KIR3DL1 and neoplasm: This functional difference of NKG2C+ NK cells might be related to (i) increased CD16/FcγRIII expression, loss of FcεRIγ signaling adapter and favored signaling via CD3ζ and (ii) elevated inhibitory KIR expression inducing tolerance to tumor cells exhibiting protective amounts of HLA class I molecules [22,34,35].