Fra-1: a novel target for retinoid action.
Using a cDNA gene expression array system, we identified fra-1 as a novel target molecule for retinoid action in the human pancreatic carcinoma cell line Dan-G. Retinoid treatment resulted in a significant and time-dependent induction of the fra-1 expression on the post-transcriptional level. Supershift assays revealed that fra-1 participates in the activator protein 1 complex together with c-fos, c-jun and junB. Transient transfection experiments using a reporter plasmid containing an activator protein site upstream of the CAT reporter gene revealed that the phorbolester-induced CAT activity was suppressed by retinoids. Since fra-1 lacks a transactivation function, we therefore suggest that the retinoid-mediated induction of fra-1 might function as a negative regulator of the activator protein 1 activity in human pancreatic carcinoma cells.
Kaiser
A
A
Medizinische Klinik mit Schwerpunkt Gastroenterologie/Hepatologie, Department of Gastroenterology, Klinikum Benjamin Franklin, Freie Universität Berlin, Germany.
Brembeck
F H
FH
v Marschall
Z
Z
Riecken
E O
EO
Wiedenmann
B
B
Rosewicz
S
S
D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics*; D012176:Retinoids / Q000378:metabolism* / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014212:Tretinoin / Q000378:metabolism / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D000099169:Fos-Related Antigen 1
D016760:Proto-Oncogene Proteins c-fos; D012176:Retinoids; D013755:Tetradecanoylphorbol Acetate; D018808:Transcription Factor AP-1; D014212:Tretinoin; D000099169:Fos-Related Antigen 1