Inhibition of lung tumor growth in nude mice by siRNA targeting on EGFR

The inhibitory effect of lung tumor growth in nude mice by siRNA targeting on EGFR （epidermal growth factor receptor） was investigated. Three different chemically synthesized small interfering RNAs (siRNAs) targeting on EGFR were utilized to block EGFR gene expression in a human non-small cell lung cancer (NSCLC) cell line A549, which overexpresses the EGFR protein. The results demonstrated that EGFR siRNAs potently suppress the expression of EGFR in A549 cells and the most efficacious siRNA is EGFR siRNA_1. Decreasing EGFR expression can notably increase the apoptosis and inhibit the proliferation of A549 cells. In the end, subcutaneous tumor models were established with luciferase expressing lung cancer cell line (A549-luc), and the tumor growth and bioluminescence were non-invasively monitored by an in vivo imaging system in real time. A quantitative analysis of the tumor luciferase gene spatial expression and tumor volume of different treatment groups showed that the growth velocity of EGFR siRNA_1 treatment group is lower than that of the Notarget siRNA treatment group, indicating that siRNA targeting EGFR can inhibit the lung subcutaneous tumor growth in nude mice.