Abstract: Objective To investigate whether long intergenic non-coding RNA 00659 (LINC00659) targets miR-149-5p to regulate the proliferation, migration, invasion and radiosensitivity of esophageal squamous cell carcinoma Eca-109 cells. Methods The expression of LINC00659 and miR-149-5p in 30 pairs of esophageal squamous cell carcinoma tissues and control tissues was analyzed using real-time quantitative PCR (RT-qPCR). Eca-109 cells cultured in vitro were divided into si-NC group, si-LINC00659 group, miR-NC group, miR-149-5p group, siLINC00659 + anti-miR-NC group, and si-LINC00659 + anti-miR-149-5p group. The effects of LINC00659 and miR-149-5p on the proliferation of Eca-109 cells were measured by CCK-8 cell viability assay. The effects of LINC00659 and miR-149-5p on the migration and invasion of Eca-109 cells were determined through Transwell migration / invasion assay. The colony formation test was used to measure the survival fraction and radiosensitization ratio of Eca-109 cells. The relationship between LINC00659 and miR-149-5p was verified by dual luciferase report experiment. Results The expression level of LINC00659 was significantly higher in the esophageal squamous cell carcinoma tissue than in the control group, while the expression level of miR-149-5p was significantly lower in the esophageal squamous cell carcinoma tissue than in control tissues (P< 0. 05). Compared with the si-NC group, the proliferation inhibition rate of Eca-109 cells in the si-LINC00659 group was increased, and the number of migratory / invasive cells and the cell survival fraction were decreased (P< 0. 05). The radiosensitization ratio of Eca-109 cells in the si-LINC00659 group was 1. 938. In the miR-149-5p group relative to the miR-NC group, the proliferation inhibition rate of Eca-109 cells was increased, and the number of migratory / invasive cells and the cell survival fraction were decreased (P< 0. 05). The radiosensitization ratio of Eca-109 cells in the miR-149-5p group was 1. 545. miR-149-5p was the target gene of LINC00659. Compared with the si-LINC00659 + anti-miRNC group, the proliferation inhibition rate of Eca-109 cells in si-LINC00659 + anti-miR-149-5p group was decreased, and the number of migratory / invasive cells and the cell survival fraction were increased (P < 0. 05). The radiosensitization ratio of Eca-109 cells in si-LINC00659 + anti-miR149-5p group was 0. 657. Conclusion The interference of LINC00659 inhibits cell proliferation, migration and invasion, improves cell radiosensitivity of esophageal squamous cell carcinoma Eca109 cells by up-regulating miR-149-5p.

Key words: LINC00659, esophageal squamous cell carcinoma cancer, proliferation, migration, invasion, radiosensitivity, miR-149-5p