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Snipstad S, Einen C, Kastellet AB, Fernandez JL, Mühlenpfordt M, Kurbatskaya A, Årseth C, Berg S, Bjørkøy A, Davies CDL. Ultrasound and Microbubble-Induced Reduction of Functional Vasculature Depends on the Microbubble, Tumor Type and Time After Treatment. ULTRASOUND IN MEDICINE & BIOLOGY 2024:S0301-5629(24)00337-5. [PMID: 39389855 DOI: 10.1016/j.ultrasmedbio.2024.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 08/15/2024] [Accepted: 09/05/2024] [Indexed: 10/12/2024]
Abstract
OBJECTIVE Ultrasound in combination with microbubbles can enhance accumulation and improve the distribution of various therapeutic agents in tumor tissue, leading to improved efficacy. Understanding the impact of treatment on the tumor microenvironment, concurrently with how microenvironment attributes affect treatment outcome, will be important for selecting appropriate patient cohorts in future clinical trials. The main aim of this work was to investigate the influence of ultrasound and microbubbles on the functional vasculature of cancer tissue. METHODS Four different tumor models in mice (bone, pancreatic, breast and colon cancer) were characterized with respect to vascular parameters using contrast-enhanced ultrasound imaging. The effect of treatment with microbubbles and ultrasound was then investigated using immunohistochemistry and confocal microscopy, quantifying the total amount of vasculature and fraction of functional vessels. Two different microbubbles were used, the clinical contrast agent SonoVue and the large bubbles generated by Acoustic Cluster Therapy (ACT), tailored for therapeutic purposes. RESULTS The colon cancer model displayed slower flow but a higher vascular volume than the other models. The pancreatic model showed the fastest flow but also the lowest vascular volume. Ultrasound and SonoVue transiently reduced the amount of functional vasculature in breast and colon tumors immediately after treatment. No reduction was observed for ACT, likely due to shorter ultrasound pulses and lower pressures applied. CONCLUSION Variation between tumor models due to tissue characteristics emphasizes the importance of evaluating treatment suitability in the specific tissue of interest, as altered perfusion could have a large impact on drug delivery and therapeutic outcome.
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Affiliation(s)
- Sofie Snipstad
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Cancer Clinic, St. Olav's Hospital, Trondheim, Norway.
| | - Caroline Einen
- Porelab and Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Andrea Berge Kastellet
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jessica Lage Fernandez
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Melina Mühlenpfordt
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Anna Kurbatskaya
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Charlotte Årseth
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Sigrid Berg
- Department of Health Research, SINTEF Digital, Trondheim, Norway
| | - Astrid Bjørkøy
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
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Shakya G, Cattaneo M, Guerriero G, Prasanna A, Fiorini S, Supponen O. Ultrasound-responsive microbubbles and nanodroplets: A pathway to targeted drug delivery. Adv Drug Deliv Rev 2024; 206:115178. [PMID: 38199257 DOI: 10.1016/j.addr.2023.115178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/21/2023] [Accepted: 12/31/2023] [Indexed: 01/12/2024]
Abstract
Ultrasound-responsive agents have shown great potential as targeted drug delivery agents, effectively augmenting cell permeability and facilitating drug absorption. This review focuses on two specific agents, microbubbles and nanodroplets, and provides a sequential overview of their drug delivery process. Particular emphasis is given to the mechanical response of the agents under ultrasound, and the subsequent physical and biological effects on the cells. Finally, the state-of-the-art in their pre-clinical and clinical implementation are discussed. Throughout the review, major challenges that need to be overcome in order to accelerate their clinical translation are highlighted.
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Affiliation(s)
- Gazendra Shakya
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Marco Cattaneo
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Giulia Guerriero
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Anunay Prasanna
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Samuele Fiorini
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Outi Supponen
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland.
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Fernandez JL, Snipstad S, Bjørkøy A, Davies CDL. Real-Time Multiphoton Intravital Microscopy of Drug Extravasation in Tumours during Acoustic Cluster Therapy. Cells 2024; 13:349. [PMID: 38391962 PMCID: PMC10887035 DOI: 10.3390/cells13040349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/24/2024] Open
Abstract
Optimising drug delivery to tumours remains an obstacle to effective cancer treatment. A prerequisite for successful chemotherapy is that the drugs reach all tumour cells. The vascular network of tumours, extravasation across the capillary wall and penetration throughout the extracellular matrix limit the delivery of drugs. Ultrasound combined with microbubbles has been shown to improve the therapeutic response in preclinical and clinical studies. Most studies apply microbubbles designed as ultrasound contrast agents. Acoustic Cluster Therapy (ACT®) is a novel approach based on ultrasound-activated microbubbles, which have a diameter 5-10 times larger than regular contrast agent microbubbles. An advantage of using such large microbubbles is that they are in contact with a larger part of the capillary wall, and the oscillating microbubbles exert more effective biomechanical effects on the vessel wall. In accordance with this, ACT® has shown promising therapeutic results in combination with various drugs and drug-loaded nanoparticles. Knowledge of the mechanism and behaviour of drugs and microbubbles is needed to optimise ACT®. Real-time intravital microscopy (IVM) is a useful tool for such studies. This paper presents the experimental setup design for visualising ACT® microbubbles within the vasculature of tumours implanted in dorsal window (DW) chambers. It presents ultrasound setups, the integration and alignment of the ultrasound field with the optical system in live animal experiments, and the methodologies for visualisation and analysing the recordings. Dextran was used as a fluorescent marker to visualise the blood vessels and to trace drug extravasation and penetration into the extracellular matrix. The results reveal that the experimental setup successfully recorded the kinetics of extravasation and penetration distances into the extracellular matrix, offering a deeper understanding of ACT's mechanisms and potential in localised drug delivery.
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Affiliation(s)
- Jessica Lage Fernandez
- Department of Physics, Norwegian University of Science and Technology, 7034 Trondheim, Norway; (S.S.); (A.B.); (C.d.L.D.)
| | - Sofie Snipstad
- Department of Physics, Norwegian University of Science and Technology, 7034 Trondheim, Norway; (S.S.); (A.B.); (C.d.L.D.)
- Cancer Clinic, St. Olavs Hospital, 7030 Trondheim, Norway
| | - Astrid Bjørkøy
- Department of Physics, Norwegian University of Science and Technology, 7034 Trondheim, Norway; (S.S.); (A.B.); (C.d.L.D.)
| | - Catharina de Lange Davies
- Department of Physics, Norwegian University of Science and Technology, 7034 Trondheim, Norway; (S.S.); (A.B.); (C.d.L.D.)
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Mühlenpfordt M, Olsen EB, Kotopoulis S, Torp SH, Snipstad S, Davies CDL, Olsman M. Real-Time Intravital Imaging of Acoustic Cluster Therapy-Induced Vascular Effects in the Murine Brain. ULTRASOUND IN MEDICINE & BIOLOGY 2023; 49:1212-1226. [PMID: 36858913 DOI: 10.1016/j.ultrasmedbio.2023.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 12/18/2022] [Accepted: 01/09/2023] [Indexed: 05/11/2023]
Abstract
OBJECTIVE The blood-brain barrier (BBB) is an obstacle for cerebral drug delivery. Controlled permeabilization of the barrier by external stimuli can facilitate the delivery of drugs to the brain. Acoustic Cluster Therapy (ACT®) is a promising strategy for transiently and locally increasing the permeability of the BBB to macromolecules and nanoparticles. However, the mechanism underlying the induced permeability change and subsequent enhanced accumulation of co-injected molecules requires further elucidation. METHODS In this study, the behavior of ACT® bubbles in microcapillaries in the murine brain was observed using real-time intravital multiphoton microscopy. For this purpose, cranial windows aligned with a ring transducer centered around an objective were mounted to the skull of mice. Dextrans labeled with 2 MDa fluorescein isothiocyanate (FITC) were injected to delineate the blood vessels and to visualize extravasation. DISCUSSION Activated ACT® bubbles were observed to alter the blood flow, inducing transient and local increases in the fluorescence intensity of 2 MDa FITC-dextran and subsequent extravasation in the form of vascular outpouchings. The observations indicate that ACT® induced a transient vascular leakage without causing substantial damage to the vessels in the brain. CONCLUSION The study gave novel insights into the mechanism underlying ACT®-induced enhanced BBB permeability which will be important considering treatment optimization for a safe and efficient clinical translation of ACT®.
