Rab1A knockdown inhibits metastasis and enhances radiosensitivity in NPC cells in vitro. (A) The expression of Rab1A, S6K1 and P-S6K1 proteins in 9 NPC cell lines and one human nasopharyngeal normal epithelium cell line NP69 is detected by western blotting. (B) Immunoblot analysis of Rab1A expression in 6-10B and S-26 cells transfected with Rab1A overexpression vector or 5-8F and CNE2 cells transfected with Rab1A shRNA. GAPDH served as a loading control. (C and D) The migration ability of 5-8F and CNE2 cells with Rab1A knockdown was evaluated by transwell assays. The left panels show representative images of cells that migrated through the PET membrane (magnification 200X). The right panel shows histograms of the data. Results are expressed as mean ± SD of three independent experiments. (E) Representative photos of 5-8F cells stably expressing Rab1A shRNA or a control shRNA cultured for 2 weeks after exposure to irradiation doses of 0, 2, 4, 6, 8 Gy, respectively. (F) Doses survival curve of 5-8F cells was constructed using the linear quadratic model. (G) Representative images of CNE2 cells transfected by Rab1A shRNA or scrambled shRNA (NC) cultured for 14 days after irradiation with the indicated Gy dose. (H) Doses survival curve of CNE2 cells was plotted using the linear quadratic model. Error bars: mean ± SD. **P < 0.01, NS, no significant.