A study of the relationship of the radioresistance of esophageal carcinoma cell line TE13R120 with HDAC3, NF-kB and NRAGE

Objective: To evaluate the relationship of the radioresistance of esophageal carcinoma with genes HDAC3, NF-kB and NRAGE. Methods: Two cell lines are chosen for the study, esophageal carcinoma cell line TE13 and esophageal carcinomatous radioresistant cell line TE13R120 which is derived from TE13 by fractionated ionizing radiation. The protein expression of genes HDAC3, NF-kB and NRAGE were measured by Western blotting in the two cell lines at different time intervals and 12 h after different radiating dosages. Apoptotic cell population and cell cycle distribution of the two cell lines were detected by FCM through the same time and dosage-courses with above. Results: The protein expressions of NF-kB and HDAC3 in TE13R120 cells were elevated before and after radiation compared with those of TE13 cells. No change of NRAGE expression had been found in cytoplasma of TE13R120 cells compared with TE13 cells. The percentages of TE13R120 cells in G2 phase were increased at 4, 16 and 24 h after 4 Gy radiation and at 12 h after 2, 6 and 10 Gy radiation. In contrast, no significant change had been observed in TE13 in G2 phage after radiation. Additionally, the percentages of TE13R120 cells in S phage were significantly higher than those of TE13 cells before and 12 h after different doses radiation. The apoptosis percentages of TE13R120 cell is slightly higher than those of TE13. Conclusion: The increasing protein expression of HDAC3 and NF-kB in TE13R120 suggest a very important and possibly, a cooperative effect of these two genes to induce the radioresistance of TE13R120 cell. Further study should be done to reveal the relationship of NRAGE with the radioresistance of esophageal carcinoma. (authors)