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Nanomedicine approaches for medulloblastoma therapy. JOURNAL OF PHARMACEUTICAL INVESTIGATION 2022. [DOI: 10.1007/s40005-022-00597-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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2
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Rhaman MM, Islam MR, Akash S, Mim M, Noor alam M, Nepovimova E, Valis M, Kuca K, Sharma R. Exploring the role of nanomedicines for the therapeutic approach of central nervous system dysfunction: At a glance. Front Cell Dev Biol 2022; 10:989471. [PMID: 36120565 PMCID: PMC9478743 DOI: 10.3389/fcell.2022.989471] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/08/2022] [Indexed: 12/12/2022] Open
Abstract
In recent decades, research scientists, molecular biologists, and pharmacologists have placed a strong emphasis on cutting-edge nanostructured materials technologies to increase medicine delivery to the central nervous system (CNS). The application of nanoscience for the treatment of neurodegenerative diseases (NDs) such as Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis (MS), Huntington’s disease (HD), brain cancer, and hemorrhage has the potential to transform care. Multiple studies have indicated that nanomaterials can be used to successfully treat CNS disorders in the case of neurodegeneration. Nanomedicine development for the cure of degenerative and inflammatory diseases of the nervous system is critical. Nanoparticles may act as a drug transporter that can precisely target sick brain sub-regions, boosting therapy success. It is important to develop strategies that can penetrate the blood–brain barrier (BBB) and improve the effectiveness of medications. One of the probable tactics is the use of different nanoscale materials. These nano-based pharmaceuticals offer low toxicity, tailored delivery, high stability, and drug loading capacity. They may also increase therapeutic effectiveness. A few examples of the many different kinds and forms of nanomaterials that have been widely employed to treat neurological diseases include quantum dots, dendrimers, metallic nanoparticles, polymeric nanoparticles, carbon nanotubes, liposomes, and micelles. These unique qualities, including sensitivity, selectivity, and ability to traverse the BBB when employed in nano-sized particles, make these nanoparticles useful for imaging studies and treatment of NDs. Multifunctional nanoparticles carrying pharmacological medications serve two purposes: they improve medication distribution while also enabling cell dynamics imaging and pharmacokinetic study. However, because of the potential for wide-ranging clinical implications, safety concerns persist, limiting any potential for translation. The evidence for using nanotechnology to create drug delivery systems that could pass across the BBB and deliver therapeutic chemicals to CNS was examined in this study.
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Affiliation(s)
- Md. Mominur Rhaman
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
- *Correspondence: Md. Mominur Rhaman, ; Rohit Sharma,
| | - Md. Rezaul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Shopnil Akash
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Mobasharah Mim
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Md. Noor alam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czech Republic
| | - Martin Valis
- Department of Neurology, Charles University in Prague, Faculty of Medicine in Hradec Králové and University Hospital, Hradec Králové, Czech Republic
| | - Kamil Kuca
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czech Republic
- Andalusian Research Institute in Data Science and Computational Intelligence (DaSCI), University of Granada, Granada, Spain
| | - Rohit Sharma
- Department of Rasa Shastra and Bhaishajya Kalpana, Faculty of Ayurveda, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
- *Correspondence: Md. Mominur Rhaman, ; Rohit Sharma,
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3
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Pardridge WM. A Historical Review of Brain Drug Delivery. Pharmaceutics 2022; 14:1283. [PMID: 35745855 PMCID: PMC9229021 DOI: 10.3390/pharmaceutics14061283] [Citation(s) in RCA: 63] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/01/2022] [Accepted: 06/07/2022] [Indexed: 12/13/2022] Open
Abstract
The history of brain drug delivery is reviewed beginning with the first demonstration, in 1914, that a drug for syphilis, salvarsan, did not enter the brain, due to the presence of a blood-brain barrier (BBB). Owing to restricted transport across the BBB, FDA-approved drugs for the CNS have been generally limited to lipid-soluble small molecules. Drugs that do not cross the BBB can be re-engineered for transport on endogenous BBB carrier-mediated transport and receptor-mediated transport systems, which were identified during the 1970s-1980s. By the 1990s, a multitude of brain drug delivery technologies emerged, including trans-cranial delivery, CSF delivery, BBB disruption, lipid carriers, prodrugs, stem cells, exosomes, nanoparticles, gene therapy, and biologics. The advantages and limitations of each of these brain drug delivery technologies are critically reviewed.
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Affiliation(s)
- William M Pardridge
- Department of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
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Faouzi A, Roullin VG. Think Big, Start Small: How Nanomedicine Could Alleviate the Burden of Rare CNS Diseases. Pharmaceuticals (Basel) 2021; 14:109. [PMID: 33573213 PMCID: PMC7912386 DOI: 10.3390/ph14020109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/13/2022] Open
Abstract
The complexity and organization of the central nervous system (CNS) is widely modulated by the presence of the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB), which both act as biochemical, dynamic obstacles impeding any type of undesirable exogenous exchanges. The disruption of these barriers is usually associated with the development of neuropathologies which can be the consequence of genetic disorders, local antigenic invasions, or autoimmune diseases. These disorders can take the shape of rare CNS-related diseases (other than Alzheimer's and Parkinson's) which a exhibit relatively low or moderate prevalence and could be part of a potential line of treatments from current nanotargeted therapies. Indeed, one of the most promising therapeutical alternatives in that field comes from the development of nanotechnologies which can be divided between drug delivery systems and diagnostic tools. Unfortunately, the number of studies dedicated to treating these rare diseases using nanotherapeutics is limited, which is mostly due to a lack of interest from industrial pharmaceutical companies. In the present review, we will provide an overview of some of these rare CNS diseases, discuss the physiopathology of these disorders, shed light on how nanotherapies could be of interest as a credible line of treatment, and finally address the major issues which can hinder the development of efficient therapies in that area.
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Affiliation(s)
- Abdelfattah Faouzi
- Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO 63131, USA;
| | - Valérie Gaëlle Roullin
- Laboratoire de Nanotechnologies Pharmaceutiques, Faculté de Pharmacie, Université de Montréal, Montréal, QC H3T 1J4, Canada
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Hanes J, Dobakova E, Majerova P. Brain Drug Delivery: Overcoming the Blood-brain Barrier to Treat Tauopathies. Curr Pharm Des 2020; 26:1448-1465. [PMID: 32178609 DOI: 10.2174/1381612826666200316130128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 02/10/2020] [Indexed: 02/06/2023]
Abstract
Tauopathies are neurodegenerative disorders characterized by the deposition of abnormal tau protein in the brain. The application of potentially effective therapeutics for their successful treatment is hampered by the presence of a naturally occurring brain protection layer called the blood-brain barrier (BBB). BBB represents one of the biggest challenges in the development of therapeutics for central nervous system (CNS) disorders, where sufficient BBB penetration is inevitable. BBB is a heavily restricting barrier regulating the movement of molecules, ions, and cells between the blood and the CNS to secure proper neuronal function and protect the CNS from dangerous substances and processes. Yet, these natural functions possessed by BBB represent a great hurdle for brain drug delivery. This review is concentrated on summarizing the available methods and approaches for effective therapeutics' delivery through the BBB to treat neurodegenerative disorders with a focus on tauopathies. It describes the traditional approaches but also new nanotechnology strategies emerging with advanced medical techniques. Their limitations and benefits are discussed.
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Affiliation(s)
- Jozef Hanes
- Institute of Neuroimmunology, Slovak Academy of Sciences, Centre of Excellence for Alzheimer's Disease and Related Disorders, Dubravska cesta 9, 845 10 Bratislava, Slovakia
| | - Eva Dobakova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Centre of Excellence for Alzheimer's Disease and Related Disorders, Dubravska cesta 9, 845 10 Bratislava, Slovakia
| | - Petra Majerova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Centre of Excellence for Alzheimer's Disease and Related Disorders, Dubravska cesta 9, 845 10 Bratislava, Slovakia
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Karmur BS, Philteos J, Abbasian A, Zacharia BE, Lipsman N, Levin V, Grossman S, Mansouri A. Blood-Brain Barrier Disruption in Neuro-Oncology: Strategies, Failures, and Challenges to Overcome. Front Oncol 2020; 10:563840. [PMID: 33072591 PMCID: PMC7531249 DOI: 10.3389/fonc.2020.563840] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/13/2020] [Indexed: 01/05/2023] Open
Abstract
The blood-brain barrier (BBB) presents a formidable challenge in the development of effective therapeutics in neuro-oncology. This has fueled several decades of efforts to develop strategies for disrupting the BBB, but progress has not been satisfactory. As such, numerous drug- and device-based methods are currently being investigated in humans. Through a focused assessment of completed, active, and pending clinical trials, our first aim in this review is to outline the scientific foundation, successes, and limitations of the BBBD strategies developed to date. Among 35 registered trials relevant to BBBD in neuro-oncology in the ClinicalTrials.gov database, mannitol was the most common drug-based method, followed by RMP-7 and regadenoson. MR-guided focused ultrasound was the most common device-based method, followed by MR-guided laser ablation, ultrasound, and transcranial magnetic stimulation. While most early-phase studies focusing on safety and tolerability have met stated objectives, advanced-phase studies focusing on survival differences and objective tumor response have been limited by heterogeneous populations and tumors, along with a lack of control arms. Based on shared challenges among all methods, our second objective is to discuss strategies for confirmation of BBBD, choice of systemic agent and drug design, alignment of BBBD method with real-world clinical workflow, and consideration of inadvertent toxicity associated with disrupting an evolutionarily-refined barrier. Finally, we conclude with a strategic proposal to approach future studies assessing BBBD.
