APOA4 and gastric cancer: Meanwhile, we a performed binary classification using the logistic regression classifier (LR) and random forest classifier (RF) with the hub genes (APOA4, MS4A10, SLC28A1, AQP10, and APOB) of GC in the cardiac zone as the feature genes to predict whether patients have GC, and we achieved the highest AUC in patients with GC of the cardiac zone compared to the other two zones in the GSE66229 datasets (Figure S3E).