Strong synergy of heat and modulated electromagnetic field in tumor cell killing

Targeting the heat shock response induced by modulated electro-hyperthermia (mEHT) in cancer

The Heat Shock Response (HSR) is a cellular stress reaction crucial for cell survival against stressors, including heat, in both healthy and cancer cells. Modulated electro-hyperthermia (mEHT) is an emerging non-invasive cancer therapy utilizing electromagnetic fields to selectively target cancer cells via temperature-dependent and independent mechanisms. However, mEHT triggers HSR in treated cells. Despite demonstrated efficacy in cancer treatment, understanding the underlying molecular mechanisms for improved therapeutic outcomes remains a focus. This review examines the HSR induced by mEHT in cancer cells, discussing potential strategies to modulate it for enhanced tumor-killing effects. Approaches such as HSF1 gene-knockdown and small molecule inhibitors like KRIBB11 are explored to downregulate the HSR and augment tumor destruction. We emphasize the impact of HSR inhibition on cancer cell viability, mEHT sensitivity, and potential synergistic effects, addressing challenges and future directions. This understanding offers opportunities for optimizing treatment strategies and advancing precision medicine in cancer therapy.

“Cold” colorectal cancer faces a bottleneck in immunotherapy

The advent of immunotherapy and the development of immune checkpoint inhibitors (ICIs) are changing the way we think about cancer treatment. ICIs have shown clinical benefits in a variety of tumor types, and ICI-based immunotherapy has shown effective clinical outcomes in immunologically “hot” tumors. However, for immunologically “cold” tumors such as colorectal cancer (CRC), only a limited number of patients are currently benefiting from ICIs due to limitations such as individual differences and low response rates. In this review, we discuss the classification and differences between hot and cold CRC and the current status of research on cold CRC, and summarize the treatment strategies and challenges of immunotherapy for cold CRC. We also explain the mechanism, biology, and role of immunotherapy for cold CRC, which will help clarify the future development of immunotherapy for cold CRC and discovery of more emerging strategies for the treatment of cold CRC.

Radiofrequency Electromagnetic Fields Cause Non-Temperature-Induced Physical and Biological Effects in Cancer Cells

Simple Summary

Radiofrequency electromagnetic fields are used for tumor heating as adjunct therapy, but it appears that sufficient temperatures can sometimes not be reached. We therefore aimed to study potential non-temperature-induced anticancer effects when adding amplitude modulation to the radiofrequency waves. We could demonstrate in a colorectal cancer model that radiofrequency electromagnetic fields do have anticancer effects when not being induced by increased temperature that can be further increased by amplitude modulation. Therefore, this treatment could potentially serve as a more effective tumor therapy.

Abstract

Non-temperature-induced effects of radiofrequency electromagnetic fields (RF) have been controversial for decades. Here, we established measurement techniques to prove their existence by investigating energy deposition in tumor cells under RF exposure and upon adding amplitude modulation (AM) (AMRF). Using a preclinical device LabEHY-200 with a novel in vitro applicator, we analyzed the power deposition and system parameters for five human colorectal cancer cell lines and measured the apoptosis rates in vitro and tumor growth inhibition in vivo in comparison to water bath heating. We showed enhanced anticancer effects of RF and AMRF in vitro and in vivo and verified the non-temperature-induced origin of the effects. Furthermore, apoptotic enhancement by AM was correlated with cell membrane stiffness. Our findings not only provide a strategy to significantly enhance non-temperature-induced anticancer cell effects in vitro and in vivo but also provide a perspective for a potentially more effective tumor therapy.

Long-Term Feasibility of 13.56 MHz Modulated Electro-Hyperthermia-Based Preoperative Thermoradiochemotherapy in Locally Advanced Rectal Cancer

Simple Summary

We demonstrated that a 13.56 MHz modulated electro-hyperthermia (mEHT) boost is feasible in neoadjuvant treatment for rectal cancer. Herein, we attempted to present the long-term results for this phase 2 trial. Although there are many reports on the usefulness of thermoradiochemotherapy for loco-regional control, so far, only a few cases of survival benefit exist. Thus, this study assessed whether this limitation of hyperthermia could be overcome through the mEHT method featuring an applied energy variable. Following a median follow-up of 58 months for 60 patients, mEHT boost showed comparable results with conventional hyperthermia; potential therapeutic effects were also observed. Moreover, mEHT could be considered a useful tool in combination treatment with radiotherapy owing to its low thermotoxicity and improved treatment compliance.

Abstract

We evaluated the effect of 13.56 MHz modulated electro-hyperthermia (mEHT) boost in neoadjuvant treatment for cT3-4- or cN-positive rectal cancer. Sixty patients who completed the mEHT feasibility trial (ClinicalTrials.gov Identifier: NCT02546596) were analyzed. Whole pelvis radiotherapy of 40 Gy, mEHT boost twice a week during radiotherapy, and surgical resection 6–8 weeks following radiotherapy were performed. The median age was 59. The median follow-up period was 58 (6–85) months. Total/near total tumor regression was observed in 20 patients (33.3%), including nine cases of complete response. T- and N-downstaging was identified in 40 (66.6%) and 53 (88.3%) patients, respectively. The 5-year overall and disease-free survival were 94.0% and 77.1%, respectively. mEHT energy of ≥3800 kJ potentially increased the overall survival (p = 0.039). The ypN-stage and perineural invasion were possible significant factors in disease-free (p = 0.003 and p = 0.005, respectively) and distant metastasis-free (p = 0.011 and p = 0.034, respectively) survival. Tumor regression, resection margin status, and other molecular genetic factors showed no correlation with survival. Although a limited analysis of a small number of patients, mEHT was feasible considering long-term survival. A relatively low dose irradiation (40 Gy) plus mEHT setting could ensure comparable clinical outcomes with possible mEHT-related prognostic features.

Heterogeneous Heat Absorption Is Complementary to Radiotherapy

Simple Summary

This review shows the advantages of heterogeneous heating of selected malignant cells in harmonic synergy with radiotherapy. The main clinical achievement of this complementary therapy is its extreme safety and minimal adverse effects. Combining the two methods opens a bright perspective, transforming the local radiotherapy to the antitumoral impact on the whole body, destroying the distant metastases by “teaching” the immune system about the overall danger of malignancy.

