Imaging of NTR activity in cells and in <i>in vivo</i> cancer model with NCL.

<p>(A) Concentration-dependent uncaging of NCL in MDA-MB-231 NTR+luc+ cancer cells in comparison with luciferin. (B) Selectivity of NTR imaging by NCL in the same cells in comparison with NTR-luc+ cells. The dashed line indicates background (cells only), *P = 0.0001. (C) <i>In vivo</i> imaging of NTR activity in subcutaneous NTR+ and NTR- xenografts (n = 5). Total luminescence over 1 h from IP injection of luciferin (1.5 mg) and NCL (1.9 mg). d) Representative images of mice 15 min post injection of luciferin or NCL.</p>