Veterinary Guidelines for Electrochemotherapy of Superficial Tumors

Electrochemotherapy (ECT) consists in the application of electric pulses to increase chemotherapeutic drug intake (bleomycin, cisplatin, or calcium) into the tumor cells. It has become a very valuable treatment option in veterinary oncology. It is an effective and safe treatment modality, which is not only beneficial as a palliative treatment, but also for a curative approach. Performing the treatment adequately will ensure the best results possible, in the minimum number of sessions, and reduce complications. Usually, only one session is enough to achieve excellent results, but the treatment can be repeated. Several sessions can be necessary in the case of incompletely treated or very extended lesions, as well as in the occurrence of new lesions. ECT is effective for superficial or oral tumors of any histology that are accessible to the electrodes. Intravenous bleomycin is the preferred drug and route of administration, leaving other ways of administration and drugs for selected cases. The guidelines presented here are destined to veterinarians who want to develop their understanding of the basis of ECT and wish to perform it adequately and effectively. In this paper, we also discuss common problems and how to solve them, and we include practical tips to improve the treatment results based on common questions and mistakes of beginner users.Fil: Tellado, Matías. No especifíca;Fil: Mir, Lluis M.. No especifíca;Fil: Maglietti, Felipe Horacio. Hospital Italiano; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Electrochemotherapy in treatment of canine oral malignant melanoma and factors influencing treatment outcome

Oral malignant melanoma is the most common, but aggressive oral cancer in dogs with poor prognosis. Electrochemotherapy (ECT) has therapeutic potential in such tumors as effective local treatment. Therefore, the aim of this prospective clinical study was to evaluate treatment effectiveness of ECT in as first line treatment for canine oral malignant melanoma, and search for factors influencing treatment outcome. Sixty-seven canines with primary oral malignant melanoma, non-candidates for first-line therapy, were enrolled. All dogs received ECT and follow-up exams for the span of two years. Based on RECIST criteria, the objective response rate was 100%, 89.5%, 57.7%, and 36.4%, in stage I, II, III and IV, respectively. Only patients in stage I, II and III with partial or complete response improved their quality of life. The median time to progression was 11, 7, 4 and 4 months, and median survival time after the treatment was 16.5, 9.0, 7.5 and 4.5 months, for patients in stage I, II, III and IV, respectively. Significantly better was local response in stage I and II disease (p = 0.0013), without the bone involvement (p = 0.043) Electrochemotherapy is effective local treatment of oral canine malignant melanoma when no alternative treatment is available. Better response is expected in stage I and II patients with tumors without bone involvement.Fil: Tellado, Matías Nicolás. No especifíca;Fil: Maglietti, Felipe Horacio. Hospital Italiano; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Michinski, Sebastián Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Marshall, Guillermo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Signori, Emanuela. Centre National de la Recherche Scientifique; Franci

Canine Oral Eosinophilic Granuloma Treated with Electrochemotherapy

A case of a canine oral eosinophilic granuloma in a 14-year-old female crossbred is described. The dog was presented with a history of ptyalism, halitosis, local pain, decreased appetite, and blood staining noted on food and water bowls. Clinical, hematologic, and biochemical examinations, abdominal ultrasonography, and 3-view chest radiographs were performed, and no metastases were found. Histopathologic examination of two 6 mm punch biopsies from the oral lesion revealed the presence of eosinophilic granulomatous lesions in the submucosa. After treatment with corticosteroids and wide spectrum antibiotics no significant changes in clinical signs and lesion size were observed. Electrochemotherapy (ECT), a novel tumor treatment routinely used for cutaneous and subcutaneous tumors in human patients in the European Union since 2006, was used to treat the eosinophilic granuloma. The procedure was performed under general anesthesia, followed by intravenous administration of bleomycin. Six weeks after treatment a complete response with disappearance of the mass and improvement of clinical signs were observed.Fil: Tellado, Matías Nicolás. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Michinski, Sebastián Diego. Instituto Tecnológico de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Olaiz, Nahuel Manuel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Maglietti, Felipe Horacio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marshall, Guillermo Ricardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Electroporation as the immunotherapy strategy for cancer in veterinary medicine: state of the art in Latin America

