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Sancho M, Leiva D, Lucendo E, Orzáez M. Understanding MCL1: from cellular function and regulation to pharmacological inhibition. FEBS J 2022; 289:6209-6234. [PMID: 34310025 PMCID: PMC9787394 DOI: 10.1111/febs.16136] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 07/09/2021] [Accepted: 07/22/2021] [Indexed: 12/30/2022]
Abstract
Myeloid cell leukemia-1 (MCL1), an antiapoptotic member of the BCL2 family characterized by a short half-life, functions as a rapid sensor that regulates cell death and other relevant processes that include cell cycle progression and mitochondrial homeostasis. In cancer, MCL1 overexpression contributes to cell survival and resistance to diverse chemotherapeutic agents; for this reason, several MCL1 inhibitors are currently under preclinical and clinical development for cancer treatment. However, the nonapoptotic functions of MCL1 may influence their therapeutic potential. Overall, the complexity of MCL1 regulation and function represent challenges to the clinical application of MCL1 inhibitors. We now summarize the current knowledge regarding MCL1 structure, regulation, and function that could impact the clinical success of MCL1 inhibitors.
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Affiliation(s)
- Mónica Sancho
- Targeted Therapies on Cancer and Inflammation LaboratoryCentro de Investigación Príncipe FelipeValenciaSpain
| | - Diego Leiva
- Targeted Therapies on Cancer and Inflammation LaboratoryCentro de Investigación Príncipe FelipeValenciaSpain
| | - Estefanía Lucendo
- Targeted Therapies on Cancer and Inflammation LaboratoryCentro de Investigación Príncipe FelipeValenciaSpain
| | - Mar Orzáez
- Targeted Therapies on Cancer and Inflammation LaboratoryCentro de Investigación Príncipe FelipeValenciaSpain
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2
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Rahimi HM, Nemati S, Alavifard H, Baghaei K, Mirjalali H, Zali MR. Soluble total antigen derived from Toxoplasma gondii RH strain prevents apoptosis, but induces anti-apoptosis in human monocyte cell line. Folia Parasitol (Praha) 2021; 68. [PMID: 34889779 DOI: 10.14411/fp.2021.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 08/24/2021] [Indexed: 11/19/2022]
Abstract
Apoptosis plays crucial role in the pathogenesis of toxoplasmosis, as it limits further development of the disease. The current study aimed to investigate the effects of different concentrations of soluble total antigen (STAg) of Toxoplasma gondii (Nicolle et Manceaux, 1908) on the apoptotic and anti-apoptotic pathways. PMA-activated THP-1 cell line was sensed by T. gondii STAg and the expression patterns of caspase-3, -7, -8, -9, Bax, Bcl-2, and Mcl-1 genes were evaluated. The results showed statistically significant concentration-dependent overexpression of both Bcl-2 (P-value < 0.0001) and Mcl-1 (P-value = 0.0147). The cas-7 showed overexpression in all concentrations (P-value < 0.0001). The cas-3 was suppressed in concentrations 100, 80, and 40 µg, but statistically significant downregulated in concentrations 10 and 20 µg. The Bax was suppressed in concentrations 100 to 20 µg, while it slightly downregulated 1.42 fold (P-value = 0.0029) in concentration 10 µg. The expression of cas-8 and -9 was suppressed in all concentrations. Our results indicated that T. gondii STAg downregulated and suppressed apoptotic and upregulated anti-apoptotic pathways. The upregulation of cas-7 in this study may indicate the role of T. gondii STAg in activation of inflammatory responses.
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Affiliation(s)
- Hanieh Mohammad Rahimi
- Foodborne and Waterborne Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sara Nemati
- Foodborne and Waterborne Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Helia Alavifard
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kaveh Baghaei
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hamed Mirjalali
- Foodborne and Waterborne Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Zali
- Gastroenterology and Liver Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran *Address for correspondence: Hamed Mirjalali, Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Arabi Street, 1985717413, Chamran Highway, Tehran, Iran.
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3
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de Witte CJ, Espejo Valle-Inclan J, Hami N, Lõhmussaar K, Kopper O, Vreuls CPH, Jonges GN, van Diest P, Nguyen L, Clevers H, Kloosterman WP, Cuppen E, Snippert HJG, Zweemer RP, Witteveen PO, Stelloo E. Patient-Derived Ovarian Cancer Organoids Mimic Clinical Response and Exhibit Heterogeneous Inter- and Intrapatient Drug Responses. Cell Rep 2021; 31:107762. [PMID: 32553164 DOI: 10.1016/j.celrep.2020.107762] [Citation(s) in RCA: 143] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/26/2020] [Accepted: 05/21/2020] [Indexed: 01/19/2023] Open
Abstract
There remains an unmet need for preclinical models to enable personalized therapy for ovarian cancer (OC) patients. Here we evaluate the capacity of patient-derived organoids (PDOs) to predict clinical drug response and functional consequences of tumor heterogeneity. We included 36 whole-genome-characterized PDOs from 23 OC patients with known clinical histories. OC PDOs maintain the genomic features of the original tumor lesion and recapitulate patient response to neoadjuvant carboplatin/paclitaxel combination treatment. PDOs display inter- and intrapatient drug response heterogeneity to chemotherapy and targeted drugs, which can be partially explained by genetic aberrations. PDO drug screening identifies high responsiveness to at least one drug for 88% of patients. PDOs are valuable preclinical models that can provide insights into drug response for individual patients with OC, complementary to genetic testing. Generating PDOs of multiple tumor locations can improve clinical decision making and increase our knowledge of genetic and drug response heterogeneity.
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Affiliation(s)
- Chris Jenske de Witte
- Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands
| | - Jose Espejo Valle-Inclan
- Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands
| | - Nizar Hami
- Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands; Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Kadi Lõhmussaar
- Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands; Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Oded Kopper
- Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands; Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Celien Philomena Henrieke Vreuls
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Geertruida Nellie Jonges
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Paul van Diest
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Luan Nguyen
- Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands
| | - Hans Clevers
- Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands; Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Wigard Pieter Kloosterman
- Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Edwin Cuppen
- Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands; Hartwig Medical Foundation, Science Park 408, 1098 XH Amsterdam, the Netherlands
| | - Hugo Johannes Gerhardus Snippert
- Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands; Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Ronald Peter Zweemer
- Division of Imaging and Oncology, Department of Gynecological Oncology, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Petronella Oda Witteveen
- Department of Medical Oncology, Cancer Center, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Ellen Stelloo
- Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521 AL Utrecht, the Netherlands.
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4
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Li X, Jiang Y, Peterson YK, Xu T, Himes RA, Luo X, Yin G, Inks ES, Dolloff N, Halene S, Chan SSL, Chou CJ. Design of Hydrazide-Bearing HDACIs Based on Panobinostat and Their p53 and FLT3-ITD Dependency in Antileukemia Activity. J Med Chem 2020; 63:5501-5525. [PMID: 32321249 DOI: 10.1021/acs.jmedchem.0c00442] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Here, we present a new series of hydrazide-bearing class I selective HDAC inhibitors designed based on panobinostat. The cap, linker, and zinc-binding group were derivatized to improve HDAC affinity and antileukemia efficacy. Lead inhibitor 13a shows picomolar or low nanomolar IC50 values against HDAC1 and HDAC3 and exhibits differential toxicity profiles toward multiple cancer cells with different FLT3 and p53 statuses. 13a indirectly inhibits the FLT3 signaling pathway and down-regulates master antiapoptotic proteins, resulting in the activation of pro-caspase3 in wt-p53 FLT3-ITD MV4-11 cells. While in the wt-FLT3 and p53-null cells, 13a is incapable of causing apoptosis at a therapeutic concentration. The MDM2 antagonist and the proteasome inhibitor promote 13a-triggered apoptosis by preventing p53 degradation. Furthermore, we demonstrate that apoptosis rather than autophagy is the key contributing factor for 13a-triggered cell death. When compared to panobinostat, 13a is not mutagenic and displays superior in vivo bioavailability and a higher AUC0-inf value.
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Affiliation(s)
- Xiaoyang Li
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266071, China.,Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, Medical University of South Carolina, Charleston, South Carolina 29425, United States
| | - Yuqi Jiang
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266071, China
| | - Yuri K Peterson
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, Medical University of South Carolina, Charleston, South Carolina 29425, United States
| | - Tongqiang Xu
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266071, China
| | - Richard A Himes
- Department of Chemistry and Biochemistry, College of Charleston, 66 George Street, Charleston, South Carolina 29424, United States
| | - Xin Luo
- Technology Center of Qingdao Customs, Qingdao, Shandong 266002, China
| | - Guilin Yin
- Technology Center of Qingdao Customs, Qingdao, Shandong 266002, China
| | - Elizabeth S Inks
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, Medical University of South Carolina, Charleston, South Carolina 29425, United States
| | - Nathan Dolloff
- Department of Cellular and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston SC29425, United States
| | - Stephanie Halene
- Section of Hematology, Department of Internal Medicine and Yale Cancer Center, Yale University School of Medicine, New Haven, Connecticut 06511, United States
| | - Sherine S L Chan
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, Medical University of South Carolina, Charleston, South Carolina 29425, United States
| | - C James Chou
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, Medical University of South Carolina, Charleston, South Carolina 29425, United States
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5
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Saga of Mcl-1: regulation from transcription to degradation. Cell Death Differ 2020; 27:405-419. [PMID: 31907390 DOI: 10.1038/s41418-019-0486-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/05/2019] [Accepted: 12/13/2019] [Indexed: 01/01/2023] Open
Abstract
The members of the Bcl-2 family are the central regulators of various cell death modalities. Some of these proteins contribute to apoptosis, while others counteract this type of programmed cell death, thus balancing cell demise and survival. A disruption of this balance leads to the development of various diseases, including cancer. Therefore, understanding the mechanisms that underlie the regulation of proteins of the Bcl-2 family is of great importance for biomedical research. Among the members of the Bcl-2 family, antiapoptotic protein Mcl-1 is characterized by a short half-life, which renders this protein highly sensitive to changes in its synthesis or degradation. Hence, the regulation of Mcl-1 is of particular scientific interest, and the study of Mcl-1 modulators could aid in the understanding of the mechanisms of disease development and the ways of their treatment. Here, we summarize the present knowledge regarding the regulation of Mcl-1, from transcription to degradation, focusing on aspects that have not yet been described in detail.
