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Deutsch JL, Heath JL. MLLT10 in benign and malignant hematopoiesis. Exp Hematol 2020; 87:1-12. [PMID: 32569758 DOI: 10.1016/j.exphem.2020.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/16/2020] [Accepted: 06/18/2020] [Indexed: 01/01/2023]
Abstract
Non-random chromosomal translocations involving the putative transcription factor Mixed Lineage Leukemia Translocated to 10 (MLLT10, also known as AF10) are commonly observed in both acute myeloid and lymphoid leukemias and are indicative of a poor prognosis. Despite the well-described actions of oncogenic MLLT10 fusion proteins, the role of wild-type MLLT10 in hematopoiesis is not well characterized. The protein structure and several interacting partners have been described and provide indications as to the potential functions of MLLT10. This review examines these aspects of MLLT10, contextualizing its function in benign and malignant hematopoiesis.
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Affiliation(s)
- Jamie L Deutsch
- Department of Pediatrics, University of Vermont, Burlington, VT
| | - Jessica L Heath
- Department of Pediatrics, University of Vermont, Burlington, VT; Department of Biochemistry, University of Vermont, Burlington, VT 05405; University of Vermont Cancer Center, Burlington, VT.
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2
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Abstract
Chimeric RNAs are hybrid transcripts containing exons from two separate genes. Chimeric RNAs are traditionally considered to be transcribed from fusion genes caused by chromosomal rearrangement. These canonical chimeric RNAs are well characterized to be expressed in a cancer-unique pattern and/or act as oncogene products. However, benefited by the development of advanced deep sequencing technologies, novel types of non-canonical chimeric RNAs have been discovered to be generated from intergenic splicing without genomic aberrations. They can be formed through trans-splicing or cis-splicing between adjacent genes (cis-SAGe) mechanisms. Non-canonical chimeric RNAs are widely detected in normal physiology, although several have been shown to have a cancer-specific expression pattern. Further studies have indicated that some of them play fundamental roles in controlling cell growth and motility, and may have functions independent of the parental genes. These discoveries are unveiling a new layer of the functional transcriptome and are also raising the possibility of utilizing non-canonical chimeric RNAs as cancer diagnostic markers and therapeutic targets. In this chapter, we will overview different categories of chimeric RNAs and their expression in various types of cancerous and normal samples. Acknowledging that chimeric RNAs are not unique to cancer, we will discuss both bioinformatic and biological methods to identify credible cancer-specific chimeric RNAs. Furthermore, we will describe downstream methods to explore their molecular processing mechanisms and potential functions. A better understanding of the biogenesis mechanisms and functional products of cancer-specific chimeric RNAs will pave ways for the development of novel cancer biomarkers and therapeutic targets.
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Affiliation(s)
- Xinrui Shi
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Sandeep Singh
- Department of Pathology, School of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Emily Lin
- Department of Pathology, School of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Hui Li
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Charlottesville, VA, United States; Department of Pathology, School of Medicine, University of Virginia, Charlottesville, VA, United States.
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Muhlbauer N, MacDonell-Yilmaz RE, Borsuk R, Welch JG. Mutations within the Activation Loop Domain of FLT3 in Two Pediatric Patients with Refractory Infant Acute Myeloid Leukemia. Case Rep Oncol 2020; 13:266-270. [PMID: 32308588 PMCID: PMC7154245 DOI: 10.1159/000506194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 01/24/2020] [Indexed: 11/19/2022] Open
Abstract
Approximately 24% of all pediatric acute myeloid leukemia (AML) cases have mutations in the FMS-like tyrosine kinase 3 (<i>FLT3</i>) receptor gene. FLT3-TKD point mutations are rare in pediatrics and often occur in younger patients and in combination with 11q23 abnormalities. There is a paucity of data related to their prognostic implications in children. We describe 2 pediatric patients with FLT3-activating mutations as a feature of their AML. Both were diagnosed in infancy. The first experienced induction failure and had refractory disease without expression of FLT3-TKD mutation on subsequent bone marrow evaluations. His disease also harbored a KMT2A-PICALM gene rearrangement. He died of invasive fungal disease nine months after diagnosis. The second had a post-induction remission but developed swelling of the left calcaneus shown on biopsy to be a myeloid sarcoma positive for a new BRAF V600E mutation in addition to his known KMT2A rearrangement but without FLT3-TKD mutation. Despite multiple courses of therapy including BRAF/MEK-inhibition, he died of progressive disease nine months after diagnosis. FLT3 inhibition was not utilized in either patient as studies have largely focused on its role in internal tandem duplication (ITD) mutations and because the mutation was no longer detectable in either patient on subsequent evaluation. However, these cases add to the suggestion that these mutations confer a worse prognosis in pediatric AML patients.
