ABSTRACT
A total of 50 patients with chronic lymphocytic leukaemia (CLL), as well as the B-cell leukaemia cell lines MEC-1, JVM-3, and BV-173 were studied in order to assess the incidence of CD13/aminopeptidase N (APN) immunolabelling with a monoclonal antibody 7H5 compared to LeuM7 and to CD13 mRNA levels, and to correlate these data with the cytotoxic and apoptosis-induction activity of the natural phenolic APN inhibitor curcumin. CD13/APN was detected in a significant proportion of B-CLL patients (42/50, 84%), immunolabelled by 7H5 (42/50) ± LeuM7 (10/50). Molecular analysis for CD13 transcripts confirmed these data, resulting in a specific RT-PCR product in CD13 positive cases. Curcumin showed concentration-dependent cytoreductive efficacy and apoptosis-induction activity in all tested cell lines and primary cultures from CLL mononuclear cells. There was a clear tendency for a better response in CD13 positive cases. The incidence of CD13/APN in CLL suggests that the inhibition of APN/CD13 by curcumin may be an effective new molecular target for a more efficient therapy for these patients and warrants further investigations.
Subject(s)
Antineoplastic Agents/pharmacology , CD13 Antigens/genetics , Curcumin/pharmacology , Gene Expression , Leukemia, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Apoptosis/drug effects , CD13 Antigens/antagonists & inhibitors , Cell Line, Tumor , Dose-Response Relationship, Drug , Gene Expression/drug effects , Humans , Leukemia, B-Cell/drug therapy , Leukemia, B-Cell/pathology , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Middle Aged , Primary Cell Culture , RNA, Messenger/biosynthesisABSTRACT
Bone marrow samples of 17 acute myeloid leukemia (AML) patients were analyzed for apoptosis-related markers. The levels of active caspase-3 (aC-3), Bcl-2 and cleaved poly(ADP-ribose) polymerase (cPARP) were measured by flow cytometry and compared with survivin and MDR1 gene expression as defined by reverse transcriptase polymerase chain reaction (RT-PCR). The results showed heterogeneous patterns of intracellular levels of the studied proteins in AML patients: aC-3 (mean 34.6+/-52.5 U/ml), Bcl-2 (mean 3268.4+/-2055.2 U/ml), and cPARPs (mean 24.59+/-29.97 U/ml). Survivin and MDR1 genes were overexpressed in 9 and 10 patients, respectively. Patients with high levels of survivin mRNA showed significantly lower cPARPs (11.8+/-14.3 versus 53.9+/-31.9 U/ml P=0.005) and a tendency towards higher aC-3 (49.3+/-70.0 versus 18.1+/-9.9 U/ml), and MDR1 overexpression (7/9 patients versus 3/8 patients), as well as poorer therapeutic response and survival. Our data support the potential relevance of apoptosis-related markers in AML for further understanding the disease; however, the heterogeneity and complexity of molecular interactions warrants further prospective studies.
