[Cell adhesion molecules: expression and function in acute myeloid leukemia]

Adhesion molecules play a major role in the regulation of normal hematopoiesis. Precursor/cell matrix/endothelial interactions determine retainment or release of hematopoietic cells from the bone marrow microenvironment. Consequently, changes in the affinity or quantitative expression of adhesion molecules on either the bone marrow stroma or the cell precursor component during a malignant process will affect cell attachment. Adhesion molecules, therefore, are modulator molecules which alter the biological behavior of leukemic cells in terms of migration and localization properties. Several membrane-bound adhesion molecules and, in some instances, their soluble counterparts which may be biologically active, have been described in acute myeloid leukemia. The panel of receptors expressed demonstrates heterogeneity between various cases of acute myeloid leukemia. There is generally no correlation between the adhesion receptor phenotype and the morphologic or clinical features of acute leukemia. These receptors function in interactions of leukemic blasts with the cellular and matrix components of the marrow microenvironment. Adhesive interactions may influence the proliferation and survival of leukemic cells. However, the precise role that these molecules play in the generation and sustenance of the leukemic state remains undetermined.