To verify whether the induction of IDO and PD-L1 expression by IL-27 was limited to EOC cells or was a common feature shared with other cancer cell types and normal cells, we tested PC3 prostate cancer cells and A549 lung adenocarcinoma cells, both of which were shown to respond to IL-27 stimulation, and human monocytes. Here, IDO1 is linked to lung adenocarcinoma.