Abstract:

Objective To investigate the ability of Epstein-Barr virus（EBV） microRNA Bart 6-5p to regulate Dicer expression and thereby influence the epithelial-mesenchymal transition（EMT） in nasopharyngeal carcinoma cells. Methods Expression of microRNA Bart6-5p and Dicer were quantitated using real-time quantitative PCR in the EBV-positive nasopharyngeal carcinoma cell line C666-1 and lymphoma cell lines Akata，Daudi，Raji and Namalwa. In C666-1 cells with the highest EBV load，microRNA Bart6-5p expression was inhibited and subsequent changes in levels of EMT-related molecular markers were examined. Results Bart6-5p expression followed the trend C666-1>Akata>Daudi>Raji>Namalwa，while Dicer followed the inverse trend. Inhibiting Bart6-5p expression in C666-1 increased expression of Dicer and the positive EMT marker E-cadherin，while it decreased expression of the negative EMT markers vimentin，ZEB1 and ZEB2. Conclusion EBV microRNA Bart6-5p can influence the EMT in nasopharyngeal carcinoma by regulating Dicer expression.

Key words: Nasopharyngeal neoplasm, microRNA, Epstein-Barr virus, Eepithelial mesenchymal transition