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6
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Histone Deacetylase Inhibitors Enhance Cell Killing and Block Interferon-Beta Synthesis Elicited by Infection with an Oncolytic Parainfluenza Virus. Viruses 2019; 11:v11050431. [PMID: 31083335 PMCID: PMC6563284 DOI: 10.3390/v11050431] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 12/28/2022] Open
Abstract
Previous results have shown that infection with the cytoplasmic-replicating parainfluenza virus 5 mutant P/V-CPI- sensitizes cells to DNA damaging agents, resulting in the enhanced killing of airway cancer cells. Here, we have tested the hypothesis that histone deacetylase (HDAC) inhibitors can also act with P/V-CPI- infection to enhance cancer cell killing. Using human small cell lung cancer and laryngeal cancer cell lines, 10 HDAC inhibitors were tested for their effect on viability of P/V-CPI- infected cells. HDAC inhibitors such as scriptaid enhanced caspase-3/7, -8 and -9 activity induced by P/V-CPI- and overall cell toxicity. Scriptaid-mediated enhanced killing was eliminated in lung cancer cells that were engineered to express a protein which sequesters double stranded RNA. Scriptaid also enhanced cancer cell killing by two other negative strand RNA viruses - the La Crosse virus and vesicular stomatitis virus. Scriptaid treatment enhanced the spread of the P/V-CPI- virus through a population of cancer cells, and suppressed interferon-beta induction through blocking phosphorylation and nuclear translocation of Interferon Regulatory Factor 3 (IRF-3). Taken together, these data support a role for combinations of a cytoplasmic-replicating RNA virus such as the P/V-CPI- mutant along with chemotherapeutic agents.
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7
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Kadia TM, Kantarjian HM, Konopleva M. Myeloid cell leukemia-1 dependence in acute myeloid leukemia: a novel approach to patient therapy. Oncotarget 2019; 10:1250-1265. [PMID: 30815228 PMCID: PMC6383813 DOI: 10.18632/oncotarget.26579] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 12/16/2018] [Indexed: 12/15/2022] Open
Abstract
Acute myeloid leukemia (AML) is the most common form of acute leukemia in adults, affecting approximately 21,000 people annually (nearly 11,000 deaths) in the United States. B-cell lymphoma 2 (BCL-2) family proteins, notably myeloid cell leukemia-1 (MCL-1), have been associated with both the development and persistence of AML. MCL-1 is one of the predominant BCL-2 family members expressed in samples from patients with untreated AML. MCL-1 is a critical cell survival factor for cancer and contributes to chemotherapy resistance by directly affecting cell death pathways. Here, we review the role of MCL-1 in AML and the mechanisms by which the potent cyclin-dependent kinase 9 inhibitor alvocidib, through regulation of MCL-1, may serve as a rational therapeutic approach against the disease.
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Affiliation(s)
| | | | - Marina Konopleva
- The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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8
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Abstract
Despite the success of antiretroviral therapy (ART), there is currently no HIV cure and treatment is life long. HIV persists during ART due to long-lived and proliferating latently infected CD4+ T cells. One strategy to eliminate latency is to activate virus production using latency reversing agents (LRAs) with the goal of triggering cell death through virus-induced cytolysis or immune-mediated clearance. However, multiple studies have demonstrated that activation of viral transcription alone is insufficient to induce cell death and some LRAs may counteract cell death by promoting cell survival. Here, we review new approaches to induce death of latently infected cells through apoptosis and inhibition of pathways critical for cell survival, which are often hijacked by HIV proteins. Given advances in the commercial development of compounds that induce apoptosis in cancer chemotherapy, these agents could move rapidly into clinical trials, either alone or in combination with LRAs, to eliminate latent HIV infection.
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9
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Liao Y, Niu X, Chen B, Edwards H, Xu L, Xie C, Lin H, Polin L, Taub JW, Ge Y, Qin Z. Synthesis and Antileukemic Activities of Piperlongumine and HDAC Inhibitor Hybrids against Acute Myeloid Leukemia Cells. J Med Chem 2016; 59:7974-90. [PMID: 27505848 PMCID: PMC6878111 DOI: 10.1021/acs.jmedchem.6b00772] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Synergistic-to-additive antileukemic interactions of piperlongumine (PL) and HDAC inhibitor (HDACi) SAHA (Vorinostat) provide a compelling rationale to construct PL-HDACi hybrids, such as 1-58, which recapitulated the synergism between the parental compounds in high-risk and chemoresistant AML cells. Both PL and HDACi components, either in combination or in hybrid molecules, are essential for inducing significant DNA damage and apoptosis. Introducing C2-chloro substituent to 1-58 yielded 3-35 with increased cytotoxicity but decreased selectivity in noncancerous MCF-10A cells; eliminating C7-C8 olefin of PL obtained 3-31/3-98 scaffolds which were still more active than PL or SAHA in AML and were well-tolerated by MCF-10A cells. The HDACi function was crucial for modulating expression of DNA repair and apoptosis-related proteins. Collectively, PL and SAHA hybrids are potent, multifunctional anti-AML agents, acting in part, by interfering cellular GSH defense, suppressing expression of DNA repair and pro-survival proteins, and inducing expression of pro-apoptotic proteins.
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Affiliation(s)
- Yi Liao
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, United States
| | - Xiaojia Niu
- Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- School of Life Sciences, Jilin University, Changchun 130012, P.R. China
| | - Bailing Chen
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, United States
| | - Holly Edwards
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
| | - Liping Xu
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, United States
| | - Chengzhi Xie
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
| | - Hai Lin
- Department of Hematology and Oncology, The First Hospital of Jilin University, Changchun, P.R. China
| | - Lisa Polin
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
| | - Jeffrey W. Taub
- Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
- Division of Pediatric Hematology/Oncology, Children’s Hospital of Michigan, Detroit, Michigan 48201, United States
| | - Yubin Ge
- Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
| | - Zhihui Qin
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, United States
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
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10
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Shafer D, Grant S. Update on rational targeted therapy in AML. Blood Rev 2016; 30:275-83. [PMID: 26972558 PMCID: PMC4956515 DOI: 10.1016/j.blre.2016.02.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 01/26/2016] [Accepted: 02/15/2016] [Indexed: 12/20/2022]
Abstract
Acute myeloid leukemia (AML) remains a challenge to both patients and clinicians. Despite improvements in our understanding of the disease, treatment has changed minimally and outcomes remain poor for the majority of patients. Within the last decade, there have been an increasing number of potential targets and pathways identified for development in AML. The classes of agents described in this review include but are not limited to epigenetic modifiers such as IDH inhibitors, BET inhibitors, and HDAC inhibitors as well as cell cycle and signaling inhibitors such as Aurora kinase inhibitors and CDK inhibitors. While the developments are encouraging, it is unlikely that targeting a single pathway will result in long-term disease control. Accordingly, we will also highlight potential rational partners for the novel agents described herein.
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Affiliation(s)
| | - Steven Grant
- Virginia Commonwealth University, Richmond, VA, USA
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11
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De Miguel D, Gallego-Lleyda A, Ayuso JM, Erviti-Ardanaz S, Pazo-Cid R, del Agua C, Fernández LJ, Ochoa I, Anel A, Martinez-Lostao L. TRAIL-coated lipid-nanoparticles overcome resistance to soluble recombinant TRAIL in non-small cell lung cancer cells. NANOTECHNOLOGY 2016; 27:185101. [PMID: 27001952 DOI: 10.1088/0957-4484/27/18/185101] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
PURPOSE Non-small cell lung cancer (NSCLC) is one the types of cancer with higher prevalence and mortality. Apo2-Ligand/TRAIL is a TNF family member able to induce apoptosis in tumor cells but not in normal cells. It has been tested in clinical trials against different types of human cancer including NSCLC. However, results of clinical trials have shown a limited efficacy of TRAIL-based therapies. Recently we have demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) greatly improved TRAIL cytotoxic ability being capable of killing chemoresistant hematological cancer cells. In the present work we have extended the study to NSCLC. METHODS/PATIENTS LUV-TRAIL-induced cytotoxicity was assessed on different NSCLC cell lines with different sensitivity to soluble TRAIL and on primary human tumor cells from three patients suffering from NSCLC cancer. We also tested LUV-TRAIL-cytotoxic ability in combination with several anti-tumor agents. RESULTS LUV-TRAIL exhibited a greater cytotoxic effect compared to soluble TRAIL both in A549 cells and primary human NSCLC cells. LUV-TRAIL-induced cell death was dependent on caspase-8 and caspase-3 activation. Moreover, combination of LUV-TRAIL with other anti-tumor agents such as flavopiridol, and SNS-032 clearly enhanced LUV-TRAIL-induced cytotoxicity against NSCLC cancer cells. CONCLUSION The novel formulation of TRAIL based on displaying it on the surface of lipid nanoparticles greatly increases its anti-tumor activity and has clinical potential in cancer treatment.
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Affiliation(s)
- Diego De Miguel
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, Spain
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12
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Tanaka N, Patel AA, Wang J, Frederick MJ, Kalu NN, Zhao M, Fitzgerald AL, Xie TX, Silver NL, Caulin C, Zhou G, Skinner HD, Johnson FM, Myers JN, Osman AA. Wee-1 Kinase Inhibition Sensitizes High-Risk HPV+ HNSCC to Apoptosis Accompanied by Downregulation of MCl-1 and XIAP Antiapoptotic Proteins. Clin Cancer Res 2015; 21:4831-44. [PMID: 26124202 DOI: 10.1158/1078-0432.ccr-15-0279] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 06/12/2015] [Indexed: 12/21/2022]
Abstract
PURPOSE Although the majority of patients with HPV(+) oropharyngeal cancers have a favorable prognosis, there are some patients with tumors that are resistant to aggressive chemoradiotherapy with unusual patterns of locoregional and systemic recurrences. Therefore, more effective therapies are needed. In this study, we investigated the chemosensitizing efficacy of the selective Wee-1 kinase inhibitor, AZD-1775, in HPV(+) head and neck squamous cell carcinoma (HNSCC). EXPERIMENTAL DESIGN Clonogenic survival assays and an orthotopic mouse model of HPV(+) oral cancer were used to examine the in vitro and in vivo sensitivity of HPV(+) HNSCC cell lines to AZD-1775 in combination with cisplatin, respectively. Cell-cycle analysis, DNA damage (γH2AX), homologous recombination (HR), and apoptosis were examined to dissect molecular mechanisms. RESULTS We found that AZD-1775 displays single-agent activity and enhances the response of HPV(+) HNSCC cells to cisplatin both in vitro and in vivo. The sensitivity of the HPV(+) HNSCC cells to AZD-1775 alone or in combination with cisplatin was associated with G2 checkpoint abrogation, persistent DNA damage, and apoptosis induction. This finding of AZD-1775 increasing the sensitivity of HPV(+) HNSCC cells to cisplatin through apoptosis was not seen previously in the HPV(-) HNSCC cancer cells and is accompanied by a decreased expression of the antiapoptotic proteins, MCl-1and XIAP, which appear to be cleaved following AZD-1775 treatment. CONCLUSIONS AZD-1775 selectively sensitizes HPV(+) HNSCC cells and orthotopic oral xenografts to cisplatin through apoptosis and support the clinical investigation of AZD-1775 in combination with cisplatin particularly in patients with advanced and recurrent metastatic HPV(+) HNSCC tumors.
