1
|
Spiliotis AE, Holländer S, Wagenpfeil G, Eisele R, Nika S, Mallis Kyriakides O, Laschke MW, Menger MD, Glanemann M, Gäbelein G. Electrochemotherapy with intravenous, intratumoral, or combined administration of bleomycin in the treatment of colorectal hepatic metastases in a rat model. Sci Rep 2024; 14:17361. [PMID: 39075095 PMCID: PMC11286835 DOI: 10.1038/s41598-024-67878-x] [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: 05/20/2024] [Accepted: 07/17/2024] [Indexed: 07/31/2024] Open
Abstract
Electrochemotherapy (ECT) combines the reversible electroporation (rEP) with intravenous (i.v.) or intratumoral (i.t.) administration of chemotherapeutic drugs. We conducted this study to compare the efficacy of i.v., i.t., and i.v. + i.t. injection of bleomycin (BLM) in ECT treatment of colorectal hepatic metastases in a rat model. WAG/Rij rats were randomized into three groups and underwent ECT with i.v., i.t., or i.v. + i.t. injection of BLM. Tumor volumes and oxygenation were measured by means of ultrasound and photoacoustic imaging. Moreover, liver and tumor tissue were analyzed by histology and immunohistochemistry. The i.v. and i.v. + i.t. groups exhibited a 44.0% and 46.6% reduction in oxygen saturation of the tumor tissue when compared to pretreatment values, whereas the i.t. group only showed a reduction of 35.2%. The extent of tumor tissue necrosis did not statistically differ between the groups. However, the i.t. group showed a tendency towards a lower necrosis rate. Cell proliferation, apoptotic cell death, vascularization, and immune cell infiltration were comparable in the treated tumors of the three groups. ECT with i.v. administration of BLM should be preferred in clinical practice, as the combined i.v. + i.t. therapy did not show superior oncological outcomes in the present study.
Collapse
Affiliation(s)
- Antonios E Spiliotis
- Institute for Clinical and Experimental Surgery, Saarland University, 66421, Homburg, Germany.
- Department of Surgery, Charité Universitätsmedizin Berlin, Campus Charité Mitte, Campus Virchow Klinikum, 13353, Berlin, Germany.
| | - Sebastian Holländer
- Department of General Surgery, Vascular-, Visceral- and Pediatric Surgery, Saarland University Medical Center, 66421, Homburg, Germany
| | - Gudrun Wagenpfeil
- Saarland University Medical Center, Institute for Medical Biometry, Epidemiology and Medical Informatics, 66421, Homburg, Germany
| | - Robert Eisele
- Department of General Surgery, Vascular-, Visceral- and Pediatric Surgery, Saarland University Medical Center, 66421, Homburg, Germany
| | - Spyridon Nika
- Department of Urology and Pediatric Urology, Saarland University Medical Center, 66421, Homburg, Germany
| | - Orestis Mallis Kyriakides
- Department of General Surgery, Vascular-, Visceral- and Pediatric Surgery, Saarland University Medical Center, 66421, Homburg, Germany
| | - Matthias W Laschke
- Institute for Clinical and Experimental Surgery, Saarland University, 66421, Homburg, Germany
| | - Michael D Menger
- Institute for Clinical and Experimental Surgery, Saarland University, 66421, Homburg, Germany
| | - Matthias Glanemann
- Department of General Surgery, Vascular-, Visceral- and Pediatric Surgery, Saarland University Medical Center, 66421, Homburg, Germany
| | - Gereon Gäbelein
- Department of General Surgery, Vascular-, Visceral- and Pediatric Surgery, Saarland University Medical Center, 66421, Homburg, Germany
| |
Collapse
|
2
|
Coskun A, Kayhan H, Senturk F, Esmekaya MA, Canseven AG. The Efficacy of Electrochemotherapy with Dacarbazine on Melanoma Cells. Bioelectricity 2024; 6:118-125. [PMID: 39119570 PMCID: PMC11305008 DOI: 10.1089/bioe.2023.0041] [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: 08/10/2024] Open
Abstract
Electrochemotherapy (ECT) involves locally applying electrical pulses to permeabilize cell membranes, using electroporation (EP). This process enhances the uptake of low-permeant chemotherapeutic agents, consequently amplifying their cytotoxic effects. In melanoma treatment, dacarbazine (DTIC) is a cornerstone, but it faces limitations because of poor cell membrane penetration, necessitating the use of high doses, which, in turn, leads to increased side effects. In our study, we investigated the effects of DTIC and EP, both individually and in combination, on the melanoma cell line (SK-MEL-30) as well as human dermal fibroblasts (HDF) using in vitro assays. First, the effects of different DTIC concentrations on the viability of SK-MEL-30 and HDF cells were determined, revealing that DTIC was more effective against melanoma cells at lower concentrations, whereas its cytotoxicity at 1000 μM was similar in both cell types. Next, an ideal electric field strength of 1500 V/cm achieved a balance between permeability (84%) and melanoma cell viability (79%), paving the way for effective ECT. The combined DTIC-EP (ECT) application reduced IC50 values by 2.2-fold in SK-MEL-30 cells and 2.7-fold in HDF cells compared with DTIC alone. In conclusion, ECT not only increased DTIC's cytotoxicity against melanoma cells but also affected healthy fibroblasts. These findings emphasize the need for cautious, targeted ECT management in melanoma therapy.
