Molecular imaging of tumor viability and metabolism in response to sorafenib treatment.

<p><b>A:</b> Images for representative mice bearing HCT116-luc2 tumors are shown that were imaged on day 9 by BLI to assess tumor burden/viability. Compared with vehicle control, HCT116-luc2 tumors treated with 120 mg/kg of sorafenib show significant quantitative reduction of BLI signal on day 9, indicating loss of tumor viability. (*<i>p</i> < 0.01, <i>n</i> = 15, student’s <i>t</i>-test, bar: s.e.m., representative of three independent studies) <b>B:</b> Images of tumor-bearing mice imaged using fluorescent BRS-680 and TfV-750. Both probes were administered IV on day 8 and the animals were imaged on day 9, allowing sufficient time to generate a tumor-specific fluorescent contrast. Compared with control tumors, the sorafenib treatment significantly reduced tumor metabolic activity on day 9. (^#<i>p</i> < 0.05, <i>n</i> = 5, Student’s <i>t</i>-test, bar: s.e.m., representative of three independent studies).