Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Front Microbiol ; 14: 1296558, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094629

RESUMO

Coronaviruses are the causative agents of several recent outbreaks, including the COVID-19 pandemic. One therapeutic approach is blocking viral binding to the host receptor. As binding largely depends on electrostatic interactions, we hypothesized possible inhibition of viral infection through application of electric fields, and tested the effectiveness of Tumor Treating Fields (TTFields), a clinically approved cancer treatment based on delivery of electric fields. In preclinical models, TTFields were found to inhibit coronavirus infection and replication, leading to lower viral secretion and higher cell survival, and to formation of progeny virions with lower infectivity, overall demonstrating antiviral activity. In a pilot clinical study (NCT04953234), TTFields therapy was safe for patients with severe COVID-19, also demonstrating preliminary effectiveness data, that correlated with higher device usage.

2.
J Neurooncol ; 163(1): 83-94, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37131108

RESUMO

PURPOSE: Tumor Treating Fields (TTFields) are electric fields that disrupt cellular processes critical for cancer cell viability and tumor progression, ultimately leading to cell death. TTFields therapy is approved for treatment of newly-diagnosed glioblastoma (GBM) concurrent with maintenance temozolomide (TMZ). Recently, the benefit of TMZ in combination with lomustine (CCNU) was demonstrated in patients with O6-methylguanine DNA methyltransferase (MGMT) promoter methylation. The addition of adjuvant TTFields to TMZ plus CCNU further improved patient outcomes, leading to a CE mark for this regimen. The current in vitro study aimed to elucidate the mechanism underlying the benefit of this treatment protocol. METHODS: Human GBM cell lines with different MGMT promoter methylation statuses were treated with TTFields, TMZ, and CCNU, and effectiveness was tested by cell count, apoptosis, colony formation, and DNA damage measurements. Expression levels of relevant DNA-repair proteins were examined by western blot analysis. RESULTS: TTFields concomitant with TMZ displayed an additive effect, irrespective of MGMT expression levels. TTFields concomitant with CCNU or with CCNU plus TMZ was additive in MGMT-expressing cells and synergistic in MGMT-non-expressing cells. TTFields downregulated the FA-BRCA pathway and increased DNA damage induced by the chemotherapy combination. CONCLUSIONS: The results support the clinical benefit demonstrated for TTFields concomitant with TMZ plus CCNU. Since the FA-BRCA pathway is required for repair of DNA cross-links induced by CCNU in the absence of MGMT, the synergy demonstrated in MGMT promoter methylated cells when TTFields and CCNU were co-applied may be attributed to the BRCAness state induced by TTFields.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Lomustina/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Linhagem Celular , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral
4.
Int J Mol Sci ; 23(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36430552

RESUMO

Tumor Treating Fields (TTFields) are electric fields that exert physical forces to disrupt cellular processes critical for cancer cell viability and tumor progression. TTFields induce anti-mitotic effects through the disruption of the mitotic spindle and abnormal chromosome segregation, which trigger several forms of cell death, including immunogenic cell death (ICD). The efficacy of TTFields concomitant with anti-programmed death-1 (anti-PD-1) treatment was previously shown in vivo and is currently under clinical investigation. Here, the potential of TTFields concomitant with anti- PD-1/anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) or anti-programmed death-ligand 1 (anti-PD-L1) immune checkpoint inhibitors (ICI) to improve therapeutic efficacy was examined in lung tumor-bearing mice. Increased circulating levels of high mobility group box 1 protein (HMGB1) and elevated intratumoral levels of phosphorylated eukaryotic translation initiation factor 2α (p-eIF2α) were found in the TTFields-treated mice, indicative of ICD induction. The concomitant application of TTFields and ICI led to a significant decrease in tumor volume as compared to all other groups. In addition, significant increases in the number of tumor-infiltrating immune cells, specifically cytotoxic T-cells, were observed in the TTFields plus anti-PD-1/anti-CTLA-4 or anti-PD-L1 groups. Correspondingly, cytotoxic T-cells isolated from these tumors showed higher levels of IFN-γ production. Collectively, these results suggest that TTFields have an immunoactivating role that may be leveraged for concomitant treatment with ICI to achieve better tumor control by enhancing antitumor immunity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Camundongos , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Sobrevivência Celular/fisiologia , Fuso Acromático
5.
Cancers (Basel) ; 14(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35740624

