mEHT Treatment Research Articles

Immune Marker and C-Reactive Protein Dynamics and Their Prognostic Implications in Modulated Electro-Hyperthermia Treatment in Advanced Pancreatic Cancer: A Retrospective Analysis

Background: Previous research has suggested that modulated electro-hyperthermia (mEHT) can be used to induce anti-tumor immune effects and to extend patient survival. The use of mEHT in advanced pancreatic cancer is beneficial; however, its immune-mediating effects were never investigated. Methods: A retrospective observational study was conducted. Leukocyte counts, C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), and granulocyte-to-lymphocyte ratio (GLR) were measured at baseline, midpoint, and after mEHT treatment. Results: A total of 73 mEHT treated pancreatic cancer patients were included. The time elapsed between tumor diagnosis and the first mEHT treatment was 4.40 ± 5.70 months. While no change could be observed between the baseline and the first follow-up visits, the total white blood cell (WBC), neutrophil, and granulocyte count, CRP, NLR, and GLR were significantly higher at the second follow-up compared to both previous visits. Higher levels of the latter parameters following the last mEHT treatment were signaling significantly poor prognostic signs, and so were their longitudinal changes. Conclusions: After the initiation of mEHT, immune markers stabilize with the treatment, but this positive effect is eroded over time by progressive disease. Monitoring the changes in these markers and the occurrence of their increase is a prognostic marker of shorter survival.

Modulated Electro-Hyperthermia Supports the Effect of Gemcitabine Both in Sensitive and Resistant Pancreas Adenocarcinoma Cell Lines.

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is frequently associated to high treatment resistance. Gemcitabine (GEM) alone or in combination is the most used chemotherapy for unresecable PDACs. Here we studied whether modulated electro-hyperthermia (mEHT), a non-invasive complementary treatment, can support the effect of GEM on PDAC cells in vitro. The LD20 for the GEM-resistant Panc1 cells proved to be 200× higher than for the drug-sensitive Capan1. The mEHT alone caused significant apoptosis in Capan1 cultures as confirmed by the elevated SubG1 phase cell fraction and increased number of cleaved Caspase-3 positive cells 48 h after treatment, with an additive effect when GEM was used after hyperthermia. These were accompanied by reduced number of G1, S, and G2/M phase cells and elevated expression of the cyclin-dependent kinase inhibitor p21waf1 protein. In GEM-resistant Panc1 cells, an initial apoptosis was detected by flow cytometry 24 h after mEHT ± GEM treatment, which however diminished by 48 h at persistent number of cleaved Caspase-3 positive tumor cells. Though GEM monotherapy reduced the number of tumor progenitor colonies in Capan1 cell line, an additive colony inhibitory effect of mEHT was observed after mEHT + GEM treatment. The heat shock induced Hsp27 and Hsp70 proteins, which are known to sensitize PDAC cells to GEM were upregulated in both Capan1 and Panc1 cells 24 h after mEHT treatment. The level of E-Cadherin, a cell adhesion molecule, increased in Capan1 cells after mEHT + GEM treatment. In conclusion, in GEM-sensitive PDAC cells mEHT treatment alone induced cell death and cell cycle inhibition and improved GEM efficiency in combination, which effects were milder and short-term up to 24 h in the GEM-resistant Panc1 cells. Our data further support the inclusion of hyperthermia, in particular of mEHT, into the traditional oncotherapy regimens of PDAC.

Modulated Electro-Hyperthermic (mEHT) Treatment in the Therapy of Inoperable Pancreatic Cancer Patients-A Single-Center Case-Control Study.

Our present oncological treatment arsenal has limited treatment options for pancreatic ductal adenocarcinoma (PDAC). Extended reviews have shown the benefits of hyperthermia for PDAC, supporting the perspectives with the improvements of the treatment possibilities. METHODS: A retrospective single-center case-control study was conducted with the inclusion of 78 inoperable PDAC patients. Age-, sex-, chemotherapy-, stage-, and ascites formation-matched patients were assigned to two equal groups based on the application of modulated electro-hyperthermia (mEHT). The EHY2030 mEHT device was used. RESULTS: A trend in favor of mEHT was found in overall survival (p = 0.1420). To further evaluate the potential beneficial effects of mEHT, the presence of distant metastasis or ascites in the patients’ oncological history was investigated. Of note, mEHT treatment had a favorable effect on patients’ overall survival in metastatic disease (p = 0.0154), while less abdominal fluid responded to the mEHT treatment in a more efficient way (p ≤ 0.0138). CONCLUSION: mEHT treatment was associated with improved overall survival in PDAC in our single-center retrospective case-control study. The outcome measures encourage us to design a randomized prospective clinical study to further confirm the efficiency of mEHT in this patient cohort.

Suppression of Metastatic Melanoma Growth in Lung by Modulated Electro-Hyperthermia Monitored by a Minimally Invasive Heat Stress Testing Approach in Mice.

