Use of the hAR model to test the angiogenic potential of tumor cells. (A) Representative photograph of hARs cocultured with LNCaP STC for 30 days in basal medium (EBM-2 plus 10% FCS). The inset shows higher magnification of the same photograph. Scale bar represents 400 µm. (B) Representative micrographs of angiogenic outgrowth of hARs with or without LNCaP STCs for 25 days. Scale bar represents 400 µm. (C) Time course of angiogenic outgrowth length (normalized to day 25 of hARs alone) of hARs cultured with complete medium (EGM-2) with or without LNCaP STCs (shown in B). Values shown are mean ± SD of 3 independent experiments, each from 6 different umbilical cords (*P < .05 vs hARs alone; **P < .01; ***P < .001). (D) Branching density analysis in tumor hARs. Representative micrographs and quantifications of angiogenic outgrowth of hARs with or without LNCaP STCs for 25 days. Values shown are box-and-whisker plots of branching points number divided by sprout lengths and normalized to the median of hARs alone (*P < .05 vs hARs alone). (E) Dose-response normalized inhibitor curve fittings for evaluation of IC50 of Sunitinib treatment on hARs alone or with LNCaP STCs. Equation “log(inhibitor) vs normalized response” Y = 100/(1+10^((X-LogIC50))). Nonlinear regression R² > 0.7.