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Michele Baccarani

Publications and source records attributed to Michele Baccarani.

At least 19 recordsLinked to original sources
PubMed2007

Modulation of tryptophan catabolism by human leukemic cells results in the conversion of CD25- into CD25+ T regulatory cells.

Indoleamine 2,3-dioxygenase (IDO) is a novel immunosuppressive agent expressed in some subsets of normal and neoplastic cells, including acute myeloid leukemia (AML) cells. Here, we show that IDO expression correlates with increased circulating CD4+CD25+FOXP3+ T cells in patients with AML at diagnosis. In vitro, IDO+ AML cells increase the number of CD4+ CD25+ T cells expressing surface CTLA-4 and FOXP3 mRNA, and this effect is completely abrogated by the IDO inhibitor, 1-methyl tryptophan (1-MT). Purified CD4+CD25+ T cells obtained from coculture with IDO+ AML cells act as T regulatory (T(reg)) cells because they do not proliferate, do not produce interleukin (IL)-2, and inhibit naive T-cell proliferation. Coculture with IDO+AML cells results in the conversion of CD4+CD25- into CD4+CD25+ T cells, which is completely abrogated by 1-MT. Moreover, in mice, intrasplenic injection of IDO+ leukemia/ lymphoma A20 cells induces the expansion of bona fide T(reg) cells by conversion of CD4+CD25- T cells; this effect is counteracted by 1-MT treatment. These data indicate that AML cells induce T-cell tolerance by directly converting CD4+CD25- T cells into CD4+CD25+ T(reg) cells through an IDO-dependent mechanism.

Adult↗
PubMed2007

Imatinib plus steroids induces complete remissions and prolonged survival in elderly Philadelphia chromosome-positive patients with acute lymphoblastic leukemia without additional chemotherapy: results of the Gruppo Italiano Malattie Ematologiche dell'Adulto (GIMEMA) LAL0201-B protocol.

Thirty elderly (> 60 years) Philadelphia chromosome-positive (Ph(+)) patients with acute lymphoblastic leukemia (ALL) received imatinib, 800 mg daily, associated to steroids without further chemotherapy as frontline treatment. Median age was 69 years (range, 61-83 years). Twenty-nine patients were evaluable for response and all of them obtained a hematologic complete remission, with a median BCR-ABL reduction of 2.9 and 2.0 logs in p190(+) and p210(+) cases, respectively. Most of the induction treatment did not require admission of the patients. No major toxicities occurred and the treatment was well tolerated. Median survival from diagnosis was 20 months. This study shows that elderly Ph(+) patients with ALL-often considered eligible only for palliative treatment strategies-may benefit from an imatinib-steroids protocol, which does not require chemotherapy nor a long hospitalization, is feasible, highly active, and associated with a good quality of life.

Aged↗
PubMed2007

Case-control study of multidrug resistance phenotype and response to induction treatment including or not fludarabine in newly diagnosed acute myeloid leukaemia patients.

One hundred and six patients aged </=60 years with newly diagnosed acute myeloid leukaemia (AML) treated with fludarabine-based regimens (cases) were matched with 106 AML patients treated with conventional non-fludarabine-based regimens (controls). The cases and controls were matched by expression of the multidrug resistance P-glycoprotein (MDR-Pgp), measured by flow cytometry as mean fluorescence index (MFI), cytogenetics, and age. The complete remission (CR) rate of the cases was 61% among the MDR-Pgp-positive (pos(ve)) patients (MFI >/= 6) vs. 75% among the MDR-Pgp-negative (neg(ve)) ones (MFI < 6) (P = 0.16). Conversely, in the controls, the CR rate was 44% among the MDR-Pgp-pos(ve) patients vs. 67% among the MDR-Pgp-neg(ve) ones (P = 0.02). The 4-year disease-free survival (DFS) and overall survival (OS) of MDR-Pgp-pos(ve) cases were significantly longer than those of MDR-Pgp-pos(ve) controls (DFS, 28.1% vs. 6.5%, P = 0.004; OS, 33.5% vs. 9.6%, P = 0.01). This difference was not found among the MDR-Pgp-neg(ve) patients. By univariate (P = 0.007) and multivariate (P = 0.007) analysis, the MDR-Pgp-pos(ve) phenotype was negatively correlated with CR and it emerged as the most important independent negative prognostic factor, after cytogenetics. Our study confirms the prognostic impact of the MDR phenotype in AML and strongly suggests fludarabine-based induction treatments as a promising strategy for MDR-Pgp-pos(ve) AML patients. In this setting of patients, large prospective randomised studies should be planned.

