Fig. 2. FOXP3 inhibits breast cancer angiogenesis in vivo and in vitro.

a Orthotopic injection of MDA-MB-231 cells was performed to generate xenografts, and adenoviruses carrying FOXP3 or control cDNA were injected into the tumors when their volume reached approximately 50 mm³ (n = 5). Representative immunohistochemical images of FOXP3 and CD31 expression in the primary tumors of mice in the control and FOXP3 groups. Scale bars, 50 μm (×20) and 20 μm (×40). b Quantification of blood vessel density in (a). c Representative images of HUVEC tube formation assays; HUVECs were treated with control MDA-MB-231 cell supernatant or FOXP3-overexpressing MDA-MB-231 cell supernatant. Scale bar, 100 μm. d Quantitation of the cumulative number of tubes in the different groups in (c). e Representative images from the HUVEC spheroid sprouting assays; HUVECs were treated with control cell supernatant or FOXP3-overexpressing MDA-MB-231 cell supernatant. Scale bar, 100 μm. f Quantitation of the cumulative sprout length (CSL) of the different groups in (e). b, d, f Student’s t test