Figure 4

Quantifying decreased Collagen I ordering at the E0771 mammary tumor boundary in MMP13 KO mice. WT and MMP13 KO mice were implanted with E0771 mammary tumors as described, and images of anti-Collagen I immunofluorescence staining at the tumor-host interface were obtained as described in Figure 3. As described in Methods and Results, to quantitatively assess Collagen I ordering we calculated the mean coherency parameter averaged over all pixels in each image, thus producing a single coherency value for each image. This coherency value for each image was averaged for n=16 (WT) and n=14 (MMP13 KO) tumor boundary FOV images (± SEM) from the same cohort of animals to produce this plot. Mean coherency was significantly decreased in the MMP13 KO versus WT mice (*p < .007), reflecting less organized (more randomly oriented) collagen I structure. Coherency values for each image were produced using OrientationJ (http://bigwww.epfl.ch/demo/orientation/), then graphed in Kaleidagraph (Synergy Software, Reading, PA).