Female article controlled study female protein expression Animals Humans Mice Mice, Inbred BALB C animal cell animal experiment mouse nonhuman priority journal signal transduction Breast Neoplasms Epithelial Cells Receptors, Progesterone animal model animal tissue breast adenocarcinoma breast cancer cancer cell cell proliferation medroxyprogesterone acetate protein phosphorylation protein targeting steroid receptor Active Transport, Cell Nucleus Antineoplastic Agents, Hormonal