CSB Seminar – Professor Jody Rosenblatt, University of Utah

What links cell division to cell death in order to maintain constant epithelial cell densities? We found that mechanical forces control both processes: cell stretching triggers rapid cell division, whereas, crowding causes cell death by a process we call ‘epithelial extrusion’, in which cells fated to die are seamlessly squeezed out from epithelia. Extrusion is essential for maintaining correct epithelial cell densities. We are finding a growing number of diseases result from misregulation of extrusion. Excessive extrusion disrupts epithelial barrier, causing inflammation and infection hyper-sensitivity after an asthma attack. Conversely, oncogenic mutations hijack apical extrusion signaling and promote a class of aggressive tumors, which invade via a new mechanism—basal extrusion.