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Zhu H, Zhou X, Ju R, Leng J, Tian J, Qu S, Tao S, Lyu Y, Zhang N. Challenges in clinical practice, biological mechanism and prospects of physical ablation therapy for COPD. Life Sci 2024; 349:122718. [PMID: 38754815 DOI: 10.1016/j.lfs.2024.122718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 05/03/2024] [Accepted: 05/11/2024] [Indexed: 05/18/2024]
Abstract
Chronic obstructive pulmonary disease (COPD) is projected to become the third leading cause of death globally by 2030. Despite the limited treatment options available for advanced COPD, which are mostly restricted to costly lung transplants, physical ablation therapy offers promising alternatives. This technique focuses on ablating lesioned airway epithelium, reducing secretions and obstructions, and promoting normal epithelial regeneration, demonstrating significant therapeutic potential. Physical ablation therapy primarily involves thermal steam ablation, cryoablation, targeted lung denervation, and high-voltage pulsed electric field ablation. These methods help transform the hypersecretory phenotype, alleviate airway inflammation, and decrease the volume of emphysematous lung segments by targeting goblet cells and damaged lung areas. Compared to traditional treatments, endoscopic physical ablation offers fewer injuries, quicker recovery, and enhanced safety. However, its application in COPD remains limited due to inconsistent clinical outcomes, a lack of well-understood mechanisms, and the absence of standardized guidelines. This review begins by exploring the development of these ablation techniques and their current clinical uses in COPD treatment. It then delves into the therapeutic effects reported in recent clinical studies and discusses the underlying mechanisms. Finally, the review assesses the future prospects and challenges of employing ablation technology in COPD clinical practice, aiming to provide a practical reference and a theoretical basis for its use and inspire further research.
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Affiliation(s)
- Haoyang Zhu
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Department of Anesthesiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Xiaoyu Zhou
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Ran Ju
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Jing Leng
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Jiawei Tian
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China; Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Shenao Qu
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Shiran Tao
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Yi Lyu
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China; Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
| | - Nana Zhang
- Institute of Regenerative and Reconstructive Medicine, Med-X Institute, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China; Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China.
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Fesmire CC, Williamson RH, Petrella RA, Kaufman JD, Topasna N, Sano MB. Integrated Time Nanosecond Pulse Irreversible Electroporation (INSPIRE): Assessment of Dose, Temperature, and Voltage on Experimental and Clinical Treatment Outcomes. IEEE Trans Biomed Eng 2024; 71:1511-1520. [PMID: 38145519 PMCID: PMC11035095 DOI: 10.1109/tbme.2023.3340718] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
OBJECTIVE This study sought to investigate a novel strategy using temperature-controlled delivery of nanosecond pulsed electric fields as an alternative to the 50-100 microsecond pulses used for irreversible electroporation. METHODS INSPIRE treatments were carried out at two temperatures in 3D tumor models using doses between 0.001 s and 0.1 s. The resulting treatment zones were quantified using viability staining and lethal electric field intensities were determined numerically. Computational modeling was then used to determine parameters necessary for INSPIRE treatments to achieve equivalent treatment zones to clinical electroporation treatments and evaluate the potential for these treatments to induce deleterious thermal damage. RESULTS Lethal thresholds between 1109 and 709 V/cm were found for nominal 0.01 s treatments with pulses between 350 ns and 2000 ns at physiological temperatures. Further increases in dose resulted in significant decreases in lethal thresholds. Given these experimental results, treatment zones comparable to clinical electroporation are possible by increasing the dose and voltage used with nanosecond duration pulses. Temperature-controlled simulations indicate minimal thermal cell death while achieving equivalent treatment volumes to clinical electroporation. CONCLUSION Nanosecond electrical pulses can achieve comparable outcomes to traditional electroporation provided sufficient electrical doses or voltages are applied. The use of temperature-controlled delivery may minimize thermal damage during treatment. SIGNIFICANCE Intense muscle stimulation and the need for cardiac gating have limited irreversible electroporation. Nanosecond pulses can alleviate these challenges, but traditionally have produced significantly smaller treatment zones. This study suggests that larger ablation volumes may be possible with the INSPIRE approach and that future in vivo studies are warranted.
