Research article

Identification of genes regulated by Wnt/β-catenin pathway and involved in apoptosis via microarray analysis

Moli Huang^{* 1} , Yihua Wang^{* 2} , Daochun Sun³ , Hongxia Zhu² , Yanbing Yin¹ , Wei Zhang² , Shangbin Yang² , Lanping Quan² , Jinfeng Bai² , Shengqi Wang³ , Quan Chen⁴ , Songgang Li¹ and Ningzhi Xu²

¹Center of Bioinformatics, National Laboratory of Genetic Engineering and Protein Engineering, College of Life Sciences, Peking University, Beijing, P. R. China

²Laboratory of Cell and Molecular Biology, Cancer Institute & Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China

³No.9 lab, Beijing Institute of Radiation Medicine, Beijing, P. R. China

⁴The Laboratory of Apoptosis and Cancer Biology, The National Key Laboratory of Biomembrane and Membrane Biotechnology, The Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. China

author email corresponding author email* Contributed equally

BMC Cancer 2006, 6:221doi:10.1186/1471-2407-6-221

Published:	7 September 2006

Abstract

Background

Wnt/β-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/β-catenin pathway modification of the cellular apoptosis.

Methods

To identify potential genes regulated by Wnt/β-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 β-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 β-catenin expression and the transcriptional activity of β-catenin/TCF. Meanwhile, depletion of β-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-κB pathway and p53 pathway, showed significant alteration in their expression level after the knockdown of β-catenin.

Conclusion

Coupling RNAi knockdown with microarray and RT-PCR analyses proves to be a versatile strategy for identifying genes regulated by Wnt/β-catenin pathway and for a better understanding the role of this pathway in apoptosis. Some of the identified β-catenin/TCF directed or indirected target genes may represent excellent targets to limit tumor growth.