基于核酸适体的膀胱癌相关分子标志物发现和可视化分析

The search of novel tumor-associated molecular biomarkers and development of visual imaging analysis methods for characteristic molecules in the process of tumor evolution will provide theoretical basis and technical support for elucidating the mechanism of tumor development, early diagnosis and personalized treatment. In view of the current lack of effective molecular biomarkers and clinical visualization probes for malignant bladder cancer, this project intends to use Cell-SELEX technology to screen targeted aptamers for bladder cancer cells with different infiltration characteristics, with normal bladder epithelial cells as a control. Nucleic acid aptamer probes that specifically recognizes invasive bladder cancer cells, use to find novel molecular biomarkers related to invasive bladder cancer; and combine chemical modification techniques to construct visualized nucleic acid aptamer probes with different imaging modalities (near-infrared fluorescence, MRI, etc.) for multimodal imaging analysis of bladder cancer model in situ. We next establish correlation mode between in vitro detection information, image signal, pathological features and molecular function, delineating molecular classification of bladder cancer, revealing bladder cancer infiltration. The molecular mechanism of metastasis provides scientific and feasible new ideas and strategies for early screening, accurate typing, medication guidance and effective evaluation of bladder cancer in China.

寻找新型肿瘤相关的分子标志物，发展肿瘤演进过程中特征分子的可视化成像分析方法，将为阐明肿瘤发生发展机制、肿瘤早期诊断和个性化治疗提供理论基础和技术支撑。针对恶性膀胱癌缺乏有效分子标志物和临床可视化探针的现状，本项目拟利用Cell-SELEX技术，以不同浸润特性的膀胱癌细胞为筛选对象，并以正常膀胱上皮细胞为对照，以期获得能特异性识别浸润性膀胱癌细胞的核酸适体；以此核酸适体为探针寻找浸润性膀胱癌相关的新型分子标志物；结合化学修饰技术构建不同成像模式的可视化核酸适体探针（近红外荧光、MRI等），用于原位膀胱癌模型的多模式成像分析；建立体外检测信息、影像信号、病理特征与分子功能之间的关联，描绘膀胱癌分子分型图谱，揭示膀胱癌浸润转移的分子机制，为我国膀胱癌早期筛查、精准分型、用药指导和疗效评估提供科学可行的新思路和新策略。

针对调控膀胱癌转移特性相关的细胞力学分子机制，通过Cell-SELEX技术，筛选得到一种靶向细胞骨架相关蛋白4（CKAP4）的核酸适体，称为spl3c。CKAP4与BLCA中的肿瘤转移有关，同时发现它也是细胞膜张力调控关键因子，能重塑细胞膜中心-边缘的张力梯度，促进膀胱癌细胞的迁移。同时，还能“搭乘”外泌体实现细胞间的力学信号传递，从而加剧膀胱癌在体内的转移。综上所述，这项研究利用核酸适体作为分子工具，发现了细胞膜张力调控关键因子-CKAP4，明确了其不仅能重塑细胞膜表面张力，而且还能经外泌体实现细胞间力学信号的传递，从而增强膀胱癌细胞的迁移能力，促进其体内的转移。该项研究利用多学科交叉优势，开拓了膀胱癌力学研究的新方向，为膀胱癌的防治提供了新思路。