We treated cancer cells with dexamethasone and TWS-119, and found that dexamethasone can suppress PD-L1 and IDO1 expression in multiple cancer cell lines, including SGC-7901, MKN-45, SMMC-7721, and BxPC3 (Fig. 2A–2B and Supplementary Fig. S1B). Here, CD274 is linked to cancer.