Static magnetic fields in the treatment of EGFR-overexpressing tumors

Introduction:

Static magnetic fields (SMF) exhibit antitumoral activity in vitro and in vivo. Further, SMF enhance the efficacy of chemotherapy by opening the tumor-blood-barrier. However, the optimal SMF-exposure protocol is unknown. Further, there are no data whether SMF also improve the efficacy of EGFR-targeted tumor therapy. Therefore, this study aimed to analyse different SMF-exposure protocols on EGFR-overexpressing tumors, alone and in combination with cetuximab.

Methods:

Experiments were performed in dorsal skinfold chamber preparations of C57/Bl6- and CD1nu/nu-mice bearing Lewis Lung Carcinomas. Each study group was comprised of six mice. Animals were exposed to a SMF of 587 mT, either threefold for 2 hours every third day or for 35 minutes daily for 9 days. Some animals additionally received cetuximab injections. Using in vivo-fluorescence microscopy, tumor angiogenesis and microcirculation were analysed for 7 days. Tumor growth was assessed by repeated planimetry for 13 days.

Results:

Threefold SMF-exposure for 2 hours led to a significant reduction of tumor growth by 46% whereas daily short SMF-exposure intervals did not yield a significant tumor growth inhibition. Adding cetuximab to SMF-exposure did not result in any treatment benefit although cetuximab monotherapy was highly effective (tumor growth reduced by 53%). The different treatment schedules had no major influence on microcirculation and angiogenesis.

Conclusions:

SMF are a novel strategy in treating EGFR-overexpressing tumors: However, SMF exposure interferes with EGFR blockage.

Publication History

Publication Date:
18 April 2018 (online)