Effects of combining erlotinib and RNA-interfered downregulation of focal adhesion kinase expression on gastric cancer

OBJECTIVE: To investigate the synergistic effects of combining erlotinib and RNA-interference downregulation of focal adhesion kinase (FAK) expression on the proliferation, apoptosis, invasion and migration of the human gastric adenocarcinoma cell line AGS. METHODS: Cells were divided into five experimental groups: Group A, nontransfected control; Group B, transfected with empty vector; Group C, transfected with FAK-shRNA; Group D, erlotinib treatment; Group E, combination erlotinib treatment and transfected with FAK-shRNA. FAK protein levels were confirmed via Western blotting. Cell proliferation (CCK-8 assay, apoptosis (flow cytometry), cell invasion (transwell assay) and migration (scratch assay) were evaluated. RESULTS: RNA interference significantly decreased FAK protein levels. Cell proliferation, invasion and migration were significantly lower in Groups C, D and E compared with Group A, and significantly lower in Group E than in Groups C and D. CONCLUSIONS: RNA interference effectively silences FAK expression and inhibits malignant cell proliferation and invasion in gastric cancer cells. The effect of FAK inhibition is increased by co-treatment with erlotinib.