Simple SummaryThe lung is the most frequent site of distant melanoma metastases. Metastases of melanoma in the lungs offer a very poor prognosis, with a 5-year survival rate of below 10%. Hyperthermic therapies including modulated electro-hyperthermia (mEHT) in clinical settings have been used to improve the efficacy of radiotherapy, chemotherapy, and immunotherapy of tumors. In this study, we focused primarily on the optimization of mEHT for targeted lung treatment of mice lungs burdened with B16F10 melanoma pulmonary metastases, with a particular focus on elucidating the mechanism of action of mEHT on treated melanoma cells while investigating any potential treatment-related side effects on normal lung tissue. mEHT showed evidence of significant anti-tumor effects as demonstrated by the reduced number of pulmonary metastatic nodules, DNA damage response, downregulation of Ki67 expression, higher immune cell infiltration, and upregulation of p21waf1 expression in mEHT-treated tumors.Modulated electro-hyperthermia (mEHT) is a novel complementary therapy in oncology which is based on the higher conductivity and permittivity of cancerous tissues due to their enhanced glycolytic activity and ionic content compared to healthy normal tissues. We aimed to evaluate the potential of mEHT, inducing local hyperthermia, in the treatment of pulmonary metastatic melanoma. Our primary objective was the optimization of mEHT for targeted lung treatment as well as to identify the mechanism of its potential anti-tumor effect in the B16F10 mouse melanoma pulmonary metastases model while investigating the potential treatment-related side effects of mEHT on normal lung tissue. Repeated treatment of tumor-bearing lungs with mEHT induced significant anti-tumor effects as demonstrated by the lower number of tumor nodules and the downregulation of Ki67 expression in treated tumor cells. mEHT treatment provoked significant DNA double-strand breaks indicated by the increased expression of phosphorylated H2AX protein in treated tumors, although treatment-induced elevation of cleaved/activated caspase-3 expression was insignificant, suggesting the minimal role of apoptosis in this process. The mEHT-related significant increase in p21waf1 positive tumor cells suggested that p21waf1-mediated cell cycle arrest plays an important role in the anti-tumor effect of mEHT on melanoma metastases. Significantly increased CD3+, CD8+ T-lymphocytes, and F4/80+CD11b+ macrophage density in the whole lung and tumor of treated animals emphasizes the mobilizing capability of mEHT on immune cells. In conclusion, mEHT can reduce the growth potential of melanoma, thus offering itself as a complementary therapeutic option to chemo- and/or radiotherapy.

Exhaustion of Protective Heat Shock Response Induces Significant Tumor Damage by Apoptosis after Modulated Electro-Hyperthermia Treatment of Triple Negative Breast Cancer Isografts in Mice.

Simple SummaryBreast cancer is one of the most frequent cancer types among women worldwide. Triple-negative breast cancer is a highly aggressive breast cancer type with very poor survival due to the lack of targeted therapy. Modulated electro-hyperthermia (mEHT) is a newly emerging form of adjuvant, electromagnetic cancer-treatment. Capacitive energy delivery and frequency modulation enable the application of non-thermal effects. Furthermore, selective energy absorption by the tumor (as demonstrated in our present paper) enables 2.5 °C selective heating of the tumor. In the present study, we demonstrate in an in vivo syngeneic Balb/c TNBC mouse model that mEHT caused a remarkable reduction in the number of viable tumor cells accompanied by significant cleaved caspase-3-related apoptotic tumor tissue destruction and a transitional heat shock response. Furthermore, we demonstrated in vitro that the tumor cell killing effect of mEHT was amplified by inhibitors of the protective heat shock response such as Quercetin and KRIBB11.Modulated electro-hyperthermia (mEHT) is a complementary antitumor therapy applying capacitive radiofrequency at 13.56 MHz. Here we tested the efficiency of mEHT treatment in a BALB/c mouse isograft model using the firefly luciferase-transfected triple-negative breast cancer cell line, 4T1. Tumors inoculated orthotopically were treated twice using a novel ergonomic pole electrode and an improved mEHT device (LabEHY 200) at 0.7 ± 0.3 W for 30 min. Tumors were treated one, two, or three times every 48 h. Tumor growth was followed by IVIS, caliper, and ultrasound. Tumor destruction histology and molecular changes using immunohistochemistry and RT-qPCR were also revealed. In vivo, mEHT treatment transitionally elevated Hsp70 expression in surviving cells indicating heat shock-related cell stress, while IVIS fluorescence showed a significant reduction of viable tumor cell numbers. Treated tumor centers displayed significant microscopic tumor damage with prominent signs of apoptosis, and major upregulation of cleaved/activated caspase-3-positive tumor cells. Serial sampling demonstrated substantial elevation of heat shock (Hsp70) response twelve hours after the treatment which was exhausted by twenty-four hours after treatment. Heat shock inhibitors Quercetin or KRIBB11 could synergistically amplify mEHT-induced tumor apoptosis in vitro. In conclusion, modulated electro-hyperthermia exerted a protective heat shock response as a clear sign of tumor cell stress. Exhaustion of the HSR manifested in caspase-dependent apoptotic tumor cell death and tissue damage of triple-negative breast cancer after mEHT monotherapy. Inhibiting the HSR synergistically increased the effect of mEHT. This finding has great translational potential.

Modulated Electro-Hyperthermia Resolves Radioresistance of Panc1 Pancreas Adenocarcinoma and Promotes DNA Damage and Apoptosis In Vitro.

