Wnt signaling via Beta-catenin plays a central role in development and homeostasis. This pathway is invariably disrupted in colorectal tumors and commonly affected by mutation in other cancers. Wnt ligand binding and activating the Frizzled transmembrane receptors transduced the signal to a cytoplasmic protein, known as disheveled protein, which then inhibits the serine/threonine kinase Glycogen Synthase-3 Beta (GSK-3B). This signal leads to functional inactivation and dissociation of a multi-protein Beta -catenin destruction comples, which is made up of the tumor suppressor protein Adenomatous Polyposis Coli (APC), GSK-3B and a scaffold of Axin. This results in dephosphorylation and dissociation of Beta -catenin. The unphosphorylated b-catenin is stabilized and accumulates in the cytoplasm of the cell. Beta -catenin then associates with the T-Cell Factor (TCF)/Lymphoid Enhancer Factor (LEF) family of transcription factors in the nucleus leading to transcription and expression of target genes, such as c-Myc, c-jun, Fra and cyclin D1. The CellSensor™ LEF/TCF-bla HCT-116 cell line contains a beta-lactamase reporter gene under control of the LEF/TCF stably integrated into HCT-116 cells. HCT-116 is a colon cancer cell line carrying a gain-of-function mutation in beta-catenin gene (deletion of amino acid Serine45), which prevents beta-catenin protein degradation leading to constitutive activation of downstream genes. Thus, this cell line constitutively expresses beta-lactamase, which may be further stimulated or inhibited, e.g., using Stealth RNAi™ siRNA. This cell line has also been tested under various experimental conditions, including DMSO concentration, cell number, stimulation time, and substrate loading time. Academic and non-profit customers, please inquire for special pricing.