Extended Data 2. sFRP2 promotes invasion and angiogenesis.

Conditioned media from young fibroblasts treated with either control (PBS), or rsFRP2 (200ng/ml) was used to pre-treat WM793 melanoma cells for 48h. Invasion was assayed using a Boyden Chamber assay over 24–72h. Two-tailed unpaired t test was performed (p=0.033) (a). Conditioned media from aged fibroblasts treated with sFRP2 blocking antibody (15µg/ml) for 72h was used to pre-treat WM793 melanoma cells for 48h. The invasion of melanoma cells was assessed in a Boyden Chamber assay for 24–72h. Two-tailed unpaired t test was performed (p=0.035) (b). Young mice (8 weeks, 10 /group) were injected subcutaneously with Yumm1.7 cells. After palpable tumor appeared, mice were treated with rsFRP2 (200ng/mL) for 30 days and examined for angiogenesis using CD31 staining. Representative images, magnification 400× (c,d). Aged mice (52 weeks, n= 5 /group) were injected subcutaneously with Yumm1.7 cells and treated with either control IgG2aκ or sFRP2 blocking antibody (1mg/kg) for 3 weeks. Tumors were examined for angiogenesis by CD31 staining. Representative images, magnification 400× (e, f). Data are represented as mean ± s.d. for each graph (a,b).