Expression and function of adhesion receptors in acute myelogenous leukemia: parallels with normal erythroid and myeloid progenitors.

A variety of adhesion receptors are expressed on the blast cells in patients with acute myelogenous leukemia. The panel of receptors expressed demonstrates heterogeneity just as there is morphologic, histochemical, cytogenetic, and molecular genetic variation between various cases of acute myelogenous leukemia. The adhesion receptors expressed contain representatives of all the main classes of adhesion receptors, but often there is no correlation of the adhesion receptor phenotype with the morphologic or clinical features of acute myelogenous leukemia. These receptors function in interactions of myelogenous leukemia blasts with the cellular and matrix components of the marrow microenvironment, and there is evidence that they are involved in blast release from marrow and in homing of blasts to extramedullary sites. Evidence is starting to accumulate suggesting that adhesive interactions may influence the proliferation and survival of leukemic cells, but the precise role that these molecules play in the generation and sustenance of the leukemic state remains undetermined.