The goal of this application is to use the zebrafish to identify novel pathways that regulate stem cell self- renewal in both normal muscle and embryonal rhabdomyosarcoma (ERMS), a pediatric malignancy of muscle. The zebrafish, with its close synteny to the human genome and its conserved molecular pathways regulating the development of tissues and organs, offers a powerful tool with which to conduct such research. My hypothesis is that evolutionary conserved pathways regulate stem cell function in both normal satellite cells and cancer stem cells found in ERMS. In normal muscle, satellite cells divide asymmetrically producing a differentiated daughter cell and another satellite cell, ultimately allowing for the regeneration muscle fibers following injury. By contrast, activation of self-renewal pathways in cancer is often deleterious. For example, a subset of tumor cells are capable of producing differentiated cell types and yet retain the capacity for self-renewal. It is these cancer stem cells that must be targeted for destruction if patients are to remain tumor free following conventional chemotherapeutic and radiation treatments.
In Aim 1, normal and cancer stem cell populations will be identified within zebrafish muscle. Transgenic approaches that label normal muscle cell populations based on differentiation status have previously been established as has a robust zebrafish transgenic model of RAS-induced rhabdomyosarcoma that is molecularly similar to human disease. The stem cell populations in normal muscle and ERMS will be identified using these reagents and expression analysis of these cell populations will be performed to assess whether conserved genetic programs are associated with differentiation status and self-renewal in both cell types.
In Aim 2, the function of these evolutionary conserved gene factors will be interrogated, establishing a role for these genes in self- renewal of muscle stem cells. Specifically, a targeted genetic modifier screen will be performed to uncover regulators of self-renewal and stem cell number in ERMS. Further experiments will assess if these factors also regulate satellite cell number and function. The long-term goal of this application is to discover new genetic pathways that both increase normal satellite cells in the case of muscle degenerative disease or decrease self-renewal potential in cancer. Ultimately, a subset of these genetic modifiers of self-renewal may prove to be useful targets for small molecule intervention in the treatment of human disease.

National Institute of Health (NIH)
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Research Scientist Development Award - Research & Training (K01)
Project #
Application #
Study Section
Arthritis and Musculoskeletal and Skin Diseases Special Grants Review Committee (AMS)
Program Officer
Boyce, Amanda T
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Massachusetts General Hospital
United States
Zip Code
Chen, Eleanor Y; Dobrinski, Kimberly P; Brown, Kim H et al. (2013) Cross-species array comparative genomic hybridization identifies novel oncogenic events in zebrafish and human embryonal rhabdomyosarcoma. PLoS Genet 9:e1003727
Blackburn, Jessica S; Liu, Sali; Langenau, David M (2011) Quantifying the frequency of tumor-propagating cells using limiting dilution cell transplantation in syngeneic zebrafish. J Vis Exp :e2790
Hettmer, Simone; Liu, Jianing; Miller, Christine M et al. (2011) Sarcomas induced in discrete subsets of prospectively isolated skeletal muscle cells. Proc Natl Acad Sci U S A 108:20002-7
Sander, Jeffry D; Dahlborg, Elizabeth J; Goodwin, Mathew J et al. (2011) Selection-free zinc-finger-nuclease engineering by context-dependent assembly (CoDA). Nat Methods 8:67-9
Blackburn, Jessica S; Liu, Sali; Raimondi, Aubrey R et al. (2011) High-throughput imaging of adult fluorescent zebrafish with an LED fluorescence macroscope. Nat Protoc 6:229-41
Smith, Alexandra C H; Raimondi, Aubrey R; Salthouse, Chris D et al. (2010) High-throughput cell transplantation establishes that tumor-initiating cells are abundant in zebrafish T-cell acute lymphoblastic leukemia. Blood 115:3296-303
Feng, Hui; Stachura, David L; White, Richard M et al. (2010) T-lymphoblastic lymphoma cells express high levels of BCL2, S1P1, and ICAM1, leading to a blockade of tumor cell intravasation. Cancer Cell 18:353-66
Blackburn, Jessica S; Langenau, David M (2010) aMAZe-ing tools for mosaic analysis in zebrafish. Nat Methods 7:188-90
Ignatius, Myron S; Langenau, David M (2009) Zebrafish as a Model for Cancer Self-Renewal. Zebrafish :