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Affiliation(s)
- Noriaki Tanaka
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Ameeta A Patel
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jiping Wang
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Mitchell J Frederick
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Nene N Kalu
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Mei Zhao
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Alison L Fitzgerald
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Tong-xin Xie
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Natalie L Silver
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Carlos Caulin
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Ge Zhou
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Heath D Skinner
- Department of Thoracic Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Faye M Johnson
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jeffrey N Myers
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.
| | - Abdullah A Osman
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.
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Abstract
INTRODUCTION Patients with relapsed or refractory lymphoma remain a population with unmet medical needs. Histone deacetylase inhibitors (HDACIs) represent a novel class of anticancer drugs currently in development in several malignancies. Inhibition of HDACs leads to acetylation of histone and non-histone proteins, which in turn results in epigenetic modification of gene expression that leads to a plethora of effects, such as cell cycle arrest, apoptosis and inhibition of angiogenesis. Romidepsin is a novel HDACI that has demonstrated preclinical and clinical activity. AREAS COVERED This review discusses the different HDACs and epigenetic regulation with a particular focus on the preclinical and clinical development of romidepsin in lymphoma. The review of romidepsin includes: the mechanism of action, its synergistic interaction with novel agents, pivotal clinical trials that lead to its US FDA approval in cutaneous T-cell lymphoma and peripheral T-cell lymphoma as well as active combinations currently in clinical trials. EXPERT OPINION Romidepsin is a potent HDACI with clinical activity in T-cell lymphoma where novel agents and combinations are desperately needed. A deeper understanding of the molecular characteristics of this class of agents will allow the design of more potent drugs with improved toxicity profiles and future rational combinations that will expand the indication and benefit from these novel agents.
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Affiliation(s)
- Victor Y Yazbeck
- Virginia Commonwealth University, Massey Cancer Center , Richmond, VA , USA
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14
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Bose P, Grant S. Rational Combinations of Targeted Agents in AML. J Clin Med 2015; 4:634-664. [PMID: 26113989 PMCID: PMC4470160 DOI: 10.3390/jcm4040634] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 01/06/2015] [Indexed: 12/20/2022] Open
Abstract
Despite modest improvements in survival over the last several decades, the treatment of AML continues to present a formidable challenge. Most patients are elderly, and these individuals, as well as those with secondary, therapy-related, or relapsed/refractory AML, are particularly difficult to treat, owing to both aggressive disease biology and the high toxicity of current chemotherapeutic regimens. It has become increasingly apparent in recent years that coordinated interruption of cooperative survival signaling pathways in malignant cells is necessary for optimal therapeutic results. The modest efficacy of monotherapy with both cytotoxic and targeted agents in AML testifies to this. As the complex biology of AML continues to be elucidated, many “synthetic lethal” strategies involving rational combinations of targeted agents have been developed. Unfortunately, relatively few of these have been tested clinically, although there is growing interest in this area. In this article, the preclinical and, where available, clinical data on some of the most promising rational combinations of targeted agents in AML are summarized. While new molecules should continue to be combined with conventional genotoxic drugs of proven efficacy, there is perhaps a need to rethink traditional philosophies of clinical trial development and regulatory approval with a focus on mechanism-based, synergistic strategies.
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Affiliation(s)
- Prithviraj Bose
- Department of Internal Medicine, Virginia Commonwealth University and VCU Massey Cancer Center Center, 1201 E Marshall St, MMEC 11-213, P.O. Box 980070, Richmond, VA 23298, USA; E-Mail:
| | - Steven Grant
- Departments of Internal Medicine, Microbiology and Immunology, Biochemistry and Molecular Biology, Human and Molecular Genetics and the Institute for Molecular Medicine, Virginia Commonwealth University and VCU Massey Cancer Center, 401 College St, P.O. Box 980035, Richmond, VA 23298, USA
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-804-828-5211; Fax: +1-804-628-5920
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15
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Ema Y, Igase M, Takeda Y, Yanase T, Umeki S, Hiraoka H, Okuda M, Mizuno T. Investigation of the cytotoxic effect of flavopiridol in canine lymphoma cell lines. Vet Comp Oncol 2015; 14 Suppl 1:95-106. [DOI: 10.1111/vco.12130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 10/30/2014] [Accepted: 11/04/2014] [Indexed: 11/27/2022]
Affiliation(s)
- Y. Ema
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
| | - M. Igase
- Laboratory of Molecular Diagnostics and Therapeutics, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
| | - Y. Takeda
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
| | - T. Yanase
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
| | - S. Umeki
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
| | - H. Hiraoka
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
| | - M. Okuda
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
- Biomedical Science Center for Translational Research; The United Graduate School of Veterinary Science, Yamaguchi University; Yamaguchi Japan
| | - T. Mizuno
- Laboratory of Veterinary Internal Medicine, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
- Laboratory of Molecular Diagnostics and Therapeutics, Joint Faculty of Veterinary Medicine; Yamaguchi University; Yamaguchi Japan
- Biomedical Science Center for Translational Research; The United Graduate School of Veterinary Science, Yamaguchi University; Yamaguchi Japan
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16
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Bose P, Dai Y, Grant S. Histone deacetylase inhibitor (HDACI) mechanisms of action: emerging insights. Pharmacol Ther 2014; 143:323-36. [PMID: 24769080 PMCID: PMC4117710 DOI: 10.1016/j.pharmthera.2014.04.004] [Citation(s) in RCA: 204] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 04/10/2014] [Indexed: 02/05/2023]
Abstract
Initially regarded as "epigenetic modifiers" acting predominantly through chromatin remodeling via histone acetylation, HDACIs, alternatively referred to as lysine deacetylase or simply deacetylase inhibitors, have since been recognized to exert multiple cytotoxic actions in cancer cells, often through acetylation of non-histone proteins. Some well-recognized mechanisms of HDACI lethality include, in addition to relaxation of DNA and de-repression of gene transcription, interference with chaperone protein function, free radical generation, induction of DNA damage, up-regulation of endogenous inhibitors of cell cycle progression, e.g., p21, and promotion of apoptosis. Intriguingly, this class of agents is relatively selective for transformed cells, at least in pre-clinical studies. In recent years, additional mechanisms of action of these agents have been uncovered. For example, HDACIs interfere with multiple DNA repair processes, as well as disrupt cell cycle checkpoints, critical to the maintenance of genomic integrity in the face of diverse genotoxic insults. Despite their pre-clinical potential, the clinical use of HDACIs remains restricted to certain subsets of T-cell lymphoma. Currently, it appears likely that the ultimate role of these agents will lie in rational combinations, only a few of which have been pursued in the clinic to date. This review focuses on relatively recently identified mechanisms of action of HDACIs, with particular emphasis on those that relate to the DNA damage response (DDR), and discusses synergistic strategies combining HDACIs with several novel targeted agents that disrupt the DDR or antagonize anti-apoptotic proteins that could have implications for the future use of HDACIs in patients with cancer.
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Affiliation(s)
- Prithviraj Bose
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA; Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Yun Dai
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA; Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Steven Grant
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA; Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA; Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA; Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, USA; Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA; Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, VA, USA.
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DHA2, a synthesized derivative of bisbibenzyl, exerts antitumor activity against ovarian cancer through inhibition of XIAP and Akt/mTOR pathway. Food Chem Toxicol 2014; 69:163-74. [DOI: 10.1016/j.fct.2014.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 04/02/2014] [Accepted: 04/05/2014] [Indexed: 11/24/2022]
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18
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Bose P, Grant S. Orphan drug designation for pracinostat, volasertib and alvocidib in AML. Leuk Res 2014; 38:862-5. [PMID: 24996975 DOI: 10.1016/j.leukres.2014.06.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 06/08/2014] [Indexed: 12/20/2022]
Affiliation(s)
- Prithviraj Bose
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA; Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Steven Grant
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA; Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA; Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA; Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, USA; Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA; Institute for Molecular Medicine, Virginia Commonwealth University, Richmond, VA, USA.
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20
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Pierceall WE, Lena RJ, Medeiros BC, Blake N, Doykan C, Elashoff M, Cardone MH, Walter RB. Mcl-1 dependence predicts response to vorinostat and gemtuzumab ozogamicin in acute myeloid leukemia. Leuk Res 2014; 38:564-8. [PMID: 24636337 DOI: 10.1016/j.leukres.2014.02.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 02/14/2014] [Accepted: 02/18/2014] [Indexed: 02/06/2023]
Abstract
Older adults with acute myeloid leukemia (AML) are commonly considered for investigational therapies, which often only benefit subsets of patients. In this study, we assessed whether BH3 profiling of apoptotic functionality could predict outcomes following treatment with vorinostat (histone deacetylase inhibitor) and gemtuzumab ozogamicin (GO; CD33-targeted immunoconjugate). Flow cytometry of BH3 peptide priming with Noxa (anti-apoptotic protein Mcl-1 modulator) correlated with remission induction (p=.026; AUC=0.83 [CI: 0.65-1.00; p=.00042]: AUC=0.88 [CI:0.75-1.00] with age adjustment) and overall survival (p=.027 logistic regression; AUC=0.87 [0.64-1.00; p=.0017]). This Mcl-1-dependence suggests a pivotal role of Bcl-2 family protein-mediated apoptosis to vorinostat/GO in AML patients.
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Affiliation(s)
| | - Ryan J Lena
- Eutropics Pharmaceuticals, Inc., Cambridge, MA, United States
| | | | - Noel Blake
- Eutropics Pharmaceuticals, Inc., Cambridge, MA, United States
| | - Camille Doykan
- Eutropics Pharmaceuticals, Inc., Cambridge, MA, United States
| | | | | | - Roland B Walter
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States; Department of Medicine, Division of Hematology, University of Washington, Seattle, WA, United States; Department of Epidemiology, University of Washington, Seattle, WA, United States.
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21
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Liu H, Yang J, Yuan Y, Xia Z, Chen M, Xie L, Ma X, Wang J, Ouyang S, Wu Q, Yu F, Zhou X, Yang Y, Cao Y, Hu J, Yin B. Regulation of Mcl-1 by constitutive activation of NF-κB contributes to cell viability in human esophageal squamous cell carcinoma cells. BMC Cancer 2014; 14:98. [PMID: 24529193 PMCID: PMC3930545 DOI: 10.1186/1471-2407-14-98] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 02/11/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies with a 5-year survival rate less than 15%. Understanding of the molecular mechanisms involved in the pathogenesis of ESCC becomes critical to develop more effective treatments. METHODS Mcl-1 expression was measured by reverse transcription (RT)-PCR and Western blotting. Human Mcl-1 promoter activity was evaluated by reporter gene assay. The interactions between DNA and transcription factors were confirmed by electrophoretic mobility shift assay (EMSA) in vitro and by chromatin immunoprecipitation (ChIP) assay in cells. RESULTS Four human ESCC cell lines, TE-1, Eca109, KYSE150 and KYSE510, are revealed increased levels of Mcl-1 mRNA and protein compare with HaCaT, an immortal non-tumorigenic cell line. Results of reporter gene assays demonstrate that human Mcl-1 promoter activity is decreased by mutation of kappaB binding site, specific NF-kappaB inhibitor Bay11-7082 or dominant inhibitory molecule DNMIkappaBalpha in TE-1 and KYSE150 cell lines. Mcl-1 protein level is also attenuated by Bay11-7082 treatment or co-transfection of DNMIkappaBalpha in TE-1 and KYSE150 cells. EMSA results indicate that NF-kappaB subunits p50 and p65 bind to human Mcl-1-kappaB probe in vitro. ChIP assay further confirm p50 and p65 directly bind to human Mcl-1 promoter in intact cells, by which regulates Mcl-1 expression and contributes to the viability of TE-1 cells. CONCLUSIONS Our data provided evidence that one of the mechanisms of Mcl-1 expression in human ESCC is regulated by the activation of NF-kappaB signaling. The newly identified mechanism might provide a scientific basis for developing effective approaches to treatment human ESCC.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Jianguo Hu
- Department of Cardiothoracic Surgery, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, Hunan 410011, China.
