Direct interactions between tumor and immune cells can result in suppression of natural killer (NK) cell activity mediated by HLA molecules (including HLA-E and HLA-G) (14), immune cell apoptosis via tumor necrosis factor receptor superfamily member 6 (TNFRSF6, known as FAS) and the FAS-ligand interaction (15), or triggering of inhibitory T cell checkpoints by PD-L1 (16). The gene discussed is FAS; the disease is neoplasm.