DNA damage response in prostate cancer cells after high-intensity focused ultrasound (HIFU) treatment
Hisamitsu Ide1, Takashi Nakagawa, Yuichi Terado
1Department of Urology, Teikyo University School of Medicine, Itabashi-ku, Tokyo, Japan.
Background:
High-intensity focused ultrasound (HIFU) is a new modality that can be used for local tumor ablation therapy. In the present study, the expression of human checkpoint kinase2 (Chk2), which may have significant roles in the response to DNA damage after HIFU treatment for prostate cancer, was examined.
Materials And Methods:
By immunohistochemistry, the Chk2 expression in human prostate cancer tissues was examined before and after HIFU treatment. The phosphorylation of ataxia-telangiectasia-mutated kinase (ATM), histone H2A variant (H2AX), Chk2 and p53, and the number of apoptotic cells in human prostate cancer cell lines after heat treatment was checked.
Results:
The expression level of phosphorylated Chk2 was found to be increased after HIFU treatment. In addition, heat treatment induced the phosphorylation of Chk2 proteins examined and led to apoptosis in the prostate cancer cells.
Conclusion:
Our results suggest that DNA double-strand break formation is a possible pathway of HIFU treatment and leads to heat-induced cell killing.
