MicroRNA-188-5p targeting Forkhead Box L1 promotes colorectal cancer progression via activating Wnt/β-catenin signaling

Objective: MicroRNA-188-5p (miR-188) enhances oncologic progression in various human malignancies. Thisstudy aimed to explore its role in colorectal cancer (CRC). Materials and Methods: Human CRC tissues paired withnormal tissues, and several CRC cell lines were utilized. Real-time quantitative PCR was applied to measure theexpression of miR-188. Overexpression and knockdown were used to access the function of miR-188 and toinvestigate whether FOXL1/Wnt signaling mediates such function. The proliferation, migration and invasion of cancercells were evaluated by CCK8, wound-healing and transwell assays, respectively. Whether FOXL1 acted as a directtarget of miR-188 was verified by dual-luciferase reporter assays. Results: Levels of miR-188 were upregulated in CRCtissues than in paired-normal tissues, as well as in various CRC cell lines. High expression of miR-188 was stronglyassociated with advanced tumor stage, accompanied with significant tumor cell proliferation, invasion and migration.It was confirmed that FOXL1 played positive crosstalk between miR-188 regulation and downstream Wnt/β-cateninsignaling activation. Conclusions: All findings indicate that miR-188 promotes CRC cell proliferation and invasionthrough targeting FOXL1/Wnt signaling and could be served as a potential therapeutic target for human CRC in thefuture.