宫颈癌是由高危人乳头瘤病毒 (HR-HPV) 持续感染以及 E6 和 E7 癌蛋白表达引起的。 E6 和 E7 损害 p53 和 Rb、G1-S 细胞周期检查点和 ATM 介导的 DNA 损伤修复 (DDR) 的活性，这反过来又增加了 G2 细胞周期检查点对 ATR 和 PARP 介导的 DDR 的依赖。本研究旨在确定 ATR 抑制剂（ATRi、AZD6738）和 PARP 抑制剂（PARPi、AZD2281）对 HR-HPV 宫颈癌细胞系的影响。ATRi 和 PARPi 单独或联合使用对代谢活力的影响、体外评估宫颈癌细胞系的细胞周期停滞、细胞凋亡和DDR通路，并使用异种移植模型评估体内肿瘤反应。宫颈癌细胞对ATRi和PARPi单一疗法敏感。由于 ATRi 介导的 PARP 表达上调，联合疗法仅在先接触 ATRi，然后接触 PARPi 时才在降低代谢活力方面具有协同作用。 ATRi 和 PARPi 的组合诱导 G2 细胞周期停滞和细胞凋亡。 PARPi 诱导 DNA 损伤和 γH2AX 磷酸化，ATRi 处理进一步增强这种磷酸化。然而，ATRi 处理减少了 PARPi 诱导的 Rad51 灶形成，表明同源重组修复受到抑制。 ATRi 显着减少宫颈癌异种移植肿瘤的生长，并且不受所研究剂量的同时 PARPi 治疗的影响。我们的研究结果表明，ATRi 增加了对 PARP 代谢活力的依赖，ATRi 和 PARPi 的组合在体外诱导宫颈癌的合成致死率，并且减少体内肿瘤负荷。版权所有 © 2024 Elsevier Inc. 保留所有权利。

Cervical cancer results from persistent infection with high-risk human papillomavirus (HR-HPV) and the expression of E6 and E7 oncoproteins. E6 and E7 compromise the activity of p53 and Rb, the G1-S cell cycle checkpoint, and ATM-mediated DNA damage repair (DDR), which in turn increases reliance on ATR- and PARP-mediated DDR at the G2 cell cycle checkpoint. This study aimed to determine the effects of an ATR inhibitor (ATRi, AZD6738) and a PARP-inhibitor (PARPi, AZD2281) on HR-HPV+ cervical cancer cell lines.The effects of ATRi and PARPi, alone and in combination, on metabolic viability, cell cycle arrest, apoptosis, and DDR pathways in cervical cancer cell lines were evaluated in vitro, and the in vivo tumor response was evaluated using a xenograft model.Cervical cancer cells were sensitive to ATRi and PARPi monotherapy. The combination therapy was only synergistic in reducing metabolic viability when exposed to ATRi first, followed by PARPi, owing to ATRi-mediated upregulation of PARP expression. Combination of ATRi and PARPi induced G2 cell cycle arrest and apoptosis. PARPi induced DNA damage and γH2AX phosphorylation, which was further increased by ATRi treatment. However, PARPi-induced Rad51 foci formation was reduced by ATRi treatment, suggesting the inhibition of homologous recombination repair. ATRi significantly reduced cervical cancer xenograft tumor growth and was not affected by simultaneous PARPi treatment at the doses studied.Our findings show that ATRi increased reliance on PARP for metabolic viability, the combination of ATRi and PARPi induced synthetic lethality in cervical cancer in vitro, and reduced tumor burden in vivo.Copyright © 2024 Elsevier Inc. All rights reserved.