Fig. 1

Establishment of zebrafish NSCLC BM xenograft models. (A) Schematic diagram of imaging and collecting zebrafish brain. The zebrafish brain was imaged from vertical view (blue arrow) and excised (red dotted box) to extract RNA. (B) The schematic diagram showed zebrafish embryos at 2 dpf. The red dots indicated cancer cells injected into the perivitelline space (PVs). (C) Images of brain at different developmental stages of Tg (fli-1: EGFP) zebrafish (2-6 dpf). The white short dashed line indicated the midbrain of the zebrafish, and the white long dashed line indicated the zebrafish’s eyes and hindbrain. (D) The expression of claudin-5 in the zebrafish brain at different developmental stages (2-7 dpf). (E) The expression of mfsd2aa and mfsd2ab in the zebrafish brain at different developmental stages (2-6 dpf). (F) Survival curves of 2 dpf zebrafish with different tumor-bearing amount in PVs. About 50-400 H1975 cells (red fluorescence) were injected into the PVs of 2 dpf zebrafish, and the number of deaths was counted till 8 dpi. (G-I) Three human NSCLC cell lines were involved: H1975, A549 and H1299. About 100 cells were injected into the PVs of zebrafish at different developmental stages, and the brain of zebrafish was imaged at 1 dpi. The white arrows indicated cancer cells in blood vessels of zebrafish brain. (J-K) Quantification of the BM cells number in zebrafish at 1 dpi. Significance was considered when P values were lower than 0.05. (ns) indicated statistical insignificance, (*) indicated statistical significance P < 0.05, (**) P < 0.01 and (***) P < 0.001. dpf: days post fertilization, dpi: days post injection