Objective: To investigate whether chemically synthesized double-stranded RNA (dsRNA) targeting epidermal growth factor receptor (EGFR) could induce gene silencing in non-small-cell lung cancer (NSCLC) cells, and to assess the degree of EGFR gene silencing and its effect on functional outcome.
Methods: NSCLC cell line SPC-A-1 was transfected with target sequence-specific dsRNA formulated with Lipofectamine 2000. Fluorescent microscopy and flow cytometry were used to measure the reduction in the production of the EGFR protein. Real-time PCR was used to detect the silencing of the EGFR gene level. Colony assay was adopted to measure the cellular proliferation and colony formation. A tumor burdened athymic nude mouse model was established to calculate the tumor growth inhibition rate.
Results: The dsRNA-EGFR was shown to be effective with a 71.3% down-regulation of EGFR protein production and 50.0% of silencing of EGFR gene. The dsRNA-EGFR significantly reduced colony numbers by 66.8% in vitro and inhibited the tumor growth in vivo. The tumor growth inhibition rate was 75.0%.
Conclusion: The sequence specific dsRNA showed a blockbuster effect in downregulation of EGFR gene level and protein production, inhibition of the cellular proliferation and tumor growth.