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Steinhart J, Möller P, Kull M, Krönke J, Barth TFE. CDK6 protein expression is associated with disease progression and treatment resistance in multiple myeloma. Hemasphere 2024; 8:e32. [PMID: 38434534 PMCID: PMC10878183 DOI: 10.1002/hem3.32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 11/13/2023] [Indexed: 03/05/2024] Open
Abstract
Multiple myeloma (MM) is a heterogeneous malignancy of plasma cells. Despite improvement in the prognosis of MM patients after the introduction of many new drugs in the past decades, MM remains incurable since most patients become treatment-resistant. Cyclin-dependent kinase 6 (CDK6) is activated in many types of cancer and has been associated with drug resistance in MM. However, its association with disease stage, genetic alterations, and outcome has not been systematically investigated in large cohorts. Here, we analyzed CDK6 expression using immunohistochemistry in 203 formalin-fixed paraffin-embedded samples of 146 patients and four healthy individuals. We found that 61.5% of all MM specimens express CDK6 at various levels. CDK6 expression increased with the progression of disease with a median of 0% of CDK6-positive plasma cells in monoclonal gammopathy of undetermined significance (MGUS) (n = 10) to 30% in newly diagnosed MM (n = 78) and up to 70% in relapsed cases (n = 55). The highest median CDK6 was observed in extramedullary myeloma (n = 12), a highly aggressive manifestation of MM. Longitudinal analyses revealed that CDK6 is significantly increased in lenalidomide-treated patients but not in those who did not receive lenalidomide. Furthermore, we observed that patients who underwent lenalidomide-comprising induction therapy had significantly shorter progression-free survival when their samples were CDK6 positive. These data support that CDK6 protein expression is a marker for aggressive and drug-resistant disease and describes a potential drug target in MM.
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Affiliation(s)
- Johannes Steinhart
- Department of PathologyUlm University HospitalUlmGermany
- Department of Internal Medicine IIIUlm University HospitalUlmGermany
| | - Peter Möller
- Department of PathologyUlm University HospitalUlmGermany
| | - Miriam Kull
- Department of Internal Medicine IIIUlm University HospitalUlmGermany
| | - Jan Krönke
- Department of Internal Medicine IIIUlm University HospitalUlmGermany
- Department of Hematology, Oncology and Cancer Immunology, Charité ‐ Universitätsmedizin Berlincorporate member of Freie Universität Berlin and Humboldt‐Universität zu BerlinBerlinGermany
- German Cancer Consortium (DKTK) partner site Berlin and German Cancer Research Center (DKFZ)HeidelbergGermany
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2
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Rafatpanah H, Golizadeh M, Mahdifar M, Mahdavi S, Iranshahi M, Rassouli FB. Conferone, a coumarin from Ferula flabelliloba, induced toxic effects on adult T-cell leukemia/lymphoma cells. Int J Immunopathol Pharmacol 2023; 37:3946320231197592. [PMID: 37688389 PMCID: PMC10493046 DOI: 10.1177/03946320231197592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/10/2023] Open
Abstract
BACKGROUND Adult T-cell leukemia/lymphoma (ATL) is a lymphoid malignancy caused by HTLV-1 infection, with distinct geographical distribution. Despite advances in cancer treatment, the average survival rate of ATL is low. Conferone is a natural coumarin extracted from Ferula species with a wide range of pharmaceutical effects. In search for a novel chemotherapeutic agent, we investigated the cytotoxicity of conferone on ATL cells. METHODS To obtain conferone, the methanolic extract of the roots of F. flabelliloba was subjected to silica gel column chromatography, followed by 1H- and 13C-NMR to confirm its structure. For cytotoxicity assay, MT-2 cells were treated with different concentrations of conferone (2.5, 5, 10, 20, and 40 µM) for 24, 48, and 72 h, and viability was evaluated by a colorimetric assay using alamarBlue. Cell cycle was analyzed by PI staining and flow cytometry, and qPCR was used to study the expression of candidate genes. RESULTS AND CONCLUSION Obtained findings indicated that conferone induced considerable cytotoxic effects on MT-2 cells in a time- and dose-dependent manner. In addition, accumulation of cells in the sub-G1 phase of the cell cycle was detected upon conferone administration. Moreover, conferone reduced the expression of CDK6, c-MYC, CFLIPL, and NF-κB (Rel-A) in MT-2 cells. Accordingly, conferone could be considered as a potent agent against ATL, although complementary investigations are required to define more precisely its mechanism of action.
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Affiliation(s)
- Houshang Rafatpanah
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Marziyeh Golizadeh
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Maryam Mahdifar
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shakiba Mahdavi
- Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Mehrdad Iranshahi
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Fatemeh B Rassouli
- Novel Diagnostics and Therapeutics Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
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3
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Baker SJ, Poulikakos PI, Irie HY, Parekh S, Reddy EP. CDK4: a master regulator of the cell cycle and its role in cancer. Genes Cancer 2022; 13:21-45. [PMID: 36051751 PMCID: PMC9426627 DOI: 10.18632/genesandcancer.221] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 08/17/2022] [Indexed: 11/25/2022] Open
Abstract
The cell cycle is regulated in part by cyclins and their associated serine/threonine cyclin-dependent kinases, or CDKs. CDK4, in conjunction with the D-type cyclins, mediates progression through the G1 phase when the cell prepares to initiate DNA synthesis. Although Cdk4-null mutant mice are viable and cell proliferation is not significantly affected in vitro due to compensatory roles played by other CDKs, this gene plays a key role in mammalian development and cancer. This review discusses the role that CDK4 plays in cell cycle control, normal development and tumorigenesis as well as the current status and utility of approved small molecule CDK4/6 inhibitors that are currently being used as cancer therapeutics.
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Affiliation(s)
- Stacey J. Baker
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
| | - Poulikos I. Poulikakos
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
| | - Hanna Y. Irie
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
- Department of Hematology and Medical Oncology, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
| | - Samir Parekh
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
- Department of Hematology and Medical Oncology, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
| | - E. Premkumar Reddy
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, Levy Place, NY 10029, USA
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4
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Tang YF, Wu WJ, Zhang JY, Zhang J. Reconstruction and analysis of the aberrant lncRNA-miRNA-mRNA network based on competitive endogenous RNA in adenoid cystic carcinoma of the salivary gland. Transl Cancer Res 2022; 10:5133-5149. [PMID: 35116364 PMCID: PMC8798187 DOI: 10.21037/tcr-21-1771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 11/18/2021] [Indexed: 11/06/2022]
Abstract
Background The aim of this work was to investigate the competing endogenous RNA (ceRNA) network in adenoid cystic carcinoma of the salivary gland (SACC). Methods Differentially expressed lncRNAs (DElncRNAs), miRNAs (DEmiRNAs), and mRNAs (DEmRNAs) between cancer tissues and normal salivary gland (NSG) in ACC were identified using data from the Gene Expression Omnibus (GEO) database. Functional annotation and pathway enrichment analysis of DEmRNAs were performed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. The miRNAs that are targeted by lncRNAs were predicted using miRanda and PITA, while the target mRNAs of miRNAs were retrieved from miRanda, miRWalk, and TargetScan. A protein-protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, and then we constructed the lncRNA-miRNA-mRNA networks of ACC. Results Differentially expressed RNAs were identified in SACC. Upon comparing cancer tissues and NSG tissues, 103 upregulated and 52 downregulated lncRNAs and 745 upregulated and 866 downregulated mRNAs were identified in GSE88804; in addition, 39 upregulated and 43 downregulated miRNAs were identified in GSE117275. GO enrichment analyses revealed that the most relevant GO terms were regulation of transcription DNA-templated, transcription DNA-templated, and cell division. KEGG pathway enrichment analysis showed that differentially expressed genes (DEGs) were mainly enriched in the cell cycle, pathways in cancer, PI3K-Akt signaling pathway, breast cancer, and microRNAs in cancer. The PPI network consisted of 27 upregulated and 54 downregulated mRNAs. By constructing ceRNA network, NONHSAT251752.1-hsa-miR-6817-5p-NOTCH1, NONHSAT251752.1-hsa-miR-204-5p/hsa-miR-138-5p-CDK6 regulatory axises were identified and all genes in the network were verified by qRT-PCR. Conclusions The present study constructed ceRNA networks in SACC and provided a novel perspective of the molecular mechanisms for SACC.
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Affiliation(s)
- Yu-Fang Tang
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.,National Center of Stomatology & National Clinical Research Center for Oral Diseases, Beijing, China.,Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, China
| | - Wen-Jie Wu
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.,National Center of Stomatology & National Clinical Research Center for Oral Diseases, Beijing, China.,Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, China
| | - Jian-Yun Zhang
- National Center of Stomatology & National Clinical Research Center for Oral Diseases, Beijing, China.,Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, China.,Department of Oral Pathology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Jie Zhang
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.,National Center of Stomatology & National Clinical Research Center for Oral Diseases, Beijing, China.,Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, China
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5
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Gailllard B, Cornillet-Lefebvre P, Le QH, Maloum K, Pannetier M, Lecoq-Lafon C, Grange B, Jondreville L, Michaux L, Nadal N, Ittel A, Luquet I, Struski S, Lefebvre C, Gaillard JB, Lafage-Pochitaloff M, Balducci E, Penther D, Barin C, Collonge-Rame MA, Jimenez-Poquet M, Richebourg S, Lemaire P, Defasque S, Radford-Weiss I, Bidet A, Susin SA, Nguyen-Khac F, Chapiro E. Clinical and biological features of B-cell neoplasms with CDK6 translocations: an association with a subgroup of splenic marginal zone lymphomas displaying frequent CD5 expression, prolymphocytic cells, and TP53 abnormalities. Br J Haematol 2020; 193:72-82. [PMID: 33314017 DOI: 10.1111/bjh.17141] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/04/2020] [Accepted: 09/09/2020] [Indexed: 01/16/2023]
Abstract
A translocation involving the cyclin-dependent kinase 6 (CDK6) gene [t(CDK6)] is a rare but recurrent abnormality in B-cell neoplasms. To further characterise this aberration, we studied 57 cases; the largest series reported to date. Fluorescence in situ hybridisation analysis confirmed the involvement of CDK6 in all cases, including t(2;7)(p11;q21) immunoglobulin kappa locus (IGK)/CDK6 (n = 51), t(7;14)(q21;q32) CDK6/immunoglobulin heavy locus (IGH) (n = 2) and the previously undescribed t(7;14)(q21;q11) CDK6/T-cell receptor alpha locus (TRA)/T-cell receptor delta locus (TRD) (n = 4). In total, 10 patients were diagnosed with chronic lymphocytic leukaemia, monoclonal B-cell lymphocytosis or small lymphocytic lymphoma, and 47 had small B-cell lymphoma (SmBL) including 36 cases of marginal zone lymphoma (MZL; 34 splenic MZLs, one nodal MZL and one bronchus-associated lymphoid tissue lymphoma). In all, 18 of the 26 cytologically reviewed cases of MZL (69%) had an atypical aspect with prolymphocytic cells. Among the 47 patients with MZL/SmBL, CD5 expression was found in 26 (55%) and the tumour protein p53 (TP53) deletion in 22 (47%). The TP53 gene was mutated in 10/30 (33%); the 7q deletion was detected in only one case, and no Notch receptor 2 (NOTCH2) mutations were found. Immunoglobulin heavy-chain variable-region (IGHV) locus sequencing revealed that none harboured an IGHV1-02*04 gene. Overall survival was 82% at 10 years and not influenced by TP53 aberration. Our present findings suggest that most t(CDK6)+ neoplasms correspond to a particular subgroup of indolent marginal zone B-cell lymphomas with distinctive features.
