RSNA 2019

Abstract Archives of the RSNA, 2019


SSA23-05

Radiosensitization of Human Cancer Cells in Vitro with Focused Ultrasound Induced Hyperthermia

Sunday, Dec. 1 11:25AM - 11:35AM Room: S502AB



Participants
Xinrui Zhang, Leipzig, Germany (Abstract Co-Author) Nothing to Disclose
Michael Unger, Leipzig, Germany (Abstract Co-Author) Nothing to Disclose
Ina Patties, Leipzig, Germany (Abstract Co-Author) Nothing to Disclose
Lisa Landgraf, Leipzig, Germany (Abstract Co-Author) Nothing to Disclose
Andreas Melzer, MD, DDS, Dundee, United Kingdom (Presenter) Nothing to Disclose

For information about this presentation, contact:

xinrui.zhang@medizin.uni-leipzig.de

PURPOSE

Hyperthermia (HT; 40-46°C) is known to sensitize cancer cells to radiation therapy (RT) but the temperature rise cannot be quantified clinically. MR guided Focused ultrasound (MR-FUS) allows to generate local HT in a quantifiable way. In this study, impact of combined FUS-HT and RT treatment on human cancer cells was investigated in vitro to provide the base of the clinical use.

METHOD AND MATERIALS

Human glioblastoma (T98G) and prostate (PC-3) cancer cells were seeded in ultrasound-penetrable 96-well plates (Greiner Bio One). We have used a special sonicator for cell culture plates developed at IMSaT (University Dundee) and modified by us comprised by a programmable VXM motor controller and a NEMA 17 stepper motor (VELMEX Inc.). FUS-HT (45°C, 30 min) was induced with a customized 1.14 MHz transducer at 214 W/cm2. Temperature was monitored by thermal camera (Optris). HT (45°C, 30 min) in incubator worked as control. Single RT was applied at 10 Gy with an X-Ray device (DARPAC 150-MC; 1.28 Gy/min) within 60 min after RT. Effects on metabolic activity (WST-1, Roche) and DNA double-strand breaks (γH2A.X, Cell signalling) were evaluated.

RESULTS

Combination of FUS-HT and RT leads to decreased metabolic activity (T98G: 52 %; PC-3: 45 %) compared to single RT (T98G: 72 %; PC-3: 76 %) 72h after treatment. In contrast, classic HT+RT reduced metabolic activity to a lower extend (T98G: 57 %; PC-3: 50 %). FUS-HT combined with RT significantly (p < 0.05) enhance the number of initial DNA double-strand breaks (T98G: 21; PC-3: 11 foci/nucleus) compared to RT alone (T98G: 14; PC-3: 6 foci/nucleus) 1h post treatment.

CONCLUSION

Our data imply that FUS-HT shows potential to radiosensitize cancer cells. Increased DNA damage suggests an inhibition of repair mechanism and is further investigated. A new in vitro high throughput FUS system will now be completed.

CLINICAL RELEVANCE/APPLICATION

Focused ultrasound is an non-invasive way to generate precise local hyperthermia and sensitize cancer cells for radiation therapy or chemotherapy by synergistic effect.

Printed on: 03/01/22