EFNA3 and neoplasm: <i>In vitro</i> and <i>in vivo</i> experiments further demonstrated that EFNA3 promotes gastric cancer cell proliferation, migration, and tumor growth.<h4>Discussion</h4>Collectively, EFNA3 is closely linked to pro-tumor processes and immune evasion in gastric and multiple other cancers, supporting its value as a subtype biomarker and potential therapeutic target.