Estrogen-induced genes, WISP-2 and pS2, respond divergently to protein kinase pathway.
Recently, we identified WISP-2 (Wnt-1 inducible signaling pathway protein 2) as a novel estrogen-inducible gene in the MCF-7 human breast cancer cell line. In this study, we examined whether WISP-2 expression is modulated by PK activators. Treatment with protein kinase A (PKA) activators [cholera toxin plus 3-isobutyl-1-methylxanthine (CT/IBMX)] induced WISP-2 expression. CT/IBMX induced expression of the other estrogen-responsive gene, pS2, more dramatically than maximum stimulation by 17beta-estradiol (E2). Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA), which directly stimulates protein kinase C (PKC) activity, completely prevented WISP-2 mRNA induction by E2, whereas it increased pS2 mRNA expression more dramatically than maximum stimulation by E2. Results of treatments with the protein synthesis inhibitor cycloheximide and the pure antiestrogen ICI182,780 suggest that these PK pathways modulate WISP-2 gene expression via different molecular mechanisms than those for pS2. Because TPA inhibits cell proliferation, we investigated whether WISP-2 induction was dependent on cell growth. Cells were treated with insulin-like growth factor-1 (IGF-1) or interleukin-1alpha (IL-1alpha) to stimulate or inhibit cell growth, respectively. These treatments had no effect on WISP-2 mRNA expression either alone or in combination with E2, suggesting that WISP-2 induction is independent of cell growth.
Inadera
Hidekuni
H
Department of Public Health, Faculty of Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan. inadera@ma.toyama-mpu.ac.jp
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D055511:CCN Intercellular Signaling Proteins; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D002772:Cholera Toxin / Q000494:pharmacology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology; D020869:Gene Expression Profiling / Q000379:methods; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D036341:Intercellular Signaling Peptides and Proteins; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D011493:Protein Kinase C / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D000071163:Trefoil Factor-1; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D025521:Tumor Suppressor Proteins
D055511:CCN Intercellular Signaling Proteins; C413323:CCN5 protein, human; D036341:Intercellular Signaling Peptides and Proteins; D009363:Neoplasm Proteins; D011506:Proteins; D011960:Receptors, Estrogen; D012097:Repressor Proteins; C051838:TFF1 protein, human; D014157:Transcription Factors; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins; D004958:Estradiol; D002772:Cholera Toxin; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D015056:1-Methyl-3-isobutylxanthine