OncoTargets and Therapy (Dec 2020)
A Circular RNA Derived from Golgi Glycoprotein 1 mRNA Regulates KRAS Expression and Promotes Colorectal Cancer Progression by Targeting microRNA-622
Abstract
Shuhong Hao,1 Rongfeng Qu,1 Chunmei Hu,1 Min Wang,2 Yarong Li1 1Department of Hematology and Oncology, The Second Hospital of Jilin University, Changchun, Jilin, People’s Republic of China; 2Department of General Surgery, The Second Hospital of Jilin University, Changchun, Jilin, People’s Republic of ChinaCorrespondence: Yarong Li; Min Wang Ziqiang Street No. 265, Changchun, Jilin 130041, People’s Republic of ChinaTel +86 431 81136827; +86 431 81136427 Fax +86 431 81136827; +86 431 81136427 Email [email protected]; [email protected]: Circular RNAs (circRNAs) represent a distinct class of non-coding RNAs that have attracted substantial research attention in recent years. We identified a novel circRNA derived from golgi glycoprotein 1 mRNA (circ_GLG1), the role of which is unknown in colorectal cancer (CRC). The purpose of this study was to explore the potential roles and mechanisms of circ_GLG1 in CRC.Materials and Methods: Quantitative reverse transcriptase-polymerase chain reaction analysis was performed to quantify circ_GLG1 expression in 40 pairs of CRC tissues and adjacent normal tissues as well as CRC cell lines. DLD1 CRC cells were transfected with a small-interfering RNA against circ_GLG1, after which cell proliferation, viability, invasion, and migration were measured through cell counting kit-8 colony-formation, transwell, and wound-healing assays, respectively. Dual-luciferase reporter assays were performed to explore the binding sites among circ_GLG1, miR-622, and Kirsten rat sarcoma (KRAS) transcripts. KRAS protein expression was detected using Western blot analysis.Results: Circ_GLG1 expression was significantly higher in CRC tissues than in adjacent normal tissues. Knocking down circ_GLG1 in DLD1 cells inhibited tumor cell viability, proliferation, invasion, and migration, and these effects were reversed by co-transfecting an miR-622 inhibitor. Circ_GLG1 promoted KRAS expression at both the mRNA and protein levels by acting as an miR-622 sponge. Dual-luciferase reporter assays demonstrated that miR-622 interacted with circ_GLG1 and KRAS mRNA.Conclusion: Our study revealed the role of the circ_GLG1–miR-622–KRAS axis in CRC. Moreover, our findings provide insight into the molecular mechanism of circ_GLG1 in CRC and suggest potential new biomarkers for diagnosing this disease.Keywords: colorectal cancer, circ_GLG1, miR-622, KRAS
