CTLA4 and neoplasm: In 2022, Lin et al. classified two GC phenotypes according to their exosome-based gene signatures, including glutathione peroxidase 3 (GPX3), regulator of G protein signaling 2 (RGS2), matrilin 3 (MATN3), solute carrier family 7 member 2 (SLC7A2), and synuclein gamma (SNCG), helping to predict tumor responses to an anti-CTLA4 inhibitor [103].