Functional intravital imaging of the breast tumor invasion process in tumor microenvironment

基于荧光共振能量转移（FRET）原理的各种荧光生物传感器已被很好地用于可视化各种信号分子的体外活性。然而，活体组织实际上是由多种细胞和细胞在三维环境中的相互作用组成的。近年来的研究表明，肿瘤微环境是由肿瘤细胞和基质细胞组成的。本项目利用基因编码FRET生物传感器，在双光子显微镜下观察活鼠体内ERK、PKA和Rac1的分子活性，了解肿瘤微环境。在本项目中，我们培育了表达ERK和PKA的FRET生物传感器的转基因小鼠。此外，还开发了成像工具、稳定器和窗口，以获得无运动图像，并使小鼠存活。这些结果对肿瘤微环境的研究具有重要的推动作用。

A variety of fluorescent biosensors based on the principle of Fluorescence Resonance Energy Transfer (FRET) have been well used to visualize the activities of various signaling molecules in vitro. However, living tissues actually consist of many kinds of cells and cellular interactions in three-dimensional environments.Recent studies show the importance of tumor microenvironment comprising of tumor cells and stroma cells. In this project, molecular activities of ERK, PKA and Rac1 were visualized by using genetically-encoded FRET biosensors in living mice under two-photon microscope for the understanding of tumor microenvironment in vivo. We have developed transgenic mice which express FRET biosensors for ERK and PKA in this project. In addition, imaging tools, stabilizer and windows were developed to get motion-less images and keep mice alive. These results achieved by intravital imaging can progress the studies about tumor microenvironment.