Wnt-beta-catenin pathway signals metastasis-associated tumor cell phenotypes in triple negative breast cancers

• Type of Material: Article
• Authors: Pradip De, Avera Research Institute; Jennifer H. Carlson, Avera Research Institute; Hui Wu, Emory University; Adam Marcus, Emory University; Brian Leyland-Jones, Avera Research Institute; Nandini Dey, Avera Research Institute
• Language: English
• Date: 2016-07-12
• Publisher: Impact Journals
• Publication Version: Final Published Version
• Copyright Statement: © 2016 De et al.
• License: Creative Commons Attribution 3.0 Unported
• Final Published Version (URL): http://dx.doi.org/10.18632/oncotarget.8988
• Title of Journal or Parent Work: Oncotarget
• ISSN: 1949-2553
• Volume: 7
• Issue: 28
• Start Page: 43124
• End Page: 43149
• Grant/Funding Information: We acknowledge Avera Cancer Institute, Sioux Falls, SD for funding this study.
• Keywords: Life Sciences & Biomedicine; matrigel-invasion; EXPRESSION; PTEN LOSS; brain-metastasis specific TNBC cells; E-CADHERIN; integrin-directed migration; Wnt-pathway modulators; SULINDAC; DISEASE; Cell Biology; MOLECULAR TARGET; Oncology; ACTIVATION; PHASE-I; LWnt3ACM stimulation; Science & Technology; BRAIN METASTASIS; THERAPY
• Research Categories: Biology, Genetics; Health Sciences, Oncology; Biology, Cell

Abstract

Tumor cells acquire metastasis-associated (MA) phenotypes following genetic alterations in them which cause deregulation of different signaling pathways. Earlier, we reported that an upregulation of the Wnt-beta-catenin pathway (WP) is one of the genetic salient features of triple-negative breast cancer (TNBC), and WP signaling is associated with metastasis in TNBC. Using cBioPortal, here we found that collective % of alteration(s) in WP genes, CTNNB1, APC and DVL1 among breastinvasive- carcinomas was 21% as compared to 56% in PAM50 Basal. To understand the functional relevance of WP in the biology of heterogeneous/metastasizing TNBC cells, we undertook this comprehensive study using 15 cell lines in which we examined the role of WP in the context of integrin-dependent MA-phenotypes. Directional movement of tumor cells was observed by confocal immunofluorescence microscopy and quantitative confocal-video-microscopy while matrigel-invasion was studied by MMP7-specific casein-zymography. WntC59, XAV939, sulindac sulfide and beta-catenin siRNA (1) inhibited fibronectin-directed migration, (2) decreased podiaparameters and motility-descriptors, (3) altered filamentous-actin, (4) decreased matrigel-invasion and (5) inhibited cell proliferation as well as 3D clonogenic growth. Sulindac sulfide and beta-catenin siRNA decreased beta-catenin/active-beta-catenin and MMP7. LWnt3ACM-stimulated proliferation, clonogenicity, fibronection-directed migration and matrigel-invasion were perturbed by WP-modulators, sulindac sulfide and GDC-0941. We studied a direct involvement of WP in metastasis by stimulating brain-metastasis-specific MDA-MB231BR cells to demonstrate that LWnt3ACMstimulated proliferation, clonogenicity and migration were blocked following sulindac sulfide, GDC-0941 and beta-catenin knockdown. We present the first evidence showing a direct functional relationship between WP activation and integrin-dependent MAphenotypes. By proving the functional relationship between WP activation and MAphenotypes, our data mechanistically explains (1) why different components of WP are upregulated in TNBC, (2) how WP activation is associated with metastasis and (3) how integrin-dependent MA-phenotypes can be regulated by mitigating the WP.