UBE2I and metastatic prostate carcinoma: In addition, our findings of the direct correlation between Flot-1 sumoylation and abnormal up-regulation of Snail provide potential implications that Flot-1 sumoylation may serve as a marker for diagnosis of malignant prostate cancer, and a novel therapeutic strategy to control EMT in metastatic prostate cancer by targeting the E2 conjugating enzyme UBC9.