KU-0060648 inhibits hepatocellular carcinoma cells through DNA-PKcs-dependent and DNA-PKcs-independent mechanisms.
KU-0060648 inhibits hepatocellular carcinoma cells through DNA-PKcs-dependent and DNA-PKcs-independent mechanisms.
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KU-0060648 通过 DNA-PKcs 依赖性和 DNA-PKcs 独立机制抑制肝细胞癌细胞。
DOI：
10.18632/oncotarget.7742
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发表时间：
2016-03-29
期刊：
影响因子：
--
通讯作者：
Lu PH
中科院分区：
文献类型：
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作者：
Chen MB;Zhou ZT;Yang L;Wei MX;Tang M;Ruan TY;Xu JY;Zhou XZ;Chen G;Lu PH
我们在临床前肝细胞癌（HCC）模型中检测了KU-0060648的抗肿瘤活性。我们的研究结果表明，KU-0060648在已建立的（HepG2， Huh-7和KYN-2系）和原代人HCC细胞中具有抗增殖和促凋亡作用，但对非癌性HL-7702肝细胞无细胞毒性。DNA-PKcs （dna活化蛋白激酶催化亚基）是KU-0060648的重要靶点，但不是唯一的靶点。DNA-PKcs敲低或显性负突变抑制HCC细胞增殖。另一方面，野生型DNA-PKcs的过表达促进了HepG2细胞的增殖。重要的是，KU-0060648对dna - pkcs沉默或突变的HepG2细胞仍然具有细胞毒性，尽管其在这些细胞中的活性相对较弱。进一步的研究表明，KU-0060648抑制PI3K-AKT-mTOR的激活，不依赖于DNA-PKcs。引入组成活性AKT1 （CA-AKT1）恢复KU-0060648处理后HepG2细胞中AKT-mTOR的激活，并减轻随后的细胞毒性。在体内，腹腔注射KU-0060648可显著抑制裸鼠HepG2异种移植物的生长。在异种移植肿瘤中，AKT-mTOR的激活也受到抑制。最后，我们发现DNA-PKcs在人HCC组织中的表达显著上调。然而，miRNA-101（一种抗dna - pkcs的miRNA）被下调。HepG2细胞中过表达miR-101抑制DNA-PKcs的表达和细胞增殖。总之，这些结果表明KU-0060648通过dna - pkcs依赖性和非依赖性机制抑制HCC细胞。
Here we tested anti-tumor activity of KU-0060648 in preclinical hepatocellular carcinoma (HCC) models. Our results demonstrated that KU-0060648 was anti-proliferative and pro-apoptotic in established (HepG2, Huh-7 and KYN-2 lines) and primary human HCC cells, but was non-cytotoxic to non-cancerous HL-7702 hepatocytes. DNA-PKcs (DNA-activated protein kinase catalytic subunit) is an important but not exclusive target of KU-0060648. DNA-PKcs knockdown or dominant negative mutation inhibited HCC cell proliferation. On the other hand, overexpression of wild-type DNA-PKcs enhanced HepG2 cell proliferation. Importantly, KU-0060648 was still cytotoxic to DNA-PKcs-silenced or -mutated HepG2 cells, although its activity in these cells was relatively weak. Further studies showed that KU-0060648 inhibited PI3K-AKT-mTOR activation, independent of DNA-PKcs. Introduction of constitutively-active AKT1 (CA-AKT1) restored AKT-mTOR activation after KU-0060648 treatment in HepG2 cells, and alleviated subsequent cytotoxicity. In vivo, intraperitoneal (i.p.) injection of KU-0060648 significantly inhibited HepG2 xenograft growth in nude mice. AKT-mTOR activation was also inhibited in xenografted tumors. Finally, we showed that DNA-PKcs expression was significantly upregulated in human HCC tissues. Yet miRNA-101, an anti-DNA-PKcs miRNA, was downregulated. Over-expression of miR-101 in HepG2 cells inhibited DNA-PKcs expression and cell proliferation. Together, these results indicate that KU-0060648 inhibits HCC cells through DNA-PKcs-dependent and -independent mechanisms.