The poor outcome of pancreas ductal adenocarcinomas (PDAC) is frequently linked to therapy resistance. Modulated electro-hyperthermia (mEHT) generated by 13.56 MHz capacitive radiofrequency can induce direct tumor damage and promote chemo- and radiotherapy. Here, we tested the effect of mEHT either alone or in combination with radiotherapy using an in vivo model of Panc1, a KRAS and TP53 mutant, radioresistant PDAC cell line. A single mEHT shot of 60 min induced ~50% loss of viable cells and morphological signs of apoptosis including chromatin condensation, nuclear shrinkage and apoptotic bodies. Most mEHT treatment related effects exceeded those of radiotherapy, and these were further amplified after combining the two modalities. Treatment related apoptosis was confirmed by a significantly elevated number of annexin V single-positive and cleaved/activated caspase-3 positive tumor cells, as well as sub-G1-phase tumor cell fractions. mEHT and mEHT+radioterapy caused the moderate accumulation of γH2AX positive nuclear foci, indicating DNA double-strand breaks and upregulation of the cyclin dependent kinase inhibitor p21waf1 besides the downregulation of Akt signaling. A clonogenic assay revealed that both mono- and combined treatments affected the tumor progenitor/stem cell populations too. In conclusion, mEHT treatment can contribute to tumor growth inhibition and apoptosis induction and resolve radioresistance of Panc1 PDAC cells.

Relationship between Energy Dosage and Apoptotic Cell Death by Modulated Electro-Hyperthermia

Modulated electro-hyperthermia (mEHT) is a form of mild hyperthermia (HT) used for cancer treatment. The principle utility of HT is the ability not only to increase cell temperature, but also to increase blood flow and associated pO2 to the microenvironment. While investigational evidence has shown the unique ability of mEHT to elicit apoptosis in cancer cells, in vivo and in vitro, the same trait has not been observed with conventional HT. There is dissension as to what allows mEHT to elicit apoptosis despite heating to only mild temperatures, with the predominant opinion in favor of increased temperature at a cellular level as the driving force. For this study, we hypothesized that in addition to temperature, the amount of electrical energy delivered is a major factor in induction of apoptosis by mEHT. To evaluate the impact of electrical energy on apoptosis, we divided generally practiced mEHT treatment into 3 phases: Phase I (treatment start to 10 min. mark): escalation from 25 °C to 37 °C Phase II (10 min. mark to 15 min. mark): escalation from 37 °C to 42 °C Phase III (15 min. mark to 45 min. mark): maintenance at 42 °C Combinations of mEHT at 18 W power, mEHT at 7.5 W power, water bath, and incubator were applied to each of the three phases. Power output was recorded per second and calculated as average power per second. Total number of corresponding Joules emitted per each experiment was also recorded. The biological effect of apoptotic cell death was assayed by annexin-V assay. In group where mEHT was applied for all three phases, apoptosis rate was measured at 31.18 ± 1.47%. In group where mEHT was only applied in Phases II and III, apoptosis rate dropped to 20.2 ± 2.1%. Where mEHT was only applied in Phase III, apoptosis was 6.4 ± 1.7%. Interestingly, when mEHT was applied in Phases I and II, whether Phase III was conducted in either water bath at 42 °C or incubator at 37 °C, resulted in nearly identical apoptosis rates, 26 ± 4.4% and 25.9 ± 3.1%, respectively. These results showed that accumulation of mEHT at high-powered setting (18 W/sec) during temperature escalation (Phase I and Phase II), significantly increased apoptosis of tested cancer cells. The data also showed that whereas apoptosis rate was significantly increased during temperature escalation by higher power (18 W/sec), apoptosis was limited during temperature maintenance with lower power (7.5 W/sec). This presents that neither maintenance of 42 °C nor accumulation of Joules by mEHT has immediate correlating effect on apoptosis rate. These findings may offer a basis for direction of clinical application of mEHT treatment.

Modulated electro‐hyperthermia suppresses H19, a tumor promoting long non coding RNA, in a triple‐negative breast cancer model