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22
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Implication of transcriptional repression in compound C-induced apoptosis in cancer cells. Cell Death Dis 2013; 4:e883. [PMID: 24157877 PMCID: PMC3920957 DOI: 10.1038/cddis.2013.419] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 09/14/2013] [Accepted: 09/17/2013] [Indexed: 12/25/2022]
Abstract
Compound C, a well-known inhibitor of AMP-activated protein kinase (AMPK), has been reported to induce apoptosis in some types of cells. However, the underlying mechanisms remain largely unclear. Using a DNA microarray analysis, we found that the expression of many genes was downregulated upon treatment with compound C. Importantly, compound C caused transcriptional repression with the induction of p53, a well-known marker of transcriptional stress response, in several cancer cell lines. Compound C did not induce the phosphorylation of p53 but dramatically increased the protein level of p53 similar to some other transcriptional inhibitors, including 5,6-dichloro-1-β-D-ribobenzimidazole (DRB). Consistent with previous reports, we found that compound C initiated apoptotic death of cancer cells in an AMPK-independent manner. Similar to DRB and actinomycin D (ActD), two classic transcription inhibitors, compound C not only resulted in the loss of Bcl-2 and Bcl-xl protein but also induced the phosphorylation of eukaryotic initiation factor-alpha (eIF2α) on Ser51. Hence, the phosphorylation of eIF2α might be a novel marker of transcriptional inhibition. It is noteworthy that compound C-mediated apoptosis of cancer cells is correlated with decreased expression of Bcl-2 and Bcl-xl and the phosphorylation of eIF2α on Ser51. Remarkably, compound C exhibits potent anticancer activities in vivo. Taken together, our data suggest that compound C may be an attractive candidate for anticancer drug development.
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23
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Pallis M, Burrows F, Whittall A, Boddy N, Seedhouse C, Russell N. Efficacy of RNA polymerase II inhibitors in targeting dormant leukaemia cells. BMC Pharmacol Toxicol 2013; 14:32. [PMID: 23767415 PMCID: PMC3685571 DOI: 10.1186/2050-6511-14-32] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 06/05/2013] [Indexed: 11/16/2022] Open
Abstract
Background Dormant cells are characterised by low RNA synthesis. In contrast, cancer cells can be addicted to high RNA synthesis, including synthesis of survival molecules. We hypothesised that dormant cancer cells, already low in RNA, might be sensitive to apoptosis induced by RNA Polymerase II (RP2) inhibitors that further reduce RNA synthesis. Methods We cultured leukaemia cells continuously in vitro in the presence of an mTOR inhibitor to model dormancy. Apoptosis, damage, RNA content and reducing capacity were evaluated. We treated dormancy-enriched cells for 48 hours with the nucleoside analogues ara-C, 5-azacytidine and clofarabine, the topoisomerase targeting agents daunorubicin, etoposide and irinotecan and three multikinase inhibitors with activity against RP2 - flavopiridol, roscovitine and TG02, and we measured growth inhibition and apoptosis. We describe use of the parameter 2 × IC50 to measure residual cell targeting. RNA synthesis was measured with 5-ethynyl uridine. Drug-induced apoptosis was measured flow cytometrically in primary cells from patients with acute myeloid leukaemia using a CD34/CD71/annexinV gating strategy to identify dormant apoptotic cells. Results Culture of the KG1a cell line continuously in the presence of an mTOR inhibitor induced features of dormancy including low RNA content, low metabolism and low basal ROS formation in the absence of a DNA damage response or apoptosis. All agents were more effective against the unmanipulated than the dormancy-enriched cells, emphasising the chemoresistant nature of dormant cells. However, the percentage of cell reduction by RP2 inhibitors at 2 × IC50 was significantly greater than that of other agents. RP2 inhibitors strongly inhibited RNA synthesis compared with other drugs. We also showed that RP2 inhibitors induce apoptosis in proliferating and dormancy-enriched KG1a cells and in the CD71neg CD34pos subset of primary acute myeloid leukaemia cells. Conclusion We suggest that RP2 inhibitors may be a useful class of agent for targeting dormant leukaemia cells.
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24
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Bose P, Simmons GL, Grant S. Cyclin-dependent kinase inhibitor therapy for hematologic malignancies. Expert Opin Investig Drugs 2013; 22:723-38. [PMID: 23647051 PMCID: PMC4039040 DOI: 10.1517/13543784.2013.789859] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
INTRODUCTION Cyclin-dependent kinases (CDKs) regulate cell cycle progression. Certain CDKs (e.g., CDK7, CDK9) also control cellular transcription. Consequently, CDKs represent attractive targets for anticancer drug development, as their aberrant expression is common in diverse malignancies, and CDK inhibition can trigger apoptosis. CDK inhibition may be particularly successful in hematologic malignancies, which are more sensitive to inhibition of cell cycling and apoptosis induction. AREAS COVERED A number of CDK inhibitors, ranging from pan-CDK inhibitors such as flavopiridol (alvocidib) to highly selective inhibitors of specific CDKs (e.g., CDK4/6), such as PD0332991, that are currently in various phases of development, are profiled in this review. Flavopiridol induces cell cycle arrest, and globally represses transcription via CDK9 inhibition. The latter may represent its major mechanism of action via down-regulation of multiple short-lived proteins. In early phase trials, flavopiridol has shown encouraging efficacy across a wide spectrum of hematologic malignancies. Early results with dinaciclib and PD0332991 also appear promising. EXPERT OPINION In general, the antitumor efficacy of CDK inhibitor monotherapy is modest, and rational combinations are being explored, including those involving other targeted agents. While selective CDK4/6 inhibition might be effective against certain malignancies, broad-spectrum CDK inhibition will likely be required for most cancers.
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Affiliation(s)
- Prithviraj Bose
- Virginia Commonwealth University, Internal Medicine, 1101 E Marshall
St, Sanger Hall, Richmond, VA 23298, USA
| | - Gary L Simmons
- Virginia Commonwealth University, Internal Medicine, 1101 E Marshall
St, Sanger Hall, Richmond, VA 23298, USA
| | - Steven Grant
- Virginia Commonwealth University, Internal Medicine, 1101 E Marshall
St, Sanger Hall, Richmond, VA 23298, USA
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Abstract
Histone deacetylase inhibitors (HDACIs) are epigenetically acting agents that modify chromatin structure and by extension, gene expression. However, they may influence the behavior and survival of transformed cells by diverse mechanisms, including promoting expression of death- or differentiation-inducing genes while downregulating the expression of prosurvival genes; acting directly to increase oxidative injury and DNA damage; acetylating and disrupting the function of multiple proteins, including DNA repair and chaperone proteins; and interfering with the function of corepressor complexes. Notably, HDACIs have been shown in preclinical studies to target transformed cells selectively, and these agents have been approved in the treatment of certain hematologic malignancies, for example, cutaneous T-cell lymphoma and peripheral T-cell lymphoma. However, attempts to extend the spectrum of HDACI activity to other malignancies, for example, solid tumors, have been challenging. This has led to the perception that HDACIs may have limited activity as single agents. Because of the pleiotropic actions of HDACIs, combinations with other antineoplastic drugs, particularly other targeted agents, represent a particularly promising avenue of investigation. It is likely that emerging insights into mechanism(s) of HDACI activity will allow optimization of this approach, and hopefully, will expand HDACI approvals to additional malignancies in the future.
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Affiliation(s)
- Steven Grant
- Division of Hematology/Oncology, Virginia Commonwealth University Health Sciences Center, Richmond, Virginia, USA.
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26
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Holkova B, Supko JG, Ames MM, Reid JM, Shapiro GI, Perkins EB, Ramakrishnan V, Tombes MB, Honeycutt C, McGovern RM, Kmieciak M, Shrader E, Wellons MD, Sankala H, Doyle A, Wright J, Roberts JD, Grant S. A phase I trial of vorinostat and alvocidib in patients with relapsed, refractory, or poor prognosis acute leukemia, or refractory anemia with excess blasts-2. Clin Cancer Res 2013; 19:1873-83. [PMID: 23515411 DOI: 10.1158/1078-0432.ccr-12-2926] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE This phase I study was conducted to identify the maximum-tolerated dose (MTD) of alvocidib when combined with vorinostat in patients with relapsed, refractory, or poor prognosis acute leukemia, or refractory anemia with excess blasts-2. Secondary objectives included investigating the pharmacokinetic and pharmacodynamic effects of the combination. EXPERIMENTAL DESIGN Patients received vorinostat (200 mg orally, three times a day, for 14 days) on a 21-day cycle, combined with 2 different alvocidib administration schedules: a 1-hour intravenous infusion, daily × 5; or a 30-minute loading infusion followed by a 4-hour maintenance infusion, weekly × 2. The alvocidib dose was escalated using a standard 3+3 design. RESULTS Twenty-eight patients were enrolled and treated. The alvocidib MTD was 20 mg/m(2) (30-minute loading infusion) followed by 20 mg/m(2) (4-hour maintenance infusion) on days one and eight, in combination with vorinostat. The most frequently encountered toxicities were cytopenias, fatigue, hyperglycemia, hypokalemia, hypophosphatemia, and QT prolongation. Dose-limiting toxicities (DLT) were cardiac arrhythmia-atrial fibrillation and QT prolongation. No objective responses were achieved although 13 of 26 evaluable patients exhibited stable disease. Alvocidib seemed to alter vorinostat pharmacokinetics, whereas alvocidib pharmacokinetics were unaffected by vorinostat. Ex vivo exposure of leukemia cells to plasma obtained from patients after alvocidib treatment blocked vorinostat-mediated p21(CIP1) induction and downregulated Mcl-1 and p-RNA Pol II for some specimens, although parallel in vivo bone marrow responses were infrequent. CONCLUSIONS Alvocidib combined with vorinostat is well tolerated. Although disease stabilization occurred in some heavily pretreated patients, objective responses were not obtained with these schedules.
