Cell competition is a mechanism for cellular quality control based on cell–cell comparisons of fitness. Recent studies have unveiled a central and complex role for cell competition in cancer. Early tumors exploit cell competition to replace neighboring normal epithelial cells. Intestinal adenomas, for example, use cell competition to outcompete wild-type epithelial cells. However, oncogenic mutations do not always confer an advantage: wild-type cells can identify mutant cells and enforce their extrusion through cell competition, a process termed “epithelial defense against cancer”. A particularly interesting situation emerges in metastasis: supercompetitive tumor cells encounter heterotypic partners and engage in reciprocal competition with diverging outcomes. This article sheds light on the emerging complexity of cell competition by highlighting recent studies that unveil its context dependency. Finally, we propose that tissue histomorphology implies a crucial role for cell competition at tumor invasion fronts particularly in metastases, warranting increased attention in future studies.

细胞竞争是一种基于细胞间适应性比较的细胞质量控制机制。最近的研究揭示了细胞竞争在癌症中的核心而复杂的作用。早期肿瘤利用细胞竞争来取代邻近的正常上皮细胞。例如，肠腺瘤利用细胞竞争来战胜野生型上皮细胞。然而，致癌突变并不总是具有优势：野生型细胞可以识别突变细胞并通过细胞竞争强制将其挤出，这一过程称为“上皮细胞防御癌症”。转移中出现了一个特别有趣的情况：超级竞争的肿瘤细胞遇到异型伙伴并进行相互竞争，结果不同。本文通过重点介绍揭示细胞竞争环境依赖性的最新研究，揭示了细胞竞争日益显现的复杂性。最后，我们提出组织组织形态学意味着细胞竞争在肿瘤侵袭前沿尤其是转移中发挥着至关重要的作用，值得在未来的研究中给予更多关注。