Dipeptidyl peptidase-4 (CD26): a prognostic marker in patients with B-cell chronic lymphocytic leukemia

Abstract

Introduction B-cell chronic lymphocytic leukemia (B-CLL) is an incurable disease; nevertheless, its prognosis varies widely among patients. CD26 is considered a cell adhesion molecule. It is suggested that CD26 expression is involved in tumor growth, invasion, and metastasis. Aim The aim of this study was to assess the prognostic value of dipeptidyl peptidase-4 (CD26) in patients with B-CLL and its relation to the clinical and laboratory parameters. Patients and methods This case–control study was carried out from April 2013 to April 2016, and it was performed on 75 newly diagnosed B-CLL patients admitted at Hematology and Oncology Unit, Department of Internal Medicine, Tanta University Hospital, Egypt; 30 apparently healthy individuals were involved in the study as the control group. Dipeptidyl peptidase-4 (CD26) expression was evaluated by flow cytometry. Results The main finding in this study was that CD26 expression was increased in B-CLL patients in comparison with normal subjects. There was also a positive correlation between white blood cell count, absolute lymphocytosis, clinical staging of B-CLL patients, and CD26 expression. Overall survival (OS) and disease-free survival (DFS) were shorter in B-CLL patients with positive CD26 expression compared with patients with negative CD26 expression. Patients with positive CD26 expression had significantly shorter OS (16 vs. 20 months) and significantly lower DFS (6 vs. 16.5 months) at 24 months compared with those with negative CD26 expression. Conclusion CD26 expression was significantly higher in B-CLL patients compared with healthy subjects, and its expression among B-CLL patients correlated with poor laboratory data, clinical staging, OS, and DFS, and thus it may play a role in prognosis of B-CLL. CD26 could be used as a prognostic marker either alone or in combination with other markers in assessment of B-CLL patients.