Although the mechanistic background (for overview see [170]) is not fully clarified, HLA-G expression or the release of sHLA-G molecules are found to be upregulated in response of IFN-α, IFN-β, and IFN-γ by trophoblasts, blood, and tumor cells [18, 168, 171–173] as well as in response to IL-10 and TGFβ [169, 174]. Here, HLA-G is linked to neoplasm.