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Affiliation(s)
| | | | - Quoc-Hung Le
- Service d'Hématologie Clinique, Hôpital Robert Debré, Reims, France
| | - Karim Maloum
- Service d'Hématologie Biologique, Hôpital Pitié-Salpêtrière, Assistance Publique - Hôpitaux de Paris (APHP), Paris, France
| | - Mélanie Pannetier
- Laboratoire d'Hématologie, Centre Hospitalo-Universitaire, Rennes, France
| | | | - Béatrice Grange
- Service d'Hématologie Biologique, Hospices Civils de Lyon, Lyon, France
| | - Ludovic Jondreville
- Centre de Recherche des Cordeliers, INSERM UMRS_1138, Cell Death and Drug Resistance in Lymphoproliferative Disorders Team, Paris, France
| | - Lucienne Michaux
- Center for Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - Nathalie Nadal
- Service de génétique chromosomique et moléculaire, CHU Dijon, France
| | - Antoine Ittel
- Laboratoire de Cytogénétique Hématologique, CHU de Strasbourg, Strasbourg, France
| | - Isabelle Luquet
- Laboratoire d'Hématologie, Institut Universitaire du Cancer de Toulouse, Toulouse, France
| | - Stéphanie Struski
- Laboratoire d'Hématologie, Institut Universitaire du Cancer de Toulouse, Toulouse, France
| | | | | | - Marina Lafage-Pochitaloff
- Laboratoire de Cytogénétique Onco-Hématologique, Hôpital de la Timone, AP-HM, Aix-Marseille Université, Marseille, France
| | - Estelle Balducci
- Laboratoire d'Hématologie, Hôpital Paul Brousse, APHP, Villejuif, France
| | - Dominique Penther
- Laboratoire de Génétique Oncologique, CLCC Henri Becquerel and INSERM U1245, Rouen, France
| | - Carole Barin
- Laboratoire de Cytogénétique hématologique, Service de Génétique, CHRU Bretonneau, Tours, France
| | | | | | - Steven Richebourg
- Laboratoire de Cytogénétique Onco-Hématologique, CHU de Québec - Université Laval, Québec, Canada
| | - Pierre Lemaire
- Laboratoire d'Hématologie, Hôpital Saint-Louis, APHP, Paris, France
| | - Sabine Defasque
- Secteur cytogénétique hématologique, Laboratoire CERBA, Saint-Ouen l'Aumône, France
| | | | - Audrey Bidet
- Laboratoire d'Hématologie, CHU Bordeaux-Haut Lévêque, Bordeaux, France
| | - Santos A Susin
- Centre de Recherche des Cordeliers, INSERM UMRS_1138, Cell Death and Drug Resistance in Lymphoproliferative Disorders Team, Paris, France.,Sorbonne Université, Paris, France
| | - Florence Nguyen-Khac
- Service d'Hématologie Biologique, Hôpital Pitié-Salpêtrière, Assistance Publique - Hôpitaux de Paris (APHP), Paris, France.,Centre de Recherche des Cordeliers, INSERM UMRS_1138, Cell Death and Drug Resistance in Lymphoproliferative Disorders Team, Paris, France.,Sorbonne Université, Paris, France
| | - Elise Chapiro
- Service d'Hématologie Biologique, Hôpital Pitié-Salpêtrière, Assistance Publique - Hôpitaux de Paris (APHP), Paris, France.,Centre de Recherche des Cordeliers, INSERM UMRS_1138, Cell Death and Drug Resistance in Lymphoproliferative Disorders Team, Paris, France.,Sorbonne Université, Paris, France
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Shah SI, D’Angelo CR, Kratz JD, Yang DT. Diagnostic challenges in an aggressive case of peripheralizing marginal zone lymphoma. Clin Case Rep 2020; 8:3303-3310. [PMID: 33363923 PMCID: PMC7752602 DOI: 10.1002/ccr3.3395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/07/2020] [Accepted: 08/29/2020] [Indexed: 12/19/2022] Open
Abstract
B-cell lymphomas with atypical presentation or immunophenotype pose diagnostic challenges. Conventional ancillary tests (cytogenetics, FISH) can help, but have technical limitations. New technologies such as mate-pair sequencing (MPSeq) offer a route around these technical limitations.
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Affiliation(s)
- Sujal I. Shah
- Department of PathologyUniversity of Wisconsin School of Medicine and Public HealthMadisonWIUSA
| | - Christopher R. D’Angelo
- Department of MedicineSection of Hematology/OncologyUniversity of Wisconsin School of Medicine and Public HealthMadisonWIUSA
| | - Jeremy D. Kratz
- Department of MedicineSection of Hematology/OncologyUniversity of Wisconsin School of Medicine and Public HealthMadisonWIUSA
| | - David T. Yang
- Department of PathologyUniversity of Wisconsin School of Medicine and Public HealthMadisonWIUSA
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7
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Nebenfuehr S, Kollmann K, Sexl V. The role of CDK6 in cancer. Int J Cancer 2020; 147:2988-2995. [PMID: 32406095 PMCID: PMC7586846 DOI: 10.1002/ijc.33054] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/29/2020] [Accepted: 05/04/2020] [Indexed: 12/27/2022]
Abstract
The regulation and function of cyclin‐dependent kinase 6 (CDK6)‐ and cyclin‐dependent kinase 4 (CDK4)‐cyclin complexes are commonly altered with enhanced kinase activity found in hematopoietic malignancies, breast cancer and melanoma making CDK4 and CDK6 attractive targets for therapeutic interference. Although dual CDK4/6 inhibitors have revolutionized treatment of breast cancer patients and reveal promising results in several solid tumors and hematological malignancies, there is a need for novel compounds targeting the versatile kinase‐independent functions of CDK6 to improve cancer treatment. The following review summarizes the latest findings on CDK6 in cancer development and discusses novel therapeutic approaches to selectively inhibit CDK6s function as a transcriptional regulator.
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Affiliation(s)
- Sofie Nebenfuehr
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Karoline Kollmann
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Veronika Sexl
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, Vienna, Austria
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8
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Uras IZ, Sexl V, Kollmann K. CDK6 Inhibition: A Novel Approach in AML Management. Int J Mol Sci 2020; 21:ijms21072528. [PMID: 32260549 PMCID: PMC7178035 DOI: 10.3390/ijms21072528] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 03/29/2020] [Accepted: 04/02/2020] [Indexed: 02/01/2023] Open
Abstract
Acute myeloid leukemia (AML) is a complex disease with an aggressive clinical course and high mortality rate. The standard of care for patients has only changed minimally over the past 40 years. However, potentially useful agents have moved from bench to bedside with the potential to revolutionize therapeutic strategies. As such, cell-cycle inhibitors have been discussed as alternative treatment options for AML. In this review, we focus on cyclin-dependent kinase 6 (CDK6) emerging as a key molecule with distinct functions in different subsets of AML. CDK6 exerts its effects in a kinase-dependent and -independent manner which is of clinical significance as current inhibitors only target the enzymatic activity.
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Affiliation(s)
- Iris Z. Uras
- Department of Pharmacology, Center of Physiology and Pharmacology & Comprehensive Cancer Center (CCC), Medical University of Vienna, 1090 Vienna, Austria;
| | - Veronika Sexl
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, 1210 Vienna, Austria;
| | - Karoline Kollmann
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, 1210 Vienna, Austria;
- Correspondence: ; Tel.: + 43-1-25077-2917
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Abstract
The mammalian cell cycle is driven by a complex of cyclins and their associated cyclin-dependent kinases (CDKs). Abnormal dysregulation of cyclin-CDK is a hallmark of cancer. D-type cyclins and their associated CDKs (CDK4 and CDK6) are key components of cell cycle machinery in driving G1 to S phase transition via phosphorylating and inactivating the retinoblastoma protein (RB). A body of evidence shows that the cyclin Ds-CDKs axis plays a critical role in cancer through various aspects, such as control of proliferation, senescence, migration, apoptosis, and angiogenesis. CDK4/6 dual-inhibitors show significant efficacy in pre-clinical or clinical cancer therapies either as single agents or in combination with hormone, chemotherapy, irradiation or immune treatments. Of note, as the associated partner of D-type cyclins, CDK6 shows multiple distinct functions from CDK4 in cancer. Depletion of the individual CDK may provide a therapeutic strategy for patients with cancer.
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Affiliation(s)
- Xueliang Gao
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, United States
| | - Gustavo W Leone
- Department of Biochemistry & Molecular Biology, College of Medicine, Medical University of South Carolina, Charleston, SC, United States; Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
| | - Haizhen Wang
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, United States; Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States.
