article breast cancer 110 Female 80 controlled study 80 human 78 nonhuman 74 priority journal 72 female 70 Mice 64 mouse 64 human cell 62 Animals 60 Breast Neoplasms 58 Humans 58 animal cell 48 Mice, Inbred BALB C 46 animal model 44 animal experiment 42 cell proliferation 42 protein expression 42 Mammary Neoplasms, Experimental 36 progesterone receptor 34 unclassified drug 34 Receptors, Progesterone 32 animal tissue 32 cancer cell culture 28 Cell Proliferation 26 cancer cell 26 medroxyprogesterone acetate 24 Breast cancer 22