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Bajpai P, Banerjee NS, Moore DW, Kim HG, Afaq F, Contreras CM, Heslin MJ, Reddy VB, Peter S, Varambally S, Al Diffalha S, Manne U. Developing 3D Organoid Raft Cultures from Patient-Derived Xenografts as Rapid Models to Screen Efficacy of Experimental Therapeutics. Int J Mol Sci 2022; 23. [PMID: 36430867 DOI: 10.3390/ijms232214392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
Reliable preclinical models are needed for screening new cancer drugs. Thus, we developed an improved 3D tumor organoid model termed "organoid raft cultures" (ORCs). Development of ORCs involved culturing tumors ex vivo on collagen beds (boats) with grid supports to maintain their morphological structure. The ORCs were developed from patient-derived xenografts (PDXs) of colon cancers excised from immune-deficient mice (NOD/SCID/IL2Rgammanull). We utilized these new models to evaluate the efficacy of an investigational drug, Navitoclax (ABT-263). We tested the efficacy of ABT-263, an inhibitor of BCL-2 family proteins, in these ORCs derived from a PDX that showed high expression of antiapoptotic BCL2 family proteins (BCL-2, BCL-XL, and BCL-W). Hematoxylin and eosin staining evaluation of PDXs and corresponding ORCs indicated the retention of morphological and other histological integrity of ORCs. ORCs treated with ABT-263 showed decreased expression of antiapoptotic proteins (BCL2, BCL-XL and BCL-W) and increased proapoptotic proteins (BAX and PUMA), with concomitant activation of caspase 3. These studies support the usefulness of the ORCs, developed from PDXs, as an alternative to PDXs and as faster screening models.
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Cotoraci C, Ciceu A, Sasu A, Miutescu E, Hermenean A. The Anti-Leukemic Activity of Natural Compounds. Molecules 2021; 26:2709. [PMID: 34063044 DOI: 10.3390/molecules26092709] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/26/2021] [Accepted: 04/30/2021] [Indexed: 12/24/2022] Open
Abstract
The use of biologically active compounds has become a realistic option for the treatment of malignant tumors due to their cost-effectiveness and safety. In this review, we aimed to highlight the main natural biocompounds that target leukemic cells, assessed by in vitro and in vivo experiments or clinical studies, in order to explore their therapeutic potential in the treatment of leukemia: acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL). It provides a basis for researchers and hematologists in improving basic and clinical research on the development of new alternative therapies in the fight against leukemia, a harmful hematological cancer and the leading cause of death among patients.
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Tan YQ, Zhang X, Zhang S, Zhu T, Garg M, Lobie PE, Pandey V. Mitochondria: The metabolic switch of cellular oncogenic transformation. Biochim Biophys Acta Rev Cancer 2021; 1876:188534. [PMID: 33794332 DOI: 10.1016/j.bbcan.2021.188534] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 02/06/2023]
Abstract
Mitochondria, well recognized as the "powerhouse" of cells, are maternally inherited organelles with bacterial ancestry that play essential roles in a myriad of cellular functions. It has become profoundly evident that mitochondria regulate a wide array of cellular and metabolic functions, including biosynthetic metabolism, cell signaling, redox homeostasis, and cell survival. Correspondingly, defects in normal mitochondrial functioning have been implicated in various human malignancies. Cancer development involves the activation of oncogenes, inactivation of tumor suppressor genes, and impairment of apoptotic programs in cells. Mitochondria have been recognized as the site of key metabolic switches for normal cells to acquire a malignant phenotype. This review outlines the role of mitochondria in human malignancies and highlights potential aspects of mitochondrial metabolism that could be targeted for therapeutic development.
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Affiliation(s)
- Yan Qin Tan
- Tsinghua Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, PR China; Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China
| | - Xi Zhang
- Shenzhen Bay Laboratory, Shenzhen 518055, Guangdong, PR China
| | - Shuwei Zhang
- Tsinghua Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, PR China
| | - Tao Zhu
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230000, Anhui, PR China; The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230000, Anhui, PR China
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University, Sector-125, Noida 201313, India
| | - Peter E Lobie
- Tsinghua Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, PR China; Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China; Shenzhen Bay Laboratory, Shenzhen 518055, Guangdong, PR China.
| | - Vijay Pandey
- Tsinghua Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, PR China; Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China.
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4
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Abstract
INTRODUCTION Venetoclax, an oral, BCL-2 inhibitor, is approved by the FDA for treatment of CLL in all lines of therapy. Data from landmark studies, including the CLL14 and MURANO trials, demonstrated marked improvement in clinical outcomes compared to chemoimmunotherapy when venetoclax was used in combination with CD20 monoclonal antibodies for fixed treatment duration. AREAS COVERED This article reviews the mechanism of action of venetoclax and discusses how curtailing the BCL signaling pathway undermines CLL pathophysiology. The authors also give their clinical experience with the drug, with emphasis on assessing and managing the risk of venetoclax-associated tumor lysis syndrome (TLS). EXPERT OPINION Venetoclax has positioned itself as one of the primary treatment options for CLL, given the consistent efficacy and deep remissions it has elicited across multiple settings of the disease with a time-limited schedule. Accurate TLS risk evaluation and stringent adherence to the dose-escalation protocols will help optimize patient outcomes. Finally, we expect that current and future studies will (1) ascertain the ideal treatment duration using the minimal residual disease state as a guide and (2) help us understand the optimal role of venetoclax in combination or in sequence with other novel targeted therapies in the treatment of CLL.
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Affiliation(s)
- Lauren Held
- School of Pharmacy, University of Washington, Seattle, WA, USA.,Hematologic Malignancies, Seattle Cancer Care Alliance, Seattle, WA, USA
| | - Chloe Siu
- School of Pharmacy, University of Washington, Seattle, WA, USA.,Hematologic Malignancies, Seattle Cancer Care Alliance, Seattle, WA, USA
| | - Mazyar Shadman
- School of Pharmacy, University of Washington, Seattle, WA, USA.,Hematologic Malignancies, Seattle Cancer Care Alliance, Seattle, WA, USA.,Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
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5
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Liu T, Wu Z, He Y, Xiao Y, Xia C. Single and dual target inhibitors based on Bcl-2: Promising anti-tumor agents for cancer therapy. Eur J Med Chem 2020; 201:112446. [PMID: 32563811 DOI: 10.1016/j.ejmech.2020.112446] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/08/2020] [Accepted: 05/08/2020] [Indexed: 02/07/2023]
Abstract
B-cell lymphoma-2 (Bcl-2) proteins family is an essential checkpoint in apoptosis. Extensive evidences suggested that overexpression of anti-apoptotic Bcl-2 proteins can be observed in multiple cancer cell lines and primary tumor biopsy samples, which is an important reason for tumor cells to evade apoptosis and further acquire drug resistance for chemotherapy. Hence, down-regulation of anti-apoptotic Bcl-2 proteins is effective for the treatment of cancers. In view that Bcl-2 inhibitors and some other anti-tumor agents, such as HDAC inhibitors and Mdm2 inhibitors, exert synergy effects in tumor cells, it is pointed out that dual-targeting therapies based on these targets are regarded as rational strategies to enhance the effectiveness of single target agents for cancer treatment. This review briefly introduces the apoptosis, the structure of Bcl-2 family proteins, and focuses on the current status and recent advances of Bcl-2 inhibitors and the corresponding SARs of them. Moreover, we discuss the synergisms between Bcl-2 and other anti-tumor targets, and summarize the current dual-target agents.
