1
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Walker RL, Hornicek FJ, Duan Z. Transcriptional regulation and therapeutic potential of cyclin-dependent kinase 9 (CDK9) in sarcoma. Biochem Pharmacol 2024; 226:116342. [PMID: 38848777 DOI: 10.1016/j.bcp.2024.116342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/17/2024] [Accepted: 06/04/2024] [Indexed: 06/09/2024]
Abstract
Sarcomas include various subtypes comprising two significant groups - soft tissue and bone sarcomas. Although the survival rate for some sarcoma subtypes has improved over time, the current methods of treatment remain efficaciously limited, as recurrent, and metastatic diseases remain a major obstacle. There is a need for better options and therapeutic strategies in treating sarcoma. Cyclin dependent kinase 9 (CDK9) is a transcriptional kinase and has emerged as a promising target for treating various cancers. The aberrant expression and activation of CDK9 have been observed in several sarcoma subtypes, including rhabdomyosarcoma, synovial sarcoma, osteosarcoma, Ewing sarcoma, and chordoma. Enhanced CDK9 expression has also been correlated with poorer prognosis in sarcoma patients. As a master regulator of transcription, CDK9 promotes transcription elongation by phosphorylation and releasing RNA polymerase II (RNAPII) from its promoter proximal pause. Release of RNAPII from this pause induces transcription of critical genes in the tumor cell. Overexpression and activation of CDK9 have been observed to lead to the expression of oncogenes, including MYC and MCL-1, that aid sarcoma development and progression. Inhibition of CDK9 in sarcoma has been proven to reduce these oncogenes' expression and decrease proliferation and growth in different sarcoma cells. Currently, there are several CDK9 inhibitors in preclinical and clinical investigations. This review aims to highlight the recent discovery and results on the transcriptional role and therapeutic potential of CDK9 in sarcoma.
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Affiliation(s)
- Robert L Walker
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA
| | - Francis J Hornicek
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA
| | - Zhenfeng Duan
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA.
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2
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Candido MF, Medeiros M, Veronez LC, Bastos D, Oliveira KL, Pezuk JA, Valera ET, Brassesco MS. Drugging Hijacked Kinase Pathways in Pediatric Oncology: Opportunities and Current Scenario. Pharmaceutics 2023; 15:pharmaceutics15020664. [PMID: 36839989 PMCID: PMC9966033 DOI: 10.3390/pharmaceutics15020664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/18/2023] Open
Abstract
Childhood cancer is considered rare, corresponding to ~3% of all malignant neoplasms in the human population. The World Health Organization (WHO) reports a universal occurrence of more than 15 cases per 100,000 inhabitants around the globe, and despite improvements in diagnosis, treatment and supportive care, one child dies of cancer every 3 min. Consequently, more efficient, selective and affordable therapeutics are still needed in order to improve outcomes and avoid long-term sequelae. Alterations in kinases' functionality is a trademark of cancer and the concept of exploiting them as drug targets has burgeoned in academia and in the pharmaceutical industry of the 21st century. Consequently, an increasing plethora of inhibitors has emerged. In the present study, the expression patterns of a selected group of kinases (including tyrosine receptors, members of the PI3K/AKT/mTOR and MAPK pathways, coordinators of cell cycle progression, and chromosome segregation) and their correlation with clinical outcomes in pediatric solid tumors were accessed through the R2: Genomics Analysis and Visualization Platform and by a thorough search of published literature. To further illustrate the importance of kinase dysregulation in the pathophysiology of pediatric cancer, we analyzed the vulnerability of different cancer cell lines against their inhibition through the Cancer Dependency Map portal, and performed a search for kinase-targeted compounds with approval and clinical applicability through the CanSAR knowledgebase. Finally, we provide a detailed literature review of a considerable set of small molecules that mitigate kinase activity under experimental testing and clinical trials for the treatment of pediatric tumors, while discuss critical challenges that must be overcome before translation into clinical options, including the absence of compounds designed specifically for childhood tumors which often show differential mutational burdens, intrinsic and acquired resistance, lack of selectivity and adverse effects on a growing organism.
