The Epstein Barr Virus (EBV) is an oncogenic gamma-herpesvirus that is associated with Hodgkin disease and anaplasmic nasopharyngeal carcinoma. EBV infection is particularly hazardous with advanced HIV disease or transplant, where EBV-encoded proteins drive aberrant cell growth in the absence of immune surveillance. The principal EBV oncogene, Latent Membrane Protein 1 (LMP1), promotes cell survival and proliferation by mimicking activated immune receptors. Through incompletely defined pathways, LMP1 potently stimulates Nuclear Factor Kappa B (NF-kB), transcription factors that control inflammation, cell survival and growth. EBV- transformed cells rely on constitutive NF-kB activation, and rapidly undergo apoptosis upon NF-kB blockade. Side-effects preclude the clinical use of currently available NF-kB inhibitors, though LMP1-selective drug targets may afford substantially less toxicity. It is therefore important to define how LMP1 activates NF-kB. I have carried out a human genome-wide siRNA screen for cellular modulators of LMP1 canonical NF-kB activation. Hits that either suppress or enhance LMP1 activation of NF-kB have been validated with secondary screens. The screens have implicated numerous proteins in LMP1 function, including novel factors not previously associated with NF-kB. I will carry out hypothesis-based and larger-scale secondary assays to identify critical missing components of LMP1 NF-kB activation in both epithelial cells and B lymphoblasts. I will pursue detailed biochemical analysis of several targets of particular interest, including potentially druggable enzymes and functionally clustered hits. Secondary screens will further stratify hits into functional groups based on whether they affect LMP1 expression, subcellular trafficking, and where they function within the LMP1/NF-kB pathway. Cellular factors uniquely employed by LMP1, but not by immune receptor pathways, may serve as important therapeutic targets for treatment of EBV-driven malignancies. Likewise, these studies may reveal important general mechanisms of NF-kB activation, with implications for allergy, autoimmunity, and host-defense.

Public Health Relevance

Persistent Epstein Barr virus infection is an important cause of certain lymphoma and throat cancers. This project will better define how EBV subverts cellular machinery to drive cancerous growth of infected cells. Ultimately, it is hoped that knowledge gained from these studies may enable the development of chemotherapies that specifically block EBV function.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Clinical Investigator Award (CIA) (K08)
Project #
5K08CA140780-03
Application #
8284169
Study Section
Subcommittee G - Education (NCI)
Program Officer
Jakowlew, Sonia B
Project Start
2010-07-01
Project End
2015-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
3
Fiscal Year
2012
Total Cost
$179,910
Indirect Cost
$13,327
Name
Brigham and Women's Hospital
Department
Type
DUNS #
030811269
City
Boston
State
MA
Country
United States
Zip Code
02115
Hunter, J E; Butterworth, J A; Zhao, B et al. (2016) The NF-κB subunit c-Rel regulates Bach2 tumour suppressor expression in B-cell lymphoma. Oncogene 35:3476-84
Greenfeld, Hannah; Takasaki, Kaoru; Walsh, Michael J et al. (2015) TRAF1 Coordinates Polyubiquitin Signaling to Enhance Epstein-Barr Virus LMP1-Mediated Growth and Survival Pathway Activation. PLoS Pathog 11:e1004890
Zhou, Hufeng; Schmidt, Stefanie C S; Jiang, Sizun et al. (2015) Epstein-Barr virus oncoprotein super-enhancers control B cell growth. Cell Host Microbe 17:205-16
Minamitani, Takeharu; Yasui, Teruhito; Ma, Yijie et al. (2015) Evasion of affinity-based selection in germinal centers by Epstein-Barr virus LMP2A. Proc Natl Acad Sci U S A 112:11612-7
Zhao, Bo; Barrera, Luis A; Ersing, Ina et al. (2014) The NF-κB genomic landscape in lymphoblastoid B cells. Cell Rep 8:1595-606
Iannetti, Alessio; Ledoux, Adeline C; Tudhope, Susan J et al. (2014) Regulation of p53 and Rb links the alternative NF-κB pathway to EZH2 expression and cell senescence. PLoS Genet 10:e1004642
Zhou, Xiaohui; Massol, Ramiro H; Nakamura, Fumihiko et al. (2014) Remodeling of the intestinal brush border underlies adhesion and virulence of an enteric pathogen. MBio 5:
Ersing, Ina; Bernhardt, Katharina; Gewurz, Benjamin E (2013) NF-κB and IRF7 pathway activation by Epstein-Barr virus Latent Membrane Protein 1. Viruses 5:1587-606
Zhou, Xiaohui; Gewurz, Benjamin E; Ritchie, Jennifer M et al. (2013) A Vibrio parahaemolyticus T3SS effector mediates pathogenesis by independently enabling intestinal colonization and inhibiting TAK1 activation. Cell Rep 3:1690-702
Gewurz, Benjamin E; Towfic, Fadi; Mar, Jessica C et al. (2012) Genome-wide siRNA screen for mediators of NF-κB activation. Proc Natl Acad Sci U S A 109:2467-72

Showing the most recent 10 out of 11 publications