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Yang S, Mao Y, Zhang H, Xu Y, An J, Huang Z. The chemical biology of apoptosis: Revisited after 17 years. Eur J Med Chem 2019; 177:63-75. [PMID: 31129454 DOI: 10.1016/j.ejmech.2019.05.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/30/2019] [Accepted: 05/06/2019] [Indexed: 12/13/2022]
Abstract
A balance of Bcl-2 family proteins dictates cell survival or death, as the interactions between these proteins regulate mitochondrial apoptotic signaling pathways. However, cancer cells frequently show upregulation of pro-survival Bcl-2 proteins and sequester activated pro-apoptotic BH3-only proteins driven by diverse cytotoxic stresses, resulting in tumor progression and chemoresistance. Synthetic molecules from either structure-based design or screening procedures to engage and inactivate pro-survival Bcl-2 proteins and restore apoptotic process represent a chemical biological means of selectively killing malignant cells. 17 years ago, one of us reviewed on the discovery of novel Bcl-2 targeted agents [1]. Here we revisit this area and examine the progress and current status of small molecule Bcl-2 inhibitor development, demonstrating the Bcl-2 family as a valid target for cancer therapy and providing successful examples for the discovery of inhibitors that target protein-protein interactions.
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Dastur A, Choi AH, Costa C, Yin X, Williams A, McClanaghan J, Greenberg M, Roderick J, Patel NU, Boisvert J, McDermott U, Garnett MJ, Almenara J, Grant S, Rizzo K, Engelman JA, Kelliher M, Faber AC, Benes CH. NOTCH1 Represses MCL-1 Levels in GSI-resistant T-ALL, Making them Susceptible to ABT-263. Clin Cancer Res 2018; 25:312-324. [PMID: 30224339 DOI: 10.1158/1078-0432.ccr-18-0867] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 07/19/2018] [Accepted: 09/11/2018] [Indexed: 02/01/2023]
Abstract
PURPOSE Effective targeted therapies are lacking for refractory and relapsed T-cell acute lymphoblastic leukemia (T-ALL). Suppression of the NOTCH pathway using gamma-secretase inhibitors (GSI) is toxic and clinically not effective. The goal of this study was to identify alternative therapeutic strategies for T-ALL. EXPERIMENTAL DESIGN We performed a comprehensive analysis of our high-throughput drug screen across hundreds of human cell lines including 15 T-ALL models. We validated and further studied the top hit, navitoclax (ABT-263). We used multiple human T-ALL cell lines as well as primary patient samples, and performed both in vitro experiments and in vivo studies on patient-derived xenograft models. RESULTS We found that T-ALL are hypersensitive to navitoclax, an inhibitor of BCL2 family of antiapoptotic proteins. Importantly, GSI-resistant T-ALL are also susceptible to navitoclax. Sensitivity to navitoclax is due to low levels of MCL-1 in T-ALL. We identify an unsuspected regulation of mTORC1 by the NOTCH pathway, resulting in increased MCL-1 upon GSI treatment. Finally, we show that pharmacologic inhibition of mTORC1 lowers MCL-1 levels and further sensitizes cells to navitoclax in vitro and leads to tumor regressions in vivo. CONCLUSIONS Our results support the development of navitoclax, as single agent and in combination with mTOR inhibitors, as a new therapeutic strategy for T-ALL, including in the setting of GSI resistance.
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Affiliation(s)
- Anahita Dastur
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - AHyun Choi
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Carlotta Costa
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - Xunqin Yin
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - August Williams
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - Joseph McClanaghan
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - Max Greenberg
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - Justine Roderick
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Neha U Patel
- VCU Philips Institute for Oral Health Research, School of Dentistry and Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia
| | - Jessica Boisvert
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts
| | - Ultan McDermott
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, United Kingdom
| | - Mathew J Garnett
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, United Kingdom
| | - Jorge Almenara
- Department of Anatomic Pathology, Virginia Commonwealth University, Richmond, Virginia
| | - Steven Grant
- Departments of Medicine, Microbiology and Immunology, Biochemistry and Molecular Biology, The Institute for Molecular Medicine and Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia
| | - Kathryn Rizzo
- Department of Anatomic Pathology, Virginia Commonwealth University, Richmond, Virginia
| | - Jeffrey A Engelman
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts.,Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Michelle Kelliher
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Anthony C Faber
- VCU Philips Institute for Oral Health Research, School of Dentistry and Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia
| | - Cyril H Benes
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Massachusetts. .,Department of Medicine, Harvard Medical School, Boston, Massachusetts
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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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Russo M, Milito A, Spagnuolo C, Carbone V, Rosén A, Minasi P, Lauria F, Russo GL. CK2 and PI3K are direct molecular targets of quercetin in chronic lymphocytic leukaemia. Oncotarget 2018; 8:42571-42587. [PMID: 28489572 PMCID: PMC5522089 DOI: 10.18632/oncotarget.17246] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/05/2017] [Indexed: 11/25/2022] Open
Abstract
Despite the encouraging results of the innovative therapeutic treatments, complete remission is uncommon in patients affected by chronic lymphocytic leukaemia, which remains an essentially incurable disease. Recently, clinical trials based on BH3-mimetic drugs showed positive outcomes in subjects with poor prognostic features. However, resistance to treatments occurs in a significant number of patients. We previously reported that the multi-kinase inhibitor quercetin, a natural flavonol, restores sensitivity to ABT-737, a BH3-mimetic compound, in both leukemic cell lines and B-cells isolated from patients. To identify the molecular target of quercetin, we employed a new cell line, HG3, obtained by immortalization of B-cells from a chronic lymphocytic leukaemia patient at the later stage of disease. We confirmed that quercetin in association with ABT-737 synergistically enhances apoptosis in HG3 (combination index < 1 for all fractions affected). We also reported that the cellular uptake of quercetin is extremely rapid, with an intracellular concentration of about 38.5 ng/106 cells, after treatment with 25 μM for 5 min. We demonstrated that the activity of protein kinase CK2, which positively triggers PI3K/Akt pathway by inactivating PTEN phosphatase, is inhibited by quercetin immediately after its addition to HG3 cells (0–2 min). PI3K activity was also inhibited by quercetin within 60 min from the treatment. The combined inhibition of CK2 and PI3K kinase activities by quercetin restored ABT-737 sensitivity and increased lethality in human leukemia cells.
