Cell Death, Compensatory Proliferation, and Cell Competition.

Abstract

Cell death, compensatory proliferation, and cell competition are fundamental interconnected processes that shape how tissues develop, maintain homeostasis, and regenerate. In this review, I highlight how cell death (apoptosis) not only eliminates excess and damaged cells but can also initiate compensatory proliferation, an adaptive response that occurs following cell loss. I examine cell competition, a quality-control mechanism that removes less fit loser cells in favor of healthier winner neighbors. Cell competition is intricately linked to cell death and compensatory proliferation. I present the history of these processes, discuss the most important examples, and reveal the key molecular mechanisms that underlie them. I incorporate findings from Caenorhabditis elegans, Drosophila melanogaster, vertebrates, and other models to underscore the conservation of the key molecular signaling events. I also discuss how misregulation of these processes can contribute to pathological conditions, including cancer.