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Kim CY, Na K, Park S, Jeong SK, Cho JY, Shin H, Lee MJ, Han G, Paik YK. FusionPro, a Versatile Proteogenomic Tool for Identification of Novel Fusion Transcripts and Their Potential Translation Products in Cancer Cells. Mol Cell Proteomics 2019; 18:1651-1668. [PMID: 31208993 PMCID: PMC6683003 DOI: 10.1074/mcp.ra119.001456] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/23/2019] [Indexed: 01/21/2023] Open
Abstract
Fusion proteoforms are translation products derived from gene fusion. Although very rare, the fusion proteoforms play important roles in biomedical science. For example, fusion proteoforms influence the development of tumors by serving as cancer markers or cell cycle regulators. Although numerous studies have reported bioinformatics tools that can predict fusion transcripts, few proteogenomic tools are available that can predict and identify proteoforms. In this study, we develop a versatile proteogenomic tool "FusionPro," which facilitates the identification of fusion transcripts and their potential translatable peptides. FusionPro provides an independent gene fusion prediction module and can build sequence databases for annotated fusion proteoforms. FusionPro shows greater sensitivity than the available fusion finders when analyzing simulated or real RNA sequencing data sets. We use FusionPro to identify 18 fusion junction peptides and three potential fusion-derived peptides by MS/MS-based analysis of leukemia cell lines (Jurkat and K562) and ovarian cancer tissues from the Clinical Proteomic Tumor Analysis Consortium. Among the identified fusion proteins, we molecularly validate two fusion junction isoforms and a translation product of FAM133B:CDK6. Moreover, sequence analysis suggests that the fusion protein participates in the cell cycle progression. In addition, our prediction results indicate that fusion transcripts often have multiple fusion junctions and that these fusion junctions tend to be distributed in a nonrandom pattern at both the chromosome and gene levels. Thus, FusionPro allows users to detect various types of fusion translation products using a transcriptome-informed approach and to gain a comprehensive understanding of the formation and biological roles of fusion proteoforms.
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Affiliation(s)
- Chae-Yeon Kim
- ‡Interdisciplinary Program of Integrated OMICS for Biomedical Science, The Graduate School, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea; §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Keun Na
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Saeram Park
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Seul-Ki Jeong
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Jin-Young Cho
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Heon Shin
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Min Jung Lee
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Gyoonhee Han
- ¶Department of Pharmacy, College of Pharmacy, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Young-Ki Paik
- §Yonsei Proteome Research Center, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
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11
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CDK6 coordinates JAK2 V617F mutant MPN via NF-κB and apoptotic networks. Blood 2019; 133:1677-1690. [PMID: 30635286 DOI: 10.1182/blood-2018-08-872648] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 01/07/2019] [Indexed: 01/27/2023] Open
Abstract
Over 80% of patients with myeloproliferative neoplasms (MPNs) harbor the acquired somatic JAK2 V617F mutation. JAK inhibition is not curative and fails to induce a persistent response in most patients, illustrating the need for the development of novel therapeutic approaches. We describe a critical role for CDK6 in MPN evolution. The absence of Cdk6 ameliorates clinical symptoms and prolongs survival. The CDK6 protein interferes with 3 hallmarks of disease: besides regulating malignant stem cell quiescence, it promotes nuclear factor κB (NF-κB) signaling and contributes to cytokine production while inhibiting apoptosis. The effects are not mirrored by palbociclib, showing that the functions of CDK6 in MPN pathogenesis are largely kinase independent. Our findings thus provide a rationale for targeting CDK6 in MPN.
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Capela de Matos RR, Othman MAK, Ferreira GM, Costa ES, Melo JB, Carreira IM, de Souza MT, Lopes BA, Emerenciano M, Land MGP, Liehr T, Ribeiro RC, Silva MLM. Molecular approaches identify a cryptic MECOM rearrangement in a child with a rapidly progressive myeloid neoplasm. Cancer Genet 2018; 221:25-30. [PMID: 29405993 DOI: 10.1016/j.cancergen.2017.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 12/08/2017] [Accepted: 12/13/2017] [Indexed: 11/15/2022]
Abstract
Myeloid neoplasms are a heterogeneous group of hematologic disorders with divergent patterns of cell differentiation and proliferation, as well as divergent clinical courses. Rare recurrent genetic abnormalities related to this group of cancers are associated with poor outcomes. One such abnormality is the MECOM gene rearrangement that typically occurs in cases with chromosome 7 abnormalities. MECOM encodes a transcription factor that plays an essential role in cell proliferation and maintenance and also in epigenetic regulation. Aberrant expression of this gene is associated with reduced survival. Hence, its detailed characterization provides biological and clinical information relevant to the management of pediatric myeloid neoplasms. In this work, we describe a rare karyotype harboring three copies of MECOM with overexpression of the gene in a child with a very aggressive myeloid neoplasm. Cytogenetic studies defined the karyotype as 46,XX,der(7)t(3;7)(q26.2;q21.2). Array comparative genomic hybridization (aCGH) revealed a gain of 26.04 Mb in the 3q26.2-3qter region and a loss of 66.6 Mb in the 7q21.2-7qter region. RT-qPCR analysis detected elevated expression of the MECOM and CDK6 genes (458.5-fold and 35.2-fold, respectively). Overall, we show the importance of performing detailed molecular cytogenetic analysis of MECOM to enable appropriate management of high-risk pediatric myeloid neoplasms.
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Affiliation(s)
- Roberto R Capela de Matos
- Cytogenetics Department, Bone Marrow Transplantation Unit, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil; Post-Graduate Program in Oncology, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil
| | - Moneeb A K Othman
- Jena University Hospital, Institute of Human Genetics, Jena, Germany
| | - Gerson M Ferreira
- Stem Cells Department, Bone Marrow Transplantation Unit, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil
| | - Elaine S Costa
- Internal Medicine post-graduation program of Faculty of Medicine, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Joana B Melo
- Laboratory of Cytogenetics and Genomics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Isabel M Carreira
- Laboratory of Cytogenetics and Genomics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Mariana T de Souza
- Cytogenetics Department, Bone Marrow Transplantation Unit, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil; Post-Graduate Program in Oncology, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil
| | - Bruno A Lopes
- Post-Graduate Program in Oncology, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil; Pediatric Hematology-Oncology Program, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil
| | - Mariana Emerenciano
- Post-Graduate Program in Oncology, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil; Pediatric Hematology-Oncology Program, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil
| | - Marcelo G P Land
- Internal Medicine post-graduation program of Faculty of Medicine, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Thomas Liehr
- Jena University Hospital, Institute of Human Genetics, Jena, Germany
| | - Raul C Ribeiro
- Departments of Oncology and Global Medicine, St. Jude Children's Research Hospital, Memphis, Tennessee, USA; Instituto Pelé Pequeno Príncipe, Postgraduate Program in Child Adolescent Health, Curitiba, Paraná, Brazil
| | - Maria Luiza M Silva
- Cytogenetics Department, Bone Marrow Transplantation Unit, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil; Post-Graduate Program in Oncology, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA-RJ), Rio de Janeiro, Brazil; Internal Medicine post-graduation program of Faculty of Medicine, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
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13
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Mazzoccoli L, Robaina MC, Apa AG, Bonamino M, Pinto LW, Queiroga E, Bacchi CE, Klumb CE. MiR-29 silencing modulates the expression of target genes related to proliferation, apoptosis and methylation in Burkitt lymphoma cells. J Cancer Res Clin Oncol 2018; 144:483-497. [PMID: 29318382 DOI: 10.1007/s00432-017-2575-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 12/28/2017] [Indexed: 12/22/2022]
Abstract
PURPOSE Burkitt lymphoma (BL) is a B-cell lymphoma frequently diagnosed in children. It is characterized by MYC translocations, which lead to the constitutive expression of the MYC oncogene. MYC contributes to miR-29 repression through an E-box MYC binding site on the miR-29b-1/miR-29a promoter region. We evaluated the role of miR-29a/b/c and their predicted targets in BL pathogenesis. METHODS Mature sequences of miR-29a/b/c were transfected to the BL cell lines BL41 and Raji, and evaluated for DNMT3B, MCL1, BIM, CDK6, AKT and TCL1 protein expression as well as for MCL-1 and CDK6 mRNA expression. BL cells were treated with 5-aza-2'-deoxycytidine (decitabine) and evaluated for miR29 expressions and methylation status. DNMT3B inhibition was performed by DNMT3B siRNA. RESULTS Ectopic expression of miR-29s in BL cells decreased CDK6, DNMT3B, TCL1 and MCL-1 protein levels, but CDK6 and MCL-1 mRNA expression was unaffected by miR-29. Decitabine enhanced miR-29 expression levels and decreased CDK6 protein expression. Additionally, inhibition of DNMT3B by siRNA increased miR-29a/b expression. Notably, the miR-29a/b1 and miR-29b2/c promoter genes showed methylated CpG sequences that were demethylated after decitabine treatments. Furthermore, MYC-negative tumours had higher levels of miR-29 expression compared with MYC-translocated cases, suggesting that MYC regulates miR-29 in BL tumours. CONCLUSIONS Our results suggest a significant role for miR-29s in BL pathogenesis in altering the expression of targets involved in critical cancer pathways, such as cell cycle control, apoptosis inhibition and DNA methylation. Moreover, methylation-mediated miR-29 epigenetic silencing may occur during BL development.
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Affiliation(s)
- Luciano Mazzoccoli
- Programa de Pesquisa em Hemato-Oncologia Molecular, Instituto Nacional de Câncer, Rio de Janeiro, Brazil
| | - Marcela Cristina Robaina
- Programa de Pesquisa em Hemato-Oncologia Molecular, Instituto Nacional de Câncer, Rio de Janeiro, Brazil
| | | | - Martin Bonamino
- Programa de Carcinogênese Molecular, Instituto Nacional de Câncer, Rio de Janeiro, Brazil.,Fundação Instituto Oswaldo Cruz, Vice-presidência de Pesquisa e Laboratórios de Referência, Rio de Janeiro, Brazil
| | | | - Eduardo Queiroga
- Laboratório Bacchi, Consultoria em Patologia, Botucatu, São Paulo, Brazil
| | - Carlos E Bacchi
- Laboratório Bacchi, Consultoria em Patologia, Botucatu, São Paulo, Brazil
| | - Claudete Esteves Klumb
- Programa de Pesquisa em Hemato-Oncologia Molecular, Instituto Nacional de Câncer, Rio de Janeiro, Brazil. .,Laboratório de Hemato-Oncologia Celular e Molecular, Instituto Nacional de Câncer, Praça da Cruz Vermelha, 23, 6° andar, ala C, Rio de Janeiro, RJ, CEP: 20230-130, Brazil.