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Affiliation(s)
- Maria Russo
- Institute of Food Sciences, National Research Council, Avellino, Italy
| | - Alfonsina Milito
- Institute of Food Sciences, National Research Council, Avellino, Italy.,Current address: Stazione Zoologica "Anton Dohrn", Villa Comunale, Napoli, Italy
| | - Carmela Spagnuolo
- Institute of Food Sciences, National Research Council, Avellino, Italy
| | - Virginia Carbone
- Institute of Food Sciences, National Research Council, Avellino, Italy
| | - Anders Rosén
- Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, Linköping, Sweden
| | - Paola Minasi
- Institute of Food Sciences, National Research Council, Avellino, Italy
| | - Fabio Lauria
- Institute of Food Sciences, National Research Council, Avellino, Italy
| | - Gian Luigi Russo
- Institute of Food Sciences, National Research Council, Avellino, Italy
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10
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Affiliation(s)
- Riccardo Moia
- Division of Hematology, Department of Translational Medicine, University of Eastern Piedmont, Novara, Italy
| | - Fary Diop
- Division of Hematology, Department of Translational Medicine, University of Eastern Piedmont, Novara, Italy
| | - Chiara Favini
- Division of Hematology, Department of Translational Medicine, University of Eastern Piedmont, Novara, Italy
| | - Ahad Ahmed Kodipad
- Division of Hematology, Department of Translational Medicine, University of Eastern Piedmont, Novara, Italy
| | - Gianluca Gaidano
- Division of Hematology, Department of Translational Medicine, University of Eastern Piedmont, Novara, Italy
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11
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Abstract
OPINION STATEMENT A number of new treatment options have recently emerged for chronic lymphocytic leukemia (CLL) patients, including the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, phosphatidylinositol-3-kinase (PI3K) delta isoform inhibitor idelalisib combined with rituximab, the Bcl-2 antagonist venetoclax, and the new anti-CD20 antibodies obinutuzumab and ofatumumab. Most of these agents are already included into treatment algorithms defined by international practice guidelines, but more clinical investigations are needed to answer still remaining questions. Ibrutinib was proven as a primary choice for patients with the TP53 gene deletion/mutation, who otherwise have no active treatment available. Idelalisib with rituximab is also an active therapy, but due to increased risk of serious infections, its use in first-line treatment is limited to patients for whom ibrutinib is not an option. A new indication for ibrutinib was recently approved for older patients with comorbidities, as an alternative to the already existing indication for chlorambucil with obinutuzumab. The use of kinase inhibitors is already well established in recurrent/refractory disease. Immunochemotherapy with fludarabine, cyclophosphamide, rituximab (FCR) remains a major first-line option for many CLL patients without the TP53 gene deletion/mutation, and who have no significant comorbidities or history of infections, and is particularly effective in patients with favorable features including mutated IGHV status. There are a number of issues regarding novel therapies for CLL that need further investigation such as optimum duration of treatment with kinase inhibitors, appropriate sequencing of novel agents, mechanisms of resistance to inhibitors and response to class switching after treatment failure, along with the potential role of combinations of targeted agents.
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12
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Modi P, Balakrishnan K, Yang Q, Wierda WG, Keating MJ, Gandhi V. Idelalisib and bendamustine combination is synergistic and increases DNA damage response in chronic lymphocytic leukemia cells. Oncotarget 2017; 8:16259-16274. [PMID: 28187444 PMCID: PMC5369961 DOI: 10.18632/oncotarget.15180] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 01/25/2017] [Indexed: 11/25/2022] Open
Abstract
Idelalisib is a targeted agent that potently inhibits PI3Kδ which is exclusively expressed in hematological cells. Bendamustine is a well-tolerated cytotoxic alkylating agent which has been extensively used for treatment of chronic lymphocytic leukemia (CLL). Both these agents are FDA-approved for CLL. To increase the potency of idelalisib and bendamustine, we tested their combination in primary CLL lymphocytes. While each compound alone produced a moderate response, combination at several concentrations resulted in synergistic cytotoxicity. Idelalisib enhanced the bendamustine-mediated DNA damage/repair response, indicated by the phosphorylation of ATM, Chk2, and p53. Each drug alone activated γH2AX but combination treatment further increased the expression of this DNA damage marker. Compared with the control, idelalisib treatment decreased global RNA synthesis, resulting in a decline of early-response and short-lived MCL1 transcripts. In concert, there was a decline in total Mcl-1 protein in CLL lymphocytes. Isogenic mouse embryonic fibroblasts lacking MCL1 had higher sensitivity to bendamustine alone or in combination compared to MCL1 proficient cells. Collectively, these data indicate that bendamustine and idelalisib combination therapy should be investigated for treating patients with CLL.
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Affiliation(s)
- Prexy Modi
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kumudha Balakrishnan
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Qingshan Yang
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - William G Wierda
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Michael J Keating
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Varsha Gandhi
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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14
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Song T, Wang Z, Ji F, Feng Y, Fan Y, Chai G, Li X, Li Z, Zhang Z. Deactivation of Mcl-1 by Dual-Function Small-Molecule Inhibitors Targeting the Bcl-2 Homology 3 Domain and Facilitating Mcl-1 Ubiquitination. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Ting Song
- State Key Laboratory of Fine Chemicals; Zhang Dayu School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Ziqian Wang
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Fangling Ji
- School of Life Science and Technology; Dalian University of Technology; China
| | - Yingang Feng
- Shandong Key Laboratory of Synthetic Biology; CAS Key Laboratory of Biofuels; Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences; Qingdao, Shandong China
| | - Yudan Fan
- School of Life Science and Technology; Dalian University of Technology; China
| | - Gaobo Chai
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Xiangqian Li
- Institute of Oceanology; Chinese Academy of Sciences; Qingdao, Shandong China
| | - Zhiqiang Li
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Zhichao Zhang
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
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15
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Song T, Wang Z, Ji F, Feng Y, Fan Y, Chai G, Li X, Li Z, Zhang Z. Deactivation of Mcl-1 by Dual-Function Small-Molecule Inhibitors Targeting the Bcl-2 Homology 3 Domain and Facilitating Mcl-1 Ubiquitination. Angew Chem Int Ed Engl 2016; 55:14250-14256. [DOI: 10.1002/anie.201606543] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 08/26/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Ting Song
- State Key Laboratory of Fine Chemicals; Zhang Dayu School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Ziqian Wang
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Fangling Ji
- School of Life Science and Technology; Dalian University of Technology; China
| | - Yingang Feng
- Shandong Key Laboratory of Synthetic Biology; CAS Key Laboratory of Biofuels; Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences; Qingdao, Shandong China
| | - Yudan Fan
- School of Life Science and Technology; Dalian University of Technology; China
| | - Gaobo Chai
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Xiangqian Li
- Institute of Oceanology; Chinese Academy of Sciences; Qingdao, Shandong China
| | - Zhiqiang Li
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
| | - Zhichao Zhang
- School of Chemistry; Dalian University of Technology; Dalian, Liaoning China
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16
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Bojarczuk K, Sasi BK, Gobessi S, Innocenti I, Pozzato G, Laurenti L, Efremov DG. BCR signaling inhibitors differ in their ability to overcome Mcl-1–mediated resistance of CLL B cells to ABT-199. Blood 2016; 127:3192-201. [DOI: 10.1182/blood-2015-10-675009] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 04/10/2016] [Indexed: 12/22/2022] Open
Abstract
Key Points
BCR signals induce ABT-199 resistance in CLL cells by upregulating Mcl-1. SYK inhibitors prevent BCR-mediated Mcl-1 induction more effectively than BTK or PI3Kδ inhibitors.
