AGO2 involves the malignant phenotypes and FAK/PI3K/AKT signaling pathway in hypopharyngeal-derived FaDu cells

// Yanhui Zhang 1 , Baoxin Wang 2 , Xinwei Chen 2 , Weidong Li 3 and Pin Dong 2 1 Department of Otolaryngology Head and Neck Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China 2 Department of Otolaryngology Head and Neck Surgery, Shanghai General Hospital, Shanghai, China 3 Bio-X Institutes, Key Laboratory for The Genetics of Development and Neuropsychiatric Disorders (Ministry of Education), Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China Correspondence to: Pin Dong, email: dongpin64@aliyun.com Weidong Li, email: weidongbiox@gmail.com Keywords: AGO2, hypopharyngeal cancer, cell proliferation, FAK/PI3K/AKT signaling pathway Received: November 16, 2016 Accepted: April 03, 2017 Published: May 22, 2017 ABSTRACT Argonaute 2 (AGO2) protein is usually overexpressed in various head and neck squamous cell carcinoma. However, the precise molecular mechanisms of AGO2 in hypopharyngeal cancer have not yet been clearly understood. Here we found the AGO2 expression in hypopharyngeal cancer tissues were generally higher comparing with that of the corresponding adjacent noncancerous epithelium tissues, and these were associated with the more aggressive clinicopathologic features and the poor clinical outcomes. Stable knockdown of AGO2 protein retarded cell proliferation, migration, invasion, arrested cell cycle and induced apoptosis. Meanwhile the knockdown also inhibited the FAK/PI3K/AKT signaling pathway in hypopharyngeal-derived FaDu cells. These findings suggested that AGO2 gene might act as an oncogene which contributed to the tumorigenesis and progression, and has potential values for molecular diagnosis, clinical therapies and prognosis evaluation in hypopharyngeal cancer.