CD44 and neoplasm: Lactylation reinforces pro-tumor macrophage functions through positive feedback loops: lactylation at the K316 site of glycolytic enzyme LDHA enhances its activity by 1.8-fold, further promoting lactate production (91); lactylation at the K116 site of TREM2 in tumor-associated macrophages (TAMs) strengthens its interaction with tumor cell CD44, facilitating the deposition of immunosuppressive extracellular matrix and inducing immune tolerance.