Inhibitory Effects of Scutellarein on Proliferation of Human Lung Cancer A549 Cells through ERK and NFκB Mediated by the EGFR Pathway

High expression levels of cyclooxygenase-2 (COX-2) contribute a strong proliferative ability to human lung cancer cells, and this function is link to the epidermal growth factor receptor (EGFR) pathway, which was mediated by extracellular-signal-regulated kinase (ERK) and nuclear factor kappa B (NF kappa B). In this study, scutellarein, a flavonoid compound, was screened for proliferation inhibition at different concentrations (0, 5, 25 and 50 mu M) at 24 h or 48 h in human lung cancer cell line A549. Results showed that A549 cell proliferation was inhibited by 50 mu M scutellarein treatment in 24 h and 48 h of treatment. The expression levels of phosphorylated EGFR, phosphorylated ERK, phosphorylated NF kappa B and COX-2 were reduced in a dose-dependent manner after 24 h scutellarein treatments at different concentrations. Further, ERK inhibitor U0126 and NF kappa B inhibitor MG132 also inhibited A549 cell proliferation similar to 50 mu M scutellarein treatment from 24 h to 48 h. The experimental results showed that scutellarein could inhibit proliferation of the human lung cancer cell line A549 through ERK and NF-kappa B mediated by the EGFR pathway.