Tumor Treating Fields Suppression of Ciliogenesis Enhances Temozolomide Toxicity

Tumor Treating Fields (TTFields) are low intensity, alternating intermediate frequency (200kHz) electrical fields that extend survival of glioblastoma patients receiving maintenance temozolomide (TMZ) chemotherapy. How TTFields exert efficacy on cancer over normal cells, or interact with TMZ is unclear. Primary cilia are microtubule-based organelles triggered by extracellular ligands, mechanical and electrical field stimulation, and are capable of promoting cancer growth and TMZ chemoresistance. We found in both low and high grade patient glioma cell lines that TTFields ablated cilia within 24 hours. Halting TTFields treatment led to recovered frequencies of elongated cilia. Cilia on normal primary astrocytes, neurons, and multiciliated/ependymal cells were less affected by TTFields. The TTFields-mediated loss of glioma cilia was partially rescued by chloroquine pretreatment, suggesting the effect is in part due to autophagy activation. We also observed death of ciliated cells during TTFields by live imaging. Notably, TMZ-induced stimulation of ciliogenesis in both adherent cells and gliomaspheres was blocked by TTFields. Moreover, the inhibitory effects of TTFields and TMZ on tumor cell recurrence correlated with the relative timing of TMZ exposure to TTFields and ARL13B+ cilia. Finally, TTFields disrupted cilia in patient tumors treated ex vivo. Our findings suggest TTFields efficacy may depend on the degree of tumor ciliogenesis and relative timing of TMZ treatment.

Health-Related Quality of Life for Patients Receiving Tumor Treating Fields for Glioblastoma

BackgroundTo date, there has been no large-scale, real-world study of the health-related quality of life outcomes for patients using tumor treating fields (TTFields) therapy for glioblastoma (GBM) treatment.MethodsA survey was mailed to 2,815 patients actively using TTFields for treatment of GBM in the USA (n = 2,182) and Europe (n = 633). The survey included patient-reported demographic and clinical information, as well as EuroQol’s EQ-5D-5L and visual analogue scale (EQ-VAS) overall health score.ResultsA total of 1,106 applicable patients responded to the survey (USA = 782 and Europe = 324), with a mean age of 58.6 years (SD = 12.3). The average time since diagnosis and time using TTFields were 21.5 months (SD = 25.1) and 13.5 months (SD = 13.2), respectively. Over 61% of patients had been diagnosed at least 1 year prior and 28.4% at least 2 years prior; 45 patients (4.2%) had been diagnosed at least 5 years prior. Progressed disease was reported in 307 patients, while 690 reported non-progressed disease. Regression analyses showed that GBM disease progression and older age had predictable negative associations (p < 0.001) with most EQ-5D-5L dimensions and the EQ-VAS. However, longer time since diagnosis was associated with improved self-care (p < 0.05), usual activities (p < 0.01), and EQ-VAS (p < 0.05) overall and in patients with progressed disease (p < 0.01, p < 0.05, and p < 0.01, respectively). Additionally, longer time using TTFields was associated with improved mobility (p < 0.05), self-care (p < 0.001), usual activities (p < 0.01), and EQ-VAS (p < 0.01) overall; with improved EQ-VAS in progression-free patients (p < 0.05); and with improved mobility (p < 0.05), self-care (p < 0.01), usual activities (p < 0.05), and EQ-VAS (p < 0.05) in patients with progressed disease.ConclusionThis is the largest real-world study of patient-reported quality of life in GBM and TTFields treatment to date. It shows unsurprising negative associations between quality of life and disease progression and older age, as well as more novel, positive associations between quality of life and longer time since diagnosis and time using TTFields therapy.

COT-7 Online supports for opening of the tumor treating field

Background: EF-14 trial showed the efficacy of tumor treating fields (TTF), and TTF was approved as a standard therapy for glioblastoma in Japan. In TTF opening, Device Support Specialist (DSS) explains how to use it for the patient and the family. Because there is no DSS in Yamaguchi prefecture, DSS has to come to our hospital across other prefectures. On the other hand, COVID-19 is still spreading and it is sometimes tough to move from a big city to countryside. Here, we would present the experiences of TTF opening with online DSS support. Method: From June 2020, Zoom was used for 4 patients, and from June 2021, iPad/Face-Time was used for one patient. TTF was introduced via online DSS support with direct support from our nurse in our out clinic. After that, initial times of TTF change were performed via online DSS support in patient’s home. Two patients who used Zoom had trouble to connect to internet, however finally completed with relative helps.Conclusion: Online medicine should be absolutely spreading in country sides. Now, we change from Zoom to iPad, because the old patients in country sides were hard to use internet utility. We should make efforts to provide patients more brief methods of online support.

Establishment of Tumor Treating Fields Combined With Mild Hyperthermia as Novel Supporting Therapy for Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor with poor prognosis and limited therapeutic options. Alternating electrical fields with low intensity called “Tumor Treating Fields” (TTFields) are a new, non-invasive approach with almost no side effects and phase 3 trials are ongoing in advanced PDAC. We evaluated TTFields in combination with mild hyperthermia. Three established human PDAC cell lines and an immortalized pancreatic duct cell line were treated with TTFields and hyperthermia at 38.5°C, followed by microscopy, assays for MTT, migration, colony and sphere formation, RT-qPCR, FACS, Western blot, microarray and bioinformatics, and in silico analysis using the online databases GSEA, KEGG, Cytoscape-String, and Kaplan-Meier Plotter. Whereas TTFields and hyperthermia alone had weak effects, their combination strongly inhibited the viability of malignant, but not those of nonmalignant cells. Progression features and the cell cycle were impaired, and autophagy was induced. The identified target genes were key players in autophagy, the cell cycle and DNA repair. The expression profiles of part of these target genes were significantly involved in the survival of PDAC patients. In conclusion, the combination of TTFields with mild hyperthermia results in greater efficacy without increased toxicity and could be easily clinically approved as supporting therapy.