Abstract: Objective To investigate the expression of circRNA circUGGT2 in colorectal cancer (CRC) and its effect on the proliferation, migration and invasion of CRC cells. Methods A total of 45 surgically resected CRC tissues and paracancerous tissues were collected from the Department of Gastrointestinal Surgery, Yue Bei People's Hospital between September 2018 and March 2019. The expression level of circUGGT2 in human normal colon epithelial cell line NCM460 and CRC cell lines HT29, HCT116, SW480 and SW620 was detected by qRT-PCR. The diagnostic efficacy of circUGGT2 was evaluated by plotting the receiver operating characteristic (ROC) curve and calculating the area under the curve (AUC). The si-circUGGT2 and si-NC were transfected into SW480 cells, respectively. The cell proliferation was detected by CCK-8 assay and clone formation assay. The migration and invasion ability of the cells were detected by scratch experiment and Transwell assay. Results Compared with paracancerous tissues, circUGGT2 was highly expressed in CRC tissues (P<0.001), which was related to tumor size, infiltration depth and TNM stage of patients (all P<0.05); the AUC of circUGGT2 to diagnose CRC was 0.702. The expression level of circUGGT2 in the 4 CRC cells was higher than that in NCM460 cells (all P<0.001), especially in SW480 cells. Compared with the si-NC group, the proliferation rate and scratch healing rate of SW480 cells decreased after silencing circUGGT2 (all P<0.05), and the number of clone formation, migration and invasion cells were also significantly reduced (all P<0.05). Conclusions circUGGT2 is highly expressed in CRC, and silencing circUGGT2 can inhibit the proliferation, migration and invasion of CRC cells. circUGGT2 is a potential molecular target for diagnosis and treatment of CRC.

Key words: Colorectal cancer, circRNA, circUGGT2, Proliferation, Migration, Invasion