Evidence for a macromolecular complex in poor prognosis CLL that contains CD38, CD49d, CD44 and MMP-9

Progressive chronic lymphocytic leukaemia is characterized by the accumulation of neoplastic B-cells in the tissues and correlates with the expression of prognostic biomarkers, such as CD38, CD49d and matrix metalloproteinase-9 (MMP9), which are involved in migration and tissue invasion. In this study we investigated the physical relationship between these molecules and demonstrated that CD38, CD49d, MMP9 and CD44 were physically associated in a supramolecular cell surface complex. Our findings provide a molecular basis for the correlation between expression of these proteins and prognosis and, as the complex is not present in normal B-cells, suggest a novel leukaemia-specific therapeutic target.