RESUMO

Hepatocellular carcinoma (HCC), a highly aggressive liver cancer, is a leading cause of cancer-related death. Tumor Treating Fields (TTFields) are electric fields that exert antimitotic effects on cancerous cells. The aims of the current research were to test the efficacy of TTFields in HCC, explore the underlying mechanisms, and investigate the possible combination of TTFields with sorafenib, one of the few front-line treatments for patients with advanced HCC. HepG2 and Huh-7D12 human HCC cell lines were treated with TTFields at various frequencies to determine the optimal frequency eliciting maximal cell count reduction. Clonogenic, apoptotic effects, and autophagy induction were measured. The efficacy of TTFields alone and with concomitant sorafenib was tested in cell cultures and in an orthotopic N1S1 rat model. Tumor volume was examined at the beginning and following 5 days of treatment. At study cessation, tumors were weighed and examined by immunohistochemistry to assess autophagy and apoptosis. TTFields were found in vitro to exert maximal effect at 150 kHz, reducing cell count and colony formation, increasing apoptosis and autophagy, and augmenting the effects of sorafenib. In animals, TTFields concomitant with sorafenib reduced tumor weight and volume fold change, and increased cases of stable disease following treatment versus TTFields or sorafenib alone. While each treatment alone elevated levels of autophagy relative to control, TTFields concomitant with sorafenib induced a significant increase versus control in tumor ER stress and apoptosis levels, demonstrating increased stress under the multimodal treatment. Overall, TTFields treatment demonstrated efficacy and enhanced the effects of sorafenib for the treatment of HCC in vitro and in vivo, via a mechanism involving induction of autophagy.

6.
Lung Cancer ; 160: 99-110, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482104

RESUMO

OBJECTIVES: Tumor Treating Fields (TTFields) are low intensity, intermediate frequency, alternating electric fields with antimitotic effects on cancerous cells. TTFields concomitant with pemetrexed and a platinum agent are approved in the US and EU as first line therapy for unresectable, locally advanced or metastatic malignant pleural mesothelioma (MPM). The goal of the current study was to characterize the mechanism of action of TTFields in MPM cell lines and animal models. METHODS: Human MPM cell lines MSTO-211H and NCI-H2052 were treated with TTFields to determine the frequency that elicits maximal cytotoxicity. The effect of TTFields on DNA damage and repair, and the cytotoxic effect of TTFields in combination with cisplatin and/or pemetrexed were examined. Efficacy of TTFields concomitant with cisplatin and pemetrexed was evaluated in orthotopic IL-45 and subcutaneous RN5 murine models. RESULTS: TTFields at a frequency of 150 kHz demonstrated the highest cytotoxicity to MPM cells. Application of 150 kHz TTFields resulted in increased formation of DNA double strand breaks, elevated expression of DNA damage induced cell cycle arrest proteins, and reduced expression of Fanconi Anemia (FA)-BRCA DNA repair pathway proteins. Co-treatment of TTFields with cisplatin or pemetrexed significantly increased treatment efficacy versus each modality alone, with additivity and synergy exhibited by the TTFields-pemetrexed and TTFields-cisplatin combinations, respectively. In animal models, tumor volume was significantly lower for the TTFields-cisplatin-pemetrexed combination compared to control, accompanied by increased DNA damage within the tumor. CONCLUSION: This research demonstrated that the efficacy of TTFields for the treatment of MPM is associated with reduced expression of FA-BRCA pathway proteins and increased DNA damage. This mechanism of action is consistent with the observed synergism for TTFields-cisplatin vs additivity for TTFields-pemetrexed, as cisplatin-induced DNA damage is repaired via the FA-BRCA pathway.


Assuntos
Anemia de Fanconi , Neoplasias Pulmonares , Mesotelioma Maligno , Animais , Cisplatino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Pemetrexede
7.
Front Oncol ; 11: 670809, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249709

