The radiosensitizing effect of Paeonol on lung adenocarcinoma by augmentation of radiation-induced apoptosis and inhibition of the PI3K/Akt pathway

AbstractPurpose: To investigate the radiosensitizing effect and mechanism of action by the natural product Paeonol on lung adenocarcinoma both in vitro and in vivo.Materials and methods: Two lung adenocarcinoma cell lines (human lung adenocarcinoma cell line A549 and mouse Lewis lung carcinoma (LLC) cell line) were chosen for this research. In order to select the experimental concentrations of Paeonol, cytotoxicity was determined using a MTT (3-[4,5-dimethylthiazol-2-yl]-2,5- diphenyltetrazolium bromide) assay. A clonogenic assay was performed to measure the radiosensitizing effects. Apoptosis was determined by the Tunel (terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling) assay and flow cytometry. Protein expression was analyzed by Western blotting. To test the radiosensitizing effect in vivo, a transplanted tumor model was established.Results: The MTT assay showed that Paeonol inhibited proliferation of cells. Paeonol concentration ranged from an IC5 (5% inhibiting concentration) to a...