CD90 mediates gastric cancer immune evasion though regulating IGF2BP2 to stabilize the m6A-CD47/SIRPα axis

As a cell surface glycoprotein, CD90 plays a significant role in the initiation and progression of malignancies such as gastric cancer (GC) by influencing tumor cell proliferation, migration, and angiogenesis. However, its specific role in immune evasion in GC and its potential therapeutic value have not been fully explored. In this study, we report that CD90 is highly expressed in GC tissues and is positively correlated with macrophage immune infiltration. Furthermore, we demonstrate that CD90 can mediate immune evasion in GC by affecting the phagocytic function of tumor-associated macrophages (TAMs). Mechanistically, CD90 functions as a scaffold protein, inhibiting the interaction between IGF2BP2 and TRIM21. This inhibition stabilizes the expression of the m6A methylation reader protein IGF2BP2. Subsequently, IGF2BP2 enhances the mRNA stability of the immune checkpoint molecule CD47 in an m6A-dependent manner, leading to the activation of the CD47/SIRPα axis. Ultimately, by inhibiting the phagocytic function of TAMs, CD90 mediates immune evasion in GC. In summary, our work highlights the critical role of the CD90-IGF2BP2-CD47 axis in immune evasion in GC. This finding is expected to provide significant experimental evidence for elucidating the pathogenesis of GC and discovering potential molecular targets for clinical treatment.