Collapse
Affiliation(s)
- Alaaddin Coskun
- Department of Biophysics, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Handan Kayhan
- Department of Adult Hematology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Fatih Senturk
- Department of Biophysics, Faculty of Medicine, Duzce University, Duzce, Turkey
| | - Meric Arda Esmekaya
- Department of Biophysics, Faculty of Medicine, Gazi University, Ankara, Turkey
| | | |
Collapse
|
3
|
Scuderi M, Dermol-Cerne J, Scancar J, Markovic S, Rems L, Miklavcic D. The equivalence of different types of electric pulses for electrochemotherapy with cisplatin - an in vitro study. Radiol Oncol 2024; 58:51-66. [PMID: 38378034 PMCID: PMC10878774 DOI: 10.2478/raon-2024-0005] [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: 11/20/2023] [Accepted: 12/05/2023] [Indexed: 02/22/2024] Open
Abstract
BACKGROUND Electrochemotherapy (ECT) is a treatment involving the administration of chemotherapeutics drugs followed by the application of 8 square monopolar pulses of 100 μs duration at a repetition frequency of 1 Hz or 5000 Hz. However, there is increasing interest in using alternative types of pulses for ECT. The use of high-frequency short bipolar pulses has been shown to mitigate pain and muscle contractions. Conversely, the use of millisecond pulses is interesting when combining ECT with gene electrotransfer for the uptake of DNA-encoding proteins that stimulate the immune response with the aim of converting ECT from a local to systemic treatment. Therefore, the aim of this study was to investigate how alternative types of pulses affect the efficiency of the ECT. MATERIALS AND METHODS We performed in vitro experiments, exposing Chinese hamster ovary (CHO) cells to conventional ECT pulses, high-frequency bipolar pulses, and millisecond pulses in the presence of different concentrations of cisplatin. We determined cisplatin uptake by inductively coupled plasma mass spectrometry and cisplatin cytotoxicity by the clonogenic assay. RESULTS We observed that the three tested types of pulses potentiate the uptake and cytotoxicity of cisplatin in an equivalent manner, provided that the electric field is properly adjusted for each pulse type. Furthermore, we quantified that the number of cisplatin molecules, resulting in the eradication of most cells, was 2-7 × 107 per cell. CONCLUSIONS High-frequency bipolar pulses and millisecond pulses can potentially be used in ECT to reduce pain and muscle contraction and increase the effect of the immune response in combination with gene electrotransfer, respectively.
