TY - JOUR T1 - Survivin May Enhance DNA Double-strand Break Repair Capability by Up-regulating Ku70 in Human KB Cells JF - Anticancer Research JO - Anticancer Res SP - 223 LP - 228 VL - 29 IS - 1 AU - GAOFENG JIANG AU - BO REN AU - LEI XU AU - SHIZHEN SONG AU - CHANGCAI ZHU AU - FANGLI YE Y1 - 2009/01/01 UR - http://ar.iiarjournals.org/content/29/1/223.abstract N2 - Background: Survivin, expressed in almost all types of human malignancies, functions as a key factor in radioresistance primarily by inhibiting apoptosis. This study was conducted to investigate whether survivin plays a role in the DNA repair process in the KB human squamous cell carcinoma cell line. Materials and Methods: A stable KB cell line overexpressing survivin was established through the use of pIRES2-EGFP vector containing the coding region of survivin. Cells were then irradiated with X-rays and evaluated for DNA double-strand breaks (DSBs) by comet assay and flow cytometry for phospho-histone γH2AX. The protein levels of some DSB repair genes were detected by Western blotting analysis. Results: Comet assay and flow cytometry for phospho-histone γH2AX showed that overexpression of survivin resulted in significantly fewer DSBs in irradiated cells. Among the DSB repair genes detected, the protein level of Ku70 was up-regulated in survivin-overexpressing KB cells. Conclusion: This finding suggests that survivin may enhance DSB repair capability in KB cells by up-regulating Ku70. Copyright© 2009 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved ER -