IntroductionModulated electro‐hyperthermia (mEHT) is a complementary antitumor therapy, based on selective tumor cell killing by a 13.56 MHz radiofrequency induced electric field. The H19 long non coding RNA (lncRNA) is involved in tumor progression and metastasis. It’s overexpression is associated with poor prognosis and therapy resistance in breast cancer. We observed previously significant tumor inhibitory effects of mEHT.AimsOur aim was to investigate the hypothesis, that mEHT effects are related to H19 lncRNA inhibition in triple negative breast cancer (TNBC) spheroids and in a TNBC bearing mouse model.Methods4T1 spheroids were embedded in Matrigel® and treated with a single mEHT, conventional hyperthermia (cHT) or normothermia (Ctr) for 30 minutes. Spheroids were collected 24 hours after treatment, RNA was isolated and processed for Real‐Time PCR (RT‐PCR). TNBC cells (highly aggressive 4T1 or less aggressive 4T07) were inoculated orthotopically in female BALB/c mice. Tumor growth was monitored in vivo by digital caliper and ultrasound (Phillips Sonos 5500), mice were randomized into two groups based on tumor size. Mice were treated with mEHT in monotherapy or in combination with methotrexate (MTX) 2 or 3 times for 30 minutes with 0.7±0.3W power to achieve 40°C skin temperature above the tumor. At the end of the experiments mice were euthanized, the tumors were dissected and processed for molecular biologic techniques. H19 expression was measured with RT‐PCR, results were normalized to GAPDH.ResultsSingle mEHT or cHT treatment of 4T1 spheroids reduced significantly H19 expression compared to a normothermic control (Ctr:0.004±0.0004, cHT:0.001±0.0001 mEHT:0.0006±0.0002, p<0.0001). mEHT decreased H19 expression more effectively, than conventional HT (cHT:0.001±0.0001 mEHT:0.0006±0.0002, p<0.01). There was a significant decrease in H19 expression of 4T1 tumors in vivo after two (sham:0.068±0.044, mEHT:0.033±0.024, p<0.05) and three mEHT treatments (sham:0.097±0.059 vs mEHT:0.050±0.030, p<0.05) compared to the sham group. In case of combination treatments H19 expression was significantly lower in the mEHT+MTX group compared to MTX only (MTX:0.104±0,038 vs mEHT+MTX:0.056±0.025, p<0.01). The basic expression of H19 was significantly lower in 4T07 tumors compared to the more aggressive 4T1 tumors (4T07:0.006±0.004 vs 4T1:0.399±0.071, p<0.0001). In 4T07 tumors H19 expression did not change after three mEHT treatments (sham:0.404±0.334 vs mEHT:1.391±1.840, p>0.10) compared to the sham group.ConclusionOur results demonstrate, that modulated electro‐hyperthermia can reduce the expression of tumor promoting H19 lncRNA in vitro and in vivo both in monotherapy and in combination with chemotherapy. Our findings suggest, that mEHT as an alternative complementary treatment could promote antitumor therapy by inhibiting the tumor progression mediating H19 lncRNA expression. More effective therapy against the more aggressive 4T1 line may be related to higher baseline expression and more significant effect on H19.Support or Funding InformationGrantNVKP_16‐1‐2016‐0042, EFOP‐3.6.3‐VEKOP‐16‐2017‐00009

Analysis of the effects of mEHT on the treatment-related toxicity and quality of life of HIV-positive cervical cancer patients

Introduction HIV infection is associated with increased treatment-related toxicity and worse outcomes in locally advanced cervical cancer patients (LACC), especially in resource-constrained settings. Local control (LC) in a phase III randomized, controlled trial investigating modulated electro-hyperthermia (mEHT) on LACC patients in South Africa (ethics registration: M120477/M190295), was significantly higher in participants randomized to receive chemoradiotherapy (CRT) with mEHT compared to CRT alone (stratum: HIV status, accounting for age and stage). This analysis investigates whether mEHT adds to the toxicity profile of CRT in HIV-positive LACC participants. Methods Inclusion criteria: signed informed consent; International Federation of Gynecology and Obstetrics stages IIB to IIIB squamous cell carcinoma of the cervix; HIV-positive patients: CD4 count >200 cell/µL/on antiretroviral treatment for >6 months; eligible for CRT with radical intent. Recruitment: January 2014 to November 2017 (ClinicalTrials.gov: NCT03332069). Acute toxicity (evaluated using CTCAE v4 criteria) and quality of life (according to EORTC forms) in 206 participants randomized for treatment were evaluated alongside the LC results to determine safety and efficacy in HIV-positive participants. Results Compliance to mEHT treatment was high (97% completed ≥8 treatments) with no significant differences in CRT-related toxicity between treatment groups or between HIV-positive and -negative participants. Adverse events attributed to mEHT were minor, even in obese patients, and did not affect CRT compliance. Participants treated with mEHT reported improved fatigue, pain, emotional and cognitive functioning. Conclusion mEHT did not cause unexpected CRT-related toxicities and is a safe treatment modality for HIV-positive patients, with minor limitations regarding body weight, even in a low-resource setting.

EP1.01-39 A Randomised Phase II Trial of Vitamin C Synergy with Hyperthermia in Patients with Advanced Non-Small-Cell Lung Cancer