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Affiliation(s)
- Marina Ferreira Candido
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil
| | - Mariana Medeiros
- Regional Blood Center, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil
| | - Luciana Chain Veronez
- Department of Pediatrics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil
| | - David Bastos
- Department of Biology, Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | - Karla Laissa Oliveira
- Department of Biology, Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | - Julia Alejandra Pezuk
- Departament of Biotechnology and Innovation, Anhanguera University of São Paulo, UNIAN/SP, São Paulo 04119-001, SP, Brazil
| | - Elvis Terci Valera
- Department of Pediatrics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil
| | - María Sol Brassesco
- Departament of Biotechnology and Innovation, Anhanguera University of São Paulo, UNIAN/SP, São Paulo 04119-001, SP, Brazil
- Correspondence: ; Tel.: +55-16-3315-9144; Fax: +55-16-3315-4886
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3
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Thiel JT, Daigeler A, Kolbenschlag J, Rachunek K, Hoffmann S. The Role of CDK Pathway Dysregulation and Its Therapeutic Potential in Soft Tissue Sarcoma. Cancers (Basel) 2022; 14:3380. [PMID: 35884441 PMCID: PMC9323700 DOI: 10.3390/cancers14143380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/07/2022] [Accepted: 07/09/2022] [Indexed: 02/04/2023] Open
Abstract
Soft tissue sarcomas (STSs) are tumors that are challenging to treat due to their pathologic and molecular heterogeneity and their tumor biology that is not yet fully understood. Recent research indicates that dysregulation of cyclin-dependent kinase (CDK) signaling pathways can be a strong driver of sarcogenesis. CDKs are enzyme forms that play a crucial role in cell-cycle control and transcription. They belong to the protein kinases group and to the serine/threonine kinases subgroup. Recently identified CDK/cyclin complexes and established CDK/cyclin complexes that regulate the cell cycle are involved in the regulation of gene expression through phosphorylation of critical components of transcription and pre-mRNA processing mechanisms. The current and continually growing body of data shows that CDKs play a decisive role in tumor development and are involved in the proliferation and growth of sarcoma cells. Since the abnormal expression or activation of large numbers of CDKs is considered to be characteristic of cancer development and progression, dysregulation of the CDK signaling pathways occurs in many subtypes of STSs. This review discusses how reversal and regulation can be achieved with new therapeutics and summarizes the current evidence from studies regarding CDK modulation for STS treatment.
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Affiliation(s)
- Johannes Tobias Thiel
- Department of Hand, Plastic, Reconstructive and Burn Surgery, BG Unfallklinik Tuebingen, University of Tuebingen, 72076 Tuebingen, Germany; (A.D.); (J.K.); (K.R.); (S.H.)
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4
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Marak BN, Dowarah J, Khiangte L, Singh VP. A comprehensive insight on the recent development of Cyclic Dependent Kinase inhibitors as anticancer agents. Eur J Med Chem 2020; 203:112571. [DOI: 10.1016/j.ejmech.2020.112571] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/09/2020] [Accepted: 06/11/2020] [Indexed: 12/19/2022]
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5
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Cassandri M, Fioravanti R, Pomella S, Valente S, Rotili D, Del Baldo G, De Angelis B, Rota R, Mai A. CDK9 as a Valuable Target in Cancer: From Natural Compounds Inhibitors to Current Treatment in Pediatric Soft Tissue Sarcomas. Front Pharmacol 2020; 11:1230. [PMID: 32903585 PMCID: PMC7438590 DOI: 10.3389/fphar.2020.01230] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/28/2020] [Indexed: 12/20/2022] Open
Abstract
Cyclin-Dependent Kinases (CDKs) are well-known reliable targets for cancer treatment being often deregulated. Among them, since the transcription-associated CDK9 represents the sentry of cell transcriptional homeostasis, it can be a valuable target for managing cancers in which the transcriptional machinery is dysregulated by tumor-driver oncogenes. Here we give an overview of some natural compounds identified as CDK inhibitors with reported activity also against CDK9, that were taken as a model for the development of highly active synthetic anti-CDK9 agents. After, we summarize the data on CDK9 inhibition in a group of rare pediatric solid tumors such as rhabdomyosarcoma, Ewing’s sarcoma, synovial sarcoma and malignant rhabdoid tumors (soft tissue sarcomas), highlighting the more recent results in this field. Finally, we discuss the perspective and challenge of CDK9 modulation in cancer.
