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Duggan NN, Dragic T, Chanda SK, Pache L. Breaking the Silence: Regulation of HIV Transcription and Latency on the Road to a Cure. Viruses 2023; 15:2435. [PMID: 38140676 PMCID: PMC10747579 DOI: 10.3390/v15122435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/12/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023] Open
Abstract
Antiretroviral therapy (ART) has brought the HIV/AIDS epidemic under control, but a curative strategy for viral eradication is still needed. The cessation of ART results in rapid viral rebound from latently infected CD4+ T cells, showing that control of viral replication alone does not fully restore immune function, nor does it eradicate viral reservoirs. With a better understanding of factors and mechanisms that promote viral latency, current approaches are primarily focused on the permanent silencing of latently infected cells ("block and lock") or reactivating HIV-1 gene expression in latently infected cells, in combination with immune restoration strategies to eliminate HIV infected cells from the host ("shock and kill"). In this review, we provide a summary of the current, most promising approaches for HIV-1 cure strategies, including an analysis of both latency-promoting agents (LPA) and latency-reversing agents (LRA) that have shown promise in vitro, ex vivo, and in human clinical trials to reduce the HIV-1 reservoir.
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Affiliation(s)
- Natasha N. Duggan
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Tatjana Dragic
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Sumit K. Chanda
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Lars Pache
- NCI Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
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2
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Aquino A, Bianchi N, Terrazzan A, Franzese O. Protein Kinase C at the Crossroad of Mutations, Cancer, Targeted Therapy and Immune Response. BIOLOGY 2023; 12:1047. [PMID: 37626933 PMCID: PMC10451643 DOI: 10.3390/biology12081047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023]
Abstract
The frequent PKC dysregulations observed in many tumors have made these enzymes natural targets for anticancer applications. Nevertheless, this considerable interest in the development of PKC modulators has not led to the expected therapeutic benefits, likely due to the complex biological activities regulated by PKC isoenzymes, often playing ambiguous and protective functions, further driven by the occurrence of mutations. The structure, regulation and functions of PKCs have been extensively covered in other publications. Herein, we focused on PKC alterations mostly associated with complete functional loss. We also addressed the modest yet encouraging results obtained targeting PKC in selected malignancies and the more frequent negative clinical outcomes. The reported observations advocate the need for more selective molecules and a better understanding of the involved pathways. Furthermore, we underlined the most relevant immune mechanisms controlled by PKC isoforms potentially impacting the immune checkpoint inhibitor blockade-mediated immune recovery. We believe that a comprehensive examination of the molecular features of the tumor microenvironment might improve clinical outcomes by tailoring PKC modulation. This approach can be further supported by the identification of potential response biomarkers, which may indicate patients who may benefit from the manipulation of distinctive PKC isoforms.
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Affiliation(s)
- Angelo Aquino
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy;
| | - Nicoletta Bianchi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (N.B.); (A.T.)
| | - Anna Terrazzan
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (N.B.); (A.T.)
- Laboratory for Advanced Therapy Technologies (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Ornella Franzese
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy;
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3
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Tian Z, Lu XT, Jiang X, Tian J. Bryostatin-1: a promising compound for neurological disorders. Front Pharmacol 2023; 14:1187411. [PMID: 37351510 PMCID: PMC10282138 DOI: 10.3389/fphar.2023.1187411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 05/23/2023] [Indexed: 06/24/2023] Open
Abstract
The central nervous system (CNS) is the most complex system in human body, and there is often a lack of effective treatment strategies for the disorders related with CNS. Natural compounds with multiple pharmacological activities may offer better options because they have broad cellular targets and potentially produce synergic and integrative effects. Bryostatin-1 is one of such promising compounds, a macrolide separated from marine invertebrates. Bryostatin-1 has been shown to produce various biological activities through binding with protein kinase C (PKC). In this review, we mainly summarize the pharmacological effects of bryostatin-1 in the treatment of multiple neurological diseases in preclinical studies and clinical trials. Bryostatin-1 is shown to have great therapeutic potential for Alzheimer's disease, multiple sclerosis, fragile X syndrome, stroke, traumatic brain injury, and depression. It exhibits significant rescuing effects on the deficits of spatial learning, cognitive function, memory and other neurological functions caused by diseases, producing good neuroprotective effects. The promising neuropharmacological activities of bryostatin-1 suggest that it is a potential candidate for the treatment of related neurological disorders although there are still some issues needed to be addressed before its application in clinic.
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Affiliation(s)
- Zhen Tian
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
| | - Xin-Tong Lu
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
| | - Xun Jiang
- Department of Pediatrics, Tangdu Hospital of Fourth Military Medical University, Xi’an, China
| | - Jiao Tian
- Department of Infection, Children’s Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Child Infection and Immunity, The First Batch of Key Disciplines on Public Health in Chongqing, Chongqing, China
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4
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Anderko RR, Mailliard RB. Mapping the interplay between NK cells and HIV: therapeutic implications. J Leukoc Biol 2023; 113:109-138. [PMID: 36822173 PMCID: PMC10043732 DOI: 10.1093/jleuko/qiac007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Indexed: 01/18/2023] Open
Abstract
Although highly effective at durably suppressing plasma HIV-1 viremia, combination antiretroviral therapy (ART) treatment regimens do not eradicate the virus, which persists in long-lived CD4+ T cells. This latent viral reservoir serves as a source of plasma viral rebound following treatment interruption, thus requiring lifelong adherence to ART. Additionally, challenges remain related not only to access to therapy but also to a higher prevalence of comorbidities with an inflammatory etiology in treated HIV-1+ individuals, underscoring the need to explore therapeutic alternatives that achieve sustained virologic remission in the absence of ART. Natural killer (NK) cells are uniquely positioned to positively impact antiviral immunity, in part due to the pleiotropic nature of their effector functions, including the acquisition of memory-like features, and, therefore, hold great promise for transforming HIV-1 therapeutic modalities. In addition to defining the ability of NK cells to contribute to HIV-1 control, this review provides a basic immunologic understanding of the impact of HIV-1 infection and ART on the phenotypic and functional character of NK cells. We further delineate the qualities of "memory" NK cell populations, as well as the impact of HCMV on their induction and subsequent expansion in HIV-1 infection. We conclude by highlighting promising avenues for optimizing NK cell responses to improve HIV-1 control and effect a functional cure, including blockade of inhibitory NK receptors, TLR agonists to promote latency reversal and NK cell activation, CAR NK cells, BiKEs/TriKEs, and the role of HIV-1-specific bNAbs in NK cell-mediated ADCC activity against HIV-1-infected cells.
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Affiliation(s)
- Renee R. Anderko
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States
| | - Robbie B. Mailliard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States
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5
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Activators and Inhibitors of Protein Kinase C (PKC): Their Applications in Clinical Trials. Pharmaceutics 2021; 13:pharmaceutics13111748. [PMID: 34834162 PMCID: PMC8621927 DOI: 10.3390/pharmaceutics13111748] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/18/2021] [Accepted: 10/19/2021] [Indexed: 02/05/2023] Open
Abstract
Protein kinase C (PKC), a family of phospholipid-dependent serine/threonine kinase, is classed into three subfamilies based on their structural and activation characteristics: conventional or classic PKC isozymes (cPKCs; α, βI, βII, and γ), novel or non-classic PKC isozymes (nPKCs; δ, ε, η, and θ), and atypical PKC isozymes (aPKCs; ζ, ι, and λ). PKC inhibitors and activators are used to understand PKC-mediated intracellular signaling pathways and for the diagnosis and treatment of various PKC-associated diseases, such as cancers, neurological diseases, cardiovascular diseases, and infections. Many clinical trials of PKC inhibitors in cancers showed no significant clinical benefits, meaning that there is a limitation to design a cancer therapeutic strategy targeting PKC alone. This review will focus on the activators and inhibitors of PKC and their applications in clinical trials.
