Down-regulation of miRNA-204 by LMP-1 enhances CDC42 activity and facilitates invasion of EBV-associated nasopharyngeal carcinoma cells

•We found that miRNA-204 is down-regulated in NPC cell lines and patient tissues.•LMP-1 down-regulates miR-204 expression through activation of Stat-3.•Cell division cycle 42 protein (cdc42) is a direct target of miRNA-204.•miR-204 inhibits cell invasion and metastasis partly through targeting cdc42. Nasopharayngeal carcinoma (NPC) is an Epstein–Barr virus (EBV)-associated malignancy. It is known that microRNAs are implicated in the progression of NPC. However, the role of miR-204 in NPC is poorly understood. In this study, we found that miR-204 was down-regulated in NPC cells and tissues. Low-level expression of miR-204 was significantly associated with a more aggressive and poor prognostic phenotype of NPC. We further found that EBV-encoded latent membrane protein 1 (LMP-1) suppressed miR-204 expression by activating Stat-3. Cdc42 was identified as a direct target of miR-204. Mir-204 inhibited EBV positive C666-1 cell invasion and metastasis partly through targeting cdc42.