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Affiliation(s)
- Melina Mühlenpfordt
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Exact Therapeutics AS, Oslo, Norway.
| | - Emma Bøe Olsen
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Spiros Kotopoulis
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Sverre H Torp
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Department of Pathology, St. Olav's Hospital, Trondheim University Hospital Trondheim, Norway
| | - Sofie Snipstad
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Cancer Clinic, St. Olav's Hospital, Trondheim, Norway
| | | | - Marieke Olsman
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
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Effect of acoustic cluster therapy (ACT®) combined with chemotherapy in a patient-derived xenograft mouse model of pancreatic cancer. J Control Release 2022; 352:1134-1143. [PMID: 36372388 DOI: 10.1016/j.jconrel.2022.11.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 09/06/2022] [Accepted: 11/07/2022] [Indexed: 11/23/2022]
Abstract
Pancreatic ductal adenocarcinomas respond poorly to chemotherapy, in part due to the dense tumor stroma that hinders drug delivery. Ultrasound (US) in combination with microbubbles has previously shown promise as a means to improve drug delivery, and the therapeutic efficacy of ultrasound-mediated drug delivery is currently being evaluated in multiple clinical trials. However, most of these utilize echogenic contrast agents engineered for imaging, which might not be optimal compared to specialized formulations tailored for drug delivery. In this study, we evaluated the in vivo efficacy of phase-shifting microbubble-microdroplet clusters that, upon insonation, form bubbles in the size range of 20-30 μm. We developed a patient-derived xenograft model of pancreatic cancer implanted in mice that largely retained the stromal content of the originating tumor and compared tumor growth in mice given chemotherapeutics (nab-paclitaxel plus gemcitabine or liposomal irinotecan) with mice given the same chemotherapeutics in addition to ultrasound and acoustic cluster therapy. We found that acoustic cluster therapy significantly improved the effect of both chemotherapeutic regimens and resulted in 7.2 times higher odds of complete remission of the tumor compared to the chemotherapeutics alone.
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Benton RP, Al Rifai N, Stone K, Clark A, Zhang B, Haworth KJ. Impact of Perfluoropentane Microdroplets Diameter and Concentration on Acoustic Droplet Vaporization Transition Efficiency and Oxygen Scavenging. Pharmaceutics 2022; 14:pharmaceutics14112392. [PMID: 36365210 PMCID: PMC9694497 DOI: 10.3390/pharmaceutics14112392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/25/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
Acoustic droplet vaporization is the ultrasound-mediated phase change of liquid droplets into gas microbubbles. Following the phase change, oxygen diffuses from the surrounding fluid into the microbubble. An in vitro model was used to study the effects of droplet diameter, the presence of an ultrasound contrast agent, ultrasound duty cycle, and droplet concentration on the magnitude of oxygen scavenging in oxygenated deionized water. Perfluoropentane droplets were manufactured through a microfluidic approach at nominal diameters of 1, 3, 5, 7, 9, and 12 µm and studied at concentrations varying from 5.1 × 10-5 to 6.3 × 10-3 mL/mL. Droplets were exposed to an ultrasound transduced by an EkoSonicTM catheter (2.35 MHz, 47 W, and duty cycles of 1.70%, 2.34%, or 3.79%). Oxygen scavenging and the total volume of perfluoropentane that phase-transitioned increased with droplet concentration. The ADV transition efficiency decreased with increasing droplet concentration. The increasing duty cycle resulted in statistically significant increases in oxygen scavenging for 1, 3, 5, and 7 µm droplets, although the increase was smaller than when the droplet diameter or concentration were increased. Under the ultrasound conditions tested, droplet diameter and concentration had the greatest impact on the amount of ADV and subsequent oxygen scavenging occurred, which should be considered when using ADV-mediated oxygen scavenging in therapeutic ultrasounds.
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Affiliation(s)
- Rachel P. Benton
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Nour Al Rifai
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Kateryna Stone
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Abigail Clark
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Bin Zhang
- Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Kevin J. Haworth
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, University of Cincinnati, Cincinnati, OH 45267, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, OH 45229, USA
- Correspondence: ; Tel.: +1-513-558-3536
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Wang J, Li Z, Pan M, Fiaz M, Hao Y, Yan Y, Sun L, Yan F. Ultrasound-mediated blood-brain barrier opening: An effective drug delivery system for theranostics of brain diseases. Adv Drug Deliv Rev 2022; 190:114539. [PMID: 36116720 DOI: 10.1016/j.addr.2022.114539] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 09/04/2022] [Accepted: 09/11/2022] [Indexed: 01/24/2023]
Abstract
Blood-brain barrier (BBB) remains a significant obstacle to drug therapy for brain diseases. Focused ultrasound (FUS) combined with microbubbles (MBs) can locally and transiently open the BBB, providing a potential strategy for drug delivery across the BBB into the brain. Nowadays, taking advantage of this technology, many therapeutic agents, such as antibodies, growth factors, and nanomedicine formulations, are intensively investigated across the BBB into specific brain regions for the treatment of various brain diseases. Several preliminary clinical trials also have demonstrated its safety and good tolerance in patients. This review gives an overview of the basic mechanisms, ultrasound contrast agents, evaluation or monitoring methods, and medical applications of FUS-mediated BBB opening in glioblastoma, Alzheimer's disease, and Parkinson's disease.
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Affiliation(s)
- Jieqiong Wang
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai 201206, China
| | - Zhenzhou Li
- Department of Ultrasound, The Second People's Hospital of Shenzhen, The First Affiliated Hospital of Shenzhen University, Shenzhen 518061, China
| | - Min Pan
- Shenzhen Hospital of Guangzhou University of Chinese Medicine, Shenzhen 518034, China
| | - Muhammad Fiaz
- Department of Radiology, Azra Naheed Medical College, Lahore, Pakistan
| | - Yongsheng Hao
- Center for Cell and Gene Circuit Design, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yiran Yan
- Department of Orthopedics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Litao Sun
- Cancer Center, Department of Ultrasound Medicine, Zhejiang Provincial People's Hospital (Affiliated People's Hospital, Hangzhou Medical College), Hangzhou, Zhejiang 310014, China.
| | - Fei Yan
- Center for Cell and Gene Circuit Design, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
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8
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van Wamel A, Mühlenpfordt M, Hansen R, Healey A, Villanueva FS, Kotopoulis S, Davies CDL, Chen X. Ultrafast Microscopy Imaging of Acoustic Cluster Therapy Bubbles: Activation and Oscillation. ULTRASOUND IN MEDICINE & BIOLOGY 2022; 48:1840-1857. [PMID: 35773079 DOI: 10.1016/j.ultrasmedbio.2022.05.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 02/15/2022] [Accepted: 05/10/2022] [Indexed: 06/15/2023]
Abstract
Acoustic Cluster Therapy (ACT®) is a platform for improving drug delivery and has had promising pre-clinical results. A clinical trial is ongoing. ACT® is based on microclusters of microbubbles-microdroplets that, when sonicated, form a large ACT® bubble. The aim of this study was to obtain new knowledge on the dynamic formation and oscillations of ACT® bubbles by ultrafast optical imaging in a microchannel. The high-speed recordings revealed the microbubble-microdroplet fusion, and the gas in the microbubble acted as a vaporization seed for the microdroplet. Subsequently, the bubble grew by gas diffusion from the surrounding medium and became a large ACT® bubble with a diameter of 5-50 μm. A second ultrasound exposure at lower frequency caused the ACT® bubble to oscillate. The recorded oscillations were compared with simulations using the modified Rayleigh-Plesset equation. A term accounting for the physical boundary imposed by the microchannel wall was included. The recorded oscillation amplitudes were approximately 1-2 µm, hence similar to oscillations of smaller contrast agent microbubbles. These findings, together with our previously reported promising pre-clinical therapeutic results, suggest that these oscillations covering a large part of the vessel wall because of the large bubble volume can substantially improve therapeutic outcome.
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Affiliation(s)
- Annemieke van Wamel
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Melina Mühlenpfordt
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Rune Hansen
- Department of Health Research, SINTEF Digital, Trondheim, Norway; Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | | | - Flordeliza S Villanueva
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Spiros Kotopoulis
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | | | - Xucai Chen
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Ni N, Wang W, Sun Y, Sun X, Leong DT. Inducible endothelial leakiness in nanotherapeutic applications. Biomaterials 2022; 287:121640. [PMID: 35772348 DOI: 10.1016/j.biomaterials.2022.121640] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 05/23/2022] [Accepted: 06/14/2022] [Indexed: 11/02/2022]
Abstract
All intravenous delivered nanomedicine needs to escape from the blood vessel to exert their therapeutic efficacy at their designated site of action. Failure to do so increases the possibility of detrimental side effects and negates their therapeutic intent. Many powerful anticancer nanomedicine strategies rely solely on the tumor derived enhanced permeability and retention (EPR) effect for the only mode of escaping from the tumor vasculature. However, not all tumors have the EPR effect nor can the EPR effect be induced or controlled for its location and timeliness. In recent years, there have been exciting developments along the lines of inducing endothelial leakiness at the tumor to decrease the dependence of EPR. Physical disruption of the endothelial-endothelial cell junctions with coordinated biological intrinsic pathways have been proposed that includes various modalities like ultrasound, radiotherapy, heat and even nanoparticles, appear to show good progress towards the goal of inducing endothelial leakiness. This review explains the intricate and complex biological background behind the endothelial cells with linkages on how updated reported nanomedicine strategies managed to induce endothelial leakiness. This review will also end off with fresh insights on where the future of inducible endothelial leakiness holds.
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Affiliation(s)
- Nengyi Ni
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore
| | - Weiyi Wang
- School of Chemistry and Pharmaceutical Engineering, Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250000, China
| | - Yu Sun
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore; Department of Ultrasound in Medicine, The Second Affiliated Hospital of Zhejiang University School of Medicine, No.88 Jiefang Road, Shangcheng District, Hangzhou, 310009, PR China
| | - Xiao Sun
- School of Chemistry and Pharmaceutical Engineering, Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250000, China.
| | - David Tai Leong
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore.
