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 chromosomal abnormality der(9)t(1;9)(q11;q34) is a rare occurrence in patients with hematologic malignancies. As far as we know, only 3 cases of acute myeloid leukemia, 1 case of polycythemia vera, and 1 case of multiple myeloma with this derivative chromosome have been reported in the literature. Here we report the first case of der(9)t(1;9)(q11;q34) in a patient with chronic myelomonocytic leukemia (CMML). A 45-yr-old man was brought to our hospital for evaluation of pancytopenia and monocytosis. The patient's persistent monocytosis in peripheral blood and his bone marrow findings were consistent with the diagnosis of CMML. Chromosome study results repeatedly showed 46,XY,der(9)t(1;9)(q11;q34). In addition, the BCR/ABL fluorescent in situ hybridization (FISH) pattern of the interphase cells was interpreted as: "nuc ish(ABL, BCR) x 2[292/300]," consistent with the normal signal patterns found in 97% of the nuclei examined. For further evaluation, multi-color FISH (mFISH) analysis was performed and it showed the distinct unbalanced derivative chromosome der(9)t(1;9)(q11;q34) in 5 metaphase cells analyzed. Not only does this show an extraordinary type of trisomy 1q, but it reveals a rare recurrent case of der(9)t(1;9)(q11;q34) in patients with monocytic-lineage leukemia. Further studies are needed to evaluate the prognosis, survival, and treatment response of such patients with der(9)t(1;9)(q11;q34).
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PMID:Chronic myelomonocytic leukemia with der(9)t(1;9)(q11;q34) as a sole abnormality. 1966 17

The outlook for newly diagnosed patients with chronic myeloid leukemia (CML) in the imatinib era is excellent for most patients. However, imatinib failure is observed in around 25%-30% of patients. With the availability of second-line tyrosine kinase inhibitor therapy and/or allogeneic transplantation, many of these patients with imatinib failure can still achieve durable cytogenetic and molecular responses. Early evidence of imatinib resistance, when the biology of the emerging leukemia might still be relatively favorable, is the best time to switch to second-line therapy. Close cytogenetic and molecular monitoring will facilitate early intervention in appropriate cases. However, caution should be used when interpreting minimal residual disease data, and the danger of inappropriate changes in therapy based on assay fluctuations should be recognized. A significant increase in the level of BCR-ABL to a level > 0.1% on the international scale (major molecular response) should prompt a repeat BCR-ABL assay, a mutation screen, and possibly marrow cytogenetics. What constitutes a significant increase depends on the laboratory-specific measurement reliability. The possibilities of poor compliance or drug interactions should be considered. If the repeat BCR-ABL assay, fluorescence in situ hybridization assay, or cytogenetics confirms loss of complete cytogenetic response or if a mutation is identified, a dose increase or a switch in therapy to a second-line kinase inhibitor might be indicated. At least until complete molecular response is achieved, regular real-time polymerase chain reaction monitoring reinforces the fact that leukemia is still present and that compliance is a challenge that requires ongoing vigilance from the patient and the clinician.
Clin Lymphoma Myeloma 2009
PMID:Measuring minimal residual disease in chronic myeloid leukemia: fluorescence in situ hybridization and polymerase chain reaction. 1977 51

The discovery of the JAK2V617F mutation followed by the discovery of JAK2 exon 12 and MPLW515 mutations has completely modified the understanding, diagnosis, and management of the classic myeloproliferative disorders (MPDs), which include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Nonetheless, genetic defects have not yet been identified in about 40% of ET and PMF. There is now strong evidence that these mutations are the oncogenic events that drive these disorders and are responsible for most biologic and clinical abnormalities. In addition, there are convincing data indicating that the number of JAK2V617F copies (homozygosity vs. heterozygosity) is important in explaining how a single mutation can be associated with several disorders. However, it is still uncertain whether these mutations are sufficient to explain the full development, heterogeneity, and progression of MPD, or if other genetic or epigenetic events are also necessary. In this review, we discuss different hypothetical models of MPD pathogenesis supported by recent findings. Further characterization of the molecular events operating in these disorders will be essential in fully understanding their pathogenesis and in developing new therapeutic approaches.
Clin Lymphoma Myeloma 2009
PMID:Molecular and genetic bases of myeloproliferative disorders: questions and perspectives. 1977 61

