ZAP-70 Expression and its Prognostic Significance in Childhood B-lineage Acute Lymphoblastic Leukemia

Abstract

Background: ZAP-70 expression was found in normal human B cell precursors and B lymphoproliferative disorders. Since the level of ZAP-70 expression is prognositic in chronic lymphocytic leukemia, a similar role may be demonstrable in other B-lineage malignancies. The present study investigates the expression of ZAP-70 in B-lineage acute lymphoblastic leukemia and its prognostic significance. Methods: Thirty-three bone marrow and blood samples were obtained from children newly diagnosed with B-lineage ALL. ZAP-70 was determined using flow cytometry. Correlation between expression of ZAP-70 and clinicobiological presenting features (age, sex, white blood cells) and cytogenetics was performed. Results: ZAP-70 was expressed in all cases with a wide variation (0.11 - 87.68%). There is no correlation between ZAP-70 expression level and clinicobiological presenting features also the cytogenetics abnormalities was found. Aberrantly high expression of ZAP-70 was found in three cases, two of which had aberrant CD13 and CD33 co-expression. Conclusions: Aberrantly high expression of ZAP-70 might be associated with certain subgroup (CD13 and CD33 coexpression) of B-lineage ALL.