human 81 human cell male protein expression controlled study 79 Humans 61 nonhuman 57 priority journal 56 article 55 Male 50 animal experiment 42 Animals 39 mouse 38 animal cell 35 animal model 33 female 33 Mice 30 human tissue 29 adult 28 Article 26 unclassified drug 26 Female 25 Cell Line, Tumor 24 cell proliferation 24 in vitro study 23 in vivo study 23 apoptosis 22 animal tissue 21 Aged 20 Middle Aged 20