Firstly, green tea catechins, predominantly EGCg, have potent antioxidant activity and may reduce adverse events associated with pro‑oxidant anticancer agents. Generally, anthracyclins and a platinum agent (cisplatin) are considered to release ROS and cause unique side effects, namely, cardiac toxicity and renal dysfunction, respectively. Green tea catechins have been shown to protect against normal cell damage from ROS. Previously, it was demonstrated that daily intake of green tea tablets containing 474 mg catechins significantly reduced the oxidative stress induced by hepatic arterial infusion of cisplatin and 5‑fluorouracil in patients with metastatic liver cancer or hepatocellular carcinoma (1). It has also been indicated that administration of EGCg together with pro‑oxidant anticancer agents is useful in minimizing adverse effects (20,21). In Japan, cisplatin combination regimens have been considered as standard chemotherapy for non-small cell lung cancer (NSCLC) (22). We hypothesized that conventional chemotherapy combined with green tea catechins may be useful for enhancing their anticancer effectiveness and reducing their adverse drug reactions. Therefore the A549 cell line, which is derived from NSCLC, was adopted in this study assuming lung cancer therapy.