Glucose-functionalized liposomes for reducing false positives in cancer diagnosis

Fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) is currently the most important functional imaging technique for the visualization of tumors by taking advantage of the increased glucose metabolic activity of cancer cells. However, 18F-FDG-PET imaging has high rates of false positives, as it cannot distinguish between tumor and inflammation regions that both features increased glucose metabolic activity. In this research, we engineered liposomes coated with glucose and the chelator dodecane tetraacetic acid (DOTA) complexed with copper, to serve as a diagnostic technology for differentiating between cancer and inflammation. This liposome technology is based on FDA-approved materials and enables complexation with metal cations and radionuclides. We found that these liposomes were preferentially uptaken by cancer cell lines with high metabolic activity, mediated via glucose transporter-1. In vivo, these liposomes were avidly uptaken by tumors, as compared to liposomes without glucose coating. Moreover, in a combined tumor-inflammation mouse model, these liposomes accumulated in the tumor tissue and not in the inflammation region. Thus, this technology shows high specificity for tumors while evading inflammation, and has potential for rapid translation to the clinic and integration with existing PET imaging systems, for effective reduction of false positives in cancer diagnosis.