Myelofibrosis (MF; primary or post-polycythemia vera/essential thrombocythemia) carries the worst prognosis among BCR-ABL-negative myeloproliferative neoplasms (MPNs). Stem cell transplantation is the only curative approach but is hampered by significant nonrelapse mortality. Thus, effective, targeted therapies are needed. A mutated Janus kinase 2 (JAK2) gene (JAK2(V617F)), found in a significant portion of patients with MPN, results in increased JAK2 tyrosine kinase activity, leading to clonal proliferation; several small molecules inhibit the growth of hematopoietic colonies harboring JAK2(V617). Several JAK2 inhibitors have reached the clinical trial stage and are reviewed here. The most developed among them is INCB018424, which has demonstrated noteworthy clinical activity, with a rapid and profound reduction in splenomegaly and associated improvement in constitutional symptoms in MF patients receiving 10-25 mg orally twice daily, continuously. Thrombocytopenia (reversible) was the most common adverse event, seen in 30% of patients treated with 25 mg twice daily but not with 10 mg twice daily. Interestingly, INCB018424 was equally active in patients with and without JAK2 mutation. Other JAK2 inhibitors are less developed but show a similar type of clinical benefit. Conclusively, JAK2 inhibitors, particularly INCB018424, are clinically active in MF and are well tolerated. Whether they have an effect on the natural course of MF in treated patients remains to be elucidated.
Clin Lymphoma Myeloma 2009
PMID:JAK2 inhibitors: A reality? A hope? 1977 62

We observed that BMSCs (bone marrow stromal cells) from myeloma patients (myeloma BMSCs) were significantly stiffer than control BMSCs using a cytocompression device. The stiffness of myeloma BMSCs and control BMSCs was further increased upon priming by myeloma cells. Additionally, myeloma cells became stiffer when primed by myeloma BMSCs. The focal adhesion kinase activity of myeloma cells was increased when cells were on stiffer collagen gels and on myeloma BMSCs. This change in myeloma stiffness is associated with increased colony formation of myeloma cells and FAK activation when co-cultured with stiffer myeloma BMSCs or stiffer collagen. Additionally, stem cells of RPMI8226 cells became stiffer after priming by myeloma BMSCs, with concomitant increases of stem cell colony formation. These results suggest the presence of a mechanotransduction loop between myeloma cells and myeloma BMSCs to increase the stiffness of both types of cells via FAK activation. The increase of stiffness may in turn support the growth of myeloma cells and myeloma stem cells.
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PMID:Unique biomechanical interactions between myeloma cells and bone marrow stroma cells. 1984 Aug 13

The presence of the JAK2 V617F mutation is now part of clinical diagnostic algorithms, and JAK2 status is routinely assessed when BCR/ABL- chronic myeloproliferative neoplasms (MPNs) are suspected. The aim of this study was to evaluate performance of 3 screening and 1 quantitative method for JAK2 V617F detection. For the study, 43 samples (27 bone marrow aspirates and 16 peripheral blood samples) were selected. The screening assays were the JAK2 Activating Mutation Assay (InVivoScribe, San Diego, CA), JAK2 MutaScreen kit (Ipsogen, Luminy Biotech, Marseille, France), and a home-brew melting curve analysis method. Ipsogen's JAK2 MutaQuant assay was used for quantification of mutant and wild-type alleles. The limit of detection was 1% for the kit-based screening methods and 10% for the melting curve method. The JAK2 MutaQuant assay demonstrated analytic sensitivity of 0.01%. All 4 methods detected cases of BCR/ABL- MPNs and gave negative results with BCR/ABL+ chronic myelogenous leukemia, multiple myeloma, myelodysplastic syndrome, and normal cases.
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PMID:Clinical performance of JAK2 V617F mutation detection assays in a molecular diagnostics laboratory: evaluation of screening and quantitation methods. 1984 12

We report the emergence of chronic myelogenous leukemia (CML) in a patient with JAK2V617F-positive polycythemia vera after 15 years of phlebotomy. The polycythemia vera clinical and molecular findings were suppressed at the time of CML diagnosis, only to re-emerge after the leukemia was successfully treated with imatinib. We explored the potential association between myeloproliferative disorders and CML in the context of the current literature and found a higher-than-expected coincidence based on known epidemiologic data for each specific condition. We hypothesize that myeloproliferative disorder (JAK2V617F or molecular events that cause JAK2V617F) is a risk factor for CML (BCR-ABL translocation). Because of therapeutic implications, clinicians should be aware that the conditions co-occur more frequently than once thought.
Clin Lymphoma Myeloma 2009 Oct
PMID:Emergence of chronic myelogenous leukemia from a background of myeloproliferative disorder: JAK2V617F as a potential risk factor for BCR-ABL translocation. 1985 50