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Affiliation(s)
- Nicole Muhlbauer
- Division of Pediatric Hematology/Oncology, Stony Brook University Hospital, Stony Brook, New York, USA
| | - Rebecca E. MacDonell-Yilmaz
- Division of Pediatric Hematology/Oncology, Brown University/Hasbro Children's Hospital, Providence, Rhode Island, USA
- *Dr. Rebecca E. MacDonell-Yilmaz, Division of Pediatric Hematology/Oncology, Brown University/Hasbro Children's Hospital, 593 Eddy St., Providence, RI 02903 (USA),
| | - Robyn Borsuk
- Division of Pediatric Hematology/Oncology, Brown University/Hasbro Children's Hospital, Providence, Rhode Island, USA
| | - Jennifer G. Welch
- Division of Pediatric Hematology/Oncology, Brown University/Hasbro Children's Hospital, Providence, Rhode Island, USA
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4
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Do cognitive and neuropsychological functioning deficits coincide with hippocampal alteration during first-psychotic episode? CNS Spectr 2019; 24:472-478. [PMID: 30507369 DOI: 10.1017/s1092852918001293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Numerous studies shown that structural hippocampal alterations are present in subjects at high risk of developing psychosis or schizophrenia. These findings indicate that in a subset of patients undergoing first-psychosis episode (FPE), hippocampal volume alterations are accompanied by associated cognitive and neuropsychological deficits. The combination of psychological deficits and neuroanatomical alterations, in turn, appears to increase treatment complexity and worsen clinical outcomes. OBJECTIVE We aim to determine whether cognitive and neuropsychological functioning deficits precede or follow hippocampal alterations during early onset psychosis. METHODS This cross-sectional study describes 3 case-studies of adolescent subjects, ages 16-17, admitted at the child and adolescent inpatient psychiatric unit in lieu of first psychotic episode. We conducted detailed structured clinical psychiatric interviews, anatomical-structural magnetic resonance imaging (MRI), sleep-deprived electroencephalogram (EEG) recordings, laboratory testing, and a comprehensive battery of psychological testing to better understand their clinical pictures. RESULTS Psychological testing in each patient demonstrated the presence of low to borderline intellectual functioning coupled with neuropsychological deficits in different psychiatric domains. Interestingly, these changes coincided with structural MRI alterations in the hippocampal area. CONCLUSIONS Our case report adds to the armamentarium of literature signifying that radiologically detectable alterations of the hippocampus may occur either concomitantly or closely following the development of early cognitive deficits in patients with FPE.
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Chwalenia K, Facemire L, Li H. Chimeric RNAs in cancer and normal physiology. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 8. [DOI: 10.1002/wrna.1427] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Katarzyna Chwalenia
- Department of Pathology, School of Medicine; University of Virginia; Charlottesville VA USA
| | - Loryn Facemire
- Department of Pathology, School of Medicine; University of Virginia; Charlottesville VA USA
| | - Hui Li
- Department of Pathology, School of Medicine; University of Virginia; Charlottesville VA USA
- Department of Biochemistry and Molecular Genetics, School of Medicine; University of Virginia; Charlottesville VA USA
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6
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Abstract
Gene fusions and their encoded products (fusion RNAs and proteins) are viewed as one of the hallmarks of cancer. Traditionally, they were thought to be generated solely by chromosomal rearrangements. However, recent discoveries of trans-splicing and cis-splicing events between neighboring genes, suggest that there are other mechanisms to generate chimeric fusion RNAs without corresponding changes in DNA. In addition, chimeric RNAs have been detected in normal physiology, complicating the use of fusions in cancer detection and therapy. On the other hand, "intergenically spliced" fusion RNAs represent a new repertoire of biomarkers and therapeutic targets. Here, we review current knowledge on chimeric RNAs and implications for cancer detection and treatment, and discuss outstanding questions for the advancement of the field.
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Affiliation(s)
- Yuemeng Jia
- Department of Pathology, School of Medicine, University of Virginia, Charlottesville, VA 22908
| | - Zhongqiu Xie
- Department of Pathology, School of Medicine, University of Virginia, Charlottesville, VA 22908
| | - Hui Li
- Department of Pathology, School of Medicine, University of Virginia, Charlottesville, VA 22908
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Charlottesville, VA 22908
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7
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Sen K, Sarkar A, Maji RK, Ghosh Z, Gupta S, Ghosh TC. Deciphering the cross-talking of human competitive endogenous RNAs in K562 chronic myelogenous leukemia cell line. MOLECULAR BIOSYSTEMS 2016; 12:3633-3642. [DOI: 10.1039/c6mb00568c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chronic myelogenous leukemia (CML) is a myeloproliferative disorder characterized by increased proliferation or abnormal accumulation of the granulocytic cell line without the depletion of their capacity to differentiate.
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Affiliation(s)
- Kamalika Sen
- Bioinformatics Centre
- Bose Institute
- Kolkata-700 054
- India
| | | | | | - Zhumur Ghosh
- Bioinformatics Centre
- Bose Institute
- Kolkata-700 054
- India
| | - Sanjib Gupta
- Bioinformatics Centre
- Bose Institute
- Kolkata-700 054
- India
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Zhou J, Liao J, Zheng X, Shen H. Chimeric RNAs as potential biomarkers for tumor diagnosis. BMB Rep 2014; 45:133-40. [PMID: 22449698 DOI: 10.5483/bmbrep.2012.45.3.133] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Cancers claim millions of lives each year. Early detection that can enable a higher chance of cure is of paramount importance to cancer patients. However, diagnostic tools for many forms of tumors have been lacking. Over the last few years, studies of chimeric RNAs as biomarkers have emerged. Numerous reports using bioinformatics and screening methodologies have described more than 30,000 expressed sequence tags (EST) or cDNA sequences as putative chimeric RNAs. While cancer cells have been well known to contain fusion genes derived from chromosomal translocations, rearrangements or deletions, recent studies suggest that trans-splicing in cells may be another source of chimeric RNA production. Unlike cis-splicing, trans-splicing takes place between two pre-mRNA molecules, which are in most cases derived from two different genes, generating a chimeric non-co-linear RNA. It is possible that trans-splicing occurs in normal cells at high frequencies but the resulting chimeric RNAs exist only at low levels. However the levels of certain RNA chimeras may be elevated in cancers, leading to the formation of fusion genes. In light of the fact that chimeric RNAs have been shown to be overrepresented in various tumors, studies of the mechanisms that produce chimeric RNAs and identification of signature RNA chimeras as biomarkers present an opportunity for the development of diagnoses for early tumor detection.
