PO.ET08.03 · 实验与分子治疗
阻断hERG1增强胶质母细胞瘤的放射敏感化
Blocking hERG1 enhances radiation sensitization in glioblastoma
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：胶质母细胞瘤（GBM）是成人最具侵袭性的原发性脑肿瘤，中位生存期不足两年。不良预后部分是由抵抗放射并使肿瘤再增殖的胶质瘤干细胞（GSCs）所驱动。电压门控钾通道hERG1（KCNH2）在GBM中上调，并与治疗抗性相关，提示其抑制可能改善放疗疗效。
方法：将人GBM细胞系LN-229和患者来源的GSC细胞系GNS144培养为球体。测定了选择性hERG1抑制剂E-4031的IC₅₀值（LN-229为192.9 μM，GNS144为94.23 μM）。用各自的IC₅₀浓度的E-4031（或载体）处理细胞，并以单次分割0 Gy或10 Gy照射。7-14天后进行球体形成试验并定量。通过流式细胞术评估细胞周期分布。所有实验均一式三份进行；采用Tukey或Fisher LSD检验评估统计学显著性（p<0.05）。
结果：在LN-229球体中，E-4031联合放射的联合治疗比单独放射（+14.4%，p=0.0041）或单独E-4031（+23.56%，p=0.0002）更大程度地减少了球体形成。在GNS144中，联合治疗也优于单独放射（+25.80%，p=0.0303）和单独E-4031（+26.15%，p=0.0283）。LN-229的细胞周期分析显示，与对照组相比，E-4031使S期细胞群减少了5.95%（p=0.0054），当与放射联合时，S期细胞群额外减少了7.36%（p=0.0016）。
结论：用E-4031选择性阻断hERG1显著使GBM细胞放射敏感化，在球体形成能力（一种干性替代指标）方面产生协同性降低。此外，hERG1抑制减少了具放射抗性的S期细胞群。这些发现提示，hERG1阻断可能有利于GBM的放射敏感化，进一步探索hERG1靶向策略可能改善胶质母细胞瘤患者的预后。
查看英文原文 English abstract
Background: Glioblastoma (GBM) is the most aggressive primary brain tumor in adults, with a median survival of less than two years. Poor outcomes are driven in part by glioma stem cells (GSCs) that resist radiation and repopulate the tumor. The voltage gated potassium channel hERG1 (KCNH2) is upregulated in GBM and linked to therapy resistance, suggesting that its inhibition might improve radiotherapy efficacy.
Methods: Human GBM cell line LN‑229 and patient derived GSC line GNS144 were cultured as spheres. IC₅₀ values for the selective hERG1 inhibitor E‑4031 were determined (192.9 µM for LN‑229, 94.23 µM for GNS144). Cells were treated with the respective IC₅₀ concentration of E‑4031 (or vehicle) and irradiated with a single fraction of 0 Gy or 10 Gy. Sphere formation assays were performed and quantified 7-14 days later. Cell‑cycle distribution was assessed by flow cytometry. All experiments were performed in triplicate; statistical significance was evaluated with Tukey's or Fisher's LSD tests (p < 0.05).
Results: In LN‑229 spheres, combination therapy with E‑4031 and radiation reduced sphere formation more than radiation alone (+14.4 %, p = 0.0041) or E‑4031 alone (+23.56 %, p = 0.0002). In GNS144, the combination also performed better than radiation alone (+25.80 %, p = 0.0303) and E‑4031 alone (+26.15 %, p = 0.0283). Cell cycle analysis of LN‑229 showed that E‑4031 decreased the S‑phase population by 5.95 % (p = 0.0054) compared with controls, and when combined with radiation it reduced the S‑phase population by an additional 7.36 % (p = 0.0016).
Conclusions: Selective blockade of hERG1 with E‑4031 markedly radiosensitizes GBM cells, producing synergistic reductions in sphere forming capacity, a surrogate for stemness. Moreover, hERG1 inhibition decreases the radioresistant S‑phase cell population. These findings suggest that hERG1 blockade may be beneficial for radiosensitization in GBM, and further exploration of hERG1 targeted strategies could improve outcomes for patients diagnosed with glioblastoma.
利益披露 Disclosure
H. E. Goen, None..
N. Ohuabunwa, None..
J. D. Rodgers Gochicoa, None..
T. Huang, None..
K. B. Pointer, None.