Abstract

(1) Background: Hyperthermia in oncology conventionally seeks the homogeneous heating of the tumor mass. The expected isothermal condition is the basis of the dose calculation in clinical practice. My objective is to study and apply a heterogenic temperature pattern during the heating process and show how it supports radiotherapy. (2) Methods: The targeted tissue’s natural electric and thermal heterogeneity is used for the selective heating of the cancer cells. The amplitude-modulated radiofrequency current focuses the energy absorption on the membrane rafts of the malignant cells. The energy partly “nonthermally” excites and partly heats the absorbing protein complexes. (3) Results: The excitation of the transmembrane proteins induces an extrinsic caspase-dependent apoptotic pathway, while the heat stress promotes the intrinsic caspase-dependent and independent apoptotic signals generated by mitochondria. The molecular changes synergize the method with radiotherapy and promote the abscopal effect. The mild average temperature (39–41 °C) intensifies the blood flow for promoting oxygenation in combination with radiotherapy. The preclinical experiences verify, and the clinical studies validate the method. (4) Conclusions: The heterogenic, molecular targeting has similarities with DNA strand-breaking in radiotherapy. The controlled energy absorption allows using a similar energy dose to radiotherapy (J/kg). The two therapies are synergistically combined.

Effects of Modulated Electro-Hyperthermia (mEHT) on Two and Three Year Survival of Locally Advanced Cervical Cancer Patients

(1) Background: Modulated electro-hyperthermia (mEHT) is a mild to moderate, capacitive-coupled heating technology that uses amplitude modulation to enhance the cell-killing effects of the treatment. We present three year survival results and a cost effectiveness analysis from an ongoing randomised controlled Phase III trial involving 210 participants evaluating chemoradiotherapy (CRT) with/without mEHT, for the management of locally advanced cervical cancer (LACC) in a resource constrained setting (Ethics Approval: M120477/M704133; ClinicalTrials.gov ID: NCT033320690). (2) Methods: We report hazard ratios (HR); odds ratio (OR), and 95% confidence intervals (CI) for overall survival and disease free survival (DFS) at two and three years in the ongoing study. Late toxicity, quality of life (QoL), and a cost effectiveness analysis (CEA) using a Markov model are also reported. (3) Results: Disease recurrence at two and three years was significantly reduced by mEHT (HR: 0.67, 95%CI: 0.48-0.93, p = 0.017; and HR: 0.70, 95%CI: 0.51-0.98, p = 0.035; respectively). There were no significant differences in late toxicity between the groups, and QoL was significantly improved in the mEHT group. In the CEA, mEHT + CRT dominated the model over CRT alone. (4) Conclusions: CRT combined with mEHT improves QoL and DFS rates, and lowers treatment costs, without increasing toxicity in LACC patients, even in resource-constrained settings.

External Basic Hyperthermia Devices for Preclinical Studies in Small Animals

Simple Summary

The application of mild hyperthermia can be beneficial for solid tumor treatment by induction of sublethal effects on a tissue- and cellular level. When designing a hyperthermia experiment, several factors should be taken into consideration. In this review, multiple elementary hyperthermia devices are described in detail to aid standardization of treatment design.

Abstract

Preclinical studies have shown that application of mild hyperthermia (40–43 °C) is a promising adjuvant to solid tumor treatment. To improve preclinical testing, enhance reproducibility, and allow comparison of the obtained results, it is crucial to have standardization of the available methods. Reproducibility of methods in and between research groups on the same techniques is crucial to have a better prediction of the clinical outcome and to improve new treatment strategies (for instance with heat-sensitive nanoparticles). Here we provide a preclinically oriented review on the use and applicability of basic hyperthermia systems available for solid tumor thermal treatment in small animals. The complexity of these techniques ranges from a simple, low-cost water bath approach, irradiation with light or lasers, to advanced ultrasound and capacitive heating devices.

Beneficial effects of modulated electro-hyperthermia during neoadjuvant treatment for locally advanced rectal cancer

PURPOSE

Modulated electro-hyperthermia (mEHT) may enhance the tumor response, although the effectiveness of combined neoadjuvant therapy remains unclear. Therefore, we investigated the role of mEHT with neoadjuvant therapy for locally advanced rectal cancer.

MATERIALS AND METHODS

Clinical data were analyzed for 120 patients who received neoadjuvant treatment for locally advanced rectal cancer (T3/4 or N+, M0) from May 2012 to December 2017. Capecitabine or 5-fluorouracil was administered along with radiotherapy. Patients were categorized into mEHT group (62 patients) and non-mEHT group (58 patients) depending on whether mEHT was added. Surgery was performed 6-8 weeks after the end of radiotherapy.

RESULTS

The median age was 59 years (range, 33-83). The median radiation dose was significantly less for mEHT group (40 Gy) than for non-mEHT group (50.4 Gy). In mEHT group, 80.7% showed down-staging compared with 67.2% in non-mEHT group. For large tumors of more than 65 cm³ (mean), improved tumor regression was observed in 31.6% of mEHT group compared with 0% of non-mEHT group (p = .024). The gastrointestinal toxicity rate of mEHT group was 64.5%, which was found to be statistically significantly less than 87.9% of non-mEHT group (p = .010). The 2-year disease-free survival was 96% for mEHT group and 79% for non-mEHT group (p = .054).

CONCLUSION

The overall mEHT group had a comparable response and survival using less radiation dosing compared with standard care; the subgroup with large tumors showed improved efficacy for tumor regression after mEHT.

Non-thermal membrane effects of electromagnetic fields and therapeutic applications in oncology

The temperature-independent effects of electromagnetic fields (EMF) have been controversial for decades. Here, we critically analyze the available literature on non-thermal effects of radiofrequency (RF) and microwave EMF. We present a literature review of preclinical and clinical data on non-thermal antiproliferative effects of various EMF applications, including conventional RF hyperthermia (HT, cRF-HT). Further, we suggest and evaluate plausible biophysical and electrophysiological models to decipher non-thermal antiproliferative membrane effects. Available preclinical and clinical data provide sufficient evidence for the existence of non-thermal antiproliferative effects of exposure to cRF-HT, and in particular, amplitude modulated (AM)-RF-HT. In our model, transmembrane ion channels function like RF rectifiers and low-pass filters. cRF-HT induces ion fluxes and AM-RF-HT additionally promotes membrane vibrations at specific resonance frequencies, which explains the non-thermal antiproliferative membrane effects via ion disequilibrium (especially of Ca²⁺) and/or resonances causing membrane depolarization, the opening of certain (especially Ca²⁺) channels, or even hole formation. AM-RF-HT may be tumor-specific owing to cancer-specific ion channels and because, with increasing malignancy, membrane elasticity parameters may differ from that in normal tissues. Published literature suggests that non-thermal antiproliferative effects of cRF-HT are likely to exist and could present a high potential to improve future treatments in oncology.

