Ginsenoside Rg3 promotes the antitumor activity of gefitinib in lung cancer cell lines.

Lung cancer is one of the most common types of cancer with one of the highest incidence and mortality rates. Gefitinib is widely used for the treatment of non-small cell lung cancer (NSCLC). However, issues regarding drug resistance, toxicity and limited applicability have been associated with gefitinib. The aim of the present study was to investigate whether ginsenoside Rg3 enhances the anticancer activity of gefitinib in NSCLC cells. MTT assay demonstrated that ginsenoside Rg3 increased the cytotoxic effect of gefitinib in NSCLC cell lines in a dose- and time-dependent manner. In addition, flow cytometric analysis revealed that the combined treatment with gefitinib and ginsenoside Rg3 significantly increased apoptosis in NSCLC cell lines. Transwell migration assays demonstrated that the combined treatment with gefitinib and ginsenoside Rg3 significantly decreased NSCLC cell migration compared with gefitinib or ginsenoside Rg3 treatment alone. Furthermore, western blot analysis revealed that in NSCLC cell lines, the combined treatment with gefitinib and ginsenoside Rg3 increased protein expression levels of pro-apoptotic proteins Bax and cleaved-caspase-3, whilst the expression level of anti-apoptotic protein Bcl-2 decreased. In addition, western blot analysis revealed that, in NSCLC cell lines, the combined treatment with gefitinib and ginsenoside Rg3 decreased the protein expression levels of pro-migration factors SNAIL and SLUG, whilst the expression level of anti-migration protein E-cadherin increased. In conclusion, ginsenoside Rg3 may be able to enhance the anticancer activity of gefitinib, making NSCLC cells more sensitive to gefitinib.