Through RNA modifications or interactions, METTL16 may regulate the expression of key immune checkpoint molecules, such as programmed death-ligand 1 (PD-L1), cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), and T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), as well as immune stimulators and major histocompatibility complex (MHC) molecules, thereby affecting tumor immune evasion and the response to immunotherapy51,61, 127 (Fig. 5). The gene discussed is CTLA4; the disease is neoplasm.