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17
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Freund P, Porpaczy EA, Le T, Gruber M, Pausz C, Staber P, Jäger U, Vanura K. Cannabinoid Receptors Are Overexpressed in CLL but of Limited Potential for Therapeutic Exploitation. PLoS One 2016; 11:e0156693. [PMID: 27248492 PMCID: PMC4889125 DOI: 10.1371/journal.pone.0156693] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 05/18/2016] [Indexed: 12/16/2022] Open
Abstract
The cannabinoid receptors 1 and 2 (CNR1&2) are overexpressed in a variety of malignant diseases and cannabinoids can have noteworthy impact on tumor cell viability and tumor growth. Patients diagnosed with chronic lymphocytic leukemia (CLL) present with very heterogeneous disease characteristics translating into highly differential risk properties. To meet the urgent need for refinement in risk stratification at diagnosis and the search for novel therapies we studied CNR expression and response to cannabinoid treatment in CLL. Expression levels of CNR1&2 were determined in 107 CLL patients by real-time PCR and analyzed with regard to prognostic markers and survival. Cell viability of primary CLL cells was determined in suspension and co-culture after incubation in increasing cannabinoid concentrations under normal and reduced serum conditions and in combination with fludarabine. Impact of cannabinoids on migration of CLL cells towards CXCL12 was determined in transwell plates. We found CNR1&2 to be overexpressed in CLL compared to healthy B-cells. Discriminating between high and low expressing subgroups, only high CNR1 expression was associated with two established high risk markers and conferred significantly shorter overall and treatment free survival. Viability of CLL primary cells was reduced in a dose dependent fashion upon incubation with cannabinoids, however, healthy cells were similarly affected. Under serum reduced conditions, no significant differences were observed within suspension and co-culture, respectively, however, the feeder layer contributed significantly to the survival of CLL cells compared to suspension culture conditions. No significant differences were observed when treating CLL cells with cannabinoids in combination with fludarabine. Interestingly, biologic activity of cannabinoids was independent of both CNR1&2 expression. Finally, we did not observe an inhibition of CXCL12-induced migration by cannabinoids. In contrast to other tumor entities, our data suggest a limited usability of cannabinoids for CLL therapy. Nonetheless, we could define CNR1 mRNA expression as novel prognostic marker.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Coculture Techniques
- Female
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Leukemia, Lymphocytic, Chronic, B-Cell/therapy
- Male
- Middle Aged
- Prognosis
- RNA, Messenger/genetics
- Receptors, Cannabinoid/genetics
- Receptors, Cannabinoid/metabolism
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Affiliation(s)
- Patricia Freund
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Edit A. Porpaczy
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Trang Le
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Michaela Gruber
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Clemens Pausz
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Philipp Staber
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Ulrich Jäger
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Katrina Vanura
- Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
- * E-mail:
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Ren J, Li G, Zhao W, Lin L, Ye T. Norcantharidin combined with ABT-737 for hepatocellular carcinoma: Therapeutic effects and molecular mechanisms. World J Gastroenterol 2016; 22:3962-3968. [PMID: 27099439 PMCID: PMC4823246 DOI: 10.3748/wjg.v22.i15.3962] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 12/30/2015] [Accepted: 01/18/2016] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the therapeutic effect of norcantharidin (NCTD) combined with ABT-737 on hepatocellular carcinoma cells and the molecular mechanism.
METHODS: Two hepatocellular carcinoma (HCC) cell lines, HepG2 and SMMC-7721, were selected. ABT-737 and NCTD were allocated into groups to be used alone or in combination. HepG2 and SMMC-7721 cells were cultured in vitro. Liver cancer cells in the logarithmic phase of growth were vaccinated and cultured to the cell wall stage; these cells were treated for 48 h with different concentrations of NCTD, or ABT-737, or NCTD combined with ABT-737. The cell proliferation inhibition rate was detected by methyl thiazolyl tetrazolium. The expression of Mcl in HCC cells was detected by Western Blotting, and the cells in each group after treatment had apoptosis detected by flow cytometry. The proliferation inhibition rate, the expression of Mcl-1 in cells and the apoptosis inducing effect of treatment were observed in each group, and the effect of NCTD on ABT-737 in the treatment of HCC and its mechanism of action were analyzed.
RESULTS: As the concentration of NCTD increased, the cell proliferation inhibition rate gradually decreased; and the treatment effect of ABT-737 1-3 μm combined with NCTD on cell proliferation inhibition was stronger than that of ABT-737 alone. The difference was statistically significant (P < 0.05). In observing the expression of Mcl-1 in cells after the treatment of different concentrations of NCTD, this was partially inhibited after treatment with NCTD 15 μm, and the expression of Mcl-1 was almost undetectable after treatment with NCTD 30 μm and 60 μm. The effect on inducing apoptosis with the treatment of ABT-737 or NCTD alone for 48 h was lower than that of the control group. The difference was not statistically significant (P > 0.05). The effect on inducing apoptosis in HepG2 and SMMC-7721 cells with the treatment of ABT-737 combined with NCTD for 48 h was greater than that of ABT-737 or NCTD alone. The difference was statistically significant (P < 0.05).
CONCLUSION: NCTD combined with ABT-737 has a positive role in the treatment of HCC, and it has great value in clinical research.
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Abed MN, Abdullah MI, Richardson A. Antagonism of Bcl-XL is necessary for synergy between carboplatin and BH3 mimetics in ovarian cancer cells. J Ovarian Res 2016. [PMID: 27080533 DOI: 10.1186/s13048-016-0234-y] [] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND BH3 mimetics are a class of drugs that antagonize the Bcl-2 family of apoptosis inhibitors. We have previously shown that these compounds can potentiate the activity of carboplatin against several ovarian cancer cell lines. However, recent clinical studies have highlighted that BH3 mimetics which antagonise Bcl-XL are associated with significant thrombocytopenia. This has led to the development of ABT-199 which specifically inhibits Bcl-2. Unfortunately, Bcl-XL appears to be more frequently deregulated in ovarian cancer than Bcl-2. We therefore compared the ability of ABT-199, and the Bcl-XL selective compound WEHI-539, to potentiate the activity of carboplatin in ovarian cancer cell lines. METHODS WEHI-539, ABT-737 and ABT-199 were tested in combination with carboplatin using a panel of 6 ovarian cancer cell lines. The activity of the drugs was evaluated using cell growth assays, staining with trypan bue and measurement of apoptosis by measuring caspase 3/7 activity, PARP cleavage and annexin-V/propidium iodide staining. RESULTS We found that WEHI-539 and ABT-737, but not ABT-199, were synergistic with carboplatin in cell growth assays and potentiated cell death when assessed by trypan blue staining. Furthermore, WEHI-539 and ABT-737 augmented carboplatin induced caspase 3/7 activity, PARP cleavage and annexin V labelling, but ABT-199 failed to do so. CONCLUSIONS These observations suggest that compounds which target Bcl-XL are necessary if BH3 mimetics are to be successfully used to treat patients with ovarian cancer and this highlights the need to develop strategies to minimize thrombocytopenia induced by such compounds.
