Rhabdomyosarcoma xenotransplants in zebrafish embryos.

Area of Science:

• Oncology
• Developmental Biology
• Pharmacology

Background:

• Rhabdomyosarcomas (RMS) are the most common pediatric soft tissue sarcomas.
• High-risk and metastatic RMS have a poor prognosis, necessitating improved therapeutic strategies.
• Current model systems for drug development are limited in speed, cost-efficiency, and recapitulation of human disease.

Purpose of the Study:

• To develop a novel, rapid, and cost-efficient zebrafish xenotransplant model for rhabdomyosarcoma (RMS) drug screening.
• To evaluate the efficacy of established and novel therapeutic agents in this new preclinical model.
• To facilitate drug development and personalized medicine approaches for pediatric RMS.

Main Methods:

• Establishment of embryonal RMS xenografts in zebrafish embryos at 3 hours postfertilization (hpf) under optimized temperature conditions.
• Drug screening using low numbers of viable tumor cells and water-soluble chemicals.
• Assessment of antitumor efficacy by measuring tumor cross-sectional area at 120 hpf.

Main Results:

• Successful establishment of RMS xenografts in zebrafish embryos.
• Proof-of-principle experiments demonstrated significant tumor reduction with clinically relevant drugs (vincristine, dactinomycin) and trametinib.
• The model showed sensitivity to chemotherapeutic agents with known anti-RMS activity.

Conclusions:

• Zebrafish embryo xenografts provide a rapid and cost-effective model system for RMS research.
• This model can serve as a valuable addition to existing cell culture and mammalian models for preclinical drug testing.
• The developed model holds potential for accelerating the discovery of new therapies for rhabdomyosarcomas.