ObjectiveTo investigate the effects of Twist gene silenced by RNAi interference on proliferation, invasiveness and methylation of Ecadherin in laryngeal squamous cell carcinoma Hep2 cells.MethodsHuman laryngeal squamous cell carcinoma Hep2 cell lines were cultured, and then transfected with siRNATwist (siRNATwist group), positive control siRNAGAPDH (positive control group) and negative control missense chain (negative control group). The expressions of Twist and Ecad genes in cells of all 3 groups were detected by realtime fluorescence quantitative PCR. The expressions of Twist and Ecad proteins were detected by Western blot. MTT assay and transwell chamber were adopted to examine cell proliferations, cell migration and invasion respectively. The expression of methylation of Ecad was detected by methylationspecific polymerase chain reaction (MSP).ResultsThe expressions of Twist mRNA and proteins in siRNATwist group were lower than those in the positive control group and negative control group respectively, and the differences were all statistically significant (all P<0.05). The expressions of Ecad mRNA and proteins in siRNATwist group were higher than those in the positive and negative control groups respectively, the differences were all statistically significant (all P<0.05).The cell proliferation in siRNATwist group was significantly reduced after transfected 48 h~96 h, the difference was statistically significant (P<0.05). The migration cells and invasion cells in siRNATwist group were lower than those in the positive and negative control groups, the differences were statistically significant (all P<0.05). MSP test results showed that the amplified bands of Ecad methylation in the siRNATwist group were weakly positive, its expression intensity was significantly lower than those of the positive and negative control groups, while the unmethylation amplified bands were positive.ConclusionsSpecific inhibition of Twist gene might upregulate Ecad expression via influencing the methylation of Ecad, thereby inhibit cell proliferation and invasion. It is expected to provide new target for gene therapy of laryngeal squamous cell carcinoma.