Beyond 2D: Collective Cell Migration and Topological Data Analysis

Epithelial cells transition between collective and individual migration during development and disease, analogous to interacting building blocks (dis)assembling as an active material. In this seminar, I will present recent results on my group to investigate so-called epithelial-mesenchymal transitions in the context of soft matter physics, mechanobiology, and machine learning. First, we investigate how mammary epithelial cells transition from a fluid-like “unjammed” phase to a solid-like “jammed” phase. We show that these collective behaviors exhibit striking analogies with a gelation-like mechanism during the diffusion limited aggregation of non-living colloidal particles. Second, we analyze the disorganization and dissemination of multicellular clusters cultured in 3D matrix, which exhibit both collective and individual invasion phenotypes with spatially non-uniform traction signatures. Third, we describe the use of topological barcodes for automated classification of tissue architecture based on spatial connectivity (i.e. persistent homology). These emergent phenomena in living and non-living systems exhibit striking similarities, which may enable new fundamental insights into the morphogenesis of tissues and tumors.