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Affiliation(s)
- Matteo Cassandri
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Rossella Fioravanti
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Silvia Pomella
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sergio Valente
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Dante Rotili
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Giada Del Baldo
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Biagio De Angelis
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Rossella Rota
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Antonello Mai
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
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6
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Sun X, Gao H, Yang Y, He M, Wu Y, Song Y, Tong Y, Rao Y. PROTACs: great opportunities for academia and industry. Signal Transduct Target Ther 2019; 4:64. [PMID: 31885879 PMCID: PMC6927964 DOI: 10.1038/s41392-019-0101-6] [Citation(s) in RCA: 354] [Impact Index Per Article: 70.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 11/17/2019] [Accepted: 11/21/2019] [Indexed: 02/07/2023] Open
Abstract
Although many kinds of therapies are applied in the clinic, drug-resistance is a major and unavoidable problem. Another disturbing statistic is the limited number of drug targets, which are presently only 20-25% of all protein targets that are currently being studied. Moreover, the focus of current explorations of targets are their enzymatic functions, which ignores the functions from their scaffold moiety. As a promising and appealing technology, PROteolysis TArgeting Chimeras (PROTACs) have attracted great attention both from academia and industry for finding available approaches to solve the above problems. PROTACs regulate protein function by degrading target proteins instead of inhibiting them, providing more sensitivity to drug-resistant targets and a greater chance to affect the nonenzymatic functions. PROTACs have been proven to show better selectivity compared to classic inhibitors. PROTACs can be described as a chemical knockdown approach with rapidity and reversibility, which presents new and different biology compared to other gene editing tools by avoiding misinterpretations that arise from potential genetic compensation and/or spontaneous mutations. PRTOACs have been widely explored throughout the world and have outperformed not only in cancer diseases, but also in immune disorders, viral infections and neurodegenerative diseases. Although PROTACs present a very promising and powerful approach for crossing the hurdles of present drug discovery and tool development in biology, more efforts are needed to gain to get deeper insight into the efficacy and safety of PROTACs in the clinic. More target binders and more E3 ligases applicable for developing PROTACs are waiting for exploration.
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Affiliation(s)
- Xiuyun Sun
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084 P. R. China
| | - Hongying Gao
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084 P. R. China
| | - Yiqing Yang
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084 P. R. China
| | - Ming He
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
| | - Yue Wu
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
| | - Yugang Song
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
| | - Yan Tong
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
| | - Yu Rao
- Ministry of Education (MOE) Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084 P. R. China
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, 450001 China
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7
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Selective degradation of CDK6 by a palbociclib based PROTAC. Bioorg Med Chem Lett 2019; 29:1375-1379. [PMID: 30935795 DOI: 10.1016/j.bmcl.2019.03.035] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/21/2019] [Accepted: 03/25/2019] [Indexed: 12/28/2022]
Abstract
Development of selective kinase inhibitors that target the ATP binding site continues to be a challenge largely due to similar binding pockets. Palbociclib is a cyclin-dependent kinase inhibitor that targets the ATP binding site of CDK4 and CDK6 with similar potency. The enzymatic function associated with the kinase can be effectively probed using kinase inhibitors however the kinase-independent functions cannot. Herein, we report a palbociclib based PROTAC that selectively degrades CDK6 while sparing the homolog CDK4. We used competition studies to characterize the binding and mechanism of CDK6 degradation.
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8
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Chohan TA, Qayyum A, Rehman K, Tariq M, Akash MSH. An insight into the emerging role of cyclin-dependent kinase inhibitors as potential therapeutic agents for the treatment of advanced cancers. Biomed Pharmacother 2018; 107:1326-1341. [PMID: 30257348 DOI: 10.1016/j.biopha.2018.08.116] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 08/11/2018] [Accepted: 08/23/2018] [Indexed: 01/16/2023] Open
Abstract
Cancer denotes a pathological manifestation that is characterized by hyperproliferation of cells. It has anticipated that a better understanding of disease pathogenesis and the role of cell-cycle regulators may provide an opportunity to develop an effective cancer therapeutic agents. Specifically, the cyclin-dependent kinases (CDKs) which regulate the transition of cell-cycle through different phases; have been identified as fundamental targets for therapeutic advances. It is an evident from experimental studies that several events leading to tumor growth occur by exacerbation of CDK4/CDK6 in G1-phase of cell division cycle. Additionally, the characteristics of S- and G2/M-phase regulated by CDK1/CDK2 are pivotal events that may lead to abrupt the cell division. Although, previously reported CDK inhibitors have shown remarkable results in pre-clinical studies, but have not yielded appreciable clinical results yet. Therefore, the development of clinically potent CDK inhibitors has remained to be a challenging task. However, continuous efforts has led to the development of some novel CDKs inhibitors that have emerged as a potent strategy for the treatment of advanced cancers. In this article, we have summarized the role of CDKs in cell-cycle regulation and tumorigenesis and recent advances in the development of CDKs inhibitors as a promising therapy for the treatment of advanced cancer. In addition, we have also performed a comparison of crystallographic studies to get valuable insight into the interaction mode differences of inhibitors, binding to CDK isoforms with apparently similar binding sites. The knowledge of ligand-specific recognition towards a particular CDK isoform may be applied as a key tool in future for the designing of isoform-specific inhibitors.
