ZAP70 Expression Within del6q21, del11q13 and del17p13 Cytogenetic Subgroups of Iranian Patients with Chronic Lymphocytic Leukemia

BACKGROUND B-cell chronic lymphocytic leukemia (B-CLL) is the most common form of leukemia in adults. Some reports showed that expression of ZAP70 gene and chromosomal abnormality are two prognostic factors in management of B-CLL. OBJECTIVES In this study, we determined ZAP70 mRNA expression level in the del17p13, del6q21 and del11q13 subgroups of Iranian B-CLL patients to investigate prognostic value of ZAP70 expression. PATIENTS AND METHODS In this cross-sectional study, fluorescence in situ hybridization analysis was carried out on 66 Iranian B-CLL patients. Zap70 mRNA expression was evaluated by using Real Time RT-PCR. RESULTS Molecular analysis showed that ZAP70 expression increased 2.46 fold in the del11q13 subgroup, 2.87 fold in the del17p13 and 1.87 fold in the del6q21, compared to the 15 patients in the control group. Comparison of standard deviation and mean of the ZAP70 expression profile within the subgroups showed more variability among the cases of the del11q13 and del17p13 versus tight clustering for the del6q21. Therefore, there is a relation between del6q21 aberrations; which has good prognosis with normal levels of ZAP70 expression. CONCLUSIONS The results of ANOVA test showed that ZAP70 expression gene was significantly increased in del17p13 and del11q13 subgroups compared to control group. Thus, ZAP70 may play an important role in the prognosis of B-CLL patients.