Regulation of gene expression by FOXC1 in mouse mammary epithelial cells.

The FOXC1 transcription factor plays a critical role in basal-like breast cancer development and metastasis. However, it is not clear whether its overexpression alters normal mammary development and mammary cell function in vivo. We used MMTV-FOXC1 transgenic mice to adddress this question. In association with the lobuloalveologenesis and lactation-related phenotype in the transgenic mice, we also found marked gene expression changes in mammary epithelial cells of the transgenic mice compared with wildtype mice at the lactation stage. Differentially expressed genes identified by RNA-Seq analysis include those involved in fatty acid metabolism, PPAR, cytokine, chemokine, inflammation, and NF-?B signaling. These data suggest that FOXC1 is an important regulator of mammary cell function. Overall design: Comparison of gene expression profiles in mammamry epithelial cells from MMTV-FOXC1 transgenic and wildtype mice at the lactation stage.