Gene Targets of C/EBP/Beta Involved in Mammary Gland Development and Breast Cancer

摘要

Previous analyses of C/EBP beta KO mice have demonstrated an important role for this transcription factor in early developmental events in the mammary gland. In the pre-pubescent mouse, progesterone receptor (PR) expression is uniform along the ducts, but becomes non-uniform following the completion of ductal morphogenesis. However, PR remained uniformly expressed in the C/EBP beta KO glands. Similar increases in prolactin receptor (PrIR) and estrogen receptor were also observed. When PR expression was examined in the PrIR KO gland, a uniform pattern of expression was also observed. In order to determine if these effects were epithelial cell autonomous and independent of any alterations in systemic hormone levels, PrIR KO and Stat5A/B double KO mammary glands were transplanted into the cleared fat pads of nude mice.