Abstract: Objective To investigate the effect of total flavonoids from Selaginella uncinata (TFS) on the proliferation, migration and invasion of laryngeal squamous cell carcinoma TU177 cells and its possible mechanism. Methods TU177 cells were cultured in vitro and were divided into control group, TFS-5 μg / mL, - 15 μg / mL, - 25 μg / mL groups, miR-3662 group, miR-NC group, 25 μg / mL TFS + anti-miR-3662 group and 25 μg / mL TFS + anti-miR-NC group. CCK-8 method and colony formation assay were used to detect cell proliferation. Scratch assay was used to detect cell migration. Transwell assay was used to detect cell invasion. Western blotting was used to detect the protein expression levels of epithelial cadherin (E-Cadherin) and neural cadherin (N-Cadherin) in cells, and RT-qPCR method was used to detect the expression level of miR-3662. Results Compared with the control group, the cell inhibition rate of TFS groups was increased (P< 0. 05), but the number of colonies, the wound healing rate and the number of invasions, and the expression level of N-Cadherin protein were decreased (P < 0. 05), while the expression levels of E-Cadherin protein and miR-3662 were increased (P < 0. 05), all in a dose pendent manner. The expression level of miR-3662 in the laryngeal squamous cell carcinoma tissues was significantly lower than that in the adjacent tissues (P < 0. 05). Compared with the miR-NC group, the cell inhibition rate and the expression level of E-Cadherin protein in the miR-3662 group were increased (P< 0. 05), but the number of colonies, the wound healing rate and the number of invasions, and the expression level of N-Cadherin protein were decreased (P<0. 05). Compared with the 25 μg / mL TFS + anti-miR-NC group, the cell inhibition rate and the expression level of E-Cadherin protein in the 25 μg / mL TFS + anti-miR-3662 group were decreased (P<0. 05), but the number of colonies, the wound healing rate and the number of invasions, and the expression level of N-Cadherin protein were increased (P<0. 05). Conclusion Total flavonoids from Selaginella uncinata could inhibit the proliferation, migration and invasion of laryngeal squamous cell carcinoma TU177 cells, and its mechanism may be related to the up-regulation of miR-3662 expression in the cells.

Key words: total flavonoids from Selaginella uncinata, laryngeal squamous cell carcinoma, miR-3662, cell proliferation, migration, invasion