CD226 and melanoma: Finally, it is important to point out that a pioneer study involving CAFs isolated from melanoma, but also other studies involving hepatocellular and colorectal carcinoma-derived fibroblasts, have shown that these cells can decrease NKp30, NKp44, DNAM-1 and/or NKG2D expression at the surface of NK cells, as well as PFN or GzmB expression [34–36].