Pronounced Enhancement in Radiosensitization of Esophagus Cancer Cultivated in Docosahexaenoic Acid Via The PPAR-γ Activation

Background: Docosahexaenoic acid (DHA) has been reported to slow the tumor growth and improve prognosis, and been used to co-operate with many other chemotherapy medicines. Up to now, survey focuses on the interaction between DHA and radiation is relatively modest. Our study sought to evaluate the changes of radiosensitivity caused by DHA on esophageal cancer cells. Besides, potential mechanism and molecular are needed to be explored. Results: ： DHA enhanced proliferation inhibition of irradiation on esophageal cancer cells. DNA damage, especially double-strand break, induced by irradiation, was sharply increased by DHA addition. DHA accelerated G2/M phase blocking, cell apoptosis and lipid peroxidation after radiotherapy. The similar outcomings were observed in mouse xenograft tumor experiment that the malignancy substantially dismissed after the combined treatment of DHA and irradiation. Moreover, PPAR -γ was verified to increase post-treatment. Suppression of PPAR -γ would attenuate the radio sensitization triggered by DHA incompletely. Conclusion: ： DHA could improve radio sensitivity in esophageal squamous cancer cells in vivo and in vitro by activating PPAR -γ. Due to its explicitly usage and convenient, DHA and other PPAR -γ agonists would serve as an adjuvant therapy before radiotherapy if the clinical trials indicated positive from now on.