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Fadul, J.

Publications and source records attributed to Fadul, J..

2 recordsLinked to original sources

Physical confinement promotes mesenchymal trans-differentiation of invading transformed cells in vivo

Metastasis is tightly linked with poor cancer prognosis, yet it is not clear how transformed cells become invasive carcinomas. We previously discovered that single KRasV12-transformed cells can invade directly from the epithelium by basal cell extrusion. During this process, cells de-differentiate by mechanically pinching off their epithelial determinants, but how they trans-differentiate into a migratory, mesenchymal phenotype is not known. Here, we demonstrate that basally extruded KRasV12-expressing cells become significantly deformed as they invade the zebrafish body. Decreasing the confinement that cells experience after they invade reduces the percentage of KRasV12 cells that trans-differentiate into mesenchymal cell types, while higher confinement increases this percentage. Additionally, increased confinement promotes accumulation of internal masses over time. Altogether, our results suggest that mechanical forces drive not only de-differentiation of KRasV12-transformed epithelial cells as they invade but also contribute to their re-differentiation into mesenchymal phenotypes that contribute to distant metastases.

cancer biology↗

Basal extrusion drives cell invasion and mechanical stripping of E-cadherin

Metastasis is the predominant reason that patients succumb to cancer, yet the mechanisms that drive initial tumor cell invasion are poorly understood. We previously discovered that crowding-induced apical extrusion drives most epithelial cell death, critical to maintaining constant cell densities. Oncogenic mutations can disrupt apical cell extrusion, instead causing masses to form and aberrant basal extrusion. Using transparent zebrafish epidermis to model simple epithelia, we can image invasion events live at high resolution. We find that KRas/p53-transformed cells form masses and, at completely independent sites, invade by basal extrusion. Basal extrusion also causes invading cells to simultaneously mechanically shed their entire apical membranes and E-cadherin. Once cells invade the underlying tissue, they migrate throughout the body, divide, enter the bloodstream, and become different cell types. KRas-transformation makes cells intrinsically invasive by increasing basal extrusion rates; collaborating mutations in p53 allow disseminated cells to survive at distant sites.

cancer biology↗