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de Caro A, Talmont F, Rols MP, Golzio M, Kolosnjaj-Tabi J. Therapeutic perspectives of high pulse repetition rate electroporation. Bioelectrochemistry 2024; 156:108629. [PMID: 38159429 DOI: 10.1016/j.bioelechem.2023.108629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 12/15/2023] [Accepted: 12/16/2023] [Indexed: 01/03/2024]
Abstract
Electroporation, a technique that uses electrical pulses to temporarily or permanently destabilize cell membranes, is increasingly used in cancer treatment, gene therapy, and cardiac tissue ablation. Although the technique is efficient, patients report discomfort and pain. Current strategies that aim to minimize pain and muscle contraction rely on the use of pharmacological agents. Nevertheless, technical improvements might be a valuable tool to minimize adverse events, which occur during the application of standard electroporation protocols. One recent technological strategy involves the use of high pulse repetition rate. The emerging technique, also referred as "high frequency" electroporation, employs short (micro to nanosecond) mono or bipolar pulses at repetition rate ranging from a few kHz to a few MHz. This review provides an overview of the historical background of electric field use and its development in therapies over time. With the aim to understand the rationale for novel electroporation protocols development, we briefly describe the physiological background of neuromuscular stimulation and pain caused by exposure to pulsed electric fields. Then, we summarize the current knowledge on electroporation protocols based on high pulse repetition rates. The advantages and limitations of these protocols are described from the perspective of their therapeutic application.
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Affiliation(s)
- Alexia de Caro
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Franck Talmont
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Marie-Pierre Rols
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Muriel Golzio
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France.
| | - Jelena Kolosnjaj-Tabi
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France.
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Vrabel MR, Fesmire CC, Rich MJ, Kobrin RL, Sano MB, Zaharoff DA. A novel in vitro model of clinical cryoablation to investigate the transition zone for focal tumor ablation. Cryobiology 2024; 114:104844. [PMID: 38171448 DOI: 10.1016/j.cryobiol.2023.104844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 12/28/2023] [Accepted: 12/28/2023] [Indexed: 01/05/2024]
Abstract
Cryoablation (CA) of solid tumors is highly effective at reducing tumor burden and eliminating small, early stage tumors. However, complete ablation is difficult to achieve and cancer recurrence is a significant barrier to treatment of larger tumors compared to resection. In this study, we explored the relationship between temperature, ice growth, and cell death using a novel in vitro model of clinical CA with the Visual-ICE (Boston Scientific) system, a clinically approved and widely utilized device. We found that increasing the duration of freezing from 1 to 2 min increased ice radius from 3.44 ± 0.13 mm to 5.29 ± 0.16 mm, and decreased the minimum temperature achieved from -22.8 ± 1.3 °C to -45.5 ± 7.9 °C. Furthermore, an additional minute of freezing increased the amount of cell death within a 5 mm radius from 42.5 ± 8.9% to 84.8 ± 1.1%. Freezing at 100% intensity leads to faster temperature drops and a higher level of cell death in the TRAMP-C2 mouse prostate cancer cell line, while lower intensities are useful for slow freezing, but result in less cell death. The width of transition zone between live and dead cells decreased by 0.4 ± 0.2 mm, increasing from one to two cycles of freeze/thaw cycles at 100% intensity. HMGB-1 levels significantly increased with 3 cycles of freeze/thaw compared to the standard 2 cycles. Overall, a longer freezing duration, higher freezing intensity, and more freeze thaw cycles led to higher levels of cancer cell death and smaller transition zones. These results have the potential to inform future preclinical research and to improve therapeutic combinations with CA.
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Affiliation(s)
- Maura R Vrabel
- Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina-Chapel Hill, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA.
| | - Christopher C Fesmire
- Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina-Chapel Hill, Raleigh, NC, USA.
| | - Matthew J Rich
- Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina-Chapel Hill, Raleigh, NC, USA.
| | - Robert L Kobrin
- Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina-Chapel Hill, Raleigh, NC, USA.
| | - Michael B Sano
- Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina-Chapel Hill, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA; Department of Molecular and Biomedical Sciences, North Carolina State University, Raleigh, NC, USA.
| | - David A Zaharoff
- Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina-Chapel Hill, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA.
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Fesmire CC, Peal B, Ruff J, Moyer E, McParland TJ, Derks K, O’Neil E, Emke C, Johnson B, Ghosh S, Petrella RA, DeWitt MR, Prange T, Fogle C, Sano MB. Investigation of integrated time nanosecond pulse irreversible electroporation against spontaneous equine melanoma. Front Vet Sci 2024; 11:1232650. [PMID: 38352036 PMCID: PMC10861690 DOI: 10.3389/fvets.2024.1232650] [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: 05/31/2023] [Accepted: 01/10/2024] [Indexed: 02/16/2024] Open
Abstract
Introduction Integrated time nanosecond pulse irreversible electroporation (INSPIRE) is a novel tumor ablation modality that employs high voltage, alternating polarity waveforms to induce cell death in a well-defined volume while sparing the underlying tissue. This study aimed to demonstrate the in vivo efficacy of INSPIRE against spontaneous melanoma in standing, awake horses. Methods A custom applicator and a pulse generation system were utilized in a pilot study to treat horses presenting with spontaneous melanoma. INSPIRE treatments were administered to 32 tumors across 6 horses and an additional 13 tumors were followed to act as untreated controls. Tumors were tracked over a 43-85 day period following a single INSPIRE treatment. Pulse widths of 500ns and 2000ns with voltages between 1000 V and 2000 V were investigated to determine the effect of these variables on treatment outcomes. Results Treatments administered at the lowest voltage (1000 V) reduced tumor volumes by 11 to 15%. Higher voltage (2000 V) treatments reduced tumor volumes by 84 to 88% and eliminated 33% and 80% of tumors when 500 ns and 2000 ns pulses were administered, respectively. Discussion Promising results were achieved without the use of chemotherapeutics, the use of general anesthesia, or the need for surgical resection in regions which are challenging to keep sterile. This novel therapeutic approach has the potential to expand the role of pulsed electric fields in veterinary patients, especially when general anesthesia is contraindicated, and warrants future studies to demonstrate the efficacy of INSPIRE as a solid tumor treatment.
