title: Identification of genes regulated by Wnt/beta-catenin pathway and involved in apoptosis via microarray analysis.
abstract: BACKGROUND
  Wnt/beta-catenin pathway has critical roles in development and oncogenesis. Although significant progress has been made in understanding the downstream signaling cascade of this pathway, little is known regarding Wnt/beta-catenin pathway modification of the cellular apoptosis.
  
  
  METHODS
  To identify potential genes regulated by Wnt/beta-catenin pathway and involved in apoptosis, we used a stably integrated, inducible RNA interference (RNAi) vector to specific inhibit the expression and the transcriptional activity of beta-catenin in HeLa cells. Meanwhile, we designed an oligonucleotide microarray covering 1384 apoptosis-related genes. Using oligonucleotide microarrays, a series of differential expression of genes was identified and further confirmed by RT-PCR.
  
  
  RESULTS
  Stably integrated inducible RNAi vector could effectively suppress beta-catenin expression and the transcriptional activity of beta-catenin/TCF. Meanwhile, depletion of beta-catenin in this manner made the cells more sensitive to apoptosis. 130 genes involved in some important cell-apoptotic pathways, such as PTEN-PI3K-AKT pathway, NF-kappaB pathway and p53 pathway, showed significant alteration in their expression level after the knockdown of beta-catenin.
  
  
  CONCLUSIONS
  Coupling RNAi knockdown with microarray and RT-PCR analyses proves to be a versatile strategy for identifying genes regulated by Wnt/beta-catenin pathway and for a better understanding the role of this pathway in apoptosis. Some of the identified beta-catenin/TCF directed or indirected target genes may represent excellent targets to limit tumor growth.
authors.affiliation: Center of Bioinformatics, National Laboratory of Genetic Engineering and Protein Engineering, College of Life Sciences, Peking University, Beijing, PR China. huangml@mail.cbi.pku.edu.cn
authors.forename: Moli
authors.initials: M
authors.lastname: Huang
authors.forename: Yihua
authors.initials: Y
authors.lastname: Wang
authors.forename: Daochun
authors.initials: D
authors.lastname: Sun
authors.forename: Hongxia
authors.initials: H
authors.lastname: Zhu
authors.forename: Yanbing
authors.initials: Y
authors.lastname: Yin
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Shangbin
authors.initials: S
authors.lastname: Yang
authors.forename: Lanping
authors.initials: L
authors.lastname: Quan
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Bai
authors.forename: Shengqi
authors.initials: S
authors.lastname: Wang
authors.forename: Quan
authors.initials: Q
authors.lastname: Chen
authors.forename: Songgang
authors.initials: S
authors.lastname: Li
authors.forename: Ningzhi
authors.initials: N
authors.lastname: Xu
mesh_terms: D017209:Apoptosis / Q000235:genetics*; D016000:Cluster Analysis; D015536:Down-Regulation; D006367:HeLa Cells; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D034622:RNA Interference / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics; D051822:T Cell Transcription Factor 1 / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection / Q000379:methods; D051153:Wnt Proteins / Q000378:metabolism* / Q000502:physiology*; D051176:beta Catenin / Q000378:metabolism* / Q000502:physiology*
chemical_list: D051822:T Cell Transcription Factor 1; D051153:Wnt Proteins; D051176:beta Catenin