CXCR4 is a valuable poor prognostic marker for chronic lymphocytic leukemia: its higher level of expression is associated with inferior response to therapy and lower disease-free survival

Abstract

Background Chronic lymphocytic leukemia (CLL) is one of the common chronic lymphoproliferative disorders (lymphoid neoplasms). It is characterized by a progressive accumulation of functionally incompetent lymphocytes, which are usually monoclonal in origin. CLL is a heterogeneous disease; thus, in some cases, the disease progresses so slowly that treatment is not required, but in others, a more aggressive form of the disease develops. CXCR4 (CD184) is a chemokine and chemokine receptor pair playing critical roles in tumor genesis. It is overexpressed in many hematological malignancies including acute myeloid leukemia and non-Hodgkin’s lymphoma and generally correlates with a poor prognosis. Aim To evaluate the clinical utility of CXCR4 expression in patients with CLL as a possible predictor of disease outcome. Patients and methods This is a prospective study conducted on 33 adult patients with newly diagnosed CLL. Expression of CXCR4 was determined by flow cytometry on either peripheral blood or bone marrow samples. Correlation with the course of the disease and the known CLL prognostic parameters was done initially and after 6 months of follow-up. Results CXCR4 expression was positively correlated with absolute lymphocytic count, Rai score, β2 microglobulin, and lactate dehydrogenase levels. It was negatively correlated with hemoglobin and platelet counts, overall response rate, and 6-month disease-free survival. Conclusion We conclude that CXCR4 is a valuable poor prognostic marker for CLL. Its higher level of expression is associated with inferior response to therapy and lower disease-free survival.