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Affiliation(s)
- Tahir Ali Chohan
- Institute of Pharmaceutical Sciences, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Aisha Qayyum
- Department of Paediatrics Medicine, Sabzazar Hospital, Lahore, Pakistan
| | - Kanwal Rehman
- Institute of Pharmacy, Physiology and Pharmacology, University of Agriculture, Faisalabad, Pakistan
| | - Muhammad Tariq
- Faculty of Pharmacy & Alternative Medicine, The Islamia University of Bahawalpur, Pakistan
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9
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Robb CM, Contreras JI, Kour S, Taylor MA, Abid M, Sonawane YA, Zahid M, Murry DJ, Natarajan A, Rana S. Chemically induced degradation of CDK9 by a proteolysis targeting chimera (PROTAC). Chem Commun (Camb) 2018. [PMID: 28636052 DOI: 10.1039/c7cc03879h] [Citation(s) in RCA: 162] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cyclin-dependent kinase 9 (CDK9), a member of the cyclin-dependent protein kinase (CDK) family, is involved in transcriptional elongation of several target genes. CDK9 is ubiquitously expressed and has been shown to contribute to a variety of malignancies such as pancreatic, prostate and breast cancers. Here we report the development of a heterobifunctional small molecule proteolysis targeting chimera (PROTAC) capable of cereblon (CRBN) mediated proteasomal degradation of CDK9. In HCT116 cells, it selectively degrades CDK9 while sparing other CDK family members. This is the first example of a PROTAC that selectively degrades CDK9.
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Affiliation(s)
- Caroline M Robb
- Eppley Institute for Research in Cancer and Allied Diseases, Omaha, Nebraska 68022, USA.
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10
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Franco LC, Morales F, Boffo S, Giordano A. CDK9: A key player in cancer and other diseases. J Cell Biochem 2017; 119:1273-1284. [PMID: 28722178 DOI: 10.1002/jcb.26293] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 07/18/2017] [Indexed: 02/06/2023]
Abstract
Cyclin-Dependent Kinase 9 (CDK9) is part of a functional diverse group of enzymes responsible for cell cycle control and progression. It associates mainly with Cyclin T1 and forms the Positive Transcription Elongation Factor b (p-TEFb) complex responsible for regulation of transcription elongation and mRNA maturation. Recent studies have highlighted the importance of CDK9 in many relevant pathologic processes, like cancer, cardiovascular diseases, and viral replication. Herein we provide an overview of the different pathways in which CDK9 is directly and indirectly involved.
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Affiliation(s)
- Lia Carolina Franco
- Escuela de Medicina, Universidad de las Americas (UDLA), Quito, Ecuador.,Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, College of Science and Technology, Temple University, PA, Pennsylvania
| | - Fátima Morales
- Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, College of Science and Technology, Temple University, PA, Pennsylvania.,Departamento de Química Orgánica, Universidad de Murcia, Murcia, Spain
| | - Silvia Boffo
- Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, College of Science and Technology, Temple University, PA, Pennsylvania
| | - Antonio Giordano
- Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, College of Science and Technology, Temple University, PA, Pennsylvania.,Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
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11
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Abstract
Cyclin-dependent kinase 9 (CDK9), a subunit of the positive transcription elongation factor b (P-TEFb) complex, regulates gene transcription elongation by phosphorylating the C-terminal domain (CTD) of RNA polymerase II (RNAPII). The deregulation of CDK9/P-TEFb has important implications for many cancer types. BAY 1143572 is a novel and highly selective CDK9/P-TEFb inhibitor currently being investigated in phase 1 studies. We evaluated the therapeutic potential of BAY 1143572 in adult T-cell leukemia/lymphoma (ATL). As a result of CDK9 inhibition and subsequent inhibition of phosphorylation at serine 2 of the RNAPII CTD, BAY 1143572 decreased c-Myc and Mcl-1 levels in ATL-derived or human T-cell lymphotropic virus type-1 (HTLV-1)-transformed lines and primary ATL cells tested, leading to their growth inhibition and apoptosis. Median inhibitory concentrations for BAY 1143572 in ATL-derived or HTLV-1-transformed lines (n = 8), primary ATL cells (n = 11), and CD4+ cells from healthy volunteers (n = 5) were 0.535, 0.30, and 0.36 μM, respectively. Next, NOG mice were used as recipients of tumor cells from an ATL patient. BAY 1143572-treated ATL-bearing mice (once daily 12.5 mg/kg oral application) demonstrated significantly decreased ATL cell infiltration of the liver and bone marrow, as well as decreased human soluble interleukin-2 receptor levels in serum (reflecting the ATL tumor burden), compared with untreated mice (n = 8 for both). BAY 1143572-treated ATL-bearing mice demonstrated significantly prolonged survival compared with untreated ATL-bearing mice (n = 7 for both). Collectively, this study indicates that BAY 1143572 showed strong potential as a novel treatment of ATL.