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Affiliation(s)
- Brij S Karmur
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | | | - Aram Abbasian
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Brad E Zacharia
- Penn State Health Neurosurgery, College of Medicine, Penn State University, Hershey, PA, United States
| | - Nir Lipsman
- Division of Neurosurgery, University of Toronto, Toronto, ON, Canada
| | - Victor Levin
- Department of Neurosurgery, Medical School, University of California, San Francisco, San Francisco, CA, United States
| | - Stuart Grossman
- Department of Oncology, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Alireza Mansouri
- Penn State Health Neurosurgery, College of Medicine, Penn State University, Hershey, PA, United States
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Huang R, Boltze J, Li S. Strategies for Improved Intra-arterial Treatments Targeting Brain Tumors: a Systematic Review. Front Oncol 2020; 10:1443. [PMID: 32983974 PMCID: PMC7479245 DOI: 10.3389/fonc.2020.01443] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 07/08/2020] [Indexed: 12/16/2022] Open
Abstract
Conventional treatments for brain tumors relying on surgery, radiation, and systemic chemotherapy are often associated with high recurrence and poor prognosis. In recent decades, intra-arterial administration of anti-cancer drugs has been considered a suitable alternative drug delivery route to intravenous and oral administration. Intra-arterial administration is believed to offer increasing drug responses by primary and metastatic brain tumors, and to be associated with better median overall survival. By directly injecting therapeutic agents into carotid or vertebral artery, intra-arterial administration rapidly increases intra-tumoral drug concentration but lowers systemic exposure. However, unexpected vascular or neural toxicity has questioned the therapeutic safety of intra-arterial drug administration and limits its widespread clinical application. Therefore, improving targeting and accuracy of intra-arterial administration has become a major research focus. This systematic review categorizes strategies for optimizing intra-arterial administration into five categories: (1) transient blood-brain barrier (BBB)/blood-tumor barrier (BTB) disruption, (2) regional cerebral hypoperfusion for peritumoral hemodynamic changes, (3) superselective endovascular intervention, (4) high-resolution imaging techniques, and (5) others such as cell and gene therapy. We summarize and discuss both preclinical and clinical research, focusing on advantages and disadvantages of different treatment strategies for a variety of cerebral tumor types.
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Affiliation(s)
- Rui Huang
- Department of Neurology, Dalian Municipal Central Hospital Affiliated With Dalian Medical University, Dalian, China
| | - Johannes Boltze
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Shen Li
- Department of Neurology, Dalian Municipal Central Hospital Affiliated With Dalian Medical University, Dalian, China
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A unified in vitro test system for the assessment of tight junction modulators. Eur J Pharm Biopharm 2019; 142:353-363. [DOI: 10.1016/j.ejpb.2019.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 11/23/2022]
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Marceau F, Bawolak MT, Fortin JP, Morissette G, Roy C, Bachelard H, Gera L, Charest-Morin X. Bifunctional ligands of the bradykinin B 2 and B 1 receptors: An exercise in peptide hormone plasticity. Peptides 2018; 105:37-50. [PMID: 29802875 DOI: 10.1016/j.peptides.2018.05.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 05/14/2018] [Accepted: 05/15/2018] [Indexed: 12/24/2022]
Abstract
Kinins are the small and fragile hydrophilic peptides related to bradykinin (BK) and derived from circulating kininogens via the action of kallikreins. Kinins bind to the preformed and widely distributed B2 receptor (B2R) and to the inducible B1 receptor (B1R). B2Rs and B1Rs are related G protein coupled receptors that possess natural agonist ligands of nanomolar affinity (BK and Lys BK for B2Rs, Lys-des-Arg9-BK for B1R). Decades of structure-activity exploration have resulted in the production of peptide analogs that are antagonists, one of which is clinically used (the B2R antagonist icatibant), and also non-peptide ligands for both receptor subtypes. The modification of kinin receptor ligands has made them resistant to extracellular or endosomal peptidases and/or produced bifunctional ligands, defined as agonist or antagonist peptide ligands conjugated with a chemical fluorophore (emitting in the whole spectrum, from the infrared to the ultraviolet), a drug-like moiety, an epitope, an isotope chelator/carrier, a cleavable sequence (thus forming a pro-drug) and even a fused protein. Dual molecular targets for specific modified peptides may be a source of side effects or of medically exploitable benefits. Biotechnological protein ligands for either receptor subtype have been produced: they are enhanced green fluorescent protein or the engineered peroxidase APEX2 fused to an agonist kinin sequence at their C-terminal terminus. Antibodies endowed with pharmacological actions (agonist, antagonist) at B2R have been reported, though not monoclonal antibodies. These findings define classes of alternative ligands of the kinin receptor of potential therapeutic and diagnostic value.
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Affiliation(s)
| | | | | | | | - Caroline Roy
- CHU de Québec - Université Laval, Québec, QC, G1 V 4G2, Canada
| | | | - Lajos Gera
- Department of Biochemistry, University of Colorado Denver, Aurora, CO, 80045, USA
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González-Mariscal L, Raya-Sandino A, González-González L, Hernández-Guzmán C. Relationship between G proteins coupled receptors and tight junctions. Tissue Barriers 2018; 6:e1414015. [PMID: 29420165 DOI: 10.1080/21688370.2017.1414015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Tight junctions (TJs) are sites of cell-cell adhesion, constituted by a cytoplasmic plaque of molecules linked to integral proteins that form a network of strands around epithelial and endothelial cells at the uppermost portion of the lateral membrane. TJs maintain plasma membrane polarity and form channels and barriers that regulate the transit of ions and molecules through the paracellular pathway. This structure that regulates traffic between the external milieu and the organism is affected in numerous pathological conditions and constitutes an important target for therapeutic intervention. Here, we describe how a wide array of G protein-coupled receptors that are activated by diverse stimuli including light, ions, hormones, peptides, lipids, nucleotides and proteases, signal through heterotrimeric G proteins, arrestins and kinases to regulate TJs present in the blood-brain barrier, the blood-retinal barrier, renal tubular cells, keratinocytes, lung and colon, and the slit diaphragm of the glomerulus.
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Affiliation(s)
- Lorenza González-Mariscal
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
| | - Arturo Raya-Sandino
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
| | - Laura González-González
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
| | - Christian Hernández-Guzmán
- a Department of Physiology , Biophysics and Neuroscience, Center for Research and Advanced Studies (Cinvestav) , Mexico City , Mexico
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Ma T, Xue YX. MiRNA-200b Regulates RMP7-Induced Increases in Blood-Tumor Barrier Permeability by Targeting RhoA and ROCKII. Front Mol Neurosci 2016; 9:9. [PMID: 26903801 PMCID: PMC4742559 DOI: 10.3389/fnmol.2016.00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 01/18/2016] [Indexed: 12/20/2022] Open
Abstract
The primary goals of this study were to investigate the potential roles of miR-200b in regulating RMP7-induced increases in blood-tumor barrier (BTB) permeability and some of the possible molecular mechanisms associated with this effect. Microarray analysis revealed 34 significantly deregulated miRNAs including miR-200b in the BTB as induced by RMP7 and 8 significantly up-regulated miRNAs in the BTB by RMP7. RMP7 induced tight junction (TJ) opening of the BTB, thereby increasing BTB permeability. Associated with this effect of RMP7 was a decrease in miR-200b expression within the human cerebral microvascular endothelial cells line hCMEC/D3 (ECs) of the BTB. Overexpression of miR-200b inhibited endothelial leakage and restored normal transendothelial electric resistance values. A simultaneous shift in occludin and claudin-5 distributions from insoluble to soluble fractions were observed to be significantly reduced. In addition, overexpression of miR-200b inhibited the relocation of occludin and claudin-5 from cellular borders into the cytoplasm as well as the production of stress fiber formation in GECs (ECs with U87 glioma cells co-culturing) of the BTB. MiR-200b silencing produced opposite results as that obtained from that of the miR-200b overexpression group. Overexpression of miR-200b was also associated with a down-regulation in RhoA and ROCKII expression, concomitant with a decrease in BTB permeability. Again, results which were opposite to that obtained with the miR-200b silencing group. We further found that miR-200b regulated BTB permeability by directly targeting RhoA and ROCKII. Collectively, these results suggest that miR-200b's contribution to the RMP7-induced increase in BTB permeability was associated with stress fiber formation and TJ disassembly as achieved by directly targeting RhoA and ROCKII.
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Affiliation(s)
- Teng Ma
- Department of Neurobiology, College of Basic Medicine, China Medical UniversityShenyang, China; Institute of Pathology and Pathophysiology, China Medical UniversityShenyang, China
| | - Yi-Xue Xue
- Department of Neurobiology, College of Basic Medicine, China Medical UniversityShenyang, China; Institute of Pathology and Pathophysiology, China Medical UniversityShenyang, China
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Hersh DS, Wadajkar AS, Roberts NB, Perez JG, Connolly NP, Frenkel V, Winkles JA, Woodworth GF, Kim AJ. Evolving Drug Delivery Strategies to Overcome the Blood Brain Barrier. Curr Pharm Des 2016; 22:1177-1193. [PMID: 26685681 PMCID: PMC4900538 DOI: 10.2174/1381612822666151221150733] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 12/18/2015] [Indexed: 01/10/2023]
Abstract
The blood-brain barrier (BBB) poses a unique challenge for drug delivery to the central nervous system (CNS). The BBB consists of a continuous layer of specialized endothelial cells linked together by tight junctions, pericytes, nonfenestrated basal lamina, and astrocytic foot processes. This complex barrier controls and limits the systemic delivery of therapeutics to the CNS. Several innovative strategies have been explored to enhance the transport of therapeutics across the BBB, each with individual advantages and disadvantages. Ongoing advances in delivery approaches that overcome the BBB are enabling more effective therapies for CNS diseases. In this review, we discuss: (1) the physiological properties of the BBB, (2) conventional strategies to enhance paracellular and transcellular transport through the BBB, (3) emerging concepts to overcome the BBB, and (4) alternative CNS drug delivery strategies that bypass the BBB entirely. Based on these exciting advances, we anticipate that in the near future, drug delivery research efforts will lead to more effective therapeutic interventions for diseases of the CNS.
