PRRX1 and esophageal squamous cell carcinoma: Some established oncogenes are also direct targets of miR-655 in other types of cancers, such as Prrx1 in breast cancer (35), ZEB1 and TGFBR2 in ESCC (36), ADAM10 in hepatocellular carcinoma (31), and PAX6 in retinoblastoma (30).