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Affiliation(s)
- Jianhua Zhou
- Nantong University, Nantong, JiangSu, P. R. China
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9
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The ∼ 16 kDa C-terminal sequence of clathrin assembly protein AP180 is essential for efficient clathrin binding. PLoS One 2014; 9:e110557. [PMID: 25329427 PMCID: PMC4203807 DOI: 10.1371/journal.pone.0110557] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 09/22/2014] [Indexed: 11/19/2022] Open
Abstract
Brain-specific AP180 is present in clathrin coats at equal concentration to the adapter complex, AP2, and assembles clathrin faster than any other protein in vitro. Both AP180 and its ubiquitously expressed homolog clathrin assembly lymphoid myeloid leukemia protein (CALM) control vesicle size and shape in clathrin mediated endocytosis. The clathrin assembly role of AP180 is mediated by a long disordered C-terminal assembly domain. Within this assembly domain, a central acidic clathrin and adapter binding (CLAP) sub-domain contains all of the known short binding motifs for clathrin and AP2. The role of the remaining ∼ 16 kDa C-terminal sequence has not been clear. We show that this sequence has a separate function in ensuring efficient binding of clathrin, based on in vitro binding and ex vivo transferrin uptake assays. Sequence alignment suggests the C-terminal sub-domain is conserved in CALM.
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Effects of iron depletion on CALM-AF10 leukemias. Exp Hematol 2014; 42:1022-1030.e1. [PMID: 25193880 DOI: 10.1016/j.exphem.2014.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 08/21/2014] [Accepted: 08/25/2014] [Indexed: 12/18/2022]
Abstract
Iron, an essential nutrient for cellular growth and proliferation, enters cells via clathrin-mediated endocytosis. The clathrin assembly lymphoid myeloid (CALM) protein plays an essential role in the cellular import of iron by clathrin-mediated endocytosis. CALM-AF10 leukemias harbor a single copy of the normal CALM gene and therefore may be more sensitive to the growth-inhibitory effect of iron restriction compared with normal hematopoietic cells. We found that CALM heterozygous (CALM(HET)) murine fibroblasts exhibit signs of iron deficiency, with increased surface transferrin receptor levels and reduced growth rates. CALM(HET) hematopoietic cells are more sensitive in vitro to iron chelators than their wild type counterparts. Iron chelation also displayed toxicity toward cultured CALM(HET)CALM-AF10 leukemia cells, and this effect was additive to that of chemotherapy. In mice transplanted with CALM(HET)CALM-AF10 leukemia, we found that dietary iron restriction reduced tumor burden in the spleen. However, dietary iron restriction, used alone or in conjunction with chemotherapy, did not increase survival of mice with CALM(HET)CALM-AF10 leukemia. In summary, although CALM heterozygosity results in iron deficiency and increased sensitivity to iron chelation in vitro, our data in mice do not suggest that iron depletion strategies would be beneficial for the therapy of CALM-AF10 leukemia patients.
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11
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Suzuki M, Yamagata K, Shino M, Aikawa Y, Akashi K, Watanabe T, Kitabayashi I. Nuclear export signal within CALM is necessary for CALM-AF10-induced leukemia. Cancer Sci 2014; 105:315-23. [PMID: 24397609 PMCID: PMC4317939 DOI: 10.1111/cas.12347] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 12/05/2013] [Accepted: 12/30/2013] [Indexed: 01/24/2023] Open
Abstract
The CALM–AF10 fusion gene, which results from a t(10;11) translocation, is found in a variety of hematopoietic malignancies. Certain HOXA cluster genes and MEIS1 genes are upregulated in patients and mouse models that express CALM-AF10. Wild-type clathrin assembly lymphoid myeloid leukemia protein (CALM) primarily localizes in a diffuse pattern within the cytoplasm, whereas AF10 localizes in the nucleus; however, it is not clear where CALM-AF10 acts to induce leukemia. To investigate the influence of localization on leukemogenesis involving CALM-AF10, we determined the nuclear export signal (NES) within CALM that is necessary and sufficient for cytoplasmic localization of CALM-AF10. Mutations in the NES eliminated the capacity of CALM-AF10 to immortalize murine bone-marrow cells in vitro and to promote development of acute myeloid leukemia in mouse models. Furthermore, a fusion of AF10 with the minimal NES can immortalize bone-marrow cells and induce leukemia in mice. These results suggest that during leukemogenesis, CALM-AF10 plays its critical roles in the cytoplasm.
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Affiliation(s)
- Mai Suzuki
- Division of Hematological Malignancy, National Cancer Center Research Institute, Tokyo, Japan
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12
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Chen Y, Kantarjian H, Pierce S, Faderl S, O'Brien S, Qiao W, Abruzzo L, de Lima M, Kebriaei P, Jabbour E, Daver N, Kadia T, Estrov Z, Garcia-Manero G, Cortes J, Ravandi F. Prognostic significance of 11q23 aberrations in adult acute myeloid leukemia and the role of allogeneic stem cell transplantation. Leukemia 2012; 27:836-42. [PMID: 23135353 DOI: 10.1038/leu.2012.319] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The clinical features and outcomes of 148 patients with acute myeloid leukemia (AML) and 11q23 chromosomal abnormalities were compared with those of 2640 patients with non-11q23 AML. Patients with t(9;11) ), t(6;11) or other 11q23 balanced translocations (t(11;v)(q23;v)) presented at a younger age and with higher percentage of bone marrow blasts. Unbalanced 11q23 abnormalities were commonly associated with deletions of chromosomes 5q, 7q and/or complex karyotypes. In multivariate analysis, when compared with patients with non-11q23 AML and unfavorable-risk karyotype, there was a significant difference in overall survival (OS) for patients with t(9;11) (P=0.004), whereas there were no differences in OS for patients with t(6;11) (P=0.62), t(11;19) (P=0.20) and unbalanced 11q23 aberrations (P=0.85) or t(11;v)(q23;v) (P=0.59), indicating that t(9;11) has an independent intermediate prognostic significance, with all others being poor prognostic factors for OS; this was further confirmed by comparing them with patients with non-11q23 AML and intermediate-risk karyotype. Using intention-to treat analysis based on donor availability, we also noted that allogeneic stem cell transplant in first remission had a significant benefit toward improving OS (P<0.001) and relapse-free survival (P<0.001) in patients with AML and 11q23 abnormalities.
