In order to investigate the role of tryptase in angiogenesis of acute leukemia (AL), the expressions of tryptase and vascular endothelial growth factor (VEGF) in leukemic cells from 61 patients with AL were examined by using immunocytochemical method, and the correlation between tryptase and VEGF was analyzed. The results showed that tryptase positive expression was found in 15 out of 51 patients with acute myeloid leukemia (AML) (M(1) 1/3, M(2) 7/15, M(3) 5/20, M(5) 2/8). Tryptase positive expression was 29.4% in AML. However, none of 10 patients with acute lymphocytic leukemia (ALL) showed tryptase expression. There were no correlations between the amounts of cells with tryptase expression and patient age, WBC count, numbers of blood or marrow myeloblasts and neutrophil POX. VEGF expression was revealed in 41 patients with AML (80.4%) and only 3 with ALL (30%). Significant correlation has been found between the expression of tryptase and that of VEGF in AML-M(2) (r = 0.65, P < 0.05). It is concluded that tryptase appears to be a myeloid-specific marker in AML and may be involved in the angiogenesis of AML-M(2).
Biomarkers, Tumor ; biosynthesis ; Humans ; Immunohistochemistry ; Leukemia, Monocytic, Acute ; metabolism ; pathology ; Leukemia, Myeloid, Acute ; metabolism ; pathology ; Leukemia, Promyelocytic, Acute ; metabolism ; pathology ; Neovascularization, Pathologic ; Tryptases ; biosynthesis ; Vascular Endothelial Growth Factor A ; biosynthesis