Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to validate the application of a commercially available multiplex reverse transcription polymerase chain reaction (RT-PCR) assay [Hemavision-7 System] for the seven most common leukemia translocations for routine molecular diagnostic hematopathology practice. A total of 98 samples, comprising four groups, were evaluated: Group 1, 16 diagnostic samples molecularly positive by our existing laboratory-developed assays for PML-RARalpha/t (15;17) or BCR-ABL/t (9;22); Group 2, 51 diagnostic samples negative by our laboratory-developed assays for PML-RARalpha/t (15;17) or BCR-ABL/t (9;22); Group 3, 21 prospectively analyzed diagnostic cases, without prior molecular studies; and Group 4, 10 minimal residual disease (MRD) samples. Analysis of the two previously studied cohorts (Groups 1 and 2) confirmed the diagnostic sensitivity and specificity of the multiplex assay with regard to these two translocations. Additionally, however, in the "negative" Group (Group 2) the assay revealed three unanticipated translocations (CBFbeta-MYH11, BCR-ABL, and MLL-AF4), two of which were confirmed on cytogenetics. Analysis of the prospective cohort demonstrated that the assay was cost-effective and amenable to standard laboratory practice, with an identically sensitive MRD detection rate to that of our laboratory-developed tests. Virtually all of the results obtained were consistent with the phenotype and karyotype by conventional methods. This study illustrates the utility of a kit-based multiplex RT-PCR assay for the molecular diagnosis and monitoring of leukemias and reinforces the complementary roles of molecular testing and cytogenetics in diagnostic hematopathology.
J Mol Diagn 2003 Nov
PMID:Multiplex RT-PCR for the detection of leukemia-associated translocations: validation and application to routine molecular diagnostic practice. 1457 82

The acute myeloid leukemia (AML)-associated translocation products AML1-ETO, PML-retinoic acid receptor alpha (RARalpha), and PLZF-RARalpha encode aberrant transcription factors. Several lines of evidence suggest similar pathogenetic mechanisms for these fusion proteins. We used high-density oligonucleotide arrays to identify shared target genes in inducibly transfected U937 cells expressing AML1-ETO, PML-RARalpha, or PLZF-RARalpha. All three fusion proteins significantly repressed the expression of 38 genes and induced the expression of 14 genes. Several of the regulated genes were associated with Wnt signaling. One of these, plakoglobin (gamma-catenin), was induced on the mRNA and protein level by all three fusion proteins. In addition, primary AML blasts carrying one of the fusion proteins significantly overexpressed plakoglobin. The plakoglobin promoter was cloned and shown to be induced by AML1-ETO, with promoter activation depending on the corepressor and histone deacetylase binding domains. The induction of plakoglobin by AML fusion proteins led to downstream signaling and transactivation of TCF- and LEF-dependent promoters, including the c-myc promoter, which was found to be bound by plakoglobin in vivo after AML1-ETO expression. beta-Catenin protein levels and TCF and LEF target genes such as c-myc and cyclin D1 were found to be induced by the fusion proteins. On the functional level, a dominant negative TCF inhibited colony growth of AML1-ETO-positive Kasumi cells, whereas plakoglobin transfection into myeloid 32D cells enhanced proliferation and clonal growth. Injection of plakoglobin-expressing 32D cells into syngeneic mice accelerated the development of leukemia. Transduction of plakoglobin into primitive murine hematopoietic progenitor cells preserved the immature phenotype during colony growth, suggesting enhanced self-renewal. These data provide evidence that activation of Wnt signaling is a common feature of several balanced translocations in AML.
Mol Cell Biol 2004 Apr
PMID:Translocation products in acute myeloid leukemia activate the Wnt signaling pathway in hematopoietic cells. 1502 77

Several lines of evidence suggest that gene expression is regulated not only by the interaction between transcription factors and DNA but also by the higher-order architecture of the cell nucleus. PML bodies are one of the most prominent nuclear substructures which have been implicated in transcription regulation during apoptosis and stress responses. Bach2 is a member of the BTB-basic region leucine zipper factor family and represses transcription activity directed by the 12-O-tetradecanoylphorbol-13-acetate response element, the Maf recognition element, and the antioxidant-responsive element. Bach2 forms nuclear foci associated with PML bodies upon oxidative stress. Here, we demonstrate that transcription activity associated with PML bodies is selectively repressed by the recruitment of Bach2 around PML bodies. Fluorescence recovery after photobleaching experiments revealed that Bach2 showed rapid turnover in the nuclear foci. The Bach2 N-terminal region including the BTB domain is essential for the focus formation. Sumoylation of Bach2 is required for the recruitment of the protein around PML bodies. These observations represent the first example of modulation of transcription activity associated with PML bodies by a sequence-specific transcription factor upon oxidative stress.
Mol Cell Biol 2004 Apr
PMID:Repression of PML nuclear body-associated transcription by oxidative stress-activated Bach2. 1506 Jan 66