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Affiliation(s)
| | | | | | | | | | | | | | - Graeme F. Woodworth
- Address correspondence to these authors at the Department of Neurosurgery, University of Maryland School of Medicine, 22 South Greene Street, Baltimore, MD 21201; E-mail: , Departments of Neurosurgery and Pharmaceutical Sciences, University of Maryland, Baltimore, 655 W. Baltimore Street, Baltimore, MD 21201;, E-mail:
| | - Anthony J. Kim
- Address correspondence to these authors at the Department of Neurosurgery, University of Maryland School of Medicine, 22 South Greene Street, Baltimore, MD 21201; E-mail: , Departments of Neurosurgery and Pharmaceutical Sciences, University of Maryland, Baltimore, 655 W. Baltimore Street, Baltimore, MD 21201;, E-mail:
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van Tellingen O, Yetkin-Arik B, de Gooijer M, Wesseling P, Wurdinger T, de Vries H. Overcoming the blood–brain tumor barrier for effective glioblastoma treatment. Drug Resist Updat 2015; 19:1-12. [DOI: 10.1016/j.drup.2015.02.002] [Citation(s) in RCA: 438] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/23/2015] [Accepted: 02/25/2015] [Indexed: 12/23/2022]
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Saaber D, Wollenhaupt S, Baumann K, Reichl S. Recent progress in tight junction modulation for improving bioavailability. Expert Opin Drug Discov 2014; 9:367-81. [PMID: 24558958 DOI: 10.1517/17460441.2014.892070] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Currently, there are many novel drugs that belong to class III or IV of the Biopharmaceutics Classification System, showing low bioavailability. Tight junction (TJ) modulation offers an approach to increase bioavailability of pharmaceutical compounds. Furthermore, some diseases are accompanied by disturbed barrier function or TJ dysregulation and thus represent a second application for TJ modulators. AREAS COVERED This review contains a summary of three different TJ modulators: AT1002, PN159 and labradimil. Within this summary, the authors provide a description of their effects on TJs, their adverse effects and their success in clinical trials. Furthermore, the authors present the current understanding of TJ regulation and highlight opportunities to develop new TJ modulators; they also review the problems that might occur. EXPERT OPINION The development of new mechanism-based (MB) TJ modulators is a very promising field of research. MB approaches are expected to have the best future prospects. Further elucidation of signaling pathways and TJ regulation will be necessary for advancing MB TJ modulator research.
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Affiliation(s)
- Daniel Saaber
- Technische Universität Braunschweig, Institut für Pharmazeutische Technologie , Mendelssohnstr. 1, Braunschweig 38106 , Germany
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Translating the therapeutic potential of neurotrophic factors to clinical 'proof of concept': a personal saga achieving a career-long quest. Neurobiol Dis 2012; 48:153-78. [PMID: 22525569 DOI: 10.1016/j.nbd.2012.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 02/29/2012] [Accepted: 04/06/2012] [Indexed: 01/19/2023] Open
Abstract
While the therapeutic potential of neurotrophic factors has been well-recognized for over two decades, attempts to translate that potential to the clinic have been disappointing, largely due to significant delivery obstacles. Similarly, gene therapy (or gene transfer) emerged as a potentially powerful, new therapeutic approach nearly two decades ago and despite its promise, also suffered serious setbacks when applied to the human clinic. As advances continue to be made in both fields, ironically, they may now be poised to complement each other to produce a translational breakthrough. The accumulated data argue that gene transfer provides the 'enabling technology' that can solve the age-old delivery problems that have plagued the translation of neurotrophic factors as treatments for chronic central nervous system diseases. A leading translational program applying gene transfer to deliver a neurotrophic factor to rejuvenate and protect degenerating human neurons is CERE-120 (AAV2-NRTN). To date, over two dozen nonclinical studies and three clinical trials have been completed. A fourth (pivotal) clinical trial has completed all dosing and is currently evaluating safety and efficacy. In total, eighty Parkinson's disease (PD) subjects have thus far been dosed with CERE-120 (some 7 years ago), representing over 250 cumulative patient-years of exposure, with no serious safety issues identified. In a completed sham-surgery, double-blinded controlled trial, though the primary endpoint (the Unified Parkinson's Disease Rating Scale (UDPRS) motor off score measured at 12 months) did not show benefit from CERE-120, several important motor and quality of life measurements did, including the same UPDRS-motor-off score, pre-specified to also be measured at a longer, 18-month post-dosing time point. Importantly, not a single measurement favored the sham control group. This study therefore, provided important, well-controlled evidence establishing 'clinical proof of concept' for gene transfer to the CNS and the first controlled evidence for clinical benefit of a neurotrophic factor in a human neurodegenerative disease. This paper reviews the development of CERE-120, starting historically with the long-standing interest in the therapeutic potential of neurotrophic factors and continuing with selective accounts of past efforts to translate their potential to the clinic, eventually leading to the application of gene transfer and its role as the 'enabling technology'. Because of growing interest in translational R&D, including its practice in industry, the paper is uniquely oriented from the author's personal, quasi-autobiographic perspective and career-long experiences conducting translational research and development, with a focus on various translational neurotrophic factor programs spanning 30+ years in Big Pharma and development-stage biotech companies. It is hoped that by sharing these perspectives, practical insight and information might be provided to others also interested in translational R&D as well as neurotrophic factors and gene therapy, offering readers the opportunity to benefit from some of our successes, while possibly avoiding some of our missteps.
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Monoclonal antibody therapy for malignant glioma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 746:121-41. [PMID: 22639164 DOI: 10.1007/978-1-4614-3146-6_10] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Monoclonal antibody (mAb) therapy is a rapidly evolving treatment immunotherapy modality for malignant gliomas. Many studies have provided evidence that the blood brain barrier-both at baseline and in the context of malignancy-is permissive for mAbs, thus providing a rationale for their use in treating intracranial malignancy. Furthermore, techniques such as convection enhanced delivery (CED) are being implemented to maximize exposure of tumor cells to mAb therapy. The mechanisms and designs of mAbs are widely varying, including unarmed immunoglobulins as well as immunoglobulins conjugated to radioisotopes, biological toxins, boronated dendrimers and immunoliposomes. The very structure of the immunoglobulin molecule has also been manipulated to generate a diverse armamentarium including single-chain Fv, bispecific T-cell engagers and chimeric antigen receptors. The targeted neutralization capacity of mAbs has been employed to modulate the immunologic milieu in hopes of optimizing other immunotherapy platforms. Many clinical trials have evaluated these mAb strategies to treat malignant gliomas, and the implementation of mAb therapy seems imminent and optimistic.
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Kuo YC, Lee CL. Methylmethacrylate-sulfopropylmethacrylate nanoparticles with surface RMP-7 for targeting delivery of antiretroviral drugs across the blood-brain barrier. Colloids Surf B Biointerfaces 2011; 90:75-82. [PMID: 22024400 DOI: 10.1016/j.colsurfb.2011.09.048] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Accepted: 09/29/2011] [Indexed: 10/16/2022]
Abstract
This study investigates the capability of methylmethacrylate-sulfopropylmethacrylate (MMA-SPM) nanoparticles (NPs) with grafted RMP-7 (RMP-7/MMA-SPM NPs) to deliver stavudine (D4T), delavirdine (DLV), and saquinavir (SQV) across the blood-brain barrier (BBB). The permeability coefficients of the three drugs across the BBB were evaluated by a co-culture model containing human brain-microvascular endothelial cells and human astrocytes. An increase in the concentration of ammonium persulfate (APS), the polymerization initiator, enhanced the particle size of drug-loaded RMP-7/MMA-SPM NPs. When the concentration of APS was 0.6%, the average particle diameter was smaller than 50 nm. These spherical drug carriers were uniform in size and displayed a dominant topography of discrete hillocks and deep pits in deposited film. Smaller RMP-7/MMA-SPM NPs yielded a larger drug loading efficiency. The order of drug in the loading efficiency and in the particle uptake was, respectively, D4T>DLV>SQV and D4T>SQV>DLV. Endocytosis of RMP-7/MMA-SPM NPs and tight junction mediation can improve the permeability of D4T, DLV, and SQV across the BBB.
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Affiliation(s)
- Yung-Chih Kuo
- Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan, ROC.
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18
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Zhang Z, Xue Y, Liu Y, Shang X. Additive effect of low-frequency ultrasound and endothelial monocyte-activating polypeptide II on blood-tumor barrier in rats with brain glioma. Neurosci Lett 2010; 481:21-5. [PMID: 20600613 DOI: 10.1016/j.neulet.2010.06.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Revised: 06/11/2010] [Accepted: 06/12/2010] [Indexed: 11/25/2022]
Abstract
Brain glioma is a malignant tumor which needs surgery followed by chemotherapy. Low-frequency ultrasound (LFU) and Optison could open blood-tumor barrier (BTB) selectively and noninvasively and thus increase the permeability of BTB. Endothelial monocyte-activating polypeptide II (EMAP-II) induces cytoskeletal remodeling in endothelial cells. In this study, we asked whether LFU, Optison, and/or EMAP-II used in combination have additive effects on increasing the permeability of BTB by tight junction (TJ)-associated protein-dependent manner and thus help understand the possible mechanisms for TJ-based drug delivery to the central nervous system through BTB. Evans Blue assay was used to measure the permeability of BTB in rat model of C6 glioma. The mRNA and protein levels of TJ-associated proteins, claudin-5, occludin, and ZO-1, were determined. Results showed that Evans blue content significantly increased and the mRNA and protein levels of claudin-5, occludin, and ZO-1 significantly reduced after the treatment in groups treated with EMAP-II and LFU combined with or without Optison (LFU+EMAP-II and LFU+Optison+EMAP-II groups) and in the group treated with LFU and Optison (LFU+Optison group). In conclusion, LFU and EMAP-II used in combination have additive effects on increasing the permeability of BTB and remodeling of TJ-associated proteins.
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Affiliation(s)
- Zhen Zhang
- Department of Ultrasound, Affiliated First Hospital, China Medical University, Shenyang, Liaoning 110001, PR China
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19
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Stukel JM, Caplan MR. Targeted drug delivery for treatment and imaging of glioblastoma multiforme. Expert Opin Drug Deliv 2009; 6:705-18. [PMID: 19538036 DOI: 10.1517/17425240902988470] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Glioblastoma multiforme is a grade IV astrocytic tumor with a very high mortality rate. Although current treatment often includes surgical resection, this rarely removes all primary tumor cells, so is usually followed by radiation and/or chemotherapy. Remaining migratory tumor cells invade surrounding healthy tissue and contribute to secondary and tertiary tumor recurrence; therefore, despite significant research into glioma removal and treatment, prognosis remains poor. A variety of treatment modalities have been investigated to deliver drug to these cells, including systemic, diffusive and convection-enhanced delivery (CED). As systemic delivery is limited by molecules larger than approximately 500 Da being unable to cross the blood-brain barrier (BBB), therapeutic concentrations are difficult to attain; thus, localized delivery options relying on diffusion and CED have been used to circumvent the BBB. Although CED enables delivery to a greater volume of tissue than diffusive delivery alone, limitations still exist, requiring that these delivery strategies be improved. This review enumerates the strengths and weaknesses of these currently used strategies and details how predictive mathematical modeling can be used to aid investigators in optimizing these delivery modalities for clinical application.
