Abstract
This study is aimed at investigating the roles of Toll-like receptor 4 (TLR4) and microRNA-7 (miR-7) in colorectal cancer (CRC) development and progression. We assessed TLR4 and miR-7 expression in CRC cells and tissues using reverse transcription-quantitative polymerase chain reaction. The relationship between miR-7 and TLR4 was analyzed through dual luciferase reporter assays. MTT, wound healing, and cell invasion assays were conducted to examine the effects of TLR4 and miR-7 on CRC cell proliferation, migration, and invasion. Western blotting was used to explore the involvement of the TRAF6/NF-κB signaling pathway. miR-7 was underexpressed in CRC, while TLR4 levels were increased. miR-7 negatively regulated TLR4 expression and its knockdown enhanced CRC cell proliferation, migration, and invasion. TLR4 knockdown had the opposite effects. The TRAF6/NF-κB pathway was linked to TLR4's role in tumor progression. miR-7 might inhibit TRAF6/NF-κB target a signaling pathway of TLR4 and promote CRC occurrence. miR-7 may therefore be used as a sensitive biomarker in CRC patients.