Some cells of aggressive melanomas also express characteristic genes of other types of cells including endothelial, nerve and stem and prove then differentiated. A research was set up to see if the zebrafish model was functional for the study of such tumors as well as their interactions with the embryonic microenvironment.
Cells of malignant melanoma have been transplanted in zebrafish embryos. The cells survive, they have motility and they divide. They don’t integrate with the tissues of the host but spread in the interstitial spaces of the embryo following their metastatic characteristic and reflecting the behavior of undifferentiated cells of the tumor. However they do not produce the tumor.
The human melanocytes transplanted in the zebrafish embryo are distributed on the skin revealing that the zebrafish has receptors that can be recognized by human cells.
It has also been shown that in the embryo of zebrafish metastatic cells of melanoma maintain their phenotype undifferentiated but they do not progress towards tumor formation. These results demonstrate the usefulness of the model of the embryonic zebrafish for studies about the adaptability of the tumor cells and suggest that this experimental paradigm permits us to study the interaction of the embryo’s microenvironment with the tumor cells.