FASLG and cancer: As shown in Fig. 3a, treatment with 400 ng/mL sFasL alone resulted in mild to moderate reduction in cancer cell viability (55.6%, 80.2%, 42.3%, 67.8%, 44.6%, and 59.9% in U87, PC3, BT549, A549, HepG2, and SUM159 cells, respectively, compared to the control).