Tumor cells can utilize the major histocompatibility complex class I molecules transferred by platelets to evade immune surveillance 16, or platelet-derived transforming growth factor-β (TGFβ) can downregulate killer cell lectin like receptor K1 (encodes NKG2D) to inhibit the antitumor reactivity of NK cells 17. Here, KLRK1 is linked to neoplasm.