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Affiliation(s)
- Mohammed Najim Abed
- Institute for Science and Technology in Medicine, Guy Hilton Research Centre, Keele University, Thornburrow Drive, Stoke-on-Trent, ST4 7QB, UK
| | - Marwan Ibrahim Abdullah
- Institute for Science and Technology in Medicine, Guy Hilton Research Centre, Keele University, Thornburrow Drive, Stoke-on-Trent, ST4 7QB, UK
| | - Alan Richardson
- Institute for Science and Technology in Medicine, Guy Hilton Research Centre, Keele University, Thornburrow Drive, Stoke-on-Trent, ST4 7QB, UK. .,School of Pharmacy, Keele University, Keele, ST5 5BG, UK.
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20
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Abed MN, Abdullah MI, Richardson A. Antagonism of Bcl-XL is necessary for synergy between carboplatin and BH3 mimetics in ovarian cancer cells. J Ovarian Res 2016; 9:25. [PMID: 27080533 PMCID: PMC4832520 DOI: 10.1186/s13048-016-0234-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 04/06/2016] [Indexed: 12/18/2022] Open
Abstract
Background BH3 mimetics are a class of drugs that antagonize the Bcl-2 family of apoptosis inhibitors. We have previously shown that these compounds can potentiate the activity of carboplatin against several ovarian cancer cell lines. However, recent clinical studies have highlighted that BH3 mimetics which antagonise Bcl-XL are associated with significant thrombocytopenia. This has led to the development of ABT-199 which specifically inhibits Bcl-2. Unfortunately, Bcl-XL appears to be more frequently deregulated in ovarian cancer than Bcl-2. We therefore compared the ability of ABT-199, and the Bcl-XL selective compound WEHI-539, to potentiate the activity of carboplatin in ovarian cancer cell lines. Methods WEHI-539, ABT-737 and ABT-199 were tested in combination with carboplatin using a panel of 6 ovarian cancer cell lines. The activity of the drugs was evaluated using cell growth assays, staining with trypan bue and measurement of apoptosis by measuring caspase 3/7 activity, PARP cleavage and annexin-V/propidium iodide staining. Results We found that WEHI-539 and ABT-737, but not ABT-199, were synergistic with carboplatin in cell growth assays and potentiated cell death when assessed by trypan blue staining. Furthermore, WEHI-539 and ABT-737 augmented carboplatin induced caspase 3/7 activity, PARP cleavage and annexin V labelling, but ABT-199 failed to do so. Conclusions These observations suggest that compounds which target Bcl-XL are necessary if BH3 mimetics are to be successfully used to treat patients with ovarian cancer and this highlights the need to develop strategies to minimize thrombocytopenia induced by such compounds.
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Affiliation(s)
- Mohammed Najim Abed
- Institute for Science and Technology in Medicine, Guy Hilton Research Centre, Keele University, Thornburrow Drive, Stoke-on-Trent, ST4 7QB, UK
| | - Marwan Ibrahim Abdullah
- Institute for Science and Technology in Medicine, Guy Hilton Research Centre, Keele University, Thornburrow Drive, Stoke-on-Trent, ST4 7QB, UK
| | - Alan Richardson
- Institute for Science and Technology in Medicine, Guy Hilton Research Centre, Keele University, Thornburrow Drive, Stoke-on-Trent, ST4 7QB, UK. .,School of Pharmacy, Keele University, Keele, ST5 5BG, UK.
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Besbes S, Mirshahi M, Pocard M, Billard C. New dimension in therapeutic targeting of BCL-2 family proteins. Oncotarget 2016; 6:12862-71. [PMID: 25970783 PMCID: PMC4536985 DOI: 10.18632/oncotarget.3868] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 04/01/2015] [Indexed: 01/22/2023] Open
Abstract
Proteins of the BCL-2 family control the mitochondrial pathway of apoptosis. Targeting these proteins proves to be an attractive strategy for anticancer therapy. The biological context is based on the fact that BH3-only members of the family are specific antagonists of prosurvival members. This prompted the identification of “BH3 mimetic” compounds. These small peptides or organic molecules indeed mimic the BH3 domain of BH3-only proteins: by selectively binding and antagonizing prosurvival proteins, they can induce apoptosis in malignant cells. Some small-molecule inhibitors of prosurvival proteins have already entered clinical trials in cancer patients and two of them have shown significant therapeutic effects. The latest developments in the field of targeting BCL-2 family proteins highlight several new antagonists of prosurvival proteins as well as direct activators of proapoptotic proteins. These compounds open up novel prospects for the development of BH3 mimetic anticancer drugs.
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Affiliation(s)
- Samaher Besbes
- INSERM U 965, Hôpital Lariboisière, Paris, France.,Université Paris Diderot, UMR S965, Paris, France
| | - Massoud Mirshahi
- INSERM U 965, Hôpital Lariboisière, Paris, France.,Université Paris Diderot, UMR S965, Paris, France
| | - Marc Pocard
- INSERM U 965, Hôpital Lariboisière, Paris, France.,Université Paris Diderot, UMR S965, Paris, France
| | - Christian Billard
- INSERM U 965, Hôpital Lariboisière, Paris, France.,Université Paris Diderot, UMR S965, Paris, France
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ZHENG RUINIAN, YOU ZHIJIAN, JIA JUN, LIN SHUNHUAN, HAN SHUAI, LIU AIXUE, LONG HUIDONG, WANG SENMING. Curcumin enhances the antitumor effect of ABT-737 via activation of the ROS-ASK1-JNK pathway in hepatocellular carcinoma cells. Mol Med Rep 2016; 13:1570-6. [PMID: 26707143 PMCID: PMC4732838 DOI: 10.3892/mmr.2015.4715] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 10/14/2015] [Indexed: 01/07/2023] Open
Abstract
At present, the therapeutic treatment strategies for patients with hepatocellular carcinoma (HCC) remain unsatisfactory, and novel methods are urgently required to treat this disease. Members of the B cell lymphoma (Bcl)-2 family are anti‑apoptotic proteins, which are commonly expressed at high levels in certain HCC tissues and positively correlate with the treatment resistance of patients with HCC. ABT-737, an inhibitor of Bcl-2 anti-apoptotic proteins, has been demonstrated to exhibit potent antitumor effects in several types of tumor, including HCC. However, treatment with ABT-737 alone also activates certain pro-survival signaling pathways, which attenuate the antitumor validity of ABT-737. Curcumin, which is obtained from Curcuma longa, is also an antitumor potentiator in multiple types of cancer. In the present study, the synergistic effect of curcumin and ABT-737 on HCC cells was investigated for the first time, to the best of our knowledge. It was found that curcumin markedly enhanced the antitumor effects of ABT-737 on HepG2 cells, which was partially dependent on the induction of apoptosis, according to western blot analysis and flow cytometric apoptosis analysis. In addition, the sustained activation of the ROS-ASK1-c-Jun N-terminal kinase pathway may be an important mediator of the synergistic effect of curcumin and ABT-737. Collectively, these results indicated that the combination of curcumin and ABT-737 can efficaciously induce the death of HCC cells, and may offer a potential treatment strategy for patients with HCC.