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Affiliation(s)
- Jill M Stukel
- Arizona State University, Center for Interventional Biomaterials, Harrington Department of Bioengineering, Tempe, AZ 85287, USA
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20
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Zhang Z, Xia C, Xue Y, Liu Y. Synergistic effect of low-frequency ultrasound and low-dose bradykinin on increasing permeability of the blood-tumor barrier by opening tight junction. J Neurosci Res 2009; 87:2282-9. [PMID: 19326437 DOI: 10.1002/jnr.22061] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Low-frequency ultrasound (LFU) and bradykinin (BK) have been shown separately to increase the permeability of the blood-tumor barrier (BTB) in the rat model of C6 glioma. This study examined the hypothesis that the combination of LFU and low-dose BK has a synergistic effect on increasing the permeability of BTB and explored the possible underlying mechanism including the involvement of tight junction (TJ). The rats were divided into six groups: control group, LFU group, BK group, 2/3LFU + 1/2BK group, 5/6LFU + 2/3BK group, and LFU + BK group. The BTB permeability was assessed by Evans blue extravasation. The mRNA and protein expressions of TJ-related proteins ZO-1, occludin, and claudin-5 were determined by reverse transcriptase-polymerase chain reaction, immunohistochemistry, immunolocalization, and Western blot test. BTB permeability increased in all the experimental groups, accompanied by opening of local TJ of the BTB, observed by transmission electron microscopy, and decreased mRNA and protein expressions of ZO-1, occludin, and claudin-5. In addition, there was a further increase in BTB permeability and a further reduction in the expressions of TJ-related proteins in 5/6LFU + 2/3BK and LFU + BK groups, compared with LFU or BK group. These results indicate that LFU and low-dose BK applied in combination act in a synergistic manner to increase BTB permeability. The down-regulation of TJ-related proteins ZO-1, occludin, and claudin-5 may be one of the underlying mechanisms of the increase in BTB permeability induced by LFU and BK.
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Affiliation(s)
- Zhen Zhang
- Department of Neurobiology, Basic Medical Science College of China Medical University, Shenyang, PR China
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21
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Hirschberg H, Zhang MJ, Gach HM, Uzal FA, Peng Q, Sun CH, Chighvinadze D, Madsen SJ. Targeted delivery of bleomycin to the brain using photo-chemical internalization of Clostridium perfringens epsilon prototoxin. J Neurooncol 2009; 95:317-329. [PMID: 19506813 PMCID: PMC2773371 DOI: 10.1007/s11060-009-9930-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Accepted: 05/24/2009] [Indexed: 01/09/2023]
Abstract
Cells infiltrating into normal brain from malignant brain tumors are protected by the blood brain barrier (BBB) which prevents the delivery and limits the effects of anti-tumor agents. We have evaluated the ability of photochemical internalization (PCI) to limit the effects of an agent known to broadly open the BBB to a target region of the brain. The PCI-based relocation and activation of macromolecules into the cell cytosol has the advantage of minimal side effects since the effect is localized to the area exposed to light, allowing the access of chemotherapeutic agents only to these regions. Non tumor bearing inbred Fisher rats were treated with photosesitizer, and a nontoxic intraperitoneal dose of Clostridium perfringens epsilon prototoxin (ETXp) followed by light exposure. Post-contrast T1 MRI scans were used to monitor the degree BBB disruption. F98 tumor cells were implanted into the brains of other animals that were subsequently treated 24 h later with ETXp-PCI BBB opening followed by the i.p. administration of bleomycin (BLM). PCI delivery of ETXp at low fluence levels demonstrated significant MRI enhancement. No effect on the BBB was observed if photosesitizer and light was given in the absence ETXp. The survival of animals implanted with F98 tumor cells was significantly extended following ETXp-PCI BBB opening and BLM therapy compared to controls. PCI delivered ETXp was effective in opening the BBB in a limited region of the brain. ETXp-PCI mediated BBB opening clearly increased the efficacy of BLM therapy.
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Affiliation(s)
- Henry Hirschberg
- Beckman Laser Institute, University of California, Irvine, CA, USA.
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV, USA.
| | - Michelle J Zhang
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV, USA
| | | | - Francisco A Uzal
- School of Veterinary Medicine, University of California, Davis, San Bernardino, CA, USA
| | - Qian Peng
- Department of Pathology, The Norwegian Radium Hospital, Oslo, Norway
| | - Chung-Ho Sun
- Beckman Laser Institute, University of California, Irvine, CA, USA
| | - David Chighvinadze
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV, USA
| | - Steen J Madsen
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV, USA
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Mayer CR, Geis NA, Katus HA, Bekeredjian R. Ultrasound targeted microbubble destruction for drug and gene delivery. Expert Opin Drug Deliv 2009; 5:1121-38. [PMID: 18817517 DOI: 10.1517/17425247.5.10.1121] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Gas-filled microbubbles have been used as ultrasound contrast agents for some decades. More recently, such microbubbles have evolved as experimental tools for organ- and tissue-specific drug and gene delivery. When sonified with ultrasound near their resonance frequency, microbubbles oscillate. With higher ultrasound energies, oscillation amplitudes increase, leading to microbubble destruction. This phenomenon can be used to deliver a substance into a target organ, if microbubbles are co-administered loaded with drugs or gene therapy vectors before i.v. injection. OBJECTIVE This review focuses on different experimental applications of microbubbles as tools for drug and gene delivery. Different organ systems and different classes of bioactive substances that have been used in previous studies will be discussed. METHODS All the available literature was reviewed to highlight the potential of this non-invasive, organ-specific delivery system. CONCLUSION Ultrasound targeted microbubble destruction has been used in various organ systems and in tumours to successfully deliver drugs, proteins, gene therapy vectors and gene silencing constructs. Many proof of principle studies have demonstrated its potential as a non-invasive delivery tool. However, too few large animal studies and studies with therapeutic aims have been performed to see a clinical application of this technique in the near future. Nevertheless, there is great hope that preclinical large animal studies will confirm the successful results already obtained in small animals.
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Affiliation(s)
- Christian R Mayer
- University of Heidelberg, Department of Internal Medicine III, Im Neuenheimer Feld 410, 69120 Heidelberg,Germany
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Bartus RT, Snodgrass P, Dean RL, Kim BS, Black K, Emerich DF. Use of CereportTM (RMP-7) to Increase Delivery of Carboplatin to Gliomas: Insight and Parameters for Intracarotid Infusion Via a Single-Lumen Cannula. Drug Deliv 2008. [DOI: 10.1080/107175499267110] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
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Black KL, Yin D, Konda BM, Wang X, Hu J, Ko MK, Bayan JA, Sacapano MR, Espinoza AJ, Ong JM, Irvin D, Shu Y. Different effects of KCa and KATP agonists on brain tumor permeability between syngeneic and allogeneic rat models. Brain Res 2008; 1227:198-206. [PMID: 18602898 DOI: 10.1016/j.brainres.2008.06.046] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 06/07/2008] [Accepted: 06/10/2008] [Indexed: 11/17/2022]
Abstract
The blood-brain tumor barrier (BTB) significantly limits delivery of effective concentrations of chemotherapeutic drugs to brain tumors. Previous studies suggest that BTB permeability may be modulated via alteration in the activity of potassium channels. In this study, we studied the relationship of BTB permeability increase mediated by potassium channel agonists to channel expression in two rat brain tumor models. Intravenous infusion of KCO912 (K(ATP) agonist), minoxidil sulfate (K(ATP) agonist) or NS1619 (K(Ca) agonist) increased tumor permeability more in the 9L allogeneic brain tumor model than in the syngeneic brain tumor model. Consistently, expression of both K(ATP) and K(Ca) channels in 9L tumors was increased to a significantly greater extent in Wistar rats (allogeneic) as compared to Fischer rats (syngeneic). Furthermore, as a preliminary effort to understand clinical implication of potassium channels in brain tumor treatment, we determined the expression of K(ATP) in surgical specimens. K(ATP) mRNA was detected in glioblastoma multiforme (GBM) from nineteen patients examined, with a wide range of expression levels. Interestingly, in paired GBM tissues from seven patients before and after vaccination therapy, increased levels of K(ATP) were detected in five patients after vaccination that had positive response to chemotherapy after vaccination. The present study indicates that the effects of potassium channel agonists on BTB permeability are different between syngeneic and allogeneic models which have different expression levels of potassium channels. The expression of potassium channels in brain tumors is variable, which may be associated with different tumor permeability to therapeutic agents among patients.
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Affiliation(s)
- Keith L Black
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, 8631 West Third Street, Suite 800 E., Los Angeles, California 90048, USA.
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25
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Dwibhashyam VSNM, Nagappa AN. Strategies for enhanced drug delivery to the central nervous system. Indian J Pharm Sci 2008; 70:145-53. [PMID: 20046703 PMCID: PMC2792490 DOI: 10.4103/0250-474x.41446] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 02/17/2008] [Accepted: 02/23/2008] [Indexed: 11/29/2022] Open
Abstract
Treating central nervous system diseases is very challenging because of the presence of a variety of formidable obstacles that impede drug delivery. Physiological barriers like the blood-brain barrier and blood-cerebrospinal fluid barrier as well as various efflux transporter proteins make the entry of drugs into the central nervous system very difficult. The present review provides a brief account of the blood brain barrier, the P-glycoprotein efflux and various strategies for enhancing drug delivery to the central nervous system.
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Affiliation(s)
- V. S. N. M. Dwibhashyam
- Pharmacy Practice Department, 4th Floor, Shirdi Sai Baba Cancer Hospital, Manipal-576 104, India
| | - A. N. Nagappa
- TherDose Pharma (P) Ltd., Plot No: 30-32, Survey No. 400, Prasanth Nagar, IE, Hyderabad-500 072, India
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26
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de Vries NA, Beijnen JH, Boogerd W, van Tellingen O. Blood-brain barrier and chemotherapeutic treatment of brain tumors. Expert Rev Neurother 2006; 6:1199-209. [PMID: 16893347 DOI: 10.1586/14737175.6.8.1199] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The blood-brain barrier (BBB) is of pivotal importance to maintain homeostasis of the CNS, as it closely regulates the composition of the interstitial fluid in the brain. Unfortunately, malignancies that grow within the CNS may evade chemotherapeutic drugs using the same barrier, making this disease refractory to most chemotherapy regimens. This review will outline the impact of the BBB in brain cancer and discuss the efforts that have been made to enhance the drug exposure of brain tumors. Although this review will focus on the role of the BBB in primary brain cancer (malignant glioma), its impact on brain metastases will also be briefly discussed.
