LRFN4 and gastric cancer: LRFN4 is upregulated in clinical gastric cancer cells and fibroblasts, and a high level of LRFN4 is found to be substantially linked with tumor invasive features and shorter survival rate of patients (Liu et al., 2019a), and LRFN4 overexpression is associated with higher risk of gastric cancer (Huang et al., 2021).