Figure 2

Immunohistochemical staining for metalloproteinase (MMP)-9 and α-smooth muscle actin (α-SMA) in mammary tumor sections. Tumors were resected from mice and double stained with antibodies to α-SMA to detect stromal cells (A) and MMP-9 (B). When channels were merged (C), these data show that MMP-9 was present in both stromal and tumor cells. Magnification 200×; scale bar is equivalent to 100 µm.