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12
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Han Y, Zhao S, Gong Y, Hou G, Li X, Li L. Serum cyclin-dependent kinase 9 is a potential biomarker of atherosclerotic inflammation. Oncotarget 2016; 7:1854-62. [PMID: 26636538 PMCID: PMC4811502 DOI: 10.18632/oncotarget.6443] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/16/2015] [Indexed: 11/25/2022] Open
Abstract
Atherosclerotic coronary artery disease (CAD) is one of the most prevalent diseases worldwide. Atherosclerosis was considered to be the single most important contributor to CAD. In this study, a distinct serum protein expression pattern in CAD patients was demonstrated by proteomic analysis with two-dimensional gel electrophoresis coupled with mass spectrometry. In particular, CDK9 was found to be highly elevated in serum, monocytes and artery plaque samples of CAD patients. Furthermore, there was high infiltration of CD14+ monocytes/macrophages within artery plaques correlated with the expression of CDK9. Moreover, Flavopiridol (CDK9 inhibitor) could inhibit THP-1 cell (monocytic acute leukemia cell line) proliferation by targeting CDK9. Altogether, These findings indicate that CDK9 represent an important role for inflammation in the pathogenesis of atherosclerosis. It may be a potential biomarker of atherosclerotic inflammation and offer insights into the pathophysiology and targeted therapy for atherosclerotic CAD.
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Affiliation(s)
- Yeming Han
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Department of of Cardiology, Qilu Hospital, Shandong University, Jinan, Shandong, 250012, China
| | - Shanshan Zhao
- Laboratory of Experimental Teratology, Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Yaoqin Gong
- Laboratory of Experimental Teratology, Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, 250012, China.,Department of Genetics, School of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Guihua Hou
- Laboratory of Experimental Teratology, Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Xi Li
- Laboratory of Experimental Teratology, Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, 250012, China.,Department of Genetics, School of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Li Li
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Department of of Cardiology, Qilu Hospital, Shandong University, Jinan, Shandong, 250012, China
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13
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Peyressatre M, Prével C, Pellerano M, Morris MC. Targeting cyclin-dependent kinases in human cancers: from small molecules to Peptide inhibitors. Cancers (Basel) 2015; 7:179-237. [PMID: 25625291 PMCID: PMC4381256 DOI: 10.3390/cancers7010179] [Citation(s) in RCA: 219] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 01/12/2015] [Indexed: 12/12/2022] Open
Abstract
Cyclin-dependent kinases (CDK/Cyclins) form a family of heterodimeric kinases that play central roles in regulation of cell cycle progression, transcription and other major biological processes including neuronal differentiation and metabolism. Constitutive or deregulated hyperactivity of these kinases due to amplification, overexpression or mutation of cyclins or CDK, contributes to proliferation of cancer cells, and aberrant activity of these kinases has been reported in a wide variety of human cancers. These kinases therefore constitute biomarkers of proliferation and attractive pharmacological targets for development of anticancer therapeutics. The structural features of several of these kinases have been elucidated and their molecular mechanisms of regulation characterized in depth, providing clues for development of drugs and inhibitors to disrupt their function. However, like most other kinases, they constitute a challenging class of therapeutic targets due to their highly conserved structural features and ATP-binding pocket. Notwithstanding, several classes of inhibitors have been discovered from natural sources, and small molecule derivatives have been synthesized through rational, structure-guided approaches or identified in high throughput screens. The larger part of these inhibitors target ATP pockets, but a growing number of peptides targeting protein/protein interfaces are being proposed, and a small number of compounds targeting allosteric sites have been reported.
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Affiliation(s)
- Marion Peyressatre
- Institut des Biomolécules Max Mousseron, IBMM-CNRS-UMR5247, 15 Av. Charles Flahault, 34093 Montpellier, France.
| | - Camille Prével
- Institut des Biomolécules Max Mousseron, IBMM-CNRS-UMR5247, 15 Av. Charles Flahault, 34093 Montpellier, France.
| | - Morgan Pellerano
- Institut des Biomolécules Max Mousseron, IBMM-CNRS-UMR5247, 15 Av. Charles Flahault, 34093 Montpellier, France.
| | - May C Morris
- Institut des Biomolécules Max Mousseron, IBMM-CNRS-UMR5247, 15 Av. Charles Flahault, 34093 Montpellier, France.
