The former comprises the killer cell immunoglobulin-like receptors (KIR)2D and the natural killer group 2 member (NKG2)A which recognize human leukocyte antigens (HLA), that can be downregulated by tumor and virus-infected cells to escape T cell recognition, and non-HLA-recognizing receptors, such as the Lectin-like Transcript-1 (LLT-1), which binds to NKRP1A. This evidence concerns the gene KLRC1 and neoplasm.