Identification of genes regulated by Wnt/beta-catenin pathway and involved in apoptosis via microarray analysis.
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.
Huang
Moli
M
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
Wang
Yihua
Y
Sun
Daochun
D
Zhu
Hongxia
H
Yin
Yanbing
Y
Zhang
Wei
W
Yang
Shangbin
S
Quan
Lanping
L
Bai
Jinfeng
J
Wang
Shengqi
S
Chen
Quan
Q
Li
Songgang
S
Xu
Ningzhi
N
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*
D051822:T Cell Transcription Factor 1; D051153:Wnt Proteins; D051176:beta Catenin