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Affiliation(s)
- Nienke A de Vries
- The Netherlands Cancer Institute, Department of Clinical Chemistry, Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
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Pulkkanen KJ, Yla-Herttuala S. Gene therapy for malignant glioma: current clinical status. Mol Ther 2006; 12:585-98. [PMID: 16095972 DOI: 10.1016/j.ymthe.2005.07.357] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2005] [Revised: 07/06/2005] [Accepted: 07/06/2005] [Indexed: 12/24/2022] Open
Abstract
Glioblastoma is an aggressive brain tumor with a dismal prognosis. Gene therapy may offer a new option for the treatment of these patients. Several gene therapy approaches have shown anti-tumor efficiency in experimental studies, and the first clinical trials for the treatment of malignant glioma were conducted in the 1990s. HSV-tk gene therapy has been the pioneering and most commonly used approach, but oncolytic conditionally replicating adenoviruses and herpes simplex virus mutant vectors, p53, interleukins, interferons, and antisense oligonucleotides have also been used. During the past few years, adenoviruses have become the most popular gene transfer vectors, and some recent randomized, controlled trials have shown significant anti-tumor efficacy in clinical use. However, efficient gene delivery into the brain still presents a major problem, and there is a lack of definitive phase III trials, which would avoid potential problems associated with a small number of patients, inadvertent patient selection, and overinterpretation of results based on a few long-time survivors. For clinical efficacy, median survival is one of the most rigorous endpoints. It is used here to evaluate the usefulness of various treatment approaches and current clinical status of gene therapy for malignant glioma.
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Affiliation(s)
- Kalevi J Pulkkanen
- Department of Molecular Medicine, AI Virtanen Institute, University of Kuopio, Finland
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28
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Zhao Y, Xue Y, Liu Y, Fu W, Jiang N, An P, Wang P, Yang Z, Wang Y. Study of correlation between expression of bradykinin B2 receptor and pathological grade in human gliomas. Br J Neurosurg 2006; 19:322-6. [PMID: 16455538 DOI: 10.1080/02688690500305555] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In clinical practice there is a difference in response of the blood-tumour barrier (BTB) permeability induced by bradykinin in brain tumours with the same pathology. The variability in response of tumours to bradykinin is likely to be related to the expression level of bradykinin B(2) receptor. This study used fresh human glioma samples to determine the expression level of bradykinin B(2) receptor on gliomas with different pathological grades. The grade of tumour was classified using the WHO classification. To determine the bradykinin B(2) receptor expression level in gliomas, Immunohistochemistry and Western blot methods were used. In 24 cases of gliomas there were eight cases of WHO I glioma, eight cases of WHO II glioma and eight cases of WHO III glioma. Both Western blot and immunohistochemistry showed bradykinin B(2) receptors localized on tumour cells, whilst brain cells at the edge of the glioma hardly expressed B(2) receptor. There were significant differences of bradykinin B(2) receptor expression level among different pathological grades of glioma. The expression of B(2) receptor in the three grades of glioma was in the order of WHO I < WHO II < WHO III. Determination of bradykinin B(2) receptor expression level in human glioma may be useful in screening glioma patients to predict whether they will be suitable for opening of the blood - tumour barrier with bradykinin or its analogue.
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Affiliation(s)
- Yisong Zhao
- Department of Neurobiology, China Medical University, Shenyang, Liaoming Province, Peoples Republic of China
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29
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Warren K, Jakacki R, Widemann B, Aikin A, Libucha M, Packer R, Vezina G, Reaman G, Shaw D, Krailo M, Osborne C, Cehelsky J, Caldwell D, Stanwood J, Steinberg SM, Balis FM. Phase II trial of intravenous lobradimil and carboplatin in childhood brain tumors: a report from the Children’s Oncology Group. Cancer Chemother Pharmacol 2006; 58:343-7. [PMID: 16408203 DOI: 10.1007/s00280-005-0172-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Accepted: 12/12/2005] [Indexed: 12/01/2022]
Abstract
BACKGROUND [corrected] Lobradimil is a synthetic bradykinin analog that rapidly and transiently increases the permeability of the blood-brain barrier (BBB). The combination of lobradimil and carboplatin was studied in pediatric patients with primary brain tumors in a phase II trial, the primary endpoints of which were to estimate the response rate and time to disease progression. PATIENTS AND METHODS Patients were stratified by histology into five cohorts: brainstem glioma, high-grade glioma, low-grade glioma, medullobastoma/primitive neuroectodermal tumor (PNET), and ependymoma. Patients received carboplatin adaptively dosed to achieve a target AUC of 3.5 mg min/ml per day (7 mg.min/ml/cycle) intravenously over 15 min on 2 consecutive days and lobradimil 600 ng/kg ideal body weight/day on 2 consecutive days each 28 day cycle. RESULTS Forty-one patients, age 2-19 years, were enrolled; 38 patients, including 1 patient ultimately determined to have atypical neurocytoma, were evaluable for response. No objective responses were observed in the brainstem glioma (n=12) and high-grade glioma (n = 9) cohorts, although two patients with high-grade glioma had prolonged disease stabilization (>6 months). The study was closed for commercial reasons prior to achieving the accrual goals for the ependymoma (n = 8), medulloblastoma/PNET (n = 6) and low-grade glioma (n = 2) cohorts, although responses were observed in 1 patient with PNET and 2 patients with ependymoma. CONCLUSION The combination of lobradimil and carboplatin was inactive in childhood high-grade gliomas and brainstem gliomas.
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Affiliation(s)
- K Warren
- National Cancer Institute/Neuro-Oncology Branch, Bethesda, MD 20892-8200, USA.
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Packer RJ, Krailo M, Mehta M, Warren K, Allen J, Jakacki R, Villablanca JG, Chiba A, Reaman G. A Phase I study of concurrent RMP-7 and carboplatin with radiation therapy for children with newly diagnosed brainstem gliomas. Cancer 2005; 104:1968-74. [PMID: 16177987 DOI: 10.1002/cncr.21403] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Ninety percent of children with diffuse, intrinsic brainstem tumors will die within 18 months of diagnosis. Radiotherapy is of transient benefit to these children, and a potential way to improve its efficacy is to add radiosensitizers. Carboplatin is antineoplastic and radiosensitizing; however, its delivery to the primary tumor site is problematic. RMP-7 is a bradykinin analog that causes selective permeability of the blood-brain-tumor interface. The objective of this Phase I study was to determine the toxicity and feasibility of delivering RMP-7 and carboplatin for 5 successive days during radiotherapy to children with newly diagnosed, diffuse, intrinsic brainstem gliomas. METHODS RMP-7 was given prior to the end of carboplatin infusion. Local radiotherapy, in dose fractions of 180 centigrays (cGy) per day (to a total dose of 5940 cGy), was given within 4 hours of completion of drug delivery. Duration of treatment was escalated in a stepwise, weekly fashion in cohorts of 3 patients, until there was treatment-limiting toxicity or until radiotherapy was completed. Thirteen patients were treated, and their median age was 7 years (age range, 3-12 yrs). RESULTS One child died early during treatment of progressive disease and was not assessable for toxicity. Treatment for 3 weeks, 4 weeks, and 5 weeks was tolerated well, with mild flushing, tachycardia, nausea, emesis, dizziness, and abdominal pain. One of 3 children treated at the full duration of therapy (33 doses over 7 weeks) developed dose-limiting hepatotoxicity and neutropenia. The estimated median survival was 328 days, and 1 patient remained free of disease progression for > 400 days after the initiation of treatment. CONCLUSIONS The results of this study confirmed the feasibility of giving RMP-7 and carboplatin daily during radiotherapy to children with brainstem tumors.
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Affiliation(s)
- Roger J Packer
- Center for Neuroscience and Behavioral Medicine, Division of Neurology, Children's National Medical Center, Washington, DC 20010, USA.
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31
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Menon D, Karyekar CS, Fasano A, Lu R, Eddington ND. Enhancement of brain distribution of anticancer agents using ΔG, the 12kDa active fragment of ZOT. Int J Pharm 2005; 306:122-31. [PMID: 16274945 DOI: 10.1016/j.ijpharm.2005.09.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2005] [Revised: 08/16/2005] [Accepted: 09/13/2005] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The objective of this study was to evaluate the ability of DeltaG, the 12 kDa active fragment of ZOT, to increase the brain distribution of MTX and paclitaxel, two commonly used anticancer agents with poor distribution into the brain. METHODS As part of dose estimation of DeltaG, [14C]-sucrose (40 microCi/kg), a hydrophilic paracellular marker, was co-administered with DeltaG (0, 400 and 800 microg/kg) with and without protease inhibitors to male Sprague-Dawley rats (n=3 per group) via an intracarotid cannula. MTX (50 mg/kg) and [3H]-paclitaxel (120 microCi/kg) were co-administered with the effective doses of DeltaG determined from the above study via the intracarotid cannula. Animals were euthanized by carbon dioxide asphyxiation at the specified time periods and brain and plasma samples were analyzed for the respective drug. RESULTS The brain distribution of [14C]-sucrose was significantly enhanced at both doses of DeltaG. A fold enhancement in the B/P ratios of 1.88 and 2.68 was observed at the 400 and 800 microg/kg doses respectively, when the protein was protected from metabolic degradation with PIs. DeltaG significantly increased the brain distribution of MTX at each of the doses administered, with over a seven-fold increase at the 600 microg/kg dose. [3H]-paclitaxel brain AUC(0-60 min) was significantly higher in the presence of DeltaG (800 microg/kg with PIs) with a 2.5-fold enhancement in brain exposure. CONCLUSIONS DeltaG significantly enhances the brain distribution of MTX (hydrophilic) and paclitaxel (lipophilic) and has the potential to be further developed as adjunct therapy to increase delivery of poorly permeable chemotherapeutic and other CNS targeted compounds.
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Affiliation(s)
- Divya Menon
- Pharmacokinetics Biopharmaceutics Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, HSF II 543, Baltimore, MD 21201-6808, USA
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Mainio A, Hakko H, Niemelä A, Koivukangas J, Räsänen P. Depression and functional outcome in patients with brain tumors: a population-based 1-year follow-up study. J Neurosurg 2005; 103:841-7. [PMID: 16304988 DOI: 10.3171/jns.2005.103.5.0841] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object. The authors analyzed changes in depression and contemporary functional states by using valid tools in a population-based study sample during a 1-year follow-up period.
