EHMT2 and gastric cancer: Through the application of 3D spheroid culture, patient-derived gastric cancer organoids (PDOs), and an in vivo model, we confirmed the role of EHMT2 in GC cell proliferation.<h4>Results</h4>In this study, we found that EHMT2, a histone 3 lysine 9 (H3K9) methyltransferase, is significantly overexpressed in GC patients compared with healthy individuals.