To investigate the tumour burden kinetics in the presence of the nanoparticles in comparison to the vehicle control, 2dpf zebrafish embryos were injected with the co-suspension of CD44 + and CD44- U-251 MG cells labeled with different fluorescent cell trackers in the presence of HA-CPNs or their absence (vehicle control) (Fig. S6C, left). This evidence concerns the gene CD44 and neoplasm.