RNA Interference of Caveolin-1 Via Lentiviral Vector Inhibits Growth of Hypopharyngeal Squamous Cell Carcinoma FaDu Cells In Vitro and In Vivo

Objective: To investigate the effects of caveolin-1 (CAV1) on the growth of hypopharyngeal squamous cell carcinoma (HSCC) FaDu cells in vitro and in vivo. Methods: A CAV1-RNAi-lentivirus construct was transfected into FaDu cells and expression of caveolin-1 was tested by RT-PCR and western blotting analysis. Cell apoptosis was analyzed by transferase-medisated dUTP nick-end labeling (TUNEL) assay. Tumor inhibition effects were investigated by injecting rCAV1-RNAi-lentivirus construct into tumors created with FaDu cells in the HSCC mouse model, with the empty-vector lentivirus as a control. CAV1 expression in xenografts was tested by RT-PCR and immunohistochemistry. Results: RT-PCR and western blot analysis demonstrated successful construction of the CAV1-RNAi-lentivirus construct producing small hairpin RNA. The average weights and volumes of tumor in mice treated with CAV1-RNAi-lentivirus were lower than in mice with control treatment (P<0.05). RT-PCR revealed weak positive expression of CAV1 in CAV1-construct-treated xenografts and immunohistochemistry confirmed lower CAV1 expression than in controls.(P<0.05). In addition, downregulation of CAV1 increased cell apoptosis in vitro. Conclusion: The growth of HSCCs could be inhibited by recombinant CAV1-RNAi-lentivirus in vitro and in vivo.