Expression of Surface-associated 82 kDa proMMP-9 in Lymphatic Leukemia Blast Cells Differentially Correlates With Prognosis

Background/Aim: Matrix metalloproteinases (MMPs) degrade extracellular matrix and process regulatory proteins. Recently, a membrane-bound 82kDa variant of proMMP-9 identified on myeloid blasts was shown to be associated with prognosis. Patients and Methods: To investigate the role of 82kDa proMMP-9 with acute lymphoblastic leukemia (ALL) and chronic lymphoid leukemia (CLL), we performed flow-cytometry analysis of expression on ALL blasts (n=18) and CLL lymphocytes (n=21) from blood and correlated data with clinical parameters. Results: In ALL, mature B-linear blasts expressed higher levels of 82kDa proMMP-9 compared to T-linear blasts. Elevated levels of 82kDa proMMP-9 were found in elderly patients and at patients with relapse. No correlation was observed on blood cells and extramedullary disease. In CLL, the 82kDa proMMP-9 expression did not correlate with any of the clinical parameters. Conclusion: Our findings suggest that higher levels of 82kDa proMMP-9 expression on blast cells may correlate with a more unfavorable ALL-subtype. Further studies are required to clarify the prognostic role of the 82kDa pro-MMP-9 expression.