Acute Disease↗
PubMed2007

Impact of age on the outcome of patients with chronic myeloid leukemia in late chronic phase: results of a phase II study of the GIMEMA CML Working Party.

To assess the effect of age on response and compliance to treatment in patients with chronic myeloid leukemia (CML) we performed a sub-analysis within a phase II trial of the GIMEMA CML Working Party (CML/002/STI571). Since the WHO cut-off age to define an older patient is 65 years, among the 284 patients considered, we identified 226 (80%) younger patients (below 65 years) and 58 (20%) older patients (above 65 years) before starting imatinib. Response rates (hematologic and cytogenetic) were lower in the older age group but the probabilities of progression-free survival and overall survival (median observation time 3 years) were the same. Moreover, among complete cytogenetic responders, no differences were found in the level of molecular response between the two age groups. As might be expected, older patients experienced more adverse events, both hematologic and non-hematologic: this worsened compliance did not, however, prevent a long-term outcome similar to that of younger patients.

Adolescent↗
PubMed2007

A prospective comparison of 18F-fluorodeoxyglucose positron emission tomography-computed tomography, magnetic resonance imaging and whole-body planar radiographs in the assessment of bone disease in newly diagnosed multiple myeloma.

BACKGROUND AND OBJECTIVES: Bone lesions in multiple myeloma (MM) have been traditionally detected by whole body X-ray (WBXR) survey although magnetic resonance imaging (MRI) has become the gold standard for detecting MM involvement of the spine and pelvis. The aim of this study was to compare a new technique, positron emission tomography (PET) with 18F fluorodeoxyglucose (FDG) integrated with computed tomography (18F-FDG PET-CT), with MRI and WBXR for baseline assessment of bone disease in MM. DESIGN AND METHODS: We prospectively compared 18F-FDG PET-CT, MRI of the spine-pelvis and WBXR in a series of 46 patients with newly diagnosed MM. In 23 patients who received up front autologous transplantation, we also compared post-treatment PET-CT scans with MR images of the spine and pelvis. RESULTS: Overall, PET-CT was superior to planar radiographs in 46% of patients, including 19% with negative WBXR. In 30% of patients, PET-CT scans of the spine and pelvis failed to show abnormal findings in areas in which MRI revealed an abnormal pattern of bone marrow involvement, more frequently of diffuse type. In contrast, in 35% of patients PET-CT enabled the detection of myelomatous lesions in areas which were out of the field of view of MRI. By combining MRI of the spine- pelvis and 18F-FDG PET-CT, the ability to detect sites of active MM, both medullary and extramedullary, was as high as 92%. Following transplantation, 15 patients had negative PET-CT scans (including 13 with a very good partial response or at least a near complete response), but only 8 had normal MRI. INTERPRETATION AND CONCLUSIONS: MRI of the spine and pelvis still remains the gold standard imaging technique for the detection of bone marrow involvement in MM. 18F-FDG PET-CT provides additional and valuable information for the assessment of myeloma bone disease in areas not covered by MRI.

Adult↗
PubMed2006

Dasatinib induces complete hematologic and cytogenetic responses in patients with imatinib-resistant or -intolerant chronic myeloid leukemia in blast crisis.

