medroxyprogesterone acetate article 52 mouse 50 nonhuman 50 Animals 46 Female 46 Mice 42 Mice, Inbred BALB C 42 female 40 priority journal 40 animal experiment 36 controlled study 34 animal cell 32 animal model 32 progesterone receptor 32 Mammary Neoplasms, Experimental 28 Medroxyprogesterone 17-Acetate 28 Receptors, Progesterone 28 protein expression 24 animal tissue 22 cell proliferation 22 Humans 20 breast adenocarcinoma 20 breast cancer 18 gestagen 18 protein phosphorylation 18 human 16 Adenocarcinoma 14 Breast Neoplasms 14 Progestins 14