Inhibitory effect of nordihydroguaiaretic acid on β-catenin/Tcf signalling in β-catenin-activated cells.
Activated β-catenin/T-cell factor (Tcf) signalling plays a role in human carcinogenesis. We identified the inhibitory effect of nordihydroguaiaretic acid (NDGA) against β-catenin/Tcf signalling in β-catenin activated cells. NDGA inhibited the transcriptional activity of β-catenin/Tcf in HEK293 cells transiently transfected with a constitutively active mutant β-catenin gene. To investigate the inhibitory mechanism, electrophoresis mobility shift assay, immunoprecipitation and Western blot experiments were performed. The shift assay showed that the binding of Tcf complexes with its specific DNA-binding sites was suppressed by NDGA. Immunoprecipitation analysis also showed that the binding of β-catenin to Tcf-4 was also disrupted by NDGA. Western blot analysis showed a decreased level of β-catenin in nucleus caused by NDGA. NDGA did not decrease phosphorylation of Akt and GSK3β. Taken together, these results suggest that the NDGA acts as a negative regulator of β-catenin/Tcf signalling and its inhibitory mechanism is related to the decreased binding of β-catenin/Tcf complexes to consensus DNA.
Department of Applied Chemistry, Dongduk Women's University, Seoul, Korea. sypark21@dongduk.ac.kr
Seyeon
S
Park
Jihye
J
Lee
D060466:Axin Protein; D045744:Cell Line, Tumor; D019938:Cyclin D1 / Q000187:drug effects / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000187:drug effects / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay / Q000379:methods; D038362:Glycogen Synthase Kinase 3 / Q000187:drug effects / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D057809:HEK293 Cells; D006801:Humans; D009637:Masoprocol / Q000494:pharmacology*; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D051057:Proto-Oncogene Proteins c-akt / Q000187:drug effects / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D051820:TCF Transcription Factors / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D051176:beta Catenin / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*
C491761:AXIN2 protein, human; D060466:Axin Protein; D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; D016271:Proto-Oncogene Proteins c-myc; D051820:TCF Transcription Factors; D014157:Transcription Factors; D051176:beta Catenin; D019938:Cyclin D1; D009637:Masoprocol; C000605506:GSK3B protein, human; D000071679:Glycogen Synthase Kinase 3 beta; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3