Reversing hypoxic cell chemoresistance in vitro using genetic and small molecule approaches targeting hypoxia inducible factor-1
Reversing hypoxic cell chemoresistance in vitro using genetic and small molecule approaches targeting hypoxia inducible factor-1
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DOI：
10.1124/mol.105.015743
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发表时间：
2006-02-01
影响因子：
3.6
通讯作者：
Williams, KJ
中科院分区：
文献类型：
--
作者：
Brown, LM;Cowen, RL;Williams, KJ
低氧细胞对常规化疗的抵抗性是有据可查的。使用腺病毒介导的基因递送和靶向低氧诱导因子-1（HIF-1）的小分子，我们评估了HIF-1抑制对低氧肿瘤细胞对依托泊苷敏感性的影响。基因疗法利用了一种截短的HIF-1 α蛋白，该蛋白充当显性负性HIF-1 α（HIF-1 α-no-alpha）。使用HIF-1报告基因测定在六种人肿瘤细胞系中验证了其功能。EGFP融合蛋白表明，显性负性HIF-1 α是核定位和组成型表达，而不管氧张力。研究的小分子是奎诺卡霉素单柠檬酸盐（KW 2152），其类似物7-氰基奎诺卡酚（DX-52-1）和拓扑替康。DX-52-1和拓扑替康先前已被确定为HIF-1抑制剂。HT 1080和HCT 116细胞用AdHIF-1 α-无毒性或无毒浓度（0.1 μ M; <IC 10）的KW 2152和DX-52-1处理，并暴露于空气中或缺氧（< 0.01%氧）中的依托泊苷。托泊替康仅在细胞毒性浓度下抑制HIF-1活性，未用于联合研究。缺氧条件下依托泊苷对HT 1080（2.2 +/- 0.3对0.7 +/- 0.2 μ M）和HCT 116（9 +/- 4对3 +/- 2 μ M）细胞的IC 50值比空气中的IC 50值高3倍。KW-2152和DX-52-1显著降低HT-1080细胞缺氧时足叶乙甙的IC_（50），而只有KW-2152对HCT-116细胞产生致敏作用。相比之下，AdHIF-1 α-无氧蛋白（感染复数50）消除了两种细胞系中的缺氧抗性（IC 50值：HT 1080，0.7 +/- 0.04 μ M; HCT 116，3 +/- 1 μ M）。缺氧条件下HIF-1 α-no表达抑制HIF-1介导的促凋亡蛋白Bid的下调。这些数据支持HIF-1靶向方法联合化疗的潜在发展，其中缺氧细胞抗性导致治疗失败。
The resistance of hypoxic cells to conventional chemotherapy is well documented. Using both adenovirus-mediated gene delivery and small molecules targeting hypoxia-inducible factor-1 (HIF-1), we evaluated the impact of HIF-1 inhibition on the sensitivity of hypoxic tumor cells to etoposide. The genetic therapy exploited a truncated HIF-1 alpha protein that acts as a dominant-negative HIF-1 alpha (HIF-1 alpha-no-TAD). Its functionality was validated in six human tumor cell lines using HIF-1 reporter assays. An EGFP-fused protein demonstrated that the dominant-negative HIF-1 alpha was nucleus-localized and constitutively expressed irrespective of oxygen tension. The small molecules studied were quinocarmycin monocitrate (KW2152), its analog 7-cyanoquinocarcinol (DX-52-1), and topotecan. DX-52-1 and topotecan have been previously established as HIF-1 inhibitors. HT1080 and HCT116 cells were treated with either AdHIF-1 alpha-no-TAD or nontoxic concentrations (0.1 mu M; < IC10) of KW2152 and DX-52-1 and exposed to etoposide in air or anoxia (< 0.01% oxygen). Topotecan inhibited HIF-1 activity only at cytotoxic concentrations and was not used in the combination study. Etoposide IC50 values in anoxia were 3-fold higher than those in air for HT1080 (2.2 +/- 0.3 versus 0.7 +/- 0.2 mu M) and HCT116 (9 +/- 4 versus 3 +/- 2 mu M) cells. KW2152 and DX-52-1 significantly reduced the anoxic etoposide IC50 in HT1080 cells, whereas only KW2152 yielded sensitization in HCT116 cells. In contrast, AdHIF-1 alpha-no-TAD( multiplicity of infection 50) ablated the anoxic resistance in both cell lines (IC50 values: HT1080, 0.7 +/- 0.04 mu M; HCT116, 3 +/- 1 mu M). HIF-1 alpha-no-TAD expression inhibited HIF-1-mediated down-regulation of the proapoptotic protein Bid under anoxia. These data support the potential development of HIF-1 targeted approaches in combination with chemotherapy, where hypoxic cell resistance contributes to treatment failure.