A High-Content Imaging Screen for Cellular Regulators of β-Catenin Protein Abundance. (March 2016)

• Record Type: Journal Article
• Authors: Zeng, Xin; Montoute, Monica; Bee, Tiger W.; Lin, Hong; Kallal, Lorena A.; Liu, Yan; Agarwal, Pankaj; Wang, Dayuan; Lu, Quinn; Morrow, Dwight; Pope, Andrew J.; Wu, Zining
• Is Part Of: Journal of biomolecular screening. Volume 21:Number 3(2016)
• Page Start: 260
• Page End: 268
• Publication Date: 2016-03
• Subjects: β-catenin -- colon cancer -- high-content imaging -- adenomatous polyposis coli (APC) -- tankyrase (TNKS) -- Wnt; Drugs -- Analysis -- Periodicals; Drugs -- Testing -- Periodicals; Biomolecules -- Analysis -- Periodicals; 572.36
• DOI: 10.1177/1087057115620169
• Languages: English
• ISSNs: 1087-0571

Abstract

Abnormal accumulation of β-catenin protein, a key transcriptional activator required for Wnt signaling, is the hallmark of many tumor types, including colon cancer. In normal cells, β-catenin protein level is tightly controlled by a multiprotein complex through the proteosome pathway. Mutations in the components of the β-catenin degradation complex, such as adenomatous polyposis coli (APC) and Axin, lead to β-catenin stabilization and the constitutive activation of target genes. Since the signal transduction of Wnt/β-catenin is mainly mediated by protein–protein interactions, this pathway has been particularly refractory to conventional target-based small-molecule screening. Here we designed a cellular high-content imaging assay to detect β-catenin protein through immunofluorescent staining in the SW480 colon cancer cell line, which has elevated β-catenin endogenously. We demonstrate that the assay is robust and specific to screen a focused biologically diverse chemical library set against known targets that play diverse cellular functions. We identified a number of hits that reduce β-catenin levels without causing cell death. These hits may serve as tools to understand the dynamics of β-catenin degradation. This study demonstrates that detecting cell-based β-catenin protein stability is a viable approach to identifying novel mechanisms of β-catenin regulation as well as small molecules of therapeutic potential.