Upregulation of Ku Expression in Human Neuroectodermal Tumor Cells after Retroviral DNA Integration

Abstract

Objective: To examine the expression of DNA-dependent protein kinase (DNA-PK); including DNA-PKcs, Ku70 and Ku80 in human neuroectodermal tumor cells with or without retroviral DNA integration. Methods: RT-PCR assay was used to examine the transcript of DNA-PK. Western blot and immunocytochemistry assays were used to examine the protein level of DNA-PK. Results: The expression of DNA-PKcs was similar in the cells with or without retroviral DNA integration, but the expression of Ku (both mRNA and protein for Ku70 and only protein for Ku80) was higher in cells with retroviral DNA integration than in cells without retroviral DNA integration. Conclusion: The expression of Ku but not the expression of DNA-PKcs is induced by retroviral DNA integration. Ku70 may play an important role in the regulation of Ku function in response to retroviral DNA integration.