RESUMO

BACKGROUND: Tumor Treating Fields (TTFields) therapy is a non-invasive, loco-regional, anti-mitotic treatment modality that targets rapidly dividing cancerous cells, utilizing low intensity, alternating electric fields at cancer-cell-type specific frequencies. TTFields therapy is approved for the treatment of newly diagnosed and recurrent glioblastoma (GBM) in the US, Europe, Israel, Japan, and China. The favorable safety profile of TTFields in patients with GBM is partially attributed to the low rate of mitotic events in normal, quiescent brain cells. However, specific safety evaluations are warranted at locations with known high rates of cellular proliferation, such as the torso, which is a primary site of several of the most aggressive malignant tumors. METHODS: The safety of delivering TTFields to the torso of healthy rats at 150 or 200 kHz, which were previously identified as optimal frequencies for treating multiple torso cancers, was investigated. Throughout 2 weeks of TTFields application, animals underwent daily clinical examinations, and at treatment cessation blood samples and internal organs were examined. Computer simulations were performed to verify that the targeted internal organs of the torso were receiving TTFields at therapeutic intensities (≥ 1 V/cm root mean square, RMS). RESULTS: No treatment-related mortality was observed. Furthermore, no significant differences were observed between the TTFields-treated and control animals for all examined safety parameters: activity level, food and water intake, stools, motor neurological status, respiration, weight, complete blood count, blood biochemistry, and pathological findings of internal organs. TTFields intensities of 1 to 2.5 V/cm RMS were confirmed for internal organs within the target region. CONCLUSIONS: This research demonstrates the safety of therapeutic level TTFields at frequencies of 150 and 200 kHz when applied as monotherapy to the torso of healthy rats.

8.
Cancers (Basel) ; 12(10)2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33080774

RESUMO

Tumor Treating Fields (TTFields) are noninvasive, alternating electric fields within the intermediate frequency range (100-300 kHz) that are utilized as an antimitotic cancer treatment. TTFields are loco-regionally delivered to the tumor region through 2 pairs of transducer arrays placed on the skin. This novel treatment modality has been FDA-approved for use in patients with glioblastoma and malignant pleural mesothelioma based on clinical trial data demonstrating efficacy and safety; and is currently under investigation in other types of solid tumors. TTFields were shown to induce an anti-mitotic effect by exerting bi-directional forces on highly polar intracellular elements, such as tubulin and septin molecules, eliciting abnormal microtubule polymerization during spindle formation as well as aberrant cleavage furrow formation. Previous studies have demonstrated that TTFields inhibit metastatic properties in cancer cells. However, the consequences of TTFields application on cytoskeleton dynamics remain undetermined. In this study, methods utilized in combination to study the effects of TTFields on cancer cell motility through regulation of microtubule and actin dynamics included confocal microscopy, computational tools, and biochemical analyses. Mechanisms by which TTFields treatment disrupted cellular polarity were (1) interference with microtubule assembly and directionality; (2) altered regulation of Guanine nucleotide exchange factor-H1 (GEF-H1), Ras homolog family member A (RhoA), and Rho-associated coiled-coil kinase (ROCK) activity; and (3) induced formation of radial protrusions of peripheral actin filaments and focal adhesions. Overall, these data identified discrete effects of TTFields that disrupt processes crucial for cancer cell motility.

9.
Cancer Immunol Immunother ; 69(7): 1191-1204, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32144446

RESUMO

Tumor-treating fields (TTFields) are alternating electric fields in a specific frequency range (100-300 kHz) delivered to the human body through transducer arrays. In this study, we evaluated whether TTFields-mediated cell death can elicit antitumoral immunity and hence would be effectively combined with anti-PD-1 therapy. We demonstrate that in TTFields-treated cancer cells, damage-associated molecular patterns including high-mobility group B1 and adenosine triphosphate are released and calreticulin is exposed on the cell surface. Moreover, we show that TTFields treatment promotes the engulfment of cancer cells by dendritic cells (DCs) and DCs maturation in vitro, as well as recruitment of immune cells in vivo. Additionally, our study demonstrates that the combination of TTFields with anti-PD-1 therapy results in a significant decline of tumor volume and increase in the percentage of tumor-infiltrating leukocytes in two tumor models. In orthotopic lung tumors, these infiltrating leukocytes, specifically macrophages and DCs, showed elevated expression of PD-L1. Compatibly, cytotoxic T-cells isolated from these tumors demonstrated increased production of IFN-γ. In colon cancer tumors, T-cells infiltration was significantly increased following long treatment duration with TTFields plus anti-PD-1. Collectively, our results suggest that TTFields therapy can induce anticancer immune response. Furthermore, we demonstrate robust efficacy of concomitant application of TTFields and anti-PD-1 therapy. These data suggest that integrating TTFields with anti-PD-1 therapy may further enhance antitumor immunity, hence achieve better tumor control.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Carcinoma Hepatocelular/terapia , Carcinoma Pulmonar de Lewis/terapia , Terapia por Estimulação Elétrica/métodos , Morte Celular Imunogênica , Linfócitos do Interstício Tumoral/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Apoptose , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Proliferação de Células , Terapia Combinada , Feminino , Humanos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Clin Ultrasound ; 48(4): 204-210, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31867721

