GZMB and cancer: While HG-3, PGA-1, and JVM-3 showed similar results in all experimental assays with a high susceptibility to NK cell-mediated lysis and high intracellular granzyme B load, MEC-1 cells demonstrated a high resistance to NK cell-mediated cytotoxicity and decreased uptake of NK cell-derived granzyme B. We attributed these differences to the relative size of the AR+ subpopulation as we were able to show that de novo F-actin polymerization on the cancer side of the IS is strongly associated with survival and resistance during NK cell attack.