CD44 and neoplasm: Among ten CD44 variants, CD44v9 has been closely associated with cellular processes and tumorigenicity comprising cell proliferation, metastasis, and tumor invasiveness through epithelial-mesenchymal transition (EMT) (Yasui et al., 1998; Miwa et al., 2017; Vaquero et al., 2017; Taniguchi et al., 2018).