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14
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Jabbar SB, Monaghan S, Chen W, Koduru P, Kumar K. Acute Myeloid Leukemia With a Rare t(7;14)(q21;q32) and Trisomy 4 With Poor Clinical Outcome: A Case Report. Lab Med 2017; 48:376-380. [PMID: 29069512 DOI: 10.1093/labmed/lmx034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Objectives Recurrent cytogenetic abnormalities and/or molecular aberrations play an important role in the diagnosis and prognostification of acute myeloid leukemia (AML). We describe a case of a 40 year old woman diagnosed with de novo AML with a novel t(7;14)(q21,q32) and trisomy 4 with poor clinical outcome. Methods: Morphologic, flow cytometry and cytogenetic results of the patient's peripheral blood and bone marrow samples were analyzed. Results The diagnostic bone marrow was hypercellular for age (>95%) with increased blasts (62%) that by flow cytometry exhibited myeloid differentiation with a few T/NK lineage markers. Cytogenetics showed a t(7;14)(q21,q32) and trisomy 4. The patient had extremely poor response to two rounds of induction chemotherapy with persistent leukemia following therapy. Conclusion To the best of our knowledge, the t(7;14) is a novel cytogenetic abnormality that has not been reported previously in acute myeloid leukemia, and is important to report as it appears to be associated with poor prognosis.
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Affiliation(s)
- Seema B Jabbar
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Sara Monaghan
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Weina Chen
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Prasad Koduru
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Kirthi Kumar
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
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15
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Tao YF, Wang NN, Xu LX, Li ZH, Li XL, Xu YY, Fang F, Li M, Qian GH, Li YH, Li YP, Wu Y, Ren JL, Du WW, Lu J, Feng X, Wang J, He WQ, Hu SY, Pan J. Molecular mechanism of G 1 arrest and cellular senescence induced by LEE011, a novel CDK4/CDK6 inhibitor, in leukemia cells. Cancer Cell Int 2017; 17:35. [PMID: 28286417 PMCID: PMC5340031 DOI: 10.1186/s12935-017-0405-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 02/25/2017] [Indexed: 12/30/2022] Open
Abstract
Background Overexpression of cyclin D1 dependent kinases 4 and 6 (CDK4/6) is a common feature of many human cancers including leukemia. LEE011 is a novel inhibitor of both CDK4 and 6. To date, the molecular function of LEE011 in leukemia remains unclear. Methods Leukemia cell growth and apoptosis following LEE011 treatment was assessed through CCK-8 and annexin V/propidium iodide staining assays. Cell senescence was assessed by β-galactosidase staining and p16INK4a expression analysis. Gene expression profiles of LEE011 treated HL-60 cells were investigated using an Arraystar Human LncRNA array. Gene ontology and KEGG pathway analysis were then used to analyze the differentially expressed genes from the cluster analysis. Results Our studies demonstrated that LEE011 inhibited proliferation of leukemia cells and could induce apoptosis. Hoechst 33,342 staining analysis showed DNA fragmentation and distortion of nuclear structures following LEE011 treatment. Cell cycle analysis showed LEE011 significantly induced cell cycle G1 arrest in seven of eight acute leukemia cells lines, the exception being THP-1 cells. β-Galactosidase staining analysis and p16INK4a expression analysis showed that LEE011 treatment can induce cell senescence of leukemia cells. LncRNA microarray analysis showed 2083 differentially expressed mRNAs and 3224 differentially expressed lncRNAs in LEE011-treated HL-60 cells compared with controls. Molecular function analysis showed that LEE011 induced senescence in leukemia cells partially through downregulation of the transcriptional expression of MYBL2. Conclusions We demonstrate for the first time that LEE011 treatment results in inhibition of cell proliferation and induction of G1 arrest and cellular senescence in leukemia cells. LncRNA microarray analysis showed differentially expressed mRNAs and lncRNAs in LEE011-treated HL-60 cells and we demonstrated that LEE011 induces cellular senescence partially through downregulation of the expression of MYBL2. These results may open new lines of investigation regarding the molecular mechanism of LEE011 induced cellular senescence. Electronic supplementary material The online version of this article (doi:10.1186/s12935-017-0405-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yan-Fang Tao
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Na-Na Wang
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Li-Xiao Xu
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Zhi-Heng Li
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Xiao-Lu Li
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Yun-Yun Xu
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Fang Fang
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Mei Li
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Guang-Hui Qian
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Yan-Hong Li
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Yi-Ping Li
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Yi Wu
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Jun-Li Ren
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Wei-Wei Du
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Jun Lu
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Xing Feng
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Jian Wang
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
| | - Wei-Qi He
- CAM-SU Genomic Resource Center, Soochow University, Suzhou, China
| | - Shao-Yan Hu
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Jian Pan
- Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China
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16
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DE BRAEKELEER MARC, TOUS CORINE, GUÉGANIC NADIA, LE BRIS MARIEJOSÉE, BASINKO AUDREY, MOREL FRÉDÉRIC, DOUET-GUILBERT NATHALIE. Immunoglobulin gene translocations in chronic lymphocytic leukemia: A report of 35 patients and review of the literature. Mol Clin Oncol 2016; 4:682-694. [PMID: 27123263 PMCID: PMC4840758 DOI: 10.3892/mco.2016.793] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 02/09/2016] [Indexed: 12/20/2022] Open
Abstract
Chronic lymphocytic leukemia (CLL) represents the most common hematological malignancy in Western countries, with a highly heterogeneous clinical course and prognosis. Translocations involving the immunoglobulin (IG) genes are regularly identified. From 2000 to 2014, we identified an IG gene translocation in 18 of the 396 patients investigated at diagnosis (4.6%) and in 17 of the 275 analyzed during follow-up (6.2%). A total of 4 patients in whom the IG translocation was identified at follow-up did not carry the translocation at diagnosis. The IG heavy locus (IGH) was involved in 27 translocations (77.1%), the IG κ locus (IGK) in 1 (2.9%) and the IG λ locus (IGL) in 7 (20.0%). The chromosome band partners of the IG translocations were 18q21 in 16 cases (45.7%), 11q13 and 19q13 in 4 cases each (11.4% each), 8q24 in 3 cases (8.6%), 7q21 in 2 cases (5.7%), whereas 6 other bands were involved once (2.9% each). At present, 35 partner chromosomal bands have been described, but the partner gene has solely been identified in 10 translocations. CLL associated with IG gene translocations is characterized by atypical cell morphology, including plasmacytoid characteristics, and the propensity of being enriched in prolymphocytes. The IG heavy chain variable region (IGHV) mutational status varies between translocations, those with unmutated IGHV presumably involving cells at an earlier stage of B-cell lineage. All the partner genes thus far identified are involved in the control of cell proliferation and/or apoptosis. The translocated partner gene becomes transcriptionally deregulated as a consequence of its transposition into the IG locus. With the exception of t(14;18)(q32;q21) and its variants, prognosis appears to be poor for the other translocations. Therefore, searching for translocations involving not only IGH, but also IGL and IGK, by banding and molecular cytogenetics is required. Furthermore, it is important to identify the partner gene to ensure the patients receive the optimal treatment.
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Affiliation(s)
- MARC DE BRAEKELEER
- Faculty of Medicine and Health Sciences, University of Brest, Brest, France
- National Institute of Health and Medical Research (INSERM U1078), Brest, France
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Regional University Hospital Center of Brest (CHRU), Brest, France
| | - CORINE TOUS
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Regional University Hospital Center of Brest (CHRU), Brest, France
| | - NADIA GUÉGANIC
- Faculty of Medicine and Health Sciences, University of Brest, Brest, France
- National Institute of Health and Medical Research (INSERM U1078), Brest, France
| | - MARIE-JOSÉE LE BRIS
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Regional University Hospital Center of Brest (CHRU), Brest, France
| | - AUDREY BASINKO
- National Institute of Health and Medical Research (INSERM U1078), Brest, France
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Regional University Hospital Center of Brest (CHRU), Brest, France
| | - FRÉDÉRIC MOREL
- Faculty of Medicine and Health Sciences, University of Brest, Brest, France
- National Institute of Health and Medical Research (INSERM U1078), Brest, France
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Regional University Hospital Center of Brest (CHRU), Brest, France
| | - NATHALIE DOUET-GUILBERT
- Faculty of Medicine and Health Sciences, University of Brest, Brest, France
- National Institute of Health and Medical Research (INSERM U1078), Brest, France
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Regional University Hospital Center of Brest (CHRU), Brest, France
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17
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Palbociclib treatment of FLT3-ITD+ AML cells uncovers a kinase-dependent transcriptional regulation of FLT3 and PIM1 by CDK6. Blood 2016; 127:2890-902. [PMID: 27099147 DOI: 10.1182/blood-2015-11-683581] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 04/11/2016] [Indexed: 12/21/2022] Open
Abstract
Up to 30% of patients with acute myeloid leukemia have constitutively activating internal tandem duplications (ITDs) of the FLT3 receptor tyrosine kinase. Such mutations are associated with a poor prognosis and a high propensity to relapse after remission. FLT3 inhibitors are being developed as targeted therapy for FLT3-ITD(+) acute myeloid leukemia; however, their use is complicated by rapid development of resistance, which illustrates the need for additional therapeutic targets. We show that the US Food and Drug Administration-approved CDK4/6 kinase inhibitor palbociclib induces apoptosis of FLT3-ITD leukemic cells. The effect is specific for FLT3-mutant cells and is ascribed to the transcriptional activity of CDK6: CDK6 but not its functional homolog CDK4 is found at the promoters of the FLT3 and PIM1 genes, another important leukemogenic driver. There CDK6 regulates transcription in a kinase-dependent manner. Of potential clinical relevance, combined treatment with palbociclib and FLT3 inhibitors results in synergistic cytotoxicity. Simultaneously targeting two critical signaling nodes in leukemogenesis could represent a therapeutic breakthrough, leading to complete remission and overcoming resistance to FLT3 inhibitors.
