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Background Lenalidomide improves erythropoiesis in patients with low/intermediate-1 risk myelodysplastic syndrome and interstitial deletion of the long arm of chromosome 5 [del(5q)]. The aim of this study was to explore the effect of lenalidomide treatment on the reserves and functional characteristics of bone marrow hematopoietic progenitor/precursor cells, bone marrow stromal cells and peripheral blood lymphocytes in patients with low/intermediate-1 risk myelodysplastic syndrome with del(5q). Design and Methods We evaluated the number and clonogenic potential of bone marrow erythroid/myeloid/megakaryocytic progenitor cells using clonogenic assays, the apoptotic characteristics and adhesion molecule expression of CD34+ cells by flow cytometry, the hematopoiesis-supporting capacity of bone marrow stromal cells using long-term bone marrow cultures and the number and activation status of peripheral blood lymphocytes in ten patients with low/intermediate-1 risk myelodysplastic syndrome with del(5q) receiving lenalidomide. Results Compared to baseline, lenalidomide treatment significantly decreased the proportion of bone marrow CD34+ cells, increased the proportion of CD36+/GlycoA+ and CD36−/GlycoA+ erythroid cells and the percentage of apoptotic cells within these cell compartments. Treatment significantly improved the clonogenic potential of bone marrow erythroid, myeloid, megakaryocytic colony-forming cells and increased the proportion of CD34+ cells expressing the adhesion molecules CD11a, CD49d, CD54, CXCR4 and the SLAM antigen CD48. The hematopoiesis-supporting capacity of bone marrow stroma improved significantly following treatment, as demonstrated by the number of colony-forming cells and the level of stromal-derived factor-1α and intercellular adhesion molecule-1 in long-term bone marrow culture supernatants. Lenalidomide treatment also increased the proportion of activated peripheral blood T lymphocytes. Conclusions The beneficial effect of lenalidomide in patients with lower risk myelodysplastic syndrome with del(5q) is associated with significant increases in the proportion of bone marrow erythroid precursor cells and in the frequency of clonogenic progenitor cells, a substantial improvement in the hematopoiesis-supporting potential of bone marrow stroma and significant alterations in the adhesion profile of bone marrow CD34+ cells.

Cell cycle control is a crucial event in normal hematopoiesis, and abnormalities of regulatory cell cycle genes have been found to contribute to the development of many hematologic malignancies. The present study investigates the immunohistochemical expression of seven essential cell cycle proteins (p21, p27, p14, p16, p53, mdm2, and cyclin E) in paraffin-embedded sections from 42 bone marrow biopsies obtained from an equal number of patients with newly diagnosed acute myeloid leukemia (AML). This study revealed (i) a high frequency of p53+/mdm2-/p21-phenotype, which is probably a result of p53 gene mutation and/or inhibition of mdm2 action by p14(ARF); (ii) expression of p27+/cyclinE-phenotype in most cases, suggesting that p27 may act as a potent cyclin-dependent kinase inhibitor; (iii) expression of p16 only in very few cases; and (iv) no relationship between the expression of any of the above proteins and survival as well as histologic subtype.

The standard CHOP regimen may cure 30-40% of patients with advanced aggressive non-Hodgkin's lymphoma (ANHL). Mitoxantrone is an anthracenedione, which is active in NHL and its toxicity profile may be more favorable than doxorubicin with respect to alopecia, mucositis and cardiotoxicity. This study was designed to compare the effectiveness of an escalated dose of mitoxantrone with that of standard doxorubicin, used in the CHOP regimen in patients with ANHL. One hundred and forty three eligible patients with ANHL were randomized to receive 6 cycles of either CHOP (n = 71) or intensified CNOP (iCNOP) (n = 72), with mitoxantrone 20 mg/m2, i.v., d.1 instead of doxorubicin. Complete responders (CR) were again randomized either to receive interferon-alpha (IFN-alpha) maintenance (3 MU t.i.w., s.c.) or not. The CR rate was 70 vs. 76% for iCNOP and CHOP (p = 0.45), and the overall response rate was 81 vs. 83%, respectively (p = 0.71). The 5-year failure free survival (FFS) was 48 and 50% in the iCNOP and CHOP arm, respectively (p = 0.45), and the 5-year overall survival (OS) was 61 vs. 64% (p = 0.56). IFN-alpha did not prolong relapse free survival (p = 0.91). iCNOP produced less alopecia (p = 0.001) but more febrile episodes (p = 0.04) than CHOP, while requiring more frequent G-CSF support (p = 0.01). Two cases of acute myelogenous leukemia (AML) were recorded, both in the iCNOP arm (p = 0.14). In conclusion, iCNOP was equally effective to CHOP in patients with ANHL, producing more leukopenia and febrile episodes, but less alopecia. The development of two cases of secondary AML in th e iCNOP arm is of concern. Leuk Lymphoma

The multidrug resistance (MDR) transporter-proteins P-glycoprotein (Pgp), multidrug resistance protein (MRP) and lung resistance protein (LRP) have been associated with treatment failure. The aim of this study was to investigate prospectively the clinical significance of expression and function of the MDR proteins, considering other prognostic factors, such as age, immunophenotype, and cytogenetics. Mononuclear cells of peripheral blood or bone marrow from 61 patients with de novo acute myelogenous leukemia (AML) were analyzed. The monoclonal antibodies JSB1, MRPm6 and LRP56 were used for expression studies. Accumulation and retention studies were performed using the substrates Daunorubicin, Calcein-AM, Rhodamine-123 and DiOC2 in the presence or absence of the modifiers Verapamil, Genistein, Probenecid, BIBW22S and PSC833. Induction treatment consisted of a 3 +7 combination of Ida/Ara-C for patients 60 years of age and a 3 + 5 Ida/VP-16 combination per OS for patients 60. MDR function was expressed as the ratio of mean fluorescence intensity substrate in the presence of modifier over the substrate alone (resistance index, RI). Patients with advanced age, low CD15 expression and high RI for accumulation of DiOC2 in the presence of BIBW22S had significantly lower complete remission (CR) rates. No factor was prognostic for event-free survival analysis, which was limited to remitters only. Overall survival was shorter in patients with advanced age, poor prognosis cytogenetics, high CD7 expression, and high RI for Daunorubicin efflux modulated by Verapamil. These results suggest that MDR transporter-proteins have a limited role in the treatment failure of patients treated with Idarubicin-based regimens. © 2002 Elsevier Science Ltd. All rights reserved.