Figure 5
Allopurinol blocks DNA damage-induced sensitization of PANC-1 cells to NK-92 cell killing. PANC-1 cells grown in 35-mm dishes were left untreated or treated with 5-FU (10 μM), gemcitabine (2 μM) or irradiated (40 Gy) in the absence or presence of allopurinol (250 μg/ml). After incubation for 20 hr, the cells were harvested and analyzed using a standard 51Cr release assay for NK-92 cell cytotoxic activity with a ratio of effector:target cells at 5:1 (A) or 1:1 (B). The data represent the mean ± SD from one of two experiments with similar results. AP, allopurinol; 5-FU, 5-fluorouracil; Gem, gemcitabine, IR, radiation.