M6A methylation in tumor immune microenvironment: Multidimensional mechanism and targeted therapy strategies

N6-methyladenosine (m 6 A) modification, a dynamic and reversible post-transcriptional RNA alteration, plays a critical role in the precise regulation of gene expression and is fundamentally implicated in the interplay between tumor cells and the immune system. This review focuses on the regulatory mechanisms of m 6 A methylation in tumor immunology. We examine how m 6 A modifications within tumor cells reprogram the tumor immune microenvironment by modulating immune checkpoints, canonical signaling pathways, and cytokine secretion, as well as directly regulating immune-related genes. Crucially, we also dissect how m 6 A modification within immune cells shapes the immune microenvironment. Furthermore, we propose novel therapeutic strategies combining m 6 A targeting with immunotherapy. Collectively, this review provides novel insights into the role of m 6 A methylation in tumor immunology and paves the way for future research directions. • M 6 A regulates tumor immunity via PD-1/PD-L1, pathways, cytokines & immune gene sculpting. • M 6 A effects are context-specific: promotes immune escape or vulnerability across cancers. • Targeting m 6 A regulators/oncogenic pathways + immunotherapy enhances anti-tumor efficacy. • M 6 A within immune cells (lymphocytes/myeloid) critically shapes the anti-tumor response. • Precision targeting reader-downstream effector links is key for clinical m6A immunotherapy.