CXCR4 and colorectal cancer: In 2014, T. Yu et al. [24] found that suppressing expression of CXCR4 by MicroRNA-9 could inhibit the proliferation of oral squamous cell carcinoma cells both in vitro and in vivo through the Wnt/β-catenin signaling pathway, and activation of CXCR4 expression led to the constitutive activation of β-catenin, implying the important role of Wnt/β-catenin in CXCR4 signaling, which was consistent with the previous reports in colorectal cancer [25], ovarian cancer [26], pancreatic cancer [23], and bone marrow stromal cells [27].