CXCR4 and esophageal cancer: The only study demonstrating oncogenic properties of GAS5 showed that it upregulated CXCR4 (C-X-C motif chemokine receptor 4) by competing for miR-301a, in turn activating Wnt/β-catenin and NF-κB (nuclear factor kappa B) signaling to promote proliferation, migration, and invasion in esophageal cancer [68], suggesting that GAS5 could exert opposing functions in a tissue-specific manner.