Whole Body Melanoma Transcriptome Response in Medaka

Area of Science:

• Comparative oncology
• Genomics
• Immunology

Background:

• Malignant melanoma incidence and relapse rates are rising, necessitating novel therapeutic strategies.
• Fish melanoma models offer conserved gene expression signatures with human melanocytes, making them valuable for research.

Purpose of the Study:

• To investigate the whole-body transcriptome response to invasive melanoma in a medaka fish model.
• To establish a foundation for using transcriptome profiling to screen for anti-melanoma drugs.

Main Methods:

• RNA sequencing (RNA-seq) was performed on whole-body RNA isolates from control and melanoma-bearing medaka fish.
• Differential gene expression analysis identified significant transcriptomic changes between melanoma and control groups.
• Ortholog mapping was used to compare fish gene expression changes with human melanoma data.

Main Results:

• 396 genes showed significantly different expression in medaka melanoma, with 379 having human orthologs.
• Canonical pathway analysis highlighted antigen presentation and melanocyte development pathways.
• A significant down-regulation of immune response genes, particularly the innate immune system, was observed.

Conclusions:

• The study suggests that developing melanoma actively suppresses the host immune response, contributing to disease progression.
• The whole-body transcriptomic approach in medaka is a viable method for melanoma research and drug screening.
• Novel genes and potential drug targets for human melanoma were identified.