Intravenous vitamin C (IVC) and modulated electrohyperthermia (mEHT) are widely used by integrative cancer practitioners for many years. However, there are no sufficient data in quality of life (QoL), clinical response and survival time of the above treatments in patients with stage III-IV Non-Small Cell Lung Cancer (NSCLC). Our phase I clinical trial proved that IVC simultaneously with mEHT were safe for NSCLC patients. A randomised phase II controlled trial was performed to compare supportive care with and without IVC + mEHT concomitant treatment (In the active arm: patients were allocated into 1 g/kg d, 1.2 g/kg d, 1.5 g/kg d dosage groups simultaneously with mEHT, three times a week for 25 treatments in total)on tumour size, progression-free survival (PFS) and overall survival (OS) in advanced Chinese NSCLC patients. Subsequently, 97 patients were analysed at the data cut-off (17th July, 2018). Enhanced chest and abdomen CT scans, brain MRI and bone scans were carried out at baseline, and every 4 weeks for the first 12 weeks from the start of the study. Response measurements were carried out according to RECIST 1.1. 3 month disease control rate(DCR) was measured 3 months after the therapy and defined as the percentage of subjects with complete response (CR), partial response (PR) or stable disease (SD) at 3 months relative to all randomly assigned patients. After a median follow up of 10 months, both the PFS and OS were significantly improved by IVC + mEHT compared to control (PFS: 3 month vs. 1.85 months, P<0.05; OS: 12 months vs. 7.5 months, P<0.05). The average scores for the functioning scales increased continuously, so that the QoL improved in the active arm despite the advanced stage of the disease(P<0.05). 3-month DCR after treatment was 42.9% in the active arm and 16.7% in the control arm (P<0.05). Both interleukin-6 and c-reactive protein were significantly decrease after treatments in active arm in comparison with control arm (P<0.05). However, there were no significant differences in 3 month DCR, PFS and OS between the three groups with different applied dosages of vitamin C. No significant differences were observed between parameters of adenocarcinoma and squamous cell carcinoma and between EGFR(+) and EGFR(–). IVC + mEHT treatment significantly improves QoL, prolongs PFS and OS, and moderates cancer-related inflammation, and so is a feasible treatment for patients with advanced NSCLC. This trial is registered in ClinicalTrials.gov (ID: NCT02655913).

Stress-Induced, p53-Mediated Tumor Growth Inhibition of Melanoma by Modulated Electrohyperthermia in Mouse Models without Major Immunogenic Effects.

Modulated electrohyperthermia (mEHT), an innovative complementary technique of radio-, chemo-, and targeted oncotherapy modalities, can induce tumor apoptosis and contribute to a secondary immune-mediated cancer death. Here, we tested the efficiency of high-fever range (~42 °C) mEHT on B16F10 melanoma both in cell culture and allograft models. In vivo, mEHT treatment resulted in significant tumor size reduction when repeated three times, and induced major stress response as indicated by upregulated cytoplasmic and cell membrane hsp70 levels. Despite the increased PUMA and apoptosis-inducing factor 1, and moderate rise in activated-caspase-3, apoptosis was not significant. However, phospho-H2AX indicated DNA double-strand breaks, which upregulated p53 protein and its downstream cyclin-dependent kinase inhibitors p21waf1 and p27kip. Combined in vitro treatment with mEHT and the p53 activator nutlin-3a additively reduced cell viability compared to monotherapies. Though mEHT promoted the release of damage-associated molecular pattern (DAMP) damage signaling molecules hsp70, HMGB1 and ATP to potentiate the tumor immunogenicity of melanoma allografts, it reduced MHC-I and melan-A levels in tumor cells. This might explain why the number of cytotoxic T cells was moderately reduced, while the amount of natural killer (NK) cells was mainly unchanged and only macrophages increased significantly. Our results suggest that mEHT-treatment-related tumor growth control was primarily mediated by cell-stress-induced p53, which upregulated cyclin-dependent kinase inhibitors. The downregulated tumor antigen-presenting machinery may explain the reduced cytotoxic T-cell response despite increased DAMP signaling. Decreased tumor antigen and MHC-I levels suggest that natural killer (NK) cells and macrophages were the major contributors to tumor eradication.

Modulated electro hyperthermia inhibits tumor progression in a triple negative mouse breast cancer model

IntroductionThe effective therapy of triple‐negative breast cancer (TNBC) has not yet been achieved. Modulated electro‐hyperthermia (mEHT) is a novel adjuvant antitumor therapy, based on the highly selective heating of the tumor tissue by a 13.56 MHz radiofrequency current induced electric field.AimsOur aim was to investigate the effects of repeated mEHT treatment in a triple‐negative mammary carcinoma bearing mouse model.Method4T07 cells were inoculated orthotopically in female BALB/c mice. Tumor growth was monitored in vivo by digital caliper and ultrasound (Phillips Sonos 5500). The mEHT (n=8) or sham (n=9) treatments started 7 days after inoculation and were repeated 5 times, on every other day. Mice were euthanized 1 day after the fifth treatment and the tumors were dissected, weighed and processed for histology and molecular biology techniques. The ratio of the damaged area compared to the whole tumor area (Tissue Destruction Ratio, TDR) was evaluated on H&amp;E and cleaved caspase‐3 stained sections, while HSP70, a common damage‐associated molecular signal, Ki67, a proliferation marker and p21, a tumor suppressor protein expression were analyzed on immunohistochemical staining with the HistoQuant module of the CaseViewer Software (3DHistech).ResultsThere was a significant decrease in tumor growth (sham: 5.7x, mEHT: 2.4x relative to pre‐treatment (day 6) size, p&lt;0.0001) and weight (sham: 288.3±58.1 mg vs mEHT: 85.3±21.3 mg, p&lt;0.05) in the mEHT treated group, compared to the sham group. The HSP70 stained area in the non‐destructed tumor tissue was 5.2 fold higher in the mEHT treated group, compared to the sham group (p&lt;0.05). Moreover, the Ki67 positive nucleus / mm2 count was significantly lower (sham: 2823.4±211.9 pcs/mm2 vs mEHT: 1736.7±315.3 pcs/mm2, p&lt;0.05) and the p21 positive nucleus / mm2 count showed increasing tendency (sham: 127.0±25.3 pcs/mm2 vs mEHT: 242.2±78.2 pcs/mm2, p = 0,073) in the mEHT treated group, compared to the sham group.ConclusionOur findings suggest, that repeated mEHT could lower tumor cell proliferation by promoting cell cycle arrest in vivo. Thus, mEHT could be a possible alternative adjuvant therapeutic strategy for TNBC cancer patients. We plan next generation sequencing to elucidate the biological mechanism behind the effects of mEHT.NVKP_16‐1‐2016‐0042This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Modulated electro-hyperthermia-enhanced liposomal drug uptake by cancer cells.