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Affiliation(s)
- Beata Holkova
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA 23298, USA.
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Transcription and translation are primary targets of Pim kinase inhibitor SGI-1776 in mantle cell lymphoma. Blood 2012; 120:3491-500. [PMID: 22955922 DOI: 10.1182/blood-2012-02-412643] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Proviral integration site for Moloney murine leukemia virus (Pim) kinases are serine/threonine/tyrosine kinases and oncoproteins that promote tumor progression. Three isoforms of Pim kinases have been identified and are known to phosphorylate numerous substrates, with regulatory functions in transcription, translation, cell cycle, and survival pathways. These kinases are involved in production, proliferation, and survival of normal B cells and are overexpressed in B-cell malignancies such as mantle cell lymphoma (MCL). SGI-1776 is a small molecule and Pim kinase inhibitor with selectivity for Pim-1. We hypothesize that Pim kinase function can be inhibited by SGI-1776 in MCL and that inhibition of phosphorylation of downstream substrates will disrupt transcriptional, translational, and cell cycle processes and promote cell death. SGI-1776 treatment in 4 MCL cell lines resulted in apoptosis induction. Phosphorylation of transcription (c-Myc) and translation targets (4E-BP1), tested in Jeko-1 and Mino, was declined. Consistent with these data, Mcl-1 and cyclin D1 protein levels were decreased. Importantly, similar to cell line data, MCL primary cells but not normal cells showed similar inhibition of substrate phosphorylation and cytotoxicity from SGI-1776 treatment. Genetic knockdown of Pim-1/Pim-2 affected similar proteins in MCL cell lines. Collectively these data demonstrate Pim kinases as therapeutic targets in MCL.
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Pallis M, Abdul-Aziz A, Burrows F, Seedhouse C, Grundy M, Russell N. The multi-kinase inhibitor TG02 overcomes signalling activation by survival factors to deplete MCL1 and XIAP and induce cell death in primary acute myeloid leukaemia cells. Br J Haematol 2012; 159:191-203. [PMID: 22934750 DOI: 10.1111/bjh.12018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 07/16/2012] [Indexed: 01/10/2023]
Abstract
The novel multi-kinase inhibitor TG02 has selectivity against cell cycle and transcriptional cyclin dependent kinases (CDKs) as well as fms-like tyrosine kinase receptor-3 (FLT3). Inhibition of transcriptional CDKs preferentially depletes short-lived proteins such as MCL1. We evaluated the in vitro toxicity of TG02 to primary acute myeloid leukaemia (AML) cells in the presence of survival signalling pathway activation by cytokines and fibronectin. One hundred nanomolar TG02 induced a median decrease of 40% in bulk cell survival and 43% in the CD34(+) CD38(-) CD123(+) subset. A 90% inhibitory concentration of 500 nmol/l indicated that TG02 toxicity is not halted by protective cell cycle arrest. Samples with FLT3 internal tandem duplication were not preferentially targeted. By flow cytometry, TG02 treatment caused loss of RNA Polymerase II serine 2 phosphorylation in patient samples, which correlated strongly with BAX activation (R(2) =0·89), suggesting these as potential biomarkers for clinical studies. MCL1 and XIAP expression also decreased. Repeated brief exposure to TG02 in MOLM-13 cells did not result in compensatory up-regulation of survival protein expression. In conclusion, TG02 is potently cytotoxic towards CD34(+) CD38(-) CD123(+) and bulk AML cells, despite protective signalling pathway activation. This antitumour activity is most likely mediated by dephosphorylation of RNA Polymerase II leading to depletion of survival molecules such as MCL1 and XIAP, with subsequent BAX activation and apoptosis.
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Affiliation(s)
- Monica Pallis
- Academic Haematology, Nottingham University Hospitals City Campus, Clinical Sciences Building, Nottingham, UK.
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Cyclin-dependent kinase 9 activity regulates neutrophil spontaneous apoptosis. PLoS One 2012; 7:e30128. [PMID: 22276149 PMCID: PMC3261871 DOI: 10.1371/journal.pone.0030128] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 12/14/2011] [Indexed: 01/13/2023] Open
Abstract
Neutrophils are the most abundant leukocyte and play a central role in the immune defense against rapidly dividing bacteria. However, they are also the shortest lived cell in the blood with a lifespan in the circulation of 5.4 days. The mechanisms underlying their short lifespan and spontaneous entry into apoptosis are poorly understood. Recently, the broad range cyclin-dependent kinase (CDK) inhibitor R-roscovitine was shown to increase neutrophil apoptosis, implicating CDKs in the regulation of neutrophil lifespan. To determine which CDKs were involved in regulating neutrophil lifespan we first examined CDK expression in human neutrophils and found that only three CDKs: CDK5, CDK7 and CDK9 were expressed in these cells. The use of CDK inhibitors with differing selectivity towards the various CDKs suggested that CDK9 activity regulates neutrophil lifespan. Furthermore CDK9 activity and the expression of its activating partner cyclin T1 both declined as neutrophils aged and entered apoptosis spontaneously. CDK9 is a component of the P-TEFb complex involved in transcriptional regulation and its inhibition will preferentially affect proteins with short half-lives. Treatment of neutrophils with flavopiridol, a potent CDK9 inhibitor, increased apoptosis and caused a rapid decline in the level of the anti-apoptotic protein Mcl-1, whilst Bcl2A was unaffected. We propose that CDK9 activity is a key regulator of neutrophil lifespan, preventing apoptosis by maintaining levels of short lived anti-apoptotic proteins such as Mcl-1. Furthermore, as inappropriate inhibition of neutrophil apoptosis contributes to chronic inflammatory diseases such as Rheumatoid Arthritis, CDK9 represents a novel therapeutic target in such diseases.
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Transcription inhibition as a therapeutic target for cancer. Cancers (Basel) 2011; 3:4170-90. [PMID: 24213132 PMCID: PMC3763417 DOI: 10.3390/cancers3044170] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 11/14/2011] [Accepted: 11/16/2011] [Indexed: 01/10/2023] Open
Abstract
During tumorigenesis the transformed cells lose their normal growth control mechanisms and become dependent on oncogenes' products and pathways for survival. Treatments tailored to block the expression or function of transforming genes have shown efficacy in eliminating neoplastic cells. The mRNAs of many oncogenes, as well as regulators of other key processes such as cell proliferation, angiogenesis, and apoptosis, typically have shorter half-lives. Agents that impede mRNA synthesis are expected to selectively hinder the expression of these genes and, therefore, be detrimental to neoplastic cells that are physiologically dependent on them. In addition to exploiting the tumor cells' dependency on short-lived transcripts, RNA-directed agents also take advantage of the differential sensitivity between transformed and non-transformed cells, as the cytotoxic effects of inhibiting RNA synthesis have not been seen in non-transformed cells. The abrogation of the formation of oncotranscripts provides a new concept in cancer therapeutics and numerous agents have been developed which are able to target transcription. The focus of this review is to give an overview of transcription and the different inhibitory strategies that target various aspects of the transcriptional process.
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Merhi F, Tang R, Piedfer M, Mathieu J, Bombarda I, Zaher M, Kolb JP, Billard C, Bauvois B. Hyperforin inhibits Akt1 kinase activity and promotes caspase-mediated apoptosis involving Bad and Noxa activation in human myeloid tumor cells. PLoS One 2011; 6:e25963. [PMID: 21998731 PMCID: PMC3188562 DOI: 10.1371/journal.pone.0025963] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 09/14/2011] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The natural phloroglucinol hyperforin HF displays anti-inflammatory and anti-tumoral properties of potential pharmacological interest. Acute myeloid leukemia (AML) cells abnormally proliferate and escape apoptosis. Herein, the effects and mechanisms of purified HF on AML cell dysfunction were investigated in AML cell lines defining distinct AML subfamilies and primary AML cells cultured ex vivo. METHODOLOGY AND RESULTS HF inhibited in a time- and concentration-dependent manner the growth of AML cell lines (U937, OCI-AML3, NB4, HL-60) by inducing apoptosis as evidenced by accumulation of sub-G1 population, phosphatidylserine externalization and DNA fragmentation. HF also induced apoptosis in primary AML blasts, whereas normal blood cells were not affected. The apoptotic process in U937 cells was accompanied by downregulation of anti-apoptotic Bcl-2, upregulation of pro-apoptotic Noxa, mitochondrial membrane depolarization, activation of procaspases and cleavage of the caspase substrate PARP-1. The general caspase inhibitor Z-VAD-fmk and the caspase-9- and -3-specific inhibitors, but not caspase-8 inhibitor, significantly attenuated apoptosis. HF-mediated apoptosis was associated with dephosphorylation of active Akt1 (at Ser(473)) and Akt1 substrate Bad (at Ser(136)) which activates Bad pro-apoptotic function. HF supppressed the kinase activity of Akt1, and combined treatment with the allosteric Akt1 inhibitor Akt-I-VIII significantly enhanced apoptosis of U937 cells. SIGNIFICANCE Our data provide new evidence that HF's pro-apoptotic effect in AML cells involved inhibition of Akt1 signaling, mitochondria and Bcl-2 members dysfunctions, and activation of procaspases -9/-3. Combined interruption of mitochondrial and Akt1 pathways by HF may have implications for AML treatment.
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Affiliation(s)
- Faten Merhi
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
| | - Ruoping Tang
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
- AP-HP, Département d'Hématologie, Hôpital St Antoine, Paris, France
| | - Marion Piedfer
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
| | | | - Isabelle Bombarda
- ISM2-AD2M, UMR CNRS 6263, Université Paul Cézanne, Marseille, France
| | - Murhaf Zaher
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
| | - Jean-Pierre Kolb
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
| | - Christian Billard
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
| | - Brigitte Bauvois
- INSERM U872, Université Pierre et Marie Curie, Université Paris Descartes, Centre de Recherche des Cordeliers, Paris, France
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Quinn BA, Dash R, Azab B, Sarkar S, Das SK, Kumar S, Oyesanya RA, Dasgupta S, Dent P, Grant S, Rahmani M, Curiel DT, Dmitriev I, Hedvat M, Wei J, Wu B, Stebbins JL, Reed JC, Pellecchia M, Sarkar D, Fisher PB. Targeting Mcl-1 for the therapy of cancer. Expert Opin Investig Drugs 2011; 20:1397-411. [PMID: 21851287 DOI: 10.1517/13543784.2011.609167] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Human cancers are genetically and epigenetically heterogeneous and have the capacity to commandeer a variety of cellular processes to aid in their survival, growth and resistance to therapy. One strategy is to overexpress proteins that suppress apoptosis, such as the Bcl-2 family protein Mcl-1. The Mcl-1 protein plays a pivotal role in protecting cells from apoptosis and is overexpressed in a variety of human cancers. AREAS COVERED Targeting Mcl-1 for extinction in these cancers, using genetic and pharmacological approaches, represents a potentially effectual means of developing new efficacious cancer therapeutics. Here we review the multiple strategies that have been employed in targeting this fundamental protein, as well as the significant potential these targeting agents provide in not only suppressing cancer growth, but also in reversing resistance to conventional cancer treatments. EXPERT OPINION We discuss the potential issues that arise in targeting Mcl-1 and other Bcl-2 anti-apoptotic proteins, as well problems with acquired resistance. The application of combinatorial approaches that involve inhibiting Mcl-1 and manipulation of additional signaling pathways to enhance therapeutic outcomes is also highlighted. The ability to specifically inhibit key genetic/epigenetic elements and biochemical pathways that maintain the tumor state represent a viable approach for developing rationally based, effective cancer therapies.
