Fig. 4

Effect of PD-L1 inhibition on STAT3 and EGFR expression in HCT116-MR colon cancer cells. a. The mRNA expression levels of PD-L1, STAT3 and EGFR at 24 h, 48 h, and 72 h after transfection with a specific siRNA targeting PD-L1. One way anova test: **p < 0.002; ****p < 0.0001 compared with the control. b. Western blot analysis of cell signalling proteins in HCT116-MR cells transfected with a specific siRNA targeting PD-L1 or with a scrambled, control siRNA for 24, 48 and 72 h. Total cell protein extracts were subjected to immune-blotting with the indicated antibodies, as described in Materials and Methods