Examples of Tumors in Flies and Fish

(A) RAS^G12V; PTEN^−/− double mutant clones formed large glial-derived tumors in the fly brain. Red, repo (all glia); green, GFP (transformed glia). Insert shows the abnormally high density of glial-cell nuclei. From Read et al., 2009.

(B) High magnification view of a multi-target (involving four mutations) cancer model achieved by overexpressing RAS^G12V and using RNAi-mediated knockdown of PTEN, APC, and P53. Green, transformed hindgut cells; red, muscle cells; and blue, trachea. See Bangi et al., 2016.

(C) A transgenic zebrafish melanoma model. Expression of BRAF^V600E under the melanocyte-specific mitfa promoter resulted in stripe disruption and nevi. When crossed with p53-mutant fish, the resultant mitfa-BRAF^V600E;p53^−/− fish developed melanomas with 100% penetrance.

The ZMEL/Casper Transplant Assay Allows for Single-Cell Resolution of the Entire Metastatic Cascade

(A) The ZMEL1 line is derived from a transgenic zebrafish melanoma. It is then transplanted into the skin of the transparent casper recipient.

(B) Tumors initiate at a defined spot where cells are injected (blue arrow) and metastases (red arrows) can then be followed over time.

(C) An example of a single extravasating ZMEL1-GFP cell at a distant site show its appearance while still in the blood vessel (marked by an flk-RFP transgene) and immediately after extravasation out of the blood vessel.