RESUMO

Transthoracic parametric Doppler (TPD), unlike conventional ultrasonography, measures signals originating from movements of pulmonary blood vessel walls. In this pilot study, we tested TPD in 15 patients diagnosed with pulmonary embolism on computed tomography pulmonary angiography. Results were mapped to the upper, middle, and lower thirds of the right lung. In the lower third, TPD yielded 100% specificity and positive predictive value for acute pulmonary embolism. If validated in a larger series, this rapid bedside technique might obviate the need for computed tomography in specific cases. This could be advantageous in patients who are unstable, in intensive care, or have allergies to iodinated contrast material.


Assuntos
Embolia Pulmonar/diagnóstico por imagem , Ultrassonografia Doppler , Doença Aguda , Adulto , Angiografia , Angiografia por Tomografia Computadorizada , Feminino , Hemodinâmica , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/fisiopatologia , Embolia Pulmonar/fisiopatologia , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/fisiopatologia , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
11.
J Clin Monit Comput ; 33(6): 1055-1060, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30661196

RESUMO

Lung Doppler signals (LDS) acquired via transthoracic echocardiography is a novel technology previously reported in adults for use in detecting pulmonary hypertension. The aim of this study was to characterize LDS in healthy children to establish normative pediatric LDS data, and compare the pediatric data to the previously published healthy adult LDS. In this prospective, two-center study, LDS were acquired in children without cardiopulmonary disease using a 2 MHz transthoracic pulsed Doppler transducer. The data were processed to obtain Doppler velocity patterns corresponding to phases of the cardiac cycle. Signals were analyzed using a parametric Doppler signal-processing package and performance evaluation of the trained classifiers was performed using cross validation method. Pediatric signals were then compared to a retrospective cohort of healthy adults. Eighty-six healthy pediatric subjects (mean age 9.1 ± 5.1 years) and 79 healthy adult controls (mean age 59.7 ± 10.7 years) were included. The normative LDS velocity profiles were defined for pediatric subjects and then compared to adults; the highest discriminating LDS parameters between healthy children and adults were acceleration of atrial (A) signal contraction (46 ± 18 vs. 90 ± 34; p < 0.001), peak systolic (S) signal velocity (10.0 ± 3.5 vs. 11.7 ± 3.5; p < 0.001), and ratio of peak diastolic (D)-to-atrial (A) signal velocity (1.4 ± 0.5 vs. 0.4 ± 0.3; p < 0.001). The sensitivity and specificity of this LDS based method to discern between healthy children and adult subjects was 98.6% and 97.4%, respectively. Subgroup analyses between younger (2-8 years) and older (9-18 years) pediatric LDS yielded significant differences between atrial (A) acceleration (43.7 ± 33.9 vs. 47.7 ± 42.1; p = 0.04) and diastolic (D)-to-atrial (A) signal velocity (1.2 ± 0.5 vs. 1.5 ± 0.5; p = 0.01) but not systolic (S) signals (0.14 ± 0.05 vs. 0.14 ± 0.05; p = 0.97). In this study, we defined the normal LDS profile for healthy children and have demonstrated differences in LDS between children and adults. Specifically, healthy children had lower atrial contraction power, differences in ventricular compliance and increased chronotropic response. Further studies are warranted to investigate the application of this technology, for example as a tool to aid in the detection of pulmonary hypertension in children.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Ecocardiografia , Pneumopatias/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Ultrassonografia Doppler , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Pediatria , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade , Sístole
12.
Cell Death Dis ; 9(11): 1074, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30341282