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Affiliation(s)
- RUINIAN ZHENG
- Department of Oncology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China,Department of Oncology, Dongguan People's Hospital, Dongguan, Guangdong 523000, P.R. China
| | - ZHIJIAN YOU
- Department of Oncology, Dongguan People's Hospital, Dongguan, Guangdong 523000, P.R. China
| | - JUN JIA
- Department of Oncology, Dongguan People's Hospital, Dongguan, Guangdong 523000, P.R. China
| | - SHUNHUAN LIN
- Department of Oncology, Dongguan People's Hospital, Dongguan, Guangdong 523000, P.R. China
| | - SHUAI HAN
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - AIXUE LIU
- Department of Oncology, The Second People's Hospital of Shenzhen, Shenzhen, Guangdong 518035, P.R. China
| | - HUIDONG LONG
- Department of Internal Medicine, Affiliated Cancer Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510095, P.R. China
| | - SENMING WANG
- Department of Oncology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China,Correspondence to: Dr Senming Wang, Department of Oncology, Zhujiang Hospital, Southern Medical University, 253 Middle Industrial Avenue, Guangzhou, Guangdong 510282, P.R. China, E-mail:
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Cervantes-Gomez F, Lamothe B, Woyach JA, Wierda WG, Keating MJ, Balakrishnan K, Gandhi V. Pharmacological and Protein Profiling Suggests Venetoclax (ABT-199) as Optimal Partner with Ibrutinib in Chronic Lymphocytic Leukemia. Clin Cancer Res 2015; 21:3705-15. [PMID: 25829398 DOI: 10.1158/1078-0432.ccr-14-2809] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 03/18/2015] [Indexed: 12/21/2022]
Abstract
PURPOSE Bruton's tyrosine kinase (BTK) is a critical enzyme in the B-cell receptor pathway and is inhibited by ibrutinib due to covalent binding to the kinase domain. Though ibrutinib results in impressive clinical activity in chronic lymphocytic leukemia (CLL), most patients achieve only partial remission due to residual disease. We performed a pharmacologic profiling of residual circulating CLL cells from patients receiving ibrutinib to identify optimal agents that could induce cell death of these lymphocytes. EXPERIMENTAL DESIGN Ex vivo serial samples of CLL cells from patients on ibrutinib were obtained prior and after (weeks 2, 4, and 12) the start of treatment. These cells were incubated with PI3K inhibitors (idelalisib or IPI-145), bendamustine, additional ibrutinib, or BCL-2 antagonists (ABT-737 or ABT-199), and cell death was measured. In vitro investigations complemented ex vivo studies. Immunoblots for BTK signaling pathway and antiapoptotic proteins were performed. RESULTS The BCL-2 antagonists, especially ABT-199, induced high cell death during ex vivo incubations. In concert with the ex vivo data, in vitro combinations also resulted in high cytotoxicity. Serial samples of CLL cells obtained before and 2, 4, 12, or 36 weeks after the start of ibrutinib showed inhibition of BTK activity and sensitivity to ABTs. Among the three BCL-2 family antiapoptotic proteins that are overexpressed in CLL, levels of MCL-1 and BCL-XL were decreased after ibrutinib while ABT-199 selectively antagonizes BCL-2. CONCLUSIONS Our biologic and molecular results suggest that ibrutinib and ABT-199 combination should be tested clinically against CLL.
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Affiliation(s)
| | - Betty Lamothe
- Department of Experimental Therapeutics, MD Anderson Cancer Center, Houston, Texas
| | | | - William G Wierda
- Department of Leukemia, MD Anderson Cancer Center, Houston, Texas
| | | | - Kumudha Balakrishnan
- Department of Experimental Therapeutics, MD Anderson Cancer Center, Houston, Texas
| | - Varsha Gandhi
- Department of Experimental Therapeutics, MD Anderson Cancer Center, Houston, Texas. Department of Leukemia, MD Anderson Cancer Center, Houston, Texas.
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Alhosin M, León-González AJ, Dandache I, Lelay A, Rashid SK, Kevers C, Pincemail J, Fornecker LM, Mauvieux L, Herbrecht R, Schini-Kerth VB. Bilberry extract (Antho 50) selectively induces redox-sensitive caspase 3-related apoptosis in chronic lymphocytic leukemia cells by targeting the Bcl-2/Bad pathway. Sci Rep 2015; 5:8996. [PMID: 25757575 DOI: 10.1038/srep08996] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 01/29/2015] [Indexed: 12/22/2022] Open
Abstract
Defect in apoptosis has been implicated as a major cause of resistance to chemotherapy observed in B cell chronic lymphocytic leukaemia (B CLL). This study evaluated the pro-apoptotic effect of an anthocyanin-rich dietary bilberry extract (Antho 50) on B CLL cells from 30 patients and on peripheral blood mononuclear cells (PBMCs) from healthy subjects, and determined the underlying mechanism. Antho 50 induced concentration- and time-dependent pro-apoptotic effects in B CLL cells but little or no effect in PBMCs. Among the main phenolic compounds of the bilberry extract, delphinidin-3-O-glucoside and delphinidin-3-O-rutinoside induced a pro-apoptotic effect. Antho 50-induced apoptosis is associated with activation of caspase 3, down-regulation of UHRF1, a rapid dephosphorylation of Akt and Bad, and down-regulation of Bcl-2. Antho 50 significantly induced PEG-catalase-sensitive formation of reactive oxygen species in B CLL cells. PEG-catalase prevented the Antho 50-induced induction of apoptosis and related signaling. The present findings indicate that Antho 50 exhibits strong pro-apoptotic activity through redox-sensitive caspase 3 activation-related mechanism in B CLL cells involving dysregulation of the Bad/Bcl-2 pathway. This activity of Antho 50 involves the glucoside and rutinoside derivatives of delphinidin. They further suggest that Antho 50 has chemotherapeutic potential by targeting selectively B CLL cells.
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Abstract
Natural products have been a rich source of compounds for drug discovery. However, their use has diminished in the past two decades, in part because of technical barriers to screening natural products in high-throughput assays against molecular targets. Here, we review strategies for natural product screening that harness the recent technical advances that have reduced these barriers. We also assess the use of genomic and metabolomic approaches to augment traditional methods of studying natural products, and highlight recent examples of natural products in antimicrobial drug discovery and as inhibitors of protein-protein interactions. The growing appreciation of functional assays and phenotypic screens may further contribute to a revival of interest in natural products for drug discovery.
