488 SNAIL TRANSFECTION INDUCES EPITHELIAL-MESENCHYMAL TRANSITION WITH PROPERTIES OF CANCER STEM-LIKE CELL IN ESOPHAGEAL SQUAMOUS CELL CANCER

Abstract Cancer stem-like cell (CSC) is an important player in tumorigenesis and tumor progression. Snail has been demonstrated as a key driver for epithelial-mesenchymal transition (EMT) that is closely linked with generation of stem-like cell in human cancer. We aim to investigate if Snail transfection induces EMT and properties of stem-like cell in esophageal squamous cell carcinoma (ESCC) cell lines. Methods A lentivirus system was used to transfect human Snail via a plasmid pLV-EF1a-hSnail-Hyg into KYSE-170 and KYSE-510 ESCC cell lines. Immunoblotting was used to determine expression of EMT associated markers including Vimentin, E-cadherin, Fibronectin and N-cadherin. Assays for cell migration and invasion were conducted in Snail-transfected cells and its vector control. Cytotoxicity (MTT) and cell proliferation assay was used to determine cell growth. Sphere formation assay and flow cytometry (FCM) were employed to characterize stem cell properties while examining expression of stemness genes by using real-time polymerase chain reaction (PCR). Results After Snail transfection, mesenchymal markers, Vimentin, N-cadherin increased, whereas epithelial marker E-cadherin decreased. Snail-transfected. ESCC cells presented a significant increase in RNA expression of stemness genes such as Nanog, Oct4, ABCG2 and Sox2 with an induction in sphere formation. Moreover, ability of cell migration and invasion increased after Snail-transfection in ESCC with increased chemoresistance to cisplatin, taxol, and 5-Fluorouracil(5-FU) and an increase in radioresistance as well. Conclusion Our results demonstrated that Snail transfection induced EMT with properties of CSC in ESCC cell lines.