Noninvasive in vivo whole body luminescent analysis of luciferase labelled orthotopic prostate tumours.

Light photons refracted through living tissues can be used to noninvasively monitor the proliferation of cells expressing bioluminescent markers. We demonstrate the use of a luminometer for noninvasive in vivo whole body luminometric analysis (in vivo WBLA) of luciferase-expressing prostate tumours growing orthotopically in nude mice, and thus hidden from visual inspection. In this procedure, the intraperitoneally (i.p.) inoculated luciferin, the luciferase substrate, reaches the tumours rapidly and the light photons generated by the tumour are recorded by placing the anaesthetised mice in the detection chamber of a luminometer, over the detector slot. We show that the number of recorded light photons is proportional to the tumour mass and to the luciferase activity recorded in vitro. The procedure is applied to demonstrate the use of paclitaxel as an antineoplasic agent with its well characterised antiproliferative activity.