As in human breast cancer, we found that FST was profoundly repressed in mammary tumors collected from transgenic mice expressing the Her2/Neu proto-oncogene in the mammary epithelia (MMTV-Neu) (Fig. 3a and b), as was Fstl3 (Additional file 9: Figure S8a) [34]. This evidence concerns the gene FSTL3 and breast cancer.