Human lung and bladder carcinoma tumors as compared to their adjacent normal tissue have elevated AP-1 activity associated with the retinoblastoma gene promoter.
Examination of the nucleotide sequence of the retinoblastoma (Rb) promoter revealed the presence of a DNA region highly homologous to the recognition site for the cellular transcription factor AP-1. A pair of complementary oligonucleotides containing the AP-1 site was synthesized and used in gel retardation assays to determine the role of the AP-1 protein in the regulation of the Rb gene expression. Using nuclear extracts from Hela cells as well as from lung and bladder tumors, we found specific binding of the AP-1 protein to this oligonucleotide. This binding is elevated in Hela cells, in 10/13 lung and 3/8 bladder tumors as compared to adjacent normal tissue. These results suggest that AP-1 could be implicated in Rb gene transcriptional regulation through its interaction with the AP-1 binding site of the Rb gene promoter.
Linardopoulos
S
S
Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece.
Papadakis
E
E
Delakas
D
D
Theodosiou
V
V
Cranidis
A
A
Spandidos
D A
DA
D000906:Antibodies / Q000494:pharmacology; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D004273:DNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D016161:Genes, Retinoblastoma / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008168:Lung / Q000502:physiology*; D008175:Lung Neoplasms / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics*; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics* / Q000378:metabolism; D012680:Sensitivity and Specificity; D012689:Sequence Homology, Nucleic Acid; D001743:Urinary Bladder / Q000502:physiology*; D001749:Urinary Bladder Neoplasms / Q000235:genetics*
D000906:Antibodies; D002352:Carrier Proteins; D004273:DNA, Neoplasm; D016755:Proto-Oncogene Proteins c-jun