Vice Chairman and Residency Program Director, Director, Kenneth R. Peak Brain and Pituitary Tumor Treatment Center Houston Methodist Hospital Houston, Texas, United States
Disclosure(s):
David S. Baskin, MD, FACS, FAANS: No financial relationships to disclose
Introduction: Noninvasive cancer therapy with minimal side effects would be ideal for improving patient outcome in the clinic. We have developed a novel therapy using strong spinning magnets mounted on a helmet to treat glioblastoma (GBM). They generate spin oscillating magnetic fields (sOMF) that penetrate through the skull and penetrate the entire brain.
Methods: Cell death analysis by clonogenic survival assay and reactive oxygen species (ROS) generation analysis with MitoSOX and dihydroethidium staining was done on cells exposed to sOMF. DNA damage was assessed by immunostaining for gamma-H2AX and 53BP1 in the DAPI stained nuclei. Flourescent microscope and flow-cytometer was used for acquisition of dye signals.
Results: We demonstrated that OMF can kill patient derived GBM cells in cell culture without having cytotoxic effects on cortical neurons and normal human astrocytes (NHA). Exposure of GBM cells to sOMF reduced cell survival by 40% to 50% in comparison to sham-treated cells, while not affecting SVGp12 cell survival. Fluorescence microscopy after sOMF exposure showed a marked elevation of mitochondrial ROS in GBM cells but not in normal astroglia cells. Addition of a potent antioxidant vitamin E analog Trolox blocked OMF-induced GBM cell death. Furthermore, sOMF caused significant DNA damage detected by high gH2AX and 53BP1 positive cells in GBM cells while normal astroglia SVGp12 cells showed no DNA damage induction. The results of our studies demonstrate that sOMF-induced cell death is mediated by ROS generation.
Conclusion : These results demonstrate a potent oncolytic effect on GBM cells that is novel and unrelated to any previously described therapy, including a different mechanism of action and different technology compared to OptuneTM therapy. The effect is powerful, and unlike OptuneTM, can be seen within hours after initiation of treatment. This exciting technology holds great promise for new, effective and nontoxic treatment of glioblastoma.
