青蒿素诱导垂体腺瘤细胞凋亡及其机制探讨

Artemisinins are recognized by the world as one of original drugs, study of its mechanism contributes to "secondary development" of traditional Chinese medicine. Pituitary adenomas are the most common intracranial tumors, the first-line drugs to promote the apoptosis of tumor cells and shrink the size of adenoma are unavailable so far. Our previous research confirmed that artemisinin can reduce the size of tumor, induce cell-apoptosis and lead to up-regulation of PTEN in pituitary adenoma. consequently, we propose a hypothesis that the apoptosis of tumor cells caused by the drug is regulated by PTEN/Akt pathway. In addition, our previous study found that miRNAs were involved in the development of pituitary adenomas, furthermore, recent studies have shown that miR-200c was significantly elevated in pituitary adenoma and played an important role in tumor cell apoptosis. Therefore, we investigated whether the apoptosis of pituitary adenoma cells caused by artemisinin is regulated by miR-200c via PTEN/Akt pathway. In view of the above scientific questions and hypotheses, this study aims to demonstrate molecular mechanism of anti-tumor effects of artemisinin in vitro and in vivo using the methods of immune electron microscopy, plasmid vector construction and dual luciferase reporter, etc, and provide high-quality drug candidates for the treatment of pituitary adenomas.

青蒿素作为我国极少数被世界承认的原创药物，对其作用机制的深入探讨有助于对传统中药的“二次开发“。垂体腺瘤是颅内最常见肿瘤，目前尚缺乏针对缩小肿瘤体积、诱导肿瘤细胞凋亡的一线药物。我们前期结果证实,青蒿素类药物能缩小肿瘤体积并诱导细胞凋亡，同时发现PTEN表达上调，那么该药诱导肿瘤细胞凋亡是否通过PTEN/Akt通路调控？我们研究发现miRNA参与垂体腺瘤的发生发展，并且最近研究表明miR-200c在患者肿瘤组织中表达明显升高，同时证实其参与肿瘤细胞凋亡。因此设想，青蒿素类药物诱导垂体腺瘤细胞凋亡是否通过miR-200c调控PTEN/Akt通路。针对以上问题及假设，本研究拟通过免疫电镜、质粒载体构建及双荧光素酶报告等方法，在体内、外证实miR-200c通过PTEN/Akt通路诱导肿瘤细胞凋亡是青蒿素类药物抗垂体腺瘤的分子机制，旨在为垂体腺瘤治疗提供优质的候选药物。

青蒿素作为我国极少数被世界承认的原创药物，对其作用机制的深入探讨有助于对传统中药的“二次开发”。研究发现，青蒿素类药物除了能有效治疗疟疾外，还发挥抗肿瘤作用。垂体腺瘤是颅内最常见肿瘤，目前，对垂体腺瘤的治疗药物主要针对控制其激素分泌，尚缺乏针对缩小肿瘤体积、诱导肿瘤细胞凋亡的一线药物。我们前期结果证实,青蒿素类药物能缩小肿瘤体积并诱导细胞凋亡，同时发现PTEN表达上调，并且研究表明miR-200c在患者肿瘤组织中表达明显升高，同时证实其参与肿瘤细胞凋亡。因此，本研究通过CCK8、western blot、电镜、质粒载体构建、双荧光素酶报告及线粒体膜电位检测等方法，进一步探究并证实了青蒿琥酯与溴隐亭联合用药通过miR-200c/ PTEN通路诱导了功能型垂体腺瘤细胞凋亡。在细胞器水平上，青蒿琥酯则在功能型垂体腺瘤细胞线粒体内积累，通过线粒体途径抑制线粒体呼吸功能，介导细胞凋亡。与功能型垂体腺瘤细胞的作用机制不同，青蒿琥酯处理无功能型垂体腺瘤细胞后溶酶体增多，并通过lncRNA-MEG3 / miR-525-5p/VMA21通路诱导自噬。本项目研究结果提示，青蒿琥酯能有效并安全地治疗功能型腺瘤和无功能型腺瘤，可作为垂体腺瘤治疗的优质候选药物。