hepatoma cell article 20 human cell 18 priority journal 18 human 16 controlled study 14 5 aminolevulinate synthase 12 nonhuman 12 promoter region 12 Humans 10 Promoter Regions (Genetics) 10 RNA, Messenger 10 Transcription, Genetic 10 Transfection 10 chloramphenicol acetyltransferase 10 messenger RNA 10 5-Aminolevulinate Synthetase 8 Bioassay 8 Blotting, Western 8 Gene Deletion 8 Genes 8 Genes, Dominant 8 Genetic Vectors 8 Molecular mechanisms 8 Nuclear Proteins 8 RNA 8 Tumor Cells, Cultured 8 cyclic AMP responsive element 8 cyclic AMP responsive element binding protein 8 gene expression 8