More importantly, unlike that in PURA-expressing cell lines, there was no change in the invasive and metastatic potential upon overexpression of MEST in PURA-deficient ESCC cells, and the promoting effects of MEST in cancer invasion and metastasis could be restored by re-overexpression of PURA (Fig. 4j and k). The gene discussed is PURA; the disease is esophageal squamous cell carcinoma.