Fig. 7. CX-4945 and FTY720 combination therapy induces AML cell death in zebrafish xenograft models.

In vivo proliferation and invasive potential of HL60 and MOLM-13 cells upon treatment with FTY720, CX-4945 or the combination of both compounds were analyzed in a xenograft zebrafish model. a Timing scheme for the xenografts of zebrafish embryos. b Measurement of proliferation index performed as fluorescence intensity medium value* RF pixel, demonstrating cell proliferation of treated cells in the xenograft model. c Representative pictures of Tumor growth of HL60 treated cells in zebrafish embryos 2 hpx (reference fluorescence) and 72hpx. Scale bars represent 0.1 mm. d Representative pictures of zebrafish embryos injected with MOLM-13 cells and treated with DMSO or combination of CX-4945 (1 µM) and FTY720 (1 µM), which show the cells that migrated to the tail after the treatment mentioned. Magnified pictures on the bottom show the invasion of cells in the tail. Scale bars from whole zebrafish picture represent 0.5 mm and from zoom 0.1 mm. e Quantification of the invasive potential of the injected cells upon drug treatment. Quantification performed as colonization index: count of zebrafish embryos with invasion of cells migrating outside the yolk sac referred to the control embryos (injection of DMSO treated cells). Hpx: hours post-xenograft. **p < 0.01, ***p < 0.001 vs. DMSO treated cells. f In vivo proliferation and invasive potential of HL60 and MOLM-13 cells upon infection with shp38β pINDUCER11 treated with and without doxycycline in a xenograft zebrafish model measured at 72hpx. **p < 0.01, ***p < 0.001 vs. control cells.