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Kaur J, Gulati M, Kapoor B, Jha NK, Gupta PK, Gupta G, Chellappan DK, Devkota HP, Prasher P, Ansari MS, Aba Alkhayl FF, Arshad MF, Morris A, Choonara YE, Adams J, Dua K, Singh SK. Advances in designing of polymeric micelles for biomedical application in brain related diseases. Chem Biol Interact 2022; 361:109960. [DOI: 10.1016/j.cbi.2022.109960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 04/11/2022] [Accepted: 04/22/2022] [Indexed: 12/12/2022]
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Delaney LJ, Isguven S, Eisenbrey JR, Hickok NJ, Forsberg F. Making waves: how ultrasound-targeted drug delivery is changing pharmaceutical approaches. MATERIALS ADVANCES 2022; 3:3023-3040. [PMID: 35445198 PMCID: PMC8978185 DOI: 10.1039/d1ma01197a] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/23/2022] [Indexed: 05/06/2023]
Abstract
Administration of drugs through oral and intravenous routes is a mainstay of modern medicine, but this approach suffers from limitations associated with off-target side effects and narrow therapeutic windows. It is often apparent that a controlled delivery of drugs, either localized to a specific site or during a specific time, can increase efficacy and bypass problems with systemic toxicity and insufficient local availability. To overcome some of these issues, local delivery systems have been devised, but most are still restricted in terms of elution kinetics, duration, and temporal control. Ultrasound-targeted drug delivery offers a powerful approach to increase delivery, therapeutic efficacy, and temporal release of drugs ranging from chemotherapeutics to antibiotics. The use of ultrasound can focus on increasing tissue sensitivity to the drug or actually be a critical component of the drug delivery. The high spatial and temporal resolution of ultrasound enables precise location, targeting, and timing of drug delivery and tissue sensitization. Thus, this noninvasive, non-ionizing, and relatively inexpensive modality makes the implementation of ultrasound-mediated drug delivery a powerful method that can be readily translated into the clinical arena. This review covers key concepts and areas applied in the design of different ultrasound-mediated drug delivery systems across a variety of clinical applications.
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Affiliation(s)
- Lauren J Delaney
- Department of Radiology, Thomas Jefferson University 132 S. 10th Street, Main 763 Philadelphia PA 19107 USA +1 (215) 955-4870
| | - Selin Isguven
- Department of Radiology, Thomas Jefferson University 132 S. 10th Street, Main 763 Philadelphia PA 19107 USA +1 (215) 955-4870
- Department of Orthopaedic Surgery, Thomas Jefferson University, 1015 Walnut Street Philadelphia PA 19107 USA
| | - John R Eisenbrey
- Department of Radiology, Thomas Jefferson University 132 S. 10th Street, Main 763 Philadelphia PA 19107 USA +1 (215) 955-4870
| | - Noreen J Hickok
- Department of Orthopaedic Surgery, Thomas Jefferson University, 1015 Walnut Street Philadelphia PA 19107 USA
| | - Flemming Forsberg
- Department of Radiology, Thomas Jefferson University 132 S. 10th Street, Main 763 Philadelphia PA 19107 USA +1 (215) 955-4870
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Snipstad S, Vikedal K, Maardalen M, Kurbatskaya A, Sulheim E, Davies CDL. Ultrasound and microbubbles to beat barriers in tumors: Improving delivery of nanomedicine. Adv Drug Deliv Rev 2021; 177:113847. [PMID: 34182018 DOI: 10.1016/j.addr.2021.113847] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/18/2021] [Accepted: 06/22/2021] [Indexed: 12/18/2022]
Abstract
Successful delivery of drugs and nanomedicine to tumors requires a functional vascular network, extravasation across the capillary wall, penetration through the extracellular matrix, and cellular uptake. Nanomedicine has many merits, but penetration deep into the tumor interstitium remains a challenge. Failure of cancer treatment can be caused by insufficient delivery of the therapeutic agents. After intravenous administration, nanomedicines are often found in off-target organs and the tumor extracellular matrix close to the capillary wall. With circulating microbubbles, ultrasound exposure focused toward the tumor shows great promise in improving the delivery of therapeutic agents. In this review, we address the impact of focused ultrasound and microbubbles to overcome barriers for drug delivery such as perfusion, extravasation, and transport through the extracellular matrix. Furthermore, we discuss the induction of an immune response with ultrasound and delivery of immunotherapeutics. The review discusses mainly preclinical results and ends with a summary of ongoing clinical trials.
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Affiliation(s)
- Sofie Snipstad
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Department of Biotechnology and Nanomedicine, SINTEF Industry, Trondheim, Norway; Cancer Clinic, St. Olav's Hospital, Trondheim, Norway.
| | - Krister Vikedal
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Matilde Maardalen
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Anna Kurbatskaya
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Einar Sulheim
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Department of Biotechnology and Nanomedicine, SINTEF Industry, Trondheim, Norway
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Ultrasound-Enabled Therapeutic Delivery and Regenerative Medicine: Physical and Biological Perspectives. ACS Biomater Sci Eng 2021; 7:4371-4387. [PMID: 34460238 DOI: 10.1021/acsbiomaterials.1c00276] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The role of ultrasound in medicine and biological sciences is expanding rapidly beyond its use in conventional diagnostic imaging. Numerous studies have reported the effects of ultrasound on cellular and tissue physiology. Advances in instrumentation and electronics have enabled successful in vivo applications of therapeutic ultrasound. Despite path breaking advances in understanding the biophysical and biological mechanisms at both microscopic and macroscopic scales, there remain substantial gaps. With the progression of research in this area, it is important to take stock of the current understanding of the field and to highlight important areas for future work. We present herein key developments in the biological applications of ultrasound especially in the context of nanoparticle delivery, drug delivery, and regenerative medicine. We conclude with a brief perspective on the current promise, limitations, and future directions for interfacing ultrasound technology with biological systems, which could provide guidance for future investigations in this interdisciplinary area.
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Ho YJ, Huang CC, Fan CH, Liu HL, Yeh CK. Ultrasonic technologies in imaging and drug delivery. Cell Mol Life Sci 2021; 78:6119-6141. [PMID: 34297166 PMCID: PMC11072106 DOI: 10.1007/s00018-021-03904-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/13/2021] [Accepted: 07/19/2021] [Indexed: 12/14/2022]
Abstract
Ultrasonic technologies show great promise for diagnostic imaging and drug delivery in theranostic applications. The development of functional and molecular ultrasound imaging is based on the technical breakthrough of high frame-rate ultrasound. The evolution of shear wave elastography, high-frequency ultrasound imaging, ultrasound contrast imaging, and super-resolution blood flow imaging are described in this review. Recently, the therapeutic potential of the interaction of ultrasound with microbubble cavitation or droplet vaporization has become recognized. Microbubbles and phase-change droplets not only provide effective contrast media, but also show great therapeutic potential. Interaction with ultrasound induces unique and distinguishable biophysical features in microbubbles and droplets that promote drug loading and delivery. In particular, this approach demonstrates potential for central nervous system applications. Here, we systemically review the technological developments of theranostic ultrasound including novel ultrasound imaging techniques, the synergetic use of ultrasound with microbubbles and droplets, and microbubble/droplet drug-loading strategies for anticancer applications and disease modulation. These advancements have transformed ultrasound from a purely diagnostic utility into a promising theranostic tool.
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Affiliation(s)
- Yi-Ju Ho
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Chung Huang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
- Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan
| | - Ching-Hsiang Fan
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
- Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan
| | - Hao-Li Liu
- Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan.
| | - Chih-Kuang Yeh
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan.