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Affiliation(s)
- Y Chen
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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The PICALM protein plays a key role in iron homeostasis and cell proliferation. PLoS One 2012; 7:e44252. [PMID: 22952941 PMCID: PMC3431333 DOI: 10.1371/journal.pone.0044252] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 07/31/2012] [Indexed: 01/16/2023] Open
Abstract
The ubiquitously expressed phosphatidylinositol binding clathrin assembly (PICALM) protein associates with the plasma membrane, binds clathrin, and plays a role in clathrin-mediated endocytosis. Alterations of the human PICALM gene are present in aggressive hematopoietic malignancies, and genome-wide association studies have recently linked the PICALM locus to late-onset Alzheimer's disease. Inactivating and hypomorphic Picalm mutations in mice cause different degrees of severity of anemia, abnormal iron metabolism, growth retardation and shortened lifespan. To understand PICALM’s function, we studied the consequences of PICALM overexpression and characterized PICALM-deficient cells derived from mutant fit1 mice. Our results identify a role for PICALM in transferrin receptor (TfR) internalization and demonstrate that the C-terminal PICALM residues are critical for its association with clathrin and for the inhibitory effect of PICALM overexpression on TfR internalization. Murine embryonic fibroblasts (MEFs) that are deficient in PICALM display several characteristics of iron deficiency (increased surface TfR expression, decreased intracellular iron levels, and reduced cellular proliferation), all of which are rescued by retroviral PICALM expression. The proliferation defect of cells that lack PICALM results, at least in part, from insufficient iron uptake, since it can be corrected by iron supplementation. Moreover, PICALM-deficient cells are particularly sensitive to iron chelation. Taken together, these data reveal that PICALM plays a critical role in iron homeostasis, and offer new perspectives into the pathogenesis of PICALM-associated diseases.
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Stoddart A, Tennant TR, Fernald AA, Anastasi J, Brodsky FM, Le Beau MM. The clathrin-binding domain of CALM-AF10 alters the phenotype of myeloid neoplasms in mice. Oncogene 2011; 31:494-506. [PMID: 21706055 PMCID: PMC3204175 DOI: 10.1038/onc.2011.251] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The PICALM (CALM) gene, whose product is involved in clathrin-mediated endocytosis, has been identified in two recurring chromosomal translocations, involving either MLL or MLLT10 (AF10). We developed a mouse model of CALM-AF10+ leukemia to examine the hypothesis that disruption of endocytosis contributes to leukemogenesis. Exclusion of the C-terminal portion of CALM from the fusion protein, which is required for optimal binding to clathrin, resulted in the development of a myeloproliferative disease, while inclusion of this domain led to the development of acute myeloid leukemia and changes in gene expression of several cancer-related genes, notably Pim1 and Crebbp. Nonetheless, the development of leukemia could not be attributed directly to interference with endocytosis or consequential changes in proliferation and signaling. In leukemia cells, full-length CALM-AF10 localized to the nucleus with no consistent effect on growth factor endocyctosis, and suppressed H3K79 methylation regardless of the presence of clathrin. Using FRET analysis, we show that CALM-AF10 has a propensity to homo-oligomerize, raising the possibility that the function of endocytic proteins involved in chimeric fusions may be to provide dimerization properties, a recognized mechanism for unleashing oncogenic properties of chimeric transcription factors, rather than disrupting the internalization of growth factor receptors.
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Affiliation(s)
- A Stoddart
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL 60637, USA.
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15
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Deshpande AJ, Rouhi A, Lin Y, Stadler C, Greif PA, Arseni N, Opatz S, Quintanilla-Fend L, Holzmann K, Hiddemann W, Döhner K, Döhner H, Xu G, Armstrong SA, Bohlander SK, Buske C. The clathrin-binding domain of CALM and the OM-LZ domain of AF10 are sufficient to induce acute myeloid leukemia in mice. Leukemia 2011; 25:1718-27. [PMID: 21681188 DOI: 10.1038/leu.2011.153] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The t(10;11)(p13-14;q14-21) translocation, giving rise to the CALM-AF10 fusion gene, is a recurrent chromosomal rearrangement observed in patients with poor prognosis acute myeloid leukemia (AML). Although splicing of the CALM-AF10 fusion transcripts has been described in AML patients, the contribution of different CALM and AF10 domains to in vivo leukemogenesis remains to be defined. We therefore performed detailed structure-function studies of the CALM-AF10 fusion protein. We demonstrate that fusion of the C-terminal 248 amino acids of CALM, which include the clathrin-binding domain, to the octapeptide motif-leucine-zipper (OM-LZ) domain of AF10 generated a fusion protein (termed CALM-AF10 minimal fusion (MF)), with strikingly enhanced transformation capabilities in colony assays, providing an efficient system for the expeditious assessment of CALM-AF10-mediated transformation. Leukemias induced by the CALM-AF10 (MF) mutant recapitulated multiple aspects of full-length CALM-AF10-induced leukemia, including aberrant Hoxa cluster upregulation, a characteristic molecular lesion of CALM-AF10 leukemias. In summary, this study indicates that collaboration of the clathrin-binding and the OM-LZ domains of CALM-AF10 is sufficient to induce AML. These findings further suggest that future approaches to antagonize CALM-AF10-induced transformation should incorporate strategies, which aim at blocking these key domains.