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Affiliation(s)
- Chris C. Fesmire
- Bioelectricity Lab, UNC/NCSU Joint Department of Biomedical Engineering, Raleigh, NC, United States
| | - Bridgette Peal
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Jennifer Ruff
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Elizabeth Moyer
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Thomas J. McParland
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Kobi Derks
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Erin O’Neil
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Carrie Emke
- Clinical Studies Core, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Brianna Johnson
- Clinical Studies Core, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Shatorupa Ghosh
- Bioelectricity Lab, UNC/NCSU Joint Department of Biomedical Engineering, Raleigh, NC, United States
| | - Ross A. Petrella
- Bioelectricity Lab, UNC/NCSU Joint Department of Biomedical Engineering, Raleigh, NC, United States
| | - Matthew R. DeWitt
- Bioelectricity Lab, UNC/NCSU Joint Department of Biomedical Engineering, Raleigh, NC, United States
| | - Timo Prange
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Callie Fogle
- Department of Clinical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
| | - Michael B. Sano
- Bioelectricity Lab, UNC/NCSU Joint Department of Biomedical Engineering, Raleigh, NC, United States
- Department of Molecular Biomedical Sciences, NC State College of Veterinary Medicine, Raleigh, NC, United States
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Agnass P, Rodermond HM, van Veldhuisen E, Vogel JA, Ten Cate R, van Lienden KP, van Gulik TM, Franken NAP, Oei AL, Kok HP, Besselink MG, Crezee J. Quantitative analysis of contribution of mild and moderate hyperthermia to thermal ablation and sensitization of irreversible electroporation of pancreatic cancer cells. J Therm Biol 2023; 115:103619. [PMID: 37437370 DOI: 10.1016/j.jtherbio.2023.103619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/09/2023] [Accepted: 05/30/2023] [Indexed: 07/14/2023]
Abstract
INTRODUCTION Irreversible electroporation (IRE) is an ablation modality that applies short, high-voltage electric pulses to unresectable cancers. Although considered a non-thermal technique, temperatures do increase during IRE. This temperature rise sensitizes tumor cells for electroporation as well as inducing partial direct thermal ablation. AIM To evaluate the extent to which mild and moderate hyperthermia enhance electroporation effects, and to establish and validate in a pilot study cell viability models (CVM) as function of both electroporation parameters and temperature in a relevant pancreatic cancer cell line. METHODS Several IRE-protocols were applied at different well-controlled temperature levels (37 °C ≤ T ≤ 46 °C) to evaluate temperature dependent cell viability at enhanced temperatures in comparison to cell viability at T = 37 °C. A realistic sigmoid CVM function was used based on thermal damage probability with Arrhenius Equation and cumulative equivalent minutes at 43 °C (CEM43°C) as arguments, and fitted to the experimental data using "Non-linear-least-squares"-analysis. RESULTS Mild (40 °C) and moderate (46 °C) hyperthermic temperatures boosted cell ablation with up to 30% and 95%, respectively, mainly around the IRE threshold Eth,50% electric-field strength that results in 50% cell viability. The CVM was successfully fitted to the experimental data. CONCLUSION Both mild- and moderate hyperthermia significantly boost the electroporation effect at electric-field strengths neighboring Eth,50%. Inclusion of temperature in the newly developed CVM correctly predicted both temperature-dependent cell viability and thermal ablation for pancreatic cancer cells exposed to a relevant range of electric-field strengths/pulse parameters and mild moderate hyperthermic temperatures.