Collapse
Affiliation(s)
- Maria Scuderi
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Janja Dermol-Cerne
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Janez Scancar
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Stefan Markovic
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Lea Rems
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Damijan Miklavcic
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Tsimpaki T, Anastasova R, Liu H, Seitz B, Bechrakis NE, Berchner-Pfannschmidt U, Kraemer MM, Fiorentzis M. Calcium Electroporation versus Electrochemotherapy with Bleomycin in an In Vivo CAM-Based Uveal Melanoma Xenograft Model. Int J Mol Sci 2024; 25:938. [PMID: 38256012 PMCID: PMC10815639 DOI: 10.3390/ijms25020938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/05/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
Despite recent advancements in the diagnosis and treatment of uveal melanoma (UM), its metastatic rate remains high and is accompanied by a highly dismal prognosis, constituting an unmet need for the development of novel adjuvant therapeutic strategies. We established an in vivo chick chorioallantoic membrane (CAM)-based UM xenograft model from UPMD2 and UPMM3 cell lines to examine its feasibility for the improvement of selection of drug candidates. The efficacy of calcium electroporation (CaEP) with 5 or 10 mM calcium chloride (Ca) and electrochemotherapy (ECT) with 1 or 2.5 µg/mL bleomycin in comparison to monotherapy with the tested drug or electroporation (EP) alone was investigated on the generated UM tumors. CaEP and ECT showed a similar reduction of proliferation and melanocytic expansion with a dose-dependent effect for bleomycin, whereas CaEP induced a significant increase of the apoptosis and a reduction of vascularization with varying sensitivity for the two xenograft types. Our in vivo results suggest that CaEP and ECT may facilitate the adequate local tumor control and contribute to the preservation of the bulbus, potentially opening new horizons in the adjuvant treatment of advanced UM.
Collapse
Affiliation(s)
- Theodora Tsimpaki
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| | - Ralitsa Anastasova
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| | - Hongtao Liu
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| | - Berthold Seitz
- Department of Ophthalmology, Saarland University Medical Center, Kirrberger Str. 100, 66421 Homburg, Germany;
| | - Nikolaos E. Bechrakis
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| | - Utta Berchner-Pfannschmidt
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| | - Miriam M. Kraemer
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| | - Miltiadis Fiorentzis
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Hufeland Str. 55, 45147 Essen, Germany; (T.T.); (R.A.); (H.L.); (N.E.B.); (U.B.-P.); (M.M.K.)
| |
Collapse
|
6
|
Bieżuńska-Kusiak K, Kulbacka J, Choromańska A, Rembiałkowska N, Michel O, Saczko J. Evaluation of the Anticancer Activity of Calcium Ions Introduced into Human Breast Adenocarcinoma Cells MCF-7/WT and MCF-7/DOX by Electroporation. Pharmaceuticals (Basel) 2023; 16:809. [PMID: 37375757 DOI: 10.3390/ph16060809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/18/2023] [Accepted: 05/22/2023] [Indexed: 06/29/2023] Open
Abstract
Breast cancer ranks among the top three most common malignant neoplasms in Poland. The use of calcium ion-assisted electroporation is an alternative approach to the classic treatment of this disease. The studies conducted in recent years confirm the effectiveness of electroporation with calcium ions. Electroporation is a method that uses short electrical pulses to create transitional pores in the cell membrane to allow the penetration of certain drugs. The aim of this study was to investigate the antitumor effects of electroporation alone and calcium ion-assisted electroporation on human mammary adenocarcinoma cells that are sensitive (MCF-7/WT) and resistant to doxorubicin (MCF-7/DOX). The cell viability was assessed using independent tests: MTT and SRB. The type of cell death after the applied therapy was determined by TUNEL and flow cytometry (FACS) methods. The expression of Cav3.1 and Cav3.2 proteins of T-type voltage-gated calcium channels was assessed by immunocytochemistry, and changes in the morphology of CaEP-treated cells were visualized using a holotomographic microscope. The obtained results confirmed the effectiveness of the investigated therapeutic method. The results of the work constitute a good basis for planning research at the in vivo level and in the future to develop a more effective and safer method of breast cancer treatment for patients.