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Affiliation(s)
- A J Deshpande
- Department of Medicine III, Klinikum Grosshadern, Munich, Germany
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16
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Yu JT, Song JH, Ma T, Zhang W, Yu NN, Xuan SY, Tan L. Genetic association of PICALM polymorphisms with Alzheimer's disease in Han Chinese. J Neurol Sci 2011; 300:78-80. [DOI: 10.1016/j.jns.2010.09.027] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Accepted: 09/22/2010] [Indexed: 11/25/2022]
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17
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De Braekeleer E, Meyer C, Douet-Guilbert N, Morel F, Le Bris MJ, Berthou C, Arnaud B, Marschalek R, Férec C, De Braekeleer M. Complex and cryptic chromosomal rearrangements involving the MLL gene in acute leukemia: A study of 7 patients and review of the literature. Blood Cells Mol Dis 2010; 44:268-74. [DOI: 10.1016/j.bcmd.2010.02.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 02/03/2010] [Indexed: 11/30/2022]
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18
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Sleegers K, Lambert JC, Bertram L, Cruts M, Amouyel P, Van Broeckhoven C. The pursuit of susceptibility genes for Alzheimer's disease: progress and prospects. Trends Genet 2010; 26:84-93. [PMID: 20080314 DOI: 10.1016/j.tig.2009.12.004] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 12/10/2009] [Accepted: 12/11/2009] [Indexed: 11/19/2022]
Abstract
The recent discoveries in genome-wide association studies (GWAS) of novel susceptibility loci (CLU, CR1 and PICALM) for Alzheimer's disease (AD) have elicited considerable interest in the AD community. But what are the implications of these purely epidemiological findings for our understanding of disease etiology and patient care? In this review, we attempt to place these findings in the context of current and future AD genetics research. CLU, CR1 and PICALM support existing hypotheses about the amyloid, lipid, chaperone and chronic inflammatory pathways in AD pathogenesis. We discuss how these and future findings can be translated into efforts to ameliorate patient care by genetic profiling for risk prediction and pharmacogenetics and by guiding drug development.
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Affiliation(s)
- Kristel Sleegers
- Neurodegenerative Brain Diseases Group, VIB-Department of Molecular Genetics; Universiteitsplein 1, B-2610 Antwerp, Belgium
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Panhandle PCR approaches to cloning MLL genomic breakpoint junctions and fusion transcript sequences. Methods Mol Biol 2009; 538:85-114. [PMID: 19277575 DOI: 10.1007/978-1-59745-418-6_6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
Translocations and other rearrangements of the MLL gene at chromosome band 11q23 are biologically and clinically important molecular abnormalities in infant acute leukemias, leukemias associated with chemotherapeutic topoisomerase II poisons and, less often, acute leukemias in adults or myelodysplastic syndrome. Depending on the disease and the regimen, MLL-rearranged leukemias may be associated with inferior prognosis, and MLL rearrangements with some of the more than 60 known MLL-partner genes confer especially adverse effects as response to treatment (Blood 108:441-451, 2006). MLL rearrangements are usually evident as overt balanced chromosomal translocations by conventional cytogenetic analysis but up to one-third are cryptic rearrangements and occur in leukemias with del(11)(q23), a normal karyotype, or trisomy 11, the latter two of which sometimes are associated with partial tandem duplications of MLL itself (Proc Natl Acad Sci USA 97:2814-2819, 2000; Proc Natl Acad Sci USA 94:3899-3902, 1997). In addition, subsets of MLL rearrangements are complex at a cytogenetic level and/or molecular level, and fuse MLL with two different partner genes. Rapid and accurate methods to identify and characterize genomic breakpoint junctions and fusion transcripts resulting from the many types of MLL rearrangements are essential for risk group stratification, treatment protocol assignments, new partner gene discovery, understanding leukemia etiology and pathogenesis, and elucidating the impact of less common MLL-partner genes on biology and prognosis. Due to the vast heterogeneity in partner genes, typical gene-specific PCR based methods are not practical, especially when cytogenetics are normal or do not suggest involvement of a known partner gene of MLL. We have advanced seven different panhandle PCR based methods for cloning 5'-MLL-partner gene-3' and 5'-partner gene-MLL-3' genomic breakpoint junctions and identifying 5'-MLL-partner gene-3' fusion transcripts, all of which employ a stem-loop template shaped schematically like a pan with a handle and amplify the template without knowledge of the unknown partner sequence using primers all derived from MLL alone.
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Archangelo LF, Greif PA, Hölzel M, Harasim T, Kremmer E, Przemeck GKH, Eick D, Deshpande AJ, Buske C, de Angelis MH, Saad STO, Bohlander SK. The CALM and CALM/AF10 interactor CATS is a marker for proliferation. Mol Oncol 2008; 2:356-67. [PMID: 19383357 DOI: 10.1016/j.molonc.2008.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 08/26/2008] [Accepted: 08/27/2008] [Indexed: 01/05/2023] Open
Abstract
The CATS protein was recently identified as a novel CALM interacting protein. CATS increases the nuclear and specifically the nucleolar localization of the leukemogenic CALM/AF10 fusion protein. We cloned and characterized the murine Cats gene. Detailed analysis of murine Cats expression during mouse embryogenesis showed an association with rapidly proliferating tissues. Interestingly, the Cats transcript is highly expressed in murine hematopoietic cells transformed by CALM/AF10. The CATS protein is highly expressed in leukemia, lymphoma and tumor cell lines but not in non-proliferating T-cells or human peripheral blood lymphocytes. CATS protein levels are cell cycle dependent and it is induced by mitogens, suggesting a role of CATS in the control of cell proliferation and possibly CALM/AF10-mediated leukemogenesis.
