Abstract: Objective · To explore the effects of adenovirus vector-mediated small interfering RNA (siRNA) targeting phosphatase nuclear targeting subunit
(PNUTS) on proliferation, invasion, migration and epithelial-mesenchymal transition (EMT) of laryngeal squamous cell carcinomas Hep-2 cells and its
mechanism. Methods · Recombinant adenovirus vector expressing PNUTS siRNA was infected into laryngeal squamous cell carcinomas Hep-2 cells and the
experiment was designed into PBS group, Ad-GFP group and Ad-siPNUTS group. Levels of PNUTS mRNA and protein were detected by real-time PCR and
Western blotting respectively. MTT assay was used to detect proliferation abilities of Hep-2 cells. Transwell assays were used to detect invasion and migration abilities of Hep-2 cells. The expression levels of total Rb, phosphorylated Rb (p-Rb), PI3K, phosphorylated AKT (p-AKT), E2F1, E-cadherin, N-cadherin and ZEB1 protein were detected by Western blotting. Results · Compared with Ad-GFP group, in Ad-siPNUTS group, the PNUTS mRNA and protein (both P=0.000) levels were dramatically decreased. The proliferation of Ad-siPNUTS infected Hep-2 cells were inhibited on the second day (P=0.004), the third day (P=0.001) and the fourth day (P=0.000). Meanwhile, the invasion and migration abilities of Ad-siPNUTS infected Hep-2 cells were decreased (both P=0.000). The expression levels of total Rb (P=0.000), p-Rb (P=0.000), PI3K (P=0.023), p-AKT (P=0.000), E2F1 (P=0.000), N-cadherin (P=0.005) and ZEB1 (P=0.000) were decreased while the E-cadherin (P=0.003) was increased. Conclusion · Ad-siPNUTS could inhibit the proliferation, invasion and migration abilities of Hep-2 cells and reverse the development of EMT, which may be related to PI3K/AKT signaling pathway and Rb signaling pathway.

Key words: laryngeal squamous cell carcinomas, phosphatase nuclear targeting subunit, phosphorylated Rb, invasion, epithelial-mesenchymal transition