Ankrd2 may be a link between the sarcomere and the nucleus; a similar role has recently been proposed for CARP that has a high level of structural and functional conservation with Ankrd2. Both Ankrd2 and CARP are involved in striated muscle hypertrophy. The mechanism by which muscle stretch is sensed and signals are transduced is still unknown; however, Ankrd2 and CARP could play similar roles in pathways leading to hypertrophy, the triggering mechanisms being heart pressure overload monitored by CARP and mechanical stretch in skeletal muscle monitored by Ankrd2. Recently Ankrd2 and CARP have been proposed as members of a family of muscle ankyrin repeat proteins (MARPs) that form a complex with titin, myopalladin and calpain protease p94, involved in signaling and regulation of gene expression in response to muscle stress. Here, we show that Ankrd2 is able to interact with the Z-disc protein telethonin as well as being able to interact with three transcription factors: YB-1, PML and p53. Ankrd2 binding to the ubiquitous transcription factor YB-1 can be demonstrated both in vitro and in vivo; this is not very surprising, since a similar interaction was previously described for CARP. However, the interactions with PML and p53 are unexpected new findings, with interesting implications in the Ankrd2 signaling cascade. Ankrd2 co-localizes with the transcriptional co-activator and co-repressor PML in nuclear bodies (NBs) in human myoblasts as detected by confocal immunofluorescence. Interestingly, we show that Ankrd2 not only binds the tumor suppressor protein p53 both in vitro and in vivo but also enhances the up-regulation of the p21(WAFI/CIPI) promoter by p53. Therefore, our findings strengthen the hypothesis that Ankrd2 may be involved in sensing stress signals and linking these to muscle gene regulation.
J Mol Biol 2004 May 28
PMID:The Ankrd2 protein, a link between the sarcomere and the nucleus in skeletal muscle. 1513 35

We evaluated 2 methods, a LightCycler PCR assay and pyrosequencing for the detection of the JC polyoma virus (JCV) in fixed brain tissue of 10 patients with and 3 control patients without progressive multifocal leukoencephalopathy (PML). Nucleic acid extraction was performed after deparaffinization and proteinase K digestion. The LightCycler assay differentiates the BK virus (BKV), JCV, and SV40 using melt curve analysis. Conventional PCR was used with the same primers to generate products for pyrosequencing. Two sequencing primers were used that differentiate the polyoma viruses. Seven of 11 biopsies (1 patient had 2 biopsies) with PML were positive for JCV by real-time PCR and/or PCR/pyrosequencing. Three of 4 remaining biopsies were positive by real-time PCR but had melting points between JCV and SV40. The 4 specimens that were negative or atypical by LightCycler PCR were positive by traditional PCR, but 1 had an amplicon of lower molecular weight by gel electrophoresis. These were shown to represent JCV by at least 1 of the 2 pyrosequencing primers. The biopsies from patients without PML were PCR negative. Both the LightCycler and pyrosequencing assays are useful for confirming JCV in brain biopsies from patients with PML, but variant JCVs may require supplementary methods to confirm JCV infection.
Diagn Mol Pathol 2004 Mar
PMID:Detection of polyoma virus in brain tissue of patients with progressive multifocal leukoencephalopathy by real-time PCR and pyrosequencing. 1516 4

Nuclear foci containing the promyelocytic leukemia protein (PML bodies), which occur in most cells, play a role in tumor suppression. Here, we demonstrate that CHFR, a mitotic checkpoint protein frequently inactivated in human cancers, is a dynamic component of PML bodies. Intermolecular fluorescence resonance energy transfer analysis identified a distinct fraction of CHFR that interacts with PML in living cells. This interaction modulates the nuclear distribution and mobility of CHFR. A trans-dominant mutant of CHFR that inhibits checkpoint function also prevents colocalization and interaction with PML. Conversely, the distribution and mobility of CHFR are perturbed in PML(-/-) cells, accompanied by aberrations in mitotic entry and the response to spindle depolymerization. Thus, PML bodies control the distribution, dynamics and function of CHFR. Our findings implicate the interaction between these tumor suppressors in a checkpoint response to microtubule poisons, an important class of anticancer drugs.
Nat Struct Mol Biol 2004 Nov
PMID:PML bodies control the nuclear dynamics and function of the CHFR mitotic checkpoint protein. 1546 28