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15
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Krafft MP, Riess JG. Therapeutic oxygen delivery by perfluorocarbon-based colloids. Adv Colloid Interface Sci 2021; 294:102407. [PMID: 34120037 DOI: 10.1016/j.cis.2021.102407] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 03/18/2021] [Accepted: 03/25/2021] [Indexed: 02/06/2023]
Abstract
After the protocol-related indecisive clinical trial of Oxygent, a perfluorooctylbromide/phospholipid nanoemulsion, in cardiac surgery, that often unduly assigned the observed untoward effects to the product, the development of perfluorocarbon (PFC)-based O2 nanoemulsions ("blood substitutes") has come to a low. Yet, significant further demonstrations of PFC O2-delivery efficacy have continuously been reported, such as relief of hypoxia after myocardial infarction or stroke; protection of vital organs during surgery; potentiation of O2-dependent cancer therapies, including radio-, photodynamic-, chemo- and immunotherapies; regeneration of damaged nerve, bone or cartilage; preservation of organ grafts destined for transplantation; and control of gas supply in tissue engineering and biotechnological productions. PFC colloids capable of augmenting O2 delivery include primarily injectable PFC nanoemulsions, microbubbles and phase-shift nanoemulsions. Careful selection of PFC and other colloid components is critical. The basics of O2 delivery by PFC nanoemulsions will be briefly reminded. Improved knowledge of O2 delivery mechanisms has been acquired. Advanced, size-adjustable O2-delivering nanoemulsions have been designed that have extended room-temperature shelf-stability. Alternate O2 delivery options are being investigated that rely on injectable PFC-stabilized microbubbles or phase-shift PFC nanoemulsions. The latter combine prolonged circulation in the vasculature, capacity for penetrating tumor tissues, and acute responsiveness to ultrasound and other external stimuli. Progress in microbubble and phase-shift emulsion engineering, control of phase-shift activation (vaporization), understanding and control of bubble/ultrasound/tissue interactions is discussed. Control of the phase-shift event and of microbubble size require utmost attention. Further PFC-based colloidal systems, including polymeric micelles, PFC-loaded organic or inorganic nanoparticles and scaffolds, have been devised that also carry substantial amounts of O2. Local, on-demand O2 delivery can be triggered by external stimuli, including focused ultrasound irradiation or tumor microenvironment. PFC colloid functionalization and targeting can help adjust their properties for specific indications, augment their efficacy, improve safety profiles, and expand the range of their indications. Many new medical and biotechnological applications involving fluorinated colloids are being assessed, including in the clinic. Further uses of PFC-based colloidal nanotherapeutics will be briefly mentioned that concern contrast diagnostic imaging, including molecular imaging and immune cell tracking; controlled delivery of therapeutic energy, as for noninvasive surgical ablation and sonothrombolysis; and delivery of drugs and genes, including across the blood-brain barrier. Even when the fluorinated colloids investigated are designed for other purposes than O2 supply, they will inevitably also carry and deliver a certain amount of O2, and may thus be considered for O2 delivery or co-delivery applications. Conversely, O2-carrying PFC nanoemulsions possess by nature a unique aptitude for 19F MR imaging, and hence, cell tracking, while PFC-stabilized microbubbles are ideal resonators for ultrasound contrast imaging and can undergo precise manipulation and on-demand destruction by ultrasound waves, thereby opening multiple theranostic opportunities.
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Affiliation(s)
- Marie Pierre Krafft
- University of Strasbourg, Institut Charles Sadron (CNRS), 23 rue du Loess, 67034 Strasbourg, France.
| | - Jean G Riess
- Harangoutte Institute, 68160 Ste Croix-aux-Mines, France
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16
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Drug Delivery by Ultrasound-Responsive Nanocarriers for Cancer Treatment. Pharmaceutics 2021; 13:pharmaceutics13081135. [PMID: 34452096 PMCID: PMC8397943 DOI: 10.3390/pharmaceutics13081135] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/28/2021] [Accepted: 06/29/2021] [Indexed: 12/13/2022] Open
Abstract
Conventional cancer chemotherapies often exhibit insufficient therapeutic outcomes and dose-limiting toxicity. Therefore, there is a need for novel therapeutics and formulations with higher efficacy, improved safety, and more favorable toxicological profiles. This has promoted the development of nanomedicines, including systems for drug delivery, but also for imaging and diagnostics. Nanoparticles loaded with drugs can be designed to overcome several biological barriers to improving efficiency and reducing toxicity. In addition, stimuli-responsive nanocarriers are able to release their payload on demand at the tumor tissue site, preventing premature drug loss. This review focuses on ultrasound-triggered drug delivery by nanocarriers as a versatile, cost-efficient, non-invasive technique for improving tissue specificity and tissue penetration, and for achieving high drug concentrations at their intended site of action. It highlights aspects relevant for ultrasound-mediated drug delivery, including ultrasound parameters and resulting biological effects. Then, concepts in ultrasound-mediated drug delivery are introduced and a comprehensive overview of several types of nanoparticles used for this purpose is given. This includes an in-depth compilation of the literature on the various in vivo ultrasound-responsive drug delivery systems. Finally, toxicological and safety considerations regarding ultrasound-mediated drug delivery with nanocarriers are discussed.
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17
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Olsman M, Mühlenpfordt M, Olsen EB, Torp SH, Kotopoulis S, Rijcken CJF, Hu Q, Thewissen M, Snipstad S, de Lange Davies C. Acoustic Cluster Therapy (ACT®) enhances accumulation of polymeric micelles in the murine brain. J Control Release 2021; 337:285-295. [PMID: 34274386 DOI: 10.1016/j.jconrel.2021.07.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/22/2021] [Accepted: 07/13/2021] [Indexed: 12/12/2022]
Abstract
The restrictive nature of the blood-brain barrier (BBB) prevents efficient treatment of many brain diseases. Focused ultrasound in combination with microbubbles has shown to safely and transiently increase BBB permeability. Here, the potential of Acoustic Cluster Therapy (ACT®), a microbubble platform specifically engineered for theranostic purposes, to increase the permeability of the BBB and improve accumulation of IRDye® 800CW-PEG and core-crosslinked polymeric micelles (CCPM) in the murine brain, was studied. Contrast enhanced magnetic resonance imaging (MRI) showed increased BBB permeability in all animals after ACT®. Near infrared fluorescence (NIRF) images of excised brains 1 h post ACT® revealed an increased accumulation of the IRDye® 800CW-PEG (5.2-fold) and CCPM (3.7-fold) in ACT®-treated brains compared to control brains, which was retained up to 24 h post ACT®. Confocal laser scanning microscopy (CLSM) showed improved extravasation and penetration of CCPM into the brain parenchyma after ACT®. Histological examination of brain sections showed no treatment related tissue damage. This study demonstrated that ACT® increases the permeability of the BBB and enhances accumulation of macromolecules and clinically relevant nanoparticles to the brain, taking a principal step in enabling improved treatment of various brain diseases.
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Affiliation(s)
- Marieke Olsman
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Melina Mühlenpfordt
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway.
| | - Emma Bøe Olsen
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Sverre H Torp
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Department of Pathology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Spiros Kotopoulis
- National Centre for Ultrasound in Gastroenterology, Haukeland University Hospital, Bergen, Norway; Exact Therapeutics, Oslo, Norway
| | | | - Qizhi Hu
- Cristal Therapeutics, Maastricht, the Netherlands
| | | | - Sofie Snipstad
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Cancer Clinic, St. Olavs Hospital, Trondheim, Norway
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18
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Wu Q, Mannaris C, May JP, Bau L, Polydorou A, Ferri S, Carugo D, Evans ND, Stride E. Investigation of the Acoustic Vaporization Threshold of Lipid-Coated Perfluorobutane Nanodroplets Using Both High-Speed Optical Imaging and Acoustic Methods. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:1826-1843. [PMID: 33820668 DOI: 10.1016/j.ultrasmedbio.2021.02.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 02/10/2021] [Accepted: 02/19/2021] [Indexed: 06/12/2023]
Abstract
A combination of ultrahigh-speed optical imaging (5 × 106 frames/s), B-mode ultrasound and passive cavitation detection was used to study the vaporization process and determine both the acoustic droplet vaporization (ADV) and inertial cavitation (IC) thresholds of phospholipid-coated perfluorobutane nanodroplets (PFB NDs, diameter = 237 ± 16 nm). PFB NDs have not previously been studied with ultrahigh-speed imaging and were observed to form individual microbubbles (1-10 μm) within two to three cycles and subsequently larger bubble clusters (10-50 μm). The ADV and IC thresholds did not statistically significantly differ and decreased with increasing pulse length (20-20,000 cycles), pulse repetition frequency (1-100 Hz), concentration (108-1010 NDs/mL), temperature (20°C-45°C) and decreasing frequency (1.5-0.5 MHz). Overall, the results indicate that at frequencies of 0.5, 1.0 and 1.5 MHz, PFB NDs can be vaporized at moderate peak negative pressures (<2.0 MPa), pulse lengths and pulse repetition frequencies. This finding is encouraging for the use of PFB NDs as cavitation agents, as these conditions are comparable to those required to achieve therapeutic effects with microbubbles, unlike those reported for higher-boiling-point NDs. The differences between the optically and acoustically determined ADV thresholds, however, suggest that application-specific thresholds should be defined according to the biological/therapeutic effect of interest.
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Affiliation(s)
- Qiang Wu
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, Oxford, United Kingdom
| | - Christophoros Mannaris
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, Oxford, United Kingdom
| | - Jonathan P May
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom; Bone and Joint Research Group, Human Development and Health, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Luca Bau
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, Oxford, United Kingdom
| | - Anastasia Polydorou
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom; Bone and Joint Research Group, Human Development and Health, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Sara Ferri
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom; Bone and Joint Research Group, Human Development and Health, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Dario Carugo
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom; Department of Pharmaceutics, UCL School of Pharmacy, University College London, London, UK
| | - Nicholas D Evans
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom; Bone and Joint Research Group, Human Development and Health, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, Oxford, United Kingdom.