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6
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Raghuvanshi R, Bharate SB. Preclinical and Clinical Studies on Bryostatins, A Class of Marine-Derived Protein Kinase C Modulators: A Mini-Review. Curr Top Med Chem 2021; 20:1124-1135. [PMID: 32209043 DOI: 10.2174/1568026620666200325110444] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 02/11/2020] [Accepted: 02/24/2020] [Indexed: 12/20/2022]
Abstract
Bryostatins are complex macrolactones isolated from marine organisms Bryozoan Bugula neritina. They are potent modulators of protein kinase C isozymes (PKCα: ki = 1.3-188 nM), and are one of the most extensively investigated marine natural products in clinical trials. Although ~21 natural bryostatins have been isolated, however only bryostatin-1 (1) has received much interest among medicinal chemists and clinicians. The structure-activity relationship of bryostatins has been well established, with the identification of key pharmacophoric features important for PKC modulation. The low natural abundance and the long synthetic route have prompted medicinal chemists to come-up with simplified analogs. Bryostatin skeleton comprises three pyran rings connected to each other to form a macrocyclic lactone. The simplest analog 27 contains only one pyran, which is also able to modulate the PKCα activity; however, the cyclic framework appears to be essential for the desired level of potency. Another simplified analog 17 ("picolog") exhibited potent and in-vivo efficacy against lymphoma. Bryostatin-1 (1) has shown an acceptable intravenous pharmacokinetic profile in mice and displayed promising in-vivo efficacy in mice models of various cancers and Alzheimer's disease. Bryostatin-1 was investigated in numerous Phase I/II oncology clinical trials; it has shown minimal effect as a single agent, however, provided encouraging results in combination with other chemotherapy agents. FDA has granted orphan drug status to bryostatin-1 in combination with paclitaxel for esophageal cancer. Bryostatin-1 has also received orphan drug status for fragile X syndrome. Bryostatin-1 was also investigated in clinical studies for Alzheimer's disease and HIV infection. In a nutshell, the natural as well as synthetic bryostatins have generated a strong hope to emerge as treatment for cancer along with many other diseases.
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Affiliation(s)
- Rinky Raghuvanshi
- Medicinal Chemistry Division, CSIR- Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India.,Academy of Scientific & Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Sandip B Bharate
- Medicinal Chemistry Division, CSIR- Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India.,Academy of Scientific & Innovative Research (AcSIR), Ghaziabad-201002, India
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7
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Tyagi K, Roy A. Evaluating the current status of protein kinase C (PKC)-protein kinase D (PKD) signalling axis as a novel therapeutic target in ovarian cancer. Biochim Biophys Acta Rev Cancer 2020; 1875:188496. [PMID: 33383102 DOI: 10.1016/j.bbcan.2020.188496] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 12/19/2020] [Accepted: 12/19/2020] [Indexed: 12/14/2022]
Abstract
Ovarian cancer, especially high grade serous ovarian cancer is one of the most lethal gynaecological malignancies with high relapse rate and patient death. Notwithstanding development of several targeted treatment and immunotherapeutic approaches, researchers fail to turn ovarian cancer into a manageable disease. Protein kinase C (PKC) and protein kinase D (PKD) are families of evolutionarily conserved serine/threonine kinases that can be activated by a plethora of extracellular stimuli such as hormones, growth factors and G-protein coupled receptor agonists. Recent literature suggests that a signalling cascade initiated by these two protein kinases regulates a battery of cellular and physiological processes involved in tumorigenesis including cell proliferation, migration, invasion and angiogenesis. In an urgent need to discover novel therapeutic interventions against a deadly pathology like ovarian cancer, we have discussed the status quo of PKC/PKD signalling axis in context of this disease. Additionally, apart from discussing the structural properties and activation mechanisms of PKC/PKD, we have provided a comprehensive review of the recent reports on tumor promoting functions of PKC isoforms and discussed the potential of PKC/PKD signalling axis as a novel target in this lethal pathology. Furthermore, in this review, we have discussed the significance of several recent clinical trials and development of small molecule inhibitors that target PKC/PKD signalling axis in ovarian cancer.
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Affiliation(s)
- Komal Tyagi
- Amity Institute of Molecular Medicine and Stem Cell Research, Amity University, Sector-125, Noida, Uttar Pradesh 201303, India
| | - Adhiraj Roy
- Amity Institute of Molecular Medicine and Stem Cell Research, Amity University, Sector-125, Noida, Uttar Pradesh 201303, India.
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8
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Pache L, Marsden MD, Teriete P, Portillo AJ, Heimann D, Kim JT, Soliman MS, Dimapasoc M, Carmona C, Celeridad M, Spivak AM, Planelles V, Cosford ND, Zack JA, Chanda SK. Pharmacological Activation of Non-canonical NF-κB Signaling Activates Latent HIV-1 Reservoirs In Vivo. Cell Rep Med 2020; 1:100037. [PMID: 33205060 PMCID: PMC7659604 DOI: 10.1016/j.xcrm.2020.100037] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 04/01/2020] [Accepted: 05/27/2020] [Indexed: 02/07/2023]
Abstract
"Shock and kill" strategies focus on purging the latent HIV-1 reservoir by treating infected individuals with therapeutics that activate the latent virus and subsequently eliminating infected cells. We have previously reported that induction of non-canonical nuclear factor κB (NF-κB) signaling through a class of small-molecule antagonists known as Smac mimetics can reverse HIV-1 latency. Here, we describe the development of Ciapavir (SBI-0953294), a molecule specifically optimized for HIV-1 latency reversal that was found to be more efficacious as a latency-reversing agent than other Smac mimetics under clinical development for cancer. Critically, this molecule induced activation of HIV-1 reservoirs in vivo in a bone marrow, liver, thymus (BLT) humanized mouse model without mediating systemic T cell activation. This study provides proof of concept for the in vivo efficacy and safety of Ciapavir and indicates that Smac mimetics can constitute a critical component of a safe and efficacious treatment strategy to eliminate the latent HIV-1 reservoir.
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Affiliation(s)
- Lars Pache
- Infectious and Inflammatory Disease Center, Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Matthew D. Marsden
- Division of Hematology and Oncology, Department of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Peter Teriete
- Cell Metabolism and Signaling Networks Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Alex J. Portillo
- Infectious and Inflammatory Disease Center, Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Dominik Heimann
- Cell Metabolism and Signaling Networks Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Jocelyn T. Kim
- Division of Infectious Diseases, Department of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Mohamed S.A. Soliman
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Melanie Dimapasoc
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Camille Carmona
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Maria Celeridad
- Cell Metabolism and Signaling Networks Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Adam M. Spivak
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Vicente Planelles
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Nicholas D.P. Cosford
- Cell Metabolism and Signaling Networks Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Jerome A. Zack
- Division of Hematology and Oncology, Department of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Sumit K. Chanda
- Infectious and Inflammatory Disease Center, Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
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9
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Ciavatta ML, Lefranc F, Vieira LM, Kiss R, Carbone M, van Otterlo WAL, Lopanik NB, Waeschenbach A. The Phylum Bryozoa: From Biology to Biomedical Potential. Mar Drugs 2020; 18:E200. [PMID: 32283669 PMCID: PMC7230173 DOI: 10.3390/md18040200] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/31/2020] [Accepted: 04/06/2020] [Indexed: 01/06/2023] Open
Abstract
Less than one percent of marine natural products characterized since 1963 have been obtained from the phylum Bryozoa which, therefore, still represents a huge reservoir for the discovery of bioactive metabolites with its ~6000 described species. The current review is designed to highlight how bryozoans use sophisticated chemical defenses against their numerous predators and competitors, and which can be harbored for medicinal uses. This review collates all currently available chemoecological data about bryozoans and lists potential applications/benefits for human health. The core of the current review relates to the potential of bryozoan metabolites in human diseases with particular attention to viral, brain, and parasitic diseases. It additionally weighs the pros and cons of total syntheses of some bryozoan metabolites versus the synthesis of non-natural analogues, and explores the hopes put into the development of biotechnological approaches to provide sustainable amounts of bryozoan metabolites without harming the natural environment.
