PDTM-19. TUMOUR TREATING FIELDS (TTFIELDS) EXHIBIT EFFICACY ON HIGH-GRADE PAEDIATRIC BRAIN TUMOUR CELL LINES

摘要

INTRODUCTION The EF-14 trial of the Optune system which utilises Tumour Treating Fields (TTFields) has shown positive results in adult Glioblastoma multiforme (GBM) patients. These results have given strength to the feasibility of TTFields being added to existing chemotherapy and radiation therapy for brain tumour patients. Here we present the data showing the efficacy of TTFields on a panel of paediatric GBM, Medulloblastoma and Ependymoma cell lines. METHODS The Inovitro system is the laboratory testing system used to develop the clinically approved Optune system. Inovitro was used to deliver TTFields over a range of clinically relevant frequencies (100-400kHz) to our panel of high grade paediatric cell lines. The effects of TTFields on cell viability was assessed using metabolic viability tests, and cell cycle analysis was performed using flow cytometry. Gene expression analysis was performed via Affymetrix microarray. RESULTS TTFields have significant efficacy on all of our cell lines, and the extent of this is dependent upon frequency. Cells treated with TTFields were re-seeded and growth rates were compared to control cells. The treated cells experienced up to 75% slower growth rates following treatment. Cell cycle analysis revealed that TTFields treated cells have significantly greater levels of G2/M phase accumulation relative to control, and this coincides with previous observations in adult GBM cell lines. The efficacy of TTFields may be significantly increased with the addition of the mitotic inhibitor, paclitaxel. The effects of TTFields treatment on gene expression will be discussed. CONCLUSIONS TTFields treatment has demonstrated efficacy against our panel of paediatric GBM, Medulloblastoma and Ependymoma cell lines - further investigation is warranted so that this may be translated into the clinic.