Circulating tumor cells (CTCs) are cancer cells that have been shed from a primary tumor and circulate in the bloodstream during progression of cancer. They may thus serve as circulating biomarkers that can predict, diagnose and guide therapy. Moreover, phenotypic and genotypic analysis of CTCs can facilitate prospective assessment of mutations and enable personalized treatment. A number of methodologies based on biological and physical differences between circulating tumor and non-tumor cells have been developed over the past few years. However, these methods did not have sufficient sensitivity or specificity. In this work, a remote analysis protocol was designed using motion microscopy that amplifies cellular micro motions in a captured video by re-rendering small motions to generate extreme magnified visuals to detect dynamic motions that are not otherwise visible by naked eye. Intriguingly, motion microscopy demonstrated fluctuations around breast tumor cells, which we referred to herein as cellular trail. Phenomena of cellular trail mostly emerged between 0.5 and 1.5 Hz on amplified video images. Interestingly, cellular trails were associated with cell surface proteins and flow rates rather than mitochondrial activity. Moreover, cellular trails were present only around circulating tumor cells from individuals with breast cancer under conditions of 20–30 μm/s and 0.5–1.5 Hz. Thus, motion microscopy based CTC detection method can offer a valuable supplementary diagnostic tool for assessment of drug efficacy and identifying physical characteristics of tumor cells for further research.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government ( MIST ) ( 2019R1C1C1003384 and 2010-0027945 ) and Ewha Womans University Research Grant of 2018. We thank medical students (Sunbeen Kim, Seoyeong Jung, and Eun young Baek) of Ewha University for helping to culture tumor cells.
© 2020 Elsevier B.V.
- Breast cancer
- Circulating tumor cells
- Computational tool
- Microfluidic system
- Motion microscopy