Increased circular RNA UBAP2 acts as a sponge of miR-143 to promote osteosarcoma progression

// Hao Zhang 1, * , Guangchao Wang 1, * , Chen Ding 1, * , Peng Liu 2, * , Renkai Wang 1 , Wenbin Ding 1 , Dake Tong 1 , Dajiang Wu 1 , Cheng Li 1 , Qiang Wei 1 , Xin Zhang 1 , Di Li 1 , Peizhao Liu 1 , Haochen Cui 1 , Hao Tang 1 and Fang Ji 1 1 Department of Orthopedics, Changhai Hospital, Second Military Medical University, Shanghai, China 2 Department of General Sugery, Changhai Hospital, Second Military Medical University, Shanghai, China * These authors have contributed equally to this work Correspondence to: Fang Ji, email: doctorjif@126.com Hao Tang, email: tanghao1978@163.com Keywords: circRNA, circUBAP2, osteosarcoma, miR-143, Bcl-2 Received: March 24, 2017      Accepted: May 23, 2017      Published: June 27, 2017 ABSTRACT Deregulated expression of circular RNA (circRNA) has been determined to be important in carcinogenesis and progression; however, in the most common type of primary malignant bone tumor osteosarcoma, the roles of circRNA in cancer development still remain to be elucidated. Here, we found that circRNA UBAP2 (circUBAP2) expression is significantly increased in human osteosarcoma tissues as compared to those in matched controls. Increased circUBAP2 expression was significantly correlated with human osteosarcoma progression and prognosis. Furthermore, increased circUBAP2 could promote osteosarcoma growth and inhibit apoptosis both in vitro and in vivo . Mechanistically, circUBAP2 was found to inhibit the expression of microRNA-143 (miR-143), thus enhancing the expression and function of anti-apoptotic Bcl-2, which is a direct target of miR-143. Together, our results suggest the roles of circUBAP2 in osteosarcoma development and implicate its potential in prognosis prediction and cancer therapy.