RESUMO

Tumor Treating Fields (TTFields), an approved treatment modality for glioblastoma, are delivered via non-invasive application of low-intensity, intermediate-frequency, alternating electric fields. TTFields application leads to abnormal mitosis, aneuploidy, and increased cell granularity, which are often associated with enhancement of autophagy. In this work, we evaluated whether TTFields effected the regulation of autophagy in glioma cells. We found that autophagy is upregulated in glioma cells treated with TTFields as demonstrated by immunoblot analysis of the lipidated microtubule-associated protein light chain 3 (LC3-II). Fluorescence and transmission electron microscopy demonstrated the presence of LC3 puncta and typical autophagosome-like structures in TTFields-treated cells. Utilizing time-lapse microscopy, we found that the significant increase in the formation of LC3 puncta was specific to cells that divided during TTFields application. Evaluation of selected cell stress parameters revealed an increase in the expression of the endoplasmic reticulum (ER) stress marker GRP78 and decreased intracellular ATP levels, both of which are indicative of increased proteotoxic stress. Pathway analysis demonstrated that TTFields-induced upregulation of autophagy is dependent on AMP-activated protein kinase (AMPK) activation. Depletion of AMPK or autophagy-related protein 7 (ATG7) inhibited the upregulation of autophagy in response to TTFields, as well as sensitized cells to the treatment, suggesting that cancer cells utilize autophagy as a resistance mechanism to TTFields. Combining TTFields with the autophagy inhibitor chloroquine (CQ) resulted in a significant dose-dependent reduction in cell growth compared with either TTFields or CQ alone. These results suggest that dividing cells upregulate autophagy in response to aneuploidy and ER stress induced by TTFields, and that AMPK serves as a key regulator of this process.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Neoplasias Encefálicas/patologia , Estimulação Elétrica/métodos , Glioblastoma/patologia , Regulação para Cima , Trifosfato de Adenosina/metabolismo , Aneuploidia , Animais , Autofagossomos/metabolismo , Proteína 7 Relacionada à Autofagia/antagonistas & inibidores , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Sobrevivência Celular , Terapia por Estimulação Elétrica , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Glioblastoma/terapia , Proteínas de Choque Térmico/metabolismo , Humanos , Lisossomos/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Mitose , Ratos , Fator A de Crescimento do Endotélio Vascular
13.
Radiat Oncol ; 12(1): 206, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29284495

RESUMO

BACKGROUND: Tumor Treating Fields (TTFields) are an anti-neoplastic treatment modality delivered via application of alternating electric fields using insulated transducer arrays placed directly on the skin in the region surrounding the tumor. A Phase 3 clinical trial has demonstrated the effectiveness of continuous TTFields application in patients with glioblastoma during maintenance treatment with Temozolomide. The goal of this study was to evaluate the efficacy of combining TTFields with radiation treatment (RT) in glioma cells. We also examined the effect of TTFields transducer arrays on RT distribution in a phantom model and the impact on rat skin toxicity. METHODS: The efficacy of TTFields application after induction of DNA damage by RT or bleomycin was tested in U-118 MG and LN-18 glioma cells. The alkaline comet assay was used to measure repair of DNA lesions. Repair of DNA double strand breaks (DSBs) were assessed by analyzing γH2AX or Rad51 foci. DNA damage and repair signaled by the activation pattern of phospho-ATM (pS1981) and phospho-DNA-PKcs (pS2056) was evaluated by immunoblotting. The absorption of the RT energy by transducer arrays was measured by applying RT through arrays placed on a solid-state phantom. Skin toxicities were tested in rats irradiated daily through the arrays with 2Gy (total dose of 20Gy). RESULTS: TTFields synergistically enhanced the efficacy of RT in glioma cells. Application of TTFields to irradiated cells impaired repair of irradiation- or chemically-induced DNA damage, possibly by blocking homologous recombination repair. Transducer arrays presence caused a minor reduction in RT intensity at 20 mm and 60 mm below the arrays, but led to a significant increase in RT dosage at the phantom surface jeopardizing the "skin sparing effect". Nevertheless, transducer arrays placed on the rat skin during RT did not lead to additional skin reactions. CONCLUSIONS: Administration of TTFields after RT increases glioma cells treatment efficacy possibly by inhibition of DNA damage repair. These preclinical results support the application of TTFields therapy immediately after RT as a viable regimen to enhance RT outcome. Phantom measurements and animal models imply that it may be possible to leave the transducer arrays in place during RT without increasing skin toxicities.


