Cell expansion after constricted migration reveals a growth delay. (A) Heatmaps summarize the bottom-to-top fold-change in percentage nuclear (Nucl.) blebs, DNA damage, and percentage 4N for 3- and 8-µm pore migration of both A549 and U2OS cells (log₂Ratio). (B) Schematics: Clonal A549 cells migrated through Transwells to a collagen coverslip placed under the Transwells with a ∼2-µm spacer, and the coverslips with sparsely attached cells were then transferred to standard cultures to monitor proliferation. (C) After migration through 8-µm pores, the population-average doubling time in colonies after transfer to a coverslip is similar to standard 2D growth (∼1.6 d, right curve, exponential fit, n > 4 experiments). However, after migration through 3-µm pores, a 0.85-d delay in growth is evident using the same 1.6-d doubling time. If the delay is set to zero, then the exponential fit with 1.6-d doubling time fits poorly (gray dashed fit, R² < 0.1). Scale bar: 20 µm.