Picking Winners and Losers: Cell Competition in Tissue Development and Homeostasis

Viable cells with reduced fitness are often eliminated by neighboring cells with greater fitness. This phenomenon, called cell competition, is an important mechanism for maintaining a high-quality population of cells in tissues. Foundational studies characterizing cellular competition and its molecular underpinnings were first carried out utilizing Drosophila as a model system. More recently, competitive behavior studies have extended into mammalian cell types. In this review, we highlight recent advances in the field, focusing on new insights into the molecular mechanisms regulating competitive behavior in various cellular contexts and in cancer. Throughout the review, we highlight new avenues to expand our understanding of the molecular underpinnings of cell competition and its role in tissue development and homeostasis.