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Affiliation(s)
- P Agnass
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands.
| | - H M Rodermond
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - E van Veldhuisen
- Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands.
| | - J A Vogel
- Amsterdam UMC Location University of Amsterdam, Gastroenterology & Hepatology, Meibergdreef 9, Amsterdam, the Netherlands.
| | - R Ten Cate
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - K P van Lienden
- Department of Intervention Radiology, St. Antonius Hospital, Nieuwegein, the Netherlands.
| | - T M van Gulik
- Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands.
| | - N A P Franken
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - A L Oei
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - H P Kok
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Cancer Center Amsterdam, Treatment and Quality of Life, Cancer Biology and Immunology, Amsterdam, the Netherlands.
| | - M G Besselink
- Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands.
| | - J Crezee
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Cancer Center Amsterdam, Treatment and Quality of Life, Cancer Biology and Immunology, Amsterdam, the Netherlands.
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Müller WA, Sarkis JR, Marczak LDF, Muniz AR. Molecular dynamics insights on temperature and pressure effects on electroporation. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:184049. [PMID: 36113558 DOI: 10.1016/j.bbamem.2022.184049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 09/02/2022] [Accepted: 09/08/2022] [Indexed: 06/15/2023]
Abstract
Electroporation is a cell-level phenomenon caused by an ionic imbalance in the membrane, being of great relevance in various fields of knowledge. A dependence of the pore formation kinetics on the environmental conditions (temperature and pressure) of the cell membrane has already been reported, but further clarification regarding how these variables affect the pore formation/resealing dynamics and the transport of molecules through the membrane is still lacking. The objective of the present study was to investigate the temperature (288-348 K) and pressure (1-5000 atm) effects on the electroporation kinetics using coarse-grained molecular dynamics simulations. Results shown that the time for pore formation and resealing increased with pressure and decreased with temperature, whereas the maximum pore radius increased with temperature and decreased with pressure. This behavior influenced the ion migration through the bilayer, and the higher ionic mobility was obtained in the 288 K/1000 atm simulations, i.e., a combination of low temperature and (not excessively) high pressure. These results were used to discuss some experimental observations regarding the extraction of intracellular compounds applying this technique. This study contributes to a better understanding of electroporation under different thermodynamic conditions and to an optimal selection of processing parameters in practical applications which exploit this phenomenon.
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Affiliation(s)
- Wagner Augusto Müller
- Universidade Federal do Rio Grande do Sul (UFRGS), Department of Chemical Engineering, Porto Alegre, RS, Brazil
| | - Júlia Ribeiro Sarkis
- Universidade Federal do Rio Grande do Sul (UFRGS), Department of Chemical Engineering, Porto Alegre, RS, Brazil
| | | | - André Rodrigues Muniz
- Universidade Federal do Rio Grande do Sul (UFRGS), Department of Chemical Engineering, Porto Alegre, RS, Brazil.
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Aycock KN, Vadlamani RA, Jacobs EJ, Imran KM, Verbridge S, Allen IC, Manuchehrabadi N, Davalos RV. Experimental and Numerical Investigation of Parameters Affecting High-frequency Irreversible Electroporation for Prostate Cancer Ablation. J Biomech Eng 2022; 144:1131491. [PMID: 35044426 DOI: 10.1115/1.4053595] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Indexed: 11/09/2022]
Abstract
While the primary goal of focal therapy for prostate cancer (PCa) is conserving patient quality of life by reducing oncological burden, available modalities use thermal energy or whole-gland radiation which can damage critical neurovascular structures within the prostate and increase risk of genitourinary dysfunction. High-frequency irreversible electroporation (H-FIRE) is a promising alternative ablation modality that utilizes bursts of pulsed electric fields (PEFs) to destroy aberrant cells via targeted membrane damage. Due to its non-thermal mechanism, H-FIRE offers several advantages over state-of-the-art treatments, but waveforms have not been optimized for treatment of PCa. In this study, we characterize lethal electric field thresholds (EFTs) for H-FIRE waveforms with three different pulse widths as well as three interpulse delays in vitro and compare them to conventional IRE. Experiments were performed in non-neoplastic and malignant prostate cells to determine the effect of waveforms on both targeted (malignant) and adjacent (non-neoplastic) tissue. A numerical modeling approach was developed to estimate the clinical effects of each waveform including extent of non-thermal ablation, undesired thermal damage, and nerve excitation. Our findings indicate that H-FIRE waveforms with pulse durations of 5 and 10 µs provide large ablations comparable to IRE with tolerable levels of thermal damage and minimized muscle contractions. Lower duration (2 µs) H-FIRE waveforms exhibit the least amount of muscle contractions but require increased voltages which may be accompanied by unwanted thermal damage.
