Altogether, our results showing increased plasma concentrations of SDC-1, ESM-1, sVCAM-1 and Angpt-2 seem to reflect a local pulmonary endothelial response to murine metastatic breast cancer development involving glycocalyx disruption, endothelial inflammation and increased endothelial permeability that, together with a low-NO pulmonary microenvironment – reported previously in this model (Smeda et al., 2018; Buczek et al., 2018) – might all promote metastases development. This evidence concerns the gene ESM1 and breast cancer.