This is of relevance since SHP-1 can provide PD-1-mediated downstream dephosphorylation in the absence of SHP-2 [237], while another IC molecule, the B and tumor activity of T cells T lymphocyte attenuator (BTLA) [238], has been reported to engage SHP-1 in preference to SHP-2 [239] to impair lymphocyte functionality. This evidence concerns the gene PTPN11 and neoplasm.