytomas, CDH1 hypermethylation was detected only in the chest wall. In patient 2, SHP1 methylation was found in the extradural plasmacytoma but not bone marrow (BM) at diagnosis, and the circulating PCs but not the BM at relapse. As the clonality, based on sequence of the complementarity-determining region 3 (CDR3) of the immunoglobulin gene, was conserved in plasma cells at diagnosis and relapse, differential methylation of CDH1 in patient 1 and SHP1 in patient 2 was an illustration of spatial epigenetic heterogeneity. Furthermore, subclonal epigenetic heterogeneity was identified by the presence of subclonal SHP1 promoter methylation within the chest wall plasmacytoma of patient 1. In summary, our data showed distinct promoter methylation profile of plasma cells from multiple regions. This is the first report of spatial epigenetic heterogeneity in MM.
 ...
PMID:Distinct promoter methylation profile reveals spatial epigenetic heterogeneity in 2 myeloma patients with multifocal extramedullary relapses. 3057 45