Assuntos
Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA/efeitos da radiação , Terapia por Estimulação Elétrica , Glioma/radioterapia , Imagens de Fantasmas , Dermatopatias/prevenção & controle , Animais , Glioma/genética , Glioma/patologia , Humanos , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
14.
JAMA ; 318(23): 2306-2316, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29260225

RESUMO

Importance: Tumor-treating fields (TTFields) is an antimitotic treatment modality that interferes with glioblastoma cell division and organelle assembly by delivering low-intensity alternating electric fields to the tumor. Objective: To investigate whether TTFields improves progression-free and overall survival of patients with glioblastoma, a fatal disease that commonly recurs at the initial tumor site or in the central nervous system. Design, Setting, and Participants: In this randomized, open-label trial, 695 patients with glioblastoma whose tumor was resected or biopsied and had completed concomitant radiochemotherapy (median time from diagnosis to randomization, 3.8 months) were enrolled at 83 centers (July 2009-2014) and followed up through December 2016. A preliminary report from this trial was published in 2015; this report describes the final analysis. Interventions: Patients were randomized 2:1 to TTFields plus maintenance temozolomide chemotherapy (n = 466) or temozolomide alone (n = 229). The TTFields, consisting of low-intensity, 200 kHz frequency, alternating electric fields, was delivered (≥ 18 hours/d) via 4 transducer arrays on the shaved scalp and connected to a portable device. Temozolomide was administered to both groups (150-200 mg/m2) for 5 days per 28-day cycle (6-12 cycles). Main Outcomes and Measures: Progression-free survival (tested at α = .046). The secondary end point was overall survival (tested hierarchically at α = .048). Analyses were performed for the intent-to-treat population. Adverse events were compared by group. Results: Of the 695 randomized patients (median age, 56 years; IQR, 48-63; 473 men [68%]), 637 (92%) completed the trial. Median progression-free survival from randomization was 6.7 months in the TTFields-temozolomide group and 4.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.52-0.76; P < .001). Median overall survival was 20.9 months in the TTFields-temozolomide group vs 16.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.53-0.76; P < .001). Systemic adverse event frequency was 48% in the TTFields-temozolomide group and 44% in the temozolomide-alone group. Mild to moderate skin toxicity underneath the transducer arrays occurred in 52% of patients who received TTFields-temozolomide vs no patients who received temozolomide alone. Conclusions and Relevance: In the final analysis of this randomized clinical trial of patients with glioblastoma who had received standard radiochemotherapy, the addition of TTFields to maintenance temozolomide chemotherapy vs maintenance temozolomide alone, resulted in statistically significant improvement in progression-free survival and overall survival. These results are consistent with the previous interim analysis. Trial Registration: clinicaltrials.gov Identifier: NCT00916409.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Terapia por Estimulação Elétrica , Glioblastoma/tratamento farmacológico , Adulto , Idoso , Antineoplásicos Alquilantes/efeitos adversos , Quimiorradioterapia , Dacarbazina/efeitos adversos , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Feminino , Seguimentos , Glioblastoma/radioterapia , Glioblastoma/cirurgia , Humanos , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Mitose , Análise de Sobrevida , Temozolomida
15.
J Vis Exp ; (123)2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28518093

RESUMO

Tumor Treating Fields (TTFields) are an effective treatment modality delivered via the continuous, noninvasive application of low-intensity (1-3 V/cm), alternating electric fields in the frequency range of several hundred kHz. The study of TTFields in tissue culture is carried out using the TTFields in vitro application system, which allows for the application of electric fields of varying frequencies and intensities to ceramic Petri dishes with a high dielectric constant (Ɛ > 5,000). Cancerous cell lines plated on coverslips at the bottom of the ceramic Petri dishes are subjected to TTFields delivered in two orthogonal directions at various frequencies to facilitate treatment outcome tests, such as cell counts and clonogenic assays. The results presented in this report demonstrate that the optimal frequency of the TTFields with respect to both cell counts and clonogenic assays is 200 kHz for both ovarian and glioma cells.


Assuntos
Ensaio de Unidades Formadoras de Colônias/métodos , Terapia por Estimulação Elétrica , Eletricidade , Glioma/terapia , Neoplasias Ovarianas/terapia , Protocolos Antineoplásicos , Linhagem Celular Tumoral , Feminino , Humanos , Resultado do Tratamento
16.
J Clin Monit Comput ; 31(5): 903-910, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27541954

