FiGURE 1

Transplanted cancer cells survive in vivo in zebrafish embryos and their growth can be inhibited by small molecules. (A) Correlation of fluorescence to luminescence as measured in transplanted zebrafish embryos at 1 day post-injection (dpi). Every dot is a readout from a single embryo. On the left, the correlation of EGFP to NanoLuc in ZMEL1 is shown [slope is significantly non-zero, p = 0.0001, Goodness of fit (R) = 0.4916]. On the right, the correlation of mCherry to NanoLuc in K562 is shown [slope significantly non-zero, p = 0.0251, Goodness of fit (R) = 0.1563]. (B) Growth and drug inhibition of growth of ZMEL1 cells in zebrafish embryos, 1–6 dpi. ZMEL1 cells grew significantly in vivo from 1 to 6 dpi. The growth was significantly inhibited by a BRAF inhibitor, dabrafenib. Below, there is a representative image of a 1 dpi casper, prkdc^−/− zebrafish embryo transplanted with green ZMEL1-EGFP-NLuc cells, imaged in the green GFP channel. (C) Growth and drug inhibition of growth of K562 cells in zebrafish embryos, 1–6 dpi. K562 cells grew significantly in vivo from 1 to 6 dpi. The growth was significantly inhibited by imatinib. Below, there is a representative image of a 1 dpi casper, prkdc^−/− zebrafish embryo transplanted with red K562-mCherry-NLuc cells, imaged in the red mCherry channel. (B,C) Statistical significance was determined by unpaired two-tailed t-test. *p < 0.05 ***p < 0.001. Luminescence measured in vivo in single embryos is represented by a single dot in dot plots. Fluorescence images were acquired on Zeiss AxioZoom.V16 with Axiocam-506 mono camera and the ZEN Blue software.