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19
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Zhang C, Li Y, Ma X, He W, Liu C, Liu Z. Functional micro/nanobubbles for ultrasound medicine and visualizable guidance. Sci China Chem 2021; 64:899-914. [PMID: 33679901 PMCID: PMC7921288 DOI: 10.1007/s11426-020-9945-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 01/18/2021] [Indexed: 12/28/2022]
Abstract
Chemically functionalized gas-filled bubbles with a versatile micro/nano-sized scale have witnessed a long history of developments and emerging applications in disease diagnosis and treatments. In combination with ultrasound and image-guidance, micro/nanobubbles have been endowed with the capabilities of biomedical imaging, drug delivery, gene transfection and disease-oriented therapy. As an external stimulus, ultrasound (US)-mediated targeting treatments have been achieving unprecedented efficiency. Nowadays, US is playing a crucial role in visualizing biological/pathological changes in lives as a reliable imaging technique and a powerful therapeutic tool. This review retrospects the history of ultrasound, the chemistry of functionalized agents and summarizes recent advancements of functional micro/nanobubbles as US contrast agents in preclinical and transclinical research. Latest ultrasound-based treatment modalities in association with functional micro/nanobubbles have been highlighted as their great potentials for disease precision therapy. It is believed that these state-of-the-art micro/nanobubbles will become a booster for ultrasound medicine and visualizable guidance to serve future human healthcare in a more comprehensive and practical manner.
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Affiliation(s)
- Chen Zhang
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072 China
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin, 300072 China
| | - Yihong Li
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072 China
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin, 300072 China
| | - Xinyong Ma
- Division of Academic & Cultural Activities, Academic Divisions of the Chinese Academy of Sciences, Beijing, 100190 China
| | - Wenxin He
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072 China
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin, 300072 China
| | - Chenxi Liu
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072 China
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin, 300072 China
| | - Zhe Liu
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072 China
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin, 300072 China
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20
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Borden MA, Shakya G, Upadhyay A, Song KH. Acoustic Nanodrops for Biomedical Applications. Curr Opin Colloid Interface Sci 2020; 50:101383. [PMID: 33100885 PMCID: PMC7581261 DOI: 10.1016/j.cocis.2020.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Acoustic nanodrops are designed to vaporize into ultrasound-responsive microbubbles, which presents certain challenges nonexistent for conventional nano-emulsions. The requirements of biocompatibility, vaporizability and colloidal stability has focused research on perfluorocarbons (PFCs). Shorter PFCs yield better vaporizability via their lower critical temperature, but they also dissolve more easily owing to their higher vapor pressure and solubility. Thus, acoustic nanodrops have required a tradeoff between vaporizability and colloidal stability in vivo. The recent advent of vaporizable endoskeletal droplets, which are both stable and vaporizable, may have solved this problem. The purpose of this review is to justify this premise by pointing out the beneficial properties of acoustic nanodrops, providing an analysis of vaporization and dissolution mechanisms, and reviewing current biomedical applications.
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Affiliation(s)
- Mark A. Borden
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
| | - Gazendra Shakya
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
| | - Awaneesh Upadhyay
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
| | - Kang-Ho Song
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
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21
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Andersen KK, Frijlink ME, Johansen TF, Hoff L. A Dual-Frequency Coupled Resonator Transducer. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2020; 67:2119-2129. [PMID: 32746159 DOI: 10.1109/tuffc.2020.2995305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
New ultrasound-mediated drug delivery systems, such as acoustic cluster therapy or combined imaging and therapy systems, require transducers that can operate beyond the bandwidth limitation (~100%) of conventional piezoceramic transducers. In this article, a dual-frequency coupled resonator transducer (CRT) comprised of a polymeric coupling layer with a low acoustic impedance (2-5 MRayl) sandwiched between two piezoceramic layers is investigated. Depending on the electrical configuration, the CRT exhibits two usable frequency bands. The resonance frequency of the high-frequency (HF) band can be tailored to be ~3-5 times higher than that of the low-frequency (LF) band using the stiffness in the coupling layer. The CRT's LF band was analyzed analytically, and we obtained the closed-form expressions for the LF resonance frequency. A dual-frequency CRT was designed, manufactured, and characterized acoustically, and comparisons with theory showed good agreement. The HF band exhibited a center frequency of 2.5 MHz with a -3-dB bandwidth of 70% and is suited to manipulate microbubbles or for diagnostic imaging applications. The LF band exhibited a center frequency of 0.5 MHz with a -3-dB bandwidth of 13% and is suited to induce biological effects in tissue, therein manipulation of microbubbles.
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22
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Cimorelli M, Flynn MA, Angel B, Reimold E, Fafarman A, Huneke R, Kohut A, Wrenn S. A Voltage-Sensitive Ultrasound Enhancing Agent for Myocardial Perfusion Imaging in a Rat Model. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:2388-2399. [PMID: 32593498 DOI: 10.1016/j.ultrasmedbio.2020.05.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 05/13/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
Echocardiographers with specialized expertise sometimes perform myocardial perfusion imaging using U.S. Food and Drug Administration-approved microbubbles in an off-label capacity, correlating microbubble replenishment in the near field with blood flow through the myocardium. This study reports the in vivo clinical feasibility of a voltage-sensitive ultrasound enhancing agent (UEA) for myocardial perfusion imaging. Four UEAs were injected into Sprague-Dawley rats while ultrasound images were collected to quantify brightness in the left ventricular (LV) cavity, septal wall, and posterior wall in systole and diastole. Formulation IV, a phase change agent nested within a negatively charged phospholipid bilayer, increased the tissue-to-cavity ratio in both systole and diastole in the septal wall, 6 dB, and in the posterior wall, 5 dB, while leaving the LV cavity at baseline. This outcome improves the signal of the myocardium relative to the LV cavity and shows promise as a myocardial perfusion UEA.
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Affiliation(s)
- Michael Cimorelli
- Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania, USA
| | - Michael A Flynn
- Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania, USA
| | - Brett Angel
- Cardiology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Emily Reimold
- University Laboratory Animal Resources, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Aaron Fafarman
- Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania, USA
| | - Richard Huneke
- University Laboratory Animal Resources, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Andrew Kohut
- Cardiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steven Wrenn
- Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania, USA.
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23
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Escoffre JM, de Senneville BD, Sasaki N, Derieppe M. Editorial: Bubbles, Droplets and Micelles for Acoustically-Mediated Drug/Gene Delivery. Front Pharmacol 2020; 11:954. [PMID: 32670068 PMCID: PMC7332838 DOI: 10.3389/fphar.2020.00954] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 06/11/2020] [Indexed: 11/29/2022] Open
Affiliation(s)
- Jean-Michel Escoffre
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- *Correspondence: Jean-Michel Escoffre,
| | | | - Noboru Sasaki
- Laboratory of Veterinary Internal Medicine, Department of Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Marc Derieppe
- Department of Pediatric Neuro-oncology, Princess Maxima Center for Pediatric Oncology, Utrecht, Netherlands
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24
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Sun T, Dasgupta A, Zhao Z, Nurunnabi M, Mitragotri S. Physical triggering strategies for drug delivery. Adv Drug Deliv Rev 2020; 158:36-62. [PMID: 32589905 DOI: 10.1016/j.addr.2020.06.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/06/2020] [Accepted: 06/10/2020] [Indexed: 12/14/2022]
Abstract
Physically triggered systems hold promise for improving drug delivery by enhancing the controllability of drug accumulation and release, lowering non-specific toxicity, and facilitating clinical translation. Several external physical stimuli including ultrasound, light, electric fields and magnetic fields have been used to control drug delivery and they share some common features such as spatial targeting, spatiotemporal control, and minimal invasiveness. At the same time, they possess several distinctive features in terms of interactions with biological entities and/or the extent of stimulus response. Here, we review the key advances of such systems with a focus on discussing their physical mechanisms, the design rationales, and translational challenges.
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Affiliation(s)
- Tao Sun
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Anshuman Dasgupta
- Department of Nanomedicine and Theranostics, Institute for Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany
| | - Zongmin Zhao
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Md Nurunnabi
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, TX 79902, USA
| | - Samir Mitragotri
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA.
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25
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Stride E, Segers T, Lajoinie G, Cherkaoui S, Bettinger T, Versluis M, Borden M. Microbubble Agents: New Directions. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:1326-1343. [PMID: 32169397 DOI: 10.1016/j.ultrasmedbio.2020.01.027] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/09/2020] [Accepted: 01/26/2020] [Indexed: 05/24/2023]
Abstract
Microbubble ultrasound contrast agents have now been in use for several decades and their safety and efficacy in a wide range of diagnostic applications have been well established. Recent progress in imaging technology is facilitating exciting developments in techniques such as molecular, 3-D and super resolution imaging and new agents are now being developed to meet their specific requirements. In parallel, there have been significant advances in the therapeutic applications of microbubbles, with recent clinical trials demonstrating drug delivery across the blood-brain barrier and into solid tumours. New agents are similarly being tailored toward these applications, including nanoscale microbubble precursors offering superior circulation times and tissue penetration. The development of novel agents does, however, present several challenges, particularly regarding the regulatory framework. This article reviews the developments in agents for diagnostic, therapeutic and "theranostic" applications; novel manufacturing techniques; and the opportunities and challenges for their commercial and clinical translation.
