Roles of DNA topoisomerase II isozymes in chemotherapy and secondary malignancies

Anna M. Azarova, Yi Lisa Lyu, Chao P. Lin, Yuan Chin Tsai, J. Y N Lau, James C. Wang, Leroy F. Liu

研究成果: 雜誌貢獻文章同行評審

240 引文 斯高帕斯(Scopus)


Drugs that target DNA topoisomerase II (Top2), including etoposide (VP-16), doxorubicin, and mitoxantrone, are among the most effective anticancer drugs in clinical use. However, Top2-based chemotherapy has been associated with higher incidences of secondary malignancies, notably the development of acute myeloid leukemia in VP-16-treated patients. This association is suggestive of a link between carcinogenesis and Top2-mediated DNA damage. We show here that VP-16-induced carcinogenesis involves mainly the β rather than the α isozyme of Top2. In a mouse skin carcinogenesis model, the incidence of VP-16-induced melanomas in the skin of 7,12-dimethylbenz[a]anthracene-treated mice is found to be significantly higher in TOP2β+ than in skin-specific top2β-knockout mice. Furthermore, VP-16-induced DNA sequence rearrangements and double-strand breaks (DSBs) are found to be Top2β-dependent and preventable by cotreatment with a proteasome inhibitor, suggesting the importance of proteasomal degradation of the Top2β-DNA cleavage complexes in VP-16-induced DNA sequence rearrangements. VP-16 cytotoxicity in transformed cells expressing both Top2 isozymes is, however, found to be primarily Top2α-dependent. These results point to the importance of developing Top2α-specific anticancer drugs for effective chemotherapy without the development of treatment-related secondary malignancies.
頁(從 - 到)11014-11019
期刊Proceedings of the National Academy of Sciences of the United States of America
出版狀態已發佈 - 6月 26 2007

ASJC Scopus subject areas

  • 多學科


深入研究「Roles of DNA topoisomerase II isozymes in chemotherapy and secondary malignancies」主題。共同形成了獨特的指紋。