PurposeModulated electro-hyperthermia (mEHT) stands to be a significant technological advancement in the hyperthermia field, utilizing autofocusing electromagnetic power on the cell membrane to create massive apoptosis. Since mEHT possesses the unique ability to excite cell membranes, we hypothesized that mEHT could enhance the uptake of liposomal drugs by enhancing phagocytic activity.Materials and methodsWater bath control and mEHT were used to compare the enhancement of liposome-encapsulated doxorubicin (Lipodox®) uptake by cancer cells. Cancer cells were made visible by doxorubicin fluorescence to investigate drug uptake. Viable cell yield was determined via the Trypan Blue exclusion method. Various substrates were used to investigate the mechanism of drug-uptake enhancement. The murine colon carcinoma model, CT26, was used to confirm the tissue infiltration of Lipodox® and its therapeutic effect.ResultsmEHT treatment showed a significant enhancement of Lipodox® uptake of doxorubicin fluorescence compared with 37°C or 42°C water bath treatment. Tumor tissue sections also confirmed that mEHT treatment achieved the highest doxorubicin concentration in vivo (1.44±0.32 µg/g in mEHT group and 0.79±0.32 µg/g in 42°C water bath). Wortmannin was used to inhibit the macropinocytosis effect and 70 kDa dextran-FITC served as uptake substance. The uptake of dextran-FITC by cancer cells significantly increased after mEHT treatment whereas such enhancement was significantly inhibited by wortmannin.ConclusionThe result showed mEHT-induced particle-uptake through macropinocytosis. mEHT-enhanced uptake of Lipodox® may amplify the therapeutic effect of liposomal drugs. This novel finding warrants further clinical investigation.

Modulated Electro-Hyperthermia as Palliative Treatment for Pancreatic Cancer: A Retrospective Observational Study on 106 Patients

Background: Pancreatic adenocarcinoma has a poor prognosis, resulting in a <10% survival rate at 5 years. Modulated electro-hyperthermia (mEHT) has been increasingly used for pancreatic cancer palliative care and therapy. Objective: To monitor the efficacy and safety of mEHT for the treatment of advanced pancreatic cancer. Methods: We collected data retrospectively on 106 patients affected by stage III-IV pancreatic adenocarcinoma. They were divided into 2 groups: patients who did not receive mEHT (no-mEHT) and patients who were treated with mEHT. We performed mEHT applying a power of 60 to 150 W for 40 to 90 minutes. The mEHT treatment was associated with chemotherapy and/or radiotherapy for 33 (84.6%) patients, whereas 6 (15.4%) patients received mEHT alone. The patients of the no-mEHT group received chemotherapy and/or radiotherapy in 55.2% of cases. Results: Median age of the sample was 65.3 years (range = 31-80 years). After 3 months of therapy, the mEHT group had partial response in 22/34 patients (64.7%), stable disease in 10/34 patients (29.4%), and progressive disease in 2/34 patients (8.3%). The no-mEHT group had partial response in 3/36 patients (8.3%), stable disease in 10/36 patients (27.8%), and progressive disease in 23/36 patients (34.3%). The median overall survival of the mEHT group was 18.0 months (range = 1.5-68.0 months) and 10.9 months (range = 0.4-55.4 months) for the non-mEHT group. Conclusions: mEHT may improve tumor response and survival of pancreatic cancer patients.

Combined treatment with modulated electro-hyperthermia and an autophagy inhibitor effectively inhibit ovarian and cervical cancer growth

Purpose: Modulated electro-hyperthermia (mEHT), known as oncothermia, is an anticancer therapy that induces radiofrequency thermal damage to the cancer tissues. This study aimed to evaluate the potential effectiveness of mEHT as a therapeutic tool in ovarian and cervical cancer.Materials and methods: We used both tumor-bearing mice and ovarian and cervical OVCAR-3, SK-OV-3, HeLa and SNU-17 cancer cell lines to investigate the effects of mEHT in vivo and in vitro, respectively, and determine whether it was enhanced by cotreatment with an autophagy inhibitor.Results: We discovered that phosphorylation of p38, a stress-dependent kinase, was induced at the Thr180/Tyr182 residue in cancer cells exposed to mEHT. Apoptotic markers such as cleaved caspase-3 and poly-ADP ribose polymerase (PARP) were increased in OVCAR-3 and SNU-17 cells. Fluorescence-activated cell sorting (FACS) analysis showed a significant increase in the population of sub-G1 mEHT-exposed cells, which are dying and apoptotic cells. mEHT also reduced both weight and volume of xenograft tumors in mice transplanted with ovarian and cervical cancer cells and patient-derived cancer tissues. We determined that mEHT-induced cellular damage recovery was mediated by autophagy and, therefore, expectedly, cotreatment with mEHT and 3-methyladenine (3-MA), an autophagy inhibitor, more effectively inhibited cancer cell growth than individual treatment did.Conclusions: mEHT treatment alone was sufficient to inhibit cancer growth, while a combined treatment with mEHT and an autophagy inhibitor amplified this inhibition effect.

