Figure 7.

Smooth muscle invasion is prevented by expression of uncleavable α6 integrin mutant (DU145 α6AA). Prostate tumor cells (1 x 10⁷) expressing the α6 integrin (A, DU145 α6WT), not expressing the α6 integrin (B, DU145 α6KO) or a mutated and uncleavable α6 integrin (C, DU145 α6AA) were grown on the undersurface of the diaphragm in a mouse and harvested 8 weeks later. The resulting tissue sections are shown (A-C) stained with hematoxylin and eosin with the tumor (blue), the muscle surface (white dotted line), and the underlying muscle (pink). The number of invasion sites along a 4mm stretch of diaphragm and the maximum depth of invasion was measured using the images (D). The standard error of the median values is shown and compared using a two-way ANOVA analysis (***p<0.0001). Results are representative of at least 4 biological and technical replicates, n=36.