The prognosis for patients with chronic myeloid leukemia (CML) in myeloid blast crisis (MBC) or lymphoid blast crisis (LBC) remains poor. Although imatinib can induce responses in a subset of these patients, resistance to the drug develops rapidly. Dasatinib is a novel, oral, multitargeted kinase inhibitor of BCR-ABL and SRC family kinases. After promising phase 1 results, we report the results of phase 2 clinical trials of dasatinib in patients with imatinib-resistant or -intolerant blast crisis CML (MBC, n = 74; LBC, n = 42). At the 8-month follow-up, dasatinib induced major hematologic responses (MaHRs) in 34% and 31% of MBC- and LBC-CML patients and major cytogenetic responses (MCyRs) in 31% and 50% of these patients, respectively. Most (86%) of these MCyRs were complete cytogenetic responses (CCyRs). Responses were rapid and durable: 88% and 46%, respectively, of MBC- and LBC-CML patients achieving MaHR had not experienced disease progression at the 8-month follow-up. Response rates were similar in patients with and without BCR-ABL mutations known to confer resistance to imatinib. Dasatinib was well tolerated. Nonhematologic adverse events were mild to moderate. Cytopenias were common and could be managed by dose modification. Dasatinib is highly active and produces hematologic and cytogenetic responses in a significant number of patients with imatinib-resistant or -intolerant MBC- and LBC-CML. These trials were registered at www.clinicaltrials.gov as #CA180006 and #CA180015.

Administration, Oral↗
PubMed2006

Contribution of ABL kinase domain mutations to imatinib resistance in different subsets of Philadelphia-positive patients: by the GIMEMA Working Party on Chronic Myeloid Leukemia.

PURPOSE: ABL kinase domain mutations have been implicated in the resistance to the BCR-ABL inhibitor imatinib mesylate of Philadelphia-positive (Ph+) leukemia patients. EXPERIMENTAL DESIGN: Using denaturing high-performance liquid chromatography and sequencing, we screened for ABL kinase domain mutations in 370 Ph+ patients with evidence of hematologic or cytogenetic resistance to imatinib. RESULTS: Mutations were found in 127 of 297 (43%) evaluable patients. Mutations were found in 27% of chronic-phase patients (14% treated with imatinib frontline; 31% treated with imatinib post-IFN failure), 52% of accelerated-phase patients, 75% of myeloid blast crisis patients, and 83% of lymphoid blast crisis/Ph+ acute lymphoblastic leukemia (ALL) patients. Mutations were associated in 30% of patients with primary resistance (44% hematologic and 28% cytogenetic) and in 57% of patients with acquired resistance (23% patients who lost cytogenetic response; 55% patients who lost hematologic response; and 87% patients who progressed to accelerated phase/blast crisis). P-loop and T315I mutations were particularly frequent in advanced-phase chronic myeloid leukemia and Ph+ ALL patients, and often accompanied progression from chronic phase to accelerated phase/blast crisis. CONCLUSIONS: We conclude that (a) amino acid substitutions at seven residues (M244V, G250E, Y253F/H, E255K/V, T315I, M351T, and F359V) account for 85% of all resistance-associated mutations; (b) the search for mutations is important both in case of imatinib failure and in case of loss of response at the hematologic or cytogenetic level; (c) advanced-phase chronic myeloid leukemia and Ph+ ALL patients have a higher likelihood of developing imatinib-resistant mutations; and (d) the presence of either P-loop or T315I mutations in imatinib-treated patients should warn the clinician to reconsider the therapeutic strategy.

Adolescent↗
PubMed2006

Five-year follow-up of patients receiving imatinib for chronic myeloid leukemia.

BACKGROUND: The cause of chronic myeloid leukemia (CML) is a constitutively active BCR-ABL tyrosine kinase. Imatinib inhibits this kinase, and in a short-term study was superior to interferon alfa plus cytarabine for newly diagnosed CML in the chronic phase. For 5 years, we followed patients with CML who received imatinib as initial therapy. METHODS: We randomly assigned 553 patients to receive imatinib and 553 to receive interferon alfa plus cytarabine and then evaluated them for overall and event-free survival; progression to accelerated-phase CML or blast crisis; hematologic, cytogenetic, and molecular responses; and adverse events. RESULTS: The median follow-up was 60 months. Kaplan-Meier estimates of cumulative best rates of complete cytogenetic response among patients receiving imatinib were 69% by 12 months and 87% by 60 months. An estimated 7% of patients progressed to accelerated-phase CML or blast crisis, and the estimated overall survival of patients who received imatinib as initial therapy was 89% at 60 months. Patients who had a complete cytogenetic response or in whom levels of BCR-ABL transcripts had fallen by at least 3 log had a significantly lower risk of disease progression than did patients without a complete cytogenetic response (P<0.001). Grade 3 or 4 adverse events diminished over time, and there was no clinically significant change in the profile of adverse events. CONCLUSIONS: After 5 years of follow-up, continuous treatment of chronic-phase CML with imatinib as initial therapy was found to induce durable responses in a high proportion of patients. (ClinicalTrials.gov number, NCT00006343 [ClinicalTrials.gov].)

Antineoplastic Agents↗
PubMed2006

Dasatinib induces notable hematologic and cytogenetic responses in chronic-phase chronic myeloid leukemia after failure of imatinib therapy.

Although imatinib induces marked responses in patients with chronic myeloid leukemia (CML), resistance is increasingly problematic, and treatment options for imatinib-resistant or -intolerant CML are limited. Dasatinib, a novel, highly potent, oral, multitargeted kinase inhibitor of BCR-ABL and SRC family kinases, induced cytogenetic responses in a phase 1 study in imatinib-resistant or -intolerant CML and was well tolerated. Initial results are presented from a phase 2 study of 186 patients with imatinib-resistant or -intolerant chronic-phase CML (CML-CP) designed to further establish the efficacy and safety of dasatinib (70 mg twice daily). At 8-months' follow-up, dasatinib induced notable responses, with 90% and 52% of patients achieving complete hematologic and major cytogenetic responses (MCyR), respectively. Responses were long lasting: only 2% of patients achieving MCyR progressed or died. Importantly, comparable responses were achieved by patients carrying BCR-ABL mutations conferring imatinib resistance. Dasatinib also induced molecular responses, reducing BCR-ABL/ABL transcript ratios from 66% at baseline to 2.6% at 9 months. Nonhematologic adverse events were generally mild to moderate, and most cytopenias were effectively managed with dose modifications. Cross-intolerance with imatinib was not evident. To conclude, dasatinib induces notable responses in imatinib-resistant or -intolerant CML-CP, is well tolerated, and represents a promising therapeutic option for these patients. This trial was registered at www.clinicaltrials.gov as CA180013.

Adult↗
PubMed2006

The extracellular nucleotide UTP is a potent inducer of hematopoietic stem cell migration.

Homing and engraftment of hematopoietic stem cells (HSCs) to the bone marrow (BM) involve a complex interplay between chemokines, cytokines, and nonpeptide molecules. Extracellular nucleotides and their cognate P2 receptors are emerging as key factors of inflammation and related chemotactic responses. In this study, we investigated the activity of extracellular adenosine triphosphate (ATP) and uridine triphosphate (UTP) on CXCL12-stimulated CD34+ HSC chemotaxis. In vitro, UTP significantly improved HSC migration, inhibited cell membrane CXCR4 down-regulation by migrating CD34+ cells, and increased cell adhesion to fibronectin. In vivo, preincubation with UTP significantly enhanced the BM homing efficiency of human CD34+ cells in immunodeficient mice. Pertussis toxin blocked CXCL12- and UTP-dependent chemotactic responses, suggesting that G-protein alpha-subunits (Galphai) may provide a converging signal for CXCR4- and P2Y-activated transduction pathways. In addition, gene expression profiling of UTP- and CXCL12-treated CD34+ cells and in vitro inhibition assays demonstrated that Rho guanosine 5'-triphosphatase (GTPase) Rac2 and downstream effectors Rho GTPase-activated kinases 1 and 2 (ROCK1/2) are involved in UTP-promoted/CXCL12-dependent HSC migration. Our data suggest that UTP may physiologically modulate the homing of HSCs to the BM, in concert with CXCL12, via the activation of converging signaling pathways between CXCR4 and P2Y receptors, involving Galphai proteins and RhoGTPases.

Adenosine Triphosphate↗
PubMed2006

Mobilization of bone marrow-derived hematopoietic and endothelial stem cells after orthotopic liver transplantation and liver resection.

In animals, the bone marrow (BM) is a source of liver-repopulating cells with therapeutic potential in case of tissue damage. However, the early response of human BM-derived stem cells (SC) to liver injury is still unknown. Here, we studied 24 patients undergoing orthotopic liver transplantation (OLT) for end-stage liver disease or hepatocellularcarcinoma, and 13 patients submitted to liver resection. The concentration of circulating BM-derived SC was determined by phenotypic analysis and clonogenic assays. Moreover, we assessed the serum level of inflammatory and tissue-specific cytokines. Reverse transcriptase-polymerase chain reaction and fluorescence-in situ hybridization were also used to characterize mobilized SC. At baseline, patients showed a significant lower concentration of circulating CD133(+), CD34(+) SC and clonogenic progenitors (colony-forming unit cells) than healthy controls. However, the time-course evaluation of peripheral blood cells after OLT demonstrated the significant early mobilization of multiple subsets of hematopoietic and endothelial stem/progenitor cells. Cytogenetic and molecular analyses of CD34(+) cells showed the host origin of mobilized SC and the expression of transcripts for GATA-4, cytokeratin 19, and alpha-fetoprotein hepatocyte markers. In contrast with OLT, only total circulating CD34(+) cells significantly increased after liver resection. Mobilization of BM cells after OLT or liver surgery was associated with increased serum levels of granulocyte-colony stimulating factor, interleukin-6, stem cell factor, hepatocyte growth factor, and vascular endothelial growth factor. In summary, we demonstrate that tissue damage after OLT and liver resection induces increased serum levels of multiple cytokines but only ischemia/reperfusion injury associated with OLT results in the remarkable mobilization of BM stem/progenitor cells.

Adult↗
PubMed2006

Efficacy of liposomal daunorubicin and cytarabine as reinduction chemotherapy in relapsed acute lymphoblastic leukaemia despite expression of multidrug resistance-related proteins.

The treatment of relapsed adult acute lymphoblastic leukaemia (ALL) is frequently unsuccessful with current chemotherapy regimens, and often there is an overexpression of multidrug resistance (MDR)-related proteins. Liposomal encapsulation makes daunorubicin (DNR) less sensitive to the efflux effect of P-glycoprotein (PGP), and in vitro data indicate that liposomal-encapsulated DNR (Daunoxome-DNX) is more toxic than DNR against ALL cell lines. In this study, we assessed the in vivo and in vitro efficacy and toxicity of DNX plus cytarabine (Ara-C) as reinduction chemotherapy in 25 relapsed ALL patients (pts). The expression of MDR-related proteins (PGP, MRP1 and LRP) was also analysed. Of the 25 pts, 12 were males and 13 females; median age was 32 yr (range 18-58). Six cases were ALL T and 19 ALL B; eight pts were Ph+ (32%), and nine Bcr-Abl+ (36%). The expression of MDR-related proteins, and DNR and DNX retention and induction of apoptosis in leukaemic cells were evaluated in all cases. Seventeen of 25 (68%) pts were at first relapse and eight (32%) at second or subsequent relapse. The DNX was given in a dose of 80 mg/m(2)/d (days 1-3) in 11/25 pts (44%) and in a dose of 100 mg/m(2)/d (days 1-3) in 14/25 pts (66%). In all pts, Ara-C was administered in a dose of 2 g/m(2) (days 1-5). Twenty pts (80%) achieved a complete remission (CR) and two (8%) entered a partial remission (PR) for an overall response (OR) rate of 88% (22/25), with a tolerable toxicity and without significant cardiotoxicity. Before the start of DNX therapy, 18/25 (72%) cases overexpressed at least one MDR-related protein compared with 9/25 (36%) cases with MDR overexpression at diagnosis (P = 0.01). Taking into account the small number of cases, the response rate was not affected by MDR expression and the in vitro results also showed a higher uptake and apoptotic cell death by DNX compared with DNR. Twelve pts subsequently underwent allogeneic bone marrow transplantation (11 unrelated donor BMT, and one sibling BMT). The overall survival was 39% after 12 months. These data show the efficacy (OR rate 88% and CR rate 80%) of DNX plus Ara-C as reinduction therapy in very poor-risk ALL pts and the response rate seems not to be affected by MDR overexpression. Moreover, the high rate of remissions and the good clinical tolerance in heavily pretreated pts suggest a promising role of DNX in ALL chemotherapy regimens.

Adolescent↗
PubMed2006

Resolution of a Pseudomonas aeruginosa outbreak in a hematology unit with the use of disposable sterile water filters.

We observed a significant increase of Pseudomonas aeruginosa bacteremias during 2002. Eighty-five microbiological samples were taken from different potential sources of infection. Twenty-nine out of 46 specimens obtained from water taps, shower heads and siphons tested positive for Pseudomonas aeruginosa. Weekly pharyngeal and rectal swabs in high risk patients, use of tap water after running the tap for at least 5 minutes and use of weekly disposable sterile filters in all taps and showers resulted in a significant decrease in Pseudomonas aeruginosa bacteremias. Moreover, we observed a significant reduction in Pseudomonas aeruginosa-positive surveillance cultures after implementation of these measures.

Cross Infection↗
PubMed2006

Evolving concepts in the management of chronic myeloid leukemia: recommendations from an expert panel on behalf of the European LeukemiaNet.

The introduction of imatinib mesylate (IM) has revolutionized the treatment of chronic myeloid leukemia (CML). Although experience is too limited to permit evidence-based evaluation of survival, the available data fully justify critical reassessment of CML management. The panel therefore reviewed treatment of CML since 1998. It confirmed the value of IM (400 mg/day) and of conventional allogeneic hematopoietic stem cell transplantation (alloHSCT). It recommended that the preferred initial treatment for most patients newly diagnosed in chronic phase should now be 400 mg IM daily. A dose increase of IM, alloHSCT, or investigational treatments were recommended in case of failure, and could be considered in case of suboptimal response. Failure was defined at 3 months (no hematologic response [HR]), 6 months (incomplete HR or no cytogenetic response [CgR]), 12 months (less than partial CgR [Philadelphia chromosome-positive (Ph(+)) > 35%]), 18 months (less than complete CgR), and in case of HR or CgR loss, or appearance of highly IM-resistant BCR-ABL mutations. Suboptimal response was defined at 3 months (incomplete HR), 6 months (less than partial CgR), 12 months (less than complete CgR), 18 months (less than major molecular response [MMolR]), and, in case of MMolR loss, other mutations or other chromosomal abnormalities. The importance of regular monitoring at experienced centers was highlighted.

Antineoplastic Agents↗
PubMed2006

Achieving a major molecular response at the time of a complete cytogenetic response (CCgR) predicts a better duration of CCgR in imatinib-treated chronic myeloid leukemia patients.

PURPOSE: Most patients with chronic-phase chronic myeloid leukemia (CML) who receive imatinib achieve a complete cytogenetic remission (CCgR) and low levels of BCR-ABL transcripts. CCgR is durable in the majority of patients but relapse occurs in a subset. EXPERIMENTAL DESIGN: To determine the potential of quantitative reverse transcription-PCR of BCR-ABL to predict cytogenetic relapse, we serially monitored residual disease in 97 CML patients with an imatinib-induced CCgR. Patients with late chronic phase CML after IFN-alpha failure were treated with imatinib (400 mg daily). RESULTS: During the imatinib median follow-up time of 36 months (range, 12-54 months), disease monitoring occurred by cytogenetics and quantitative PCR. Twenty percent of patients experienced cytogenetic relapse at a median of 18 months after CCgR and a median of 24 months after starting imatinib. None of the possible prognostic factors studied in univariate and multivariate analyses seemed to predict for loss of cytogenetic response but the reduction of BCR-ABL transcript levels at the time of CCgR is an important prognostic factor. CONCLUSIONS: In our study, we showed not only that achieving a major molecular remission at 12 months is predictive of a durable cytogenetic remission but also that patients who achieved a major molecular remission (expressed both as the BCR-ABL/beta2 microglobulin ratio % <0.0005 and as a 3-log reduction from median baseline value) already at the time of first achieving a CCgR have significantly longer cytogenetic remission durations than those without this magnitude of molecular response (P < 0.05).

Adult↗