Abstract 196: The effect of modulated electro-hyperthermia on B16-F10 melanoma tumor growth

Abstract The objective of the present study was to examine the effect of modulated electro-hyperthermia (mEHT) on B16-F10 mouse melanoma cell line in vitro and in vivo. mEHT induces tumor-selective heat shock at ~42°C and is used as adjuvant to conventional cancer therapy. For in vitro comparison of the effect of mEHT to conventional hyperthermia (convHT), cells grown on coverslips were treated using mEHT or convHT in water-bath at 42°C for 1x60 min. Changes in gene expression, viability and invasiveness were measured. For in vivo studies, B16-F10 cells mixed with Matrigel were injected subcutaneously into C57Bl/6 mice as the tumors were exposed to 42°C for 30 minutes with mEHT every second day for three times. Tumors were removed 48 hours post treatment, weighed and digested to single-cell suspension. The supernatant of tumor cells and the plasma of tumor-bearing mice were used to screen a membrane-based antibody array representing a panel of 111 cytokines. The tumor cells were stained for flow cytometry to determine the changes induced on melanoma cells and tumor-infiltrating leukocytes. As a marker of in vitro treatment we measured HSPA2 expression with qPCR. Similar expression patterns were induced both by mEHT and convHT. Three hours after treatment the peak levels of HSPA2 were 3 times higher as compared to the untreated control in a time-course experiment. Next, we showed that in parallel to the upregulation of proapoptotic genes Puma, Bak-1 and Bax, downregulation of prosurvival genes XIAP, Bcl-2, Bcl-XL was induced both by convHT and mEHT with similar kinetics and magnitude. Furthermore, cell viability decreased and the invasivness was impaired as measured by scratch assay by both treatment types. The in vivo mEHT of primary melanoma tumors resulted in considerable tumor size reduction. Flow cytometry analysis revealed the increase of MHC class I on the surface of melanoma cells and concomitant activation of CD8+ cytotoxic T lymphocytes in response to treatment. Increased number of CD4+ T cells and Gr1+ granulocytes was detected, although changes in the various subpopulations need further analysis. F4/80+CD11b+ macrophages and mature DC-s were slightly elevated in the treated tumors. The cytokine array analysis shows that several cytokines responsible for leukocyte recruitment were enriched in the treated tumor (SDF-1, osteopontin, IL-1). Complement activation was induced by mEHT both in the tumor microenvironment and the plasma, indicating an acute inflammatory response to treatment. Furthermore, along the short pentraxins, CRP and SAP, the long pentraxin PTX3 was elevated in the tumor and plasma of the treated mice, suggesting that mEHT induced the tumor clearance. Taken together, our results demonstrate that in vitro mEHT and convHT produce comparable effects, whereas the in vivo mEHT treatment was effective in reducing the tumor size by enhancing immune recognition of B16-F10. This study was supported by NVKP 16-1- 2016-0042 grant. Citation Format: Balázs Besztercei, Enikő Major, Anett Benedek, Zoltán Benyó, Andrea Balogh. The effect of modulated electro-hyperthermia on B16-F10 melanoma tumor growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 196.

Modulated electro-hyperthermia induced loco-regional and systemic tumor destruction in colorectal cancer allografts.

Background: Modulated electro-hyperthermia (mEHT), a non-invasive intervention using 13.56 MHz radiofrequency, can selectively target cancers due to their elevated glycolysis (Warburg-effect), extracellular ion concentration and conductivity compared to normal tissues. We showed earlier that mEHT alone can provoke apoptosis and damage associated molecular pattern (DAMP) signals in human HT29 colorectal cancer xenografts of immunocompromised mice.Materials: Here we tested the mEHT induced stress and immune responses in C26 colorectal cancer allografts of immunocompetent (BALB/c) mice between 12-72 h post-treatment. The right side of the symmetrical tumors grown in both femoral regions of mice were treated for 30 minutes, while the left side tumors served for untreated controls.Results: Loco-regional mEHT treatment induced an ongoing and significant tumor damage with the blockade of cell cycle progression indicated by the loss of nuclear Ki67 protein. Nuclear shrinkage, apoptotic bodies and DNA fragmentation detected using TUNEL assay confirmed apoptosis. Cleaved/activated-caspase-8 and -caspase-3 upregulation along with mitochondrial translocation of bax protein and release of cytochrome-c were consistent with the activation of both the extrinsic and intrinsic caspase-dependent programmed cell death pathways. The prominent release of stress-associated Hsp70, calreticulin and HMGB1 proteins, relevant to DAMP signaling, was accompanied by the significant tumor infiltration by S100 positive antigen presenting dendritic cells and CD3 positive T-cells with only scant FoxP3 positive regulatory T-cells. In addition, mEHT combined with a chlorogenic acid rich T-cell promoting agent induced significant cell death both in the treated and the untreated contralateral tumors indicating a systemic anti-tumor effect.Conclusions: mEHT induced caspase-dependent programmed cell death and the release of stress associated DAMP proteins in colorectal cancer allografts can provoke major immune cell infiltration. Accumulating antigen presenting dendritic cells and T-cells are likely to contribute to the ongoing tumor destruction by an immunogenic cell death mechanism both locally and through systemic effect at distant tumor sites.