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14
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Li CF, Fang FM, Lan J, Wang JW, Kung HJ, Chen LT, Chen TJ, Li SH, Wang YH, Tai HC, Yu SC, Huang HY. AMACR amplification in myxofibrosarcomas: a mechanism of overexpression that promotes cell proliferation with therapeutic relevance. Clin Cancer Res 2014; 20:6141-52. [PMID: 25384383 DOI: 10.1158/1078-0432.ccr-14-1182] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Myxofibrosarcomas frequently display arm-level gains on 5p. We characterized the pathogenetic and therapeutic relevance of the α-methylacyl coenzyme A racemase (AMACR) at 5p13.3. EXPERIMENTAL DESIGN AMACR mRNA expression in myxofibrosarcomas was analyzed using the public transcriptome and laser-microdissected sarcoma cells. We performed florescence in situ hybridization (FISH) and immunohistochemistry in independent samples for clinical correlates. In AMACR-overexpressing myxofibrosarcoma cells and xenografts, we elucidated the biologic function of AMACR using RNA interference and explored the therapeutic effect and mechanism of an AMACR inhibitor, ebselen oxide. RESULTS AMACR protein overexpression and gene amplification were significantly associated with each other (P < 0.001), with higher tumor grades (both P ≤ 0.002), and univariately with worse metastasis-free survival (MFS; both P < 0.0001) and disease-specific survival (DSS; P = 0.0002 for overexpression; P = 0.0062 for amplification). AMACR protein overexpression also independently portended adverse outcome (DSS, P = 0.007; MFS, P = 0.001). However, 39% of AMACR-overexpression cases did not show gene amplification, implying alternative regulatory mechanisms. In myxofibrosarcoma cell lines, stable AMACR knockdown suppressed cell proliferation, anchorage-independent growth, and expression of cyclin D1 and cyclin T2. These growth-promoting attributes of AMACR were corroborated in the AMACR-silenced xenograft model and AMACR-underexpressed myxofibrosarcomas, showing decreased labeling for cyclin D1, cyclin T2, and Ki-67. Compared with fibroblasts, AMACR-expressing myxofibrosarcoma cells were more susceptible to ebselen oxide, which not only decreased viable cells, promoted proteasome-mediated degradation of AMACR protein, and induced cellular apoptosis in vitro, but also dose-dependently suppressed xenografted tumor growth in vivo. CONCLUSIONS Overexpressed AMACR in myxofibrosarcomas can be amplification-driven, associated with tumor aggressiveness, and may be relevant as a druggable target.
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Affiliation(s)
- Chien-Feng Li
- Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan. Institute of Clinical Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan. Department of Biotechnology, Southern Taiwan University, Tainan, Taiwan
| | - Fu-Min Fang
- Department of Radiation Oncology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Jui Lan
- Department of Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Jun-Wen Wang
- Department of Orthopedic Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Hsing-Jien Kung
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Tainan, Taiwan
| | - Li-Tzong Chen
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan
| | - Tzu-Ju Chen
- Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan
| | - Shau-Hsuan Li
- Division of Oncology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Yu-Hui Wang
- Institute of Biosignal Transduction, National Cheng Kung University, Tainan, Taiwan
| | - Hui-Chun Tai
- Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan
| | - Shih-Chen Yu
- Department of Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Hsuan-Ying Huang
- Department of Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
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15
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Wang L, Gao W, Hu F, Xu Z, Wang F. MicroRNA-874 inhibits cell proliferation and induces apoptosis in human breast cancer by targeting CDK9. FEBS Lett 2014; 588:4527-35. [PMID: 25281924 DOI: 10.1016/j.febslet.2014.09.035] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 09/05/2014] [Accepted: 09/05/2014] [Indexed: 01/28/2023]
Abstract
It has been demonstrated that miR-874 plays important roles in many types of cancers. Nevertheless, its biological function in breast cancer remains largely unknown. In this study, we found that the expression level of miR-874 is down-regulated in breast cancer in comparison with the adjacent normal tissues. The overexpression of miR-874 is able to inhibit cell proliferation and induce cell apoptosis and cell cycle arrest in MCF7 and MDA-MB-231 cells. Using a bioinformatics method, we further show that CDK9 is a direct target of miR-874 and that its protein level is negatively regulated by miR-874. Therefore, the data reported in this manuscript demonstrate that miR-874 is an important regulator in breast cancer and imply that the miR-874/CDK9 axis has potential as a therapeutic target for breast cancer.
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Affiliation(s)
- Ling Wang
- Analytical & Testing Center, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Wen Gao
- Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Fan Hu
- Analytical & Testing Center, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Zhiyang Xu
- Analytical & Testing Center, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Fuqiang Wang
- Analytical & Testing Center, Nanjing Medical University, Nanjing, Jiangsu 210029, China.
