MAP2K1 and gastric cancer: In conclusion, our study found several ceRNA (circRNA–miRNA–immune-related mRNA) regulatory networks including hsa_circ_0050102–hsa-miR-4537–NRAS–Tgd cells, hsa_circ_0001013–hsa-miR-485-3p–MAP2K1–Tgd cells, hsa_circ_0003763–hsa-miR-145-5p–FGF10–StromaScore, hsa_circ_0001789–hsa-miR-1269b–MET–adipocytes, hsa_circ_0040573–hsa-miR-3686–RAC1–Tgd cells, and hsa_circ_0006089–hsa-miR-5584-3p–LYN–neurons in GC, among which FGF10, MET, NRAS, RAC1, MAP2K1, and LYN had a potential diagnostic value for GC patients.