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Affiliation(s)
- Maria Letizia Ciavatta
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Chimica Biomolecolare (ICB), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.L.C.); (M.C.)
| | - Florence Lefranc
- Service de Neurochirurgie, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Leandro M. Vieira
- Departamento de Zoologia, Centro de Biociências, Universidade Federal de Pernambuco, Recife, PE 50670-901, Brazil;
| | - Robert Kiss
- Retired – formerly at the Fonds National de la Recherche Scientifique (FRS-FNRS), 1000 Brussels, Belgium;
| | - Marianna Carbone
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Chimica Biomolecolare (ICB), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.L.C.); (M.C.)
| | - Willem A. L. van Otterlo
- Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa;
| | - Nicole B. Lopanik
- School of Earth and Atmospheric Sciences, School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA;
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Buscail L, Bournet B, Cordelier P. Role of oncogenic KRAS in the diagnosis, prognosis and treatment of pancreatic cancer. Nat Rev Gastroenterol Hepatol 2020; 17:153-168. [PMID: 32005945 DOI: 10.1038/s41575-019-0245-4] [Citation(s) in RCA: 361] [Impact Index Per Article: 90.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/21/2019] [Indexed: 02/08/2023]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is predicted to be the second most common cause of death within the next 10 years. The prognosis for this disease is poor despite diagnostic progress and new chemotherapeutic regimens. The oncogenic KRAS mutation is the major event in pancreatic cancer; it confers permanent activation of the KRAS protein, which acts as a molecular switch to activate various intracellular signalling pathways and transcription factors inducing cell proliferation, migration, transformation and survival. Several laboratory methods have been developed to detect KRAS mutations in biological samples, including digital droplet PCR (which displays high sensitivity). Clinical studies have revealed that a KRAS mutation assay in fine-needle aspiration material combined with cytopathology increases the sensitivity, accuracy and negative predictive value of cytopathology for a positive diagnosis of pancreatic cancer. In addition, the presence of KRAS mutations in serum and plasma (liquid biopsies) correlates with a worse prognosis. The presence of mutated KRAS can also have therapeutic implications, whether at the gene level per se, during its post-translational maturation, interaction with nucleotides and after activation of the various oncogenic signals. Further pharmacokinetic and toxicological studies on new molecules are required, especially small synthetic molecules, before they can be used in the therapeutic arsenal for pancreatic ductal adenocarcinoma.
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Affiliation(s)
- Louis Buscail
- Department of Gastroenterology, University of Toulouse III, Rangueil Hospital, Toulouse, France. .,INSERM UMR 1037, Toulouse Centre for Cancer Research, University of Toulouse III, Toulouse, France.
| | - Barbara Bournet
- Department of Gastroenterology, University of Toulouse III, Rangueil Hospital, Toulouse, France.,INSERM UMR 1037, Toulouse Centre for Cancer Research, University of Toulouse III, Toulouse, France
| | - Pierre Cordelier
- INSERM UMR 1037, Toulouse Centre for Cancer Research, University of Toulouse III, Toulouse, France
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From Seabed to Bedside: A Review on Promising Marine Anticancer Compounds. Biomolecules 2020; 10:biom10020248. [PMID: 32041255 PMCID: PMC7072248 DOI: 10.3390/biom10020248] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/29/2020] [Accepted: 02/04/2020] [Indexed: 02/08/2023] Open
Abstract
The marine environment represents an outstanding source of antitumoral compounds and, at the same time, remains highly unexplored. Organisms living in the sea synthesize a wide variety of chemicals used as defense mechanisms. Interestingly, a large number of these compounds exert excellent antitumoral properties and have been developed as promising anticancer drugs that have later been approved or are currently under validation in clinical trials. However, due to the high need for these compounds, new methodologies ensuring its sustainable supply are required. Also, optimization of marine bioactives is an important step for their success in the clinical setting. Such optimization involves chemical modifications to improve their half-life in circulation, potency and tumor selectivity. In this review, we outline the most promising marine bioactives that have been investigated in cancer models and/or tested in patients as anticancer agents. Moreover, we describe the current state of development of anticancer marine compounds and discuss their therapeutic limitations as well as different strategies used to overcome these limitations. The search for new marine antitumoral agents together with novel identification and chemical engineering approaches open the door for novel, more specific and efficient therapeutic agents for cancer treatment.
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12
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Role of Dendritic Cells in Exposing Latent HIV-1 for the Kill. Viruses 2019; 12:v12010037. [PMID: 31905690 PMCID: PMC7019604 DOI: 10.3390/v12010037] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/19/2019] [Accepted: 12/24/2019] [Indexed: 12/11/2022] Open
Abstract
The development of effective yet nontoxic strategies to target the latent human immunodeficiency virus-1 (HIV-1) reservoir in antiretroviral therapy (ART)-suppressed individuals poses a critical barrier to a functional cure. The ‘kick and kill’ approach to HIV eradication entails proviral reactivation during ART, coupled with generation of cytotoxic T lymphocytes (CTLs) or other immune effectors equipped to eliminate exposed infected cells. Pharmacological latency reversal agents (LRAs) that have produced modest reductions in the latent reservoir ex vivo have not impacted levels of proviral DNA in HIV-infected individuals. An optimal cure strategy incorporates methods that facilitate sufficient antigen exposure on reactivated cells following the induction of proviral gene expression, as well as the elimination of infected targets by either polyfunctional HIV-specific CTLs or other immune-based strategies. Although conventional dendritic cells (DCs) have been used extensively for the purpose of inducing antigen-specific CTL responses in HIV-1 clinical trials, their immunotherapeutic potential as cellular LRAs has been largely ignored. In this review, we discuss the challenges associated with current HIV-1 eradication strategies, as well as the unharnessed potential of ex vivo-programmed DCs for both the ‘kick and kill’ of latent HIV-1.
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13
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Kristoff J, Palma ML, Garcia-Bates TM, Shen C, Sluis-Cremer N, Gupta P, Rinaldo CR, Mailliard RB. Type 1-programmed dendritic cells drive antigen-specific latency reversal and immune elimination of persistent HIV-1. EBioMedicine 2019; 43:295-306. [PMID: 30952614 PMCID: PMC6557749 DOI: 10.1016/j.ebiom.2019.03.077] [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: 01/08/2019] [Revised: 03/25/2019] [Accepted: 03/26/2019] [Indexed: 12/22/2022] Open
Abstract
Background Despite the success of antiretroviral therapy (ART), latent HIV-1 continues to persist in a long-lived population of resting memory CD4+ T cells within those who are infected. Finding a safe and effective means to induce latency reversal (LR) during ART to specifically expose this latent HIV-1 cellular reservoir for immune elimination has been a major barrier to a functional cure. Methods In this study, we test the use of antigen-presenting type 1-polarized, monocyte-derived dendritic cells (MDC1) generated from chronic HIV-1-infected individuals on ART as a means to induce HIV-1 latency reversal in autologous CD4+ T cells harboring replication-competent provirus. We use the same MDC1 for ex-vivo generation of autologous HIV-1 antigen-specific CD8+ cytotoxic T cells (CTL) and test their effector responses against the MDC1-exposed HIV-1- infected CD4+ T cell targets. Findings MDC1 presentation of either HIV-1 or cytomegalovirus (CMV) antigens to CD4+ T cells facilitated HIV-1 LR. This antigen-driven MDC1-mediated LR was sharply diminished with blockade of the CD40L/CD40 ‘helper’ signaling pathway. Importantly, these antigen-presenting MDC1 also activated the expansion of CTL capable of killing the exposed HIV-1-infected targets. Interpretation Inclusion of virus-associated MHC class II ‘helper’ antigens in MDC1-based HIV-1 immunotherapies could serve both as a targeted means to safely unmask antigen-specific CD4+ T cells harboring HIV-1, and to support CTL responses that can effectively target the MDC1-exposed HIV-1 cellular reservoir as a functional cure strategy. Fund This study was supported by the NIH-NAID grants R21-AI131763, U01-AI35041, UM1-AI126603, and T32-AI065380.
