After 24 hours of NK- cancer cell co-culture in EGTA, about 40% of U-2 OS cell death that were independent of granzyme-B FRET signal change still occurred (Figure 2A), suggesting that the granzyme-B independent killing by primary NK cells is largely induced by cytotoxic pathway(s) not involving lytic granule transfer. The gene discussed is GZMB; the disease is cancer.