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Affiliation(s)
- Bridget A Quinn
- Virginia Commonwealth University, School of Medicine, Department of Human and Molecular Genetics, Richmond, VA, USA.
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Bates DJP, Salerni BL, Lowrey CH, Eastman A. Vinblastine sensitizes leukemia cells to cyclin-dependent kinase inhibitors, inducing acute cell cycle phase-independent apoptosis. Cancer Biol Ther 2011; 12:314-25. [PMID: 21768777 DOI: 10.4161/cbt.12.4.16909] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The efficacy of many chemotherapeutic agents can be attenuated by expression of the anti-apoptotic proteins Bcl-2, Bcl-X(L) and Mcl-1. Flavopiridol and dinaciclib are cyclin-dependent kinase 7 and 9 inhibitors that transcriptionally inhibit expression of Mcl-1. We have investigated the ability of flavopiridol and dinaciclib to sensitize a panel of leukemia cell lines to vinblastine and paclitaxel. Both drugs acutely sensitized most of the leukemia lines to vinblastine, with 100% apoptosis in 4 h. Furthermore, dinaciclib sensitized freshly isolated chronic lymphocytic leukemia cells to vinblastine. This rapid induction of apoptosis was attributed to vinblastine-mediated activation of JNK because (a) flavopiridol and dinaciclib failed to induce apoptosis when combined with non-JNK activating concentrations of vinblastine; (b) JNK inhibitors suppressed JNK activity and prevented apoptosis; (c) flavopiridol did not potentiate apoptosis induced by paclitaxel which does not activate JNK in these cells; and (d) Jurkat cells failed to activate JNK in response to vinblastine and were not sensitive to combinations of vinblastine and flavopiridol or dinaciclib. The rapid induction of apoptosis by this combination in multiple cell systems but not in normal lymphocytes provides justification for performing a clinical trial to assess the efficacy in patients.
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Affiliation(s)
- Darcy J P Bates
- Department of Pharmacology and Toxicology, Dartmouth Medical School, Lebanon, NH, USA
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Polier G, Ding J, Konkimalla BV, Eick D, Ribeiro N, Köhler R, Giaisi M, Efferth T, Desaubry L, Krammer PH, Li-Weber M. Wogonin and related natural flavones are inhibitors of CDK9 that induce apoptosis in cancer cells by transcriptional suppression of Mcl-1. Cell Death Dis 2011; 2:e182. [PMID: 21776020 PMCID: PMC3199715 DOI: 10.1038/cddis.2011.66] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The wogonin-containing herb Scutellaria baicalensis has successfully been used for curing various diseases in traditional Chinese medicine. Wogonin has been shown to induce apoptosis in different cancer cells and to suppress growth of human cancer xenografts in vivo. However, its direct targets remain unknown. In this study, we demonstrate for the first time that wogonin and structurally related natural flavones, for example, apigenin, chrysin and luteolin, are inhibitors of cyclin-dependent kinase 9 (CDK9) and block phosphorylation of the carboxy-terminal domain of RNA polymerase II at Ser2. This effect leads to reduced RNA synthesis and subsequently rapid downregulation of the short-lived anti-apoptotic protein myeloid cell leukemia 1 (Mcl-1) resulting in apoptosis induction in cancer cells. We show that genetic inhibition of Mcl-1 or CDK9 expression by siRNA is sufficient to mimic flavone-induced apoptosis. Pull-down and in silico docking studies demonstrate that wogonin directly binds to CDK9, presumably to the ATP-binding pocket. In contrast, wogonin does not inhibit CDK2, CDK4 and CDK6 at doses that inhibit CDK9 activity. Furthermore, we show that wogonin preferentially inhibits CDK9 in malignant compared with normal lymphocytes. Thus, our study reveals a new mechanism of anti-cancer action of natural flavones and supports CDK9 as a therapeutic target in oncology.
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Affiliation(s)
- G Polier
- Tumor Immunology Program (D030), German Cancer Research Center (DKFZ), Heidelberg, Germany
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Abstract
Pim kinases are Ser/Thr kinases with multiple substrates that affect survival pathways. These proteins are overexpressed in acute myeloid leukemia (AML) blasts and we hypothesized that Pim kinase inhibition would affect AML cell survival. Imidazo[1,2-b]pyridazine compound, SGI-1776 inhibits Pim-1, Pim-2 and Pim-3, and was evaluated in AML-cell line, -xenograft model, and -primary blasts. Treatment of AML cells with SGI-1776 results in a concentration-dependent induction of apoptosis and we investigated its effect on Pim kinase functions. Phosphorylation of traditional Pim kinase targets, c-Myc(Ser62) and 4E-BP1 (Thr36/Thr47), were both decreased in actively cycling AML cell lines MV-4-11, MOLM-13 and OCI-AML-3. Levels of antiapoptotic proteins Bcl-2, Bcl-x(L), XIAP, and proapoptotic Bak and Bax were unchanged; however, a significant reduction in Mcl-1 was observed. This was correlated with inhibition of global RNA and protein synthesis and MCL-1 transcript decline after SGI-1776 treatment. These data suggest that SGI-1776 mechanism in AML involves Mcl-1 protein reduction. Consistent with cell line data, xenograft model studies with mice bearing MV-4-11 tumors showed efficacy with SGI-1776. Importantly, SGI-1776 was also cytotoxic in AML primary cells, irrespective of FLT3 mutation status and resulted in Mcl-1 protein decline. Pim kinase inhibition may be a new strategy for AML treatment.
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Xu J, Sampath D, Lang FF, Prabhu S, Rao G, Fuller GN, Liu Y, Puduvalli VK. Vorinostat modulates cell cycle regulatory proteins in glioma cells and human glioma slice cultures. J Neurooncol 2011; 105:241-51. [PMID: 21598070 DOI: 10.1007/s11060-011-0604-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 05/08/2011] [Indexed: 11/25/2022]
Abstract
Chromatin modification through histone deacetylase inhibition has shown evidence of activity against malignancies. The mechanism of action of such agents are pleiotropic and potentially tumor specific. In this study, we studied the mechanisms of vorinostat-induced cellular effects in gliomas. The effects of vorinostat on proliferation, induction of apoptosis and cell cycle effects were studied in vitro (D54, U87 and U373 glioma cell lines). To gain additional insights into its effects on human gliomas, vorinostat-induced changes were examined ex vivo using a novel organotypic human glioma slice model. Vorinostat treatment resulted in increased p21 levels in all glioma cells tested in a p53 independent manner. In addition, cyclin B1 levels were transcriptionally downregulated and resulted in reduced kinase activity of the cyclin B1/cdk1 complex causing a G2 arrest. These effects were associated with a dose- and time-dependent inhibition of cellular proliferation and anchorage-independent growth in association with hyperacetylation of core histones and induction of apoptosis. Of particular significance, we demonstrate histone hyperacetylation and increased p21 levels in freshly resected human glioma specimens maintained as organotypic slice cultures and exposed to vorinostat similar to cell lines suggesting that human glioma can be targeted by this agent. Our data suggest that the effects of vorinostat are associated with modulation of cell cycle related proteins and activation of a G2 checkpoint along with induction of apoptosis. These effects are mediated by both transcriptional and post-translational mechanisms which provide potential options that can be exploited to develop new therapeutic approaches against gliomas.
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Affiliation(s)
- Jihong Xu
- Department of Neuro-Oncology, The Brain Tumor Center, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Unit 431, Houston, TX 77030, USA
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PRL-3, a metastasis associated tyrosine phosphatase, is involved in FLT3-ITD signaling and implicated in anti-AML therapy. PLoS One 2011; 6:e19798. [PMID: 21589872 PMCID: PMC3093398 DOI: 10.1371/journal.pone.0019798] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Accepted: 04/13/2011] [Indexed: 02/06/2023] Open
Abstract
Combination with other small molecule drugs represents a promising strategy to improve therapeutic efficacy of FLT3 inhibitors in the clinic. We demonstrated that combining ABT-869, a FLT3 inhibitor, with SAHA, a HDAC inhibitor, led to synergistic killing of the AML cells with FLT3 mutations and suppression of colony formation. We identified a core gene signature that is uniquely induced by the combination treatment in 2 different leukemia cell lines. Among these, we showed that downregulation of PTP4A3 (PRL-3) played a role in this synergism. PRL-3 is downstream of FLT3 signaling and ectopic expression of PRL-3 conferred therapeutic resistance through upregulation of STAT (signal transducers and activators of transcription) pathway activity and anti-apoptotic Mcl-1 protein. PRL-3 interacts with HDAC4 and SAHA downregulates PRL-3 via a proteasome dependent pathway. In addition, PRL-3 protein was identified in 47% of AML cases, but was absent in myeloid cells in normal bone marrows. Our results suggest such combination therapies may significantly improve the therapeutic efficacy of FLT3 inhibitors. PRL-3 plays a potential pathological role in AML and it might be a useful therapeutic target in AML, and warrant clinical investigation.
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Huang JM, Sheard MA, Ji L, Sposto R, Keshelava N. Combination of vorinostat and flavopiridol is selectively cytotoxic to multidrug-resistant neuroblastoma cell lines with mutant TP53. Mol Cancer Ther 2011; 9:3289-301. [PMID: 21159612 DOI: 10.1158/1535-7163.mct-10-0562] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
As p53 loss of function (LOF) confers high-level drug resistance in neuroblastoma, p53-independent therapies might have superior activity in recurrent neuroblastoma. We tested the activity of vorinostat, a histone deacetylase inhibitor, and flavopiridol, a pan-Cdk inhibitor, in a panel of multidrug-resistant neuroblastoma cell lines that included lines with wild-type (wt) and transcriptionally active TP53 (n = 3), mutated (mt), and LOF TP53 (n = 4) or p14(ARF) deletion (n = 1). The combination of vorinostat and flavopiridol was synergistic and significantly more cytotoxic (P < 0.001) in cell lines with p53-LOF and in the clones stably transfected with dominant-negative p53 plasmids. Cell cycle analysis by flow cytometry showed prominent cell-cycle arrest in G(2)/M (37%) for a cell line with wt TP53 (SK-N-RA) at 16 to 20 hours, while cells with mt TP53 (CHLA-90) slipped into sub-G(1) at 6 to 24 hours (25%-40% specific cell death). The morphological hallmarks of mitotic cell death, including defective spindle formation and abnormal cytokinesis, were detected by confocal microscopy after the treatment with vorinostat + flavopiridol combination in CHLA-90. The combination caused reduction in the expression of G(2)/M proteins (cyclin B1, Mad2, MPM2) in 2 cell lines with mt TP53 but not in those with wt TP53. Plk1 expression was reduced in all treated lines. Small interfering RNA knockdown of Mad2 and cyclin B1 or Plk1 synergistically reduced the clonogenicity of CHLA-90 cells. The combination of HDAC inhibitor and flavopiridol may be a unique approach to treating neuroblastomas with p53 LOF, one that evokes induction of mitotic failure.