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Affiliation(s)
- Jan Kristoff
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Mariana L Palma
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Tatiana M Garcia-Bates
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Chengli Shen
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Nicolas Sluis-Cremer
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Phalguni Gupta
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Charles R Rinaldo
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America; Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America
| | - Robbie B Mailliard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, United States of America.
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14
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Clutton GT, Jones RB. Diverse Impacts of HIV Latency-Reversing Agents on CD8+ T-Cell Function: Implications for HIV Cure. Front Immunol 2018; 9:1452. [PMID: 29988382 PMCID: PMC6023971 DOI: 10.3389/fimmu.2018.01452] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 06/12/2018] [Indexed: 12/20/2022] Open
Abstract
Antiretroviral therapy regimens durably suppress HIV replication, but do not cure infection. This is partially attributable to the persistence of long-lived pools of resting CD4+ T-cells harboring latent replication-competent virus. Substantial clinical and pre-clinical research is currently being directed at purging this viral reservoir by combining pharmacological latency reversal with immune effectors, such as HIV-specific CD8+ T-cells, capable of eliminating reactivated targets-the so-called "shock-and-kill" approach. However, several studies indicate that the latency-reversing agents (LRAs) may affect CD8+ T-cell function. The current review aims to frame recent advances, and ongoing challenges, in implementing "shock-and-kill" strategies from the perspective of effectively harnessing CD8+ T-cells. We review and contextualize findings indicating that LRAs often have unintended impacts on CD8+ T-cell function, both detrimental and beneficial. We identify and attempt to bridge the gap between viral reactivation, as measured by the detection of RNA or protein, and bona fide presentation of viral antigens to CD8+ T-cells. Finally, we highlight factors on the effector (CD8+) and target (CD4+) cell sides that contribute to whether or not infected-cell recognition results in killing/elimination. These perspectives may contribute to an integrated view of "shock-and-kill," with implications for therapeutic development.
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Affiliation(s)
- Genevieve Tyndale Clutton
- Department of Microbiology and Immunology, UNC Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - R. Brad Jones
- Department of Microbiology Immunology and Tropical Medicine, The George Washington University, Washington, DC, United States
- Infectious Disease Division, Weill Cornell Medical College, New York, NY, United States
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15
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El Bairi K, Amrani M, Afqir S. Starvation tactics using natural compounds for advanced cancers: pharmacodynamics, clinical efficacy, and predictive biomarkers. Cancer Med 2018; 7:2221-2246. [PMID: 29732738 PMCID: PMC6010871 DOI: 10.1002/cam4.1467] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/21/2018] [Accepted: 02/28/2018] [Indexed: 02/05/2023] Open
Abstract
The high mortality associated with oncological diseases is mostly due to tumors in advanced stages, and their management is a major challenge in modern oncology. Angiogenesis is a defined hallmark of cancer and predisposes to metastatic invasion and dissemination and is therefore an important druggable target for cancer drug discovery. Recently, because of drug resistance and poor prognosis, new anticancer drugs from natural sources targeting tumor vessels have attracted more attention and have been used in several randomized and controlled clinical trials as therapeutic options. Here, we outline and discuss potential natural compounds as salvage treatment for advanced cancers from recent and ongoing clinical trials and real-world studies. We also discuss predictive biomarkers for patients' selection to optimize the use of these potential anticancer drugs.
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Affiliation(s)
- Khalid El Bairi
- Faculty of Medicine and PharmacyMohamed Ist UniversityOujdaMorocco
| | - Mariam Amrani
- Equipe de Recherche en Virologie et Onco‐biologieFaculty of MedicinePathology DepartmentNational Institute of OncologyUniversité Mohamed VRabatMorocco
| | - Said Afqir
- Department of Medical OncologyMohamed VI University HospitalOujdaMorocco
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16
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Nelson TJ, Sun MK, Lim C, Sen A, Khan T, Chirila FV, Alkon DL. Bryostatin Effects on Cognitive Function and PKCɛ in Alzheimer's Disease Phase IIa and Expanded Access Trials. J Alzheimers Dis 2018; 58:521-535. [PMID: 28482641 PMCID: PMC5438479 DOI: 10.3233/jad-170161] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Bryostatin 1, a potent activator of protein kinase C epsilon (PKCɛ), has been shown to reverse synaptic loss and facilitate synaptic maturation in animal models of Alzheimer’s disease (AD), Fragile X, stroke, and other neurological disorders. In a single-dose (25 μg/m2) randomized double-blind Phase IIa clinical trial, bryostatin levels reached a maximum at 1-2 h after the start of infusion. In close parallel with peak blood levels of bryostatin, an increase of PBMC PKCɛ was measured (p = 0.0185) within 1 h from the onset of infusion. Of 9 patients with a clinical diagnosis of AD, of which 6 received drug and 3 received vehicle within a double-blind protocol, bryostatin increased the Mini-Mental State Examination (MMSE) score by +1.83±0.70 unit at 3 h versus –1.00±1.53 unit for placebo. Bryostatin was well tolerated in these AD patients and no drug-related adverse events were reported. The 25 μg/m2 administered dose was based on prior clinical experience with three Expanded Access advanced AD patients treated with bryostatin, in which return of major functions such as swallowing, vocalization, and word recognition were noted. In one Expanded Access patient trial, elevated PKCɛ levels closely tracked cognitive benefits in the first 24 weeks as measured by MMSE and ADCS-ADL psychometrics. Pre-clinical mouse studies showed effective activation of PKCɛ and increased levels of BDNF and PSD-95. Together, these Phase IIa, Expanded Access, and pre-clinical results provide initial encouragement for bryostatin 1 as a potential treatment for AD.
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Affiliation(s)
- Thomas J Nelson
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,West Virginia University, Morgantown, WV, USA
| | - Miao-Kun Sun
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,West Virginia University, Morgantown, WV, USA
| | - Chol Lim
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,West Virginia University, Morgantown, WV, USA
| | - Abhik Sen
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,West Virginia University, Morgantown, WV, USA
| | - Tapan Khan
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,West Virginia University, Morgantown, WV, USA
| | - Florin V Chirila
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,Neurodiagnostics, LLC, Rockville, MD, USA
| | - Daniel L Alkon
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA.,Neurotrope Biosciences, LLC, New York, NY, USA
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17
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Toll-Like Receptor 7 Agonist GS-9620 Induces HIV Expression and HIV-Specific Immunity in Cells from HIV-Infected Individuals on Suppressive Antiretroviral Therapy. J Virol 2017; 91:JVI.02166-16. [PMID: 28179531 PMCID: PMC5375698 DOI: 10.1128/jvi.02166-16] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 01/20/2017] [Indexed: 02/07/2023] Open
Abstract
Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs. IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is persistently maintained in reservoirs of latently infected cells. Consequently, lifelong therapy is required to maintain viral suppression. Ultimately, new therapies that specifically target and eliminate the latent HIV reservoir are needed. Toll-like receptor agonists are potent enhancers of innate antiviral immunity that can also improve the adaptive immune response. Here, we show that a highly selective TLR7 agonist, GS-9620, activated HIV from peripheral blood mononuclear cells isolated from HIV-infected individuals with suppressed infection. GS-9620 also improved immune effector functions that specifically targeted HIV-infected cells. Previously published studies on the compound in other chronic viral infections show that it can effectively induce immune activation at safe and tolerable clinical doses. Together, the results of these studies suggest that GS-9620 may be useful for treating HIV-infected individuals on suppressive antiretroviral therapy.
