ISPO

Published in Cancer Detection and Prevention 2004; 28(6):433.

2-Chlorodeoxyadenosine alone and in combination with cyclophosphamide and mitoxantrone induce apoptosis in B chronic lymphocytic leukemia cells in vivo

Malgorzata Rogalinska PhDa; Jerzy Z. Blonski MD, PhDb; Margaret Hanausek PhDc; Zbigniew Walaszekc PhDc; Tadeusz Robak MD, PhDb; Zofia M. Kilianska PhDa

aDepartment of Cytobiochemistry, University of Lódz, S. Banacha 12/16, 90-237 Lódz, Poland; bDepartment of Hematology, Medical University of Lódz, Pabianicka 62, 93-513 Lódz, Poland; cAMC Cancer Research Center, 1600 Pierce Street, Denver CO 80214, USA

The purpose of the study was to determine some apoptotic events in mononu-clear cells obtained from peripheral blood of patients with Bcell chronic lymphocytic leukemia (B-CLL) during and after therapy with 2-chlorodeoxyadenosine (2-CdA; C), and the combination of 2- CdA with cyclophosphamide (CC), or 2-CdA with mitoxantrone and cyclophosphamide (CMC). Western blot technique was performed to estimate expression/proteolytic degradation of generally accepted apoptotic markers, i.e., Bcl-2 protein, lamin B, PARP-1, and caspase-3 in leukemic cells isolated from blood samples of patients before treatment and subjected to drug(s) administration. The decrease of antiapoptotic protein Bcl-2 expression and proteolytic cleavage of nuclear proteins—amin B and PARP-1 were observed in leukemic cells of patients treated according to the above therapy protocols, however, each to a different level among the studied groups. The obtained results indicated also that procaspase-3 was cleaved and activated in leukemic cells of three drug(s) treated groups. However, the cleavage of procaspase-3 and the generation of fragments with mol. mass of 17/20 kDa occurred especially effectively among patients treated according to CMC regimen. The changes in expression/proteolytic degradation of the above selected apoptotic markers, are accompanied by the appearance of apoptotic morphology in leukemic cells originated from blood of patients treated with the above drug(s) in comparison to untreated ones.

KEY WORDS: Drug-induced apoptosis, Bcl-2, Lamin B, Caspase-3, Western blot, Apoptotic morphology.

http://www.cancerprev.org/Journal/Issues/28/6/4910