A Potential Bioelectromagnetic Method to Slow Down the Progression and Prevent the Development of Ultimate Pulmonary Fibrosis by COVID-19

Introduction

Right now, we are facing a global pandemic caused by the coronavirus SARS-CoV-2 that causes the highly contagious human disease COVID-19. The number of COVID-19 cases is increasing at an alarming rate, more and more people suffer from it, and the death toll is on the rise since December 2019, when COVID-19 has presumably appeared. We need an urgent solution for the prevention, treatment, and recovery of the involved patients.

Methods

Modulated electro-hyperthermia (mEHT) is known as an immuno-supportive therapy in oncology. Our proposal is to apply this method to prevent the progression of the disease after its identification, to provide treatment when necessary, and deliver rehabilitation to diminish the fibrotic-often fatal-consequences of the infection.

Hypothesis

The effects of mEHT, which are proven for oncological applications, could be utilized for the inactivation of the virus or for treating the fibrotic consequences. The hypothesized mEHT effects, which could have a role in the antiviral treatment, it could be applied for viral-specific immune-activation and for anti-fibrotic treatments.

Modulated Electrohyperthermia: A New Hope for Cancer Patients

According to the World Health Organization, the prevalence of cancer has increased worldwide. Oncological hyperthermia is a group of methods that overheat the malignant tissues locally or systematically. Nevertheless, hyperthermia is not widely accepted, primarily because of the lack of selectivity for cancer cells and because the temperature-triggered higher blood flow increases the nutrient supply to the tumor, raising the risk of metastases. These problems with classical hyperthermia led to the development of modulated electrohyperthermia (mEHT). The biophysical differences of the cancer cells and their healthy hosts allow for selective energy absorption on the membrane rafts of the plasma membrane of the tumor cells, triggering immunogenic cell death. Currently, this method is used in only 34 countries. The effectiveness of conventional oncotherapies increases when it is applied in combination with mEHT. In silico, in vitro, and in vivo preclinical research studies have all shown the extraordinary ability of mEHT to kill malignant cells. Clinical applications have improved the quality of life and the survival of patients. For these reasons, many other research studies are presently in progress worldwide. Thus, the objective of this review is to highlight the capabilities and advantages of mEHT and provide new hopes for cancer patients worldwide.

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.

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 Summary

Breast 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.

Abstract

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.

Quo Vadis Oncological Hyperthermia (2020)?

Heating as a medical intervention in cancer treatment is an ancient approach, but effective deep heating techniques are lacking in modern practice. The use of electromagnetic interactions has enabled the development of more reliable local-regional hyperthermia (LRHT) techniques whole-body hyperthermia (WBH) techniques. Contrary to the relatively simple physical-physiological concepts behind hyperthermia, its development was not steady, and it has gone through periods of failures and renewals with mixed views on the benefits of heating seen in the medical community over the decades. In this review we study in detail the various techniques currently available and describe challenges and trends of oncological hyperthermia from a new perspective. Our aim is to describe what we believe to be a new and effective approach to oncologic hyperthermia, and a change in the paradigm of dosing. Physiological limits restrict the application of WBH which has moved toward the mild temperature range, targeting immune support. LRHT does not have a temperature limit in the tumor (which can be burned out in extreme conditions) but a trend has started toward milder temperatures with immune-oriented goals, developing toward immune modulation, and especially toward tumor-specific immune reactions by which LRHT seeks to target the malignancy systemically. The emerging research of bystander and abscopal effects, in both laboratory investigations and clinical applications, has been intensified. Our present review summarizes the methods and results, and discusses the trends of hyperthermia in oncology.

Modulated Electro-Hyperthermia-Induced Tumor Damage Mechanisms Revealed in Cancer Models

The benefits of high-fever range hyperthermia have been utilized in medicine from the Ancient Greek culture to the present day. Amplitude-modulated electro-hyperthermia, induced by a 13.56 MHz radiofrequency current (mEHT, or Oncothermia), has been an emerging means of delivering loco-regional clinical hyperthermia as a complementary of radiation-, chemo-, and molecular targeted oncotherapy. This unique treatment exploits the metabolic shift in cancer, resulting in elevated oxidative glycolysis (Warburg effect), ion concentration, and electric conductivity. These promote the enrichment of electric fields and induce heat (controlled at 42 °C), as well as ion fluxes and disequilibrium through tumor cell membrane channels. By now, accumulating preclinical studies using in vitro and in vivo models of different cancer types have revealed details of the mechanism and molecular background of the oncoreductive effects of mEHT monotherapy. These include the induction of DNA double-strand breaks, irreversible heath and cell stress, and programmed cells death; the upregulation of molecular chaperones and damage (DAMP) signaling, which may contribute to a secondary immunogenic tumor cell death. In combination therapies, mEHT proved to be a good chemosensitizer through increasing drug uptake and tumor reductive effects, as well as a good radiosensitizer by downregulating hypoxia-related target genes. Recently, immune stimulation or intratumoral antigen-presenting dendritic cell injection have been able to extend the impact of local mEHT into a systemic "abscopal" effect. The complex network of pathways emerging from the published mEHT experiments has not been overviewed and arranged yet into a framework to reveal links between the pieces of the "puzzle". In this paper, we review the mEHT-related damage mechanisms published in tumor models, which may allow some geno-/phenotype treatment efficiency correlations to be exploited both in further research and for more rational clinical treatment planning when mEHT is involved in combination therapies.

Potential enhancement of host immunity and anti-tumor efficacy of nanoscale curcumin and resveratrol in colorectal cancers by modulated electro- hyperthermia

BACKGROUND

Modulated electro-hyperthermia (mEHT) is a form of hyperthermia used in cancer treatment. mEHT has demonstrated the ability to activate host immunity by inducing the release of heat shock proteins, triggering apoptosis, and destroying the integrity of cell membranes to enhance cellular uptake of chemo-drugs in tumor cells. Both curcumin and resveratrol are phytochemicals that function as effective antioxidants, immune activators, and potential inhibitors of tumor development. However, poor bioavailability is a major obstacle for use in clinical cancer treatment.

METHODS

This purpose of this study was to investigate whether mEHT can increase anti-cancer efficacy of nanosized curcumin and resveratrol in in vitro and in vivo models. The in vitro study included cell proliferation assay, cell cycle, and apoptosis analysis. Serum concentration was analyzed for the absorption of curcumin and resveratrol in SD rat model. The in vivo CT26/BALB/c animal tumor model was used for validating the safety, tumor growth curve, and immune cell infiltration within tumor tissues after combined mEHT/curcumin/resveratrol treatment.

