Our results are still preliminary, and further investigations are required to understand the mechanisms of the increased or decreased drug sensitivity in the radio-resistant cell line. As a next step, in vivo experiments Autophagy activator inhibitor would be necessary to confirm the relevance for radio-chemotherapy of cancer. A detailed understanding of the mechanisms of radiation-induced chemosensitivity may prove very helpful for choosing the sequence of radiotherapy and chemotherapy in esophageal cancer. Conclusion Our study demonstrated a significant association between the cellular radio-resistance

and the sensitivity of chemotherapeutic drugs in esophageal carcinoma cells. This result implied that doxorubicin, 5-fluorouracil, paclitaxel or etoposide will provide a more marked therapeutic effect for radio-resistant esophageal cancer. It will be important to confirm these findings and to

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