Lin Sheng-Ping, Huang Feng-Ying, Wu Ri-Hong, Xie Wei-Jing, Chen Ming-Hui, Dai Shu-Zhen, Xu Wen-Tian, Zheng Wu-Ping, Tan Guang-Hong
NHC Key Laboratory of Tropical Disease Control & The Second Affiliated Hospital, Hainan Medical University, 3 Xueyuan Road, Longhua District, Haikou City, 571199, Hainan Province, China.
Discov Oncol. 2025 May 15;16(1):772. doi: 10.1007/s12672-025-02333-5.
Recent studies have identified novel cardiac glycosides from natural sources with potential anti-tumor properties. Toxicarioside H (ToxH) is a novel cardiac glycoside isolated by our collaborative research team. However, its ability to induce ferroptosis in triple-negative breast cancer (TNBC) cells has not been investigated. Therefore, this study evaluates whether ToxH has the capability of inducing ferroptosis and elucidates the underlying molecular mechanisms. Treatment with ToxH led to dose- and time-dependent growth inhibition in BT-549 and MDA-MB-468 cells. Flow cytometry analysis and lactate dehydrogenase assay revealed that ToxH induced various forms of cell death in both BT-549 and MDA-MB-468 cells. Examination through transmission electron microscopy, along with flow cytometry analysis of 7-AAD-stained dead cells and ferroptosis markers BODIPY-C11 and Fe ions, identified various forms of cell death induced by ToxH, including apoptosis, autophagy, apoptotic necrosis, and ferroptosis. Co-treatment with the ferroptosis inhibitor Fer-1 significantly reduced ToxH-induced cell death, indicating that ToxH primarily inhibits TNBC cell growth by inducing ferroptosis. Further investigation into the molecular mechanisms revealed upregulation of Nrf2 and HO-1 expression by ToxH. Effective inhibition of ToxH-induced ferroptosis was achieved through shRNA-mediated knockdown of HO-1 expression. Animal experiments demonstrated that ToxH treatment markedly suppressed tumor growth compared to the control group, while co-administration of Fer-1 led to an increase in tumor growth. These findings suggest that ToxH suppresses TNBC cell growth by modulating the Nrf2/HO-1 signaling pathway to induce ferroptosis. ToxH presents itself as a promising cardiac glycoside compound for TNBC treatment, warranting further translational research.
最近的研究已经从天然来源中鉴定出具有潜在抗肿瘤特性的新型强心苷。毒毛旋花子苷H（ToxH）是我们合作研究团队分离出的一种新型强心苷。然而，其在三阴性乳腺癌（TNBC）细胞中诱导铁死亡的能力尚未得到研究。因此，本研究评估了ToxH是否具有诱导铁死亡的能力，并阐明其潜在的分子机制。用ToxH处理导致BT - 549和MDA - MB - 468细胞出现剂量和时间依赖性的生长抑制。流式细胞术分析和乳酸脱氢酶测定表明，ToxH在BT - 549和MDA - MB - 468细胞中诱导了多种形式的细胞死亡。通过透射电子显微镜检查，以及对7 - AAD染色的死亡细胞和铁死亡标志物BODIPY - C11和铁离子的流式细胞术分析，确定了ToxH诱导的多种形式的细胞死亡，包括凋亡、自噬、凋亡性坏死和铁死亡。与铁死亡抑制剂Fer - 1共同处理显著降低了ToxH诱导的细胞死亡，表明ToxH主要通过诱导铁死亡来抑制TNBC细胞生长。对分子机制的进一步研究揭示了ToxH上调了Nrf2和HO - 1的表达。通过shRNA介导的HO - 1表达敲低有效抑制了ToxH诱导的铁死亡。动物实验表明，与对照组相比，ToxH处理显著抑制了肿瘤生长，而同时给予Fer - 1则导致肿瘤生长增加。这些发现表明，ToxH通过调节Nrf2/HO - 1信号通路诱导铁死亡来抑制TNBC细胞生长。ToxH是一种有前景的用于TNBC治疗的强心苷化合物，值得进一步的转化研究。