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Affiliation(s)
- Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK.
| | - Tim Segers
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Guillaume Lajoinie
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Samir Cherkaoui
- Bracco Suisse SA - Business Unit Imaging, Global R&D, Plan-les-Ouates, Switzerland
| | - Thierry Bettinger
- Bracco Suisse SA - Business Unit Imaging, Global R&D, Plan-les-Ouates, Switzerland
| | - Michel Versluis
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Mark Borden
- Mechanical Engineering Department, University of Colorado, Boulder, CO, USA
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Kooiman K, Roovers S, Langeveld SAG, Kleven RT, Dewitte H, O'Reilly MA, Escoffre JM, Bouakaz A, Verweij MD, Hynynen K, Lentacker I, Stride E, Holland CK. Ultrasound-Responsive Cavitation Nuclei for Therapy and Drug Delivery. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:1296-1325. [PMID: 32165014 PMCID: PMC7189181 DOI: 10.1016/j.ultrasmedbio.2020.01.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 12/20/2019] [Accepted: 01/07/2020] [Indexed: 05/03/2023]
Abstract
Therapeutic ultrasound strategies that harness the mechanical activity of cavitation nuclei for beneficial tissue bio-effects are actively under development. The mechanical oscillations of circulating microbubbles, the most widely investigated cavitation nuclei, which may also encapsulate or shield a therapeutic agent in the bloodstream, trigger and promote localized uptake. Oscillating microbubbles can create stresses either on nearby tissue or in surrounding fluid to enhance drug penetration and efficacy in the brain, spinal cord, vasculature, immune system, biofilm or tumors. This review summarizes recent investigations that have elucidated interactions of ultrasound and cavitation nuclei with cells, the treatment of tumors, immunotherapy, the blood-brain and blood-spinal cord barriers, sonothrombolysis, cardiovascular drug delivery and sonobactericide. In particular, an overview of salient ultrasound features, drug delivery vehicles, therapeutic transport routes and pre-clinical and clinical studies is provided. Successful implementation of ultrasound and cavitation nuclei-mediated drug delivery has the potential to change the way drugs are administered systemically, resulting in more effective therapeutics and less-invasive treatments.
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Affiliation(s)
- Klazina Kooiman
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands.
| | - Silke Roovers
- Ghent Research Group on Nanomedicines, Lab for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Simone A G Langeveld
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Robert T Kleven
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, University of Cincinnati, Cincinnati, OH, USA
| | - Heleen Dewitte
- Ghent Research Group on Nanomedicines, Lab for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, Ghent, Belgium; Laboratory for Molecular and Cellular Therapy, Medical School of the Vrije Universiteit Brussel, Jette, Belgium; Cancer Research Institute Ghent (CRIG), Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Meaghan A O'Reilly
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | | | - Ayache Bouakaz
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | - Martin D Verweij
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands; Laboratory of Acoustical Wavefield Imaging, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Kullervo Hynynen
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Ine Lentacker
- Ghent Research Group on Nanomedicines, Lab for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Christy K Holland
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, University of Cincinnati, Cincinnati, OH, USA; Department of Internal Medicine, Division of Cardiovascular Health and Disease, University of Cincinnati, Cincinnati, OH, USA
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Bush N, Healey A, Shah A, Box G, Kirkin V, Eccles S, Sontum PC, Kotopoulis S, Kvåle S, van Wamel A, Davies CDL, Bamber J. Theranostic Attributes of Acoustic Cluster Therapy and Its Use for Enhancing the Effectiveness of Liposomal Doxorubicin Treatment of Human Triple Negative Breast Cancer in Mice. Front Pharmacol 2020; 11:75. [PMID: 32153400 PMCID: PMC7044119 DOI: 10.3389/fphar.2020.00075] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 01/24/2020] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Acoustic cluster therapy (ACT) comprises co-administration of a formulation containing microbubble/microdroplet clusters (PS101), together with a regular medicinal drug (e.g., a chemotherapeutic) and local ultrasound (US) insonation of the targeted pathological tissue (e.g., the tumor). PS101 is confined to the vascular compartment and, when the clusters are exposed to regular diagnostic imaging US fields, the microdroplets undergo a phase-shift to produce bubbles with a median diameter of 22 µm when unconstrained by the capillary wall. In vivo these bubbles transiently lodge in the tumor's microvasculature. Low frequency ultrasound (300 kHz) at a low mechanical index (MI = 0.15) is then applied to drive oscillations of the deposited ACT bubbles to induce a range of biomechanical effects that locally enhance extravasation, distribution, and uptake of the co-administered drug, significantly increasing its therapeutic efficacy. METHODS In this study we investigated the therapeutic efficacy of ACT with liposomal doxorubicin for the treatment of triple negative breast cancer using orthotopic human tumor xenografts (MDA-MB-231-H.luc) in athymic mice (ICR-NCr-Foxn1nu). Doxil® (6 mg/kg, i.v.) was administered at days 0 and 21, each time immediately followed by three sequential ACT (20 ml/kg PS101) treatment procedures (n = 7-10). B-mode and nonlinear ultrasound images acquired during the activation phase were correlated to the therapeutic efficacy. RESULTS Results show that combination with ACT induces a strong increase in the therapeutic efficacy of Doxil®, with 63% of animals in complete, stable remission at end of study, vs. 10% for Doxil® alone (p < 0.02). A significant positive correlation (p < 0.004) was found between B-mode contrast enhancement during ACT activation and therapy response. These observations indicate that ACT may also be used as a theranostic agent and that ultrasound contrast enhancement during or before ACT treatment may be employed as a biomarker of therapeutic response during clinical use.
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Affiliation(s)
- Nigel Bush
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
| | | | - Anant Shah
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
| | - Gary Box
- Department of Physics, CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Vladimir Kirkin
- Department of Physics, CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Sue Eccles
- Department of Physics, CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | | | | | | | | | | | - Jeffrey Bamber
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
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Metal-shell nanocapsules for the delivery of cancer drugs. J Colloid Interface Sci 2019; 567:171-180. [PMID: 32045739 DOI: 10.1016/j.jcis.2019.12.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/04/2019] [Accepted: 12/04/2019] [Indexed: 11/24/2022]
Abstract
Cytotoxic drugs tend to have substantial side effects on healthy tissues leading to systemic toxicity, limited tolerated doses and reduced drug efficacy. A prominent research area focuses on encapsulating cytotoxic drugs for targeted delivery to cancer tissues. However, existing carriers suffer from low drug loading levels and high drug leaching both when circulating systemically and when accumulating in non-target organs. These challenges mean that only few encapsulation technologies for delivery of cytotoxic drugs have been adopted for clinical use. Recently, we have demonstrated efficient manufacture of impermeable metal-shell/liquid core microcapsules that permit localised delivery by triggering release with ultrasound. This method has the potential to improve on existing methods for localised drug delivery because it:We demonstrate here the further miniaturization of both the emulsion droplet template and the thickness of the surrounding metal shell to the nanoscale in an attempt to take advantage of the EPR effect and the excretion of nanoparticles by the hepatobiliary system.
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Bush N, Healey A, Shah A, Box G, Kirkin V, Kotopoulis S, Kvåle S, Sontum PC, Bamber J. Therapeutic Dose Response of Acoustic Cluster Therapy in Combination With Irinotecan for the Treatment of Human Colon Cancer in Mice. Front Pharmacol 2019; 10:1299. [PMID: 31803049 PMCID: PMC6877694 DOI: 10.3389/fphar.2019.01299] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 10/10/2019] [Indexed: 12/11/2022] Open
Abstract
Introduction: Acoustic Cluster Therapy (ACT) comprises coadministration of a formulation containing microbubble-microdroplet clusters (PS101) together with a regular medicinal drug and local ultrasound (US) insonation of the targeted pathological tissue. PS101 is confined to the vascular compartment and when the clusters are exposed to regular diagnostic imaging US fields, the microdroplets undergo a phase shift to produce bubbles with a median diameter of 22 µm. Low frequency, low mechanical index US is then applied to drive oscillations of the deposited ACT bubbles to induce biomechanical effects that locally enhance extravasation, distribution, and uptake of the coadministered drug, significantly increasing its therapeutic efficacy. Methods: The therapeutic efficacy of ACT with irinotecan (60 mg/kg i.p.) was investigated using three treatment sessions given on day 0, 7, and 14 on subcutaneous human colorectal adenocarcinoma xenografts in mice. Treatment was performed with three back-to-back PS101+US administrations per session with PS101 doses ranging from 0.40-2.00 ml PS101/kg body weight (n = 8-15). To induce the phase shift, 45 s of US at 8 MHz at an MI of 0.30 was applied using a diagnostic US system; low frequency exposure consisted of 1 or 5 min at 500 kHz with an MI of 0.20. Results: ACT with irinotecan induced a strong, dose dependent increase in the therapeutic effect (R2 = 0.95). When compared to irinotecan alone, at the highest dose investigated, combination treatment induced a reduction in average normalized tumour volume from 14.6 (irinotecan), to 5.4 (ACT with irinotecan, p = 0.002) on day 27. Median survival increased from 34 days (irinotecan) to 54 (ACT with irinotecan, p = 0.002). Additionally, ACT with irinotecan induced an increase in the fraction of complete responders; from 7% to 26%. There was no significant difference in the therapeutic efficacy whether the low frequency US lasted 1 or 5 min. Furthermore, there was no significant difference between the enhancement observed in the efficacy of ACT with irinotecan when PS101+US was administered before or after irinotecan. An increase in early dropouts was observed at higher PS101 doses. Both mean tumour volume (on day 27) and median survival indicate that the PS101 dose response was linear in the range investigated.