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16
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Dai Q, Luan G, Deng L, Lei T, Kang H, Song X, Zhang Y, Xiao ZX, Li Q. Primordial dwarfism gene maintains Lin28 expression to safeguard embryonic stem cells from premature differentiation. Cell Rep 2014; 7:735-46. [PMID: 24768001 DOI: 10.1016/j.celrep.2014.03.053] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 01/15/2014] [Accepted: 03/20/2014] [Indexed: 01/09/2023] Open
Abstract
Primordial dwarfism (PD) is characterized by global growth failure, both during embryogenesis and postnatally. Loss-of-function germline mutations in La ribonucleoprotein domain family, member 7 (LAPR7) have recently been linked to PD. Paradoxically, LARP7 deficiency was previously assumed to be associated with increased cell growth and proliferation via activation of positive transcription elongation factor b (P-TEFb). Here, we show that Larp7 deficiency likely does not significantly increase P-TEFb activity. We further discover that Larp7 knockdown does not affect pluripotency but instead primes embryonic stem cells (ESCs) for differentiation via downregulation of Lin28, a positive regulator of organismal growth. Mechanistically, we show that Larp7 interacts with a poly(A) polymerase Star-PAP to maintain Lin28 mRNA stability. We propose that proper regulation of Lin28 and PTEFb is essential for embryonic cells to achieve a sufficient number of cell divisions prior to differentiation and ultimately to maintain proper organismal size.
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Affiliation(s)
- Qian Dai
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Guangxin Luan
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Li Deng
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Tingjun Lei
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Han Kang
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Xu Song
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Yujun Zhang
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Zhi-Xiong Xiao
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China
| | - Qintong Li
- Center of Growth, Metabolism, and Aging, Key Laboratory of Bio-Resources and Eco-Environment, and State Key Laboratory of Biotherapy, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China.
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17
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Deregulations in the cyclin-dependent kinase-9-related pathway in cancer: implications for drug discovery and development. ISRN ONCOLOGY 2013; 2013:305371. [PMID: 23840966 PMCID: PMC3690251 DOI: 10.1155/2013/305371] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 05/19/2013] [Indexed: 12/21/2022]
Abstract
The CDK9-related pathway is an important regulator of mammalian cell biology and is also involved in the replication cycle of several viruses, including the human immunodeficiency virus type 1. CDK9 is present in two isoforms termed CDK9-42 and CDK9-55 that bind noncovalently type T cyclins and cyclin K. This association forms a heterodimer, where CDK9 carries the enzymatic site and the cyclin partner functions as a regulatory subunit. This heterodimer is the main component of the positive transcription elongation factor b, which stabilizes RNA elongation via phosphorylation of the RNA pol II carboxyl terminal domain. Abnormal activities in the CDK9-related pathway were observed in human malignancies and cardiac hypertrophies. Thus, the elucidation of the CDK9 pathway deregulations may provide useful insights into the pathogenesis and progression of human malignancies, cardiac hypertrophy, AIDS and other viral-related maladies. These studies may lead to the improvement of kinase inhibitors for the treatment of the previously mentioned pathological conditions. This review describes the CDK9-related pathway deregulations in malignancies and the development of kinase inhibitors in cancer therapy, which can be classified into three categories: antagonists that block the ATP binding site of the catalytic domain, allosteric inhibitors, and small molecules that disrupt protein-protein interactions.
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18
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Marchesi I, Nieddu V, Caracciolo V, Maioli M, Gaspa L, Giordano A, Bagella L. Activation and function of murine Cyclin T2A and Cyclin T2B during skeletal muscle differentiation. J Cell Biochem 2013; 114:728-34. [DOI: 10.1002/jcb.24414] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 09/28/2012] [Indexed: 12/14/2022]
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19
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Caracciolo V, Laurenti G, Romano G, Carnevale V, Cimini AM, Crozier-Fitzgerald C, Gentile Warschauer E, Russo G, Giordano A. Flavopiridol induces phosphorylation of AKT in a human glioblastoma cell line, in contrast to siRNA-mediated silencing of Cdk9: Implications for drug design and development. Cell Cycle 2012; 11:1202-16. [PMID: 22391209 DOI: 10.4161/cc.11.6.19663] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Cdk9 and Cdk7 are cdc2-like serine/threonine kinases that stabilize RNA transcript elongation through RNA polII carboxyl terminal domain (CTD) phosphorylation and are considered suitable targets for cancer therapy. The effects of flavopiridol and of siRNA-mediated inhibition of Cdk9 and/or Cdk7 were analyzed in human glioblastoma and human prostate cancer cell lines. One finding revealed that Cdk9 and Cdk7 could substitute each other in RNA polII CTD phosphorylation in contrast to the in vitro system. Thus, a simultaneous inhibition of Cdk9 and Cdk7 might be required both for targeting malignant cells and developing a platform for microarray analysis. However, these two pathways are not redundant, as indicated by differential effects observed in cell cycle regulation following siRNA-mediated inhibition of Cdk9 and/or Cdk7 in human PC3 prostate cancer cell line. Specifically, siRNA-mediated inhibition of Cdk9 caused a shift from G 0/G 1 to G 2/M phase in human PC3 prostate cancer cell line. Another finding showed that flavopiridol treatment induced a substantial AKT-Ser473 phosphorylation in human glioblastoma T98G cell line in contrast to siRNA-mediated inhibition of Cdk9 and Cdk9 combined with Cdk7, whereas siRNA-mediated silencing of Cdk7 caused a minor increase in AKT-Ser473 phosphorylation. AKT-Ser473 is a hallmark of AKT pathway activation and may protect cells from apoptosis. This finding also shows that Cdk9 and Cdk7 pathways are not redundant and may have important implications in drug development and for studying the mechanism of chemoresistance in malignant cells.