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Affiliation(s)
- Kenneth N Aycock
- Virginia Tech, Department of Biomedical Engineering and Mechanics, 325 Stanger St, Blacksburg, VA 24061
| | - Ram Anand Vadlamani
- Virginia Tech, Department of Biomedical Engineering and Mechanics, 325 Stanger St, Blacksburg, VA 24061
| | - Edward J Jacobs
- Virginia Tech, Department of Biomedical Engineering and Mechanics, 325 Stanger St, Blacksburg, VA 24061
| | - Khan Mohammad Imran
- Virginia-Maryland College of Veterinary Medicine, Department of Biomedical Sciences and Pathobiology, 205 Duck Pond Dr, Blacksburg, VA 24061
| | - Scott Verbridge
- Virginia Tech, Department of Biomedical Engineering and Mechanics, 325 Stanger St, Blacksburg, VA 24061
| | - Irving C Allen
- Virginia-Maryland College of Veterinary Medicine, Department of Biomedical Sciences and Pathobiology, 205 Duck Pond Dr, Blacksburg, VA 24061
| | | | - Rafael V Davalos
- Virginia Tech, Department of Biomedical Engineering and Mechanics, 325 Stanger St, Blacksburg, VA 24061
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Petrella RA, Levit SL, Fesmire CC, Tang C, Sano MB. Polymer Nanoparticles Enhance Irreversible Electroporation In Vitro. IEEE Trans Biomed Eng 2022; 69:2353-2362. [PMID: 35025737 DOI: 10.1109/tbme.2022.3143084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Expanding the volume of an irreversible electroporation treatment typically necessitates an increase in pulse voltage, number, duration, or repetition. This study investigates the addition of polyethylenimine nanoparticles (PEI-NP) to pulsed electric field treatments, determining their combined effect on ablation size and voltages. U118 cells in an in vitro 3D cell culture model were treated with one of three pulse parameters (with and without PEI-NPs) which are representative of irreversible electroporation (IRE), high frequency irreversible electroporation (H-FIRE), or nanosecond pulsed electric fields (nsPEF). The size of the ablations were compared and mapped onto an electric field model to describe the electric field required to induce cell death. Analysis was conducted to determine the role of PEI-NPs in altering media conductivity, the potential for PEI-NP degradation following pulsed electric field treatment, and PEI-NP uptake. Results show there was a statistically significant increase in ablation diameter for IRE and H-FIRE pulses with PEI-NPs. There was no increase in ablation size for nsPEF with PEI-NPs. This all occurs with no change in cell media conductivity, no observable degradation of PEI-NPs, and moderate particle uptake. These results demonstrate the synergy of a combined cationic polymer nanoparticle and pulsed electric field treatment for the ablation of cancer cells. These results set the foundation for polymer nanoparticles engineered specifically for irreversible electroporation.
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Jenkins EPW, Finch A, Gerigk M, Triantis IF, Watts C, Malliaras GG. Electrotherapies for Glioblastoma. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100978. [PMID: 34292672 PMCID: PMC8456216 DOI: 10.1002/advs.202100978] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/20/2021] [Indexed: 05/08/2023]
Abstract
Non-thermal, intermediate frequency (100-500 kHz) electrotherapies present a unique therapeutic strategy to treat malignant neoplasms. Here, pulsed electric fields (PEFs) which induce reversible or irreversible electroporation (IRE) and tumour-treating fields (TTFs) are reviewed highlighting the foundations, advances, and considerations of each method when applied to glioblastoma (GBM). Several biological aspects of GBM that contribute to treatment complexity (heterogeneity, recurrence, resistance, and blood-brain barrier(BBB)) and electrophysiological traits which are suggested to promote glioma progression are described. Particularly, the biological responses at the cellular and molecular level to specific parameters of the electrical stimuli are discussed offering ways to compare these parameters despite the lack of a universally adopted physical description. Reviewing the literature, a disconnect is found between electrotherapy techniques and how they target the biological complexities of GBM that make treatment difficult in the first place. An attempt is made to bridge the interdisciplinary gap by mapping biological characteristics to different methods of electrotherapy, suggesting important future research topics and directions in both understanding and treating GBM. To the authors' knowledge, this is the first paper that attempts an in-tandem assessment of the biological effects of different aspects of intermediate frequency electrotherapy methods, thus offering possible strategies toward GBM treatment.
