Given that IL6 over expression is strongly correlated with malignant behavior in NSCLC, especially in lung adenocarcinoma (Additional file 1: Figure S1D), the expression of ERβ and IL6 in a normal bronchial epithelial cell line (HBE) and lung adenocarcinoma cell lines A549 and H1793 was evaluated by western blot. Here, ESR2 is linked to lung adenocarcinoma.