Methods. The study population consisted of 77 patients with a solitary primary brain tumor treated surgically at the Oulu Clinic for Neurosurgery. Each patient's depressive status, according to the Beck Depression Inventory (BDI), and functional outcome, based on the Karnofsky Performance Scale (KPS), were evaluated before the tumor was surgically treated as well as 3 months and 1 year after surgery. Before surgery 27 patients (35%) had BDI scores indicating the presence of depression. These scores were significantly higher in patients with a history of depression (p = 0.017) and in those with a lower functional outcome (p = 0.015). In the entire study sample the severity of depression decreased statistically significantly (p = 0.031) at 3 months postsurgery. A lower functional status (KPS score ≤ 70) in patients was significantly associated with high depression scores at the 3-month (p = 0.000) and 1-year (p = 0.005) assessments. The decrease in the level of depression was significant in patients with an anterior tumor (p = 0.049) and those with a pituitary adenoma (p = 0.019).
Conclusions. Affective disorders among patients with brain tumors must be considered immediately after surgery, especially in persons with a depression history and in those with a coincident physical disability.
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Affiliation(s)
- Arja Mainio
- Departments of Psychiatry and Neurosurgery, Oulu University Hospital, Oulu, Finland.
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Packer RJ, Krailo M, Mehta M, Warren K, Allen J, Jakacki R, Villablanca JG, Chiba A, Reaman G. Phase 1 study of concurrent RMP-7 and carboplatin with radiotherapy for children with newly diagnosed brainstem gliomas. Cancer 2005; 104:1281-7. [PMID: 16078267 DOI: 10.1002/cncr.21301] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Ninety percent of children with diffuse intrinsic brainstem tumors will die within 18 months of diagnosis. Radiotherapy is of transient benefit, and one way to potentially improve its efficacy is to add radiosensitizers. Carboplatin is antineoplastic and radiosensitizing. However, delivery to the primary tumor site is problematic. RMP-7 is a bradykinin analog that causes selective permeability of the blood-brain-tumor interface. The goal of the current Phase I study was to determine the toxicity and feasibility of delivering RMP-7 and carboplatin for 5 successive days during radiotherapy. METHODS RMP-7 was given before the end of carboplatin infusion. Local radiotherapy (5940 centigrays) was given within 4 hours of completion of drug delivery. Duration of treatment was escalated in a stepwise, weekly fashion, in cohorts of 3, until there was treatment-limiting toxicity or until radiotherapy was completed. Thirteen patients were treated, whose median age was 7 years (range, 3-14 yrs). RESULTS One child died early in treatment of progressive disease and was not assessable for toxicity. Treatment for 3, 4, or 5 weeks was tolerated well, with mild flushing, tachycardia, nausea, emesis, dizziness, and abdominal pain. Of 3 children treated at the full duration of therapy (33 doses over 7 wks), 1 developed dose-limiting hepatotoxicity and neutropenia. The estimated median survival period was 328 days, and 1 patient remained disease progression free > 400 days from initiation of treatment. CONCLUSIONS The results of the current study confirmed the feasibility of giving RMP-7 and carboplatin daily during radiotherapy.
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Affiliation(s)
- Roger J Packer
- Division of Neurology, Children's National Medical Center, Washington, DC 20010, USA.
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Kirmani JF, Janjua N, Al Kawi A, Ahmed S, Khatri I, Ebrahimi A, Divani AA, Qureshi AI. Therapeutic advances in interventional neurology. NeuroRx 2005; 2:304-23. [PMID: 15897952 PMCID: PMC1064993 DOI: 10.1602/neurorx.2.2.304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Rapid advances in the field of interventional neurology and the development of minimally invasive techniques have resulted in a great expansion of potential therapeutic applications. We discuss therapeutic interventional neurology as applied in clinical practice in one of the two possible ways: 1) embolization leading to occlusion of blood vessels; and 2) revascularization leading to reopening of blood vessels. These procedures can be applied to a broad range of cerebrovascular diseases. In the first section of this review, we will explore the evolution of these interventions to occlude aneurysms, arteriovenous malformations, neurovascular tumors, and injuries. In the second section, revascularization in acute ischemic stroke, stenosis, and dural venous thrombosis will be discussed.
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Affiliation(s)
- Jawad F Kirmani
- Zeenat Qureshi Stroke Research Center, Department of Neurology and Neurosciences, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA.
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Pan W, Kastin AJ. Why study transport of peptides and proteins at the neurovascular interface. ACTA ACUST UNITED AC 2004; 46:32-43. [PMID: 15297153 DOI: 10.1016/j.brainresrev.2004.04.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2004] [Indexed: 01/17/2023]
Abstract
The blood-brain barrier (BBB) is an immense neurovascular interface. In neurodegenerative, ischemic, and traumatic disorders of the central nervous system (CNS), the BBB may hinder the delivery of many therapeutic peptides and proteins to the brain and spinal cord. Fortunately, the mistaken dogma that peptides and proteins do not cross the BBB has been corrected during the past two decades by the accumulating evidence that peptides and proteins in the periphery exert potent effects in the CNS. Not only can peptides and proteins serve as carriers for selective therapeutic agents, but they themselves may directly cross the BBB after delivery into the bloodstream. Their passage may be mediated by simple diffusion or specific transport, both of which can be affected by interactions in the blood compartment (outside the BBB) and within the endothelial cells (at the BBB level). Although the majority of current delivery strategies focuses on modification of the molecule to be delivered, understanding the mechanisms of transport will eventually facilitate regulation of the BBB directly. We review the different aspects of interactions and discuss recent advances in the cell biology of peptide/protein transport across the BBB. Better understanding of the nature and regulation of the transport systems at the BBB will provide a new direction to enhance the interactions of peripheral peptides and proteins with the CNS.
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Affiliation(s)
- Weihong Pan
- Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, USA.
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Kemper EM, Boogerd W, Thuis I, Beijnen JH, van Tellingen O. Modulation of the blood–brain barrier in oncology: therapeutic opportunities for the treatment of brain tumours? Cancer Treat Rev 2004; 30:415-23. [PMID: 15245774 DOI: 10.1016/j.ctrv.2004.04.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Systemically administered chemotherapy is not very effective in the treatment of primary or metastatic brain tumours. An important reason for this low efficacy is insufficient drug delivery to the tumour site due to the presence of the blood-brain barrier (BBB). In this review, we give an overview of strategies that were tested to bypass the BBB or to increase its permeability for anticancer drugs. Local drug administration through intracerebral implants offers only little benefit to patients with brain tumours, probably due to the limited diffusion of the drugs in brain tissue. Temporary disruption of the BBB can be achieved with intracarotid infusions of hypertonic mannitol. This method has been used with some success; however, toxic side effects and the high complexity of the surgical procedure limit its usefulness. More recently, the use of the bradykinin agonist cereport was shown to be useful in preclinical studies, but unfortunately clinical studies did not show improved efficacy. Since P-glycoprotein in the BBB restricts the brain entry of many anticancer drugs, inhibition of this drug transporter may be an option for improved drug delivery to brain tumours. Pre-clinical studies have shown the feasibility to enhance the penetration of paclitaxel into the brain by co-administration with a potent P-glycoprotein inhibitor and further clinical research is warranted.
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Affiliation(s)
- E Marleen Kemper
- Department of Clinical Chemistry, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Huis, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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Hastings RH, Folkesson HG, Matthay MA. Mechanisms of alveolar protein clearance in the intact lung. Am J Physiol Lung Cell Mol Physiol 2004; 286:L679-89. [PMID: 15003932 DOI: 10.1152/ajplung.00205.2003] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Transport of protein across the alveolar epithelial barrier is a critical process in recovery from pulmonary edema and is also important in maintaining the alveolar milieu in the normal healthy lung. Various mechanisms have been proposed for clearing alveolar protein, including transport by the mucociliary escalator, intra-alveolar degradation, or phagocytosis by macrophages. However, the most likely processes are endocytosis across the alveolar epithelium, known as transcytosis, or paracellular diffusion through the epithelial barrier. This article focuses on protein transport studies that evaluate these two potential mechanisms in whole lung or animal preparations. When protein concentrations in the air spaces are low, e.g., albumin concentrations <0.5 g/100 ml, protein transport demonstrates saturation kinetics, temperature dependence indicating high energy requirements, and sensitivity to pharmacological agents that affect endocytosis. At higher concentrations, the protein clearance rate is proportional to protein concentration without signs of saturation, inversely related to protein size, and insensitive to endocytosis inhibition. Temperature dependence suggests a passive process. Based on these findings, alveolar albumin clearance occurs by receptor-mediated transcytosis at low protein concentrations but proceeds by passive paracellular mechanisms at higher concentrations. Because protein concentrations in pulmonary edema fluid are high, albumin concentrations of 5 g/100 ml or more, clearance of alveolar protein occurs by paracellular pathways in the setting of pulmonary edema. Transcytosis may be important in regulating the alveolar milieu under nonpathological circumstances. Alveolar degradation may become important in long-term protein clearance, clearance of insoluble proteins, or under pathological conditions such as immune reactions or acute lung injury.
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Affiliation(s)
- Randolph H Hastings
- VA Medical Center (125 3350 La Jolla Village D., San Diego, CA 92161-5085, USA.
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Abstract
Cerebrovascular diseases are an important cause of morbidity and mortality worldwide. Endovascular treatment has emerged as a minimally invasive approach to treat cerebrovascular diseases and possibly intracranial neoplasms. Practice patterns for selection of patients for endovascular treatment are continuously being modified on the basis of new information derived from clinical studies. In this review, I discuss the various endovascular treatments for diseases such as ischaemic stroke, carotid and intracranial stenosis, intracranial aneurysms, arteriovenous malformations, malignant gliomas, and meningiomas.
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Affiliation(s)
- Adnan I Qureshi
- Cerebrovascular Diseases Program, Department of Neurology and Neurosciences, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103-2425, USA.
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Abstract
Retrovirus (RV) has been one of the earliest recombinant vectors to be investigated in the context of cancer gene therapy. Experiments in cell culture and in animal brain tumor models have demonstrated the feasibility of RV mediated gene transduction and killing of glioma cells by toxicity generating transgenes. Phase I and II clinical studies in patients with recurrent malignant glioma have shown a favorable safety profile and some efficacy of RV mediated gene therapy. On the other hand, a prospective randomized phase III clinical study of RV gene therapy in primary malignant glioma failed to demonstrate significant extension of the progression-free or overall survival times in RV treated patients. The failure of this RV gene therapy study may be due to the low tumor cell transduction rate observed in vivo. The biological effects of the treatment may also heavily depend on the choice of transgene/prodrug system and on the vector delivery methods. Retrovirus clinical trials in malignant glioma have nevertheless produced a substantial amount of data and have contributed toward the identification of serious shortcomings of the non-replicating virus vector gene therapy strategy. Novel types of therapeutic virus vector systems are currently being designed and new clinical protocols are being created based on the lessons learned from the RV gene therapy trials in patients with malignant brain tumors.
