CINCINNATI, May 15, 2014 — Certain types of brain tumors are difficult to image and detect, making them even more difficult to treat. A team from the Cincinnati Cancer Center and the University of Cincinnati Cancer Institute has discovered a new approach to in vivo imaging of certain types of brain tumors, such as glioblastoma multiforme tumors, using biofluorescent markers and a multi-angle rotational optical imaging (MAROI) system. The fluorescent markers were applied to nanovesicles composed of the lysosomal protein saposin-C (SapC) with the phospholipid dioleoylphosphatidylserine (DOPS). This has been found to identify and kill certain brain cancer cell types, the researchers said. Fluorescent signal in an orthotopic brain tumor in a mouse model. Courtesy of Journal of Visualized Experiments. “We used SapC-DOPS as a transport vesicle to deliver biofluorescence agents and gadolinium-labeled contrast agents directly to brain tumors, which provided visualization using optical imaging and MRI,” said lead researcher Dr. Xiaoyang Qi, associate professor of hematology oncology at the University of Cincinnati. Kati LaSance, director of the university's Vontz Core Imaging Lab and a collaborator on this research, said enhanced tumor visualization could help physicians better determine proper treatment and potentially intervene earlier. “There are two things lacking when it comes to brain tumors: getting a good picture of them and treating them effectively,” LaSance said. “With this discovery, there are possibilities to improve both.” The labeled nanovesicles were studied via MAROI in both orthotopic and transgenic brain tumors in mice. Curve analysis of the multi-angle imaging determined the angle with the highest signal, which enabled the researchers to establish the optimal angle for imaging each disease site. The new technique can also target cancer cells in the lung, skin, prostate, blood and breast, all while sparing normal and healthy tissues, researcher said. The testing so far has been conducted on animals, but the researchers said testing the technique on humans could begin soon. The work was funded by the Mayfield Education and Research Foundation, the New Drug State Key Project, the National Institutes of Health and the National Cancer Institute. The research is published in the Journal of Visualized Experiments (doi: 10.3791/51187) and the Journal of Magnetic Resonance Imaging (doi: 10.1002/jmri.24654). For more information, visit www.cincinnaticancercenter.org.