Regulation of fibronectin gene expression by cyclic AMP and phorbol myristate acetate in HT-1080 human fibrosarcoma cells.
We studied the regulation of fibronectin (FN) gene expression by cAMP and phorbol-12-myristate-13-acetate (PMA) in HT-1080 human fibrosarcoma cells. Dibutyryl cAMP increased FN synthesis and mRNA levels, while PMA inhibited the cAMP-induced FN synthesis. In transient transfection assays, cAMP increased FN promoter activity, while PMA paradoxically enhanced the cAMP-induced promoter activity. Stable transfection experiments, however, showed that neither cAMP or PMA alone nor together affected FN promoter activity. These results suggest that PMA antagonizes the cAMP-induced FN gene expression and that both the action of cAMP and the inhibition of its action by PMA may occur at the posttranscriptional level in HT-1080 cells.
Lee
B H
BH
Department of Biochemistry, School of Medicine, Dongguk University, Kyungju, Korea.
Park
R W
RW
Kim
I S
IS
D015152:Blotting, Northern; D003994:Bucladesine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D005353:Fibronectins / Q000235:genetics* / Q000378:metabolism; D005354:Fibrosarcoma / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014162:Transfection; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000378:metabolism
D005353:Fibronectins; D012333:RNA, Messenger; D003994:Bucladesine; D008156:Luciferases; D001616:beta-Galactosidase; D013755:Tetradecanoylphorbol Acetate