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Background and Objectives: In chronic lymphocytic leukemia (CLL) B-cells are refractory to activation signals and to apoptosis. CD40 triggering, however, rescues CLL B-cells from their anergic state and upregulates the FAS receptor. We therefore studied whether CD40 triggering enhances CLL B-cell sensitivity to fludarabine, and receptors or cytokines potentially involved in apoptosis., Design and Methods: CD40-activation of CLL B-cells was carried out by co-culture with CD40L-transfected cells. After fludarabine treatment, apoptosis was evaluated by propidium iodide (PI), annexin-V/PI or DiOC6 staining and flow cytometry analysis. Modulation of Bcl-2, of tumor necrosis factor receptor (TNFRI/II) and release of tumor necrosis factor (TNF)alpha/interferon (IFN)gamma was also analyzed. Furthermore, addition of caspase-inhibitors or anti-TNFalpha/-IFNgamma monoclonal antibodies to fludarabine-treated cells allowed us to determine the mediators of apoptosis. Student's t tests or ANOVA variance statistical analysis were performed to evaluate whether any differences observed might be considered significant., Results: CD40 triggering enhanced fludarabine sensitivity of CLL B-cells, downmodulated Bcl-2 and upregulated TNFRI/II. Caspases 1 and 6 were the major caspases involved in fludarabine apoptosis induction in resting B cells, while only anti-TNFalpha/-IFNgamma monoclonal antibodies reduced apoptosis in activated cells. In agreement with this observation, autocrine production of TNFalpha and IFNgamma by CD40-activated CLL B cells was found., Interpretation and Conclusions: B-cells from a considerable proportion of CLL cases studied (11/20) are more prone to fludarabine-induced apoptosis after CD40 triggering; accordingly Bcl-2 expression was lower in activated cells. Moreover, upregulation of TNFRI/II, release of TNFalpha and IFNgamma, and inhibition of apoptosis by anti-TNFalpha/-IFNgamma monoclonal antibodies in CD40-activated cells strongly suggest that these cytokines may play a role in sensitizing B-cells to fludarabine treatment.

Background and Objectives: Technetium-99m 2-methoxy-isobutyl-isonitrile ((99m)Tc-sestamibi) has recently been proposed as a potential tracer in patients with multiple myeloma (MM), as its increased uptake in the bone marrow has been reported as indicator of myeloma activity. We evaluated the role of (99m)Tc-sestamibi scintigraphy in the detection of myeloma bone disease in MM and related gammopathies, and also assessed its relationship with clinical status and stage of the disease, focusing in particular on the early follow-up of a small series of MM patients treated with high-dose therapy., Design and Methods: Forty-six consecutive patients affected by MM or monoclonal gammopathy of undefined significance (MGUS) were studied by whole body scans obtained 20 minutes after administration of 740 MBq of (99m)Tc-sestamibi. A semiquantitative uptake score was used and scintigraphic findings were correlated with clinical and laboratory data., Results: All the MGUS patients showed a negative (99m)Tc-sestamibi scan. Among the 32 MM patients (25 with active disease and 7 in clinical remission) 24 showed a positive scan, while 8 presented only a physiologic uptake of the tracer. The uptake score correlated significantly with all the most relevant clinical variables. In the follow-up of 8 MM patients treated with high-dose chemotherapy (99m)Tc-sestamibi closely paralleled the activity of myeloma bone disease. Comparison with X-ray skeletal survey showed discordant results in 14 out of the overall 56 scans obtained (27%), with 10 cases of negative (99m)Tc-sestamibi scans but lytic bone lesions revealed by X-ray (7 of them were in clinical remission), and 4 negative X-ray surveys in patients with positive (99m)Tc-sestamibi scans. Overall sensitivity and specificity of (99m)Tc-sestamibi scintigraphy in detecting myeloma bone disease were 90% and 88%, respectively., Interpretation and Conclusions: This study provides additional evidence indicating that (99m)Tc-sestamibi scintigraphy closely reflects myeloma disease activity in bone marrow, with very high sensitivity and specificity. (99m)Tc-sestamibi scintigraphy is therefore suggested as a reliable new tool for the staging and follow-up of myeloma bone disease.

