Vascular function is tightly regulated by structural and architectural cues. Several functional abnormalities in the bone marrow (BM) vasculature have been reported (e.g. increased permeability, altered perfusion and loss of healthy hematopoietic stem cells) (Passaro et al., Cancer Cell 2017; Gomes et al., Haematologica 2021). High throughput RNA-sequencing analysis of BM-derived endothelial cells (ECs) have shown multiple molecular alterations (Passaro et al., Cell Reports 2021).  By using intravital 2P imaging and transgenic mouse models, we investigate how the pathologic remodeling of adhesion molecules in the endothelium mediates the leukemia interaction with the niche and supports leukemia growth.