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Affiliation(s)
- Nigel Bush
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
| | - Andrew Healey
- CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Anant Shah
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
| | - Gary Box
- CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Vladimir Kirkin
- CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | | | | | | | - Jeffrey Bamber
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
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Xia Y, Na X, Wu J, Ma G. The Horizon of the Emulsion Particulate Strategy: Engineering Hollow Particles for Biomedical Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1801159. [PMID: 30260511 DOI: 10.1002/adma.201801159] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 07/06/2018] [Indexed: 05/13/2023]
Abstract
With their hierarchical structures and the substantial surface areas, hollow particles have gained immense research interest in biomedical applications. For scalable fabrications, emulsion-based approaches have emerged as facile and versatile strategies. Here, the recent achievements in this field are unfolded via an "emulsion particulate strategy," which addresses the inherent relationship between the process control and the bioactive structures. As such, the interior architectures are manipulated by harnessing the intermediate state during the emulsion revolution (intrinsic strategy), whereas the external structures are dictated by tailoring the building blocks and solidification procedures of the Pickering emulsion (extrinsic strategy). Through integration of the intrinsic and extrinsic emulsion particulate strategy, multifunctional hollow particles demonstrate marked momentum for label-free multiplex detections, stimuli-responsive therapies, and stem cell therapies.
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Affiliation(s)
- Yufei Xia
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xiangming Na
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jie Wu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- PLA Key Laboratory of Biopharmaceutical Production & Formulation Engineering Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Guanghui Ma
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- PLA Key Laboratory of Biopharmaceutical Production & Formulation Engineering Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing, 211816, P. R. China
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Andersen KK, Healey A, Bush NL, Frijlink ME, Hoff L. A Harmonic Dual-Frequency Transducer for Acoustic Cluster Therapy. ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:2381-2390. [PMID: 31230911 DOI: 10.1016/j.ultrasmedbio.2019.04.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 03/22/2019] [Accepted: 04/07/2019] [Indexed: 06/09/2023]
Abstract
Acoustic Cluster Therapy (ACT) is a two-component formulation of commercially available microbubbles (Sonazoid; GE Healthcare, Oslo, Norway) and microdroplets (perfluorated oil) currently under development for cancer treatment. The microbubbles and microdroplets have opposite surface charges to form microbubble/microdroplet clusters, which are administered to patients together with a drug. When the clusters and drug reach the target tumour, two ultrasound (US) exposure regimes are used: First, high-frequency (>2.0 MHz) US evaporates the oil and forms ACT bubbles that lodge at the microvascular level. Second, low-frequency (0.5 MHz) US induces stable mechanical oscillations of the ACT bubbles, causing localized micro-streaming, radiation and shear forces that increase the uptake of the drugs to the target tumour. This report describes the design and testing of a dual-frequency transducer and a laboratory setup for pre-clinical in vivo studies of ACT on murine tumour models. The dual-frequency transducer utilizes the 5th harmonic (2.7 MHz) and fundamental (0.5 MHz) of a single piezoceramic disk for the high-frequency and low-frequency regimes, respectively. Two different aperture radii are used to align the high-frequency and low-frequency beam maxima, and the high-frequency -3 dB beam width diameter is 6 mm, corresponding to the largest tumour sizes we expect to treat. The low-frequency -3 dB beam width extends 6 mm. Although unconventional, the 5th harmonic exhibit a 44% efficiency and can therefore be used for transmission of acoustic energy. Moreover, both in vitro and in vivo measurements demonstrate that the 5th harmonic can be used to evaporate the microbubble/microdroplet clusters. For the in vivo measurements, we used the kidneys of non-tumour-bearing mice as tumour surrogates. Based on this, the transducer is deemed suited for pre-clinical in vivo studies of ACT and replaces a cumbersome test setup consisting of two transducers.
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Affiliation(s)
| | | | - Nigel L Bush
- Joint Department of Physics, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, UK
| | | | - Lars Hoff
- University of South-Eastern Norway, Horten, Norway
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Roovers S, Segers T, Lajoinie G, Deprez J, Versluis M, De Smedt SC, Lentacker I. The Role of Ultrasound-Driven Microbubble Dynamics in Drug Delivery: From Microbubble Fundamentals to Clinical Translation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:10173-10191. [PMID: 30653325 DOI: 10.1021/acs.langmuir.8b03779] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In the last couple of decades, ultrasound-driven microbubbles have proven excellent candidates for local drug delivery applications. Besides being useful drug carriers, microbubbles have demonstrated the ability to enhance cell and tissue permeability and, as a consequence, drug uptake herein. Notwithstanding the large amount of evidence for their therapeutic efficacy, open issues remain. Because of the vast number of ultrasound- and microbubble-related parameters that can be altered and the variability in different models, the translation from basic research to (pre)clinical studies has been hindered. This review aims at connecting the knowledge gained from fundamental microbubble studies to the therapeutic efficacy seen in in vitro and in vivo studies, with an emphasis on a better understanding of the response of a microbubble upon exposure to ultrasound and its interaction with cells and tissues. More specifically, we address the acoustic settings and microbubble-related parameters (i.e., bubble size and physicochemistry of the bubble shell) that play a key role in microbubble-cell interactions and in the associated therapeutic outcome. Additionally, new techniques that may provide additional control over the treatment, such as monodisperse microbubble formulations, tunable ultrasound scanners, and cavitation detection techniques, are discussed. An in-depth understanding of the aspects presented in this work could eventually lead the way to more efficient and tailored microbubble-assisted ultrasound therapy in the future.
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Affiliation(s)
- Silke Roovers
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Faculty of Pharmaceutical Sciences , Ghent University , Ottergemsesteenweg 460 , Ghent , Belgium
| | - Tim Segers
- Physics of Fluids Group, MESA+ Institute for Nanotechnology and Technical Medical (TechMed) Center , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - Guillaume Lajoinie
- Physics of Fluids Group, MESA+ Institute for Nanotechnology and Technical Medical (TechMed) Center , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - Joke Deprez
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Faculty of Pharmaceutical Sciences , Ghent University , Ottergemsesteenweg 460 , Ghent , Belgium
| | - Michel Versluis
- Physics of Fluids Group, MESA+ Institute for Nanotechnology and Technical Medical (TechMed) Center , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - Stefaan C De Smedt
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Faculty of Pharmaceutical Sciences , Ghent University , Ottergemsesteenweg 460 , Ghent , Belgium
| | - Ine Lentacker
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Faculty of Pharmaceutical Sciences , Ghent University , Ottergemsesteenweg 460 , Ghent , Belgium
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A versatile and robust microfluidic device for capillary-sized simple or multiple emulsions production. Biomed Microdevices 2018; 20:94. [DOI: 10.1007/s10544-018-0340-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Shen N, Lei B, Wang Y, Xu S, Liu H. Redox/ultrasound dual stimuli-responsive nanogel for precisely controllable drug release. NEW J CHEM 2018. [DOI: 10.1039/c8nj00392k] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Schematic representation of the preparation and the strategy of redox/ultrasound triggered drug release of the nanogel system.
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Affiliation(s)
- Nengwei Shen
- Key Laboratory for Advanced Materials
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
- Shanghai
- P. R. China
| | - Bin Lei
- Key Laboratory for Advanced Materials
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
- Shanghai
- P. R. China
| | - Yizhou Wang
- Key Laboratory for Advanced Materials
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
- Shanghai
- P. R. China
| | - Shouhong Xu
- Key Laboratory for Advanced Materials
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
- Shanghai
- P. R. China
| | - Honglai Liu
- Key Laboratory for Advanced Materials
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
- Shanghai
- P. R. China
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Åslund AK, Snipstad S, Healey A, Kvåle S, Torp SH, Sontum PC, Davies CDL, van Wamel A. Efficient Enhancement of Blood-Brain Barrier Permeability Using Acoustic Cluster Therapy (ACT). Theranostics 2017; 7:23-30. [PMID: 28042313 PMCID: PMC5196882 DOI: 10.7150/thno.16577] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/23/2016] [Indexed: 12/27/2022] Open
Abstract
The blood-brain barrier (BBB) is a major obstacle in drug delivery for diseases of the brain, and today there is no standardized route to surpass it. One technique to locally and transiently disrupt the BBB, is focused ultrasound in combination with gas-filled microbubbles. However, the microbubbles used are typically developed for ultrasound imaging, not BBB disruption. Here we describe efficient opening of the BBB using the promising novel Acoustic Cluster Therapy (ACT), that recently has been used in combination with Abraxane® to successfully treat subcutaneous tumors of human prostate adenocarcinoma in mice. ACT is based on the conjugation of microbubbles to liquid oil microdroplets through electrostatic interactions. Upon activation in an ultrasound field, the microdroplet phase transfers to form a larger bubble that transiently lodges in the microvasculature. Further insonation induces volume oscillations of the activated bubble, which in turn induce biomechanical effects that increase the permeability of the BBB. ACT was able to safely and temporarily permeabilize the BBB, using an acoustic power 5-10 times lower than applied for conventional microbubbles, and successfully deliver small and large molecules into the brain.