RESULTS

The results indicate co-treatment of mEHT with nano-curcumin and resveratrol significantly induced cell cycle arrest and apoptosis of CT26 cells. The serum concentrations of curcumin and resveratrol were significantly elevated when mEHT was applied. The combination also inhibited the growth of CT26 colon cancer by inducing apoptosis and HSP70 expression of tumor cells while recruiting CD3+ T-cells and F4/80+ macrophages.

CONCLUSIONS

The results of this study have suggested that this natural, non-toxic compound can be an effective anti-tumor strategy for clinical cancer therapy. mEHT can enable cellular uptake of potential anti-tumor materials and create a favorable tumor microenvironment for an immunological chain reaction that improves the success of combined treatments of curcumin and resveratrol.

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.

Therapeutic Nanoparticles and Their Targeted Delivery Applications

Nanotechnology offers many advantages in various fields of science. In this regard, nanoparticles are the essential building blocks of nanotechnology. Recent advances in nanotechnology have proven that nanoparticles acquire a great potential in medical applications. Formation of stable interactions with ligands, variability in size and shape, high carrier capacity, and convenience of binding of both hydrophilic and hydrophobic substances make nanoparticles favorable platforms for the target-specific and controlled delivery of micro- and macromolecules in disease therapy. Nanoparticles combined with the therapeutic agents overcome problems associated with conventional therapy; however, some issues like side effects and toxicity are still debated and should be well concerned before their utilization in biological systems. It is therefore important to understand the specific properties of therapeutic nanoparticles and their delivery strategies. Here, we provide an overview on the unique features of nanoparticles in the biological systems. We emphasize on the type of clinically used nanoparticles and their specificity for therapeutic applications, as well as on their current delivery strategies for specific diseases such as cancer, infectious, autoimmune, cardiovascular, neurodegenerative, ocular, and pulmonary diseases. Understanding of the characteristics of nanoparticles and their interactions with the biological environment will enable us to establish novel strategies for the treatment, prevention, and diagnosis in many diseases, particularly untreatable ones.

Differences of the Immune Phenotype of Breast Cancer Cells after Ex Vivo Hyperthermia by Warm-Water or Microwave Radiation in a Closed-Loop System Alone or in Combination with Radiotherapy

The treatment of breast cancer by radiotherapy can be complemented by hyperthermia. Little is known about how the immune phenotype of tumor cells is changed thereby, also in terms of a dependence on the heating method. We developed a sterile closed-loop system, using either a warm-water bath or a microwave at 2.45 GHz to examine the impact of ex vivo hyperthermia on cell death, the release of HSP70, and the expression of immune checkpoint molecules (ICMs) on MCF-7 and MDA-MB-231 breast cancer cells by multicolor flow cytometry and ELISA. Heating was performed between 39 and 44 °C. Numerical process simulations identified temperature distributions. Additionally, irradiation with 2 × 5 Gy or 5 × 2 Gy was applied. We observed a release of HSP70 after hyperthermia at all examined temperatures and independently of the heating method, but microwave heating was more effective in cell killing, and microwave heating with and without radiotherapy increased subsequent HSP70 concentrations. Adding hyperthermia to radiotherapy, dynamically or individually, affected the expression of the ICM PD-L1, PD-L2, HVEM, ICOS-L, CD137-L, OX40-L, CD27-L, and EGFR on breast cancer cells. Well-characterized pre-clinical heating systems are mandatory to screen the immune phenotype of tumor cells in clinically relevant settings to define immune matrices for therapy adaption.

Smart microgels as drug delivery vehicles for the natural drug aescin: uptake, release and interactions

In the present study, we show how acrylamide-based microgels can be employed for the uptake and release of the drug β-aescin, a widely used natural product with a variety of pharmacological effects. We show how aescin is incorporated into the microgel particles. It has an important influence on the structure of the microgels, by reducing their natural network-density gradient in the swollen state. Moreover, temperature-dependent measurements reveal how the incorporation of aescin stabilizes the microgel particles, while the volume phase transition temperature (VPTT) is almost constant, which is very important for the intended drug release. Finally, it is shown that upon increase of the temperature above the VPTT the particles are able to release aescin from their network, encouraging the use of this particular drug delivery system for hypothermia treatments.

A randomized phase II trial of best supportive care with or without hyperthermia and vitamin C for heavily pretreated, advanced, refractory non-small-cell lung cancer

Our previous study indicated that intravenous vitamin C (IVC) treatment concurrent with modulated electrohyperthermia (mEHT) was safe and improved the quality of life (QoL) of non-small-cell lung cancer (NSCLC) patients. The aim of this trial was to further verify the efficacy of the above combination therapy in previously treated patients with refractory advanced (stage IIIb or IV) NSCLC. A total of 97 patients were randomized to receive IVC and mEHT plus best supportive care (BSC) (n = 49 in the active arm, receiving 1 g/kg * d IVC concurrently with mEHT, three times a week for 25 treatments in total) or BSC alone (n = 48 in the control arm). After a median follow-up of 24 months, progression-free survival (PFS) and overall survival (OS) were significantly prolonged by combination therapy compared to BSC alone (PFS: 3 months vs 1.85 months, P < 0.05; OS: 9.4 months vs 5.6 months, P < 0.05). QoL was significantly increased in the active arm despite the advanced stage of disease. The 3-month disease control rate after treatment was 42.9% in the active arm and 16.7% in the control arm (P < 0.05). Overall, IVC and mEHT may have the ability to improve the prognosis of patients with advanced NSCLC.

The effect of modulated electro-hyperthermia on local disease control in HIV-positive and -negative cervical cancer women in South Africa: Early results from a phase III randomised controlled trial

Background

The global burden of cervical cancer remains high with the highest morbidity and mortality rates reported in developing countries. Hyperthermia as a chemo- and radiosensitiser has shown to improve treatment outcomes. This is an analysis of the local control results at six months post-treatment of patients enrolled in an ongoing study investigating the effects of the addition of modulated electro-hyperthermia (mEHT) to chemoradiotherapy for the treatment of HIV-positive and -negative cervical cancer patients in a low-resource setting.