Effect of Modulated Electrohyperthermia on the Pharmacokinetics of Oral Transmucosal Fentanyl Citrate in Healthy Volunteers

PurposeThis study aimed to determine whether changes occur in fentanyl absorption and disposition when administered in conjunction with modulated electrohyperthermia (mEHT) treatment. MethodsA randomized, single-dose, crossover, open-label study was used to investigate the effect of mEHT on the pharmacokinetic properties of fentanyl in 12 healthy volunteers. The 12 healthy volunteers were each administered a single dose of oral transmucosal fentanyl citrate (OTFC) or a single dose of OTFC with mEHT. mEHT was performed on the abdomen for 1 hour. Blood samples were collected for 24 hours after dosing. The temperature of the abdominal skin surface was assessed before dosing and at 10, 20, and 60 minutes after dosing. FindingsGeometric mean ratios (ratio of fentanyl with mEHT to fentanyl alone) for the Cmax and AUC0–last were 1.20 (90% CI, 1.09–1.32) and 1.15 (90% CI, 0.99–1.33), respectively. The mean temperature of the abdominal skin surface increased by approximately 4°C. ImplicationsThere was an increase in the overall exposure to the drug without implications of any clinical significance. OTFC can be administered without limitations in combination with mEHT, and it is not necessary to modify the dosing regimen. cris.nih.go,kr Identifier: KCT0001286.

Comparison of biological effects of modulated electro-hyperthermia and conventional heat treatment in human lymphoma U937 cells.

Loco-regional hyperthermia treatment has long history in oncology. Modulated electro-hyperthermia (mEHT, trade name: oncothermia) is an emerging curative treatment method in this field due to its highly selective actions. The impedance-matched, capacitive-coupled modulated radiofrequency (RF) current is selectively focused in the malignant cell membrane of the cancer cells. Our objective is studying the cell-death process and comparing the cellular effects of conventional water-bath hyperthermia treatment to mEHT. The U937 human histiocytic lymphoma cell line was used for the experiments. In the case of conventional hyperthermia treatment, cells were immersed in a thermoregulated water bath, whereas in the case of mEHT, the cells were treated using a special RF generator (LabEHY, Oncotherm) and an applicator. The heating dynamics, the maximum temperature reached (42 °C) and the treatment duration (30 min) were exactly the same in both cases. Cell samples were analysed using different flow cytometric methods as well as microarray gene expression assay and western blot analysis was also used to reveal the molecular basis of the induced effects. Definite difference was observed in the biological response to different heat treatments. At 42 °C, only mEHT induced significant apoptotic cell death. The GeneChip analysis revealed a whole cluster of genes, which are highly up-regulated in case of only RF heating, but not in conventional heating. The Fas, c-Jun N-terminal kinases (JNK) and ERK signalling pathway was the dominant factor to induce apoptotic cell death in mEHT, whereas the cell-protective mechanisms dominated in case of conventional heating. This study has clearly shown that conventional hyperthermia and RF mEHT can result in different biological responses at the same temperature. The reason for the difference is the distinct, non-homogenous energy distribution on the cell membrane, which activates cell death-related signalling pathways in mEHT treatment but not in conventional heat treatment.

Modulated electro-hyperthermia enhances dendritic cell therapy through an abscopal effect in mice.

The aim of this study was to assess whether modulated electro-hyperthermia (mEHT) can induce an abscopal effect and thereby enhance the antitumor effects of immunotherapy. We used an intratumoral dendritic cell (DC) injection and mEHT to treat C3H/He mice inoculated with squamous cell carcinoma SCCVII cells in the left leg, and we assessed the whole body antitumor effects. Tumors were examined every two or three days in order to assess growth inhibition. The tumor-draining lymph nodes were removed to enable flow cytometric analysis of CD3+ and CD8+ cells, whereas immunohistochemistry was used to assess CD8, S100 and Foxp3 expression in the tumors. Additionally, GP96 expression in the tumors from the different treatment groups was measured. In the control group, the mean tumor volume was larger than that in other groups. These results indicated that the combination therapy of an intratumoral DC injection and mEHT evoked systemic antitumor activity. A larger number of CD3+ and CD8+ cells were detected by flow cytometric analysis in the DC plus mEHT treatment group. Tumor tissue immunostaining showed that CD8 and S100 were more strongly expressed in the DC plus mEHT treatment group, although Foxp3 expression was much higher in the control group. The GP96 gene expression level in the mEHT group was significantly different from the expression level in the control group. An abscopal effect may be induced by mEHT, and the effect of immunotherapy with DCs was strongly enhanced by the overexpression of GP96. GP96 is thought to be one of the molecules explaining the abscopal effect. Direct intratumoral administration of DCs and mEHT may be a feasible future treatment strategy.