Examination of infrasound-inducible chemo-sensitivity in head and neck tumour cells and its effect on their ultrastructure

Introduction Platinum-based chemotherapy is an important part of the treatment of head and neck cancer. Despite the growing field of targeted but comparatively expensive therapeutic approaches, further improvement of its therapeutic efficacy would be highly desirable and could benefit patients and bearers of costs. The aim of this study is to investigate whether head and neck tumour cells can be made more sensitive to cisplatin by exposure to infrasound. Some in vitro studies on other tumour entities have already shown promising results in this regard.

Method Head and neck squamous cell carcinoma cells (UD-SCC 5) were exposed to cisplatin (2.5 - 50 µl/ml, 4 d) alone and in combination with infrasound (18 Hz, 130 dB, 8 h). Colony forming assay was performed and further analysed using Image J and Chi² test. Additionally, the tumour cell ultrastructure was examined using transmission electron microscopy after infrasound exposure and cell fixation.

Results In transmission electron microscopy, all sonicated cells (n=12) showed fragmented nuclear membranes; occasionally they also exhibited damage to the cell membrane and stereocilia. Although more complex to assess due to the lack of spatial resolution, some deformed mitochondria, dictyosomes and endoplasmatic reticula could be shown. Anyhow, the differences between the sonicated and not sonicated group were not convincing in terms of colony forming behaviour (p=0.807).

Conclusion Promising results of previous studies on infrasound-inducible chemo-sensitivity could not be fully reaffirmed. However, changes in the cell and nuclear membrane were clearly detected. In summary, in our experimental setup no advantage of the addition of infrasound to chemotherapy in head and neck cancers can be derived so far.

Funding information Brigitte und Dr. Konstanze Wegener-Stiftung

Publication History

Article published online:
19 April 2024