A breakthrough in the research of high-sensitivity tumor imaging technology in the nude mouse model experiment of the Institute of Automation of the Chinese Academy of Sciences

  Early imaging of malignant tumors is very important for the clinical diagnosis and treatment of cancer patients, and is a long-term challenge for basic oncology research and clinical research around the world. The automated laboratory of the Chinese Academy of Sciences is the main laboratory for molecular imaging. It has successfully developed a new type of photonuclear multi-mode fusion molecular imaging technology (Radiopharmaceutical Excited Fluorescence Imaging, REFI), and has made significant progress in this field. The relevant research results were co-written by Associate Professor Hu Zhenhua and Associate Professor Wang Kun. The first author is the Institute of Automation, PLA General Hospital and Natural Communications Armed Police General Hospital (2015, 6: 7560. DOI: 10.1038). /ncomms8560) jointly announced. The author of this article is a fully localized scientific researcher, reflecting China's independent innovation ability and scientific research strength in cutting-edge medical imaging theory and technology. According to the latest statistics of the National Cancer Institute in 2014 (the statistical sample is about 2 million), from 1960 to the present, the 5-year survival time of various cancer patients has not increased significantly. , All less than 50%. Professor Bruce J. Hillman from the University of Virginia in the United States is a well-known scholar in the field of international medical imaging, and uses conventional clinical imaging techniques (such as CT imaging, magnetic resonance imaging and radionuclear PET imaging) to treat small tumors Early detection of lesions. (New England Journal of Medicine, 2010, 363(1): 4-6) pointed out that this is difficult to achieve. The main reason is that it is difficult to break through the sensitivity bottleneck of imaging technology, and it is impossible to effectively image small tumors with a diameter of less than 5 mm.

  The research team led by Tian Jie, a researcher at the Institute of Automation, identified the main scientific issues of the insensitive medical imaging technology in early tumor detection and the most sensitive radionuclear PET imaging among conventional imaging technologies. We aim to study the two modes of optical imaging in detail. Physical imaging principles and key imaging techniques. Through a series of basic theoretical studies and breakthroughs, the research team has replaced the traditional external source single-light excitation optical imaging with internal dual excitation imaging (ie, REFI imaging with high-energy gamma rays and low-energy Cherenkov fluorescent radiation). Recommended mode. This new imaging technology successfully combines the advantages of PET and radionuclide optical imaging. Compared with the low resolution of radionuclear PET imaging, REFI improves the marginal resolution from 2-3 mm to sub-millimeters at the optical macro level. Compared with external excitation fluorescence imaging, REFI averages the signal-to-noise ratio of the imaging. It has increased by more than 5 times. Based on the above advantages, REFI has broken through the sensitivity limit of traditional single-modal imaging and increased the detection sensitivity of non-invasive imaging for tumors in live animals from the minimum detection diameter of 5 mm to 2 mm (2 mm). as the picture shows. By comparing the image effects of different image modalities, it undoubtedly shows the sensitive tumor detection effect of REFI. In the figure, the same batch of breast cancer sympathetic nude mice models (figure a) grown for 36 hours (less than 2 mm in diameter) and 65 hours (about 5 mm in diameter) were subjected to multi-peak contrast imaging experiments. Among them, PET imaging can detect tumors only 65 hours after tumor growth (Figure B). Traditional Cerenkov fluorescence imaging (CLI) did not detect the tumor location in both experiments (Figure c, CLI). -Radionuclear fusion REFI successfully detected the tumor location at 36 and 65 hours (Figure C, REFI).

  Due to the superiority of ultra-sensitive REFI imaging in the early detection of small tumor lesions, a related research team of the Institute of Automation is transforming and applying this new technology to clinical medicine based on theoretical innovation and animal experiment verification. We are working hard to promote. This research work was also supported by related projects of the China Science, Technology and Nature Foundation and the Ministry of Science and Technology. It is hoped that related research and its clinical transformation will achieve major breakthroughs during the "13th Five-Year Plan" period.