JC virus (JCV) belongs to the family of double-stranded DNA polyomaviruses and in humans causes a demyelinating disease of the central nervous system, progressive multifocal leukoencephalopathy (PML). It has been reported that sialic acids play a pivotal role in hemagglutination of red blood cells and entry into host cells of JCV and that JCV can enter a wide variety of cell types and localize to the nuclei. The outer shell of the JCV virion comprises the major capsid protein VP1, and a virus-like particle (VLP) consisting of recombinant VP1 made from Escherichia coli exhibit a virion-like structure and physiological functions (cellular attachment and intracytoplasmic trafficking) similar to those of JCV virions. To examine the mechanism of cell attachment of JCV, an overlay assay using a VLP has been developed, revealing that sialoglycoproteins, including alpha1 acid-glycoprotein, fetuin, and transferrin receptor bind with VLP. In addition, VLPs bind to glycolipids, such as lactosylceramide and gangliosides including GM3, GD2, GD3, GD1b, GT1b, and GQ1b, and VLP weakly bind to GD1a. In this section, detailed procedures for the synthesis of VLP from E. coli and VLP overlay assay are described.
Methods Mol Biol 2005
PMID:The JC virus-like particle overlay assay. 1550 8

Leukemia results from the expansion of self-renewing hematopoietic cells that are thought to contain mutations that contribute to disease initiation and progression. Studies of the gene expression profiles of human acute myeloid leukemia samples has allowed their classification based on the presence of translocations and French-American-British subtypes, but it is not yet clear whether their molecular signatures reflect the initiating mutations or mutations acquired during progression. To begin to address this question, we examined the expression profiles of normal murine promyelocyte-enriched samples, nontransformed murine promyelocytes expressing human promyelocytic leukemia-retinoic acid receptor alpha (PML-RARalpha) fusion gene, and primary acute promyelocytic leukemia cells. The expression profile of nontransformed cells expressing PML-RARalpha was remarkably similar to that of wild-type promyelocytes. In contrast, the expression profiles of fully transformed cells from three acute promyelocytic leukemia model systems were all different, suggesting that the expression signature of acute promyelocytic leukemia cells reflects the genetic changes that contributed to progression. To further evaluate these progression events, we compared two high-penetrance acute promyelocytic leukemia models that both commonly acquire an interstitial deletion of chromosome 2 during progression. The two models exhibited distinct gene expression profiles, suggesting that the dominant molecular signatures of murine acute promyelocytic leukemia can be influenced by several independent progression events.
Mol Cell Biol 2004 Dec
PMID:Expression profiling of murine acute promyelocytic leukemia cells reveals multiple model-dependent progression signatures. 1557 90

PML-retinoic acid receptor alpha (RARalpha) regulated adaptor molecule 1 (PRAM-1) is an intracellular adaptor molecule that is upregulated during the induced granulocytic differentiation of promyelocytic leukemic cells and during normal human myelopoiesis. This report describes the generation of PRAM-1-deficient mice and an analysis of the function of this adaptor in neutrophil differentiation and mature neutrophil function. We demonstrate here that neutrophil differentiation is not impaired in PRAM-1-deficient mice and that PRAM-1-deficient neutrophils function normally following engagement of Fcgamma receptors. In contrast, mature PRAM-1-null neutrophils exhibit significant defects in adhesion-dependent reactive oxygen intermediate production and degranulation. Surprisingly, other integrin-dependent responses, such as cell spreading and activation of several signaling pathways, are normal. Together, these findings demonstrate the uncoupling of key integrin-dependent responses in the absence of PRAM-1 and show this adaptor to be critical for select integrin functions in neutrophils.
Mol Cell Biol 2004 Dec
PMID:PRAM-1 is required for optimal integrin-dependent neutrophil function. 1557 93

Expression of the PML-retinoic acid receptor alpha (PML-RARalpha) fusion protein is the initiating genetic event for acute promyelocytic leukemia (APL), but the molecular mechanisms responsible for disease initiation are not yet clear. Several observations have suggested that early myeloid cells are uniquely susceptible to transformation by PML-RARalpha. Recently, we have shown that the early myeloid-specific protease neutrophil elastase is important for APL development in the mouse. To better understand the role of neutrophil elastase for the pathogenesis of APL, we examined the consequences of PML-RARalpha expression in early myeloid cells with or without neutrophil elastase. We found that high-level PML-RARalpha expression was associated with cellular toxicity that was dependent on the expression of neutrophil elastase; a mutant form of PML-RARalpha that resisted neutrophil elastase cleavage was not toxic. When PML-RARalpha was expressed at very low levels in the early myeloid cells of mice, it induced myeloid expansion and delayed myeloid maturation; neutrophil elastase was also required for these activities. The activities of PML-RARalpha in early myeloid cells are therefore strongly influenced by the presence of neutrophil elastase. To assure physiologic relevance, PML-RARalpha functions should be evaluated in neutrophil elastase-expressing early myeloid cells.
Mol Cell Biol 2005 Jan
PMID:Neutrophil elastase is important for PML-retinoic acid receptor alpha activities in early myeloid cells. 1560 27


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