To explore the role of CHI3L1 in cancer cell invasion and adhesion, gastric cancer cells (MKN-45 and AGS) or breast cancer cells (MDA-MB-231, MDA-MB-435, and MDA-MB-468) were cultured in media containing the recombinant CHI3L1 protein and were subsequently subjected to invasion and adhesion assays. The gene discussed is CHI3L1; the disease is breast cancer.