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18
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Li Y, Liu D, López-Paz C, Olson BJ, Umen JG. A new class of cyclin dependent kinase in Chlamydomonas is required for coupling cell size to cell division. eLife 2016; 5:e10767. [PMID: 27015111 PMCID: PMC4841777 DOI: 10.7554/elife.10767] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 03/24/2016] [Indexed: 01/04/2023] Open
Abstract
Proliferating cells actively control their size by mechanisms that are poorly understood. The unicellular green alga Chlamydomonas reinhardtii divides by multiple fission, wherein a ‘counting’ mechanism couples mother cell-size to cell division number allowing production of uniform-sized daughters. We identified a sizer protein, CDKG1, that acts through the retinoblastoma (RB) tumor suppressor pathway as a D-cyclin-dependent RB kinase to regulate mitotic counting. Loss of CDKG1 leads to fewer mitotic divisions and large daughters, while mis-expression of CDKG1 causes supernumerous mitotic divisions and small daughters. The concentration of nuclear-localized CDKG1 in pre-mitotic cells is set by mother cell size, and its progressive dilution and degradation with each round of cell division may provide a link between mother cell-size and mitotic division number. Cell-size-dependent accumulation of limiting cell cycle regulators such as CDKG1 is a potentially general mechanism for size control. DOI:http://dx.doi.org/10.7554/eLife.10767.001 Most cells are programmed to maintain a certain size. This property, known as size control, is achieved by balancing growth and division, such that a cell will only divide after it reaches a certain size. However, and despite years of research, it is largely unknown how cells sense their size (or growth) to be able to divide accordingly. One theory proposes that there is a “sizer” protein inside cells, and that cells measure the abundance of this protein and use it to link cell size to the process of division. However, the existence of such a protein remained unproven. Li, Liu et al. have now used the cells of the green alga Chlamydomonas to identify a candidate sizer protein. Chlamydomonas cells, like many other algae, can grow to become very large mother cells that then divide one or more times in succession to produce many daughter cells. Larger mother cells undergo more divisions than smaller mother cells in order to produce daughter cells of a correct size. Using a range of genetic and biochemical techniques, Li, Liu et al. identified a protein that is produced in Chlamydomonas cells just before they begin to divide. Larger mother cells contain more of this protein than smaller cells and the protein encourages cells to divide. For example, mutant cells that lack this protein divided too few times, while cells that produce too much of it divided too many times. The protein, called CDKG1, belongs to a family of proteins that regulate cell division in many organisms. CDKG1 is a kinase – an enzyme that alters the activity of other proteins by adding a phosphate group on to them. In Chlamydomonas, CDKG1 couples cell size to cell division by altering the activity of an important protein called the retinoblastoma-related protein that controls cell division in numerous organisms. This protein is also frequently disrupted in cancers in humans. These findings shed new light on a molecular pathway for size control. Future work will need to determine how the accumulation of CDKG1 links to the size of a mother cell and how it is inactivated once daughter cells reach the appropriate size. DOI:http://dx.doi.org/10.7554/eLife.10767.002
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Affiliation(s)
- Yubing Li
- Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Plant Molecular and Cell Biology Program, the Horticultural and Plant Science Department, University of Florida, Gainesville, United States
| | - Dianyi Liu
- Donald Danforth Plant Science Center, St. Louis, United States
| | - Cristina López-Paz
- Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Donald Danforth Plant Science Center, St. Louis, United States
| | - Bradley Jsc Olson
- Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, United States
| | - James G Umen
- Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Donald Danforth Plant Science Center, St. Louis, United States
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19
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CDK6-a review of the past and a glimpse into the future: from cell-cycle control to transcriptional regulation. Oncogene 2015; 35:3083-91. [PMID: 26500059 DOI: 10.1038/onc.2015.407] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/22/2015] [Accepted: 09/22/2015] [Indexed: 12/19/2022]
Abstract
The G1 cell-cycle kinase CDK6 has long been thought of as a redundant homolog of CDK4. Although the two kinases have very similar roles in cell-cycle progression, it has recently become apparent that they differ in tissue-specific functions and contribute differently to tumor development. CDK6 is directly involved in transcription in tumor cells and in hematopoietic stem cells. These functions point to a role of CDK6 in tissue homeostasis and differentiation that is partially independent of CDK6's kinase activity and is not shared with CDK4. We review the literature on the contribution of CDK6 to transcription in an attempt to link the new findings on CDK6's transcriptional activity to cell-cycle progression. Finally, we note that anticancer therapies based on the inhibition of CDK6 kinase activity fail to take into account its kinase-independent role in tumor development.
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20
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Cdk4 and Cdk6 cooperate in counteracting the INK4 family of inhibitors during murine leukemogenesis. Blood 2014; 124:2380-90. [PMID: 25157181 DOI: 10.1182/blood-2014-02-555292] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Cdk4 and Cdk6 are related protein kinases that bind d-type cyclins and regulate cell-cycle progression. Cdk4/6 inhibitors are currently being used in advanced clinical trials and show great promise against many types of tumors. Cdk4 and Cdk6 are inhibited by INK4 proteins, which exert tumor-suppressing functions. To test the significance of this inhibitory mechanism, we generated knock-in mice that express a Cdk6 mutant (Cdk6 R31C) insensitive to INK4-mediated inhibition. Cdk6(R/R) mice display altered development of the hematopoietic system without enhanced tumor susceptibility, either in the presence or absence of p53. Unexpectedly, Cdk6 R31C impairs the potential of hematopoietic progenitors to repopulate upon adoptive transfer or after 5-fluorouracil-induced damage. The defects are overcome by eliminating sensitivity of cells to INK4 inhibitors by introducing the INK4-insensitive Cdk4 R24C allele, and INK4-resistant mice are more susceptible to hematopoietic and endocrine tumors. In BCR-ABL-transformed hematopoietic cells, Cdk6 R31C causes increased binding of p16(INK4a) to wild-type Cdk4, whereas cells harboring Cdk4 R24C and Cdk6 R31C are fully insensitive to INK4 inhibitors, resulting in accelerated disease onset. Our observations reveal that Cdk4 and Cdk6 cooperate in hematopoietic tumor development and suggest a role for Cdk6 in sequestering INK4 proteins away from Cdk4.
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21
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Xochelli A, Baliakas P, Moore S, Sole F, Wickham N, Salido M, Athanasiadou A, Oscier D, Stamatopoulos K. Translocation t(2;7)(p11.2;q21.2): a rare genetic aberration associated with B-cell lymphoproliferative disorders of marginal-zone origin. Cancer Genet 2014; 207:281-3. [DOI: 10.1016/j.cancergen.2014.06.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/10/2014] [Accepted: 06/19/2014] [Indexed: 12/22/2022]
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22
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Douet-Guilbert N, Tous C, Le Flahec G, Bovo C, Le Bris MJ, Basinko A, Morel F, De Braekeleer M. Translocation t(2;7)(p11;q21) associated with the CDK6/IGK rearrangement is a rare but recurrent abnormality in B-cell lymphoproliferative malignancies. Cancer Genet 2014; 207:83-6. [PMID: 24726269 DOI: 10.1016/j.cancergen.2014.02.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 02/21/2014] [Accepted: 02/24/2014] [Indexed: 01/22/2023]
Abstract
Structural abnormalities of chromosome 7q have been regularly reported in chronic B-cell lymphoproliferative disorders. They include chromosomal translocations involving 7q21, leading to overexpression of the CDK6 gene. Three different translocations, t(7;14)(q21;q32), t(7;22)(q21;q11), and t(2;7)(p11;q21), leading to the juxtaposition of the CDK6 gene with a immunoglobulin gene enhancer during B-cell differentiation, have been described. In the past 2 years, we identified three patients with lymphoproliferative malignancy associated with a t(2;7)(p11;q21). Fluorescent in situ hybridization using an IGK probe and a library of bacterial artificial chromosome (BAC) clones located in bands 7q21.2 and 7q21.3, containing CDK6, revealed that the telomeric part of the IGK probe was translocated on the der(7) within a 51-kb region upstream of the transcriptional start site of CDK6. A total of 23 patients with indolent B-cell lymphoproliferative disorders and juxtaposition of the IG and CDK6 genes, including 20 with IGK and CDK6 juxtaposition, have been reported thus far. This rearrangement leads to the overexpression of CDK6, which encodes a cyclin-dependent protein kinase involved in cell cycle G1 phase progression and G1/S transition.
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Affiliation(s)
- Nathalie Douet-Guilbert
- Laboratory of Histology, Embryology and Cytogenetics, Faculty of Medicine and Health Sciences, Université de Bretagne Occidentale, Brest, France; National Institute of Health and Medical Research (INSERM), Brest, France; Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France
| | - Corinne Tous
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France
| | - Glen Le Flahec
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France
| | - Clément Bovo
- Laboratory of Histology, Embryology and Cytogenetics, Faculty of Medicine and Health Sciences, Université de Bretagne Occidentale, Brest, France; National Institute of Health and Medical Research (INSERM), Brest, France
| | - Marie-Josée Le Bris
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France
| | - Audrey Basinko
- Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France
| | - Frédéric Morel
- Laboratory of Histology, Embryology and Cytogenetics, Faculty of Medicine and Health Sciences, Université de Bretagne Occidentale, Brest, France; National Institute of Health and Medical Research (INSERM), Brest, France; Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France
| | - Marc De Braekeleer
- Laboratory of Histology, Embryology and Cytogenetics, Faculty of Medicine and Health Sciences, Université de Bretagne Occidentale, Brest, France; National Institute of Health and Medical Research (INSERM), Brest, France; Department of Cytogenetics and Reproductive Biology, Morvan Hospital, Brest University and Regional Hospital, Brest, France.
