Epithelial–mesenchymal Transition (EMT) is a multi-step process that involves cytoskeletal rearrangement. Here, developing and using an image quantification tool, Statistical Parametrization of Cell Cytoskeleton (SPOCC), we have identified an intermediate EMT state with a specific cytoskeletal signature. We have been able to partition EMT into two steps: (1) initial formation of transverse arcs and dorsal stress fibers and (2) their subsequent conversion to ventral stress fibers with a concurrent alignment of fibers. Using the Orientational Order Parameter (OOP) as a figure of merit, we have been able to track EMT progression in live cells as well as characterize and quantify their cytoskeletal response to drugs. SPOCC has improved throughput and is non-destructive, making it a viable candidate for studying a broad range of biological processes. Further, owing to the increased stiffness (and by inference invasiveness) of the intermediate EMT phenotype compared to mesenchymal cells, our work can be instrumental in aiding the search for future treatment strategies that combat metastasis by specifically targeting the fiber alignment process.
Bibliographical noteFunding Information:
The authors thank Dr. Michael Lake for help with AFM experiments and Ms. Maya Segal for her help in the organization and writing of this manuscript. We acknowledge the support of the Nano and Pico Characterization Lab at California NanoSystems Institute for the AFM experiments. The research was supported by the STROBE National Science Foundation Science and Technology Center, Grant No. DMR-1548924 and Willard Chair funds.
© 2022, The Author(s).