Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
Shanghai Geriatric Institute of Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200031, China.
Int J Med Sci. 2022 Sep 25;19(11):1680-1694. doi: 10.7150/ijms.73701. eCollection 2022.
Gastric cancer is a highly malignant tumor. Gastric cancer stem cells (GCSCs) are the main causes of drug resistance, metastasis, recurrence, and poor prognosis. As a secondary metabolite of lichen, Atranorin has a variety of biological effects, such as antibacterial, anti-inflammatory, analgesic, and wound healing; however, its killing effect on GCSCs has not been reported. In this study, we constructed Atranorin complexes comprising superparamagnetic iron oxide nanoparticles (SPION) (Atranorin@SPION). and experiments confirmed that Atranorin@SPION could significantly inhibit the proliferation, invasion, angiogenesis, and tumorigenicity of CD44+/ CD24+ GCSCs, and induce oxidative stress injury, Fe+ accumulation, and ferroptosis. Quantitative real-time reverse transcription PCR and western blotting results showed that Atranorin@SPION not only reduced the expression levels of GCSC stem cell markers and cell proliferation and division markers, but also significantly inhibited the expression levels of key molecules in the cystine/glutamate transporter (Xc-)/glutathione peroxidase 4 (GPX4) and Tet methylcytosine dioxygenase (TET) family proteins. The results of high performance liquid chromatography-mass spectrometry and Dot blotting showed that Atranorin@SPION significantly inhibited the mRNA 5‑hydroxymethylcytidine modification of GCSCs. Meanwhile, the results of RNA immunoprecipitation-PCR also indicated that Atranorin@SPIONs significantly reduced the 5-hydroxymethylcytidine modification level of and mRNA 3' untranslated region in GCSCs, resulting in a decrease in their stability, shortening their half-lives and reducing translation activity. Therefore, this study revealed that Atranorin@SPIONs induced ferroptosis of GCSCs by weakening the expression of the Xc-/GPX4 axis and the 5-hydroxymethylcytidine modification of mRNAs in the pathway, thereby achieving their therapeutic effect on gastric cancer.
胃癌是一种高度恶性的肿瘤。胃癌干细胞（GCSCs）是导致药物耐药性、转移、复发和预后不良的主要原因。作为地衣的一种次生代谢产物，松萝酸具有多种生物效应，如抗菌、抗炎、镇痛和伤口愈合等；然而，其对 GCSCs 的杀伤作用尚未见报道。在本研究中，我们构建了包含超顺磁性氧化铁纳米粒子（SPION）的松萝酸复合物（Atranorin@SPION）。实验证实，Atranorin@SPION 可显著抑制 CD44+/CD24+ GCSCs 的增殖、侵袭、血管生成和致瘤性，并诱导氧化应激损伤、Fe+积累和铁死亡。实时定量逆转录 PCR 和 Western blot 结果显示，Atranorin@SPION 不仅降低了 GCSC 干细胞标志物和细胞增殖及分裂标志物的表达水平，还显著抑制了胱氨酸/谷氨酸转运体（Xc-）/谷胱甘肽过氧化物酶 4（GPX4）和 Tet 甲基胞嘧啶双加氧酶（TET）家族蛋白关键分子的表达水平。高效液相色谱-质谱联用和 Dot blot 结果表明，Atranorin@SPION 显著抑制了 GCSCs 的 mRNA 5-羟甲基胞嘧啶修饰。同时，RNA 免疫沉淀-PCR 结果也表明，Atranorin@SPIONs 显著降低了 GCSCs 中 和 mRNA 3'非翻译区的 5-羟甲基胞嘧啶修饰水平，导致其稳定性降低，半衰期缩短，翻译活性降低。因此，本研究揭示了 Atranorin@SPIONs 通过减弱 Xc-/GPX4 轴和途径中 mRNAs 的 5-羟甲基胞嘧啶修饰的表达，诱导 GCSCs 发生铁死亡，从而实现对胃癌的治疗作用。
