VASH1 and cancer: Contrary to expectations, most studies have shown that an increased intensity of VASH1 immunostaining in tumor vessels was associated with poor clinical outcomes.13, 14, 15, 16, 17, 18, 19, 20 Immunohistochemical analysis has shown the VASH1 protein in the cytoplasm of ECs, and the intensity of VASH1 immunostaining is positively correlated with that of VEGF in cancer cells.10, 13 As the degradation and inactivation of VASH1 after secretion are enhanced in the tumor microenvironment,24 immunohistochemical staining of VASH1 in ECs may not correlate with its antiangiogenic activity.