Fig. 3

Apigenin (API) reduces multiple metastases and prolongs survival in an experimental metastasis model with an intracardiac injection. a Timeline of the in vivo study design for investigating the antimetastatic activities of API. Male NSG mice were intracardially injected with luciferase-tagged PC-3 M cells (PC-3 M-Luc). Mice were pretreated with API (3 mg/kg, IP) or the vehicle for 3 days before the intracardiac injection which was then administered 6 days/week. Whole-body bioluminescent imaging (BLI) was performed at different time points after cell-injection in NSG mice. b All mice were sacrificed at 5 weeks after the intracardiac injection of PC-3 M-Luc cells, and luciferase activity was detected every week with an IVIS spectrum imaging system (right panel). Quantitative analysis of Xenogen imaging signal intensity (photons/s) every week (left panel). * p < 0.05, ** p < 0.01, *** p < 0.001 compared to the control group. c-h Ex vivo representative images of metastatic sites at the end of this metastasis assay in mice treated with API (3 mg/kg, IP) or the vehicle (upper panel). Liver (c), pancreas (d), lungs (e), bone (f), spinal cord (g), and brain (h) are major organs for metastasis. Signal intensities from these metastatic organs were bioluminescently captured at the end of the study, with the mean signal for each group indicated (lower panel). * p < 0.05, ** p < 0.01, *** p < 0.001 compared to the control group. i Kaplan-Meier survival curves for control and apigenin (3 mg/kg)-treated mice. p values were analyzed by the log-rank test