Collapse
Affiliation(s)
- Katarzyna Bieżuńska-Kusiak
- Department of Molecular and Cellular Biology, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland
| | - Julita Kulbacka
- Department of Molecular and Cellular Biology, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland
- Department of Immunology, State Research Institute Centre for Innovative Medicine, Santariškių 5, 08410 Vilnius, Lithuania
| | - Anna Choromańska
- Department of Molecular and Cellular Biology, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland
| | - Nina Rembiałkowska
- Department of Molecular and Cellular Biology, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland
| | - Olga Michel
- Department of Cytobiochemistry, University of Wroclaw, F. Joliot-Curie 14a, 50-383 Wroclaw, Poland
| | - Jolanta Saczko
- Department of Molecular and Cellular Biology, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland
| |
Collapse
|
7
|
Kesar U, Markelc B, Jesenko T, Ursic Valentinuzzi K, Cemazar M, Strojan P, Sersa G. Effects of Electrochemotherapy on Immunologically Important Modifications in Tumor Cells. Vaccines (Basel) 2023; 11:vaccines11050925. [PMID: 37243029 DOI: 10.3390/vaccines11050925] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/25/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Electrochemotherapy (ECT) is a clinically acknowledged method that combines the use of anticancer drugs and electrical pulses. Electrochemotherapy with bleomycin (BLM) can induce immunogenic cell death (ICD) in certain settings. However, whether this is ubiquitous over different cancer types and for other clinically relevant chemotherapeutics used with electrochemotherapy is unknown. Here, we evaluated in vitro in the B16-F10, 4T1 and CT26 murine tumor cell lines, the electrochemotherapy triggered changes in the ICD-associated damage-associated molecular patterns (DAMPs): Calreticulin (CRT), ATP, High Mobility Group Box 1 (HMGB1), and four immunologically important cellular markers: MHCI, MHC II, PD-L1 and CD40. The changes in these markers were investigated in time up to 48 h after ECT. We showed that electrochemotherapy with all three tested chemotherapeutics induced ICD-associated DAMPs, but the induced DAMP signature was cell line and chemotherapeutic concentration specific. Similarly, electrochemotherapy with CDDP, OXA or BLM modified the expression of MHC I, MHC II, PD-L1 and CD40. The potential of electrochemotherapy to change their expression was also cell line and chemotherapeutic concentration specific. Our results thus put the electrochemotherapy with clinically relevant chemotherapeutics CDDP, OXA and BLM on the map of ICD inducing therapies.
Collapse
Affiliation(s)
- Ursa Kesar
- Department of Experimental Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Bostjan Markelc
- Department of Experimental Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
| | - Tanja Jesenko
- Department of Experimental Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Katja Ursic Valentinuzzi
- Department of Experimental Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Maja Cemazar
- Department of Experimental Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Faculty of Health Sciences, University of Primorska, 6310 Izola, Slovenia
| | - Primoz Strojan
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
- Department of Radiation Oncology, Institute of Oncology, 1000 Ljubljana, Slovenia
| | - Gregor Sersa
- Department of Experimental Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Faculty of Health Sciences, University of Ljubljana, 1000 Ljubljana, Slovenia
| |
Collapse
|
8
|
Induction of Bystander and Abscopal Effects after Electroporation-Based Treatments. Cancers (Basel) 2022; 14:cancers14153770. [PMID: 35954434 PMCID: PMC9367330 DOI: 10.3390/cancers14153770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/21/2022] [Accepted: 07/30/2022] [Indexed: 02/01/2023] Open
Abstract
Simple Summary The delivery of electric field to tumor cells or nodules induces cell electroporation that allows intracellular delivery of cytotoxic agents and eventually inhibits tumor growth. In this study, we showed that intracellular delivery of calcium ions and anticancer drug bleomycin not only kills the cells but also has a negative bystander effect on indirectly treated cells. We also showed that, when directly applied to one tumor, these treatments can inhibit the growth of a second, non-electroporated tumor. Abstract Electroporation-based antitumor therapies, including bleomycin electrotransfer, calcium electroporation, and irreversible electroporation, are very effective on directly treated tumors, but have no or low effect on distal nodules. In this study, we aimed to investigate the abscopal effect following calcium electroporation and bleomycin electrotransfer and to find out the effect of the increase of IL-2 serum concentration by muscle transfection. The bystander effect was analyzed in in vitro studies on 4T1tumor cells, while abscopal effect was investigated in an in vivo setting using Balb/c mice bearing 4T1 tumors. ELISA was used to monitor IL-2 serum concentration. We showed that, similarly to cell treatment with bleomycin electrotransfer, the bystander effect occurs also following calcium electroporation and that these effects can be combined. Combination of these treatments also resulted in the enhancement of the abscopal effect in vivo. Since these treatments resulted in an increase of IL-2 serum concentration only in mice bearing one but not two tumors, we increased IL-2 serum concentration by muscle transfection. Although this did not enhance the abscopal effect of combined tumor treatment using calcium electroporation and bleomycin electrotransfer, boosting of IL-2 serum concentration had a significant inhibitory effect on directly treated tumors.
Collapse
|