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Affiliation(s)
- Elise P. W. Jenkins
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
| | - Alina Finch
- Institute of Cancer and Genomic ScienceUniversity of BirminghamBirminghamB15 2TTUK
| | - Magda Gerigk
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
| | - Iasonas F. Triantis
- Department of Electrical and Electronic EngineeringCity, University of LondonLondonEC1V 0HBUK
| | - Colin Watts
- Institute of Cancer and Genomic ScienceUniversity of BirminghamBirminghamB15 2TTUK
| | - George G. Malliaras
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
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Dynamic Electroporation Model Evaluation on Rabbit Tissues. Ann Biomed Eng 2021; 49:2503-2512. [PMID: 34169397 PMCID: PMC8224995 DOI: 10.1007/s10439-021-02816-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/16/2021] [Indexed: 11/27/2022]
Abstract
Biological electroporation is a process of opening pores in the cell membrane when exposed to intense electric fields. This work provides results for validation of a dynamic model of electroporation on biological tissues. Computational simulations were carried out and results for the electrical current through the tissue and increase of the tissue temperature were compared to experimental results. Two calculation methods were used: Equivalent Circuit Method and Finite Element Method. With Equivalent Circuit Method the dielectric dispersion present in biological tissues was included. Liver, kidney and heart of rabbit were used in the experiments. Voltage pulse protocols and voltage ramps were applied using stainless steel needles electrodes. There is good agreement between the simulated and experimental results with mean errors below 15%, with the simulated results within the experimental standard deviation. Only for the protocol with fundamental frequency of 50 kHz, the simulation performed by the Finite Element Method using a commercial software did not correctly represent the current, with errors reaching 50%. The justification for the error found is due to the dielectric dispersion that was not included in this simulator.
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Comparison between high-frequency irreversible electroporation and irreversible electroporation ablation of small swine liver: follow-up of DCE-MRI and pathological observations. Chin Med J (Engl) 2021; 134:2081-2090. [PMID: 34172620 PMCID: PMC8439989 DOI: 10.1097/cm9.0000000000001663] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background: High-frequency irreversible electroporation (H-FIRE) is a novel, next-generation nanoknife technology with the advantage of relieving irreversible electroporation (IRE)-induced muscle contractions. However, the difference between IRE and H-FIRE with distinct ablation parameters was not clearly defined. This study aimed to compare the efficacy of the two treatments in vivo. Methods: Ten Bama miniature swine were divided into two group: five in the 1-day group and five in the 7-day group. The efficacy of IRE and H-FIRE ablation was compared by volume transfer constant (Krans), rate constant (Kep) and extravascular extracellular volume fraction (Ve) value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), size of the ablation zone, and histologic analysis. Each animal underwent the IRE and H-FIRE. Temperatures of the electrodes were measured during ablation. DCE-MRI images were obtained 1, 4, and 7 days after ablation in the 7-day group. All animals in the two groups were euthanized 1 day or 7 days after ablation, and subsequently, IRE and H-FIRE treated liver tissues were collected for histological examination. Student's t test or Mann-Whitney U test was applied for comparing any two groups. One-way analysis of variance (ANOVA) test and Welch's ANOVA test followed by Holm-Sidak's multiple comparisons test, one-way ANOVA with repeated measures followed by Bonferroni test, or Kruskal-Wallis H test followed by Dunn's multiple comparison test was used for multiple group comparisons and post hoc analyses. Pearson correlation coefficient test was conducted to analyze the relationship between two variables. Results: Higher Ve was seen in IRE zone than in H-FIRE zone (0.14 ± 0.02 vs. 0.08 ± 0.05, t = 2.408, P = 0.043) on day 4, but no significant difference was seen in Ktrans or Kep between IRE and H-FIRE zones at all time points (all P > 0.05). For IRE zone, the greatest Ktrans was seen on day 7, which was significantly higher than that on day 1 (P = 0.033). The ablation zone size of H-FIRE was significantly larger than IRE 1 day (4.74 ± 0.88 cm2vs. 3.20 ± 0.77 cm2, t = 3.241, P = 0.009) and 4 days (2.22 ± 0.83 cm2vs. 1.30 ± 0.50 cm2, t = 2.343, P = 0.041) after treatment. Apoptotic index (0.05 ± 0.02 vs. 0.73 ± 0.06 vs. 0.68 ± 0.07, F = 241.300, P < 0.001) and heat shock protein 70 (HSP70) (0.03 ± 0.01 vs. 0.46 ± 0.09 vs. and 0.42 ± 0.07, F = 64.490, P < 0.001) were significantly different between the untreated, IRE and H-FIRE zones, but no significant difference was seen in apoptotic index or HSP70 between IRE and H-FIRE zone (both P > 0.05). Electrode temperature variations were not significantly different between the two zones (18.00 ± 3.77°C vs. 16.20 ± 7.45°C, t = 0.682, P = 0.504). The Ktrans value (r = 0.940, P = 0.017) and the Kep value (r = 0.895, P = 0.040) of the H-FIRE zone were positively correlated with the number of hepatocytes in the ablation zone. Conclusions: H-FIRE showed a comparable ablation effect to IRE. DCE-MRI has the potential to monitor the changes of H-FIRE ablation zone.
