br The cellular diffusivity D in MDA
The cellular diffusivity (D) in MDA-MB-231 HBX41108 was signifi-cantly upregulated with increasing vimentin expression for both cancer cells under both normoxic and hypoxic conditions. PCL substrate showed large D value (fourfold for normoxia and twofold
for hypoxia) at the same extent of expression in vimentin compared with that of PLLA substrate because the stiff substrate decreased cellular migration. The D values were upregulated with increasing deformability (ratio of AN and AC) under both oxygen concentration conditions. Our results found that the cellular diffusivity in MDA-MB-231 cells was not affected significantly by hypoxia. Hypoxia could slightly downregulate the cellular diffusivity, but the adverse effect is not significant when compared with normoxic condition. The diffusivity in MCF-7 cells under hypoxia was increased after they were treated with hypoxia in comparison to normoxia condition and provided the robust correlation between vimentin expression and D.
The cellular morphologies as potential parameters of under-standing in enhancing EMT emerged the possibility that the morphological differences were correlated with cellular motility and gene expression.
The article was written through contributions of all authors. All authors have given approval to the final version of the article.
Conflict of interest
The authors declare no competing financial interest.
This work was supported by the Grant in Toyota Technological Institute (TTI) as a Special Research Project (FY2017).
Appendix A. Supplementary data
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Materials Today Chemistry
Cellular morphologies, motility, and epithelialemesenchymal transition of breast cancer cells incubated on viscoelastic gel substrates in hypoxia
Advanced Polymeric Nanostructured Materials Engineering, Graduate School of Engineering, Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya, 468 8511, Japan
Received in revised form
The induction of epithelialemesenchymal transition (EMT) is believed to promote tumor cell motility and invasion. Using polymeric gel substrates with different viscoelasticity as microenvironment of cell culture substrates that influences cancer progression and metastatic potential, we have examined the effect of the viscoelasticity on the direct relation between cellular motility and mesenchymal properties with induction of EMT in MDA-MB-231 cells. The MDA-MB-231 cells cultured on gel substrates showed different cellular morphologies, and these morphological differences were robustly correlated with cellular migration speed (S) and damping coefficient (tand) of gel substrates (not substrate stiffness). The linkage between the acquisition of the mesenchymal phenotype in the cells through the induction of EMT mediated by a stiffer substrate and the promotion of cellular motility was not observed. Under-standing the biology of EMT with or without linkage to cellular motility provides new approaches in development of new therapeutic strategies.