Metastatic melanoma is a highly lethal human malignancy. Despite advances in the field, the molecular genetics of melanoma has not been fully characterized. The Cancer Genome Atlas reports high mutational load for melanoma. Identification of 'driver' genes and novel therapeutics remain as a major focus. Notably, there is a need to classify melanomas based on molecular signatures that has therapeutic relevance. Our main goal is to bring in new treatments to the therapeutic arena for melanoma and stratify patients for treatment based on genetic profiles. We identified FBXW7 mutations as a novel genetic event via exome sequencing of metastatic melanomas. FBXW7 is a tumor suppressor gene that encodes a member of the F-box protein family. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination and regulates a network of proteins with central roles in cell division, cell growth and differentiation. The substrates of FBXW7 include well-characterized oncoproteins, one of which is NOTCH1. Screening of melanoma samples revealed missense and nonsense mutations in FBXW7, some of which were recurrent. We found that silencing of FBXW7 in human melanoma cell lines result in elevated NOTCH1 levels. Moreover, we showed that xenograft tumors with FBXW7 down regulation respond to NOTCH signaling inhibition. In this proposal, we aim to study the impact of FBXW7 mutations found in human melanoma and the therapeutic benefit of NOTCH1 inhibition in this setting. The studies in this proposal are designed to expand our knowledge regarding genetic events that influence melanoma development and metastasis with the goal of identifying novel targets for future mechanism-driven clinical trials. The ultimate goal of these studies is to translate knowledge gained from molecular studies into tools that can be used in clinical decision-making.

Public Health Relevance

There have been advances in understanding the genetic basis of melanoma, however these changes have not been fully defined. We identified mutations in FBXW7 tumor suppressor in melanoma as a novel genetic event. This proposal explores the role of FBXW7 in melanoma and brings in a new treatment for this deadly cancer.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21CA177940-02
Application #
8883428
Study Section
Special Emphasis Panel (ZCA1)
Program Officer
Sharman, Anu
Project Start
2014-07-01
Project End
2017-06-30
Budget Start
2015-07-01
Budget End
2017-06-30
Support Year
2
Fiscal Year
2015
Total Cost
Indirect Cost
Name
Icahn School of Medicine at Mount Sinai
Department
Pathology
Type
Schools of Medicine
DUNS #
078861598
City
New York
State
NY
Country
United States
Zip Code
10029
Abbate, Franco; Badal, Brateil; Mendelson, Karen et al. (2018) FBXW7 regulates a mitochondrial transcription program by modulating MITF. Pigment Cell Melanoma Res :
Aydin, Iraz T; Abbate, Franco; Rajan, Geena Susan et al. (2017) FBXW7 inactivation in a BrafV600E -driven mouse model leads to melanoma development. Pigment Cell Melanoma Res 30:571-574
Badal, Brateil; Solovyov, Alexander; Di Cecilia, Serena et al. (2017) Transcriptional dissection of melanoma identifies a high-risk subtype underlying TP53 family genes and epigenome deregulation. JCI Insight 2:
Aydin, Iraz T; Melamed, Rachel D; Adams, Sarah J et al. (2014) FBXW7 mutations in melanoma and a new therapeutic paradigm. J Natl Cancer Inst 106:dju107