Adenovirus-mediated expression of Tob1 sensitizes breast cancer cells to ionizing radiation

作者：Yang Jiao; Chun-min Ge; Qing-hui Meng; Jian-ping Cao; Jian Tong; Sai-jun Fan^*

来源：Acta Pharmacologica Sinica, 2007, 28(10): 1628-1636.

DOI：10.1111/j.1745-7254.2007.00647.x

• Tob1
• breast cancer
• radiosensitivity
• radiation

Aim: To investigate the effect of the Tob1 gene, a member of the Transducing Molecule of ErbB2/B-cell Translocation Ggene (TOB/BTG) family, by using the adenovirus-mediated expression of Tob1 on radiosensitivity in a human breast cancer cell line MDA-MB-231. Methods: Cell survival was determined by clonogenic assay. Apoptosis was evaluated by DNA fragmentation gel electrophoresis and terminal deoxynucleotidyl transferase-mediated nick end labeling assay. Protein expression was analyzed by Western blot assay and DNA repair was measured by a host cell reactivation assay. Results: We demonstrated that pre-irradiation treatment with Ad5-Tob1 significantly increased radiosensitivity, accompanying the increased induction of apoptosis and the repression of DNA damage repair. Furthermore, Ad5-Tob1-mediated radiosensitivity correlates with the upregulation of the pro-apoptotic protein Bax and the downregulation of several DNA double strand break repair proteins, including DNA-dependent protein kinases, Ku70 and Ku80, and X-ray-sensitive complementation group 4. Conclusion: Tob1, as a new radiosensitizer, is a new target in the radiotherapy of breast cancer via increasing apoptosis and suppressing DNA repair.

• 出版日期2007-10
• 单位苏州大学