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Affiliation(s)
- Alan L Harvey
- 1] Research and Innovation Support, Dublin City University, Dublin 9, Ireland. [2] Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow G4 0NR, UK
| | - RuAngelie Edrada-Ebel
- Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow G4 0NR, UK
| | - Ronald J Quinn
- Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland 4111, Australia
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Zhang CC, Gdynia G, Ehemann V, Roth W. The HMGB1 protein sensitizes colon carcinoma cells to cell death triggered by pro-apoptotic agents. Int J Oncol 2014; 46:667-76. [PMID: 25434832 DOI: 10.3892/ijo.2014.2785] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 11/06/2014] [Indexed: 11/06/2022] Open
Abstract
The HMGB1 protein has multiple functions in tumor biology and can act both as a transcription factor and as a cytokine. HMGB1 is released during cell death, and in our previous studies we demonstrated that HMGB1 induces a distinct, necrosis-like cell death in glioblastoma. In epithelial malignant tumors such as colorectal cancer (CRC), the HMGB1-dependent effects show cross-talk with apoptotic signal transduction. Treatment of CRC cells with low concentrations of recombinant HMGB1 results in dose-dependent cytotoxicity which is morphologically characterized by the formation of giant mitochondria and does not share features of apoptosis. HMGB1-triggered cell death is associated with intracellular ROS release, and overexpression of Bcl-2 blocks both the increase of ROS as well as HMGB1-dependent cell death. Importantly, treatment with recombinant HMGB1 or overexpression of endogenous HMGB1 strongly sensitizes CRC cells to the cytotoxic activity of the pro-apoptotic death ligand TRAIL as well as the small molecule Bcl-2 family inhibitor ABT‑737. Moreover, treatment of CRC cells with TRAIL or ABT‑737 induces a release of endogenous HMGB1 into the extracellular space, and preincubation with glycyrrhizin, an HMGB1 inhibitor, significantly inhibits induction of cell death by TRAIL and ABT‑737, suggesting that HMGB1 functionally contributes to the execution of cell death triggered by pro-apoptotic agents. Finally, we investigated the expression of HMGB1 in human CRC tumor samples and found that loss of HMGB1 expression is associated with a more aggressive phenotype and a more advanced stage of disease in patients with CRC. Altogether, our findings demonstrate a functional link between cytotoxic signaling cascades triggered by HMGB1 and pro-apoptotic agents leading to an HMGB1-dependent sensitization to CRC cell death. Thus, a further evaluation of recombinant HMGB1 as part of an experimental combination treatment of CRC seems warranted.
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Affiliation(s)
- Chengcheng Christine Zhang
- Molecular Tumor Pathology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | - Georg Gdynia
- Molecular Tumor Pathology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | - Volker Ehemann
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 224, D-69120 Heidelberg, Germany
| | - Wilfried Roth
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 224, D-69120 Heidelberg, Germany
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27
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Tadmor T, Shvidel L, Bairey O, Goldschmidt N, Ruchlemer R, Fineman R, Rahimi-Levene N, Herishanu Y, Yuklea M, Arad A, Aviv A, Polliack A. Richter's transformation to diffuse large B-cell lymphoma: a retrospective study reporting clinical data, outcome, and the benefit of adding rituximab to chemotherapy, from the Israeli CLL Study Group. Am J Hematol 2014; 89:E218-22. [PMID: 25110869 DOI: 10.1002/ajh.23826] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 07/17/2014] [Accepted: 08/06/2014] [Indexed: 11/10/2022]
Abstract
Richter's syndrome (RS) is the rare development of an aggressive lymphoid malignancy in a patient with pre-existing chronic lymphocytic leukemia (CLL). Data on RS is sparse and mostly derived from case reports or small series of patients and only a few larger cohorts have been published. The purpose of this large retrospective study was to summarize our national experience with RS in CLL, examine possible risk factors, and analyze relevant demographic, laboratory and clinical parameters, including results of therapy and outcome. We first evaluated data obtained from 119 patients with RS diagnosed during 1971-2010 from 12 medical centers in Israel. The final cohort summarized consisted of 81 patients with RS who developed only diffuse large B-cell lymphoma (DLBCL) after exclusion all cases with insufficient data and those who were not DLBCL. Median overall survival from time of diagnosis of RS was 8 months; after applying the Richter score, patients could be stratified into three prognostic groups, while all other clinical and laboratory parameters evaluated had no prognostic significance. Prior therapy for CLL had no impact on RS survival (P = 0.8) and patients with therapy "naïve" RS and those who had already received chemotherapy prior to developing RS, had the same survival. The addition of rituximab to chemotherapy for RS improved 2 years overall survival from 19% in the chemotherapy alone arm to 42% (P value of 0.001). Although prognosis of patients with RS remains dismal, this retrospective observation provides support for the use of chemo-immunotherapy in DLBCL-RS.
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Affiliation(s)
- Tamar Tadmor
- Hematology Unit, Bnai-Zion Medical Center; Haifa
| | - Lev Shvidel
- Department of Hematology; Kaplan Medical Center; Rehovot
| | - Osnat Bairey
- Department of Hematology; Rabin Medical Center, Petah-Tikva and Sackler Faculty of Medicine, Tel Aviv University; Tel Aviv
| | - Neta Goldschmidt
- Department of Hematology; Hadassah University Hospital; Jerusalem
| | - Rosa Ruchlemer
- Hematology Department; Shaare Zedek Medical Center; Jerusalem
| | - Riva Fineman
- Department of Hematology and Bone Marrow Transplantation; Rambam Health Care Campus; Haifa
| | | | - Yair Herishanu
- Department of Hematology; Sourasky Medical Center; Tel-Aviv
| | - Mona Yuklea
- Hematology Department; Meir Medical Center; Kfar-Saba
| | - Ariela Arad
- Hematology department; Sanz Medical Center Laniado Hospital; Natanya
| | | | - Aaron Polliack
- Department of Hematology; Hadassah University Hospital; Jerusalem
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Szwed M, Laroche-Clary A, Robert J, Jozwiak Z. Induction of apoptosis by doxorubicin-transferrin conjugate compared to free doxorubicin in the human leukemia cell lines. Chem Biol Interact 2014; 220:140-8. [PMID: 24998637 DOI: 10.1016/j.cbi.2014.06.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 05/31/2014] [Accepted: 06/16/2014] [Indexed: 10/25/2022]
Abstract
In our research we compared the effect of doxorubicin (DOX) and doxorubicin-transferrin (DOX-TRF) conjugate on the induction of programmed cell death. All experiments were carried out on human leukemia cells: CCRF-CEM, K562 sensitive and resistant to DOX, (K562/DOX), which are the molecular model for the chronic and acute form of hematological malignancies, respectively. At the same time, studies were also performed on normal, peripheral blood mononuclear cells (PBMCs). The first stages of apoptosis, connected with externalization of phosphatidylserine (PS), were evaluated after comparing the viability of tested cell lines treated with DOX-TRF conjugate or free DOX. Morphological changes of nuclei connected with apoptosis were analyzed by double staining Hoechst 33258/propidium iodide. Subsequently, we conducted a more accurate evaluation of DOX-TRF-trigged cell death by using DNA ladder assay, measuring the activation of caspase-3, -8 and -9 and changes in poly-ADP ribose polymerase (PARP) activity. The percentage of apoptotic cells reached its maximum at 24 and 48 h incubation. Prolonged treatment time with DOX-TRF conjugate progressively increased the level of necrotic cells. At 24-48 h time points, we observed a significant increase in the activity of apoptosis-characterized enzymes (caspases -8, -9, -3). This study provided the evidence that DOX-TRF conjugate triggers apoptotic pathway connected with DNA damage mediated by the activation of pro-caspases and PARP cleavage.