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Affiliation(s)
- Jen-Ming Huang
- Division of Hematology-Oncology, Childrens Hospital Los Angeles, Los Angeles, CA 90027, USA
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Wang L, Harshman SW, Liu S, Ren C, Xu H, Sallans L, Grever M, Byrd JC, Marcucci G, Freitas MA. Assaying pharmacodynamic endpoints with targeted therapy: flavopiridol and 17AAG induced dephosphorylation of histone H1.5 in acute myeloid leukemia. Proteomics 2011; 10:4281-92. [PMID: 21110323 DOI: 10.1002/pmic.201000080] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Histone H1 is commonly used to assay kinase activity in vitro. As many promising targeted therapies affect kinase activity of specific enzymes involved in cancer transformation, H1 phosphorylation can serve as potential pharmacodynamic marker for drug activity within the cell. In this study we utilized a phosphoproteomic workflow to characterize histone H1 phosphorylation changes associated with two targeted therapies in the Kasumi-1 acute myeloid leukemia cell line. The phosphoproteomic workflow was first validated with standard casein phosphoproteins and then applied to the direct analysis of histone H1 from Kasumi-1 nuclear lysates. Ten H1 phosphorylation sites were identified on the H1 variants, H1.2, H1.3, H1.4, H1.5 and H1.x. LC MS profiling of intact H1s demonstrated global dephosphorylation of H1.5 associated with therapy by the cyclin-dependent kinase inhibitor, flavopiridol and the Heat Shock Protein 90 inhibitor, 17-(Allylamino)-17-demethoxygeldanamycin. In contrast, independent treatments with a nucleotide analog, proteosome inhibitor and histone deacetylase inhibitor did not exhibit decreased H1.5 phosphorylation. The data presented herein demonstrate that potential of histones to assess the cellular response of reagents that have direct and indirect effects on kinase activity that alters histone phosphorylation. As such, this approach may be a highly informative marker for response to targeted therapies influencing histone phosphorylation.
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Affiliation(s)
- Liwen Wang
- Department of Chemistry, The Ohio State University, Columbus OH, USA
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Walsby E, Lazenby M, Pepper C, Burnett AK. The cyclin-dependent kinase inhibitor SNS-032 has single agent activity in AML cells and is highly synergistic with cytarabine. Leukemia 2011; 25:411-9. [PMID: 21212792 DOI: 10.1038/leu.2010.290] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
SNS-032 (BMS-387032) is a selective cyclin-dependent kinase (CDK) inhibitor. In this study, we evaluated its effects on primary acute myeloid leukemia (AML) samples (n=87). In vitro exposure to SNS-032 for 48 h resulted in a mean LD(50) of 139±203 nM; Cytarabine (Ara-C) was more than 35 times less potent in the same cohort. SNS-032-induced a dose-dependent increase in annexin V staining and caspase-3 activation. At the molecular level, SNS-032 induced a marked dephosphorylation of serine 2 and 5 of RNA polymerase (RNA Pol) II and inhibited the expression of CDK2 and CDK9 and dephosphorylated CDK7. Furthermore, the combination of SNS-032 and Ara-C showed remarkable synergy that was associated with reduced mRNA levels of the antiapoptotic genes XIAP, BCL2 and MCL1. In conclusion, SNS-032 is effective as a single agent and in combination with Ara-C in primary AML blasts. Treatment with Ara-C alone significantly induced the transcription of the antiapoptotic genes BCL2 and XIAP. In contrast, the combination of SNS-032 and Ara-C suppressed the transcription of BCL2, XIAP and MCL1. Therefore, the combination of SNS-032 and Ara-C may increase the sensitivity of AML cells to the cytotoxic effects of Ara-C by inhibiting the transcription of antiapoptotic genes.
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Affiliation(s)
- E Walsby
- Cardiff Experimental Cancer Medicine Centre, Department of Haematology, School of Medicine, Cardiff University, Heath Park, Cardiff, UK.
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Development and validation of a highly sensitive liquid chromatography/mass spectrometry method for simultaneous quantification of lenalidomide and flavopiridol in human plasma. Ther Drug Monit 2010; 30:620-7. [PMID: 18708993 DOI: 10.1097/ftd.0b013e318185813d] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Lenalidomide, an immunomodulatory agent, and flavopiridol, a broad cyclin-dependent kinase inhibitor, are active therapies for clinical use in genomic high-risk chronic lymphocytic leukemia. A high-performance liquid chromatographic assay with tandem mass spectrometric detection has been developed to simultaneously quantify lenalidomide and flavopiridol in human and mouse plasma to facilitate their combined clinical development. Samples were prepared by liquid-liquid extraction with acetonitrile (ACN)-containing internal standard, genistein, followed by evaporation of solvent and reconstitution in 95/5 H2O/ACN. Lenalidomide and internal standard were separated by reversed-phase liquid chromatography on a C-18 column using a gradient of H2O and ACN, each with 0.1% formic acid. Atmospheric pressure chemical ionization in positive ion mode with single reaction monitoring on a triple quadrupole mass spectrometer was applied to detect transitions of lenalidomide (260.06 > 149.10) and flavopiridol (402.09 > 341.02). Lower limits of quantification of lenalidomide and flavopiridol were 1 and 0.3 nM, respectively. Recoveries of lenalidomide and flavopiridol from human plasma ranged from 99% to 116% throughout their linear ranges. Within- and between-run precision and accuracy of replicate samples were all less than 15%. This is the most sensitive analytical method reported to date for both lenalidomide and flavopiridol. This sensitivity will enable late terminal phase concentration measurements and accurate pharmacokinetic parameter estimation in a planned clinical trial with lenalidomide and flavopiridol in patients with chronic lymphocytic leukemia.
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Cell death induction in resting lymphocytes by pan-Cdk inhibitor, but not by Cdk4/6 selective inhibitor. Invest New Drugs 2010; 29:921-31. [PMID: 20524038 DOI: 10.1007/s10637-010-9448-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Accepted: 05/02/2010] [Indexed: 10/19/2022]
Abstract
Immunosuppression is one of the common side effects of many anti-tumor agents targeting proliferating cells. We previously reported the development of a new class of pan-cyclin-dependent kinase (Cdk) inhibitor compounds that induce immunosuppression in rodents. Here, we demonstrated that a pan-Cdk inhibitor, Compound 1 very rapidly reduced white blood cells in mice, only 8 h after administration. Compound 1 induced death of peripheral blood cells or purified resting (non-stimulated) lymphocytes ex vivo. Cell death was induced very rapidly, after 4 h of incubation, suggesting that acute immunosuppression observed in rodents might be, at least in part, due to direct cytotoxic effects of Compound 1 on resting lymphocytes. While cell cycle-related Cdks were not activated, the carboxyl terminal domain (CTD) of the largest subunit of RNA polymerase II was phosphorylated, indicating activation of Cdk7 or Cdk9, which phosphorylates this domain, in resting lymphocytes. Indeed, the pan-Cdk inhibitor suppressed CTD phosphorylation in resting cells at the dose required for cell death induction. Inhibition of Cdk7 or Cdk9 by Compound 1 was also confirmed by suppression of nuclear factor-kappa B (NF-κB)-dependent transcription activity in the human cancer cell line U2OS. Interestingly, a Cdk4/6 inhibitor with selectivity against Cdk7 and Cdk9 did not induce cell death in resting lymphocytes. These results suggest that CTD phosphorylation possibly by Cdk7 or Cdk9 might be important for survival of resting lymphocytes and that Cdk inhibitors without inhibitory activity on these kinases might be an attractive agent for cancer chemotherapy.
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Affiliation(s)
- Mats Ljungman
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA.
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Frew AJ, Johnstone RW, Bolden JE. Enhancing the apoptotic and therapeutic effects of HDAC inhibitors. Cancer Lett 2009; 280:125-33. [PMID: 19359091 DOI: 10.1016/j.canlet.2009.02.042] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Revised: 12/12/2008] [Accepted: 02/16/2009] [Indexed: 10/20/2022]
Abstract
Histone deacetylase inhibitors (HDACi) are anti-cancer drugs that have moved rapidly through clinical development and in 2006 vorinostat (SAHA, Zolinza) was given FDA approval for the treatment of cutaneous T cell lymphoma. Class I, II and IV HDACs that are targets for these compounds deacetylate histone proteins, resulting in chromatin remodelling and altered gene transcription. In addition, numerous non-histone proteins are modified by acetylation and the inhibition of HDAC activity can therefore affect various molecular processes. This broad effect on protein function may account for the pleiotropic anti-tumor responses elicited by HDACi that include induction of tumor cell apoptosis, cell cycle arrest, differentiation and senescence, modulation of immune responses and altered angiogenesis. The ability of HDACi to selectively induce tumor cells to undergo apoptosis is important for the therapeutic efficacy observed in pre-clinical models. Moreover, HDACi can augment the apoptotic effects of other anti-cancer agents that have diverse molecular targets. While HDACi are promising anti-cancer drugs, particularly given the scope to combine HDACi with other agents, identifying the key molecular events that determine the biological response of cells to HDACi treatment remains a challenge. Herein we focus on HDACi-induced apoptosis and discuss the various proteins and pathways that are affected by HDACi to mediate this programmed cell death response. In addition, we highlight the ability of HDACi to synergise with other anti-cancer agents to potently kill tumor cells and discuss the possible molecular processes that underpin the combination effect.
