The enrichment in immunosuppressive proteins, such as PD-L1, TGF-β, CTLA-4, CD39/CD73 or TRAIL, as well as paucity of immunostimulatory proteins, such OX40L or OX40, were in agreement with data previously reported by us and others for TEX from tumor cell supernatants [57,66]. This evidence concerns the gene CD274 and neoplasm.