Tumor-associated chromosomal translocations frequently result in the expression of chimeric fusion proteins that behave as aberrant transcription factors. These fusions can act as dominant oncoproteins that are necessary for the formation and maintenance of specific human cancers. EWS/ETS fusions consist of the N-terminus of EWS juxtaposed to the C-terminus of one of five ETS transcription factors, is found in Ewing's family tumors (EFTs). We have found that though both EWS/FLI1 and normal FLU can bind the same genomic loci in vivo, EWS/FLI1 modulates the expression of adjacent genes while normal FLU doesnot. Future rational strategies aimed at inhibiting EWS/ETS fusions depend on elucidating molecular mechanisms through which these proteins modulate target gene expression in comparison to normal ETS counterparts. To address this need the following studies will be performed: (i) relevant cell hosts to study EWS/ETS interactions will be characterized using human EFT derived cell lines and murine embryonal stem (ES) technologies;(ii) EWS/ETS direct target genes whose promoters are bound by three different EWS/ETS proteins will be identified by coupling ChlP/Chip experiments with microarray expression analyses;(iii) transcriptional processes that are modulated by EWS/FLI1 at direct target genes will be investigated. Many human cancers harbor specific mutations in their DMAthat result in the expression of aberrant proteins. In many cases, these proteins play major roles in the genesis and maintenance of these tumors. Antagonizing these abnormal proteins can profoundly inhibit tumor growth. In this proposal we focus on one such abnormal protein, EWS/FLI1, which is found in a subset of highly malignant pediatric cancers. Our goal is that by investigating the molecular mechanisms through which EWS/FLI1 promotes cancer, potent anti- cancer strategies will come to light.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA087771-10
Application #
7749534
Study Section
Special Emphasis Panel (ZRG1-ONC-P (02))
Program Officer
Mietz, Judy
Project Start
2000-07-01
Project End
2012-06-30
Budget Start
2010-03-10
Budget End
2012-06-30
Support Year
10
Fiscal Year
2010
Total Cost
$297,714
Indirect Cost
Name
University of California Los Angeles
Department
Pediatrics
Type
Schools of Medicine
DUNS #
092530369
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
France, Kelly A; Anderson, Jennifer L; Park, Ann et al. (2011) Oncogenic fusion protein EWS/FLI1 down-regulates gene expression by both transcriptional and posttranscriptional mechanisms. J Biol Chem 286:22750-7
Ikeda, Alan K; Judelson, Dejah R; Federman, Noah et al. (2010) ABT-869 inhibits the proliferation of Ewing Sarcoma cells and suppresses platelet-derived growth factor receptor beta and c-KIT signaling pathways. Mol Cancer Ther 9:653-60
Potikyan, Gary; France, Kelly A; Carlson, Marc R J et al. (2008) Genetically defined EWS/FLI1 model system suggests mesenchymal origin of Ewing's family tumors. Lab Invest 88:1291-302
Ng, King Pan; Potikyan, Gary; Savene, Rupert O V et al. (2007) Multiple aromatic side chains within a disordered structure are critical for transcription and transforming activity of EWS family oncoproteins. Proc Natl Acad Sci U S A 104:479-84
Deneen, Benjamin; Hamidi, Habib; Denny, Christopher T (2003) Functional analysis of the EWS/ETS target gene uridine phosphorylase. Cancer Res 63:4268-74
Deneen, Benjamin; Welford, Scott M; Ho, Thu et al. (2003) PIM3 proto-oncogene kinase is a common transcriptional target of divergent EWS/ETS oncoproteins. Mol Cell Biol 23:3897-908
Welford, S M; Hebert, S P; Deneen, B et al. (2001) DNA binding domain-independent pathways are involved in EWS/FLI1-mediated oncogenesis. J Biol Chem 276:41977-84
Deneen, B; Denny, C T (2001) Loss of p16 pathways stabilizes EWS/FLI1 expression and complements EWS/FLI1 mediated transformation. Oncogene 20:6731-41