Methods

This ongoing Phase III randomised controlled trial, conducted at a state hospital in Johannesburg, South Africa, was registered with the appropriate ethics committee. After signing an informed consent, participants with FIGO stages IIB to IIIB squamous cell carcinoma of the cervix were randomised to receive chemoradiotherapy with/without mEHT using a secure online random-sampling tool (stratum: HIV status) accounting for age and stage. Reporting physicians were blind to treatment allocation. HIV-positive participants on antiretroviral treatment, or with a CD4 count >200cell/μL were included. mEHT was administered 2/weekly immediately before external beam radiation. The primary end point is local disease control (LDC) and secondary endpoints are toxicity; quality of life analysis; and two year survival. We report on six month LDC, including nodes visualised in the radiation field on ¹⁸F-FDG PET/CT (censored for six month survival), and six month local disease free survival (LDFS) (based on intention to treat). Trial status: Recruitment closed (ClinicalTrials.gov: NCT03332069).

Results

271 participants were recruited between January 2014 and November 2017, of which 210 were randomised for trial and 202 were available for analysis at six months post-treatment (mEHT: n = 101; Control: n = 101). Six month LDFS was higher in the mEHT Group (n = 39[38.6%]), than in the Control Group (n = 20[19.8%]); p = 0.003). LDC was also higher in the mEHT Group (n = 40[45.5%]) than the Control Group (n = 20[24.1%]); (p = 0.003).

Conclusion

Our results show that mEHT is effective as a chemo-radiosensitiser for cervical cancer, even in high risk a patients and resource-constrained settings.

Modulated electro-hyperthermia induced p53 driven apoptosis and cell cycle arrest additively support doxorubicin chemotherapy of colorectal cancer in vitro

OBJECTIVE

Modulated electro-hyperthermia (mEHT), a noninvasive complementary treatment of human chemo- and radiotherapy, can generate selective ~42°C heat in cancer due to elevated glycolysis (Warburg-effect) and electric conductivity in malignant tissues. Here we tested the molecular background of mEHT and its combination with doxorubicin chemotherapy using an in vitro model.

METHODS

C26 mouse colorectal adenocarcinoma cultures were mEHT treated at 42°C for 2 × 60 minutes (with 120 minutes interruption) either alone or in combination with 1 µmol/L doxorubicin (mEHT + Dox). Cell stress response, apoptosis, and cell cycle regulation related markers were detected using qPCR and immunocytochemistry supported with resazurin cell viability assay, cell death analysis using flow-cytometry and clonogenic assay.

RESULT

Cell-stress by mEHT alone was indicated by the significant upregulation and release of hsp70 and calreticulin proteins 3 hours posttreatment. Between 3 and 9 hours after treatment significantly reduced anti-apoptotic XIAP, BCL-2, and BCL-XL and elevated pro-apoptotic BAX and PUMA, as well as the cyclin dependent kinase inhibitor p21^waf1 mRNA levels were detected. After 24 hours, major elevation and nuclear translocation of phospho-p53(Ser15) protein levels and reduced phospho-Akt(Ser473) levels were accompanied by a significant caspase-3-mediated programmed cell death response. While mEHT dominantly induced apoptosis, Dox administration primarily led to tumor cell necrosis, and both significantly reduced the number of tumor progenitor colonies 10 days post-treatment. Furthermore, mEHT promoted the uptake of Dox by tumor cells and the combined treatment additively reduced tumor cell viability and augmented cell death near to synergy.

CONCLUSION

In C26 colorectal adenocarcinoma mEHT-induced irreversible cell stress can activate both caspase-dependent apoptosis and p21^waf1 mediated growth arrest pathways, likely to be driven by the upregulated nuclear p53 protein. Elevated phospho-p53(Ser15) might contribute to p53 escape from mdm2 control, which was further supported by reduced phospho-Akt(Ser473) protein levels. In combinations, mEHT could promote the uptake and significantly potentiate the cytotoxic effect of doxorubicin.

Boosting Abscopal Response to Radiotherapy with Sargramostim: A Review of Data and Ongoing Studies

Drug development in oncology today routinely focuses on approaches that utilize the patients’ immune system to destroy the malignancy. Combinatorial approaches of antineoplastic agents, both new and old, are being incorporated in the armamentarium of cancer treatments. The overarching goal of therapy remains the achievement of a complete and durable response with long term remission or cure. One approach in advancing treatment is aimed at strategies that improve immunological memory to induce long lasting immunity against the tumor. Although radiation therapy has not traditionally been thought to elicit an immunological effect, an increasing number of reports document the induction of an immune response against a tumor that kills cancer cells distant to the original site of treatment after local irradiation to a tumor. This phenomenon is called an abscopal effect. Since radiation alone is rarely associated with such a response, it is being combined with immuno-oncology drugs in an attempt to enhance response. One such strategy combines sargramostim, a recombinant human granulocyte macrophage colony stimulating factor (rhu GM-CSF), with radiotherapy. GM-CSF is a cytokine secreted by multiple cells types that promotes maturation of dendritic cells and enables the presentation of tumor-associated antigens to generate a T-cell response. This review article discusses the outcomes of clinical trials and case reports examining the efficacy and safety of combining radiation therapy with this immunomodulatory agent. We will also examine future studies and challenges facing the translation of this therapeutic approach.

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

Purpose

Modulated 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 methods

Water 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.

Results

mEHT 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.

Conclusion

The 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.

Oncological hyperthermia: The correct dosing in clinical applications

The problem with the application of conventional hyperthermia in oncology is firmly connected to the dose definition, which conventionally uses the concept of the homogeneous (isothermal) temperature of the target. Its imprecise control and complex evaluation is the primary barrier to the extensive clinical applications. The aim of this study was to show the basis of the problems of the misleading dose concept. A clear clarification of the proper dose concept must begin with the description of the limitations of the present doses in conventional hyperthermia applications. The surmounting of the limits the dose of oncologic hyperthermia has to be based on the applicability of the Eyring transition state theory on thermal effects. In order to avoid the countereffects of thermal homeostasis, the use of precise heating on the nanoscale with highly efficient energy delivery is recommended. The nano‑scale heating allows for an energy‑based dose to control the process. The main aspects of the method are the following: i) It is not isothermal (no homogeneous heating); ii) malignant cells are heated selectively; and iii) it employs high heating efficacy, with less energy loss. The applied rigorous thermodynamical considerations show the proper terminology and dose concept of hyperthermia, which is based on the energy‑absorption (such as in the case of ionizing radiation) instead of the temperature‑based ideas. On the whole, according to the present study, the appropriate dose in oncological hyperthermia must use an energy‑based concept, as it is well‑known in all the ionizing radiation therapies. We propose the use of Gy (J/kg) in cases of non‑ionizing radiation (hyperthermia) as well.

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.

