clinical utility of LPL and ZAP-70 expression in assessment of prognosis in patients with B-cell chronic lymphocytic leukemia

ABSTRACT

It was found that B-CLL patients with unmutated immunoglobulin heavy chain variable region [IgVH] have poor prognosis and clinical outcome. The difficulty of performing the mutation status of IgHV in the routine diagnostic workup of B-CLL patients, prompts the search for surrogate markers particularly gene expression profile in B-CLL cells. To investigate the role of LPL and ZAP-70 expression in assessment of prognosis and survival in a group of B-CLL patients and correlate the results with other prognostic variables. The study included 47 B-CLL patients who were subjected to clinical staging which was done by Binet and Rai scoring systems. The expression of LPL and ZAP-70 was measured by real-time quantitative PCR [RQ-PCR] and flow-cytometric analysis respectively. The patients were followed over 24 months for proper estimation of treatment free survival [TFS] and disease free survival [DPS]. The results of our study showed positive LPL and ZAP-70 expression in 46.8% and 48.9% of B-CLL patients respectively. There was significant correlation between LPL and ZAP-70 positive expression in our patients [p<0.0001]. The positive expression of both genes is associated with advance in clinical staging with significant correlation between LPL and ZAP-70 positive expression and shortening of the TFS and DPS and subsequent classification of most of the LPL+ and ZAP-70+ cases as patients with poor prognosis. Our study showed that expression of LPL and ZAP-70 has a significant role in determining the prognosis in B-CLL patients, being positive expression of LPL and ZAP-70 is associated with poor prognosis with shortening of TFS and DPS. Also, both genes expression is of great value in selection of B-CLL patients in early clinical stages that are in need to start chemotherapy to avoid progression to aggressive forms of the disease