title: miR-18a downregulates DICER1 and promotes proliferation and metastasis of nasopharyngeal carcinoma.
abstract: Nasopharyngeal carcinoma, common in Southeast Asia and the southern provinces of China, often has metastasized by the time of diagnosis; thus there exists the need for improved diagnosis and treatment. Accumulating evidence indicates that microRNAs (miRNAs), which post-transcriptionally regulate protein expression, contribute to the processes of tumorigenesis, including metastasis and cellular invasion. Here, we studied the effect of one miRNA, miR-18a-which is believed to target the miRNA-processing enzyme DICERl-on nasopharyngeal carcinoma. In situ hybridization revealed that miR-18a was more highly expressed in nasopharyngeal carcinoma tissues than in control tissues (P < 0.05), and the overexpression correlated with clinical stage and lymph node metastasis (P < 0.05), but not with age and gender (P > 0.05). In vitro analysis of HK1 nasopharyngeal carcinoma cells transfected with miR-18a exhibited significantly decreased expression of DICER1 mRNA and protein but significantly increased proliferation and invasion properties compared to control cells (P < 0.05). Finally, nude mice injected with miR-18a transfected-HK1 cells displayed significantly increased tumor growth and lung metastasis in vivo (P < 0.05). These findings suggest that miR-18a expression can promote proliferation and metastasis of nasopharyngeal carcinoma cells and that these activities may occur through its regulation of DICER1.
authors: Department of Otorhinolaryngology, The First Affiliated Hospital, Nanjing Medical University Nanjing, China.
authors: Xi
authors: X
authors: Chen
authors: Department of Otorhinolaryngology, The Affiliated Jiangning Hospital of Nanjing Medical University Nanjing, China.
authors: Juan
authors: J
authors: Wang
authors: Department of Otorhinolaryngology, The First Affiliated Hospital, Nanjing Medical University Nanjing, China.
authors: Lei
authors: L
authors: Cheng
authors: Department of Otorhinolaryngology, The First Affiliated Hospital, Nanjing Medical University Nanjing, China.
authors: Mei-Ping
authors: MP
authors: Lu
keywords: Dicer1; HK1 cells; Nasopharyngeal carcinoma; metastasis; microRNA-18a; proliferation