Modulated Electrohyperthermia in Integrative Cancer Treatment for Relapsed Malignant Glioblastoma and Astrocytoma: Retrospective Multicenter Controlled Study

BACKGROUND

There are interesting studies on glioma therapy with modulated electrohyperthermia (mEHT), which combines heat therapy with an electric field. Clinical researchers not only found the mEHT method feasible for palliation but also reported evidence of therapeutic response.

PURPOSE

To study the efficacy and safety of mEHT for the treatment of relapsed malignant glioma and astrocytoma versus best supportive care (BSC).

METHODS

We collected data retrospectively on 149 patients affected by malignant glioma and astrocytoma. Inclusion criteria were informed consent signed; >18 years old; histological diagnosis of malignant glioma or astrocytoma; relapsed after surgery, adjuvant temozolomide-based chemotherapy, and radiotherapy; and indication for treatment with mEHT in palliative setting. mEHT was performed with capacitive coupling technique keeping the skin surface at 26°C and the tumor temperature at 40°C to 42.5°C for > 90% of treatment duration (20-60 minutes). The applied power was 40 to 150 W using a step-up heating protocol. Results from patients treated with mEHT were compared with those treated with BSC.

RESULTS

A total of 149 consecutive patients were enrolled in the study, 111 (74%) had glioblastoma multiforme (GBM), and 38 (26%) had astrocytoma (AST). mEHT was performed for 28 (25%) of GBM and 24 (63%) of AST patients. Tumor response at the 3-month follow-up was observed in 29% and 48% of GBM and AST patients after mEHT, and in 4% and 10% of GBM and AST patients after BSC, respectively. The survival rate at first and second year in the mEHT group was 77.3% and 40.9% for AST, and 61% and 29% for GBM, respectively. The 5-year overall survival of AST was 83% after mEHT versus 25% after BSC and 3.5% after mEHT versus 1.2% after BSC for GBM. The median overall survival of mEHT was 14 months (range 2-108 months) for GBM and 16.5 months (range 3-156 months) for the AST group. We observed 4 long-term survivors in the AST and 2 in the GBM group. Two of the long survivors in AST and 1 in GBM group were treated by mEHT.

CONCLUSIONS

mEHT in integrative therapy may have a promising role in the treatment and palliation of relapsed GBM and AST.

In vitro comparison of conventional hyperthermia and modulated electro-hyperthermia

Radiofrequency-induced hyperthermia (HT) treatments for cancer include conventional capacitive coupling hyperthermia (cCHT) and modulated electro-hyperthermia (mEHT). In this study, we directly compared these methods with regard to in vitro cytotoxicity and mechanisms of action under isothermal conditions. Hepatoma (HepG2) cells were exposed to HT treatment (42°C for 30 min) using mEHT, cCHT or a water bath. mEHT produced a much higher apoptosis rate (43.1% ± 5.8%) than cCHT (10.0% ± 0.6%), the water bath (8.4% ± 1.7%) or a 37°C control (6.6% ± 1.1%). The apoptosis-inducing effect of mEHT at 42°C was similar to that achieved with a water bath at 46°C. mEHT also increased expression of caspase-3, 8 and 9. All three hyperthermia methods increased intracellular heat shock protein 70 (Hsp70) levels, but only mEHT greatly increased the release of Hsp70 from cells. Calreticulin and E-cadherin levels in the cell membrane also increased after mEHT treatment, but not after cCHT or water bath. These results suggest that mEHT selectively deposits energy on the cell membrane and may be a useful treatment modality that targets cancer cell membranes.

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.

Clinical and economic evaluation of modulated electrohyperthermia concurrent to dose-dense temozolomide 21/28 days regimen in the treatment of recurrent glioblastoma: a retrospective analysis of a two-centre German cohort trial with systematic comparison and effect-to-treatment analysis

OBJECTIVE

To assess the efficacy and cost-effectiveness of modulated electrohyperthermia (mEHT) concurrent to dose-dense temozolomide (ddTMZ) 21/28 days regimen versus ddTMZ 21/28 days alone in patients with recurrent glioblastoma (GBM).

DESIGN

A cohort of 54 patients with recurrent GBM treated with ddTMZ+mEHT in 2000-2005 was systematically retrospectively compared with five pooled ddTMZ 21/28 days cohorts (114 patients) enrolled in 2008-2013.

RESULTS

The ddTMZ+mEHT cohort had a not significantly improved mean survival time (mST) versus the comparator (p=0.531) after a significantly less mean number of cycles (1.56 vs 3.98, p<0.001). Effect-to-treatment analysis (ETA) suggests that mEHT significantly enhances the efficacy of the ddTMZ 21/28 days regimen (p=0.011), with significantly less toxicity (no grade III-IV toxicity vs 45%-92%, p<0.0001). An estimated maximal attainable median survival time is 10.10 months (9.10-11.10). Cost-effectiveness analysis suggests that, unlike ddTMZ 21/28 days alone, ddTMZ+mEHT is cost-effective versus the applicable cost-effectiveness thresholds €US$25 000-50 000/quality-adjusted life year (QALY). Budget impact analysis suggests a significant saving of €8 577 947/$11 201 761 with 29.1-38.5 QALY gained per 1000 patients per year. Cost-benefit analysis suggests that mEHT is profitable and will generate revenues between €3 124 574 and $6 458 400, with a total economic effect (saving+revenues) of €5 700 034 to $8 237 432 per mEHT device over an 8-year period.

CONCLUSIONS

Our ETA suggests that mEHT significantly improves survival of patients receiving the ddTMZ 21/28 days regimen. Economic evaluation suggests that ddTMZ+mEHT is cost-effective, budget-saving and profitable. After confirmation of the results, mEHT could be recommended for the treatment of recurrent GBM as a cost-effective enhancer of ddTMZ regimens, and, probably, of the regular 5/28 days regimen. mEHT is applicable also as a single treatment if chemotherapy is impossible, and as a salvage treatment after the failure of chemotherapy.

The safety and pharmacokinetics of high dose intravenous ascorbic acid synergy with modulated electrohyperthermia in Chinese patients with stage III-IV non-small cell lung cancer

Ascorbic acid (AA) infusion and modulated electrohyperthermia (mEHT) are widely used by integrative cancer practitioners for many years. However, there are no safety and pharmacokinetics data in Chinese cancer patients. We carried out a clinical trial to evaluate the safety and pharmacokinetics of those methods in patients with stage III-IV non-small cell lung cancer (NSCLC). Blood ascorbic acid in the fasting state was obtained from 35 NSCLC patients; selecting from them 15 patients with stage III-IV entered the phase I study. They were randomized allocated into 3 groups, and received doses 1.0, 1.2, 1.5g/kg AA infusions. Participants in the first group received intravenous AA (IVAA) when mEHT was finished, in the second group IVAA was administered simultaneously with mEHT and in the third group IVAA was applied first, and followed with mEHT. Pharmacokinetic profiles were obtained when they received solely IVAA and when IVAA in combination with mEHT. The process was applied 3 times a week (every other day, weekend days off) for 4weeks. We found that fasting plasma AA levels were significantly correlated with stage of the disease. Peak concentration of AA was significantly higher in the simultaneous treatments than in other combinations with mEHT or in solely IVAA-managed groups. IVAA synergy with simultaneous mEHT is safe and the concomitant application significantly increases the plasma AA level for NSCLC patients.