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18
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Promising Role of Toll-Like Receptor 8 Agonist in Concert with Prostratin for Activation of Silent HIV. J Virol 2017; 91:JVI.02084-16. [PMID: 27928016 DOI: 10.1128/jvi.02084-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Accepted: 11/29/2016] [Indexed: 01/03/2023] Open
Abstract
The persistence of latently HIV-infected cells in patients under combined antiretroviral treatment (cART) remains the major hurdle for HIV eradication. Thus far, individual compounds have not been sufficiently potent to reactivate latent virus and guarantee its elimination in vivo. Thus, we hypothesized that transcriptional enhancers, in concert with compounds triggering the innate immune system, are more efficient in reversing latency by creating a Th1 supportive milieu that acts against latently HIV-infected cells at various levels. To test our hypothesis, we screened six compounds on a coculture of latently infected cells (J-lat) and monocyte-derived dendritic cells (MDDCs). The protein kinase C (PKC) agonist prostratin, with a Toll-like receptor 8 (TLR8) agonist, resulted in greater reversion of HIV latency than any single compound. This combinatorial approach led to a drastic phenotypic and functional maturation of the MDDCs. Tumor necrosis factor (TNF) and cell-cell interactions were crucial for the greater reversion observed. Similarly, we found a greater potency of the combination of prostratin and TLR8 agonist in reversing HIV latency when applying it to primary cells of HIV-infected patients. Thus, we demonstrate here the synergistic interplay between TLR8-matured MDDCs and compounds acting directly on latently HIV-infected cells, targeting different mechanisms of latency, by triggering various signaling pathways. Moreover, TLR8 triggering may reverse exhaustion of HIV-specific cytotoxic T lymphocytes that might be essential for killing or constraining the latently infected cells. IMPORTANCE Curing HIV is the Holy Grail. The so-called "shock and kill" strategy relies on drug-mediated reversion of HIV latency and the subsequent death of those cells under combined antiretroviral treatment. So far, no compound achieves efficient reversal of latency or eliminates this latent reservoir. The compounds may not target all of the latency mechanisms in all latently infected cells. Moreover, HIV-associated exhaustion of the immune system hinders the efficient elimination of the reactivated cells. In this study, we demonstrated synergistic latency reversion by combining agonists for protein kinase C and Toll-like receptor 8 in a coculture of latently infected cells with myeloid dendritic cells. The drug prostratin stimulates directly the transcriptional machinery of latently infected cells, and the TLR8 agonist acts indirectly by maturing dendritic cells. These findings highlight the importance of the immune system and its activation, in combination with direct-acting compounds, to reverse latency.
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19
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Abstract
OBJECTIVE The protein kinase C (PKC) agonist bryostatin-1 has shown significant ex-vivo potency to revert HIV-1 latency, compared with other latency reversing agents (LRA). The safety of this candidate LRA remains to be proven in treated HIV-1-infected patients. METHODS In this pilot, double-blind phase I clinical-trial (NCT 02269605), we included aviraemic HIV-1-infected patients on triple antiretroviral therapy to evaluate the effects of two different single doses of bryostatin-1 (10 or 20 μg/m) compared with placebo. RESULTS Twelve patients were included, four in each arm. Bryostatin-1 was well tolerated in all participants. Two patients in the 20 μg/m arm developed grade 1 headache and myalgia. No detectable increases of cell-associated unspliced (CA-US) HIV-1-RNA were observed in any study arm, nor differences in HIV-1 mRNA dynamics between arms (P = 0.44). The frequency of samples with low-level viraemia did not differ between arms and low-level viraemia did not correlate with CA-US HIV-1-RNA levels (P = 0.676). No changes were detected on protein kinase C (PKC) activity and in biomarkers of inflammation (sCD14 and interleukin-6) in any study arm. After the single dose of bryostatin-1, plasma concentrations were under detection limits in all the patients in the 10 μg/m arm, and below 50 pg/ml (0.05 nmol/l) in those in the 20 μg/m arm. CONCLUSION Bryostatin-1 was safe at the single doses administered. However, the drug did not show any effect on PKC activity or on the transcription of latent HIV, probably due to low plasma concentrations. This study will inform next trials aimed at assessing higher doses, multiple dosing schedules or combination studies with synergistic drugs.
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20
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BIRC2/cIAP1 Is a Negative Regulator of HIV-1 Transcription and Can Be Targeted by Smac Mimetics to Promote Reversal of Viral Latency. Cell Host Microbe 2016; 18:345-53. [PMID: 26355217 DOI: 10.1016/j.chom.2015.08.009] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 07/22/2015] [Accepted: 08/25/2015] [Indexed: 11/23/2022]
Abstract
Combination antiretroviral therapy (ART) is able to suppress HIV-1 replication to undetectable levels. However, the persistence of latent viral reservoirs allows for a rebound of viral load upon cessation of therapy. Thus, therapeutic strategies to eradicate the viral latent reservoir are critically needed. Employing a targeted RNAi screen, we identified the ubiquitin ligase BIRC2 (cIAP1), a repressor of the noncanonical NF-κB pathway, as a potent negative regulator of LTR-dependent HIV-1 transcription. Depletion of BIRC2 through treatment with small molecule antagonists known as Smac mimetics enhanced HIV-1 transcription, leading to a reversal of latency in a JLat latency model system. Critically, treatment of resting CD4+ T cells isolated from ART-suppressed patients with the histone deacetylase inhibitor (HDACi) panobinostat together with Smac mimetics resulted in synergistic activation of the latent reservoir. These data implicate Smac mimetics as useful agents for shock-and-kill strategies to eliminate the latent HIV reservoir.
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21
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Gomes NGM, Dasari R, Chandra S, Kiss R, Kornienko A. Marine Invertebrate Metabolites with Anticancer Activities: Solutions to the "Supply Problem". Mar Drugs 2016; 14:E98. [PMID: 27213412 PMCID: PMC4882572 DOI: 10.3390/md14050098] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 04/29/2016] [Accepted: 05/05/2016] [Indexed: 02/07/2023] Open
Abstract
Marine invertebrates provide a rich source of metabolites with anticancer activities and several marine-derived agents have been approved for the treatment of cancer. However, the limited supply of promising anticancer metabolites from their natural sources is a major hurdle to their preclinical and clinical development. Thus, the lack of a sustainable large-scale supply has been an important challenge facing chemists and biologists involved in marine-based drug discovery. In the current review we describe the main strategies aimed to overcome the supply problem. These include: marine invertebrate aquaculture, invertebrate and symbiont cell culture, culture-independent strategies, total chemical synthesis, semi-synthesis, and a number of hybrid strategies. We provide examples illustrating the application of these strategies for the supply of marine invertebrate-derived anticancer agents. Finally, we encourage the scientific community to develop scalable methods to obtain selected metabolites, which in the authors' opinion should be pursued due to their most promising anticancer activities.
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Affiliation(s)
- Nelson G M Gomes
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, R. Jorge Viterbo Ferreira No. 228, 4050-313 Porto, Portugal.
| | - Ramesh Dasari
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA.
| | - Sunena Chandra
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA.
| | - Robert Kiss
- Laboratoire de Cancérologie et de Toxicologie Expérimentale, Faculté de Pharmacie, Université Libre de Bruxelles, Campus de la Plaine, CP205/1, Boulevard du Triomphe, 1050 Brussels, Belgium.
| | - Alexander Kornienko
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA.
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22
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Plummer S, Manning T, Baker T, McGreggor T, Patel M, Wylie G, Phillips D. Isolation, analytical measurements, and cell line studies of the iron-bryostatin-1 complex. Bioorg Med Chem Lett 2016; 26:2489-2497. [PMID: 27068183 DOI: 10.1016/j.bmcl.2016.03.099] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 03/27/2016] [Accepted: 03/28/2016] [Indexed: 10/22/2022]
Abstract
Bryostatin-1 is a marine natural product that has demonstrated medicinal activity in pre-clinical and clinical trials for the treatment of cancer, Alzheimer's disease, effects of stroke, and HIV. In this study, iron-bryostatin-1 was obtained using a pharmaceutical aquaculture technique developed by our lab that cultivates marine bacteria for marine natural product extraction. Analytical measurements (1)H and (13)C NMR, mass spectrometry, and flame atomic absorption were utilized to confirm the presence of an iron-bryostatin-1 complex. The iron-bryostatin-1 complex produced was then tested against the National Cancer Institute's 60 cell line panel. Adding iron to bryostatin-1 lowered the anti-cancer efficacy of the compound.
