Transcriptional regulation of livin by beta-catenin/TCF signaling in human lung cancer cell lines.
Wnt/beta-catenin signaling emerged as a critical pathway in human lung carcinogenesis by regulating the livin promoter activity. This study clarified that livin was a direct target gene of beta-catenin/TCF signaling pathway in non-small cell lung cancer (NSCLC) cells. First, we observed that livin mRNA was up-regulated by LiCl treatment in culture of A549 and 103H cell lines. In addition we found that the activity of livin promoter is increased considerably by activation of beta-catenin and could be blocked by a dominant negative form of DeltaTCF4. Furthermore, we identified a TCF binding site located at -1476/-1470 of the livin promoter which is crucial to the response of beta-catenin. At last, chromatin immunoprecipitation (ChIP) assay was performed and the result indicated that beta-catenin/TCF complex binds to the putative TCF binding site of the livin promoter in A549 and 103H cell lines. Our results suggest that livin is transcriptionally regulated by beta-catenin/TCF signaling in human NSCLC cell lines.
Yuan
Dong
D
Department of Thoracic Surgery, The Affiliated Hospital of Weifang Medical College, Weifang, Shandong Province 261031, PR China. yuandong72@yahoo.com.cn
Liu
Liqun
L
Gu
Dayong
D
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics* / Q000378:metabolism; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D005786:Gene Expression Regulation; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000235:genetics* / Q000378:metabolism; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D051820:TCF Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D051176:beta Catenin / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; C419866:BIRC7 protein, human; D051034:Inhibitor of Apoptosis Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D051820:TCF Transcription Factors; D051176:beta Catenin