新型硫氧还蛋白还原酶荧光探针的构建及在肿瘤靶向成像诊疗中的应用

Thioredoxin reductase (TrxR) is high expression in a variety of tumors, plays an important role in the regulation of tumor cells oxidative stress, proliferation, drug resistance and apoptosis. However, its fluorescent probes are scarce，narrow application range, and the function is single, so it has not been applied in vivo research. Our previous works have reported a novel fluorescenct molecular probe TPP2a to image of mitochondrial TrxR in Hela cells. Based on this foundation, we combine the aggregation-induced emission strategy with the photodynamic therapy, construction a series of novel multi-functional TrxR-targeted and near-infrared fluorescence molecular probes. The binding mode and mechanism of probes to TrxR are analyzed by fluorescence detection, western blotting. The intracellular imaging of TrxR is evaluated by laser confocal microscopy. In addition, we will construct a nude mouse xenograft tumor model to evaluate the application of molecular probes in vivo imaging. At the same time, the photodynamic therapy of probes in cells and mice are explored under light radiation. The goal of this study is to construct an innovative and with photodynamic therapy multifunctional fluorescent molecular probes in vitro and in vivo targeting TrxR. This work will provide the experimental basis for the labeling imaging of TrxR and the development of multi-functional diagnostic molecular probes with anti-tumor effect.

硫氧还蛋白还原酶（TrxR）在肿瘤组织中高表达，在调控细胞氧化应激过程中起着关键作用，并广泛参与肿瘤细胞的增殖、耐药、凋亡等过程。但现有的TrxR荧光分子探针较少、应用范围窄、功能单一、尚未能应用于体内研究。前期工作中我们已报道了一种荧光探针TTP2a，可对细胞内线粒体TrxR靶向成像。在此基础上，我们采用聚集诱导发光与光动力治疗相结合的策略，构建可发射近红外光的多功能靶向TrxR荧光探针。采用荧光、免疫印迹等方法解析探针与TrxR在分子水平的结合模式与作用机制,运用激光共聚焦显微镜实时观测探针在细胞内的靶向成像作用。通过构建裸鼠移植瘤模型评价探针在活体成像中的应用，并在光辐射下考察探针在体内外光动力治疗效果。通过本项目靶向成像TrxR的新型多功能荧光探针的构建、作用机制研究及治疗效果的评价，为TrxR的标记成像和研发具有抗肿瘤作用的多功能诊疗型分子探针提供实验依据和研究基础。

本研究2020年经费下拨到校后正式开始，根据研究计划及实际研究调整，基本按时完成了项目的主要内容，同时在本项目的开展过程中，进一步丰富了研究内容，发表的相关的研究论文4篇，获得授权发明专利1项。研究工作主要集中在：1）靶向硫氧还蛋白还原酶的探针分子研究；2）吲哚-查尔酮衍生物双靶向硫氧还蛋白还原酶和微管的作用机制研究；3）葫芦素B通过铁死亡途径诱导鼻咽癌细胞死亡的分子机制研究；4）基于天然产物Millepachine的吲哚衍生物设计合成及其抗肿瘤机制研究。在课题执行期间，正式发表了3篇SCI研究论文，获授权发明专利1项，本项目研究成果为发展新型抗肿瘤探针分子提供了重要研究基础。