RESUMO

Transthoracic Parametric Doppler (TPD) is a novel ultrasound technique recently developed for the investigation of pulmonary blood vessels. Lung Doppler Signals (LDS) recorded from TPD provide information regarding the functional mechanical characteristics of pulmonary blood vessels. We aimed to define the specific profile of LDS generated from TPD imaging in patients with pulmonary hypertension (PH), and to evaluate the diagnostic performance of LDS to detect PH using right heart catheterization (RHC) as gold standard reference. Seventy nine PH patients and 79 healthy controls matched for age, gender and BMI were recruited in a prospective case-control multicenter study. LDS recordings were performed by TPD consisting of a pulsed Doppler with a 2 MHz single element transducer. LDS were recorded within 24 h of RHC. Following LDS extraction, classification and performance evaluation were performed offline using a support vector machine (k-fold cross validation method). The best LDS parameters for PH detection were (1) peak velocity of the systolic (S) and diastolic (D) signals, (2) the rise slope of the S and D signals, and (3) time to peak of the S signal. Overall, the sensitivity and specificity of TPD for detection of PH were 82.7 % (95 % CI 81.3-84.1) and 87.4 % (95 % CI 86.3-88.5), respectively, with an area under the receiver operating curve of 0.95 (95 % CI 0.94-0.96). Detection rate of PH increased progressively with the level of mean pulmonary artery pressure. LDS recorded by TPD display a specific profile in PH and appears to be a promising and reliable tool for PH diagnosis. Further studies are required to confirm the clinical usefulness of LDS.


Assuntos
Diagnóstico por Computador/métodos , Ecocardiografia Doppler/métodos , Hipertensão Pulmonar/diagnóstico por imagem , Pulmão/fisiopatologia , Pressão Propulsora Pulmonar , Adulto , Idoso , Área Sob a Curva , Vasos Sanguíneos , Cateterismo Cardíaco , Estudos de Casos e Controles , Análise por Conglomerados , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia , Curva ROC , Projetos de Pesquisa , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
17.
Int J Cancer ; 139(12): 2850-2858, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27561100

RESUMO

Long-term survival rates for advanced ovarian cancer patients have not changed appreciably over the past four decades; therefore, development of new, effective treatment modalities remains a high priority. Tumor Treating Fields (TTFields), a clinically active anticancer modality utilize low-intensity, intermediate frequency, alternating electric fields. The goal of this study was to evaluate the efficacy of combining TTFields with paclitaxel against ovarian cancer cells in vitro and in vivo. In vitro application of TTFields on human ovarian cancer cell lines led to a significant reduction in cell counts as compared to untreated cells. The effect was found to be frequency and intensity dependent. Further reduction in the number of viable cells was achieved when TTFields treatment was combined with paclitaxel. The in vivo effect of the combined treatment was tested in mice orthotopically implanted with MOSE-LTICv cells. In this model, combined treatment led to a significant reduction in tumor luminescence and in tumor weight as compared to untreated mice. The feasibility of effective local delivery of TTFields to the human abdomen was examined using finite element mesh simulations performed using the Sim4life software. These simulations demonstrated that electric fields intensities inside and in the vicinity of the ovaries of a realistic human computational phantom are about 1 and 2 V/cm pk-pk, respectively, which is within the range of intensities required for TTFields effect. These results suggest that prospective clinical investigation of the combination of TTFields and paclitaxel is warranted.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Terapia Combinada , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/terapia , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 2357-2360, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28268799

RESUMO

Tumor Treating Fields (TTFields) are low intensity alternating electric fields in the 100-500 KHz frequency range that are known to have an anti-mitotic effect on cancerous cells. In the USA, TTFields are approved by the Food and Drug Administration (FDA) for the treatment of glioblastoma (GBM) in both the newly diagnosed and recurrent settings. Optimizing treatment with TTFields requires a deep understanding of how TTFields distribute within the brain. To address this issue, simulations using realistic head models have been performed. However, the preparation of such models is time-consuming and requires a high level of expertise, limiting the usefulness of these models for systematic studies in which the testing of multiple cases is required. Here we present a platform for rapidly simulating TTFields distributions in multiple scenarios. This platform enables high throughput computational simulations to be performed, allowing comparison of field distributions within the head in multiple clinically relevant scenarios. The simulation setup is simple and intuitive, allowing non-expert users to run simulations and evaluate results, thereby providing a valuable tool for studying how to optimize TTFields delivery in the clinic.


