Monitoring NF-kappaB mediated chemokine transcription in tumorigenesis.

Chemokine-receptor signaling plays an important role in the inflammatory response often associated with tumor growth and metastasis. The NF-kappaB pathway, essential for transcription of chemokines/chemokine receptors and other key inflammatory modulators, has emerged as a potential target for tumor therapy. Here we describe an efficient approach to monitor drugs that target the NF-kappaB signaling as related to tumor growth and metastasis in vivo. For bioluminescence imaging, the firefly luciferase (Fluc) reporter has the advantage of stable signaling, while Gaussia luciferase (Gluc) provides very sensitive signaling based on secretion of Gluc. We introduce the use of monitoring intratumoral Gluc, which rapidly diffuses into the blood circulation and urine. The peripheral Gluc assay may complement bioluminescence imaging and provide a kinetic, noninvasive, real-time read-out of NF-kappaB activity by directly determining Gluc reporter activity in blood or urine samples from tumor-bearing mice.