Identification of SP5 as a downstream gene of the beta-catenin/Tcf pathway and its enhanced expression in human colon cancer

Int J Oncol. 2005 Dec;27(6):1483-7.


Mutations in APC, CTNNB1, AXIN1 or AXIN2 cause impairment in the beta-catenin degradation pathway and result in accumulation of beta-catenin in a wide range of human cancers. Accumulated beta-catenin then associates with Tcf/LEF transcription factors and transactivates their target genes. To uncover in detail the role of accumulated beta-catenin in colorectal carcinogenesis, we searched for genes involved in the beta-catenin/Tcf signaling pathway by cDNA microarray. We identified and characterized a human gene, SP5, that was down-regulated after depletion of beta-catenin by transduction of wild-type APC into SW480 cells. SP5 is a member of the Sp transcription factor family, which binds to the GC box or closely related sequences in promoters of many genes and control their expression. Reporter assays and an electromobility-shift assay revealed a DNA fragment between -285 and -279 in the 5' flanking region of this gene to be a target of the beta-catenin/Tcf4 complex. Our results indicate that SP5 is a novel direct down-stream target in the Wnt signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenomatous Polyposis Coli Protein / chemistry
  • Adenomatous Polyposis Coli Protein / genetics
  • Antibodies, Monoclonal / analysis
  • Binding Sites / genetics
  • Cell Line, Tumor
  • Colonic Neoplasms / genetics
  • Colonic Neoplasms / pathology
  • DNA-Binding Proteins
  • Electrophoretic Mobility Shift Assay
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic
  • HeLa Cells
  • Humans
  • Immunohistochemistry
  • Oligonucleotide Array Sequence Analysis
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • Signal Transduction / genetics
  • TCF Transcription Factors / genetics*
  • TCF Transcription Factors / metabolism
  • Transcription Factors / genetics*
  • Transcription Factors / immunology
  • Transcription Factors / metabolism
  • Transfection
  • beta Catenin / genetics*
  • beta Catenin / metabolism


  • Adenomatous Polyposis Coli Protein
  • Antibodies, Monoclonal
  • DNA-Binding Proteins
  • SP5 protein, human
  • TCF Transcription Factors
  • Transcription Factors
  • beta Catenin