Local modulated electro-hyperthermia in combination with traditional Chinese medicine vs. intraperitoneal chemoinfusion for the treatment of peritoneal carcinomatosis with malignant ascites: A phase II randomized trial

The purpose of this study was to develop a safe and non-toxic alternative to the conventional conservative treatment of peritoneal carcinomatosis with malignant ascites (PCMA) by investigating the efficacy and safety of local modulated electro-hyperthermia (mEHT) combined with the traditional Chinese medicine (TCM) 'Shi Pi' herbal decoction, compared with standard intraperitoneal chemoinfusion (IPCI). A randomized, controlled, single-center, open-label clinical trial (phase II) with two parallel groups (allocation ratio, 1:1) was conducted to investigate the efficacy and safety of mEHT+TCM (study group, SG) vs. standard IPCI (control group, CG) in patients with PCMA by intention-to-treat analysis. A total of 260 patients with PCMA were randomly allocated into the two groups (130/130); mEHT was applied for 60 min per session every second day for 4 weeks, for a total of 14 sessions. The TCM decoction was administered orally, at 400 ml daily. In CG, occlusive IPCI with cisplatin (30-60 mg) and fluorouracil (500-600 mg/m²) was applied twice, biweekly. The objective response rate (ORR), quality of life (QoL) and adverse event rate (AER) in the two groups were evaluated 1 month after treatment, analyzed and compared. The present study is registered on ClinicalTrials.gov (NCT02638051). No case was lost or excluded (0/260). The ORR in SG was 77.69% (101/130) vs. 63.85% (73/130) in CG (P<0.05). The QoL in SG was 49.23% vs. 32.3% in CG (P<0.05). The AER in SG was 2.3% (3/130) vs. 12.3% (16/130) in CG (P<0.05). All the adverse events were grade I. In conclusion, the combination of mEHT with TCM achieves better control of PCMA compared with standard IPCI, with less toxicity. Both components of the combination are non-toxic treatments easily tolerated by patients. Thus, this combined treatment may be preferred due to the better benefit-harm balance.

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.

Improving immunological tumor microenvironment using electro-hyperthermia followed by dendritic cell immunotherapy

Background

The treatment of intratumoral dentritic cells (DCs) commonly fails because it cannot evoke immunity in a poor tumor microenvironment (TME). Modulated electro-hyperthermia (mEHT, trade-name: oncothermia) represents a significant technological advancement in the hyperthermia field, allowing the autofocusing of electromagnetic power on a cell membrane to generate massive apoptosis. This approach turns local immunogenic cancer cell death (apoptosis) into a systemic anti-tumor immune response and may be implemented by treatment with intratumoral DCs.

Methods

The CT26 murine colorectal cancer model was used in this investigation. The inhibition of growth of the tumor and the systemic anti-tumor immune response were measured. The tumor was heated to a core temperature of 42 °C for 30 min. The matured synergetic DCs were intratumorally injected 24 h following mEHT was applied.

Results

mEHT induced significant apoptosis and enhanced the release of heat shock protein70 (Hsp70) in CT26 tumors. Treatment with mEHT-DCs significantly inhibited CT26 tumor growth, relative to DCs alone or mEHT alone. The secondary tumor protection effect upon rechallenging was observed in mice that were treated with mEHT-DCs. Immunohistochemical staining of CD45 and F4/80 revealed that mEHT-DC treatment increased the number of leukocytes and macrophages. Most interestingly, mEHT also induced infiltrations of eosinophil, which has recently been reported to be an orchestrator of a specific T cell response. Cytotoxic T cell assay and ELISpot assay revealed a tumor-specific T cell activity.

Conclusions

This study demonstrated that mEHT induces tumor cell apoptosis and enhances the release of Hsp70 from heated tumor cells, unlike conventional hyperthermia. mEHT can create a favorable tumor microenvironment for an immunological chain reaction that improves the success rate of intratumoral DC immunotherapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1690-2) contains supplementary material, which is available to authorized users.

Electro-hyperthermia inhibits glioma tumorigenicity through the induction of E2F1-mediated apoptosis

PURPOSE

Modulated electro-hyperthermia (mEHT), also known as oncothermia, shows remarkable treatment efficacies for various types of tumours, including glioma. The aim of the present study was to investigate the molecular mechanism underlying phenotypic changes in oncothermic cancer cells.

MATERIALS AND METHODS

U87-MG and A172 human glioma cells were exposed to mEHT (42 °C/60 min) three times with a 2-day interval and subsequently tested for growth inhibition using MTS, FACS and microscopic analysis. To obtain insights into the molecular changes in response to mEHT, global changes in gene expression were examined using RNA sequencing. For in vivo evaluation of mEHT, we used U87-MG glioma xenografts grown in nude mice.

RESULTS

mEHT inhibited glioma cell growth through the strong induction of apoptosis. The transcriptomic analysis of differential gene expression under mEHT showed that the anti-proliferative effects were induced through a subset of molecular alterations, including the up-regulation of E2F1 and CPSF2 and the down-regulation of ADAR and PSAT1. Subsequent Western blotting revealed that mEHT increased the levels of E2F1 and p53 and decreased the level of PARP-1, accelerating apoptotic signalling in glioma cells. mEHT significantly suppressed the growth of human glioma xenografts in nude mice. We also observed that mEHT dramatically reduced the portion of CD133(+) glioma stem cell population and suppressed cancer cell migration and sphere formation.

CONCLUSIONS

These findings suggest that mEHT suppresses glioma cell proliferation and mobility through the induction of E2F1-mediated apoptosis and might be an effective treatment for eradicating brain tumours.

