CD44 has been reported to be involved in the regulation of diverse molecules and pathways, such as EMT-related molecules, MMPs [39], cycle-related proteins [40], glycolysis-related genes [41], Wnt/β-catenin pathway [40], and PI3K-Akt pathway [42], which modulated the proliferation, metastasis, and therapy-resistance of cancer cells. The gene discussed is CD44; the disease is cancer.