Dusp6 inhibits epithelial-mesenchymal transition in endometrial adenocarcinoma via ERK signaling pathway

Background. Endometrial adenocarcinoma (EAC) is one of the most commonly diagnosed gynaecological malignancies among female population of the developed countries. DUSP6 is a negative regulator of ERK signaling, which is a molecular switch involved in MAPK signaling during the progress of malignancies. DUSP6 was previously found to inhibit tumorigenesis and EMT-associated properties in several cancers, however, its exact role in EAC remains unclear. Methods. The level of DUSP6, (E-cad) and (N-cad) in EAC cancerous tissues and respective adjacent non-cancerous tissues were examined by western-blot or immunohistochemistry. The cell growth, invasion and migration abilities were measured in Ishikawa 3H12 endometrial cancer cell lines with overexpressed or knock down DUSP6. Protein levels of EMT-associated markers E-cadherin, N-cadherin and Vimentin were also determined. The impacts of DUSP6 on ERK signaling was assessed by detection of ERK and p-ERK. Results. Down-regulation of DUSP6 was observed in EAC compared with the normal controls. The overexpression of DUSP6 significantly attenuated tumor cell growth, invasion, migration abilities and inhibited EMT-associated markers, while knock down of DUSP6 showed opposite trends. Overexpression of DUSP6 also down-regulated p-ERK and the knock down of DUSP6 inversely up-regulated p-ERK level. Conclusions. DUSP6 inhibited cell growth, invasion and migration abilities in Ishikawa 3H12 cells as well as attenuating EMT-associated properties. This tumor suppressive effect of DUSP6 in EAC is achieved by inhibiting ERK signaling pathway.