Collective MAPK Signaling Dynamics Coordinates Epithelial Homeostasis

Epithelial tissues are constantly challenged by individual cell fate decisions while maintaining barrier function. During oncogenesis, mutant and normal cells also differ in their signaling states and cellular behaviors creating competitive interactions that are poorly understood. Here we show that the temporal patterns of MAPK activity are decoded by the ADAM17-EGFR paracrine signaling axis to coordinate migration of neighboring cells and promote extrusion of aberrantly-signaling cells. Concurrently, neighboring cells increase proliferation to maintain cell density while oncogene expressing cells undergo cell cycle arrest. Moreover, the stress MAPK p38 elicits the same paracrine signaling and extrusion response, suggesting that the ADAM17-EGFR pathway constitutes a quality control mechanism to eliminate and replace unfit cells from epithelial tissues. Overall, we show that the temporal patterns of MAPK activity coordinates both single and collective cell behaviors to maintain tissue homeostasis.