To investigate whether IL–20 is involved in prostate tumor metastasis through EMT, RT-qPCR was used to analyze the expression of the epithelial marker E-cadherin, N-cadherin, STAT3, vimentin, and the mesenchymal marker fibronectin in PC–3 cells incubated with IL–20. The gene discussed is CDH1; the disease is prostate neoplasm.