PVR and melanoma: Therefore, CAFs could inhibit the killing activity of NK cells through downregulation PVR on the cell surface, which further promoted cancer development.66 Additionally, Zhang et al reported that CAFs secreted IL‐8 to attract monocytes and promoted M2 macrophages polarization.67 Furthermore, the synergetic effects of CAFs and TAMs, which induced by CAFs increasing the suppression of NK cells functions in colorectal cancer.67 In addition, CAFs significantly suppressed the cytotoxicity function of NK cells via releasing PGE2 in melanoma.68