To explore the biological role of PCSK9 in GC, we applied seven human GC cell lines (SGC-7901, MKN-45, MKN-28, KATO-III, AGS, MGC-803, and NCI-N87) and a normal gastric mucosa cell line (GES-1) to the in vivo study. This evidence concerns the gene PCSK9 and gastric cancer.