Electroporation is a technology that increases cell membrane permeability by the application of electric pulses. Electrochemotherapy (ECT), the best-known application of electroporation, is a very effective local treatment for tumors of any histology in human and veterinary medicine. It induces a local yet robust immune response that is responsible for its high effectiveness. Gene electrotransfer (GET), used in research to produce a systemic immune response against cancer, is another electroporation-based treatment that is very appealing for its effectiveness, low cost, and simplicity. In this review, we present the immune effect of electroporation-based treatments and analyze the results of the vast majority of the published papers related to immune response enhancement by gene electrotransfer in companion animals with spontaneous tumors. In addition, we present a brief history of the initial steps and the state of the art of the electroporation-based treatments in Latin America. They have the potential to become an essential form of immunotherapy in the region. This review gives insight into the subject and helps to choose promising research lines for future work; it also helps to select the adequate treatment parameters for performing a successful application of this technology.Fil: Maglietti, Felipe Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Hospital Italiano; ArgentinaFil: Tellado, Matías. Clínica Vetoncologia; ArgentinaFil: De Robertis, Mariangela. Consiglio Nazionale delle Ricerche; Italia. Università degli Studi di Bari; ItaliaFil: Michinski, Sebastián Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Fernández, Juan. Clínica Vetoncologia; ArgentinaFil: Signori, Emanuela. Consiglio Nazionale Delle Ricerche. Departimento Di Medicina. Instituto Di Farmacología Traslazionale; ItaliaFil: Marshall, Guillermo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; Argentin

Electrochemotherapy immune response enhancement by gene electrotransfer using IL-2 and IL-12 genes in canine patients

Introduction: Electrochemotherapy (ECT) is a treatment strategy which has been gaining territory since the publication of the ESOPE study in 2006. The immune response elicited by ECT is well documented, in fact it is the key to the high response rates obtained by the treatment, but it is ineffective against distant metastasis and also there are some tumors that are non-responding. This could be due to the fact that humoral immune response is elicited instead of cellular response, being the last one much more effective against distant metastasis. We propose the combination of ECT and gene electrotransfer (GET) in order to enhance the immune response and switch it from humoral to cellular type. Patients and methods: Five canine patients with an ECT non-responding tumor were selected regardless of its histology. The patients were treated with ECT, followed by GET using canine IL-2 and IL-12 genes injected in the periphery of the tumor and in the quadriceps muscle. The aim of this strategy is to increase the local immune response through local IL-2 production, and to switch it from humoral to cellular through the IL-12 production at systemic level. After the treatment, the patients were followed for 6 months so far. Results: Side effects were fever, swelling of the transfection sites and lethargy, that resolved with corticosteroid treatment during the first week. In four cases the lesions evaluated stopped growing and remained stable up to now. The fifth case had lung metastasis which reduced their size being undetectable in the control chest radiograph. Conclusion: Our preliminary data show that ECT and GET can be safely and successfully combined. This approach can enhance the immune response in ECT non-responding tumors. Further research is being performed to assess the specific role of GET in combination with ECT treatment.Fil: Maglietti, Felipe Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Michinski, Sebastián Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Emanuela, S.. Laboratory of Molecular Pathology and Experimental Oncology; ItaliaFil: Tellado, Matías Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Marshall, Guillermo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; Argentin

Effects of pulse addition in electropermeabilization: Theoretical insights on the electric conductivity

The electrochemical treatment (ECT) of solid tumors is an electropermeabilization technique firmly established and widely used. In ECT protocols, pulse intensity as well as tissue electric conductivity are of utmost importance for assessing the final electropermeabilized area. Present ECT mathematical modeling based on the solution of the nonlinear Laplace equation for the electric field with a conductivity coefficient depending on the electric field and the temperature have greatly contributed to ECT protocol optimization. However, experimental results from literature report that a succession of pulses may increase tissue electric conductivity and the extent of tissue permeabilization, a phenomenon that present models fail to describe. Here we present new insights of a recently introduced ECT theoretical model that takes into account the effect of pulse addition on tissue electric conductivity. The model describes the electric field with the nonlinear Laplace equation with a conductivity coefficient depending on the electric field, the temperature and the quantity of pulses applied. ECT theoretical predictions show that the rise in the electric current density during the addition of pulses is due solely to an increment in the tissue electric conductivity with no significant changes in the electric field. A potential consequence of these results is that, under certain conditions, it would be possible to obtain larger electropermeabilized areas with the same pulse amplitude simply by increasing the number of pulses. The theoretical implications of this new model lead to a more realistic description of the EP phenomenon, hopefully providing more accurate predictions of ECT treatment outcomes.Fil: Suárez, Cecilia Ana. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Soba, Alejandro. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Maglietti, Felipe Horacio. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Olaiz, Nahuel Manuel. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Marshall, Guillermo Ricardo. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; Argentin

Combined local and systemic bleomycin administration in electrochemotherapy to reduce the number of treatment sessions

