Reinvigoration of exhausted T cells by ICI is associated with significant chromatin remodeling, suggesting that epigenetic manipulation may benefit some patients with exhausted T cell function.76 HDAC inhibitors inhibit activation-induced cell death (AICD) of T cells, and preclinical models indicate that HDAC inhibitors with ICI may prevent T cell death and enhance anti-tumor responses.77 Clinical trials utilizing this approach are enrolling. Here, HDAC9 is linked to neoplasm.