Detection of Brain Tumors and Systemic Metastases Using NanoLuc and Fluc for Dual Reporter Imaging

Purpose: Bioluminescence imaging (BLI) is a technique with a low background noise and high sensitivity which is widely used in mice models in oncology. We aimed to assess BLI efficiency of the new luciferase NanoLuc (Nluc) for glioblastoma cell lines and tumors, including for dual reporter applications of deep brain tumors and systemic metastasis when combined with firefly luciferase (Fluc). Procedures: U87 cells were genetically modified for constitutive production of either Nluc, Fluc, or both and assayed for luciferase activity and BLI on cell lysates, living cells, subcutaneous tumors, brain tumors, and systemic metastases. Results: In vitro, light production by Nluc activity is higher than Fluc. In vivo, Nluc allows for tumor detection including for deep brain tumors and systemic metastases. Conclusions: Nluc appears to be a useful tool to combine with Fluc for dual imaging in vivo using bioluminescence, allowing for the detection of distinct events in deep tissues within the same organism.