Role of Urokinase-Type Plasminogen Activator Receptors as an Early Detector for Treatment Outcome in Adult Acute Myeloid Leukemia in Egyptian Patients

Background: The urokinase-type plasminogen activator system which consists of a proteinase (the urokinase-type plasminogen activator, uPA), a receptor (the urokinase-type plasminogen activator receptor uPAR or CD87) and inhibitors (PAI1) is enriched in several types of tumors and involved in proteolysis, cell migration and invasion. High expression of uPA and uPAR is associated with an increased relapse rate and shorter survival in breast cancer and colorectal carcinomas. Aims: This study shed light on the expression of uPAR in adult acute myeloid leukemia (AML) and its prognostic relevance. Methods: Peripheral blood and bone marrow samples are obtained from 54 newly diagnosed AML adult patients, 20 healthy controls stained with anti CD87 and estimated on flow cytometry. Results: CD87 expression was heterogeneous in different FAB subtypes of AML with high expression in monocytic leukemia (M4/M5) (P value 0.001). High expression of CD87 was associated with shorter survival and poor response to therapy (P = 0.028, 0.002 respectively). The most discriminating cut off value of CD87 expression was 20%, patients with less than 20% expression had 4.6 times better treatment outcome than those with more than or equal to 20%. On the multivariate analysis, CD87 was the most significant single variable that affect treatment outcome compared to total leucocytic count, hemoglobin level, platelets count, cytogenetic and FLT expression. Summary/Conclusion: High CD87 expression is an independent prognostic parameter associated with poor response and shorter overall survival in adult AML patients.