Fig. 2

Changes in Chk-α and PD-L1 mRNA levels are reflected in the total protein levels. a Representative immunoblot assays of Chk-α (top), PD-L1 (middle), and GAPDH (bottom) at 24, 48, and 72 h of siRNA incubation, respectively. b Percentage of MDA-MB-231 cancer cells expressing PD-L1 protein on their surface measured by flow cytometry. c The mean fluorescence intensity (MFI) of PD-L1 in MDA-MB-231 cancer cells. MDA-MB-231 cells were transfected with 100 nM scrambled siRNA, 100 nM luciferase siRNA, 100 nM Chk-α siRNA, or 100 nM PD-L1 siRNA #1, or with a mixture of 50 nM PD-L1 #1 and 50 nM Chk-α siRNA. Values are presented as box and whisker plots, with the middle line representing the mean and the whiskers representing the maximum to minimum data points from 3 to 6 independent experiments. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, compared to untreated cells. ^#p ≤ 0.05, ^##p ≤ 0.01, ^###p ≤ 0.001, compared to cells transfected with luciferase siRNA. ⁺p ≤ 0.05, ⁺⁺p ≤ 0.01, ⁺⁺⁺p ≤ 0.001, compared to cells transfected with scrambled siRNA (see also Supplementary Figure 2)