Abstract: Objective To investigate the effect and mechanism of myosin heavy chain 11( MYH11 ) on the malignant biological behaviors of laryngeal squamous cell carcinomacells. Methods qRT-PCR was used to detect the expression level of MYH11 mRNA in laryngealsquamous cell carcinoma tissues and cells. Laryngeal squamous cell carcinoma cells TU686 were divided into 2 groups: si-MYH11 group and si-NC group. FD-LSC-1 cells were divided into 2 groups: MYH11 group and Vector group. CCK8, flow cytometry, wound-healing assay and Transwell assay were used to determine the cell proliferation, apoptosis, migration, and invasion abilities, respectively. Western blotting was used to detect the phosphorylation level of ERK1 / 2 and the expressionlevel of MAPK in each group of cells. Results MYH11 was highly expressed in laryngeal squamouscell carcinoma tissues and cells. The proliferation, migration, and invasion ability of TU686 cells inthe si-MYH11 group were significantly lower than those in the si-NC group ( P < 0. 05), and cell apoptosis was significantly higher than that in the si-NC group (P < 0. 01), the ERK1 / 2 phosphorylation level and MAPK expression level were significantly lower than those in the si-NC group (P< 0. 01). The proliferation, migration, and invasion ability of TU686 cells in the MYH11 groupwere significantly higher than those in the Vector group (P < 0. 05), and cell apoptosis was significantly lower than that in the Vector group ( P < 0. 01), the phosphorylation level of ERK1 / 2 and MAPK expression level were significantly higher than those in the Vector group (P < 0. 01). Conclusion MYH11 activates the ERK/ MAPK signaling pathway and promotes the proliferation, migration, and invasion of laryngeal squamous cell carcinoma cells.

Key words: MYH11, laryngeal squamous cell carcinoma, growth, migration