Tumor metabolite lactate promotes tumorigenesis by modulating MOESIN lactylation and enhancing TGF-β signaling in regulatory T cells

Regulatory T (Treg) cells play a vital role in maintaining the immunosuppressive tumor microenvironment. Lactate is a crucial metabolite in cancer and is related to tumor prognosis, metastasis, and overall survival. In this study, we focus on the effects of lactate on Treg cells. In vitro, lactate improves Treg cell stability and function, whereas lactate degradation reduces Treg cell induction, increases antitumor immunity, and decreases tumor growth in mice. Mechanistically, lactate modulates Treg cell generation through lactylation of Lys72 in MOESIN, which improves MOESIN interaction with transforming growth factor β (TGF-β) receptor I and downstream SMAD3 signaling. Cotreatment with anti-PD-1 and a…