Assuntos
Neoplasias Encefálicas/terapia , Terapia por Estimulação Elétrica , Glioblastoma/terapia , Encéfalo , Simulação por Computador , Eletricidade , Cabeça , Humanos , Modelos Teóricos
19.
Sci Rep ; 5: 18046, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26658786

RESUMO

Tumor Treating Fields (TTFields) are low intensity, intermediate frequency, alternating electric fields. TTFields are a unique anti-mitotic treatment modality delivered in a continuous, noninvasive manner to the region of a tumor. It was previously postulated that by exerting directional forces on highly polar intracellular elements during mitosis, TTFields could disrupt the normal assembly of spindle microtubules. However there is limited evidence directly linking TTFields to an effect on microtubules. Here we report that TTFields decrease the ratio between polymerized and total tubulin, and prevent proper mitotic spindle assembly. The aberrant mitotic events induced by TTFields lead to abnormal chromosome segregation, cellular multinucleation, and caspase dependent apoptosis of daughter cells. The effect of TTFields on cell viability and clonogenic survival substantially depends upon the cell division rate. We show that by extending the duration of exposure to TTFields, slowly dividing cells can be affected to a similar extent as rapidly dividing cells.


Assuntos
Segregação de Cromossomos/fisiologia , Mitose/fisiologia , Neoplasias/patologia , Fuso Acromático/patologia , Animais , Apoptose/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Eletricidade , Humanos , Células MCF-7 , Microtúbulos/metabolismo , Microtúbulos/patologia , Neoplasias/metabolismo , Ratos , Ratos Endogâmicos F344 , Tubulina (Proteína)/metabolismo
20.
JAMA ; 314(23): 2535-43, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26670971

RESUMO

IMPORTANCE: Glioblastoma is the most devastating primary malignancy of the central nervous system in adults. Most patients die within 1 to 2 years of diagnosis. Tumor-treating fields (TTFields) are a locoregionally delivered antimitotic treatment that interferes with cell division and organelle assembly. OBJECTIVE: To evaluate the efficacy and safety of TTFields used in combination with temozolomide maintenance treatment after chemoradiation therapy for patients with glioblastoma. DESIGN, SETTING, AND PARTICIPANTS: After completion of chemoradiotherapy, patients with glioblastoma were randomized (2:1) to receive maintenance treatment with either TTFields plus temozolomide (n = 466) or temozolomide alone (n = 229) (median time from diagnosis to randomization, 3.8 months in both groups). The study enrolled 695 of the planned 700 patients between July 2009 and November 2014 at 83 centers in the United States, Canada, Europe, Israel, and South Korea. The trial was terminated based on the results of this planned interim analysis. INTERVENTIONS: Treatment with TTFields was delivered continuously (>18 hours/day) via 4 transducer arrays placed on the shaved scalp and connected to a portable medical device. Temozolomide (150-200 mg/m2/d) was given for 5 days of each 28-day cycle. MAIN OUTCOMES AND MEASURES: The primary end point was progression-free survival in the intent-to-treat population (significance threshold of .01) with overall survival in the per-protocol population (n = 280) as a powered secondary end point (significance threshold of .006). This prespecified interim analysis was to be conducted on the first 315 patients after at least 18 months of follow-up. RESULTS: The interim analysis included 210 patients randomized to TTFields plus temozolomide and 105 randomized to temozolomide alone, and was conducted at a median follow-up of 38 months (range, 18-60 months). Median progression-free survival in the intent-to-treat population was 7.1 months (95% CI, 5.9-8.2 months) in the TTFields plus temozolomide group and 4.0 months (95% CI, 3.3-5.2 months) in the temozolomide alone group (hazard ratio [HR], 0.62 [98.7% CI, 0.43-0.89]; P = .001). Median overall survival in the per-protocol population was 20.5 months (95% CI, 16.7-25.0 months) in the TTFields plus temozolomide group (n = 196) and 15.6 months (95% CI, 13.3-19.1 months) in the temozolomide alone group (n = 84) (HR, 0.64 [99.4% CI, 0.42-0.98]; P = .004). CONCLUSIONS AND RELEVANCE: In this interim analysis of 315 patients with glioblastoma who had completed standard chemoradiation therapy, adding TTFields to maintenance temozolomide chemotherapy significantly prolonged progression-free and overall survival. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00916409.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/terapia , Dacarbazina/análogos & derivados , Terapia por Estimulação Elétrica/métodos , Glioblastoma/terapia , Quimioterapia de Manutenção/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Canadá , Carmustina/uso terapêutico , Quimiorradioterapia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Dacarbazina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Término Precoce de Ensaios Clínicos , Terapia por Estimulação Elétrica/efeitos adversos , Europa (Continente) , Feminino , Glioblastoma/mortalidade , Humanos , Israel , Masculino , Pessoa de Meia-Idade , República da Coreia , Temozolomida , Estados Unidos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA