T regulatory cells mediate immunosuppresion by adenosine in peripheral blood, sentinel lymph node and TILs from melanoma patients.

T regulatory cells (Tregs), involved in tumour tolerance, can generate Adenosine by CD39/CD73 surface enzymes, which identify four Tregs subsets: CD39+CD73- nTregs, CD39+CD73+ iTregs, CD39-CD73+ oTregs and CD39-CD73- xTregs. In melanoma patients, increased Tregs levels are detected in peripheral blood (PB), sentinel lymph node (SLN) and tumour infiltrating lymphocytes (TILs), but Adenosine role was not investigated yet. We examined total Tregs and Adenosine subsets in PB, SLN and TILs from melanoma patients (n = 32) and PB from healthy donors (HD; n = 10) by flow cytometry. Total Tregs significantly increased in stage III-IV patients PB, in SLN and TILs, as compared to HD/stage I-II patients. Tregs subsets analyses showed that: 1) PB nTregs significantly increased in SLN and decreased in TILs; 2) iTregs significantly increased in stage III-IV patients PB and further significantly increased in SLN and TILs; 3) PB oTregs and xTregs significantly decreased in SLN and TILs. Patients clinical features did not significantly influence total Tregs, except SLN excision order. Results confirmed Tregs role in melanoma progression and indicate Adenosine generation as a novel escape mechanism, being nTregs and iTregs increased in PB/SLN/TILs.

Protective effects of the PARP-1 inhibitor PJ34 in hypoxic-reoxygenated cardiomyoblasts.

To clarify the role of poly(ADP-ribose)polymerase-1 (PARP-1) in myocardial ischemia-reperfusion injury, we explored some effects of PJ34, a highly specific inhibitor of this enzyme, in hypoxic-reoxygenated (HR) H9c2 cardiomyoblasts. Compared to the control, HR cells showed signs of oxidative stress, marked PARP-1 activation, NAD(+) and ATP depletion and impaired mitochondrial activity. HR cardiomyoblasts were affected by both necrosis and apoptosis, the latter involving the nuclear translocation of apoptosis-inducing factor. In HR cardiomyoblasts treated with PJ34, oxidative stress and PARP-1 activity were decreased, and NAD(+) and ATP depletion, as well as mitochondrial impairment, were attenuated. Above all, PJ34 treatment improved the survival of HR cells; not only was necrosis significantly diminished, but apoptosis was also reduced and shifted from a caspase-independent to a caspase-dependent pathway. These results suggest that PARP-1 modulation by a selective inhibitor such as PJ34 may represent a promising approach to limit myocardial damage due to post-ischemic reperfusion.

Use of CFDA-SE for evaluating the in vitro proliferation pattern of human mesenchymal stem cells.

BACKGROUND: Mesenchymal stem cells (MSC) are multipotent progenitors retaining the capability to undergo multilineage differentiation, mostly towards all the mesodermal cellular lineages. MSC growing under standard conditions are composed of two main subpopulations with a characteristic distribution in the morphologic flow cytometric scatter: RS (recycling stem) cells (small, agranular) and m (mature) MSC (large, moderately granular cells). METHODS: MSC obtained from BM of healthy donors and expanded in culture were characterized by evaluating both the expression of conventional markers and differentiation potential. We used CFSE, a lipophilic dye that is taken up by cell membranes, to investigate separately the proliferative activity of RS cells and mMSC subsets. RESULTS: With flow cytometric analysis, RS cells and mMSC showed nearly the same immunophenotypic pattern, even if a significantly smaller percentage of RS cells expressed some of the classic mesenchymal Ag. The RS cell fraction was confirmed to have a higher proliferative potential and such a feature was particularly evident under certain culture conditions. DISCUSSION: CFSE has been shown as a reliable method for studying the proliferative activity of MSC subpopulations identified by flow cytometric analysis. The acquisition parameter strategy is crucial for the accuracy of the analysis.

Growth inhibition and differentiation of human breast cancer cells by the PAFR antagonist WEB-2086.

WEB-2086 -- an antagonist of platelet-activating factor receptor (PAFR) with known anti-inflammatory, antiangiogenic and antileukaemic properties -- also proved to inhibit the proliferation in human solid tumour cell lines of different histology, and with much higher efficacy than in normal fibroblasts. A detailed analysis of WEB-2086 anticancer activity was then performed focusing on breast adenocarcinoma MCF-7 and MDA-MB-231 cells. WEB-2086-treated cells, either expressing (MCF-7) or unexpressing (MDA-MB-231) the oestrogen receptor (ER)alpha, underwent a dose-dependent growth arrest (IC(50)=0.65+/-0.09 and 0.41+/-0.07 mM, respectively) and accumulation in G(0)-G(1) phase. WEB-2086 also induced morphological and functional changes typical of mature mammary phenotype including (i) cell enlargement and massive neutral lipid deposition (best accomplished in MCF-7 cells); (ii) decrease in motility and active cathepsin D levels (mainly observed in highly invasive MDA-MB-231 cells). The expression of ERalpha was neither increased nor reactivated in treated MCF-7 or MDA-MB-231 cells, respectively. WEB-2086-induced differentiation in breast cancer cells involved the upregulation of PTEN, a key tumour suppressor protein opposing tumorigenesis, and was apparently independent of p53, PAFR, peripheral benzodiazepine receptor and ERalpha status. Overall, WEB-2086 can be proposed as an effective antiproliferative and differentiative agent with interesting translational opportunities to treat breast cancers in support to conventional chemotherapy.

VEGF inhibition and cytotoxic effect of aplidin in leukemia cell lines and cells from acute myeloid leukemia.

BACKGROUND: Aplidine (APL) is a marine depsipeptide isolated from the Mediterranean tunicate Aplidium albicans that is under clinical phase II development. In contrast to the lack of bone marrow toxicity reported in phase I/II studies, it has been shown to induce cytotoxicity at very low concentration against lymphoblastic leukemia blast, as well as having an impact in the vascular endothelial growth factor (VEGF)/VEGF receptor 1 loop. PATIENTS AND METHODS: To confirm these findings we investigated APL-related VEGF inhibition and its cytotoxic effect on myeloid leukemic cells lines (K-562, HEL and HL60) and fresh leukemia blasts derived from 30 patients with acute myeloid leukemia (AML). The conventional active 4-demetoxi-daunorubicin (idarubicin; IDA) was included as a positive control. RESULTS: APL was found to be significantly (P<0.001) more active than IDA in obtaining 50% growth-inhibition in K-562, HEL and HL60 cell lines. Results obtained with AML blast cells were super imposible. ID(50) ranged from 0.024 to 0.610 microM for IDA (0.200+/-0.176) and from 0.001 to 0.108 microM for APL (0.020+/-0.031). Annexin V tests and cell cycle analysis performed on cell lines confirmed the stronger citotoxic capability of APL as apoptotic inducer and as a G(1) blocker. The inhibitory effects of APL on VEGF release and secretion have been confirmed by ELISA tests performed on HEL: the VEGF concentration in cell surnatant was reduced from 169 to 36 pg/ml after 24 h of exposure to a pharmacological concentration of APL. CONCLUSIONS: APL harbors a strong in vitro antileukemic activity at a concentration achievable in patients at non-myelotoxic doses. Our data also support the notion of an impact on VEGF secretion. Clinical studies with this new marine-derived compound in relapsed/resistant leukemia are underway.

Selective ex vivo expansion of cytomegalovirus-specific CD4+ and CD8+ T lymphocytes using dendritic cells pulsed with a human leucocyte antigen A*0201-restricted peptide.

Adoptive transfer of ex vivo-generated cytomegalovirus (CMV)-specific T lymphocytes may be effective in preventing CMV disease in allogeneic haematopoietic stem cell transplantation (HSCT) recipients. We developed a procedure for expansion of CMV-specific T lymphocytes based on the antigen-presenting function of donor dendritic cells (DCs), pulsed with a human leucocyte antigen A*0201-restricted pp65 nonamer peptide. CMV-specific T lymphocytes were identified following induction of interferon gamma (IFN-gamma) secretion prompted by peptide exposure. Both CD8+ and CD4+ CMV-specific T lymphocytes were selectively produced in these cultures and showed CMV-restricted cytotoxicity. The simultaneous and selective expansion of CD4+ and CD8+ CMV-specific lymphocytes might be instrumental for more efficient in vivo function of infused CMV-specific lymphocytes.

Ligands of peroxisome proliferator-activated receptor gamma modulate profibrogenic and proinflammatory actions in hepatic stellate cells.

BACKGROUND & AIMS: Proliferation and migration of hepatic stellate cells (HSCs) and expression of chemokines are involved in the pathogenesis of liver inflammation and fibrogenesis. Peroxisome proliferator-activated receptor (PPAR)-gamma is a receptor transcription factor that controls growth and differentiation in different tissues. We explored the effects of PPAR-gamma agonists on the biological actions of cultured human HSCs. METHODS: HSCs were isolated from normal human liver tissue and used in their myofibroblast-like phenotype or immediately after isolation. Activation of PPAR-gamma was induced with 15-deoxy-Delta(12, 14)-prostaglandin J(2) or with troglitazone. RESULTS: PPAR-gamma agonists dose-dependently inhibited HSC proliferation and chemotaxis induced by platelet-derived growth factor. This effect was independent of changes in postreceptor signaling or expression of c-fos and c-myc and was associated with inhibition of cell cycle progression beyond the G(1) phase. Activation of PPAR-gamma also resulted in a complete inhibition of the expression of monocyte chemotactic protein 1 at the gene and protein levels. Comparison of quiescent and culture-activated HSCs revealed a marked decrease in PPAR-gamma expression in activated cells. CONCLUSIONS: Activation of PPAR-gamma modulates profibrogenic and proinflammatory actions in HSCs. Reduced PPAR-gamma expression may contribute to confer an activated phenotype to HSCs.

Identification and characterization of a bipotent (erythroid and megakaryocytic) cell precursor from the spleen of phenylhydrazine-treated mice.

We have identified a cell population expressing erythroid (TER-119) and megakaryocyte (4A5) markers in the bone marrow of normal mice. This population is present at high frequency in the marrows and in the spleens involved in the erythroid expansion that occurs in mice recovering from phenylhydrazine (PHZ)-induced hemolytic anemia. TER-119(+)/4A5(+) cells were isolated from the spleen of PHZ-treated animals and were found to be blast-like benzidine-negative cells that generate erythroid and megakaryocytic cells within 24-48 hours of culture in the presence of erythropoietin (EPO) or thrombopoietin (TPO). TER-119(+)/4A5(+) cells represent a late bipotent erythroid and megakaryocytic cell precursors that may exert an important role in the recovery from PHZ-induced anemia. (Blood. 2000;95:2559-2568)

Induction of apoptosis by monosaccharide butyrate stable derivatives in chronic lymphocytic leukemia cells.

BACKGROUND AND OBJECTIVE: Different therapeutic approaches are needed to restore apoptotic mechanisms in CLL cells, as present ones are not successful. We assessed the apoptotic effects of stable butyrate derivatives on CLL lymphocytes: in these molecules a mannose molecule is bound as ester to one-five butyrate moieties, conferring pharmacological stability to the pro-drugs which are able to induce apoptosis in primary AML blasts. DESIGN AND METHODS: Peripheral blood samples obtained from 17 patients with typical B-CLL were cultured in the presence of 0.5-1mM D1 (O-n-butanoyl-2, 3-O-isopropylidene-a-D-mannofuranoside), F1 (1-O-n-butanoyl-2, 3-O-isopropylidene-D,L-xylitol) and G1 (1-O-n-butanoyl-D,L-xylitol) derivatives for 4 days and equimolar sodium butyrate as comparison. After culture, apoptosis was evaluated by cell morphology, cellular DNA content, pattern of DNA fragmentation, annexin V exposure on cell membrane, and cell cycle parameters. Bcl2, bax, and fas oncogene expression were also evaluated by the APAAP method. RESULTS: The addition to cell cultures of D1 or F1 or G1 butyrate monosaccharides as well as sodium butyrate 0.5 and 1 mM determined to different extents an increase in the percentage of apoptotic cells in all CLL samples, relatively to the method and butyrate molecule added in culture. Heterogeneity in CLL cell sensitivity to the three butyrates was observed. Up to 60-68% apoptotic bodies were present in treated cultures after exposure to D1 0.5-1 mM, 60-72% after F1 0.5-1 mM and 48-60% after G1 0.5-1 mM. Comparison of untreated versus treated cultures yielded important significance (p< 0.001). At DNA content analysis, analyzed by flow cytometry, apoptotic events were accounting for up to 70-77% of D1-treated and 68-74% of F1-treated CLL cells at 0.5 and 1 mM concentrations (p= 0. 0001, vs controls 0-39%), and for 72-81% of G1 (0.5-1 mM) treated cells (overall, p=0.005). Cell cycle parameters were not altered by addition of butyrates, but expression of Annexin V was greatly enhanced. In a limited number of CLL cases fas, bcl2/bax ratio was analyzed and found unmodified. INTERPRETATION AND CONCLUSIONS: Monosaccharide butyrate stable derivatives are potent inducers of primary CLL cell apoptosis, both in untreated and alkylating agent pre-treated cases. Our results suggest that the apoptotic pathways elicited by butyrate in CLL lymphocytes are direct, specific and most probably do not involve bcl2/bax. Pro-apoptotic agents like the stable monosaccharide butyrate derivatives here studied could bring more insights into CLL biology and resistance to apoptosis, and possibly originate alternative treatments for CLL.

Coexpression of erythroid and megakaryocytic genes in acute erythroblastic (FAB M6) and megakaryoblastic (FAB M7) leukaemias.

There is evidence to suggest a close relationship between the erythroid and megakaryocytic lineages. Using RT-PCR, we evaluated the coexpression of erythroid and megakaryocytic genes in blasts from 25 acute myeloid leukaemia (AML) cases (FAB M1-M7) and three unclassifiable leukaemias with trilineage dysplasia (trilineal AML). All FAB M6 and M7 and trilineal leukaemias expressed mRNAs for alpha-globin, glycoprotein IIb (GpIIb), erythropoietin receptor (Epo-R) and thrombopoietin receptor (c-mpl), but not for myeloperoxidase (MPO) which in contrast was expressed in the other FAB-subtype leukaemias. These data support the hypothesis that blasts from M7 and M6 leukaemias may derive from (or represent) a common progenitor cell with resident bipotentiality towards the megakaryocytic and erythrocytic lineages.

Erythropoietin upregulates the expression of its own receptor in TF-1 cell line.

In the erythroleukemia cell line TF-1, recombinant human erythropoietin (rHEpo), but not c-kit ligand, enhanced the number of cells expressing the erythropoietin receptor (EpoR), as measured by flow-cytometric analysis of binding of the biotin-labeled Epo. Moreover, 125I-Epo binding and Scatchard analyses, indicated that TF-1 cells, maintained in standard conditions with IL-3, and those stimulated with c-kit ligand, bear a single class of EpoR. On the other hand, cells cultured in the presence of rHEpo had a higher number of receptors than IL-3 or c-kit ligand-stimulated cells, and had two binding sites with different affinities for the ligand. EpoR mRNA expression was higher in cells exposed to rHEpo than in IL-3 or c-kit-stimulated cells. This difference may have been dependent on either a higher level of transcription or an increased stability of mRNA. The observed changes of EpoR in rHEpo-stimulated TF-1 cell line could cooperate, together with the alteration of the gene (3' end deletion), in the occurrence of the erythroleukemic process. Changes induced in EpoR by rHEpo were not accompanied by an increase in the expression of glycophorin A or globin chain mRNAs. This may suggest that rHEpo is unable to induce erythroid differentiation in TF-1 cells. The results also indicate that this cell line could be a model for the investigation of the role of transcription factor(s) in the expression of EpoR, and for the study of the mechanism(s) underlying the changes in the number and affinity of the cell receptors.

Idarubicin in induction treatment of acute myeloid leukemia in the elderly.

BACKGROUND AND OBJECTIVE: The best approach to treatment of acute myeloid leukemia (AML) in elderly patients remains controversial. Intensive chemotherapy is the treatment of choice in selected patients, but age related changes might affect the pharmacokinetics of antineoplastic agents resulting in enhanced toxicity. We report our experience in elderly patients treated with idarubicin at attenuated doses plus cytarabine and etoposide. METHODS: Sixty-six AML patients, median age 66, with progressive disease and high tumor burden received idarubicin 8 mg/sqm i.v. d 1,3,5; cytarabine 200 mg/sqm by continuous i.v. infusion d 1-7; etoposide 60 mg/sqm i.v. d 1-5. A second course with the same drugs was planned irrespective of complete remission (CR) achievement. No consolidation was given; 44% had a documented preexisting myelodysplasia, 45% had a documented preexisting myelodysplasia, 45% presented with fever. Promyelocytic leukemias were excluded. RESULTS: Thirty-five patients (53%) achieved CR and 9 PR for an overall response rate of 67%. Nine of them (13%) died early or during the aplastic phase. Preexisting myelodysplasia had no significant impact on CR achievement. Resistant disease was associated with CD7 phenotype and unfavorable karyotype. Overall survival and disease free survival were 14 and 13 months, respectively. The major toxicity consisted of infectious complications (WHO > 2 in 24% of patients). Six patients died for infection, 2 for heart failure, 1 for pulmonary embolism. INTERPRETATION AND CONCLUSIONS: This induction regimen with attenuated doses of idarubicin is feasible and effective, but long-term survival remains an unresolved problem. Alternative post remission approaches are advisable in the aim of improving the remission duration.

Severe hypoxia enhances the formation of erythroid bursts from human cord blood cells and the maintenance of BFU-E in vitro.

Incubation in severe hypoxia (1% oxygen) increased the number of erythroid bursts generated from full-term CD34+, or premature mononucleated, human cord blood (CB) cells, in semisolid cultures containing stem cell factor (SCF), interleukin (IL)-3 and erythropoietin (EPO). Severe hypoxia also enhanced the maintenance of erythroid burst-forming units (BFU-E) in CB cell liquid cultures. These positive effects of hypoxia on the maintenance and cloning efficiency of BFU-E did not extend to the other progenitors assayed. Hypoxia, on the other hand, markedly reduced the size and level of hemoglobinization of bursts and, in liquid cultures, suppressed the growth factor-stimulated numerical increase in BFU-E and inhibited the expression of CD36, a marker of erythroid colony-forming units and maturing erythroid precursors. However, when transferred to clonal assays incubated in air, cells from liquid cultures incubated in hypoxia or in air generated fully expanded and hemoglobinized bursts, suggesting that in hypoxia the clonogenic potential of BFU-E was maintained and the development of erythroid clones reversibly inhibited. These results indicate that hypoxia inversely regulates two subsequent phases of erythropoiesis, i.e., it enhances the maintenance of BFU-E and the early development of erythroid clones but inhibits the terminal expansion and maturation of these clones. The cloning of CB cells selected for CD34 positivity, when compared with that of the total population of mononucleated CB cells, revealed that the early development of erythroid bursts was either hypoxia-enhanced or hypoxia-insensitive, reflecting the existence of two different types of BFU-E. Hypoxia-enhanced BFU-E are relatively immature, are maintained in hypoxia but not in air, and account for a large part of CD34+ BFU-E and for a high percentage of the BFU-E in premature CB. Hypoxia-insensitive BFU-E are mostly CD34- and are largely predominant in full-term CB, and most probably correspond to a more mature type of BFU-E.

[Long-term captopril therapy in asymptomatic patients with severe chronic aortic insufficiency]. / Terapia a lungo termine con captopril in pazienti asintomatici con insufficienza aortica cronica di grado severo.

BACKGROUND: Clinical history of patients with severe chronic aortic regurgitation is characterized by a long period without any symptom, although the left ventricle enlarges progressively. The administration of oral vasodilators could reduce ventricular enlargement or its progression, delaying the development of myocardial dysfunction and/or the need for valvular surgery. OBJECTIVES: To verify the efficacy of long-term captopril therapy to reduce left ventricular mass and dimensions in patients with severe chronic aortic regurgitation. METHODS: This is a prospective echocardiographic study in which each individual patient is considered his own control case. Eleven asymptomatic patients with severe chronic aortic regurgitation in sinus rhythm, who had an ejection fraction greater than 50% and were not taking cardiovascular drugs, were orally administered captopril at the maximum tolerated dosage (127 +/- 13 mg/day). Follow-up lasted for 24 +/- 3 months. RESULTS: Left ventricular telediastolic diameter decreased from 69 +/- 5 to 61 +/- 3 mm (p < 0.01), telesystolic diameter decreased from 48 +/- 5 to 41 +/- 4 mm (p < 0.01); ejection fraction increased from 56 +/- 4 to 61 +/- 3% (p < 0.001); myocardial mass decreased from 208 +/- 32 to 174 +/- 27 g/m2 (p < 0.01), and mean wall stress from 264 +/- 35 to 203 +/- 25 mmHg (p < 0.001). All variations were still significant at 6 months. CONCLUSIONS: These results suggest that captopril has a favourable effect on left ventricular mass, dimensions and load conditions, and could favourably influence the natural history of chronic aortic regurgitation. The efficacy of medical treatment can be verified through serial echocardiographic study.

Megakaryocyte-like increase in ploidy of Friend's erythroleukemia cells induced to endoreplication by colcemid.

Previous work from this laboratory has shown that Friend's murine erythroleukemia cells (MELCs) express some bio-chemical traits of the megakaryocytic lineage. The supposed mixed erythroid/megakaryocytic nature of these cells has been investigated further by challenging MELCs with the antimicrotubule agent colcemid. This compound, at the concentration of 40 nM, was found to induce a striking arrest of cell growth without significant effects on viability. At the same time, the bulk of treated MELCs underwent a large increase in size to contain, after 3 days, as much as 4 times more proteins and 5 times more DNA than controls. As shown by high rates of 3H-thymidine incorporation, increase in DNA content was the result of active synthesis without completion of intervening mitosis according to a process that closely resembled endoreplication. Eventually, colcemidinduced MELCs presented multilobed nuclei and were arranged into discrete ploidy groups containing up to 16 N levels of DNA. Moreover, upon colcemid addition, MELCs initiated a polyploid response that was shown to continue, even in the absence of the inducer, to yield cells that became strongly positive for acetylcholinesterase (AChE) in the late stages of culture. These effects were compatible with a colcemid-induced commitment of MELCs to megakaryocyte differentiation, for which these cells seemed to be definitely programmed. The expression of megakaryocyte features in MELCs provided further evidence for the bipotentiality (erythroid/megakaryocytic) of this model.

Identification and conditions for selective expression of megakaryocytic markers in Friend erythroleukemia cells.

Friend murine erythroleukemia cells (MELCs) have been reevaluated in terms of their nature and potential pathways of differentiation. MELC induced with 5 mmol/L hexamethylene bisacetamide (HMBA), in addition to expression of known markers of the erythroid phenotype, were also found to exhibit traits of the megakaryocytic lineage. Erythroid differentiation was shown by the typical synthesis and accumulation of hemoglobin (Hb); megakaryoblastoid differentiation of MELCs upon induction was shown by increased specific activity of acetylcholinesterase (AChE). Incubation of MELCs with 5 mmol/L HMBA in RPMI supplemented with 1% fetal calf serum (FCS) (instead of the usual 5%), induced cells to selectively express high levels of AChE (up to approximately 170 mU/mg protein) with little activation of Hb synthesis (less than 5% B+ cells). The increase in AChE levels was a general phenomenon affecting the whole cell population and approached its maximum within 3 days of incubation with the inducer. Subsequently, MELCs become committed to terminal division, undergoing growth arrest and expression of the megakaryocytic phenotype even after the removal of HMBA. There were no appreciable changes of basal AChE levels in MELCs that were either made resistant to HMBA or treated with 0.1 mmol/L hemin that activated differentiated erythroid function without commitment. Phorbol 12-myristate 13-acetate (PMA), known to repress induced Hb synthesis in these cells, did not prevent the full increase in AChE when incubated with MELCs 2 days before HMBA addition. HMBA-induced MELCs always underwent AChE increase that was more or less pronounced depending on the low or high serum content in culture, respectively. Conversely, Hb expression was permitted only when MELCs were transferred in the late phase or at the end of commitment from low to high serum media. Variations of FCS content in culture media proved to be a simple and reliable approach to change the MELC response to inducers and to modulate expression of either megakaryocytic or mixed erythromegakaryocytic phenotype. These findings suggested that MELC might be considered, at least, as a bipotential model of differentiation to be used for studies on regulation of either megakaryocytic or erythroid markers and on competition between the two hematopoietic lineages. In this regard, it was intriguing that AChE levels attained under selective induction (low serum) were always higher than under conditions allowing coexpression of both AChE and Hb (high serum). Moreover, MELCs were also found to bind the specific rat-antimouse platelet monoclonal antibody 4A5.(ABSTRACT TRUNCATED AT 400 WORDS)

Low-dose cytosine arabinoside in patients with acute myeloid leukemia not eligible for standard chemotherapy.