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Affiliation(s)
- Marzena Szwed
- Department of Thermobiology, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143 Street, 90-236 Lodz, Poland.
| | - Audrey Laroche-Clary
- INSERM U916, Institut Bergonié, Université Bordeaux Segalen, 33076 Bordeaux, France
| | - Jacques Robert
- INSERM U916, Institut Bergonié, Université Bordeaux Segalen, 33076 Bordeaux, France
| | - Zofia Jozwiak
- Department of Thermobiology, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143 Street, 90-236 Lodz, Poland
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Affiliation(s)
- Michael Plötz
- Department of Dermatology, Venerology and Allergology; HTCC - Skin Cancer Center; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Jürgen Eberle
- Department of Dermatology, Venerology and Allergology; HTCC - Skin Cancer Center; Charité - Universitätsmedizin Berlin; Berlin Germany
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30
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Hassig CA, Zeng FY, Kung P, Kiankarimi M, Kim S, Diaz PW, Zhai D, Welsh K, Morshedian S, Su Y, O'Keefe B, Newman DJ, Rusman Y, Kaur H, Salomon CE, Brown SG, Baire B, Michel AR, Hoye TR, Francis S, Georg GI, Walters MA, Divlianska DB, Roth GP, Wright AE, Reed JC. Ultra-High-Throughput Screening of Natural Product Extracts to Identify Proapoptotic Inhibitors of Bcl-2 Family Proteins. ACTA ACUST UNITED AC 2014; 19:1201-11. [PMID: 24870016 DOI: 10.1177/1087057114536227] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 04/26/2014] [Indexed: 12/30/2022]
Abstract
Antiapoptotic Bcl-2 family proteins are validated cancer targets composed of six related proteins. From a drug discovery perspective, these are challenging targets that exert their cellular functions through protein-protein interactions (PPIs). Although several isoform-selective inhibitors have been developed using structure-based design or high-throughput screening (HTS) of synthetic chemical libraries, no large-scale screen of natural product collections has been reported. A competitive displacement fluorescence polarization (FP) screen of nearly 150,000 natural product extracts was conducted against all six antiapoptotic Bcl-2 family proteins using fluorochrome-conjugated peptide ligands that mimic functionally relevant PPIs. The screens were conducted in 1536-well format and displayed satisfactory overall HTS statistics, with Z'-factor values ranging from 0.72 to 0.83 and a hit confirmation rate between 16% and 64%. Confirmed active extracts were orthogonally tested in a luminescent assay for caspase-3/7 activation in tumor cells. Active extracts were resupplied, and effort toward the isolation of pure active components was initiated through iterative bioassay-guided fractionation. Several previously described altertoxins were isolated from a microbial source, and the pure compounds demonstrate activity in both Bcl-2 FP and caspase cellular assays. The studies demonstrate the feasibility of ultra-high-throughput screening using natural product sources and highlight some of the challenges associated with this approach.
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Affiliation(s)
| | - Fu-Yue Zeng
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | - Paul Kung
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | | | - Sylvia Kim
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | - Paul W Diaz
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | - Dayong Zhai
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | - Kate Welsh
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | | | - Ying Su
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA
| | | | | | - Yudi Rusman
- Center for Drug Design, University of Minnesota, Minneapolis, MN, USA
| | - Harneet Kaur
- Center for Drug Design, University of Minnesota, Minneapolis, MN, USA
| | | | - Susan G Brown
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Beeraiah Baire
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Andrew R Michel
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Thomas R Hoye
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Subhashree Francis
- Institute for Therapeutics Discovery and Development, Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Gunda I Georg
- Institute for Therapeutics Discovery and Development, Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Michael A Walters
- Institute for Therapeutics Discovery and Development, Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | | | - Gregory P Roth
- Sanford-Burnham Medical Research Institute at Lake Nona, Orlando, FL, USA
| | - Amy E Wright
- Harbor Branch Oceanographic Institute at Florida Atlantic University, Fort Pierce, FL, USA
| | - John C Reed
- Sanford Burnham Medical Research Institute, La Jolla, CA, USA Roche Pharmaceuticals, Basel, Switzerland
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31
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Soderquist RS, Danilov AV, Eastman A. Gossypol increases expression of the pro-apoptotic BH3-only protein NOXA through a novel mechanism involving phospholipase A2, cytoplasmic calcium, and endoplasmic reticulum stress. J Biol Chem 2014; 289:16190-9. [PMID: 24778183 DOI: 10.1074/jbc.m114.562900] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Gossypol is a putative BH3 mimetic proposed to inhibit BCL2 and BCLXL based on cell-free assays. We demonstrated previously that gossypol failed to directly inhibit BCL2 in cells or induce apoptosis in chronic lymphocytic leukemia (CLL) cells or platelets, which require BCL2 or BCLXL, respectively, for survival. Here, we demonstrate that gossypol rapidly increased activity of phospholipase A2 (PLA2), which led to an increase in cytoplasmic calcium, endoplasmic reticulum (ER) stress, and up-regulation of the BH3-only protein NOXA. Pretreatment with the PLA2 inhibitor, aristolochic acid, abrogated the increase in calcium, ER stress, and NOXA. Calcium chelation also abrogated the gossypol-induced increase in calcium, ER stress, and NOXA, but not the increase in PLA2 activity, indicating that PLA2 is upstream of these events. In addition, incubating cells with the two products of PLA2 (lysophosphatidic acid and arachidonic acid) mimicked treatment with gossypol. NOXA is a pro-apoptotic protein that functions by binding the BCL2 family proteins MCL1 and BFL1. The BCL2 inhibitor ABT-199 is currently in clinical trials for CLL. Resistance to ABT-199 can occur from up-regulation of other BCL2 family proteins, and this resistance can be mimicked by culturing CLL cells on CD154(+) stroma cells. We report here that AT-101, a derivative of gossypol in clinical trials, overcomes stroma-mediated resistance to ABT-199 in primary CLL cells, suggesting that a combination of these drugs may be efficacious in the clinic.
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Affiliation(s)
| | - Alexey V Danilov
- Medicine and the Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756
| | - Alan Eastman
- From the Departments of Pharmacology and Toxicology and the Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756
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Moldoveanu T, Follis AV, Kriwacki RW, Green DR. Many players in BCL-2 family affairs. Trends Biochem Sci 2014; 39:101-11. [PMID: 24503222 DOI: 10.1016/j.tibs.2013.12.006] [Citation(s) in RCA: 309] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 12/19/2013] [Accepted: 12/27/2013] [Indexed: 01/08/2023]
Abstract
During apoptotic cell death, cellular stress signals converge at the mitochondria to induce mitochondrial outer-membrane permeabilization (MOMP) through B cell lymphoma-2 (BCL-2) family proteins and their effectors. BCL-2 proteins function through protein-protein interactions, the mechanisms and structural aspects of which are only now being uncovered. Recently, the elucidation of the dynamic features underlying their function has highlighted their structural plasticity and the consequent complex thermodynamic landscape governing their protein-protein interactions. These studies show that canonical interactions involve a conserved, hydrophobic groove, whereas non-canonical interactions function allosterically outside the groove. We review the latest structural advances in understanding the interactions and functions of mammalian BCL-2 family members, and discuss new opportunities to modulate these proteins in health and disease.
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Affiliation(s)
- Tudor Moldoveanu
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Ariele Viacava Follis
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Richard W Kriwacki
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Douglas R Green
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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