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Affiliation(s)
- Leticia Fröhlich Archangelo
- Department of Medicine III, University of Munich Hospital Grosshadern, German Research Center for Environmental Health, Munich, Germany
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21
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Maldonado-Báez L, Dores MR, Perkins EM, Drivas TG, Hicke L, Wendland B. Interaction between Epsin/Yap180 adaptors and the scaffolds Ede1/Pan1 is required for endocytosis. Mol Biol Cell 2008; 19:2936-48. [PMID: 18448668 PMCID: PMC2441688 DOI: 10.1091/mbc.e07-10-1019] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 04/16/2008] [Accepted: 04/22/2008] [Indexed: 01/08/2023] Open
Abstract
The spatial and temporal regulation of the interactions among the approximately 60 proteins required for endocytosis is under active investigation in many laboratories. We have identified the interaction between monomeric clathrin adaptors and endocytic scaffold proteins as a critical prerequisite for the recruitment and/or spatiotemporal dynamics of endocytic proteins at early and late stages of internalization. Quadruple deletion yeast cells (DeltaDeltaDeltaDelta) lacking four putative adaptors, Ent1/2 and Yap1801/2 (homologues of epsin and AP180/CALM proteins), with a plasmid encoding Ent1 or Yap1802 mutants, have defects in endocytosis and growth at 37 degrees C. Live-cell imaging revealed that the dynamics of the early- and late-acting scaffold proteins Ede1 and Pan1, respectively, depend upon adaptor interactions mediated by adaptor asparagine-proline-phenylalanine motifs binding to scaffold Eps15 homology domains. These results suggest that adaptor/scaffold interactions regulate transitions from early to late events and that clathrin adaptor/scaffold protein interaction is essential for clathrin-mediated endocytosis.
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Affiliation(s)
| | - Michael R. Dores
- Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, IL 60208
| | - Edward M. Perkins
- Integrated Imaging Center, The Johns Hopkins University, Baltimore, MD 21218; and
| | | | - Linda Hicke
- Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, IL 60208
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22
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A map of human protein interactions derived from co-expression of human mRNAs and their orthologs. Mol Syst Biol 2008; 4:180. [PMID: 18414481 PMCID: PMC2387231 DOI: 10.1038/msb.2008.19] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Accepted: 02/20/2008] [Indexed: 01/19/2023] Open
Abstract
The human protein interaction network will offer global insights into the molecular organization of cells and provide a framework for modeling human disease, but the network's large scale demands new approaches. We report a set of 7000 physical associations among human proteins inferred from indirect evidence: the comparison of human mRNA co-expression patterns with those of orthologous genes in five other eukaryotes, which we demonstrate identifies proteins in the same physical complexes. To evaluate the accuracy of the predicted physical associations, we apply quantitative mass spectrometry shotgun proteomics to measure elution profiles of 3013 human proteins during native biochemical fractionation, demonstrating systematically that putative interaction partners tend to co-sediment. We further validate uncharacterized proteins implicated by the associations in ribosome biogenesis, including WBSCR20C, associated with Williams-Beuren syndrome. This meta-analysis therefore exploits non-protein-based data, but successfully predicts associations, including 5589 novel human physical protein associations, with measured accuracies of 54+/-10%, comparable to direct large-scale interaction assays. The new associations' derivation from conserved in vivo phenomena argues strongly for their biological relevance.
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Abstract
Chromosomal translocations are important genetic perturbations frequently associated with hematologic malignancies; characterization of these events has been a rich source of insights into the mechanisms that lead to malignant transformation. The t(10;11)(p13;q14-21) results in a recently identified rare but recurring chromosomal translocation seen in patients with ALL as well as AML, and results in the production of a CALM-AF10 fusion gene. Although the details by which the CALM-AF10 fusion protein exerts its leukemogenic effect remain unclear, emerging data suggests that the CALM-AF10 fusion impairs differentiation of hematopoietic cells, at least in part via an upregulation of HOXA cluster genes. This review discusses the normal structure and function of CALM and AF10, describes the spectrum of clinical findings seen in patients with CALM-AF10 fusions, summarizes recently published CALM-AF10 mouse models and highlights the role of HOXA cluster gene activation in CALM-AF10 leukemia.
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Affiliation(s)
- D Caudell
- Genetics Branch, National Cancer Institute, National Institutes for Health, Bethesda, MD 20889-5105, USA
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24
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Pilecka I, Banach-Orlowska M, Miaczynska M. Nuclear functions of endocytic proteins. Eur J Cell Biol 2007; 86:533-47. [PMID: 17583371 DOI: 10.1016/j.ejcb.2007.04.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Revised: 04/19/2007] [Accepted: 04/19/2007] [Indexed: 01/14/2023] Open
Abstract
An increasing number of proteins appear to perform multiple, sometimes unrelated functions in the cell. Such moonlighting properties have been recently demonstrated for proteins involved in clathrin-mediated endocytosis. Some clathrin adaptors and endosomal proteins can undergo nucleocytoplasmic shuttling, which is often based on intrinsic sequence motifs and requires active transport mechanisms. Endocytic proteins can associate with nuclear molecules, changing their localization and/or activity and may modulate the levels and specificity of gene transcription. It is not clear how the nuclear and cytoplasmic pools of endocytic proteins are interconnected, or whether these molecules act as nuclear second messengers upon extracellular stimuli, but alike in endocytosis, they seem to form multi-component scaffolding platforms in the nucleus. Added to their endocytic functions, the nuclear roles of Eps15, Epsin1, CALM, HIP1, Dab1/2, beta-arrestins, APPL1/2 and the components of ESCRTs clearly increase the complexity of signaling networks affecting cellular growth, proliferation and homeostasis.
