ULBP3 and neoplasm: Although NKG2DLs such as MICA/B are widely expressed in many epithelial tumors and are associated with the regulation of NK and γδ T cells, which play a key role in the elimination of tumor cells32, other NKG2DLs, such as ULBP1, ULBP2, and ULBP3, are not well characterized.