Upregulation of heat shock proteins and the promotion of damage-associated molecular pattern signals in a colorectal cancer model by modulated electrohyperthermia

In modulated electrohyperthermia (mEHT) the enrichment of electric field and the concomitant heat can selectively induce cell death in malignant tumors as a result of elevated glycolysis, lactate production (Warburg effect), and reduced electric impedance in cancer compared to normal tissues. Earlier, we showed in HT29 colorectal cancer xenografts that the mEHT-provoked programmed cell death was dominantly caspase independent and driven by apoptosis inducing factor activation. Using this model here, we studied the mEHT-related cell stress 0-, 1-, 4-, 8-, 14-, 24-, 48-, 72-, 120-, 168- and 216-h post-treatment by focusing on damage-associated molecular pattern (DAMP) signals. Significant cell death response upon mEHT treatment was accompanied by the early upregulation (4-h post-treatment) of heat shock protein (Hsp70 and Hsp90) mRNA levels. In situ, the treatment resulted in spatiotemporal occurrence of a DAMP protein signal sequence featured by the significant cytoplasmic to cell membrane translocation of calreticulin at 4 h, Hsp70 between 14 and 24 h and Hsp90 between 24- and 216-h post-treatment. The release of high-mobility group box1 protein (HMGB1) from tumor cell nuclei from 24-h post-treatment and its clearance from tumor cells by 48 h was also detected. Our results suggest that mEHT treatment can induce a DAMP-related signal sequence in colorectal cancer xenografts that may be relevant for promoting immunological cell death response, which need to be further tested in immune-competent animals.

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.

The effects of non-invasive radiofrequency treatment and hyperthermia on malignant and nonmalignant cells

Background: Exposure of biological subjects to electromagnetic fields with a high frequency is associated with temperature elevation. In our recent studies, we reported that non-invasive radiofrequency (RF) treatment at 13.56 MHz with the field ranging from 1 KeV to 20 KeV/m² inhibits tumor progression in animals with abdominal tumor xenografts and enhances the anticancer effect of chemotherapy. The RF treatment was followed by temperature elevation in tumors to approximately 46 °C during 10 min of exposure. In contrast, the temperature of normal tissues remained within a normal range at approximately 37 °C. Whether all biological effects of RF treatment are limited to its hyperthermic property remains unclear. Here, we compared how RF and hyperthermia (HT) treatments change the proliferation rate, oxygen consumption and autophagy in malignant and nonmalignant cells. Methods: In the current study, cancer and nonmalignant cells of pancreatic origin were exposed to the RF field or to conventional HT at 46 °C, which was chosen based on our previous in vivo studies of the tumor-specific RF-induced hyperthermia. Results: Only RF treatment caused declines in cancer cell viability and proliferation. RF treatment also affected mitochondrial function in cancer cells more than HT treatment did and, unlike HT treatment, was followed by the elevation of autophagosomes in the cytoplasm of cancer cells. Importantly, the effects of RF treatment were negligible in nonmalignant cells. Conclusion: The obtained data indicate that the effects of RF treatment are specific to cancer cells and are not limited to its hyperthermic property.

Current status of oncothermia therapy for lung cancer

Lung cancer is one of the most common malignant tumors, and it has the highest death rate. Oncothermia is a feasible and successful treatment for lung cancer. Results show a remarkable survival benefit for patients, with a good quality of life. The treatment has no, or in some cases mild, side-effects and could decrease the adverse effects of the complementary treatment. Applying oncothermia together with other treatment methods could increase the effects and result in better performance. A comparison of studies demonstrates a good correspondence in the data, which strengthens the reliability of the studies, and clearly shows the feasibility of the application of oncothermia to treating all kinds of pulmonary malignancies including non-small-cell and small-cell primary tumors, and all of the metastatic diseases of the pulmonary system.

Early Changes in mRNA and Protein Expression Related to Cancer Treatment by Modulated Electrohyperthermia

Modulated electrohyperthermia (mEHT), generated by capacitive coupled, modulated 13.56 MHz radiofrequency, is a noninvasive technique for targeted tumor treatment based on elevated ion concentration and electric admittance in malignant tumors. In this study, we tested early changes in protein expression related to tumor destruction upon a single shot of 30-minute mEHT treatment of xenografted human colorectal cell line (HT29) implanted into the femoral region of Balb/c nu/nu mice. Treatment-related mRNA expression profiling was done using the human genome U133 Plus 2.0 Arrays. Apoptosis protein arrays and immunohistochemistry were performed for validating changes at the protein level. The mEHT treatment resulted in major expression changes in 48 genes including several heat-shock proteins. Apoptosis protein arrays revealed the upregulation of death receptors, Bcl-2 superfamily mitochondrial apoptosis regulatory proteins, and heat-shock proteins, which were also confirmed in situ. Within 24-hour post-treatment, mEHT resulted in the upregulation apoptosis induction and heat-shock-related gene and protein expression in HT29 colorectal cancer xenografts contributing to tumor destruction.

Hyperthermia versus Oncothermia: Cellular Effects in Cancer Therapy

Hyperthermia means overheating of the living object completely or partly. Hyperthermia, the procedure of raising the temperature of a part of or the whole body above the normal for a defined period of time, is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. The fact that is the hyperthermia is not generally accepted as conventional therapy. The problem is its controversial performance. The controversy is originated from the complications of the deep heating and the focusing of the heat effect. The idea of oncothermia solves the selective deep action on nearly cellular resolution. We would like to demonstrate the force and perspectives of oncothermia as a highly specialized hyperthermia in clinical oncology. Our aim is to prove the ability of oncothermia to be a candidate to become a widely accepted modality of the standard cancer care. We would like to show the proofs and the challenges of the hyperthermia and oncothermia applications to provide the presently available data and summarize the knowledge in the topic. Like many early-stage therapies, oncothermia lacks adequate treatment experience and long-range, comprehensive statistics that can help us optimize its use for all indications.

Hyperthermia versus Oncothermia: Cellular Effects in Complementary Cancer Therapy

Hyperthermia means overheating of the living object completely or partly. Hyperthermia, the procedure of raising the temperature of a part of or the whole body above normal for a defined period of time, is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. However, hyperthermia is not generally accepted as conventional therapy. The problem is its controversial performance. The controversy is originated from the complications of the deep heating and the focusing of the heat effect. The idea of oncothermia solves the selective deep action on nearly cellular resolution. We would like to demonstrate the force and perspectives of oncothermia, as a highly specialized hyperthermia in clinical oncology. Our aim is to prove the ability of oncothermia to be a candidate to become a widely accepted modality of the standard cancer care. We would like to show the proofs and the challenges of the hyperthermia and oncothermia applications to provide the presently available data and summarize the knowledge in the topic. Like many early stage therapies, oncothermia lacks adequate treatment experience and long-range, comprehensive statistics that can help us optimize its use for all indications.