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Affiliation(s)
- Iwona Pilecka
- International Institute of Molecular and Cell Biology, Laboratory of Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland
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25
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Robinson BW, Slater DJ, Felix CA. BglII-based panhandle and reverse panhandle PCR approaches increase capability for cloning der(II) and der(other) genomic breakpoint junctions ofMLL translocations. Genes Chromosomes Cancer 2006; 45:740-53. [PMID: 16703585 DOI: 10.1002/gcc.20336] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Panhandle PCR techniques to amplify known sequence flanked by unknown sequence have been useful for MLL genomic breakpoint junctions and fusion transcripts because MLL has a large number of partner genes. However, genomic panhandle PCR approaches are impeded when the restriction fragment that contains the breakpoint junction is too large to amplify. We devised new panhandle PCR approaches for MLL genomic breakpoint junctions that create the template from BglII restriction fragments by attaching MLL sequence to a BglII site in the partner gene. This leads to the annealing of MLL and its complement in the handle and creates an intrastrand loop containing the breakpoint junction sequence for amplification with primers all from MLL. BglII panhandle PCR for der(11) breakpoint junctions was accomplished by ligating a phosphorylated oligonucleotide containing a BglII overhang and sequence complementary to MLL exon 7 to the 3' ends of BglII digested DNA, and forming the template from the sense strand of DNA. In BglII reverse panhandle PCR for der(other) breakpoint junctions, a phosphorylated oligonucleotide containing a BglII overhang and the complement of antisense sequence in MLL exon 10 was ligated to the 3' ends of BglII digested DNA, and the template was formed from the antisense strand of DNA. These approaches amplified 5'-MLL-MLLT4-3' and 5'-AFF1-MLL-3' breakpoint junctions. The former is significant because few t(6;11) genomic breakpoint junctions have been sequenced. BglII panhandle PCR approaches increase the possibilities for cloning MLL genomic breakpoint junctions where there is heterogeneity in partner genes and breakpoint locations.
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MESH Headings
- Adolescent
- Bacterial Proteins
- Base Sequence
- Chromosome Breakage
- Chromosomes, Human, Pair 11
- Chromosomes, Human, Pair 4
- Chromosomes, Human, Pair 6
- Cloning, Molecular/methods
- Deoxyribonucleases, Type II Site-Specific
- Humans
- Models, Biological
- Models, Genetic
- Molecular Sequence Data
- Myeloid-Lymphoid Leukemia Protein/genetics
- Myeloid-Lymphoid Leukemia Protein/metabolism
- Polymerase Chain Reaction/methods
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism
- Translocation, Genetic
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Affiliation(s)
- Blaine W Robinson
- Division of Oncology, The Children's Hospital of Philadelphia, PA 19104, USA
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26
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Dik WA, Brahim W, Braun C, Asnafi V, Dastugue N, Bernard OA, van Dongen JJM, Langerak AW, Macintyre EA, Delabesse E. CALM-AF10+ T-ALL expression profiles are characterized by overexpression of HOXA and BMI1 oncogenes. Leukemia 2005; 19:1948-57. [PMID: 16107895 DOI: 10.1038/sj.leu.2403891] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The t(10;11)(p13;q14-21) is found in T-ALL and acute myeloid leukemia and fuses CALM (Clathrin-Assembly protein-like Lymphoid-Myeloid leukaemia gene) to AF10. In order to gain insight into the transcriptional consequences of this fusion, microarray-based comparison of CALM-AF10+ vs CALM-AF10- T-ALL was performed. This analysis showed upregulation of HOXA5, HOXA9, HOXA10 and BMI1 in the CALM-AF10+ cases. Microarray results were validated by quantitative RT-PCR on an independent group of T-ALL and compared to mixed lineage leukemia-translocated acute leukemias (MLL-t AL). The overexpression of HOXA genes was associated with overexpression of its cofactor MEIS1 in CALM-AF10+ T-ALL, reaching levels of expression similar to those observed in MLL-t AL. Consequently, CALM-AF10+ T-ALL and MLL-t AL share a specific HOXA overexpression, indicating they activate common oncogenic pathways. In addition, BMI1, located close to AF10 breakpoint, was overexpressed only in CALM-AF10+ T-ALL and not in MLL-t AL. BMI1 controls cellular proliferation through suppression of the tumor suppressors encoded by the CDKN2A locus. This locus, often deleted in T-ALL, was conserved in CALM-AF10+ T-ALL. This suggests that decreased CDKN2A activity, as a result of BMI1 overexpression, contributes to leukemogenesis in CALM-AF10+ T-ALL. We propose to define a HOXA+ leukemia group composed of at least MLL-t, CALM-AF10 and HOXA-t AL, which may benefit from adapted management.
