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YK-4-279 effectively antagonizes EWS-FLI1 induced leukemia in a transgenic mouse model
Tsion Zewdu Minas1, Jenny Han1, Tahereh Javaheri2
1Department of Oncology, Georgetown University Medical Center, Washington, DC, USA.
Abstract:
Ewing sarcoma is an aggressive tumor of bone and soft tissue affecting predominantly children and young adults. Tumor-specific chromosomal translocations create EWS-FLI1 and similar aberrant ETS fusion proteins that drive sarcoma development in patients. ETS family fusion proteins and over-expressed ETS proteins are also found in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) patients. Transgenic expression of EWS-FLI1 in mice promotes high penetrance erythroid leukemia with dense hepatic and splenic infiltrations. We identified a small molecule, YK-4-279, that directly binds to EWS-FLI1 and inhibits its oncogenic activity in Ewing sarcoma cell lines and xenograft mouse models. Herein, we tested in vivo therapeutic efficacy and potential side effects of YK-4-279 in the transgenic mouse model with EWS-FLI1 induced leukemia. A two-week course of treatment with YK-4-279 significantly reduced white blood cell count, nucleated erythroblasts in the peripheral blood, splenomegaly, and hepatomegaly of erythroleukemic mice. YK-4-279 inhibited EWS-FLI1 target gene expression in neoplastic cells. Treated animals showed significantly better overall survival compared to control mice that rapidly succumbed to leukemia. YK-4-279 treated mice did not show overt toxicity in liver, spleen, or bone marrow. In conclusion, this in vivo study highlights the efficacy of YK-4-279 to treat EWS-FLI1 expressing neoplasms and support its therapeutic potential for patients with Ewing sarcoma and other ETS-driven malignancies.
Insights
A novel small molecule, YK-4-279, effectively treats EWS-FLI1-driven leukemia in mice. This compound reduced cancer cell growth and improved survival without significant toxicity, showing therapeutic potential for Ewing sarcoma and related cancers.
Area of Science:
- Oncology
- Molecular Biology
- Drug Discovery
Background:
- Ewing sarcoma is an aggressive pediatric cancer driven by EWS-FLI1 fusion proteins.
- EWS-FLI1 and other ETS fusions are implicated in various leukemias.
- YK-4-279 is a small molecule inhibitor of EWS-FLI1 oncogenic activity.
Purpose of the Study:
- To evaluate the in vivo therapeutic efficacy of YK-4-279.
- To assess potential side effects of YK-4-279 in a mouse model of EWS-FLI1-induced leukemia.
Main Methods:
- Treatment of transgenic mice with YK-4-279 for two weeks.
- Monitoring of hematological parameters, organomegaly, and survival.
- Analysis of EWS-FLI1 target gene expression and toxicity.
Main Results:
- YK-4-279 treatment significantly reduced white blood cell counts and erythroblasts.
- Splenomegaly and hepatomegaly were decreased in treated mice.
- Overall survival was significantly improved, with no overt signs of toxicity.
Conclusions:
- YK-4-279 demonstrates significant in vivo efficacy against EWS-FLI1-driven leukemia.
- The compound effectively inhibits oncogenic EWS-FLI1 activity and improves survival.
- YK-4-279 shows therapeutic promise for Ewing sarcoma and other ETS-driven malignancies.
