靶向与检测肿瘤亚细胞结构中氧化还原活性物种的长波长荧光探针的构建及其生物成像分析应用

The pathology, diagnosis and therapy of malignant tumor are the frontier issue of life science and medical research. Apoptosis plays a key role in the activation and inhibition of malignant tumors, while oxidative stress is an important part of cell apoptosis. Redox-active species are important biologically active molecules that change in the metabolic pathway of tumor cells and the study of these species during oxidative stress induced apoptosis is of great significance in the diagnosis and prognosis of malignant tumors. However, the design of redox-active species probes targeted to tumor cells and located in subcellular structures is relatively less, and excellent optical probes with high stability and long-wavelength emission are still lacking. To address this critical issue, we propose to develop long-wavelength emitted fluorescent probes those targeted to the subcellular structures of tumor cells for the detection of redox-active species selectively by taking the advantage of the specific chemical reaction to incorporate the targeted unit and recognized unit into the long-wavelength emitted dyes. Based on these probes, we can establish the analytical and imaging method for these active species, investigate the exact information of molecular events involved in the oxidative stress induced apoptosis and provide an effective technical platform for the targeted diagnosis and the treatment of the malignant, promoting the cognition of the mechanism of malignancy at the molecular level.

恶性肿瘤的病理、诊断及治疗是生命科学及医学研究领域的前沿性课题。细胞凋亡对恶性肿瘤的激活与抑制起着关键作用，而氧化应激是造成细胞凋亡的重要环节。氧化还原活性物种是在肿瘤细胞代谢途径中发生改变的生物活性分子，从分子层次上研究氧化应激诱导肿瘤细胞凋亡的发生和发展规律，对恶性肿瘤的诊断及预后判断有十分重要的意义。然而，目前靶向肿瘤细胞并定位于亚细胞结构的氧化还原活性物种探针的设计思路相对较少，且同时具有高稳定性和长波长发射的优良光学探针仍较缺乏。针对该问题，我们提出借助特异的化学反应，通过在长波长染料上引入靶向单元和识别单元，设计靶向肿瘤亚细胞结构对氧化还原活性物种选择性检测的长波长荧光探针，建立这些物种的荧光检测及原位成像分析新方法，有望获得氧化应激诱导细胞凋亡过程中活性物种参与分子事件的真实信息，为恶性肿瘤的靶向诊断与治疗提供有效的技术平台，以促进在分子水平上对恶性肿瘤发生机理的认识。

我们设计与合成了一系列具有高特异性、良好生物相容性和稳定性的新荧光探针；利用识别基团对目标物的特异性反应而引起荧光信号的改变，实现了目标物的高选择性检测，包括活性氧物种、谷胱甘肽、多硫化氢、CO、羧酸酯酶以及细胞微环境因素检测等探针；利用这些探针，建立了相关物质的荧光检测及原位分析新方法，结合荧光成像技术，分析了它们在组织、细胞、亚细胞线粒体等水平上变化行为。这些方法在相关疾病的早期诊断研究以及药物疗效评价等方面具有重要的应用前景。