Concordant and opposite roles of DNA-PK and the "facilitator of chromatin transcription" (FACT) in DNA repair, apoptosis and necrosis after cisplatin.
Concordant and opposite roles of DNA-PK and the "facilitator of chromatin transcription" (FACT) in DNA repair, apoptosis and necrosis after cisplatin.
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DOI：
10.1186/1476-4598-10-74
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发表时间：
2011-06-16
期刊：
影响因子：
37.3
通讯作者：
Lazaro JB
中科院分区：
文献类型：
--
作者：
Sand-Dejmek J;Adelmant G;Sobhian B;Calkins AS;Marto J;Iglehart DJ;Lazaro JB
含铂化疗会产生特定的 DNA 损伤，用于治疗多种人类实体瘤。最初对铂类药物敏感的肿瘤经常会产生耐药性。抑制 DNA 修复是增强顺铂有效性的潜在策略。顺铂治疗后，修复和凋亡之间的平衡决定癌细胞是增殖还是死亡。 DNA 依赖性蛋白激酶 (DNA-PK) 通过其 Ku 亚基与 DNA 双链断裂 (DSB) 结合，并启动非同源末端连接。 DNA-PK 的抑制使癌细胞对顺铂的杀伤变得敏感。本研究的目的是阐明 DNA-PK 对顺铂敏感性影响的机制。沉默 DNA-PK 催化亚基 (DNA-PKcs) 的表达可增加对顺铂的敏感性，并减少顺铂治疗后 γH2AX 的出现。我们通过其 Ku86 亚基纯化了 DNA-PK，并在顺铂治疗前后通过串联质谱法鉴定了相互作用因子。顺铂处理后 5 小时，结构特异性识别蛋白 1 (SSRP1)、Spt16 和 γH2AX 出现在 Ku86 复合物中。 SSRP1 和 Spt16 形成染色质转录促进子 (FACT)。顺铂诱导的 FACT 与 Ku86 和 γH2AX 的关联被 DNase 处理消除。在活细胞中，SSRP1 和 Ku86 被招募到激光束诱导的 DSB 位置。沉默 SSRP1 表达会增加对顺铂的敏感性并减少 γH2AX 的出现。然而，虽然在顺铂处理的细胞中沉默 SSRP1 会增加细胞凋亡和坏死，但 DNA-PKcs 沉默却相反，有利于细胞坏死而不是细胞凋亡。 DNA-PK 和 FACT 都在 DNA 修复中发挥作用。因此，两者都是治疗性抑制的假定目标。由于 DNA-PK 调节细胞凋亡，因此沉默 DNA-PKcs 会将顺铂处理的细胞重定向至坏死。然而，沉默 FACT 会导致细胞凋亡和坏死。癌症患者的靶向 DNA 修复可能会产生不同的治疗效果，具体取决于靶向因素所起的作用。
Platinum-containing chemotherapy produces specific DNA damage and is used to treat several human solid tumors. Tumors initially sensitive to platinum-based drugs frequently become resistant. Inhibition of DNA repair is a potential strategy to enhance cisplatin effectiveness. After cisplatin treatment, a balance between repair and apoptosis determines whether cancer cells proliferate or die. DNA-dependent protein kinase (DNA-PK) binds to DNA double strand breaks (DSBs) through its Ku subunits and initiates non-homologous end joining. Inhibition of DNA-PK sensitizes cancer cells to cisplatin killing. The goal of this study is to elucidate the mechanism underlying the effects of DNA-PK on cisplatin sensitivity. Silencing the expression of the catalytic subunit of DNA-PK (DNA-PKcs) increased sensitivity to cisplatin and decreased the appearance of γH2AX after cisplatin treatment. We purified DNA-PK by its Ku86 subunit and identified interactors by tandem mass spectrometry before and after cisplatin treatment. The structure specific recognition protein 1 (SSRP1), Spt16 and γH2AX appeared in the Ku86 complex 5 hours after cisplatin treatment. SSRP1 and Spt16 form the facilitator of chromatin transcription (FACT). The cisplatin-induced association of FACT with Ku86 and γH2AX was abrogated by DNase treatment. In living cells, SSRP1 and Ku86 were recruited at sites of DSBs induced by laser beams. Silencing SSRP1 expression increased sensitivity to cisplatin and decreased γH2AX appearance. However, while silencing SSRP1 in cisplatin-treated cells increased both apoptosis and necrosis, DNA-PKcs silencing, in contrast, favored necrosis over apoptosis. DNA-PK and FACT both play roles in DNA repair. Therefore both are putative targets for therapeutic inhibition. Since DNA-PK regulates apoptosis, silencing DNA-PKcs redirects cells treated with cisplatin toward necrosis. Silencing FACT however, allows both apoptosis and necrosis. Targeting DNA repair in cancer patients may have different therapeutic effects depending upon the roles played by factors targeted.
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影响因子：
14.9
作者：
Durant, S;Karran, P
通讯作者：
Karran, P
DOI：
10.1073/pnas.0406466102
发表时间：
2005-02-01
影响因子：
11.1
作者：
Convery, E;Shin, EK;Meek, K
通讯作者：
Meek, K
DOI：
10.1146/annurev.pathol.4.110807.092246
发表时间：
2009
期刊：
Annual review of pathology
影响因子：
--
作者：
Cho KR;Shih IeM
通讯作者：
Shih IeM
影响因子：
21.3
作者：
Lukas, C;Falck, J;Lukas, J
通讯作者：
Lukas, J
影响因子：
5.2
作者：
Dejmek, Janna;Iglehart, J. Dirk;Lazaro, Jean-Bernard
通讯作者：
Lazaro, Jean-Bernard