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 cellcarcinoma (HSCC) FaDu cells in vitro and in vivo. Methods: A CAV1-RNAi-lentivirus construct was transfectedinto FaDu cells and expression of caveolin-1 was tested by RT-PCR and western blotting analysis. Cell apoptosiswas analyzed by transferase-medisated dUTP nick-end labeling (TUNEL) assay. Tumor inhibition effects wereinvestigated by injecting rCAV1-RNAi-lentivirus construct into tumors created with FaDu cells in the HSCCmouse model, with the empty-vector lentivirus as a control. CAV1 expression in xenografts was tested by RT-PCRand immunohistochemistry. Results: RT-PCR and western blot analysis demonstrated successful construction ofthe CAV1-RNAi-lentivirus construct producing small hairpin RNA. The average weights and volumes of tumorin mice treated with CAV1-RNAi-lentivirus were lower than in mice with control treatment (P<0.05). RT-PCRrevealed weak positive expression of CAV1 in CAV1-construct–treated xenografts and immunohistochemistryconfirmed lower CAV1 expression than in controls.(P<0.05). In addition, downregulation of CAV1 increased cellapoptosis in vitro. Conclusion: The growth of HSCCs could be inhibited by recombinant CAV1-RNAi-lentivirusin vitro and in vivo.