A new Nature Cell Biology study examines how embryonic cells protect their DNA while migrating through confined tissue spaces. Cell movement can subject the nucleus to strong mechanical deformation, creating a risk of DNA damage and genome instability. The authors identified a protective mechanism that helps migrating cells preserve nuclear integrity under these stresses. This finding may have implications for cancer, since tumor cells migrating through confined tissues experience similar nuclear deformation and DNA damage. Blocking these protective mechanisms could make invasive tumor cells less able to survive. (https://www.nature.com/articles/s41556-026-02065-w)