Figure 4

Adrenomedullin did not affect tumor vascularization or osteoclastogenesis but increased tumor growth in the mammary fat pad. (A) and (B) show tumor vascularization. (A) Representative mammary fat pad tumor section stained for CD31. Arrows point to vessels with brown immunostaining (original magnification, ×640). (B) Quantification of CD31+ vessels in tumor. Fields containing stained vessels were counted per ×200 magnification field (two fields per tumor, four tumors per cell line). There was no significant difference between the groups. (C) Mammary fat pad growth. Two control (G8 and G26) and two adrenomedullin (AM)-overexpressing (A39 and A51) MDA-MB-231 clones were injected into the mammary fat pad of female athymic nude mice (n = 10 mice/cell line; n = 2 mammary fat pads/mouse). Data for two control clones (black squares) and the two AM-overexpressing clones (black triangles) were grouped together for the analysis. *P < 0.05, **P < 0.01, ***P < 0.001. (D) Osteoclast formation in vitro was unchanged by AM or 20–amino acid proadrenomedullin peptide (PAMP). D3 indicates the positive control, 1,25-dihydroxyvitamin D₃. TRAP+, Tartrate-resistant acid phosphatase–positive. MNC, Multinucleated cells.