Fig. 3: Metastatic mammary cancer cells remodel the bone marrow vasculature upon expansion.

a Tile scan (top) and enlarged (bottom) 3D images of femoral BM stained for DAPI (grey), 4T1.2 cells (magenta), EMCN (yellow) and CD31 (cyan) reveal vessel remodelling in tumour-infiltrated area (met) but not in the adjacent tumour-free area (non-met) (n = 5 mice). Scale bars, 1 mm (top), 100 µm (bottom). b Box and whisker plots of mean vascular CD31 and EMCN voxel intensity of individual vessels in non-met and met areas from n = 5 mice. Centre line; median; box limits, from the 25th to 75th percentiles; whiskers, from the 5th to 95th percentiles. ***P < 0.0001 by two-tailed unpaired t test. c Left: 3D image of femoral BM stained for DAPI (grey), 4T1.2 cells (magenta), EMCN (yellow) and CD31 (cyan). Right: zoomed-in images of met and non-met area (corresponding to (i) and (ii) from the left panel, respectively) (n = 7 mice). Arrowheads indicate EMCN⁺CD31⁺ vascular sprouts. Scale bars: 500 µm (overview), 50 µm (enlargement). d Digital reconstructions of CD31-positive blood vessels in non-met and met areas. Scale bar, 50 µm. e Measurements of endothelial surface area over vessel length from (d). n = 7 (non-met) and 9 mice (met). P value, two-tailed unpaired t tests. f 3D images of CD31-positive blood vessels (cyan) in non-met and met area. Right panel shows optical section from the selected area in left panel. Yellow lines demarcate vessel lumen. Scale bars: 20 µm. g Lumen area from (f). Individual dots are from one vessel. n = 5 (non-met) and 10 mice (met). P value, two-tailed unpaired t tests. All data reflect mean ± s.e.m. Source data are provided as a Source Data file.