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Affiliation(s)
- Nikolai G Rainov
- Department of Neurological Science, University of Liverpool, Liverpool, UK.
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Weyerbrock A, Walbridge S, Pluta RM, Saavedra JE, Keefer LK, Oldfield EH. Selective opening of the blood-tumor barrier by a nitric oxide donor and long-term survival in rats with C6 gliomas. J Neurosurg 2003; 99:728-37. [PMID: 14567609 DOI: 10.3171/jns.2003.99.4.0728] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The response of brain tumors to systemic chemotherapy is limited by the blood-tumor barrier (BTB). Nitric oxide (NO) has been implicated in the regulation of vascular permeability and blood flow. The authors evaluated the effects of exogenous NO, which was released from a short-acting NO donor (Proli/NO), and those of NO metabolites on the capillary permeability of tumors and normal brain tissue by using quantitative autoradiography in a C6 glioma model in rats. METHODS The Proli/NO was infused at a wide dose range (10(-2) to 10(-12) M) either intravenously or into the internal carotid artery (ICA) and demonstrated substantial tumor-selective increases in blood-brain barrier (BBB) permeability in response to various-sized tracers ([14C]aminoisobutyric acid, [14C]sucrose, [14C]dextran). Internal carotid artery or intravenous administration of sodium nitrite had a comparable effect on BTB permeability. The NO effect on microvascular permeability could be obtained without causing hemodynamic side effects. The effect of NO on the efficacy of carboplatin chemotherapy was investigated in intracerebral C6 gliomas. Simultaneous intravenous infusions of Proli/NO (10(-6) M) and carboplatin (20 mg/kg) led to long-term survival in 40% of rats harboring intracerebral C6 gliomas compared with control animals receiving ICA or intravenous infusions of carboplatin, Proli/NO, or vehicle alone. No residual tumor was demonstrated on histological or magnetic resonance imaging studies performed in rats treated with Proli/NO and carboplatin, and no toxicity was observed. CONCLUSIONS This new approach demonstrated the in vivo efficacy and safety of NO and nitrite in enhancing the delivery of systemically delivered radiolabeled tracers and carboplatin into rat gliomas. The NO-induced tumor-selective BBB disruption and intravenous carboplatin chemotherapy may be more efficacious than current chemotherapy strategies against brain tumors.
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Affiliation(s)
- Astrid Weyerbrock
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA
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Rainov NG, Kramm CM. Recombinant retrovirus vectors for treatment of malignant brain tumors. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2003; 55:185-203. [PMID: 12968537 DOI: 10.1016/s0074-7742(03)01008-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Affiliation(s)
- Nikolai G Rainov
- Department of Neurological Science, University of Liverpool, Walton Centre for Neurology and Neurosurgery NHS Trust, Liverpool L9 7LJ, United Kingdom
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Erdlenbruch B, Schinkhof C, Kugler W, Heinemann DEH, Herms J, Eibl H, Lakomek M. Intracarotid administration of short-chain alkylglycerols for increased delivery of methotrexate to the rat brain. Br J Pharmacol 2003; 139:685-94. [PMID: 12812991 PMCID: PMC1573898 DOI: 10.1038/sj.bjp.0705302] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1 The intracarotid administration of alkylglycerols has been reported previously by us to be a novel strategy for increased delivery of various chemotherapeutic drugs to the normal brain and brain tumors in rats. 2 Effectiveness and structure-activity relations of the most promising pentyl- and hexylglycerol derivatives have been elucidated in vivo by analyzing the transfer of methotrexate (MTX) across the blood-brain barrier (BBB) in normal rats. The effects were compared with BBB disruption using hypertonic mannitol or intracarotid infusion of bradykinin. Furthermore, toxicity of the alkylglycerols has been studied in long-term experiments. 3 Apart from 1-O-pentyldiglycerol, all alkylglycerols induced a concentration-dependent increase in MTX delivery to the brain varying from 1.1 to more than 300-fold compared to intra-arterial MTX alone. Enhanced barrier permeability rapidly approached baseline values within 5 and 120 min at the latest. Chemical structure, concentration, time schedule of injections and combination of different alkylglycerols were identified as instruments suited to regulate the MTX accumulation within a wide range. Mannitol 1.4 M resulted in very high MTX levels in the brain as observed using the highest concentrations of alkylglycerols. Intracarotid infusion of bradykinin had only a minor effect on the BBB. Using 1-O-pentylglycerol or 2-O-hexyldiglycerol, both cell culture experiments and long-term in vivo analyses including clinical, laboratory and histopathological evaluations revealed no signs of toxicity. 4 In summary, intracarotid short-chain alkylglycerols constitute a very effective and low toxic strategy for transient opening of the BBB to overcome the limited access of cytotoxic drugs to the brain.
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Affiliation(s)
- Bernhard Erdlenbruch
- Universitätskinderklinik Göttingen, Robert-Koch-Str. 40, D-37075 Göttingen, Germany.
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Borlongan CV, Emerich DF. Facilitation of drug entry into the CNS via transient permeation of blood brain barrier: laboratory and preliminary clinical evidence from bradykinin receptor agonist, Cereport. Brain Res Bull 2003; 60:297-306. [PMID: 12754091 DOI: 10.1016/s0361-9230(03)00043-1] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
One novel approach of transporting drugs into the central nervous system (CNS) involves the activation of receptors on the endothelial cells comprising the blood brain barrier (BBB). Recently the selective B(2) bradykinin receptor agonist, Cereport (also called RMP-7), has been shown to transiently increase permeability of the BBB. Although initially developed to increase the permeability of the vasculature feeding glioma, recent studies have demonstrated that Cereport also increases the delivery of pharmacological agents across the normal (i.e. nontumor) BBB. In this review paper, we discuss evidence of enhanced CNS delivery of carboplatin, loperamide, and cyclosporin-A, which are accompanied by enhanced chemotherapeutic, analgesic and neuroprotective effects, respectively. These observations suggest feasibility of Cereport as an adjunct therapy to pharmacological treatments that require drug availability in the CNS to exert therapeutic efficacy. Because many potential drugs for CNS disorders normally do not cross the BBB, Cereport-induced transient permeation of BBB stands as an efficacious strategy for enhancing pharmacotherapy.
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Affiliation(s)
- C V Borlongan
- Department of Neurology, Medical College of Georgia, BI-3080, 1120 15th Street, Augusta, GA 30912-3200, USA.
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Abstract
PURPOSE Brain tumors were the first human malignancy to be targeted by therapeutic transfer of nucleic acids into somatic cells, a process also known as gene therapy. Malignant brain tumor cells in the adult brain have some unique biologic features, such as high mitotic activity on an essentially postmitotic background and virtually no tumor spread outside of the central nervous system. Brain tumors seem therefore to offer major advantages in the design of tumor-selective gene therapy strategies, and the role of gene therapy in malignant glioma has been investigated since the late 1980s, initially in numerous laboratory studies and later on in clinical trials. DESIGN Retrovirus has been one of the earliest recombinant virus vectors used in brain tumors. Experiments in cell culture and in animal models have demonstrated the feasibility of retrovirus-mediated transduction and subsequent killing of glioma cells by toxic transgenes. Phase I and II clinical studies in patients with recurrent malignant glioma have shown a favorable safety profile and some efficacy of retrovirus-mediated gene therapy. However, the only prospective, randomized, phase III clinical study of retrovirus gene therapy in primary malignant glioma failed to demonstrate significant extension of progression-free or overall survival. Adenovirus- and herpes simplex virus type 1-based vectors have been actively investigated along with retrovirus, but their clinical use is still limited, mostly because of safety concerns. To increase efficacy, novel generations of therapeutic adenovirus and herpes simplex virus type 1 rely more on genetically engineered and tumor-selective lytic properties and less on the actual transfer of therapeutic genes. CONCLUSIONS The failure of most clinical gene therapy protocols to produce a significant and unequivocal benefitto brain tumor patients seems to be mainly due to the low tumor cell transduction rates observed in vivo, but it may also depend on the respective physical delivery strategy of the vector. Standard radiologic criteria for assessing the efficacy of clinical treatments may also not be fully applicable to the specific metabolic changes and blood-brain barrier permeability phenomena caused in brain tumors by virus-mediated gene therapy. Clinical trials in malignant glioma have nevertheless produced a substantial amount of data and have contributed to the continuous improvement of vector systems, delivery methods, and clinical protocols.
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Affiliation(s)
- Nikolai G Rainov
- Department of Neurological Science, University of Liverpool, Liverpool L9 7LJ, UK.
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Karyekar CS, Fasano A, Raje S, Lu R, Dowling TC, Eddington ND. Zonula occludens toxin increases the permeability of molecular weight markers and chemotherapeutic agents across the bovine brain microvessel endothelial cells. J Pharm Sci 2003; 92:414-23. [PMID: 12532391 DOI: 10.1002/jps.10310] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The purpose of this study was to examine the ability of Zonula occludens toxin (Zot) to reversibly open tight junctions in bovine brain microvessel endothelial cells (BBMECs) to enhance drug delivery via the paracellular pathway. Transport across BBMEC monolayers was examined for molecular weight markers and chemotherapeutic agents ([(14)C]sucrose, [(14)C]inulin, [(3)H]propranolol, [(3)H]doxorubicin, and [(14)C]paclitaxel) with Zot (0.0-4.0 microg/mL). TEER of monolayers was measured to assess effect and reversibility of Zot. Cell viability of BBMEC in the presence of Zot was assessed by trypan blue exclusion staining. Apparent permeability (P(app)), enhancement ratio (R), and percent increase in transport determined were statistically compared by ANOVA. A significant increase (p < 0.05) in P(app) was observed for the transport of [(14)C]sucrose, [(14)C]inulin, [(3)H]doxorubicin, and [(14)C]paclitaxel at a 4.0 microg/mL concentration of Zot. A significant concentration-dependent decrease in TEER was observed on treatment with Zot with rapid reversal to baseline after removal. Zot (4 micro/ml) was found to be nontoxic to the BBMECs after 2 hours incubation. In conclusion, Zot increased paracellular transport across the BBMEC in a reversible, concentration-dependent manner. Modulation of paracellular transport with Zot may be used to increase the brain permeability of potent central nervous system-active drugs, including anticancer agents.
