Single-Cell Local Stress Analysis in Tumoroids.

Data concerning the publication:Single-Cell Local Stress Analysis in Tumoroids

The reciprocal interplay between cancer cells and their local environment, mediated by mechanical forces, requires quantitative measurements of cellular forces within the intricate three-dimensional context of the extracellular matrix. Although methods such as traction-force microscopy and micropillar array technology have effectively reported on cellular forces in two-dimensional cell culture, extending these techniques to three dimensions has proven exceedingly challenging.    In the current study, we introduced an approach that utilizes soft, elastic hydrogel-microparticles, resembling the size of cells, to serve as specific and sensitive traction sensors in three-dimensional cell culture of collagen-embedded tumoroids. Our methodology relies on high-resolution detection of microparticle deformations, which are subsequently translated into spatially resolved traction fields, reaching micrometer spatial resolution and simultaneously detecting traction forces as low as 30 Pa.     Measurements enabled us to explore the relationships between cellular characteristics, extracellular traction fields, and cellular responses. We observed that cellular stresses ranged from 10 to 100 Pa, integrating to cellular forces from 0.1 to 100 nN. Forces were correlated with the localization of the cellular actin skeleton and the interaction area that cells developed toward the microparticles. Interestingly, the interaction of cells with inert microparticles appeared to be governed by contact mechanics resembling that of two soft spheres. We foresee the methodology developed here to provide insight about the role of mechanical cues in patient tumor progression in the future.