KLRK1 and neoplasm: As discussed in section Mechanisms Suppressing NK Cells in Myeloid Malignancies and Mediating Escape From NK Cell Recognition, one mechanism that has been put forward to explain impaired tumor immune surveillance by NK cells in myeloid malignancies is long-term exposure of soluble NKG2D ligands such as MICA, MICB, and ULBP2 secreted by the malignant blasts.