CXCR4 and neoplasm: The CXCL12/CXCR4 axis can activate the MEK/ERK, PI3K/AKT, and Wnt/β-catenin pathways to promote EMT, thereby promoting tumor invasion and metastasis (Guo et al., 2016; Zhou et al., 2019; Mortezaee, 2020).