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Affiliation(s)
- Chetan S Karyekar
- Pharmacokinetics Biopharmaceutics Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 100 Penn Street, Baltimore, Maryland 21201, USA
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Hashizume K, Black KL. Increased endothelial vesicular transport correlates with increased blood-tumor barrier permeability induced by bradykinin and leukotriene C4. J Neuropathol Exp Neurol 2002; 61:725-35. [PMID: 12152787 DOI: 10.1093/jnen/61.8.725] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Bradykinin and leukotriene C4 (LTC4) have been shown to increase molecular transport across the blood-tumor barrier (BTB). The aim of this study was to quantitatively assess whether an increase in vesicular transport or opening of tight junctions was responsible for this increase in permeability. Wistar rats bearing RG2 or C6 gliomas were infused with bradykinin or LTC4 through the right carotid artery for 15 min and then perfused to achieve fixation. Prepared specimens were observed using transmission electron microscopy. Infusion of either bradykinin or LTC4 resulted in significantly increased vesicular density in capillary endothelial cells of the BTB but not in normal brain capillaries. The opening of tight junctions, assessed by determining a cleft index, was found to be greater in tumor capillaries compared to normal controls. However, neither bradykinin nor LTC4 produce variations in the cleft index. A significant accumulation of horseradish peroxidase was seen in the intercellular peri-capillary spaces and in endothelial transport vesicles after infusion of bradykinin, demonstrating that the formation of vesicles was associated with macromolecular transcytosis. These findings suggest that pinocytotic vesicular transport is the primary means by which luminal to abluminal transport occurs in response to vasomodulation with bradykinin or LTC4.
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Affiliation(s)
- Kazuhiro Hashizume
- Maxine Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California, USA
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Ningaraj NS, Rao M, Hashizume K, Asotra K, Black KL. Regulation of blood-brain tumor barrier permeability by calcium-activated potassium channels. J Pharmacol Exp Ther 2002; 301:838-51. [PMID: 12023511 DOI: 10.1124/jpet.301.3.838] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The blood-brain tumor barrier (BTB) limits the delivery of therapeutic drugs to brain tumors. We demonstrate in a rat brain tumor (RG2) model an enhanced drug delivery to brain tumor following intracarotid infusion of bradykinin (BK), nitric oxide (NO) donors, or agonists of soluble guanylate cyclase (sGC) and calcium-dependent potassium (K(Ca)) channels. We modulated K(Ca) channels by specific agonists and agents that produce NO and cGMP in situ to obtain sustained enhancement of selective drug delivery to brain tumors. Intracarotid infusion of BK or 1,3-dihydro-1-[2-hydroxy-5-(trifluoromethyl)phenyl]-5-(trifluoromethyl)-2H-benzimidazol-2-one (NS-1619) significantly enhanced BTB permeability (K(i)) to [(14)C]alpha-aminoisobutyric acid in the brain tumor area but not in normal brain tissue. The K(i) increase achieved by BK, NS-1619, NO donors, or the sGC activator 3-(5'-hydroxymethyl-2'furyl)-1-benzylindazole (YC-1) was significantly attenuated when coinfused with a K(Ca) channel antagonist, iberiotoxin. Immunoblot and immunolocalization studies demonstrate overexpression of K(Ca) channels in tumor cells and capillaries compared with normal brain. The potentiometric assays demonstrate the functional activity of K(Ca) channels in rat brain endothelial and glioma cells. Additionally, we show that BK and NS-1619 significantly increased the density of transport vesicles in the cytoplasm of brain tumor capillary endothelia and tumor cells. The cleft indices and cleft area indices in rat tumor capillaries were significantly higher than in normal brain capillaries, and BK infusion did not alter these indices. These data demonstrate that the cellular mechanism for K(Ca) channel-mediated BTB permeability increase is due to accelerated formation of pinocytotic vesicles, which can transport drugs across BTB. We conclude that K(Ca) channels serve as a convergence point in the biochemical regulation of BTB permeability.
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Affiliation(s)
- Nagendra S Ningaraj
- Maxine Dunitz Neurosurgical Institute, Division of Cardiology, Cedars-Sinai Medical Center, 8631 West Third Street, Los Angeles, CA 90048, USA
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Wellisch DK, Kaleita TA, Freeman D, Cloughesy T, Goldman J. Predicting major depression in brain tumor patients. Psychooncology 2002; 11:230-8. [PMID: 12112483 DOI: 10.1002/pon.562] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Very few studies have been performed utilizing DSM criteria to diagnose major depressive disorder (MDD) in adult brain tumor patients. This study aimed to diagnose MDD in this population using DSM-IV criteria.Eighty-nine adult brain tumor patients were examined in an ambulatory neuro-oncology clinic setting using a structured psychiatric interview which followed current DSM-IV diagnostic criteria for MDD. This sample was interviewed and evaluated on a one-time basis. The patients were referred for evaluation on a consecutive basis. Multiple regression was used to model critical independent variables to predict MDD.Twenty-eight percent of the sample (N=89) were found to have major depressive disorder using DSM-IV criteria. Key predictors of MDD included frontal region of tumor location (p=0.001), combined sadness and lack of motivation symptoms (p=0.0001), and family psychiatric history (p=0.006). The multiple regression models account for 37% of variance in predicting MDD (R(2)=0.37).A substantially higher incidence of MDD was found in this sample of adult brain tumor patients compared with other adult, ambulatory cancer patients previously evaluated with DSM criteria. The incidence of MDD was about triple that found in other published studies using DSM criteria.
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Affiliation(s)
- David K Wellisch
- Department of Psychiatry, UCLA School of Medicine, Los Angeles, Calif, USA
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Britz GW, Ghatan S, Spence AM, Berger MS. Intracarotid RMP-7 enhanced indocyanine green staining of tumors in a rat glioma model. J Neurooncol 2002; 56:227-32. [PMID: 12061728 DOI: 10.1023/a:1015035213228] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The extent of resection in patients with primary brain tumors may affect the quality of life, time to tumor progression, and survival. Currently, the extent of resection during surgery is guided by the visual appearance and consistency of tumor, frozen sections of the margins, intraoperative ultrasound, and frameless navigational systems and intraoperative imaging modalities. A new method that enhances the visualization of an infiltrating tumor and its margins may further aid in obtaining a more complete resection. A study was thus undertaken to assess the staining of brain tumors using Indocyanine green (ICG), a water-soluble emerald green tricarbocynanine dye concomitantly with RMP-7, a bradykinin analog, that selectively increases vascular permeability in brain tumors. METHODS A syngeneic ethyl-nitrosourea-induced F-344 rat cell line (36B-10) was stereotactically implanted into 25 rats, and allowed to mature for 15-18 days. Intracarotid administration of 0.75 ml of RMP-7 at a standard dose of 0.4 microg/ml over 15 min was then infused. Varying doses of ICG (range, 0-60 mg/kg) were then injected 15 min after the RMP-7 infusion ended. The animals were sacrificed 15 min after the ICG infusion was completed, and the brains examined macroscopically and microscopically for evidence of tumor staining. RESULTS This study demonstrated consistent staining of the tumor at only slightly lower ICG doses than previously described, however uptake at the tumor margins was evident at much lower doses. Thus the combination of ICG and RMP-7 administered preoperatively may provide visual enhancement of an infiltrating tumor and its margins to help facilitate a radical tumor removal.
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Affiliation(s)
- Gavin W Britz
- Department of Neurological Surgery, University of Washington, Seattle, USA
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Emerich DF, Dean RL, Osborn C, Bartus RT. The development of the bradykinin agonist labradimil as a means to increase the permeability of the blood-brain barrier: from concept to clinical evaluation. Clin Pharmacokinet 2001; 40:105-23. [PMID: 11286321 DOI: 10.2165/00003088-200140020-00003] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Labradimil (Cereport; also formerly referred to as RMP-7) is a 9-amino-acid peptide designed for selectivity for the bradykinin B2 receptor and a longer plasma half-life than bradykinin. It has been developed to increase the permeability of the blood-brain barrier (BBB) and is the first compound with selective bradykinin B2 receptor agonist properties to progress from concept design through to tests of efficacy in patients. In vitro studies demonstrate that labradimil has a longer half-life than bradykinin and selectively binds to bradykinin B2 receptors, initiating typical bradykinin-like second messenger systems, including increases in intracellular calcium and phosphatidylinositol turnover. Initial proof of principle studies using electron microscopy demonstrated that intravenous labradimil increases the permeability of the BBB by disengaging the tight junctions of the endothelial cells that comprise the BBB. Autoradiographic studies in rat models further demonstrated that labradimil increases the permeability of the BBB in gliomas. Intravenous or intra-arterial labradimil increases the uptake of many different radiolabelled tracers and chemotherapeutic agents into the tumour in a dose-related fashion. These effects are selective for the tumour and for the brain surrounding the tumour, and are particularly robust in tumour areas that are normally relatively impermeable. The increased chemotherapeutic concentrations are maintained for at least 90 minutes, well beyond the transient effects on the BBB. The increase in permeability with labradimil occurs rapidly but is transient, in that restoration of the BBB occurs very rapidly (2 to 5 minutes) following cessation of infusion. Even with continuous infusion of labradimil, spontaneous restoration of the barrier begins to occur within 10 to 20 minutes. Collectively, these data demonstrate that the B2 receptor system that modulates permeability of the BBB is highly sensitive and autoregulated and that careful attention to the timing of labradimil and the chemotherapeutic agent is important to achieve maximal effects. Survival studies in rodent models of both gliomas and metastatic tumours in the brain demonstrate that the enhanced uptake observed with the combination of labradimil and water-soluble chemotherapeutics enhances survival to a greater extent than achieved with chemotherapy alone. Finally, preliminary clinical trials in patients with gliomas provide confirmatory evidence that labradimil permeabilises the blood-brain tumour barrier and might, therefore, be used to increase delivery of agents such as carboplatin to tumours without the toxicity typically associated with dose escalation.
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Affiliation(s)
- D F Emerich
- Alkermes, Inc., Cambridge, Massachusetts, USA
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