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Affiliation(s)
- Valentina Caracciolo
- Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA
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20
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Moiola C, De Luca P, Gardner K, Vazquez E, De Siervi A. Cyclin T1 overexpression induces malignant transformation and tumor growth. Cell Cycle 2010; 9:3119-26. [PMID: 20714219 DOI: 10.4161/cc.9.15.12526] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Human PTE Fb is a protein kinase composed by CDK9 and Cyclin T that controls the elongation phase of RNA Pol II. This complex also affects the activation and differentiation program of lymphoid cells. In this study we found that several head and neck tumor cell lines overexpress PTE Fb. We also established that Cyclin T1 is able to induce transformation in vitro, as we determined by foci and colony formation assays. Nu/nu mice s.c. injected with stable transfected Cyclin T1 cells (NIH 3T3 Cyclin T1) developed tumors faster than animals injected with control cells (NIH 3T3 beta-gal). In vitro, NIH 3T3 Cyclin T1 cells show increased proliferation and CDK4-Rb phosphorylation. Even more, silencing E2F1 expression (shRNA E2F1) in NIH 3T3 cells resulted in a dramatic inhibition of Cyclin T1-induced foci. All these data demonstrate for the first time the Cyclin T1 oncogenic function and suggest a role for this protein in controlling cell cycle probably via Rb/E2F1 pathway.
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Affiliation(s)
- Cristian Moiola
- Department of Biological Chemistry, School of Sciences, University of Buenos Aires, Buenos Aires, Argentina
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21
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Giacinti C, Musarò A, De Falco G, Jourdan I, Molinaro M, Bagella L, Simone C, Giordano A. Cdk9-55: a new player in muscle regeneration. J Cell Physiol 2008; 216:576-82. [PMID: 18546201 DOI: 10.1002/jcp.21361] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adult skeletal muscle contains a specialized population of myogenic quiescent stem cells, termed satellite cells, which contribute to repair myofibers after injury. During muscle regeneration, satellite cells exit their normal quiescent state, proliferate, activating MyoD and Myf-5 expression, and finally differentiate and fuse to reconstitute the injured muscle architecture. We have previously reported that cdk9 is required for myogenesis in vitro by activating MyoD-dependent transcription. In myoblasts induced to differentiate, MyoD recruits cdk9 on the chromatin of muscle-specific regulatory regions. This event correlates with chromatin-modifying enzyme recruitment and phosphorylation of cdk9-specific target residues at the carboxyl-terminal domain of RNA polymerase II. Here we report that a second cdk9 isoform, termed cdk9-55, plays a fundamental role in muscle regeneration and differentiation in vivo. This alternative form is specifically induced in injured myofibers and its activity is strictly required for the completion of muscle regeneration process.
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Affiliation(s)
- Cristina Giacinti
- Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, USA
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22
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Chiacchiera F, Simone C. Signal-dependent regulation of gene expression as a target for cancer treatment: inhibiting p38alpha in colorectal tumors. Cancer Lett 2008; 265:16-26. [PMID: 18395970 DOI: 10.1016/j.canlet.2008.02.061] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Revised: 02/15/2008] [Accepted: 02/19/2008] [Indexed: 12/27/2022]
Abstract
In the last year, several evidences indicated that pharmacological manipulation of relevant signaling pathways could selectively affect gene expression to influence cell fate. These findings render of extreme importance the elucidation of how external stimuli are transduced to mediate chromatin modifications, resulting in a permissive or repressive environment for gene expression. These signaling cascades activate or repress the function of chromatin binding proteins that represent attractive pharmacological targets for human diseases. Actually, the closer the target is to chromatin, the more the transcriptional effect will be selective. Recent studies suggest that pharmacological manipulation of signaling pathways to modulate cell fate is indeed possible and that chromatin-associated kinases could represent an optimal target. The p38 MAPK is the prototype of this class of enzymes and its central role in the transcription process is evolutionary conserved. In this review we will focus on the possibility to inhibit p38alpha in colorectal cancer to arrest tumor progression and induce autophagic cell death.
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Affiliation(s)
- Fulvio Chiacchiera
- Laboratory of Signal-dependent Transcription, Department of Translational Pharmacology (DTP), Consorzio Mario Negri Sud, Via Nazionale 8/A, 66030 Santa Maria Imbaro (Chieti), Italy
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