ANGPTL4 and gastric adenocarcinoma: In vitro, COL1A1 overexpression in HUVECs increased ANGPTL4, and co-culture with the gastric adenocarcinoma line MKN45 enhanced cancer cell invasion and proliferation, supporting a model in which ANGPTL4 from COL1A1+ ECs engages SDC4 on tumor cells to promote GC progression and spread.