Lu Junren, Cai Daming, Qian Long, Wang Yurong, Ai Shichao, Song Peng, Sun Feng, Sun Yiwen, Liang Mengjie, Jiang Hang, Wang Xingzhou, Wang Meng, Lu Xiaofeng, Guan Wenxian, Shen Xiaofei
State Key Laboratory of Pharmaceutical Biotechnology, Department of General Surgery, Nanjing Drum Tower Hospital, Drum Tower Clinical Medical College, Nanjing Medical University, Nanjing, China.
Division of Gastric Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
NPJ Precis Oncol. 2025 Jun 16;9(1):186. doi: 10.1038/s41698-025-01004-6.
Sorafenib is the main treatment for advanced hepatocellular carcinoma (HCC), but drug resistance limits its effectiveness. Evidence increasingly indicates that, in addition to targeting tyrosine kinases, sorafenib also induces ferroptosis. However, current studies have not fully clarified the relationship between ferroptosis and sorafenib treatment sensitivity. Our bioinformatics analysis identified that SIX Homeobox 2 (SIX2), known for maintaining cellular stemness via the Wnt signaling pathway, was significantly upregulated in sorafenib-resistant tissues. Overexpression and knockdown experiments revealed that altering SIX2 expression affected HCC cell sensitivity to sorafenib and involved the ferroptosis pathway, suggesting a regulatory role for SIX2 in ferroptosis. RNA sequencing and CUT&Tag analysis showed that SIX2 directly regulated methyltransferase 9 (METTL9) expression. Co-immunoprecipitation (Co-IP) assays confirmed that METTL9 bound to SLC7A11, enhancing its stability and reducing degradation, thus regulating ferroptosis. Importantly, the role of SIX2 in ferroptosis operated independently of the classical glutathione peroxidase 4 (GPX4) pathway. In vitro studies further supported these findings, demonstrating that SIX2 knockdown increased sorafenib-induced ferroptosis in HCC, while METTL9 overexpression largely counteracted the effects of SIX2 knockdown. In mouse models, overexpression of SIX2 increased tumor resistance to sorafenib. Our findings suggest that modulating the ferroptosis pathway through SIX2 could enhance sorafenib sensitivity. This study provides the first evidence that SIX2 influences ferroptosis via the METTL9-SLC7A11 axis, thereby sensitizing HCC cells to sorafenib. Reducing SIX2 expression could thus represent a promising strategy to improve the efficacy of sorafenib in advanced HCC.
索拉非尼是晚期肝细胞癌(HCC)的主要治疗药物,但耐药性限制了其疗效。越来越多的证据表明,索拉非尼除了靶向酪氨酸激酶外,还能诱导铁死亡。然而,目前的研究尚未完全阐明铁死亡与索拉非尼治疗敏感性之间的关系。我们的生物信息学分析发现,以通过Wnt信号通路维持细胞干性而闻名的Six同源盒蛋白2(SIX2)在索拉非尼耐药组织中显著上调。过表达和敲低实验表明,改变SIX2表达会影响HCC细胞对索拉非尼的敏感性,并涉及铁死亡途径,提示SIX2在铁死亡中具有调节作用。RNA测序和CUT&Tag分析表明,SIX2直接调节甲基转移酶9(METTL9)的表达。免疫共沉淀(Co-IP)实验证实,METTL9与溶质载体家族7成员11(SLC7A11)结合,增强其稳定性并减少降解,从而调节铁死亡。重要的是,SIX2在铁死亡中的作用独立于经典的谷胱甘肽过氧化物酶4(GPX4)途径。体外研究进一步支持了这些发现,表明敲低SIX2可增加索拉非尼诱导的HCC铁死亡,而METTL9过表达在很大程度上抵消了敲低SIX2的作用。在小鼠模型中,SIX2过表达增加了肿瘤对索拉非尼的耐药性。我们的研究结果表明,通过SIX2调节铁死亡途径可以增强索拉非尼的敏感性。本研究首次证明SIX2通过METTL9-SLC7A11轴影响铁死亡,从而使HCC细胞对索拉非尼敏感。因此,降低SIX2表达可能是提高索拉非尼在晚期HCC中疗效的一种有前景的策略。
Hypertension. 2025-7
Front Pharmacol. 2025-6-4
J Transl Med. 2024-9-10
Nucleic Acids Res. 2024-6-10
Cancer Cell. 2024-2-12
Cell Death Discov. 2023-11-28
Biomed Pharmacother. 2023-11
Cell Discov. 2023-4-4