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23
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Kollmann K, Heller G, Schneckenleithner C, Warsch W, Scheicher R, Ott R, Schäfer M, Fajmann S, Schlederer M, Schiefer AI, Reichart U, Mayerhofer M, Hoeller C, Zöchbauer-Müller S, Kerjaschki D, Bock C, Kenner L, Hoefler G, Freissmuth M, Green A, Moriggl R, Busslinger M, Malumbres M, Sexl V. A kinase-independent function of CDK6 links the cell cycle to tumor angiogenesis. Cancer Cell 2013; 24:167-81. [PMID: 23948297 PMCID: PMC3743049 DOI: 10.1016/j.ccr.2013.07.012] [Citation(s) in RCA: 203] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 05/17/2013] [Accepted: 07/22/2013] [Indexed: 12/20/2022]
Abstract
In contrast to its close homolog CDK4, the cell cycle kinase CDK6 is expressed at high levels in lymphoid malignancies. In a model for p185BCR-ABL+ B-acute lymphoid leukemia, we show that CDK6 is part of a transcription complex that induces the expression of the tumor suppressor p16INK4a and the pro-angiogenic factor VEGF-A. This function is independent of CDK6's kinase activity. High CDK6 expression thus suppresses proliferation by upregulating p16INK4a, providing an internal safeguard. However, in the absence of p16INK4a, CDK6 can exert its full tumor-promoting function by enhancing proliferation and stimulating angiogenesis. The finding that CDK6 connects cell-cycle progression to angiogenesis confirms CDK6's central role in hematopoietic malignancies and could underlie the selection pressure to upregulate CDK6 and silence p16INK4a.
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Affiliation(s)
- Karoline Kollmann
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Gerwin Heller
- Clinical Division of Oncology, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | | | - Wolfgang Warsch
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Ruth Scheicher
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Rene G. Ott
- Institute of Pharmacology, Center of Biomolecular Medicine and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Markus Schäfer
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Sabine Fajmann
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Michaela Schlederer
- Department of Clinical Pathology, Medical University of Vienna, 1090 Vienna, Austria
| | - Ana-Iris Schiefer
- Department of Clinical Pathology, Medical University of Vienna, 1090 Vienna, Austria
| | - Ursula Reichart
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Matthias Mayerhofer
- Department of Laboratory Medicine, Medical University of Vienna, 1090 Vienna, Austria
| | - Christoph Hoeller
- Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria
| | - Sabine Zöchbauer-Müller
- Clinical Division of Oncology, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Dontscho Kerjaschki
- Department of Clinical Pathology, Medical University of Vienna, 1090 Vienna, Austria
| | - Christoph Bock
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Lukas Kenner
- Ludwig Boltzmann Institute for Cancer Research, 1090 Vienna, Austria
| | - Gerald Hoefler
- Department of Pathology, Medical University of Graz, 8036 Graz, Austria
| | - Michael Freissmuth
- Institute of Pharmacology, Center of Biomolecular Medicine and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Anthony R. Green
- Cambridge Institute for Medical Research and Wellcome Trust/MRC Stem Cell Institute, University of Cambridge, Cambridge CB2 0XY, UK
- Department of Hematology, University of Cambridge, Cambridge CB2 0XY, UK
- Department of Hematology, Addenbrooke’s Hospital, Cambridge CB2 0XY, UK
| | - Richard Moriggl
- Ludwig Boltzmann Institute for Cancer Research, 1090 Vienna, Austria
| | - Meinrad Busslinger
- Institute of Pharmacology, Center of Biomolecular Medicine and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Marcos Malumbres
- Cell Division and Cancer Group, Molecular Oncology Programme, Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain
| | - Veronika Sexl
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
- Corresponding author
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24
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Giacomini CP, Sun S, Varma S, Shain AH, Giacomini MM, Balagtas J, Sweeney RT, Lai E, Del Vecchio CA, Forster AD, Clarke N, Montgomery KD, Zhu S, Wong AJ, van de Rijn M, West RB, Pollack JR. Breakpoint analysis of transcriptional and genomic profiles uncovers novel gene fusions spanning multiple human cancer types. PLoS Genet 2013; 9:e1003464. [PMID: 23637631 PMCID: PMC3636093 DOI: 10.1371/journal.pgen.1003464] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/05/2013] [Indexed: 02/07/2023] Open
Abstract
Gene fusions, like BCR/ABL1 in chronic myelogenous leukemia, have long been recognized in hematologic and mesenchymal malignancies. The recent finding of gene fusions in prostate and lung cancers has motivated the search for pathogenic gene fusions in other malignancies. Here, we developed a “breakpoint analysis” pipeline to discover candidate gene fusions by tell-tale transcript level or genomic DNA copy number transitions occurring within genes. Mining data from 974 diverse cancer samples, we identified 198 candidate fusions involving annotated cancer genes. From these, we validated and further characterized novel gene fusions involving ROS1 tyrosine kinase in angiosarcoma (CEP85L/ROS1), SLC1A2 glutamate transporter in colon cancer (APIP/SLC1A2), RAF1 kinase in pancreatic cancer (ATG7/RAF1) and anaplastic astrocytoma (BCL6/RAF1), EWSR1 in melanoma (EWSR1/CREM), CDK6 kinase in T-cell acute lymphoblastic leukemia (FAM133B/CDK6), and CLTC in breast cancer (CLTC/VMP1). Notably, while these fusions involved known cancer genes, all occurred with novel fusion partners and in previously unreported cancer types. Moreover, several constituted druggable targets (including kinases), with therapeutic implications for their respective malignancies. Lastly, breakpoint analysis identified new cell line models for known rearrangements, including EGFRvIII and FIP1L1/PDGFRA. Taken together, we provide a robust approach for gene fusion discovery, and our results highlight a more widespread role of fusion genes in cancer pathogenesis. Gene fusions represent an important class of cancer genes, created by rearrangements of the genome that bring together two different genes. Because they are unique to cancer cells, gene fusions are ideal diagnostic markers and therapeutic targets. While gene fusions were once thought restricted mainly to blood cancers, recent discoveries suggest they are more widespread. Here, we have developed an approach for mining DNA microarray data to detect the tell-tale signatures of gene fusions, as “breakpoints” occurring within the encoding DNA or expressed transcripts. We apply this approach to a large collection of nearly 1,000 human cancer specimens. From this analysis, we discover and verify twelve new gene fusions occurring in diverse cancer types. We verify that some of these rearrangements recur in other samples of the same cancer type (supporting a causal role) and that the cancers show dependency on the fusion for cancer cell growth. Notably, some of these fusions (e.g. CEP85L/ROS1 in angiosarcoma) represent the first for that cancer type and thus provide important new biological insight. Some are also good drug targets (including rearrangements of ROS1, RAF1, and CDK6 kinases), with clear implications for therapy.
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Affiliation(s)
- Craig P. Giacomini
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Steven Sun
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Sushama Varma
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - A. Hunter Shain
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Marilyn M. Giacomini
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Jay Balagtas
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
- Department of Pediatrics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Robert T. Sweeney
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Everett Lai
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Catherine A. Del Vecchio
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, United States of America
| | - Andrew D. Forster
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Nicole Clarke
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Kelli D. Montgomery
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Shirley Zhu
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Albert J. Wong
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, United States of America
| | - Matt van de Rijn
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Robert B. West
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Jonathan R. Pollack
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail:
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25
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Parker EPK, Siebert R, Oo TH, Schneider D, Hayette S, Wang C. Sequencing of t(2;7) translocations reveals a consistent breakpoint linking CDK6 to the IGK locus in indolent B-cell neoplasia. J Mol Diagn 2012; 15:101-9. [PMID: 23127611 DOI: 10.1016/j.jmoldx.2012.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Revised: 07/09/2012] [Accepted: 07/13/2012] [Indexed: 01/30/2023] Open
Abstract
The translocation t(2;7)(p11;q21) has repeatedly been documented in association with indolent B-cell lymphoproliferative disorders (BLPDs). However, the chromosomal breakpoints associated with this recurrent translocation have rarely been characterized. Using an approach based on long-range PCR, we mapped the t(2;7) breakpoints in five patients presenting with indolent B-cell neoplasia. The sequencing of these rearrangements revealed several striking parallels across the t(2;7) breakpoints. The junction sites on 2p11 consistently mapped to the heptamer recombination signal sequence (RSS) of an immunoglobulin kappa variable gene (IGK) within the Vκ3 family, while the breakpoints on 7q21 each localized to within 4 bp of an RSS-like element located approximately 0.5 kb upstream of the transcription start site of the cyclin-dependent kinase 6 gene (CDK6). These findings confirm the significant genetic overlap arising in BLPD-associated t(2;7) translocations, and implicate the deregulated expression of CDK6 as a common molecular mechanism involved in the emergence of clonal B-cell proliferations presenting with this recurrent abnormality. In addition, the successful mapping of the t(2;7) translocations in each of five patients using a simple PCR-based protocol highlights the potential diagnostic utility of this approach during characterization of cases harboring analogous rearrangements.
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Affiliation(s)
- Edward P K Parker
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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26
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Abstract
The cell cycle is regulated in part by cyclins and their associated serine/threonine cyclin-dependent kinases, or CDKs. CDK4, in conjunction with the D-type cyclins, mediates progression through the G1 phase when the cell prepares to initiate DNA synthesis. Although CDK4-null mutant mice are viable and cell proliferation is not significantly affected in vitro due to compensatory roles played by other CDKs, this gene plays a key role in mammalian development and cancer. This review discusses the role that CDK4 plays in cell cycle control, normal development, and tumorigenesis as well as how small molecule inhibitors of CDK4 can be used to treat disease.
