The overall objectives of this research are to investigate mechanisms of non-canonical Wnt signaling acting via Dishevelled (Dvl) protein, and to test the hypothesis that this pathway regulates cancer cell invasion and is relevant to malignant breast cancer. The canonical Wnt/?-catenin pathway contributes to the initiation of many cancers but recent evidence indicates that ?-catenin-independent, or non-canonical, Wnt signaling is relevant to later stages of malignant progression. This pathway also plays crucial roles in cell polarity and morphogenesis. Wnt-induced phosphorylation of Dvl provides a reliable assay for non-canonical Wnt signaling and a starting point for molecular dissection of the non-canonical pathway and its functions in malignancy. The functional significance of Dvl phosphorylation in Wnt signaling will be investigated by testing the properties of Dvl mutants that are resistant to Wnt-induced phosphorylation. We will also test the hypothesis that non-canonical Wnt signaling inhibits the invasion of ER-negative breast cancer cells. This will be achieved by in vitro assays of cell migration and invasion, in conjunction with signaling assays. The role of Dvl phosphorylation in cell migration will be explored, and we will identify downstream components of non-canonical Wnt signaling that are activated in this context. In view of the key role of Dvl protein in mediating and modulating Wnt signaling, a comprehensive analysis of changes in the subcellular distribution of Dvl in response to non-canonical Wnt signals will be performed by confocal microscopy. A proteomics approach will be taken to identify key changes in the proteins with which Dvl interacts as a result of non-canonical Wnt signals. In addition, transgenic mice will be generated in which non-canonical Wnt signaling will be activated in the mammary gland in a regulated manner. Effects of this signaling on mammary development will be determined and the mice will be crossed with existing mouse models of breast cancer to test directly the consequences of non-canonical Wnt signaling in tumor progression towards invasive and metastatic cancer. Since there is extensive evidence of aberrant Wnt expression in cancer, and most Wnt proteins can elicit non-canonical signals, it is likely that this poorly understood pathway of non-canonical Wnt signaling may be of widespread medical significance. Characterization of the molecular mechanisms involved will provide opportunities for manipulating the pathway for therapeutic purposes. ? ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA123238-01A1
Application #
7262833
Study Section
Tumor Cell Biology Study Section (TCB)
Program Officer
Woodhouse, Elizabeth
Project Start
2007-08-08
Project End
2011-07-31
Budget Start
2007-08-08
Budget End
2008-07-31
Support Year
1
Fiscal Year
2007
Total Cost
$311,448
Indirect Cost
Name
Weill Medical College of Cornell University
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
060217502
City
New York
State
NY
Country
United States
Zip Code
10065
Dass, Randall A; Sarshad, Aishe A; Carson, Brittany B et al. (2016) Wnt5a Signals through DVL1 to Repress Ribosomal DNA Transcription by RNA Polymerase I. PLoS Genet 12:e1006217
Zhao, S; Kurenbekova, L; Gao, Y et al. (2015) NKD2, a negative regulator of Wnt signaling, suppresses tumor growth and metastasis in osteosarcoma. Oncogene 34:5069-79
Many, Alexander M; Brown, Anthony M C (2014) Both canonical and non-canonical Wnt signaling independently promote stem cell growth in mammospheres. PLoS One 9:e101800
Gray, Jason D; Kholmanskikh, Stanislav; Castaldo, Bozena S et al. (2013) LRP6 exerts non-canonical effects on Wnt signaling during neural tube closure. Hum Mol Genet 22:4267-81
Stadler, Sonja C; Vincent, C Theresa; Fedorov, Victor D et al. (2013) Dysregulation of PAD4-mediated citrullination of nuclear GSK3? activates TGF-? signaling and induces epithelial-to-mesenchymal transition in breast cancer cells. Proc Natl Acad Sci U S A 110:11851-6
Santiago, Francisco; Oguma, Junya; Brown, Anthony M C et al. (2012) Noncanonical Wnt signaling promotes osteoclast differentiation and is facilitated by the human immunodeficiency virus protease inhibitor ritonavir. Biochem Biophys Res Commun 417:223-30
Gonsalves, Foster C; Klein, Keren; Carson, Brittany B et al. (2011) An RNAi-based chemical genetic screen identifies three small-molecule inhibitors of the Wnt/wingless signaling pathway. Proc Natl Acad Sci U S A 108:5954-63
Many, Alexander M; Brown, Anthony M C (2010) Mammary stem cells and cancer: roles of Wnt signaling in plain view. Breast Cancer Res 12:313
Takigawa, Yutaka; Brown, Anthony M C (2008) Wnt signaling in liver cancer. Curr Drug Targets 9:1013-24