As mentioned before, we previously demonstrated that PPIs could promote PD‐L1 translocation onto cell membrane in a variety of tumor cells, while quantitative real‐time PCR results showed that PD‐L1 mRNA levels were not significantly changed after PPIs treatment (IFN‐β or IFN‐γ were used as positive controls) (Figure 3A; Figure S4C). This evidence concerns the gene IFNB1 and neoplasm.