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Irreversible Electroporation Enhanced by Radiofrequency Ablation: An In Vitro and Computational Study in a 3D Liver Tumor Model. Ann Biomed Eng 2021; 49:2126-2138. [PMID: 33594637 DOI: 10.1007/s10439-021-02734-x] [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] [Received: 10/21/2020] [Accepted: 01/15/2021] [Indexed: 12/24/2022]
Abstract
In the present study, we used a computational and experimental study in a 3D liver tumor model (LTM) to explore the tumor ablation enhancement of irreversible electroporation (IRE) by pre-heating with radiofrequency ablation (RFA) and elucidate the mechanism whereby this enhancement occurs. Three ablation protocols, including IRE alone, RFA45 → IRE (with the pre-heating temperature of 45 °C), and RFA60 → IRE (with the pre-heating temperature of 60 °C) were investigated. Both the thermal conductivity and electrical conductivity of the 3D LTM were characterized with the change in the pre-heating temperature. The results showed, compared to IRE alone, a significant increase in the tumor ablation volume (19.59 [Formula: see text] 0.61 vs. 15.29 ± 0.61 mm3, p = 0.002 and 22.87 [Formula: see text] 0.35 vs. 15.29 ± 0.61 mm3, p < 0.001) was observed with both RFA45 → IRE and RFA60 → IRE, leading to a decrease in lethal electric filed strength (8 and 17%, correspondingly). The mechanism can be attributed to the change of cell microenvironment by pre-heating and/or a synergistic effect of RFA and IRE. The proposed enhancing method might contribute to the improvement of interventional oncology in the treatment of large tumors close to critical organs (e.g., large blood vessels and bile ducts).
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Rojo RD, Perez JVD, Damasco JA, Yu G, Lin SC, Heralde FM, Novone NM, Santos EB, Lin SH, Melancon MP. Combinatorial effect of radium-223 and irreversible electroporation on prostate cancer bone metastasis in mice. Int J Hyperthermia 2021; 38:650-662. [PMID: 33882773 PMCID: PMC8495630 DOI: 10.1080/02656736.2021.1914873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Metastatic prostate cancer in bone is difficult to treat as the tumor cells are relatively resistant to hormonal or chemotherapies when compared to primary prostate cancer. Irreversible electroporation (IRE) is a minimally invasive ablation procedure that has potential applications in the management of prostate cancer in bone. However, a common limitation of IRE is tumor recurrence, which arises from incomplete ablation that allows remaining cancer cells to proliferate. In this study, we combined IRE with radium-223 (Ra-223), a bone-seeking radionuclide that emits short track length alpha particles and thus is associated with reduced damage to the bone marrow and evaluated the impact of the combination treatment on bone-forming prostate cancer tumors. METHODS The antitumor activity of IRE and Ra-223 as single agents and in combination was tested in vitro against three bone morphogenetic protein 4 (BMP4)-expressing prostate cancer cell lines (C4-2B-BMP4, Myc-CaP-BMP4, and TRAMP-C2-BMP4). Similar evaluation was performed in vivo using a bone-forming C4-2B-BMP4 tumor model in nude mice. RESULTS IRE and Ra-223 as monotherapy inhibited prostate cancer cell proliferation in vitro, and their combination resulted in significant reduction in cell viability compared to monotherapy. In vivo evaluation revealed that IRE with single-dose administration of Ra-233, compared to IRE alone, reduced the rate of tumor recurrence by 40% following initial apparent complete ablation and decreased the rate of proliferation of incompletely ablated tumor as quantified in Ki-67 staining (53.58 ± 16.0% for IRE vs. 20.12 ± 1.63%; for IRE plus Ra-223; p = 0.004). Histological analysis qualitatively showed the enhanced killing of tumor cells adjacent to bone by Ra-223 compared to those treated with IRE alone. CONCLUSION IRE in combination with Ra-223, which enhanced the destruction of cancer cells that are adjacent to bone, resulted in reduction of tumor recurrence through improved clearance of proliferative cells in the tumor region.
