Development and Optimisation of in vitro Sonodynamic Therapy for Glioblastoma

Background Sonodynamic therapy (SDT) is currently on critical path for glioblastoma therapeutics. However, the molecular mechanisms underlying the therapeutic functions of SDT remain enigmatic due to the lack of intricately optimised instrumentation capable of modulating SDT delivery in vitro. We established and validated an automated in vitro SDT system and assessed its SDT efficacy. Methods An automated in vitro SDT system was established and validated to allow the application and mapping of focused ultrasound fields under varied acoustic exposure conditions and setup configurations. Ultrasound field simulations were performed to assess the acoustic energy exposure. Systematic in vitro investigations were performed to optimise ultrasound frequency, intensity, plate base material, thermal effect, and the integration of live cells. Results In the presence of 5-ALA, focused ultrasound induces apoptotic cell death in primary patient-derived glioma cells with concurrent upregulation of intracellular reactive oxygen species. Intriguingly, primary glioma stem neurospheres also exhibit remarkably reduced 3D growth upon SDT exposure. Further, ultrasound field simulations performed established acoustic field distribution and the impact of acoustic standing waves within the well-plates. Conclusions The optimised in vitro SDT system and associated ultrasound field simulations establish the basis for further understanding of SDT and its therapeutic potentials in cancer. ### Competing Interest Statement The authors have declared no competing interest.