Fig. 6
From: COX-2 expression positively correlates with PD-L1 expression in human melanoma cells
Down-regulation of PD-L1 by celecoxib in BRAFV600E and NRASQ61R melanoma cell lines. BRAFV600E A375 and NRASQ61R SK-MEL-2 melanoma cells were seeded at the density of 4 × 105 per well in a 75 cm2 tissue culture flask and incubated with celecoxib (60 μM). Untreated cells were used as a control. DMSO (vehicle of celecoxib) concentration was maintained at 0.02% in all wells. a Following a 24 h incubation at 37 °C in a 5% CO2 atmosphere, cells were harvested and lysed. Cell lysates were analyzed by western blot with the indicated mAbs. PD-L1 was detected using the PD-L1-specific mAb (clone SP-142). GAPDH was used as a loading control. Representative results are shown (upper panel). The levels of PD-L1 normalized to GAPDH are plotted and expressed as mean ± SD of the results obtained in three independent experiments (bottom panel). *** indicate P < 0.001. b Following a 24 h incubation at 37 °C in a 5% CO2 atmosphere, cells were harvested and cell surface stained with the PE-conjugated PD-L1-specific mouse mAb [clone MIH1 (RUO)]. PE-conjugated mouse IgG1 was used as a specificity control. Representative results are shown