Background. Electrochemotherapy (ECT), a medical treatment widely used in human patients for tumor treatment, increases bleomycin toxicity by 1000 fold in the treated area with an objective response rate of around 80%. Despite its high response rate, there are still 20% of cases in which the patients are not responding. This could be ascribed to the fact that bleomycin, when administered systemically, is not reaching the whole tumor mass properly because of the characteristics of tumor vascularization, in which case local administration could cover areas that are unreachable by systemic administration. Patients and methods. We propose combined bleomycin administration, both systemic and local, using companion animals as models. We selected 22 canine patients which failed to achieve a complete response after an ECT treatment session. Eleven underwent another standard ECT session (control group), while 11 received a combined local and systemic administration of bleomycin in the second treatment session. Results. According to the WHO criteria, the response rates in the combined administration group were: complete response (CR) 54% (6), partial response (PR) 36% (4), stable disease (SD) 10% (1). In the control group, these were: CR 0% (0), PR 19% (2), SD 63% (7), progressive disease (PD) 18% (2). In the combined group 91% objective responses (CR+PR) were obtained. In the control group 19% objective responses were obtained. The difference in the response rate between the treatment groups was significant (p < 0.01). Conclusions. Combined local and systemic bleomycin administration was effective in previously to ECT non responding canine patients. The results indicate that this approach could be useful and effective in specific population of patients and reduce the number of treatment sessions needed to obtain an objective response.Fil: Maglietti, Felipe Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Tellado, Matías Nicolás. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Area de Vet. en Salud Publica; ArgentinaFil: Olaiz, Nahuel Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Michinski, Sebastián Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Marshall, Guillermo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; Argentin

Electrochemotherapy in treatment of canine oral malignant melanoma and factors influencing treatment outcome

Oral malignant melanoma is the most common, but aggressive oral cancer in dogs with poor prognosis. Electrochemotherapy (ECT) has therapeutic potential in such tumors as effective local treatment. Therefore, the aim of this prospective clinical study was to evaluate treatment effectiveness of ECT in as first line treatment for canine oral malignant melanoma, and search for factors influencing treatment outcome

Electrochemotherapy in non-satisfactory responding tumors in vet patients: Combined administration of bleomycin, systemic and local

Electrochemotherapy (ECT), a medical treatment widely used in human tumor treatment, consists in the administration of bleomycin either systemically or locally followed by the application of an electric field. This procedure increases the toxicity of the bleomycin by 1000 fold in the treated area with an objective response rate of around 80%. Despite its success related to efficiency, low cost and minimum side effects, there is still a 20% of cases in which the ECT treatment is not responding. This could be ascribed to the fact that bleomycin, administered in the preferred way, that is, systemically for large tumors, is not properly reaching the whole tumor mass. The main cause is poor tumor vascularization, in which case local administration could cover areas unreachable with systemic administration. To address this problem here we propose the combined administration of bleomycin, systemic and locally, using companion animals as models for ECT tumor treating. Accordingly, we selected 7 canine and 2 feline patients with a single tumor with poor or no response to ECT, and then we repeat the treatment with ECT but now with a combined administration of bleomycin, systemic and local. The results show, according to an evaluation using the WHO criteria of tumor response, that from the 9 cases, 5 achieved a Complete Response, 3 a Partial Response, and 1 a Stable Disease after 30 days from the combined treatment date. In conclusion, the combined administration of bleomycin, systemic and local, in ECT could provide a good response in tumors that previously showed an unsatisfactory response. It is expected that these results could hopefully increase ECT efficiency.Fil: Maglietti, Felipe Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Tellado, Matías Nicolás. Universidad de Buenos Aires; ArgentinaFil: Olaiz, Nahuel Manuel. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Michinski, Sebastián Diego. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Marshall, Guillermo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentin

Pulsed electric fields using a multiple needle chamber to improve bioactive compounds extraction from unprocessed Opuntia ficus-indica fruits

Prickly pear fruit is rich in natural pigments and bioactive compounds that contribute to its antioxidant capacity and health-promoting properties. These compounds can be extracted using pulsed electric fields (PEF), a non-thermal technology that is energy efficient and is being increasingly used for food processing. For that end, a novel electroporation chamber was designed and optimum pulse parameters were selected maximizing juice yield and bioactive compounds extraction. The chamber consists of 5 rows of 10 parallel needles, and the optimum pulse parameters were: Sixty 100 μs long pulses of 1200 V/cm at a frequency of 10 Hz. The average energy input was 11.44 kJ/kg (temperature rise below 10 °C). When comparing PEF-treated samples with untreated ones, juice yield increased 3.3 times, and betalain extraction 1.48 times. Also, the juice extracted had a significantly higher total polyphenol content (1.4 times), and antioxidant capacity (1.4–1.5 times increase, measured by three techniques). This chamber and procedure could be scaled for industrial applications since large samples can be treated without the need of adding conductive medium or peeling the fruits, simplifying the procedure and reducing costs. PEF treatment of prickly pear fruits can effectively provide juice rich in natural colorants and with higher nutritional properties.Fil: Surano, Bárbara Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Leiva, Graciela Edith. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; ArgentinaFil: Marshall, Guillermo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Maglietti, Felipe Horacio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; ArgentinaFil: Schebor, Carolina Claudia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; Argentin