Figure 4. Loss of Ets2 in stromal fibroblasts diminishes tumor growth in stromal Pten-deleted mammary glands.

(a) H&E sections of mammary glands after orthotopic injection of the ErbB2-expressing tumor cell line NT 2.5. T, tumor; str, stroma and scale bars represent 500 μm.

(b) Volumes of tumors collected 21 days after injection. Pten^loxP/loxP;Ets2^db/loxP (n=10) and Pten^loxP/loxP (n=10) control groups were combined ((*), n=20) after it was determined that there was no statistical difference in tumor incidence/load between these two control groups. Values represent the mean with s.d shown in parentheses.

(c) Sections from mammary glands with the indicated genotypes stained with the macrophage-specific marker F4/80. Scale bars represent 100 μm.

(d) Quantification of stromal cells positive for F4/80 in mammary glands. Values shown represent the mean with s.d.

(e) Frozen mammary gland sections stained with the endothelial-specific antibody, CD31. Scale bars represent 50 μm.

(f) Quantification of CD31 positive staining.

Bar values in Fig. 4d and 4f represent the mean and error bars represent s.d. For all the statistical analyses, an ANOVA model with Bonferroni adjustment was used. Pairwise comparisons shown have a significant difference between marked genetic groups.