It has been found that the absorption of exosomal GKN1 by stomach epithelium may inhibit the proliferation of GC cells, potentially representing a crucial self‐protective mechanism of the body in response to GC.[57] As demonstrated by Guo et al., this protein is expressed at low levels in tumors but is highly expressed in adjacent normal tissue.[58] Specifically, the concentrations of serum GKN1 in 100 HDs and 150 patients with GC were significantly different, at 6.35 ± 0.82 ng mL−1 and 3.50 ± 0.57 ng mL−1, respectively (p < 0.0001). This evidence concerns the gene GKN1 and gastric cancer.