SNAI1 and esophageal squamous cell carcinoma: CBX8 acts as an oncogene in hepatocellular carcinoma (HCC) and promotes tumor growth and metastasis via activation of AKT/β-catenin signaling21, but suppresses cell migration, invasion and metastasis in esophageal squamous cell carcinoma (ESCC) and inhibits epithelial-mesenchymal transition (EMT) by repressing SNAIL expression22.