Entosis is a recently described nonapoptotic cell death mechanism that is initiated by the engulfment of live epithelial cells, leading to the formation of “cell-in-cell” structures. Entotic cell engulfment is induced by matrix detachment, and is driven by imbalances in actomyosin contraction between neighboring cells. Here we describe methods to quantify the formation of cell-in-cell structures by entosis, for cells cultured in suspension or in soft agar, by fluorescence imaging and time-lapse microscopy.