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Sonoporation with Acoustic Cluster Therapy (ACT®) induces transient tumour volume reduction in a subcutaneous xenograft model of pancreatic ductal adenocarcinoma. J Control Release 2016; 245:70-80. [PMID: 27871988 DOI: 10.1016/j.jconrel.2016.11.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/08/2016] [Accepted: 11/17/2016] [Indexed: 12/31/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancers with survival averaging only 3months if untreated following diagnosis. A major limitation in effectively treating PDAC using conventional and targeted chemotherapeutic agents, is inadequate drug delivery to the target location, predominantly due to a poorly vascularised, desmoplastic tumour microenvironment. Ultrasound in combination with ultrasound contrast agents, i.e., microbubbles, that flow through the vasculature and capillaries can be used to disrupt such mechanical barriers, potentially allowing for a greater therapeutic efficacy. This phenomenon is commonly referred to as sonoporation. In an attempt to improve the efficacy of sonoporation, novel microbubble formulations are being developed to address the limitation of commercially produced clinical diagnostic ultrasound contrast agents. In our work here we evaluate the ability of a novel formulation; namely Acoustic Cluster Therapy (ACT®) to improve the therapeutic efficacy of the chemotherapeutic agent paclitaxel, longitudinally in a xenograft model of PDAC. Results indicated that ACT® bubbles alone demonstrated no observable toxic effects, whilst ACT® in combination with paclitaxel can transiently reduce tumour volumes significantly, three days posttreatment (p=0.0347-0.0458). Quantitative 3D ultrasound validated the calliper measurements. Power Doppler ultrasound imaging indicated that ACT® in combination with paclitaxel was able to transiently sustain peak vasculature percentages as observed in the initial stages of tumour development. Nevertheless, there was no significant difference in tumour vasculature percentage at the end of treatment. The high vascular percentage correlated to the transient decrease and overall inhibition of the tumour volumes. In conclusion, ACT® improves the therapeutic efficacy of paclitaxel in a PDAC xenograft model allowing for transient tumour volume reduction and sustained tumour vasculature percentage.
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Myhre O, Bjørgan M, Grant D, Hustvedt SO, Sontum PC, Dirven H. Safety assessment in rats and dogs of Acoustic Cluster Therapy, a novel concept for ultrasound mediated, targeted drug delivery. Pharmacol Res Perspect 2016; 4:e00274. [PMID: 28097007 PMCID: PMC5226284 DOI: 10.1002/prp2.274] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 10/10/2016] [Indexed: 01/29/2023] Open
Abstract
Acoustic Cluster Therapy (ACT) represents a novel concept for targeted drug delivery. Ultrasound is applied to activate intravenously administered free-flowing clusters of microbubbles and microdroplets within the target pathology, depositing 20-30 μm large bubbles in the microvasculature for 5-10 min. Further application of ultrasound induces biomechanical effects which increase vascular permeability and enhance localized extravasation of coadministered drugs. Herein we report investigations done to assess the preclinical safety of ACT, using doses up to 1 mL/kg (3 μL perfluoromethyl-cyclopentane/kg). In dogs, half the animals were exposed to ultrasound activation in the heart for 1 min, no ultrasound was applied in the other half. Posttreatment observation time was 24 h. Clinical signs, ophthalmoscopy, clinical pathology, macro-, and microscopy were used as endpoints. No differences between groups with and without ultrasound activation were observed. Short-lasting leukopenia and thrombocytopenia, possibly secondary to a slight and short-lasting increase in plasma histamine and complement split products, were the only effects noted. In rats ACT was activated in the liver for 5 min. Histopathology and clinical chemistry parameters remained unchanged. Lastly, rats were treated with ACT activated in the heart and thereafter placed on a rotarod for evaluation of motor coordination. No differences were observed between animals treated with ACT and controls. In conclusion, ACT appeared safe at dose-levels up to 1 mL/kg and with activation either in the heart or the liver. These results, together with positive efficacy data upon coinjection with cytotoxic compounds encourage further preclinical safety studies with the objective of entering subsequent clinical trials.
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Affiliation(s)
- Oddvar Myhre
- Norwegian Institute of Public Health Oslo Norway
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van Wamel A, Sontum PC, Healey A, Kvåle S, Bush N, Bamber J, de Lange Davies C. Acoustic Cluster Therapy (ACT) enhances the therapeutic efficacy of paclitaxel and Abraxane® for treatment of human prostate adenocarcinoma in mice. J Control Release 2016; 236:15-21. [PMID: 27297780 DOI: 10.1016/j.jconrel.2016.06.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/07/2016] [Accepted: 06/09/2016] [Indexed: 01/05/2023]
Abstract
Acoustic cluster therapy (ACT) is a novel approach for ultrasound mediated, targeted drug delivery. In the current study, we have investigated ACT in combination with paclitaxel and Abraxane® for treatment of a subcutaneous human prostate adenocarcinoma (PC3) in mice. In combination with paclitaxel (12mg/kg given i.p.), ACT induced a strong increase in therapeutic efficacy; 120days after study start, 42% of the animals were in stable, complete remission vs. 0% for the paclitaxel only group and the median survival was increased by 86%. In combination with Abraxane® (12mg paclitaxel/kg given i.v.), ACT induced a strong increase in the therapeutic efficacy; 60days after study start 100% of the animals were in stable, remission vs. 0% for the Abraxane® only group, 120days after study start 67% of the animals were in stable, complete remission vs. 0% for the Abraxane® only group. For the ACT+Abraxane group 100% of the animals were alive after 120days vs. 0% for the Abraxane® only group. Proof of concept for Acoustic Cluster Therapy has been demonstrated; ACT markedly increases the therapeutic efficacy of both paclitaxel and Abraxane® for treatment of human prostate adenocarcinoma in mice.
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Affiliation(s)
- Annemieke van Wamel
- Dept. of Physics, NTNU, Norwegian University of Science and Technology, Trondheim, Norway.
| | | | | | | | - Nigel Bush
- Joint Dept. of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, UK
| | - Jeffrey Bamber
- Joint Dept. of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, UK
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Healey AJ, Sontum PC, Kvåle S, Eriksen M, Bendiksen R, Tornes A, Østensen J. Acoustic Cluster Therapy: In Vitro and Ex Vivo Measurement of Activated Bubble Size Distribution and Temporal Dynamics. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:1145-1166. [PMID: 26831341 DOI: 10.1016/j.ultrasmedbio.2015.12.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 12/07/2015] [Accepted: 12/14/2015] [Indexed: 06/05/2023]
Abstract
Acoustic cluster technology (ACT) is a two-component, microparticle formulation platform being developed for ultrasound-mediated drug delivery. Sonazoid microbubbles, which have a negative surface charge, are mixed with micron-sized perfluoromethylcyclopentane droplets stabilized with a positively charged surface membrane to form microbubble/microdroplet clusters. On exposure to ultrasound, the oil undergoes a phase change to the gaseous state, generating 20- to 40-μm ACT bubbles. An acoustic transmission technique is used to measure absorption and velocity dispersion of the ACT bubbles. An inversion technique computes bubble size population with temporal resolution of seconds. Bubble populations are measured both in vitro and in vivo after activation within the cardiac chambers of a dog model, with catheter-based flow through an extracorporeal measurement flow chamber. Volume-weighted mean diameter in arterial blood after activation in the left ventricle was 22 μm, with no bubbles >44 μm in diameter. After intravenous administration, 24.4% of the oil is activated in the cardiac chambers.
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Wamel AV, Healey A, Sontum PC, Kvåle S, Bush N, Bamber J, de Lange Davies C. Acoustic Cluster Therapy (ACT) - pre-clinical proof of principle for local drug delivery and enhanced uptake. J Control Release 2016; 224:158-164. [PMID: 26774223 DOI: 10.1016/j.jconrel.2016.01.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/11/2016] [Accepted: 01/12/2016] [Indexed: 01/05/2023]
Abstract
Proof of principle for local drug delivery with Acoustic Cluster Therapy (ACT) was demonstrated in a human prostate adenocarcinoma growing in athymic mice, using near infrared (NIR) dyes as model molecules. A dispersion of negatively charged microbubble/positively charged microdroplet clusters are injected i.v., activated within the target pathology by diagnostic ultrasound (US), undergo an ensuing liquid-to-gas phase shift and transiently deposit 20-30μm large bubbles in the microvasculature, occluding blood flow for ~5-10min. Further application of low frequency US induces biomechanical effects that increase the vascular permeability, leading to a locally enhanced extravasation of components from the vascular compartment (e.g., released or co-administered drugs). Results demonstrated deposition of activated bubbles in tumor vasculature. Following ACT treatment, a significant and tumor specific increase in the uptake of a co-administered macromolecular NIR dye was shown. In addition, ACT compound loaded with a lipophilic NIR dye to the microdroplet component was shown to facilitate local release and tumor specific uptake. Whereas the mechanisms behind the observed increased and tumor specific uptake are not fully elucidated, it is demonstrated that the ACT concept can be applied as a versatile technique for targeted drug delivery.
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