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Affiliation(s)
- Sydney Plummer
- Department of Chemistry, Valdosta State University, Valdosta, GA 31698, United States
| | - Thomas Manning
- Department of Chemistry, Valdosta State University, Valdosta, GA 31698, United States.
| | - Tess Baker
- Department of Chemistry, Valdosta State University, Valdosta, GA 31698, United States
| | - Tysheon McGreggor
- Department of Chemistry, Valdosta State University, Valdosta, GA 31698, United States
| | - Mehulkumar Patel
- Department of Chemistry, Valdosta State University, Valdosta, GA 31698, United States
| | - Greg Wylie
- NMR Facility, Department of Chemistry, Texas A&M, College Station, TX 77843, United States
| | - Dennis Phillips
- PAMS Facility, Department of Chemistry, University of Georgia, Athens, GA 30602, United States
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An In-Depth Comparison of Latency-Reversing Agent Combinations in Various In Vitro and Ex Vivo HIV-1 Latency Models Identified Bryostatin-1+JQ1 and Ingenol-B+JQ1 to Potently Reactivate Viral Gene Expression. PLoS Pathog 2015. [PMID: 26225566 PMCID: PMC4520688 DOI: 10.1371/journal.ppat.1005063] [Citation(s) in RCA: 210] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The persistence of latently infected cells in patients under combinatory antiretroviral therapy (cART) is a major hurdle to HIV-1 eradication. Strategies to purge these reservoirs are needed and activation of viral gene expression in latently infected cells is one promising strategy. Bromodomain and Extraterminal (BET) bromodomain inhibitors (BETi) are compounds able to reactivate latent proviruses in a positive transcription elongation factor b (P-TEFb)-dependent manner. In this study, we tested the reactivation potential of protein kinase C (PKC) agonists (prostratin, bryostatin-1 and ingenol-B), which are known to activate NF-κB signaling pathway as well as P-TEFb, used alone or in combination with P-TEFb-releasing agents (HMBA and BETi (JQ1, I-BET, I-BET151)). Using in vitro HIV-1 post-integration latency model cell lines of T-lymphoid and myeloid lineages, we demonstrated that PKC agonists and P-TEFb-releasing agents alone acted as potent latency-reversing agents (LRAs) and that their combinations led to synergistic activation of HIV-1 expression at the viral mRNA and protein levels. Mechanistically, combined treatments led to higher activations of P-TEFb and NF-κB than the corresponding individual drug treatments. Importantly, we observed in ex vivo cultures of CD8+-depleted PBMCs from 35 cART-treated HIV-1+ aviremic patients that the percentage of reactivated cultures following combinatory bryostatin-1+JQ1 treatment was identical to the percentage observed with anti-CD3+anti-CD28 antibodies positive control stimulation. Remarkably, in ex vivo cultures of resting CD4+ T cells isolated from 15 HIV-1+ cART-treated aviremic patients, the combinations bryostatin-1+JQ1 and ingenol-B+JQ1 released infectious viruses to levels similar to that obtained with the positive control stimulation. The potent effects of these two combination treatments were already detected 24 hours post-stimulation. These results constitute the first demonstration of LRA combinations exhibiting such a potent effect and represent a proof-of-concept for the co-administration of two different types of LRAs as a potential strategy to reduce the size of the latent HIV-1 reservoirs. Persistence of latently infected cells during cART is a major hurdle for HIV-1 eradication. A widely proposed strategy to purge these reservoirs involves the reactivation of latent proviruses. The low levels of active P-TEFb and the cytoplasmic sequestration of NF-κB in resting infected cells largely contribute to maintenance of HIV-1 latency. Therefore, utilization of chemical compounds that target both pathways may lead to more potent effects on HIV-1 reactivation than the effect mediated by the individual drug treatments. In this study, we showed that combined treatments of PKC agonists (prostratin, bryostatin-1 and ing-B) with compounds releasing P-TEFb (JQ1, I-BET, I-BET151 and HMBA) exhibited a synergistic increase in viral reactivation from latency. In-depth comparison of combined treatments in various in vitro cellular models of HIV-1 latency as well as in ex vivo primary cell cultures from cART-treated HIV+ aviremic patients identified bryostatin-1+JQ1 and ing-B+JQ1 to potently reactivate latent HIV-1. The potent effects of these two combinations were detected as early as 24 hours post-treatment. Importantly, bryostatin-1 was used at concentrations below the drug plasma levels achieved by doses used in children with refractory solid tumors. Our mechanistic data established a correlation between potentiated P-TEFb activation and potentiated or synergistic (depending on the HIV-1 latency cellular model used) induction of HIV-1 gene expression observed after the combined versus individual drug treatments. In conclusion, our results establish a proof-of-concept for PKC agonists combined with compounds releasing active P-TEFb as a strategy proposed for a cure or a durable remission of HIV infection.
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Gao Y, Shan N, Zhao C, Wang Y, Xu F, Li J, Yu X, Gao L, Yi Z. LY2109761 enhances cisplatin antitumor activity in ovarian cancer cells. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:4923-4932. [PMID: 26191185 PMCID: PMC4503057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 03/30/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND AND OBJECTIVE Ovarian cancer is among the most lethal of all malignancies in women. While chemotherapy is the preferred treatment modality, chemoresistance severely limits treatment success. Because transforming growth factor-beta (TGF-β) could increase survival of ovarian cancer cells in the presence of cisplatin, we conducted a preclinical study of the antitumor effects of the TGF-β type I (TβRI) and type II (TβRII) kinase inhibitor LY2109761 in combination with cisplatin. METHODS SKOV3, OV-90 and SKOV3(DDP) cells were treated with LY2109761, and/or cisplatin, and cell viability, apoptosis mRNA and protein expression levels were then evaluated. Furthermore, the efficacy of LY2109761 combined with cisplatin was further examined in established xenograft models. RESULTS LY2109761 was sufficient to induce spontaneous apoptosis of ovarian cancer cells. Combination with LY2109761 significantly augmented the cytotoxicity of cisplatin in both parental and cisplatin resistant ovarian cancer cells. LY2109761 significantly increased apoptotic cell death in cisplatin-resistant cells. Combination treatment of LY2109761 and cisplatin showed antiproliferative effects and induced a greater rate of apoptosis than the sum of the single-treatment rates and promoted tumor regression in established parental and cisplatin resistant ovarian cancer xenograft models. CONCLUSIONS Chemotherapeutic approaches using LY2109761 might enhance the treatment benefit of the cisplatin in the treatment of ovarian cancer patients.
