Circular RNA ITCH has inhibitory effect on ESCC by suppressing the Wnt/β-catenin pathway

Abstract

// Fang Li 1,* , Liyuan Zhang 2,* , Wei Li 1 , Jieqiong Deng 1 , Jian Zheng 1 , Mingxing An 1 , Jiachun Lu 3 and Yifeng Zhou 1 1 Department of Genetics, Medical College of Soochow University, Suzhou, China 2 Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, China 3 The Institute for Chemical Carcinogenesis, The State Key Lab of Respiratory Disease, Guangzhou Medical University, Guangzhou, China * These authors contributed equally to this work Correspondence to: Yifeng Zhou, email: // Keywords : Cir-ITCH, ESCC, Wnt/β-catenin pathway Received : December 01, 2014 Accepted : January 20, 2015 Published : February 28, 2015 Abstract Circular RNAs with exonic sequences represent a special form of non-coding RNAs, discovered by analyzing a handful of transcribed genes. It has been observed that circular RNAs function as microRNA sponges. In the present study, we investigated whether the expression of circular RNAs is altered during the development of esophageal squamous cell carcinoma (ESCC). Using a TaqMan-based reverse transcriptase polymerase chain reaction assay, the relationship between cir-ITCH and ESCC was analyzed in a total of 684 ESCC and paired adjacent non-tumor tissue samples from eastern and southern China. We found that cir-ITCH expression was usually low in ESCC compared to the peritumoral tissue. The functional relevance of cir-ITCH was further examined by biochemical assays. As sponge of miR-7, miR-17, and miR-214, cir-ITCH might increase the level of ITCH . ITCH hyper expression promotes ubiquitination and degradation of phosphorylated Dvl2, thereby inhibiting the Wnt/β-catenin pathway. These results indicate that cir-ITCH may have an inhibitory effect on ESCC by regulating the Wnt pathway.