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Affiliation(s)
- Raniv D. Rojo
- Department of Interventional Radiology, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, United States of America,College of Medicine, University of the Philippines Manila, Pedro Gil St., Ermita, Manila, National Capital Region 1000, Republic of the Philippines
| | - Joy Vanessa D. Perez
- Department of Interventional Radiology, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, United States of America,College of Medicine, University of the Philippines Manila, Pedro Gil St., Ermita, Manila, National Capital Region 1000, Republic of the Philippines
| | - Jossana A. Damasco
- Department of Interventional Radiology, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, United States of America
| | - Guoyu Yu
- Department of Translational Molecular Pathology, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas, 77030, United States of America
| | - Song-Chang Lin
- Department of Translational Molecular Pathology, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas, 77030, United States of America
| | - Francisco M. Heralde
- College of Medicine, University of the Philippines Manila, Pedro Gil St., Ermita, Manila, National Capital Region 1000, Republic of the Philippines
| | - Nora M. Novone
- Department of Genitourinary Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas, 77030, United States of America
| | - Elmer B. Santos
- Department of Nuclear Medicine, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas, 77030, United States of America
| | - Sue-Hwa Lin
- Department of Translational Molecular Pathology, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas, 77030, United States of America,MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, 6767 Bertner Ave., Houston, Texas, 77030, United States of America
| | - Marites P. Melancon
- Department of Interventional Radiology, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, United States of America,MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, 6767 Bertner Ave., Houston, Texas, 77030, United States of America
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Sano MB, DeWitt MR. Thermochromic Tissue Phantoms for Evaluating Temperature Distribution in Simulated Clinical Applications of Pulsed Electric Field Therapies. Bioelectricity 2020; 2:362-371. [PMID: 34476365 PMCID: PMC8370349 DOI: 10.1089/bioe.2020.0023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: Irreversible electroporation (IRE) induces cell death through nonthermal mechanisms, however, in extreme cases, the treatments can induce deleterious thermal transients. This study utilizes a thermochromic tissue phantom to enable visualization of regions exposed to temperatures above 60°C. Materials and Methods: Poly(vinyl alcohol) hydrogels supplemented with thermochromic ink were characterized and processed to match the electrical properties of liver tissue. Three thousand volt high-frequency IRE protocols were administered with delivery rates of 100 and 200 μs/s. The effect of supplemental internal applicator cooling was then characterized. Results: Baseline treatments resulted thermal areas of 0.73 cm2, which decreased to 0.05 cm2 with electrode cooling. Increased delivery rates (200 μs/s) resulted in thermal areas of 1.5 and 0.6 cm2 without and with cooling, respectively. Conclusions: Thermochromic tissue phantoms enable rapid characterization of thermal effects associated with pulsed electric field treatments. Active cooling of applicators can significantly reduce the quantity of tissue exposed to deleterious temperatures.
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Affiliation(s)
- Michael B. Sano
- UNC/NCSU Joint Department of Biomedical Engineering, Raleigh, North Carolina, USA
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Fesmire CC, Petrella RA, Kaufman JD, Topasna N, Sano MB. Irreversible electroporation is a thermally mediated ablation modality for pulses on the order of one microsecond. Bioelectrochemistry 2020; 135:107544. [DOI: 10.1016/j.bioelechem.2020.107544] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 12/15/2022]
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Sano MB, Petrella RA, Kaufman JD, Fesmire CC, Xing L, Gerber D, Fogle CA. Electro-thermal therapy: Microsecond duration pulsed electric field tissue ablation with dynamic temperature control algorithms. Comput Biol Med 2020; 121:103807. [PMID: 32568680 DOI: 10.1016/j.compbiomed.2020.103807] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 04/27/2020] [Accepted: 05/02/2020] [Indexed: 12/13/2022]
Abstract
Electro-thermal therapy (ETT) is a new cancer treatment modality which combines the use of high voltage pulsed electric fields, dynamic energy delivery rates, and closed loop thermal control algorithms to rapidly and reproducibly create focal ablations. This study examines the ablative potential and profile of pulsed electric field treatments delivered in conjunction with precise temperature control algorithms. An ex vivo perfused liver model was utilized to demonstrate the capability of 5000 V 2 μs duration bipolar electrical pulses and dynamic temperature control algorithms to produce ablations. Using a three applicator array, 4 cm ablation zones were created in under 27 min. In this configuration, the algorithms were able to rapidly achieve and maintain temperatures of 80 °C at the tissue-electrode interface. A simplified single applicator and grounding pad approach was used to correlate the measured ablation zones to electric field isocontours in order to determine lethal electric field thresholds of 708 V/cm and 867 V/cm for 45 °C and 60 °C treatments, respectively. These results establish ETT as a viable method for hepatic tumor treatment with ablation profiles equivalent to other energy based techniques. The single applicator and multi-applicator approaches demonstrated may enable the treatment of complex tumor geometries. The flexibility of ETT temperature control yields a malleable intervention which gives clinicians robust control over the ablation modality, treatment time, and safety profile.
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Affiliation(s)
- Michael B Sano
- UNC/ NCSU Joint Department of Biomedical Engineering, Raleigh, NC, USA.
| | - Ross A Petrella
- UNC/ NCSU Joint Department of Biomedical Engineering, Raleigh, NC, USA
| | - Jacob D Kaufman
- UNC/ NCSU Joint Department of Biomedical Engineering, Raleigh, NC, USA
| | | | - Lei Xing
- Stanford University School of Medicine, Division of Radiation Physics, Stanford, CA, USA
| | - David Gerber
- Division of Abdominal Transplantation, Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Callie A Fogle
- Department of Clinical Sciences and Population Health & Pathobiology, North Carolina State University College of Veterinary Medicine, USA
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