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Affiliation(s)
- W A Dik
- Department of Immunology, Erasmus MC, Rotterdam, The Netherlands
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27
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Colin M, Mailly L, Rogée S, D'Halluin JC. Efficient species C HAdV infectivity in plasmocytic cell lines using a clathrin-independent lipid raft/caveola endocytic route. Mol Ther 2005; 11:224-36. [PMID: 15668134 DOI: 10.1016/j.ymthe.2004.10.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2004] [Accepted: 10/05/2004] [Indexed: 10/26/2022] Open
Abstract
Hematopoietic cells are known to be refractory to species C human adenovirus (HAdV) infection; however, the reason for this has not been clearly established. We have previously demonstrated that this nonpermissivity is the consequence of inefficient HAdV particle uptake, notably in B lymphocytes. We noted that while the protein clathrin is observed in association with membranes in epithelial cells, it is found predominantly in the cytoplasm of hematopoietic cell lines. So it appears that altered clathrin-coated pit endocytosis could explain the weak HAdV uptake in B cells. In contrast, mature B cell plasmocytes are permissive to HAdV. However, this is not the result of clathrin-coated pit endocytosis since this process is also inefficient in these cells. Confocal microscopy showed colocalization between HAdV particles and caveolae/lipid rafts in plasmocytes. Moreover, inhibiting caveola endocytosis by depletion of cholesterol or expression of dominant negative caveolin-1 in these cells results in a 50-70% reduction in HAdV infectivity. It appears that caveola endocytosis and nonclathrin noncaveola endocytosis are used by HAdV to enter plasmocytes in response to a loss of the clathrin-dependent pathway. Thus targeting of caveolae by modifying the capsid of HAdV may represent an alternative approach to enhancing uptake in most hematopoietic cells for future gene therapy.
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Affiliation(s)
- Morvane Colin
- INSERM U524, IMPRT, Institut de Recherches sur le Cancer de Lille, 1 place de Verdun, 59045 Lille Cedex, France
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28
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Abstract
The receptor for hepatocyte growth factor (HGF), Met, controls a programme of invasive growth that combines proliferation with various moto- and morphogenetic processes. This process is important for development and organ regeneration, but dysregulation in transformed tissues can contribute to cancer progression and metastasis. Acute stimulation of tissue culture cells with HGF leads to Met downregulation via degradation through an endocytic mechanism that also requires proteasome activity. Perturbation of Met trafficking on the endocytic pathway, either at the level of the internalisation step or during sorting at the early endosome, leads to altered signalling outputs. Ubiquitination of Met through the E3-ligase Cbl is required for receptor downregulation, and a mutant receptor defective in Cbl binding is able to transform cells. We discuss the hypothesis that some naturally occurring Met mutants implicated in cancer may transform cells owing to defects in their trafficking along the endosomal degradation pathway.
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Affiliation(s)
- D E Hammond
- Physiological Laboratory, University of Liverpool, Liverpool, UK
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29
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Toubai T, Tanaka J, Higa T, Ota S, Ibata M, Shono Y, Mashiko S, Miura Y, Umehara S, Kahata K, Toyoshima N, Morioka M, Asaka M, Kasai M, Imamura M. Long-term follow-up of a patient with idiopathic myelofibrosis associated with chromosome 11 and 13 abnormalities. Am J Hematol 2005; 78:67-70. [PMID: 15609290 DOI: 10.1002/ajh.20254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A case of a leukemic transformation following a 27-year history of idiopathic myelofibrosis (IMF) is presented. The patient had two chromosomal abnormalities: a deletion of chromosome 13, del 13(q12q14), and a deletion of chromosome 11, del 11(q14q23). This patient's final diagnosis was acute micromegakaryocytic leukemia, and she died 1 month after leukemic transformation with an additional chromosomal abnormality, trisomy 8. IMF with myeloid metaplasia associated with deletion of the long arms of chromosomes 11 and 13 has not been previously reported. We speculate that the leukemic transformation in this patient was associated with chromosomal abnormalities del 11 and trisomy 8.
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Affiliation(s)
- Tomomi Toubai
- Department of Hematology and Oncology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
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Abstract
During recent years, alterations in proteins of the endocytic pathway have been associated with tumors. Disrupted regulation of the endocytic pathway is a relatively unstudied mechanism of tumorigenesis, which can concomitantly disrupt several different signaling pathways to affect growth, differentiation and survival. Several endocytic proteins have been identified, either as part of tumor-associated translocations or to have the ability to transform cells. Here, we summarize the information known about huntingtin interacting protein 1 (HIP1), an endocytic protein with transforming properties that is involved in a cancer-causing translocation and which is overexpressed in a variety of human cancers. We describe the known normal functions of HIP1 in endocytosis and receptor trafficking, the evidence for its role as an oncoprotein and how HIP1 might be altered to promote tumorigenesis.
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Affiliation(s)
- Teresa S Hyun
- Department of Internal Medicine and Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Mitterbauer-Hohendanner G, Mannhalter C. The biological and clinical significance of MLL abnormalities in haematological malignancies. Eur J Clin Invest 2004; 34 Suppl 2:12-24. [PMID: 15291802 DOI: 10.1111/j.0960-135x.2004.01366.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The MLL (Mixed Lineage Leukaemia or Myeloid/Lymphoid Leukaemia) gene on chromosome 11q23 is frequently involved in chromosomal translocations associated with human acute leukaemias. These translocations lead to fusion genes generally resulting in novel chimeric proteins containing the amino terminus of MLL fused in-frame to one of about 30 distinct partner proteins. Abnormalities involving the MLL gene are observed in leukaemias of either lymphoid or myeloid lineage derivation, as well as in poorly differentiated or biphenotypic leukaemias. They are frequently seen in infant patients, and patients with therapy-related secondary AML following treatment with inhibitors of topoisomerase II (epipodophyllotoxins). In the majority of cases, abnormalities involving the MLL gene are associated with a very poor prognostic outcome. In this review, we will discuss some of the recent advances in MLL research resulting from biological as well as clinical studies.
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Affiliation(s)
- G Mitterbauer-Hohendanner
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University Vienna, Austria.
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32
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Jones LK, Neat MJ, van Delft FW, Mitchell MP, Adamaki M, Stoneham SJ, Patel N, Saha V. Cryptic rearrangement involving MLL and AF10 occurring in utero. Leukemia 2003; 17:1667-9. [PMID: 12886258 DOI: 10.1038/sj.leu.2403039] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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