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27
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Haferlach C, Bacher U, Grossmann V, Schindela S, Zenger M, Kohlmann A, Kern W, Haferlach T, Schnittger S. Three novel cytogenetically cryptic EVI1 rearrangements associated with increased EVI1 expression and poor prognosis identified in 27 acute myeloid leukemia cases. Genes Chromosomes Cancer 2012; 51:1079-85. [PMID: 22887804 DOI: 10.1002/gcc.21992] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 07/09/2012] [Indexed: 11/06/2022] Open
Abstract
In acute myeloid leukemia (AML), increased ecotropic virus integration site 1 protein homolog (EVI1) gene expression is prognostically unfavorable. Subsets of cases show 3q26 rearrangements, such as inv(3)(q21q26)/t(3;3)(q21;q26), frequently accompanied by chromosome 7 abnormalities. We investigated whether cytogenetically cryptic EVI1 rearrangements may cause EVI1 overexpression in myeloid malignancies without 3q26 abnormalities and investigated 983 patients with AML (n = 606) or myelodysplastic syndromes (MDS; n = 377) with normal karyotype (CN-AML/CN-MDS, n = 594) or chromosome 7 abnormalities (n = 389) for EVI1 rearrangements using interphase FISH. We identified cytogenetically cryptic EVI1 rearrangements in 27 patients (19 AML, 8 MDS): inv(3)(p24q26) [n = 10]; t(3;21)(q26;q11) [n = 9]; and der(7)t(3;7)(q26;q21) [n = 8]. Elevated EVI1 expression was detected in nearly all cases with cryptic EVI1 rearrangements: Median %EVI1/ABL1 was 92.8 (range: 29.8-146.1) in inv(3)(p24q26), 104.9 (41.4-176.3) in t(3;21)(q26;q11), and 101.8 (4.4-210.4) in der(7)t(3;7)(q26;q21). This was similar to median %EVI1/ABL1 of 73.9 (range: 7.3-585.6) in an independent cohort of inv(3)(q21q26)/t(3;3)(q21;q26) and 67.1 (2.3-410.7) in other 3q26/EVI1 rearrangements. Healthy controls showed median EVI1 expression of 0.5 (range: 0.0-5.8). Using SNP microarray and sequencing analyses, the breakpoints of der(7)t(3;7)(q26;q21) were assigned to CDK6 and centromeric of EVI1, and of t(3;21)(q26;q11) to be within EVI1 and NRIP1. Median overall survival in patients with cryptic EVI1 rearrangements was short, comparable to patients with inv(3)(q21q26)/t(3;3)(q21;q26) or other EVI1 rearrangements. Cryptic EVI1 rearrangements contribute to explain the clinical heterogeneity of CN-AML and are associated with elevated EVI1 expression and an unfavorable prognosis. Screening for cryptic EVI1 rearrangements by FISH may be particularly appropriate in CN-AML with elevated EVI1 expression or in AML/MDS patients with chromosome 7 abnormalities.
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28
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Parker E, Macdonald JR, Wang C. Molecular characterization of a t(2;7) translocation linking CDK6 to the IGK locus in CD5(-) monoclonal B-cell lymphocytosis. Cancer Genet 2011; 204:260-4. [PMID: 21665179 DOI: 10.1016/j.cancergen.2011.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 03/01/2011] [Accepted: 03/15/2011] [Indexed: 12/19/2022]
Abstract
The term monoclonal B-cell lymphocytosis (MBL) is used to characterize individuals with a circulating population of clonal B-cells and no other features of a lymphoproliferative disorder. Although several recent studies have examined the molecular basis of this condition, the subgroup of MBL lacking CD5 expression has been largely overlooked. In this study, we sequenced a t(2;7) in a patient with persistent but non-progressing CD5(-) MBL. This revealed a breakpoint at 2p11.2 localized to the recombination signal sequence (RSS) of the immunoglobulin κ (IGK) variable gene IGKV3-15, and a breakpoint at 7q21.2 located 520 base pairs (bp) upstream of the transcription start site of cyclin-dependent kinase 6 (CDK6 ). The 7q breakpoint showed perfect sequence homology to the immunoglobulin RSS heptamer, and was located within 3 bp of a t(2;7) junction previously characterized in splenic marginal zone lymphoma (SMZL). These findings highlight a genetic link between CD5(-) MBL and SMZL, and implicate the dysregulation of CDK6 in the emergence of this preclinical disorder.
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Affiliation(s)
- Edward Parker
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, ON, Canada
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29
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Lomonosov M, Meziane EK, Ye H, Nelson DE, Randle SJ, Laman H. Expression of Fbxo7 in haematopoietic progenitor cells cooperates with p53 loss to promote lymphomagenesis. PLoS One 2011; 6:e21165. [PMID: 21695055 PMCID: PMC3117880 DOI: 10.1371/journal.pone.0021165] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 05/21/2011] [Indexed: 12/22/2022] Open
Abstract
Fbxo7 is an unusual F box protein that augments D-type cyclin complex formation with Cdk6, but not Cdk4 or Cdk2, and its over-expression has been demonstrated to transform immortalised fibroblasts in a Cdk6-dependent manner. Here we present new evidence in vitro and in vivo on the oncogenic potential of this regulatory protein in primary haematopoietic stem and progenitor cells (HSPCs). Increasing Fbxo7 expression in HSPCs suppressed their colony forming ability in vitro, specifically decreasing CD11b (Mac1) expression, and these effects were dependent on an intact p53 pathway. Furthermore, increased Fbxo7 levels enhanced the proliferative capacity of p53 null HSPCs when they were grown in reduced concentrations of stem cell factor. Finally, irradiated mice reconstituted with p53 null, but not wild-type, HSPCs expressing Fbxo7 showed a statistically significant increase in the incidence of T cell lymphoma in vivo. These data argue that Fbxo7 negatively regulates the proliferation and differentiation of HSPCs in a p53-dependent manner, and that in the absence of p53, Fbxo7 expression can promote T cell lymphomagenesis.
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Affiliation(s)
- Mikhail Lomonosov
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - El Kahina Meziane
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Hongtao Ye
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - David E. Nelson
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Suzanne J. Randle
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Heike Laman
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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30
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c-JUN promotes BCR-ABL-induced lymphoid leukemia by inhibiting methylation of the 5' region of Cdk6. Blood 2011; 117:4065-75. [PMID: 21300982 DOI: 10.1182/blood-2010-07-299644] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The transcription factor c-JUN and its upstream kinase JNK1 have been implicated in BCR-ABL-induced leukemogenesis. JNK1 has been shown to regulate BCL2 expression, thereby altering leukemogenesis, but the impact of c-JUN remained unclear. In this study, we show that JNK1 and c-JUN promote leukemogenesis via separate pathways, because lack of c-JUN impairs proliferation of p185(BCR-ABL)-transformed cells without affecting their viability. The decreased proliferation of c-Jun(Δ/Δ) cells is associated with the loss of cyclin-dependent kinase 6 (CDK6) expression. In c-Jun(Δ/Δ) cells, CDK6 expression becomes down-regulated upon BCR-ABL-induced transformation, which correlates with CpG island methylation within the 5' region of Cdk6. We verified the impact of Cdk6 deficiency using Cdk6(-/-) mice that developed BCR-ABL-induced B-lymphoid leukemia with significantly increased latency and an attenuated disease phenotype. In addition, we show that reexpression of CDK6 in BCR-ABL-transformed c-Jun(Δ/Δ) cells reconstitutes proliferation and tumor formation in Nu/Nu mice. In summary, our study reveals a novel function for the activating protein 1 (AP-1) transcription factor c-JUN in leukemogenesis by antagonizing promoter methylation. Moreover, we identify CDK6 as relevant and critical target of AP-1-regulated DNA methylation on BCR-ABL-induced transformation, thereby accelerating leukemogenesis.
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31
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Clinicopathologic features of CDK6 translocation-associated B-cell lymphoproliferative disorders. Am J Surg Pathol 2009; 33:720-9. [PMID: 19145199 DOI: 10.1097/pas.0b013e3181934244] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cyclin-dependent protein kinase 6 (CDK6), in cooperation with cyclin Ds, drives cell cycle progression from G1 to S phase through phosphorylation and subsequent inactivation of retinoblastoma 1 protein. Alteration of this pathway results in both nonhematologic and hematologic malignancies, which include a small subset of B-cell lymphoproliferative disorders (BLPDs). We identified 5 cases of BLPD that carried CDK6 chromosomal translocations and characterized their clinical, pathologic, immunophenotypic, and genetic features. Common clinical characteristics included marked neoplastic lymphocytosis, systemic lymphadenopathy, splenomegaly, and bone marrow involvement. Three patients were diagnosed with low-grade B-cell lymphoma and had an indolent clinical course, and 2 patients (one who transformed to large B-cell lymphoma, and the other who was initially diagnosed with a high-grade B-cell lymphoma) had an aggressive clinical course. Immunophenotypically, the neoplastic B cells expressed CD5, CDK6, and cytoplasmic retinoblastoma 1 protein in all cases, expressed phospho-RB, p27kip1, and cyclin D2 in most cases, and uniformly lacked expression of all other cyclins. In 4 cases, the CDK6 translocation partner was kappa immunoglobulin light-chain gene; and in the fifth case, the CDK6 translocation partner was unknown. These distinct clinicopathologic and cytogenetic features distinguish the CDK6 translocation-associated BLPDs (CDK6-BLPDs) from other mature B-cell lymphomas.
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32
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Zhang H, Chen Y. New insight into the role of miRNAs in leukemia. ACTA ACUST UNITED AC 2009; 52:224-31. [PMID: 19294347 DOI: 10.1007/s11427-009-0036-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Accepted: 11/28/2008] [Indexed: 12/11/2022]
Abstract
Recent studies have shown that microRNAs(miRNAs) play an important role in cell differentiation, growth, and death, including the functional study of miRNAs in tumorigenesis. To date, miRNA expression profiles in many types of cancers have been identified and miRNA expression signatures associated with types and cytogenetics of leukemia have also been reported. Increasing evidence has shown that miRNAs could function as either tumor suppressors or oncogenes in cancers such as leukemia, while other miRNAs might be benefitcial for diagnosis and prognosis, predicted to be newly developed biomarkers. In this review, we summarize the recent progress about miRNAs in leukemia and present a miRNA-mediated network involved in differentiation, proliferation and apoptosis predicted to be the roles of miRNAs in the pathogenesis of leukemia.
