
Silencing of MBD1 reverses pancreatic cancer therapy resistance through inhibition of DNA damage repair
Author(s) -
Jin Xu,
Wenwei Zhu,
Wei Xu,
Xiaobo Cui,
Leon Chen,
Shunrong Ji,
Yi Qin,
Wantong Yao,
Liang Liu,
Chen Liu,
Jiang Long,
Min Li
Publication year - 2013
Publication title -
international journal of oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.405
H-Index - 122
ISSN - 1019-6439
DOI - 10.3892/ijo.2013.1901
Subject(s) - dna damage , dna repair , gene silencing , biology , cisplatin , cancer research , gene knockdown , cancer , g2 m dna damage checkpoint , microbiology and biotechnology , cell cycle , dna , cell cycle checkpoint , apoptosis , genetics , gene , chemotherapy
High resistance to traditional chemo- and radiotherapies contributes to the poor prognosis of pancreatic cancer (PC). Methyl-CpG binding domain protein 1 (MBD1), which plays an important role in disease progression, contributes to the drug resistance of PC cells; however, the mechanism underlying the drug resistance endowed by MBD1 remains unknown. In this study, we found that MBD1 was recruited to DNA damage sites under DNA damage conditions. Silencing of MBD1 significantly impaired activation of the DNA damage checkpoint response and inhibited DNA repair capacity. MBD1 binds mediator of DNA damage checkpoint protein 1 (MDC1), which is induced by radiation and regulates NBS1 activation in the presence of DNA damage repair. Knockdown of MBD1 significantly increased the sensitivity of cells to radiation and cisplatin (diamindichloridoplatin, DDP) in vitro. Importantly, the function of MBD1 in regulating chemoradioresistance is also partially dependent on DNA damage repair. Thus, we hypothesize that MBD1 may promote PC chemoradioresistance by regulating PC cell fate in the presence of DNA damage. Collectively, these findings reveal an important function of MBD1 in DNA repair and mediation of chemoradioresistance of cancer cells. Moreover, this study suggests that MBD1 is a promising molecular target for sensitizing resistant PC tumor cells to chemoradiotherapy.