Iglesias-Corral Diego, García-Valles Paula, Arroyo-Garrapucho Nuria, Bueno-Martínez Elena, Ruiz-Robles Juan Manuel, Ovejero-Sánchez María, González-Sarmiento Rogelio, Herrero Ana Belén
Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain.
Molecular Medicine Unit, Department of Medicine, University of Salamanca, Salamanca, Spain.
Front Oncol. 2024 May 13;14:1390518. doi: 10.3389/fonc.2024.1390518. eCollection 2024.
Cancer is a global health problem accounting for nearly one in six deaths worldwide. Conventional treatments together with new therapies have increased survival to this devastating disease. However, the persistent challenges of treatment resistance and the limited therapeutic arsenal available for specific cancer types still make research in new therapeutic strategies an urgent need.
Chloroquine was tested in combination with different drugs (Panobinostat, KU-57788 and NU-7026) in 8 human-derived cancer cells lines (colorectal: HCT116 and HT29; breast: MDA-MB-231 and HCC1937; glioblastoma: A-172 and LN-18; head and neck: CAL-33 and 32816). Drug´s effect on proliferation was tested by MTT assays and cell death was assessed by Anexin V-PI apoptosis assays. The presence of DNA double-strand breaks was analyzed by phospho-H2AX fluorescent staining. To measure homologous recombination efficiency the HR-GFP reporter was used, which allows flow cytometry-based detection of HR stimulated by I-SceI endonuclease-induced DSBs.
The combination of chloroquine with any of the drugs employed displayed potent synergistic effects on apoptosis induction, with particularly pronounced efficacy observed in glioblastoma and head and neck cancer cell lines. We found that chloroquine produced DNA double strand breaks that depended on reactive oxygen species formation, whereas Panobinostat inhibited DNA double-strand breaks repair by homologous recombination. Cell death caused by chloroquine/Panobinostat combination were significantly reduced by N-Acetylcysteine, a reactive oxygen species scavenger, underscoring the pivotal role of DSB generation in CQ/LBH-induced lethality. Based on these data, we also explored the combination of CQ with KU-57788 and NU-7026, two inhibitors of the other main DSB repair pathway, nonhomologous end joining (NHEJ), and again synergistic effects on apoptosis induction were observed.
Our data provide a rationale for the clinical investigation of CQ in combination with DSB inhibitors for the treatment of different solid tumors.
癌症是一个全球性的健康问题，全球近六分之一的死亡由其导致。传统治疗方法与新疗法相结合，提高了这种毁灭性疾病患者的生存率。然而，治疗耐药性这一持续存在的挑战以及针对特定癌症类型的治疗手段有限，使得新型治疗策略的研究仍迫在眉睫。
在8种人源癌细胞系（结直肠癌：HCT116和HT29；乳腺癌：MDA-MB-231和HCC1937；胶质母细胞瘤：A-172和LN-18；头颈部：CAL-33和32816）中，将氯喹与不同药物（帕比司他、KU-57788和NU-7026）联合进行测试。通过MTT法检测药物对增殖的影响，并通过膜联蛋白V-碘化丙啶凋亡检测法评估细胞死亡情况。通过磷酸化组蛋白H2AX荧光染色分析DNA双链断裂的存在。为了测量同源重组效率，使用了HR-GFP报告基因，其可通过基于流式细胞术检测由I-SceI核酸内切酶诱导的双链断裂所刺激的同源重组。
氯喹与所使用的任何一种药物联合使用时，对细胞凋亡诱导均显示出强大的协同作用，在胶质母细胞瘤和头颈部癌细胞系中观察到特别显著的疗效。我们发现氯喹产生的DNA双链断裂依赖于活性氧的形成，而帕比司他通过同源重组抑制DNA双链断裂的修复。活性氧清除剂N-乙酰半胱氨酸可显著减少氯喹/帕比司他联合用药导致的细胞死亡，这突出了双链断裂生成在氯喹/帕比司他诱导的细胞死亡中的关键作用。基于这些数据，我们还探索了氯喹与KU-57788和NU-7026（另一种主要双链断裂修复途径——非同源末端连接（NHEJ）的两种抑制剂）的联合使用，同样观察到对细胞凋亡诱导的协同作用。
我们的数据为氯喹与双链断裂抑制剂联合用于治疗不同实体瘤的临床研究提供了理论依据。
