Nuclear and cellular plasticity: nuclear RAC1 takes center stage.

Navarro-Lérida et al. (2015) report in this issue of Developmental Cell that RAC1 nuclear accumulation causes actin-dependent deformation of the nuclear envelope and increases nuclear plasticity. It further leads to depletion of cytoplasmic, active RAC1 with a concomitant increase in RHOA signaling driving actomyosin-mediated cell shape changes. These two properties combine to enhance tumor cells invasiveness.