Background: Elderly patients with acute myeloid leukemia (AML) those refractory to induction chemotherapy and those with so-called secondary leukemia have unfavorable prognoses and require innovative therapeutic approaches. Fludarabine allows an increased accumulation of Ara-CTP in leukemic cells and inhibits DNA repair mechanisms; therefore its association with Ara-C and mitoxantrone results in a synergistic effect., Materials and Methods: From May 1993 to February 1996, fludarabine-containing regimens (FLAG and FLANG) were employed as induction therapy in 51 high-risk AML patients. Diagnosis of AML in 22 patients was preceded by a myelodysplastic syndrome lasting more than six months; 8 of the 29 de novo AML cases (28%) were refractory to previous chemotherapy, 9 (31%) were treated for early relapse, 12 (41%) presented poor prognostic factors at diagnosis. The median age was 64 (range 33-76) years and the FAB subtypes were the following: M0 3, M1 5, M2 28, M4 7, M5 8. Forty-eight per cent of patients showed poor prognosis chromosomal abnormalities. FLAG (24 patients) consisted of both fludarabine 30 mg/sqm over 30 minutes followed 4 hours later by Ara-C 2 g/sqm over 4 hours (for 5 days) and G-CSF 300 micrograms/day administered 12 hours before fludarabine, for a total of 5 doses. FLANG (27 patients) had a shorter duration (3 days), reduced Ara-C dosage (1 g/sqm) and administration of mitoxantrone (10 mg/sqm) at the end of Ara-C infusion., Results: Recovery of both neutrophils (PMN > 0.5 x 10(9)/L) and platelets (Plt > 20 x 10(9)/L) required a median of 16 days from the end of therapy. Overall, 30 patients (59%) achieved CR, 6 (11%) PR and 10 (20%) were refractory; 5 (10%) experienced early death (cerebral hemorrhage or infection). The length of complete response ranged from 2 to 26 months with a median follow-up of 8 months. De novo and secondary AML registered 62 and 54% CR rates, respectively. Eight out of 10 patients refractory to conventional schemes achieved CR (80%) but only 3 out of 10 treated for relapse obtained CR (30%)., Conclusions: FLAG and FLANG showed similar activity and toxicity while proving to be highly effective and relatively well-tolerated treatments for high-risk de novo AML. Secondary leukemias seemed to be responsive as well, but the presence of an unfavorable karyotype alteration lowered the response rate.

The long-term effects of recombinant human erythropoietin (rhEPO) administration in two consecutive cases of paroxysmal nocturnal hemoglobinuria (PNH) with severe anemia are reported. In both patients, a 68-year-old woman and a 66-year-old man, a diagnosis of PNH was made on the basis of severe macrocytic anemia associated with hemoglobinuria, hemosiderinuria and positivity for the sucrose and Ham tests. Subcutaneous treatment with rhEPO, 150 U/Kg body weight daily, was followed in both cases by a progressive increase in hemoglobin concentrations, which thereafter were maintained above 10 g/dL with lower doses of rhEPO and without any relevant side effects for 32 and 29 months of continuous treatment, respectively. A clinical response was observed in spite of elevated baseline serum erythropoietin concentrations, appropriate to the degree of anemia in both patients. These results suggest that rhEPO may be appropriately and safely used in the long-term correction of anemia associated with PNH, and that the response to the pharmacologic doses of rHEPO administered was not dependent on the level of endogenous erythropoietin.

Background: Despite the fact that granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) are increasingly used in clinical practice, little is known of their endogenous production, especially in myeloproliferative disorders such as chronic myelogenous leukemia (CML)., Methods: In order to define serum levels of GM-CSF and G-CSF in subjects affected by CML, the sera of 17 patients with CML in chronic phase treated either with hydroxyurea or interferon-alpha were tested by specific enzyme immunoassays. Fifteen age- and sex-matched healthy volunteers were used as normal controls., Results: Eight out of the 17 patients (44%) with CML showed detectable (> 3 pg/mL) serum levels of GM-CSF (range 3.9-55 pg/mL). Detectable levels (> 50 pg/mL) of G-CSF were observed in 9 of these patients (52%) (range 150-2,830 pg/mL). On the contrary, among the normal controls only one had detectable GM-CSF concentrations, and none had detectable G-CSF concentrations. The highest concentrations of both GM-CSF and G-CSF were seen in patients with the highest white blood cell counts, although a linear correlation between the levels of these growth factors and the number of circulating leukocytes was not demonstrated., Conclusions: Our data indicate that significant amounts of both endogenous GM-CSF and G-CSF are detectable in the serum of a substantial percentage of patients with CML in chronic phase. The pathophysiological meaning of this finding remains to be determined.

Background: Several methods for the recruitment of circulating progenitor cells (CPC) to be used for hemopoietic rescue after myeloablative therapy have been described. The present study was designed to verify the effectiveness and safeness of one of such procedures, involving the administration of high-dose cyclophosphamide (HD-CTX) and granulocyte-macrophage colony-stimulating factor (GM-CSF)., Methods: Eight tumor patients were treated with HD-CTX (7 g/m2), followed by GM-CSF (7 mcg/Kg/day, continuous infusion) from day +2 to the completion of leukocyte recovery, when aphereses for CPC harvesting were performed. CPC were evaluated by clonogenic assay for granulocyte-macrophage colony-forming units (CFU-GM), megakaryocyte colony-forming units (CFU-Meg) and erythrocyte burst-forming units (BFU-E) before therapy as well as during the hemopoietic recovery., Results: In each patient, a significant increase of trilineage CPC was observed, at a mean of 14 days from HD-CTX, with peak increment of 224, 268 and 230-fold for CFU-GM, CFU-Meg and BFU-E respectively. The mean duration of leukocyte count < or = 0.5 x 10(9)/l was 6.6 days, with severe thrombocytopenia (grade 4 WHO) lasting 2.8 days in 5 patients. GM-CSF infusion was well tolerated without any need for dose reduction or discontinuation., Conclusion: The administration of HD-CTX and GM-CSF induces a significant enhancement of CPC including CFU-Meg other than CFU-GM and BFU-E. The procedure is suitable for the recruitment of CPC in patients with CTX sensitive tumors.