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MESH Headings
- Animals
- Antineoplastic Combined Chemotherapy Protocols/pharmacology
- Apoptosis/drug effects
- Carcinoma, Ovarian Epithelial
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Cell Survival/drug effects
- Cisplatin/pharmacology
- Dose-Response Relationship, Drug
- Drug Resistance, Neoplasm
- Female
- Humans
- Mice, Inbred ICR
- Mice, SCID
- Neoplasms, Glandular and Epithelial/drug therapy
- Neoplasms, Glandular and Epithelial/enzymology
- Neoplasms, Glandular and Epithelial/pathology
- Ovarian Neoplasms/drug therapy
- Ovarian Neoplasms/enzymology
- Ovarian Neoplasms/pathology
- Phosphorylation
- Protein Kinase Inhibitors/pharmacology
- Protein Serine-Threonine Kinases/antagonists & inhibitors
- Protein Serine-Threonine Kinases/metabolism
- Pyrazoles/pharmacology
- Pyrroles/pharmacology
- Receptor, Transforming Growth Factor-beta Type I
- Receptor, Transforming Growth Factor-beta Type II
- Receptors, Transforming Growth Factor beta/antagonists & inhibitors
- Receptors, Transforming Growth Factor beta/metabolism
- Signal Transduction/drug effects
- Smad2 Protein/metabolism
- Time Factors
- Transforming Growth Factor beta/metabolism
- Tumor Burden/drug effects
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Yuxiu Gao
- Department of Diagnostic Ultrasound, The Affiliated Hospital of Qingdao UniversityQingdao, China
| | - Ning Shan
- Department of Obstetrics, People’s Hospital of RizhaoRizhao, China
| | - Cheng Zhao
- Department of Diagnostic Ultrasound, The Affiliated Hospital of Qingdao UniversityQingdao, China
| | - Yunhai Wang
- Department of Diagnostic Ultrasound, The Affiliated Hospital of Qingdao UniversityQingdao, China
| | - Fuliang Xu
- Department of Diagnostic Ultrasound, The Affiliated Hospital of Qingdao UniversityQingdao, China
| | - Jiacun Li
- Department of Clinical Laboratory, The Affiliated Hospital of Weifang Medical CollogeWeifang, China
| | - Xiaoqian Yu
- Department of Clinical Laboratory, The Affiliated Hospital of Weifang Medical CollogeWeifang, China
| | - Lifeng Gao
- Department of Clinical Laboratory, The Affiliated Hospital of Weifang Medical CollogeWeifang, China
| | - Zhengjun Yi
- Department of Diagnostic Ultrasound, The Affiliated Hospital of Qingdao UniversityQingdao, China
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25
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A Survey of Marine Natural Compounds and Their Derivatives with Anti-cancer Activity Reported in 2012. Molecules 2015; 20:7097-142. [PMID: 25903364 PMCID: PMC6272635 DOI: 10.3390/molecules20047097] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 04/01/2015] [Accepted: 04/03/2015] [Indexed: 12/15/2022] Open
Abstract
Although considerable effort and progress has been made in the search for new anticancer drugs and treatments in the last several decades, cancer remains a major public health problem and one of the major causes of death worldwide. Many sources, including plants, animals, and minerals, are of interest in cancer research because of the possibility of identifying novel molecular therapeutics. Moreover, structure-activity-relationship (SAR) investigations have become a common way to develop naturally derived or semi-synthetic molecular analogues with improved efficacy and decreased toxicity. In 2012, approximately 138 molecules from marine sources, including isolated compounds and their associated analogues, were shown to be promising anticancer drugs. Among these, 62% are novel compounds. In this report, we review the marine compounds identified in 2012 that may serve as novel anticancer drugs.
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HIV-1 latency: an update of molecular mechanisms and therapeutic strategies. Viruses 2014; 6:1715-58. [PMID: 24736215 PMCID: PMC4014718 DOI: 10.3390/v6041715] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 02/06/2023] Open
Abstract
The major obstacle towards HIV-1 eradication is the life-long persistence of the virus in reservoirs of latently infected cells. In these cells the proviral DNA is integrated in the host’s genome but it does not actively replicate, becoming invisible to the host immune system and unaffected by existing antiviral drugs. Rebound of viremia and recovery of systemic infection that follows interruption of therapy, necessitates life-long treatments with problems of compliance, toxicity, and untenable costs, especially in developing countries where the infection hits worst. Extensive research efforts have led to the proposal and preliminary testing of several anti-latency compounds, however, overall, eradication strategies have had, so far, limited clinical success while posing several risks for patients. This review will briefly summarize the more recent advances in the elucidation of mechanisms that regulates the establishment/maintenance of latency and therapeutic strategies currently under evaluation in order to eradicate HIV persistence.
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Discovery of a small molecule agonist of phosphatidylinositol 3-kinase p110α that reactivates latent HIV-1. PLoS One 2014; 9:e84964. [PMID: 24489654 PMCID: PMC3906007 DOI: 10.1371/journal.pone.0084964] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 11/29/2013] [Indexed: 12/05/2022] Open
Abstract
Combination antiretroviral therapy (cART) can effectively suppress HIV-1 replication, but the latent viral reservoir in resting memory CD4+ T cells is impervious to cART and represents a major barrier to curing HIV-1 infection. Reactivation of latent HIV-1 represents a possible strategy for elimination of this reservoir. In this study we describe the discovery of 1,2,9,10-tetramethoxy-7H-dibenzo[de,g]quinolin-7-one (57704) which reactivates latent HIV-1 in several cell-line models of latency (J89GFP, U1 and ACH-2). 57704 also increased HIV-1 expression in 3 of 4 CD8+-depleted blood mononuclear cell preparations isolated from HIV-1-infected individuals on suppressive cART. In contrast, vorinostat increased HIV-1 expression in only 1 of the 4 donors tested. Importantly, 57704 does not induce global T cell activation. Mechanistic studies revealed that 57704 reactivates latent HIV-1 via the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. 57704 was found to be an agonist of PI3K with specificity to the p110α isoform, but not the p110β, δ or γ isoforms. Taken together, our work suggests that 57704 could serve as a scaffold for the development of more potent activators of latent HIV-1. Furthermore, it highlights the involvement of the PI3K/Akt pathway in the maintenance of HIV-1 latency.
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Cisplatin inhibits hippocampal cell proliferation and alters the expression of apoptotic genes. Neurotox Res 2013; 25:369-80. [PMID: 24277158 DOI: 10.1007/s12640-013-9443-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/11/2013] [Accepted: 11/14/2013] [Indexed: 12/13/2022]
Abstract
The hippocampus, which is critical for memory and spatial navigation, contains a proliferating stem cell niche that is especially vulnerable to antineoplastic drugs such as cisplatin. Although the damaging effects of cisplatin have recently been recognized, the molecular mechanisms underlying its toxic effects on this vital region are largely unknown. Using a focused apoptosis gene array, we analyzed the early cisplatin-induced changes in gene expression in the hippocampus of adult Sprague-Dawley rats and compared the results to those from the inferior colliculus, a non-mitotic auditory region resistant to cisplatin-induced cell death. Two days after a 12 mg/kg dose of cisplatin, significant increases were observed in five proapoptotic genes: Bik, Bid, Bok, Trp53p2, and Card6 and a significant decrease in one antiapoptotic gene Bcl2a1. In contrast, Nol3, an antiapoptotic gene, showed a significant increase in expression. The cisplatin-induced increase in Bid mRNA and decrease in Bcl2a1 mRNA were accompanied by a corresponding increase and decrease of their respective proteins in the hippocampus. In contrast, the cisplatin-induced changes in Bcl2a1, Bid, Bik, and Bok gene expression in the inferior colliculus were strikingly different from those in the hippocampus consistent with the greater susceptibility of the hippocampus to cisplatin toxicity. Cisplatin also significantly reduced immunolabeling of the cell proliferation marker Ki67 in the subgranular zone of the hippocampus 2 days post-treatment. These results indicate that cisplatin-induced hippocampal cell death is mediated by increased expression of proapoptotic and decreased antiapoptotic genes and proteins that likely inhibit hippocampal cell proliferation.
