HLA-C and neoplasm: Inhibition of PTPN11 activity enhances tumor-intrinsic IFN-γ signaling, resulting in increased chemoattractant cytokine release and cytotoxic T cell recruitment, as well as increased expression of major histocompatibility complex (MHC) class I and programmed cell death ligand 1 (PD-L1) on the surface of cancer cells, along with decreased differentiation and suppression of immunosuppressive myeloid cells in the tumor microenvironment (208, 209).