human human cell in vitro study unclassified drug controlled study 78 Humans 68 nonhuman 51 priority journal 48 article 47 Animals 44 Article 42 in vivo study 34 metabolism 33 protein expression 28 animal experiment 27 mouse 27 Cell Line, Tumor 26 Mice 26 animal model 25 chemistry 25 male 24 animal cell 22 drug structure 22 animal 21 female 21 apoptosis 19 drug effects 18 Cell Line 16 Cell Proliferation 16 Male 16