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Nelson TJ, Sen A, Alkon DL, Sun MK. Adduct formation in liquid chromatography-triple quadrupole mass spectrometric measurement of bryostatin 1. J Chromatogr B Analyt Technol Biomed Life Sci 2013; 944:55-62. [PMID: 24291721 DOI: 10.1016/j.jchromb.2013.11.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 11/05/2013] [Accepted: 11/10/2013] [Indexed: 11/25/2022]
Abstract
Bryostatin 1, a potential anti-Alzheimer drug, is effective at subnanomolar concentrations. Measurement is complicated by the formation of low m/z degradation products and the formation of adducts with various cations, which make accurate quantitation difficult. Adduct formation caused the sample matrix or mobile phase to partition bryostatin 1 into products of different mass. Degradation of the 927 [M+Na](+) ion to a 869m/z product was strongly influenced by ionization conditions. We validated a bryostatin 1 assay in biological tissues using capillary column HPLC with nanospray ionization (NSI) in a triple-quadrupole mass spectrometer in selected reaction monitoring (SRM) mode. Adduct formation was controlled by adding 1mM acetic acid and 0.1mM sodium acetate to the HPLC buffer, maximizing the formation of the [M+Na](+) ion. Efficient removal of contaminating cholesterol from the sample during solvent extraction was also critical. The increased sensitivity provided by NSI and capillary-bore columns and the elimination of signal partitioning due to adduct formation and degradation in the ionization source enabled a detection limit of 1×10(-18)mol of bryostatin 1 and a LLOQ of 3×10(-18)mol from 1μl of sample. Bryostatin 1 at low pmol/l concentrations enabled measurement in brain and other tissues without the use of radioactive labels. Despite bryostatin 1's high molecular weight, considerable brain access was observed, with peak brain concentrations exceeding 8% of the peak blood plasma concentrations. Bryostatin 1 readily crosses the blood-brain barrier, reaching peak concentrations of 0.2nM, and specifically activates and translocates brain PKCɛ.
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Affiliation(s)
- Thomas J Nelson
- Blanchette Rockefeller Neurosciences Institute, 8 Medical Center Drive, Morgantown, WV 26505, USA.
| | - Abhik Sen
- Blanchette Rockefeller Neurosciences Institute, 8 Medical Center Drive, Morgantown, WV 26505, USA
| | - Daniel L Alkon
- Blanchette Rockefeller Neurosciences Institute, 8 Medical Center Drive, Morgantown, WV 26505, USA
| | - Miao-Kun Sun
- Blanchette Rockefeller Neurosciences Institute, 8 Medical Center Drive, Morgantown, WV 26505, USA
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Microbial natural products: molecular blueprints for antitumor drugs. J Ind Microbiol Biotechnol 2013; 40:1181-210. [PMID: 23999966 DOI: 10.1007/s10295-013-1331-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 08/07/2013] [Indexed: 12/18/2022]
Abstract
Microbes from two of the three domains of life, the Prokarya, and Eukarya, continue to serve as rich sources of structurally complex chemical scaffolds that have proven to be essential for the development of anticancer therapeutics. This review describes only a handful of exemplary natural products and their derivatives as well as those that have served as elegant blueprints for the development of novel synthetic structures that are either currently in use or in clinical or preclinical trials together with some of their earlier analogs in some cases whose failure to proceed aided in the derivation of later compounds. In every case, a microbe has been either identified as the producer of secondary metabolites or speculated to be involved in the production via symbiotic associations. Finally, rapidly evolving next-generation sequencing technologies have led to the increasing availability of microbial genomes. Relevant examples of genome mining and genetic manipulation are discussed, demonstrating that we have only barely scratched the surface with regards to harnessing the potential of microbes as sources of new pharmaceutical leads/agents or biological probes.
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Sgarbanti M, Battistini A. Therapeutics for HIV-1 reactivation from latency. Curr Opin Virol 2013; 3:394-401. [PMID: 23810462 DOI: 10.1016/j.coviro.2013.06.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/03/2013] [Accepted: 06/04/2013] [Indexed: 10/26/2022]
Abstract
Intensive combined antiretroviral therapy successfully suppresses HIV-1 replication and AIDS disease progression making infection manageable, but it is unable to eradicate the virus that persists in long-lived, drug-insensitive and immune system-insensitive reservoirs thus asking for life-long treatments with problems of compliance, resistance, toxicity and cost. These limitations and recent insights into latency mechanisms have fueled a renewed effort in finding a cure for HIV-1 infection. Proposed eradication strategies involve reactivation of the latent reservoir upon induction of viral transcription followed by the elimination of reactivated virus-producing cells by viral cytopathic effect or host immune response. Several molecules identified by mechanism-directed approaches or in large-scale screenings have been proposed as latency reversing agents. Some of them have already entered clinical testing in humans but with mixed or unsatisfactory results.
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Affiliation(s)
- Marco Sgarbanti
- Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy
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Wang YQ, Miao ZH. Marine-derived angiogenesis inhibitors for cancer therapy. Mar Drugs 2013; 11:903-33. [PMID: 23502698 PMCID: PMC3705379 DOI: 10.3390/md11030903] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 02/25/2013] [Accepted: 03/01/2013] [Indexed: 12/18/2022] Open
Abstract
Angiogenesis inhibitors have been successfully used for cancer therapy in the clinic. Many marine-derived natural products and their analogues have been reported to show antiangiogenic activities. Compared with the drugs in the clinic, these agents display interesting characteristics, including diverse sources, unique chemical structures, special modes of action, and distinct activity and toxicity profiles. This review will first provide an overview of the current marine-derived angiogenesis inhibitors based on their primary targets and/or mechanisms of action. Then, the marine-derived antiangiogenic protein kinase inhibitors will be focused on. And finally, the clinical trials of the marine-derived antiangiogenic agents will be discussed, with special emphasis on their application potentials, problems and possible coping strategies in their future development as anticancer drugs.
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Affiliation(s)
- Ying-Qing Wang
- Division of Antitumor Pharmacology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China.
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Cragg GM, Newman DJ. Natural products: a continuing source of novel drug leads. Biochim Biophys Acta Gen Subj 2013; 1830:3670-95. [PMID: 23428572 DOI: 10.1016/j.bbagen.2013.02.008] [Citation(s) in RCA: 1578] [Impact Index Per Article: 143.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 01/30/2013] [Accepted: 02/05/2013] [Indexed: 12/14/2022]
Abstract
BACKGROUND Nature has been a source of medicinal products for millennia, with many useful drugs developed from plant sources. Following discovery of the penicillins, drug discovery from microbial sources occurred and diving techniques in the 1970s opened the seas. Combinatorial chemistry (late 1980s), shifted the focus of drug discovery efforts from Nature to the laboratory bench. SCOPE OF REVIEW This review traces natural products drug discovery, outlining important drugs from natural sources that revolutionized treatment of serious diseases. It is clear Nature will continue to be a major source of new structural leads, and effective drug development depends on multidisciplinary collaborations. MAJOR CONCLUSIONS The explosion of genetic information led not only to novel screens, but the genetic techniques permitted the implementation of combinatorial biosynthetic technology and genome mining. The knowledge gained has allowed unknown molecules to be identified. These novel bioactive structures can be optimized by using combinatorial chemistry generating new drug candidates for many diseases. GENERAL SIGNIFICANCE The advent of genetic techniques that permitted the isolation / expression of biosynthetic cassettes from microbes may well be the new frontier for natural products lead discovery. It is now apparent that biodiversity may be much greater in those organisms. The numbers of potential species involved in the microbial world are many orders of magnitude greater than those of plants and multi-celled animals. Coupling these numbers to the number of currently unexpressed biosynthetic clusters now identified (>10 per species) the potential of microbial diversity remains essentially untapped.
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Affiliation(s)
- Gordon M Cragg
- Division of Cancer Treatment and Diagnosis, Frederick National Laboratory for Cancer Research, Frederick, MD 21702-1201, USA
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Abstract
Recent advances in antiretroviral therapy (ART) have drastically improved the quality of life for people with HIV infection. However, owing to the persistence of latent HIV in the presence of therapy, patients must remain on therapy indefinitely. Currently, the solution to the HIV pandemic rests on the prevention of new infections and many decades of ART for the steadily expanding number of people infected worldwide. ART is costly, requires ongoing medical care, and can have side effects, thereby preventing its universal availability. Therefore, to escape the ironic burdens of therapy, efforts have begun to develop treatments for latent HIV infection. Current approaches propose either complete eradication of infection or induction of a state of stringent control over viral replication without ART. This review will discuss these strategies in detail and their potential for clinical development.
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