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Affiliation(s)
- Ailsa J Frew
- Cancer Immunology Program, The Peter MacCallum Cancer Centre, Trescowthick Research Laboratories, East Melbourne, Victoria, Australia
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Kang MH, Reynolds CP. Bcl-2 inhibitors: targeting mitochondrial apoptotic pathways in cancer therapy. Clin Cancer Res 2009; 15:1126-32. [PMID: 19228717 DOI: 10.1158/1078-0432.ccr-08-0144] [Citation(s) in RCA: 750] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Defects in apoptotic pathways can promote cancer cell survival and also confer resistance to antineoplastic drugs. One pathway being targeted for antineoplastic therapy is the anti-apoptotic B-cell lymphoma-2 (Bcl-2) family of proteins (Bcl-2, Bcl-XL, Bcl-w, Mcl-1, Bfl1/A-1, and Bcl-B) that bind to and inactivate BH3-domain pro-apoptotic proteins. Signals transmitted by cellular damage (including antineoplastic drugs) or cytokine deprivation can initiate apoptosis via the intrinsic apoptotic pathway. It is controversial whether some BH3-domain proteins (Bim or tBid) directly activate multidomain pro-apoptotic proteins (e.g., Bax and Bak) or act via inhibition of those anti-apoptotic Bcl-2 proteins (Bcl-2, Bcl-XL, Bcl-w, Mcl-1, Bfl1/A-1, and Bcl-B) that stabilize pro-apoptotic proteins. Overexpression of anti-apoptotic Bcl-2 family members has been associated with chemotherapy resistance in various human cancers, and preclinical studies have shown that agents targeting anti-apoptotic Bcl-2 family members have preclinical activity as single agents and in combination with other antineoplastic agents. Clinical trials of several investigational drugs targeting the Bcl-2 family (oblimersen sodium, AT-101, ABT-263, GX15-070) are ongoing. Here, we review the role of the Bcl-2 family in apoptotic pathways and those agents that are known and/or designed to inhibit the anti-apoptotic Bcl-2 family of proteins.
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Affiliation(s)
- Min H Kang
- Cancer Center and the Department of Cell Biology and Biochemistry, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
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Zhang G, Park MA, Mitchell C, Hamed H, Rahmani M, Martin AP, Curiel DT, Yacoub A, Graf M, Lee R, Roberts JD, Fisher PB, Grant S, Dent P. Vorinostat and sorafenib synergistically kill tumor cells via FLIP suppression and CD95 activation. Clin Cancer Res 2008; 14:5385-99. [PMID: 18765530 DOI: 10.1158/1078-0432.ccr-08-0469] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE AND DESIGN Mechanism(s) by which the multikinase inhibitor sorafenib and the histone deacetylase inhibitor vorinostat interact to kill hepatic, renal, and pancreatic adenocarcinoma cells has been defined. RESULTS Low doses of sorafenib and vorinostat interacted in vitro in a synergistic fashion to kill hepatic, renal, and pancreatic adenocarcinoma cells in multiple short-term viability (24-96 h) and in long-term colony formation assays. Cell killing was suppressed by inhibition of cathepsin proteases and caspase-8 and, to a lesser extent, by inhibition of caspase-9. Twenty-four hours after exposure, the activities of extracellular signal-regulated kinase 1/2, AKT, and nuclear factor-kappaB were only modestly modulated by sorafenib and vorinostat treatment. However, 24 h after exposure, sorafenib- and vorinostat-treated cells exhibited markedly diminished expression of c-FLIP-s, full-length BID, BCL-2, BCL-XL, MCL-1, XIAP, increased expression of BIM, and increased activation of BAX, BAK, and BAD. Expression of eIF2alpha S51A blocked sorafenib- and vorinostat-induced suppression of c-FLIP-s levels and overexpression of c-FLIP-s abolished lethality. Sorafenib and vorinostat treatment increased surface levels of CD95 and CD95 association with caspase-8. Knockdown of CD95 or FADD expression significantly reduced sorafenib/vorinostat-mediated lethality. CONCLUSIONS These data show that combined exposure of epithelial tumor cell types to sorafenib and vorinostat diminishes expression of multiple antiapoptotic proteins and promotes activation of the CD95 extrinsic apoptotic and the lysosomal protease pathways, and that suppression of c-FLIP-s expression represents a critical event in transduction of the proapoptotic signals from CD95 to promote mitochondrial dysfunction and death.
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Affiliation(s)
- Guo Zhang
- Department of Biochemistry, Virginia Commonwealth University, Richmond, Virginia 23298-0035, USA
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Ge Y, Byun JS, De Luca P, Gueron G, Yabe IM, Sadiq-Ali SG, Figg WD, Quintero J, Haggerty CM, Li QQ, De Siervi A, Gardner K. Combinatorial antileukemic disruption of oxidative homeostasis and mitochondrial stability by the redox reactive thalidomide 2-(2,4-difluoro-phenyl)-4,5,6,7-tetrafluoro-1H-isoindole-1,3(2H)-dione (CPS49) and flavopiridol. Mol Pharmacol 2008; 74:872-83. [PMID: 18556456 DOI: 10.1124/mol.107.040808] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
2-(2,4-Difluoro-phenyl)-4,5,6,7-tetrafluoro-1H-isoindole-1,3(2H)-dione (CPS49) is a member of a recently identified class of redox-reactive thalidomide analogs that show selective killing of leukemic cells by increasing intracellular reactive oxygen species (ROS) and targeting multiple transcriptional pathways. Flavopiridol is a semisynthetic flavonoid that inhibits cyclin-dependent kinases and also shows selective lethality against leukemic cells. The purpose of this study is to explore the efficacy and mechanism of action of the combinatorial use of the redox-reactive thalidomide CPS49 and the cyclin-dependent kinase inhibitor flavopiridol as a selective antileukemic therapeutic strategy. In combination, CPS49 and flavopiridol were found to induce selective cytotoxicity associated with mitochondrial dysfunction and elevations of ROS in leukemic cells ranging from additive to synergistic activity at low micromolar concentrations. Highest synergy was observed at the level of ROS generation with a strong correlation between cell-specific cytotoxicity and reciprocal coupling of drug-induced ROS elevation with glutathione depletion. Examination of the transcriptional targeting of CPS49 and flavopiridol combinations reveals that the drugs act in concert to initiate a cell specific transcriptional program that manipulates nuclear factor-kappaB (NF-kappaB), E2F-1, and p73 activity to promote enhanced mitochondrial instability by simultaneously elevating the expression of the proapoptotic factors BAX, BAD, p73, and PUMA while depressing expression of the antiapoptotic genes MCL1, XIAP, BCL-xL, SURVIVIN, and MDM2. The coadministration of CPS49 and flavopiridol acts through coordinate targeting of transcriptional pathways that enforce selective mitochondrial dysfunction and ROS elevation and is therefore a promising new therapeutic combination that warrants further preclinical exploration.
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Affiliation(s)
- Yun Ge
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, Bethesda, MD 20892-5065, USA
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A selective sphingosine kinase 1 inhibitor integrates multiple molecular therapeutic targets in human leukemia. Blood 2008; 112:1382-91. [PMID: 18511810 DOI: 10.1182/blood-2008-02-138958] [Citation(s) in RCA: 193] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The potent bioactive sphingolipid mediator, sphingosine-1-phosphate (S1P), is produced by 2 sphingosine kinase isoenzymes, SphK1 and SphK2. Expression of SphK1 is up-regulated in cancers, including leukemia, and associated with cancer progression. A screen of sphingosine analogs identified (2R,3S,4E)-N-methyl-5-(4'-pentylphenyl)-2-aminopent-4-ene-1,3-diol, designated SK1-I (BML-258), as a potent, water-soluble, isoenzyme-specific inhibitor of SphK1. In contrast to pan-SphK inhibitors, SK1-I did not inhibit SphK2, PKC, or numerous other protein kinases. SK1-I decreased growth and survival of human leukemia U937 and Jurkat cells, and enhanced apoptosis and cleavage of Bcl-2. Lethality of SK1-I was reversed by caspase inhibitors and by expression of Bcl-2. SK1-I not only decreased S1P levels but concomitantly increased levels of its proapoptotic precursor ceramide. Conversely, S1P protected against SK1-I-induced apoptosis. SK1-I also induced multiple perturbations in activation of signaling and survival-related proteins, including diminished phosphorylation of ERK1/2 and Akt. Expression of constitutively active Akt protected against SK1-I-induced apoptosis. Notably, SK1-I potently induced apoptosis in leukemic blasts isolated from patients with acute myelogenous leukemia but was relatively sparing of normal peripheral blood mononuclear leukocytes. Moreover, SK1-I markedly reduced growth of AML xenograft tumors. Our results suggest that specific inhibitors of SphK1 warrant attention as potential additions to the therapeutic armamentarium in leukemia.
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Gartel AL. Transcriptional inhibitors, p53 and apoptoss. Biochim Biophys Acta Rev Cancer 2008; 1786:83-6. [PMID: 18503775 DOI: 10.1016/j.bbcan.2008.04.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Revised: 04/24/2008] [Accepted: 04/27/2008] [Indexed: 02/04/2023]
Abstract
Transcriptional inhibitors (TI) repress global transcription and induce apoptosis. It has been suggested that induction of p53 is one of the hallmarks of global transcriptional repression. Two recent papers suggested that treatment of human cancer cells with TIs, leads to p53-dependent, transcription-independent or p53-dependent, transcription-dependent apoptosis. The latter mechanism is linked to the fact that TIs can be selective in their inhibitory effects thereby permitting transcription of some genes. However, the majority of other published data suggest that these drugs induce p53-independent apoptosis. In this article I discuss the mechanisms of TI-dependent cell death and the potential role of p53 in this process.
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Affiliation(s)
- Andrei L Gartel
- Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
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Inoue S, Walewska R, Dyer MJS, Cohen GM. Downregulation of Mcl-1 potentiates HDACi-mediated apoptosis in leukemic cells. Leukemia 2008; 22:819-25. [PMID: 18239621 DOI: 10.1038/leu.2008.1] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mcl-1 is an antiapoptotic Bcl-2 family member, whose degradation is supposedly required for the induction of apoptosis. However, histone deacetylase inhibitors (HDACi) induce apoptosis primarily through the Bak/Mcl-1/Noxa and Bim pathways without decreasing Mcl-1. To investigate this discrepancy, we examined the role of Mcl-1 on HDACi-mediated apoptosis. Inhibition of either class I or class II HDAC by selective HDACi caused an upregulation of Mcl-1 mRNA and protein. Downregulation of Mcl-1 by three structurally unrelated cyclin-dependent kinase inhibitors potentiated HDACi-mediated apoptosis in primary chronic lymphocytic leukemic (CLL) cells and K562 cells. Sensitivity to HDACi-induced apoptosis was increased approximately 10-fold by the cyclin-dependent kinase inhibitors. Nanomolar concentrations of HDACi, approximately 300-fold lower than that required to induce apoptosis alone, sensitized cells to TRAIL, emphasizing that the mechanism(s) whereby HDACi induce apoptosis is clearly distinct from those by which they sensitize to TRAIL. Furthermore, knockdown of Mcl-1-potentiated HDACi-mediated apoptosis in K562 cells. Thus, HDACi-mediated Mcl-1 upregulation plays an important antiapoptotic regulatory role in limiting the efficacy of HDACi-induced apoptosis, which can be overcome by combination with an agent that downregulates Mcl-1. Thus, a clinical trial in some cancers is warranted using a combination of an HDACi with agents that downregulate Mcl-1.
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Affiliation(s)
- S Inoue
- MRC Toxicology Unit, University of Leicester, Leicester, UK
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