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Affiliation(s)
- Hua Zhang
- Key Laboratory of Genetic Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, Sun Yan-Sen University, Guangzhou, 510275, China
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33
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Zheng D, Cho YY, Lau ATY, Zhang J, Ma WY, Bode AM, Dong Z. Cyclin-dependent kinase 3-mediated activating transcription factor 1 phosphorylation enhances cell transformation. Cancer Res 2008; 68:7650-60. [PMID: 18794154 DOI: 10.1158/0008-5472.can-08-1137] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cyclin-dependent kinase (cdk)-3, a member of the cdk family of kinases, plays a critical role in cell cycle regulation and is involved in G(0)-G(1) and G(1)-S cell cycle transitions. However, the role of cdk3 in cell proliferation, as well as cell transformation, is not yet clearly understood. Here, we report that the protein expression level of cdk3 is higher in human cancer cell lines and human glioblastoma tissue compared with normal brain tissue. Furthermore, we found that cdk3 phosphorylates activating transcription factor 1 (ATF1) at serine 63 and enhances the transactivation and transcriptional activities of ATF1. Results also indicated that siRNA directed against cdk3 (si-cdk3) suppresses ATF1 activity, resulting in inhibition of proliferation and growth of human glioblastoma T98G cells in soft agar. Importantly, we showed that cdk3 enhances epidermal growth factor-induced transformation of JB6 Cl41 cells and si-cdk3 suppresses Ras(G12V)/cdk3/ATF1-induced foci formation in NIH3T3 cells. These results clearly showed that the cdk3-ATF1 signaling axis is critical for cell proliferation and transformation.
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Affiliation(s)
- Duo Zheng
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
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Cavazzini F, Hernandez JA, Gozzetti A, Russo Rossi A, De Angeli C, Tiseo R, Bardi A, Tammiso E, Crupi R, Lenoci MP, Forconi F, Lauria F, Marasca R, Maffei R, Torelli G, Gonzalez M, Martin-Jimenez P, Maria Hernandez J, Rigolin GM, Cuneo A. Chromosome 14q32 translocations involving the immunoglobulin heavy chain locus in chronic lymphocytic leukaemia identify a disease subset with poor prognosis. Br J Haematol 2008; 142:529-37. [DOI: 10.1111/j.1365-2141.2008.07227.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Nagel S, Leich E, Quentmeier H, Meyer C, Kaufmann M, Drexler HG, Zettl A, Rosenwald A, MacLeod RAF. Amplification at 7q22 targets cyclin-dependent kinase 6 in T-cell lymphoma. Leukemia 2007; 22:387-92. [PMID: 17989712 DOI: 10.1038/sj.leu.2405028] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recurrent chromosomal aberrations in hematopoietic tumors target genes involved in pathogenesis. Their identification and functional characterization are therefore important for the establishment of rational therapies. Here, we investigated genomic amplification at 7q22 in the T-cell lymphoma cell line SU-DHL-1 belonging to the subtype of anaplastic large-cell lymphoma (ALCL). Cytogenetic analysis mapped this amplicon to 86-95 Mb. Copy-number determination quantified the amplification level at 5- to 6-fold. Expression analysis of genes located within this region identified cyclin-dependent kinase 6 (CDK6) as a potential amplification target. In comparison with control cell lines, SU-DHL-1 expressed considerably higher levels of CDK6. Functionally, SU-DHL-1 cells exhibited reduced sensitivity to rapamycin treatment, as indicated by cell growth and cell cycle analysis. Rapamycin reportedly inhibits degradation of the CDK inhibitor p27 with concomitant downregulation of cyclin D3, implying a proliferative advantage for CDK6 overexpression. Amplification of the CDK6 locus was analyzed in primary T-cell lymphoma samples and, while detected infrequently in those classified as ALCL (1%), was detected in 23% of peripheral T-cell lymphomas not otherwise specified. Taken together, analysis of the 7q22 amplicon identified CDK6 as an important cell cycle regulator in T-cell lymphomas, representing a novel potential target for rational therapy.
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Affiliation(s)
- S Nagel
- Department of Human and Animal Cell Cultures, DSMZ, Braunschweig, Germany.
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Malumbres M, Barbacid M. Mammalian cyclin-dependent kinases. Trends Biochem Sci 2005; 30:630-41. [PMID: 16236519 DOI: 10.1016/j.tibs.2005.09.005] [Citation(s) in RCA: 869] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2005] [Revised: 08/11/2005] [Accepted: 09/15/2005] [Indexed: 02/02/2023]
Abstract
Cyclin-dependent kinases (Cdks) are the catalytic subunits of a family of mammalian heterodimeric serine/threonine kinases that have been implicated in the control of cell-cycle progression, transcription and neuronal function. Recent genetic evidence obtained with gene-targeted mice has shown that Cdk4 and Cdk6 are not needed for entry into the cell cycle after mitogenic stimuli and organogenesis; however, they are essential for the proliferation of some endocrine and hematopoietic cells. Cdk2 is also dispensable for the mitotic cell cycle. Indeed, mice without Cdk2 are normal except for their complete sterility: unexpectedly, Cdk2 is crucial for the first meiotic division of male and female germ cells. These findings have important implications both for our current understanding of the role of Cdks in regulating the mammalian cell cycle and for their potential use as therapeutic targets in cancer.
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Affiliation(s)
- Marcos Malumbres
- Molecular Oncology Programme, Centro Nacional de Investigaciones Oncológicas, Melchor Fernández Almagro 3, E-28029 Madrid, Spain.
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Laman H, Funes JM, Ye H, Henderson S, Galinanes-Garcia L, Hara E, Knowles P, McDonald N, Boshoff C. Transforming activity of Fbxo7 is mediated specifically through regulation of cyclin D/cdk6. EMBO J 2005; 24:3104-16. [PMID: 16096642 PMCID: PMC1201355 DOI: 10.1038/sj.emboj.7600775] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2005] [Accepted: 07/18/2005] [Indexed: 12/19/2022] Open
Abstract
D cyclins (D1, D2 and D3) and their catalytic subunits (cyclin-dependent kinases cdk4 and cdk6) have a facilitating, but nonessential, role in cell cycle entry. Tissue-specific functions for D-type cyclins and cdks have been reported; however, the biochemical properties of these kinases are indistinguishable. We report that an F box protein, Fbxo7, interacted with cellular and viral D cyclins and distinguished among the cdks that bind D-type cyclins, specifically binding cdk6, in vitro and in vivo. Fbxo7 specifically regulated D cyclin/cdk6 complexes: Fbxo7 knockdown decreased cdk6 association with cyclin and its overexpression increased D cyclin/cdk6 activity and E2F activity. Fbxo7 interacted with p27, but its enhancement of cyclin D/cdk6 activity was p21/p27 independent. Fbxo7 overexpression transformed murine fibroblasts, rendering them tumorigenic in athymic nude mice. Transformed phenotypes were dependent on cdk6, as knockdown of cdk6 reversed them. Fbxo7 was highly expressed in epithelial tumors, but not in normal tissues, suggesting that it may have a proto-oncogenic role in human cancers.
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Affiliation(s)
- Heike Laman
- Cancer Research UK, Viral Oncology Group, Wolfson Institute for Biomedical Research, University College London, London, UK.
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Gerland LM, Genestier L, Peyrol S, Michallet MC, Hayette S, Urbanowicz I, Ffrench P, Magaud JP, Ffrench M. Autolysosomes accumulate during in vitro CD8+ T-lymphocyte aging and may participate in induced death sensitization of senescent cells. Exp Gerontol 2004; 39:789-800. [PMID: 15130673 DOI: 10.1016/j.exger.2004.01.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2003] [Revised: 01/07/2004] [Accepted: 01/29/2004] [Indexed: 12/31/2022]
Abstract
As autophagic inclusions accumulate in senescent fibroblasts, we wondered whether an increase in cellular fragility during in vitro lymphocyte aging may be related to an autolysosome accumulation. We established that, during long-term cultures, repeatedly stimulated T-lymphocytes acquired characteristics of replicative senescence and became progressively intolerant to activation. Cell death following stimulations: (i) corresponded to apoptosis, associated with necrosis at the end of the culture; (ii) was not, for its main part, mediated through CD95/CD178 or TNFRII/TNF alpha interactions; and (iii) occurred in spite of bcl-2 increased expression. After 14 weeks of culture, the percentage of lymphocytes containing at least one autophagic inclusion (p<0.0001) and the lipofuscin autofluorescence in lymphocytes (p<0.0001) were significantly increased. The expression of several genes regulating autophagy did not significantly vary with the age of the culture. Forty-eight hours after each stimulation, the percentage of induced cell death rose while, in the remaining living cells, the percentage of lymphocytes with autophagic vacuoles (p<0.05), with beta-galactosidase activity and the lipofuscin autofluorescence (p<0.001) significantly decreased, suggesting the preferential death of cells with autophagy. Our data support the view that the accumulation of autolysosomes in senescent lymphocytes might aggravate cellular fragility, leading to apoptosis and necrosis mainly induced by lymphocyte activation.
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Affiliation(s)
- Luc-Marie Gerland
- Laboratoire de Cytologie Analytique, Faculté de Médecine, INSERM U 590, 69373 Lyon Cedex 08, France
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Su XY, Busson M, Della Valle V, Ballerini P, Dastugue N, Talmant P, Ferrando AA, Baudry-Bluteau D, Romana S, Berger R, Bernard OA. Various types of rearrangements targetTLX3 locus in T-cell acute lymphoblastic leukemia. Genes Chromosomes Cancer 2004; 41:243-9. [PMID: 15334547 DOI: 10.1002/gcc.20088] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Most chromosomal translocations observed in T-cell acute lymphoblastic leukemia (T-ALL) often produce transcriptional activation of transcription factor oncogenes. Ectopic expression of the TLX3 (also known as HOX11L2) gene has been shown to be associated with a cryptic t(5;14)(q35;q32) translocation specific for a subtype of T-ALL. Here we report several examples of variant and alternative translocations resulting in expression of TLX3 in T-ALL, and we describe three of these translocations in detail. In particular, the CDK6 gene was rearranged in two t(5;7)(q35;q21) translocations. In two additional instances, fusion of the BCL11B (also known as CTIP2) and RANBP17/TLX3 loci were shown to result from subtle genomic insertion/deletion within these loci. This study further underscores that TLX3 expression in T-ALL is strongly associated with the presence of genomic rearrangements.
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Affiliation(s)
- Xin Ying Su
- INSERM E0210, IRNEM, Hôpital Necker, Paris, France
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