Wnt/β-catenin and EGFR pathways are important in cancer development and often aberrantly activated in human cancer.
However, it is very important to understand the mechanism responsible for this activation and the relation between them. Here, we report the mechanism of EGFR expression by transcriptionally active β-catenin in GSK3β-inactivated prostate cancer cells that eventually leads to its enhanced proliferation and survival. Expressions of β-catenin and EGFR are elevated in various cancers specifically in prostate cancer cells, DU145. When GSK3β is inactivated in these cells, β-catenin gets stabilized, phosphorylated at Ser-552 by protein kinase A, accumulates in the nucleus, and regulates the expression of its target genes that include EGFR. Chromatin immunoprecipitation (ChIP) and promoter analysis revealed that the EGFR promoter gets occupied by transcriptionally active β-catenin when elevated in GSK3β-inactivated cells. This phenomenon not only leads to increased expression of EGFR but also initiates the activation of its downstream molecules such as ERK1/2 and Stat3, ultimately resulting in up-regulation of multiple genes involved in cell proliferation and survival.
Written by:
Guturi KK, Mandal T, Chatterjee A, Sarkar M, Bhattacharya S, Chatterjee U, Ghosh MK. Are you the author?
Signal Transduction in Cancer and Stem Cells Laboratory, Council of Scientific and Industrial Research-Indian Institute of Chemical Biology, 4 Raja Subodh Chandra Mullick Road, Kolkata 700032, West Bengal, India.
Reference: J Biol Chem. 2012 May 25;287(22):18287-96.
doi: 10.1074/jbc.M111.324798
PubMed Abstract
PMID: 22493441