Approximately 15-20% of breast cancers have a triple negative phenotype (negative for ER and PR expression and lack ErbB2 overexpression) that correlates with aggressive cancer and limited treatment options. We have developed an in vivo screen for defining the role of specific kinases in tumorigenesis and metastasis of breast cancer cells. Triple negative and triple positive breast cancer lines were used for shRNA-mediated knock down of specific kinases. The genetically altered lines (expressing luciferase in addition to specific shRNA gene knockdown) are injected into the mammary fat pad of female SCID mice. Tumor growth and vascularization is monitored longitudinally over an 8 week period using a micro-probe ultrasound system. Metastasis is monitored by bioluminescence imaging. The assay provides an in vivo screen for analysis of proteins that control the growth, vascularization and metastasis of breast tumors. MAP3Ks are the first tier of kinases regulating the MAP kinase signaling pathways that lead to the activation of the MAPKs ERKl/2, p38, JNK and ERKS. MAPSKs control expression of genes important for regulating the cell cycle, cytokine and protease expression and apoptosis. In a screen of 9 MAP3Ks, MEKK2 was identified as a key regulator of metastasis using MDA-MB-231 (triple negative basal) and BT474 (triple positive luminal) breast adenocarcinoma cells in the in vivo tumorigenesis assay. MEKK2 is a MAP3K that regulates the activation of the JNK and ERK5 pathways via activation of MKK7 and MEKS. We have shown that MEKK2 expression is required for EGFR (ErbBI) and ErbB2/Neu activation of ERKS in MDA-MB-231 and BT474 cells, respectively. Our hypothesis is that the MAP3K MEKK2 functions as a critical signaling node within the cell signaling network stimulating tumor growth and metastasis in response to ErbB and possibly other tyrosine kinases. The goal of this proposal is to genetically define the role of MEKK2 in triple negative breast cancer tumor growth and metastasis and to develop a MEKK2 small molecule inhibitor.
Specific aim 1 involves defining the role of MEKK2-MEK5-ERK5 signaling in tumorigenesis and metastasis of triple negative breast cancer cells using the in vivo xenograft assay.
In specific aim 2, we propose to elucidate the mechanism by which MEKK2 gets activated by ErbB1/2 using MEKK2 mutants in biochemical and cell-based activation assays.
In specific aim 3, a small molecule biochemical screen will be developed to identify compounds that specifically inhibit MEKK2 kinase activity. MEKK2 inhibitors will be tested for MAPK pathway specificity in cell-based assays and profiled for specificity against the kinome. In future studies, these MEKK2 inhibitors will be tested for anti-tumor efficacy in genetically engineered mouse models (GEMMs) of breast cancer.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Specialized Center--Cooperative Agreements (U54)
Project #
Application #
Study Section
Special Emphasis Panel (ZCA1-SRLB-3 (O1))
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
North Carolina Central University
United States
Zip Code
Ahmad, Syed; St Hilaire, Valentine R; Dandepally, Srinivasa R et al. (2018) Discovery and characterization of an iminocoumarin scaffold as an inhibitor of MEKK2 (MAP3K2). Biochem Biophys Res Commun 496:205-211
Butler, EboneƩ N; Bensen, Jeannette T; Chen, Mengjie et al. (2018) Prediagnostic Smoking Is Associated with Binary and Quantitative Measures of ER Protein and ESR1 mRNA Expression in Breast Tumors. Cancer Epidemiol Biomarkers Prev 27:67-74
Des Marais, Andrea C; Zhao, Yuqian; Hobbs, Marcia M et al. (2018) Home Self-Collection by Mail to Test for Human Papillomavirus and Sexually Transmitted Infections. Obstet Gynecol 132:1412-1420
DeBono, Nathan L; Robinson, Whitney R; Lund, Jennifer L et al. (2018) Race, Menopausal Hormone Therapy, and Invasive Breast Cancer in the Carolina Breast Cancer Study. J Womens Health (Larchmt) 27:377-386
Ma, Shaohua; Paiboonrungruan, Chorlada; Yan, Tiansheng et al. (2018) Targeted therapy of esophageal squamous cell carcinoma: the NRF2 signaling pathway as target. Ann N Y Acad Sci 1434:164-172
Kienka, Tamina; Varga, Matthew G; Caves, Josie et al. (2018) Epstein-Barr virus, but not human cytomegalovirus, is associated with a high-grade human papillomavirus-associated cervical lesions among women in North Carolina. J Med Virol :
Kilfoyle, Kimberly A; Des Marais, Andrea C; Ngo, Mai Anh et al. (2018) Preference for Human Papillomavirus Self-Collection and Papanicolaou: Survey of Underscreened Women in North Carolina. J Low Genit Tract Dis 22:302-310
Xiong, Zhaohui; Ren, Shuang; Chen, Hao et al. (2018) PAX9 regulates squamous cell differentiation and carcinogenesis in the oro-oesophageal epithelium. J Pathol 244:164-175
Odera, Joab Otieno; Odera, Elizabeth; Githang'a, Jessie et al. (2017) Esophageal cancer in Kenya. Am J Dig Dis (Madison) 4:23-33
Zhao, Ming; Howard, Erin W; Parris, Amanda B et al. (2017) Alcohol promotes migration and invasion of triple-negative breast cancer cells through activation of p38 MAPK and JNK. Mol Carcinog 56:849-862

Showing the most recent 10 out of 72 publications