Circ-DLG 1 promotes the proliferation of esophageal squamous cell carcinoma

Jun Rong,1,* Qian Wang,2,* Yanzhou Zhang,1 Daolong Zhu,1 Handong Sun,2 Weiwei Tang,3 Rongping Wang,1 Weihong Shi,3 Xiu-feng Cao1,2 1Department of Thoracic surgery, Taikang Xianlin Drum Tower Hospital, School of Medicine, Nanjing University, 2Department of Oncology Surgery, Nanjing First Hospital, Nanjing Medical University, Nanjing, China; 3Department of Clinical Medicine, Jiangsu Vocational College of Medicine, Yancheng, China *These authors contributed equally to this work Background: Circular RNAs (circRNAs) are a class of noncoding RNAs with closed loop structures. There has been growing evidence showing that circRNAs are involved in the pathogenesis of human diseases including various carcinomas. Our study is aimed to investigate the association between a new circRNA named circ-DLG1 (hsa_circ_0007203) and esophageal squamous cell carcinoma (ESCC) carcinogenesis. Methods: The circ-DLG1 expression levels were detected by real-time quantitative reverse transcription-polymerase chain reaction in cells, tissues, and plasmas. The correlation between circ-DLG1 expression and clinicopathologic features was then analyzed. The effect of circ-DLG1 expression on cell proliferation was evaluated in vitro by CCK8 assay and clone formation experiment. Finally, a network of circ-DLG1 with its targeted miRNA interactions and corresponding mRNAs was constructed. Results: circ-DLG1was found to be significantly upregulated in ESCC cells, tissues, and plasmas compared to normal cases. Furthermore, in vitro assays, TE10 and KYSE180, of the ESCC cell lines demonstrated that knockdown of circ-DLG1 reduced cell proliferation significantly. Prediction and annotation revealed that circ-DLG1 was able to sponge to 20 miRNAs and 60 corresponding target mRNAs. Conclusion: Our study indicated that upregulation of circ-DLG1 promoted esophageal cell proliferation ability and might serve as a novel biomarker for ESCC. Keywords: ESCC, spong, upregulation, biomarker, miRN