Lipid accumulation-mediated histone hypoacetylation drives persistent NK cell dysfunction in anti-tumor immunity

Hyperlipidemia impairs anti-tumor immune responses and is closely associated with increased human can-cer incidence and mortality. However, the underlying mechanisms are not well understood. In the present study, we show that natural killer (NK) cells isolated from high-fat-diet mice or treated with oleic acid (OA) in vitro exhibit sustainable functional defects even after removal from hyperlipidemic milieu. This is accom-panied by reduced chromatin accessibility in the promoter region of NK cell effector molecules. Mechanisti-cally, OA exposure blunts P300-mediated c-Myc acetylation and shortens its protein half-life in NK cells, which in turn reduces P300 accumulation and H3K27 acetylation and leads to persistent NK cell dysfunction. NK cells engineered with hyperacetylated c-Myc mutants surmount the suppressive effect of hyperlipidemia and display superior anti-tumor activity. Our findings reveal the persistent dysfunction of NK cells in dyslipi-demia milieu and extend engineered NK cells as a promising strategy for tumor immunotherapy.

Automated summary

This study reveals the persistent dysfunction of NK cells in a hyperlipidemia environment and demonstrates that exposure to oleic acid impairs NK cell function by inhibiting c-Myc acetylation. Moreover, it shows that engineered NK cells with hyperacetylated c-Myc mutants display superior anti-tumor activity.