Levels of circulating endothelial adhesion molecules (sE-selectin and sVCAM-1) in adult patients with acute leukemia.

The spread of leukemia extends from mobilization of leukemic blast cells from the bone marrow to extramedullary tissue infiltration. Migration of leukemic blasts resembles that of neutrophils and may be regulated by activated endothelial cells via endothelial adhesion molecules such as E-selectin, VCAM-1 and ICAM-1. Plasma levels of soluble adhesion molecules may therefore indicate interaction between leukemic blasts and endothelium, and may be related to leukemic cell mass or subtype of leukemia. In this study, plasma levels of soluble E-selectin, VCAM-1 and ICAM-1 were analyzed in 40 untreated patients with acute leukemia (35 ANLL, five ALL). Plasma concentrations of all three receptors were significantly elevated when compared to healthy controls (P = 0.006, P = 0.0001, and P = 0.0001, respectively) but demonstrated high interindividual variations among leukemic patients. sE-selectin but not sVCAM-1 and sICAM-1 levels correlated with peripheral leukocyte and blast cell counts. Increased levels of either sE-selctin or sVCAM-1 were present in 32 out 40 leukemic patients (80%). FAB subgroups differed in levels of sVCAM-1. The highest levels were measured in acute myelomonocytic and lymphoblastic leukemia, ie in leukemia subtypes with a high incidence of extramedullary blast cell infiltration.