To investigate the function of ADAMTS9 in GC cells, we firstly evaluated its expression in a panel of human GC cell lines and an immortalized human gastric epithelial cell line GES-1, finding that mRNA and protein levels of ADAMTS9 were markedly decreased in most GC cell lines compared with in GES-1 cells (Fig. 2A, B). Here, ADAMTS9 is linked to gastric cancer.