The role of PRRX1 in esophageal cancer.

e16046 Background: Recently, paired related homeobox 1 (PRRX1) was identified as a new EMT inducer that induces EMT in solid tumor. Interestingly, the functions of PRRX1 are significantly different, high expression of PRRX1 predicts less metastasis of breast cancer and a better prognosis. However, we observed the opposite relationship in gastric cancer, which was also reported in colorectal cancer and pancreatic cancer. While the function of PRRX1 in oesophageal cancer and whether PRRX1 induces EMT in oesophageal cancer metastasis have not been determined. Methods: One hundred primary oesophageal cancer tissue specimens were collected, immunohistochemical staining was performed to detect the expression of PRRX1. Cell proliferation, the migration and invasion were detected with different PRRX1 expression in oesophageal cancer cells. And the relationship between PRRX1 and Wnt/β-catenin pathway was also explained. Results: Regulation of PRRX1 expression might exert obvious effects on cell proliferation, especially the migration and invasion of oesophageal cancer cells. Moreover, silencing PRRX1 expression using a short hairpin RNA (shRNA) produced the opposite effects. In addition, when PRRX1 was overexpressed, inhibition of the Wnt/β-catenin pathway with XAV939 negated the effect of PRRX1 on EMT, whereas when PRRX1 was downregulated, activation of the Wnt/β-catenin pathway with LiCl impaired the effect on EMT. Conclusions: PRRX1 is expressed at high levels in oesophageal cancer specimens and is closely related to tumour metastasis in patients with oesophageal cancer. Additionally, PRRX1 induces EMT in oesophageal cancer metastasis through activation of Wnt/β-catenin signalling.