Oroxylin a could be a Promising Radiosensitizer for Esophageal Squamous Cell Carcinoma by Inducing G2/M Arrest and Activating Apoptosis

To evaluate the radiosensitization of Oroxylin A on esophageal carcinoma cell as well as the optimal scheduling of Oroxylin A and radiotherapy (RT). Cell proliferation was estimated by a CCK8 assay. Radiosensitization was evaluated by a clonogenic survival assay. The progressions of Cell apoptosis and Cell cycle were investigated by flow cytometry. Expressions of survivin and cell cycle regulators were evaluated by Western blot analysis. A dose-dependent cell survival reduction was found in response to radiation with or without Oroxylin A. The apoptosis rates were remarkably dose-dependent higher in combination groups than in either Oroxylin A or radiation alone group. Besides, Oroxylin A could obviously radiosensitize ESCC cells by arresting tumor cells in G2/M phase and regulating cyclin B1 and Cdc 2 protein expression. Oroxylin A could be a promising radiosensitizer for esophageal squamous cell carcinoma by inducing G2/M phase blocking and activating cell apoptosis.