Fig. 3

Insulin but not EGF increases PD-L1 expression in non-CSCs. Insulin treatment can increase PD-L1 expression in non-cancer stem cells of HT-29 but the treatment needs to be 6 days to be able to display by Western blotting assay (a). In contrast, EGF treated HT-29 didn’t show PD-L1 protein band even after 6 days and only have the band after co-treatment with insulin. b shows a dose-dependent increase of PD-L1 protein from 1μg/ml to 20 μg/ml insulin. Like b, c shows the dose-dependent increase of PD-L1 by flow cytometry analysis