STAT3 activation has been associated with survival, proliferation and invasion of various human cancers. Whether betulinic acid, a pentacyclic triterpene, can modulate the STAT3 pathway, was investigated in human multiple myeloma (MM) cells. We found that betulinic acid inhibited constitutive activation of STAT3, Src kinase, JAK1 and JAK2. Pervanadate reversed the betulinic acid-induced downregulation of STAT3 activation, suggesting the involvement of a protein tyrosine phosphatase (PTP). Furthermore, betulinic acid induced the expression of the PTP SHP-1 and silencing of the SHP-1 gene abolished the ability of betulinic acid to inhibit STAT3 activation and rescued betulinic acid-induced cell death. Betulinic acid also downregulated the expression of STAT3-regulated gene products such as bcl-xL, bcl-2, cyclin D1 and survivin. This correlated with an increase in apoptosis as indicated by an increase in the sub-G1 cell population and an increase in caspase-3-induced PARP cleavage. Consistent with these results, overexpression of constitutive active STAT3 significantly reduced the betulinic acid-induced apoptosis. Betulinic acid also enhanced the apoptosis induced by thalidomide (from 10 to 55%) and bortezomib (from 5 to 70%) in MM cells. Overall, our results suggest that betulinic acid downregulates STAT3 activation through upregulation of SHP-1, and this may have potential in sensitization of STAT3 overexpressing tumors to chemotherapeutic agents.
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PMID:Betulinic acid suppresses STAT3 activation pathway through induction of protein tyrosine phosphatase SHP-1 in human multiple myeloma cells. 1993 97

Imatinib is currently regarded as the best initial treatment for patients with chronic myeloid leukemia (CML). However, a significant proportion of patients who relapse, fail to respond, or develop intolerance might benefit from the use of second-generation tyrosine kinase inhibitors. In this review, we report the 2-year results in 8 clinical trials involving more than 2000 patients treated with dasatinib (phases I-III). Patients with CML who had failed to respond or were intolerant to imatinib were enrolled in a phase I trial. The positive results emanating from this study led to a series of 5 phase II trials known as START (SRC/ABL tyrosine kinase inhibition activity: research trials of dasatinib). In addition, 2 phase III dose-optimization trials have now been completed. These trials demonstrate that dasatinib offers clinical benefit to patients resistant or intolerant to imatinib, with a well-described and manageable adverse event profile.
Clin Lymphoma Myeloma 2009 Dec
PMID:Dasatinib and chronic myeloid leukemia: two-year follow-up in eight clinical trials. 1995 80

A paucity of validated kinase targets in human multiple myeloma has delayed clinical deployment of kinase inhibitors in treatment strategies. We therefore conducted a kinome-wide small interfering RNA (siRNA) lethality study in myeloma tumor lines bearing common t(4;14), t(14;16), and t(11;14) translocations to identify critically vulnerable kinases in myeloma tumor cells without regard to preconceived mechanistic notions. Fifteen kinases were repeatedly vulnerable in myeloma cells, including AKT1, AK3L1, AURKA, AURKB, CDC2L1, CDK5R2, FES, FLT4, GAK, GRK6, HK1, PKN1, PLK1, SMG1, and TNK2. Whereas several kinases (PLK1, HK1) were equally vulnerable in epithelial cells, others and particularly G protein-coupled receptor kinase, GRK6, appeared selectively vulnerable in myeloma. GRK6 inhibition was lethal to 6 of 7 myeloma tumor lines but was tolerated in 7 of 7 human cell lines. GRK6 exhibits lymphoid-restricted expression, and from coimmunoprecipitation studies we demonstrate that expression in myeloma cells is regulated via direct association with the heat shock protein 90 (HSP90) chaperone. GRK6 silencing causes suppression of signal transducer and activator of transcription 3 (STAT3) phosphorylation associated with reduction in MCL1 levels and phosphorylation, illustrating a potent mechanism for the cytotoxicity of GRK6 inhibition in multiple myeloma (MM) tumor cells. As mice that lack GRK6 are healthy, inhibition of GRK6 represents a uniquely targeted novel therapeutic strategy in human multiple myeloma.
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PMID:Kinome-wide RNAi studies in human multiple myeloma identify vulnerable kinase targets, including a lymphoid-restricted kinase, GRK6. 1999 89


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