The results of treatment with low dose cytosine arabinoside (LDARA-C) in 131 AML patients ineligible for standard regimens were analyzed retrospectively. Eighty-seven were previously untreated, 25 were refractory to conventional chemotherapy and 19 were relapsed patients. The median age was 66 years (15-84). An antecedent hematological disorder (AHD) was documented in half of the patients. Overall, 22 (17%) achieved complete remission, 14 (11%) partial remission, 77 (59%) had resistant leukemia and 18 died during induction. Median disease free survival was 57 weeks and median survival, for the 87 previously untreated patients, was 22.5 weeks. The prognostic value of initial parameters was analyzed for response. Bone marrow cellularity was the only significant factor. We observed 33% vs 81% (p < 0.01) of responses in patients with normo-hypercellular and hypocellular marrow, respectively. Accordingly, there was a trend to more responses in patients with leukocyte counts of less than 10 x 10(9)/L. M4-M5 FAB subtypes were frequently resistant to LDARA-C, resulting in a lower response rate compared to M0-M2 (18% vs 32%). Other parameters, including age, sex, hemoglobin, platelet count, AHD and fever at diagnosis, had no prognostic value. Our findings suggest that LDARA-C may be an effective treatment for some patients who are not eligible for first line conventional chemotherapy. However, this schedule is not advised in patients with monocytic leukemia or those with an hypercellular marrow.

Attenuated-dose idarubicin in acute myeloid leukaemia of the elderly: pharmacokinetic study and clinical results.

AML in the elderly is characterized by intrinsic biological features implying an enhanced chemoresistance. Intensive chemotherapy should be the treatment of choice, but the standard doses could induce unacceptable rates of aplastic deaths. We evaluated the efficacy of an induction protocol with attenuated-dose idarubicin (IDA) 8 mg/m2 for 3 d plus cytarabine and etoposide in 26 AML patients aged > 60. 18 patients (69%) achieved CR, five (19%) were non-responders and three (12%) died during induction. To compare the pharmacokinetics of IDA between elderly and young patients, we assayed daily the serum level of the drug and of its metabolite (idarubicinol, IDAol) in a group of eight elderly patients who received a dose of 8 mg/m2 (group A) and in a group of nine younger AML patients treated with 12 mg/m2 (group B). The apparent terminal half-life of IDAol was significantly longer in the elderly than in the younger patients (mean half-life 59.7 h versus 41.4 h, P < 0.05). The values of the area under the serum concentration curve of IDAol indicated that the two patient groups received a very similar exposure to the drug despite the different doses. In conclusion, this protocol, based on attenuated doses of IDA, compares well with the results obtained previously in similar age-matched patient series.

[Restrictive cardiomyopathies]. / Le cardiomiopatie restrittive.

The restrictive cardiomyopathies are the least common of the 3 major categories of cardiomyopathic disorders seen in Western countries. According to the report of the WHO/ISFC Task Force the term restrictive cardiomyopathy applies to only 2 conditions: endomyocardial fibrosis and Loeffler endocarditis while many specific myocardial diseases can develop a restrictive pathophysiologic profile along their natural history. During the last decade this topic has received 2 main contributions: the identification of a common pathophysiologic ground linking Loeffler endocarditis and endomyocardial fibrosis and the identification of the so-called idiopathic restrictive cardiomyopathy. This condition, defined as a myocardial disease with restrictive physiology, unknown etiology and without histological evidence of infiltrative or storage diseases, appears to be the single most frequent type of restrictive cardiomyopathy in Western countries. A revision of the current classification of cardiomyopathies and particularly of restrictive myocardial disease is necessary.

Mixed acute leukemia with genotypic lineage switch: a case report.

Morphologically well classifiable leukemias can reveal a mixed phenotype. A case of acute myeloid leukemia (CD13, CD33, CD14, CD11b) which at presentation showed a co-expression of B-lymphoid markers (CD19, CD10, CD20), at the time of the first relapse revealed a morphologic, phenotypic and genotypic switch of the blasts to a purely lymphoid form. Analysis of the immunoglobulin (Ig) H chain locus and of the T-cell receptor (TCR) genes showed at diagnosis a germline configuration of the IgH, TCR beta and tau genes, and a deletion of the TCR delta gene at the second chromosome. At relapse, monoclonal rearrangements of the IgH, TCR tau, and TCR delta were detected. At a subsequent relapse, the blasts re-expressed myeloid morphologic features and myeloid-associated antigens, while they retained the same rearranged configuration of the IgH and TCR beta and delta genes. The TCR delta gene configuration, which links each phase of the disease, may represent an early pathogenetic event and makes the emergence of a second malignancy unlikely. Each phenotypic change occurred after anti-myeloid and anti-lymphoid oriented chemotherapy. The close correlation between the progressive acquisition of different phenotypes and the switch at the genomic level represent the peculiar features of this unusual case.