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Giuseppe Leone

Publications and source records attributed to Giuseppe Leone.

86 records · Page 5Linked to original sources
PubMed2002

Kinetics of hemopoietic recovery after peripheral blood stem cell transplantation: impact of stem cell purification and G-CSF.

We investigated the role of stem cell purification and G-CSF (early vs. delayed vs. no G-CSF) administration on hemopoietic recovery and supportive care requirements after stem cell transplantation. Thirty-two patients submitted to autologous CD34(+) peripheral blood stem cell transplantation (PBSCT) were studied, and data were compared to patients undergoing unfractionated peripheral blood stem cell transplantation (uPBSCT) matched for age, disease, and conditioning regimen. Except for PMN, hemopoietic recovery was significantly slower and supportive care requirements were significantly higher after CD34(+) PBSCT. Median time to PMN >0.5 x 10(9)/l was 13 days (range 9-27) and 13 d (range 9-23); reticulocytes (Ret) >1% was 14.5 d (range 12-34) and 12 d (range 10-27); high-fluorescence reticulocytes (HFR) >5% was 12 d (range 9-26) and 9 d (range 7-11); platelets >50 x 10(9)/l and >100 x 10(9)/l was 20 d (range 10-240), 12 d (range 9-60) and 33 d (range 15-720), 15 d (range 11-210). When the analysis was performed on subgroups of patients (early/delayed/no G-CSF), early G-CSF significantly promoted PMN recovery (>0.5 x 10(9)/l and >1.0 x 10(9)/l) compared to no G-CSF, without affecting RBCs or platelet recovery. Delayed G-CSF did not improve PMN recovery compared to patients not receiving G-CSF, did not result in a significant reduction of drug requirements, and had a negative impact on erythroid and platelet recovery. In conclusion, these preliminary data suggest that G-CSF is useful if given early after CD34(+) PBSCT. CD34(+) PBSCT may overall require a significant increase of resource utilization that should be outweighed by proven clinical benefit.

Adolescent↗
PubMed2002

Highly active antiretroviral therapy and allogeneic CD34(+) peripheral blood progenitor cells transplantation in an HIV/HCV coinfected patient with acute myeloid leukemia.

OBJECTIVE: To evaluate the safety, feasibility, and efficacy of allogeneic stem cell transplantation (SCT) for acute myelogenous leukemia (AML) in a young female coinfected by HIV and HCV undergoing highly active antiretroviral therapy (HAART). PATIENTS AND METHODS: A 33-year-old female HIV(+), HCV(+) in complete remission after standard chemotherapy was submitted to CD34(+) selected allogeneic transplantation from her HLA-identical HIV(-) brother after myeloablative regimen. HAART was started before transplantation, achieving a reduction of HIV load to undetectable levels. GVHD prophylaxis was carried out with cyclosporine A alone. RESULTS: The patient achieved prompt and durable engraftment with acute GVHD grade II easily managed with steroids; CMV prophylaxis was prolonged, no clinically relevant infectious complications developed early after transplantation and during follow-up. HIV viremia was controlled by HAART although medication adherence was reduced early after transplantation and required drug adjustment. There was a gradual recovery of immune cells with normal CD4-cell count 39 months after engraftment, a significantly higher level than before transplantation. At 39 months post-transplantation follow-up the patient is alive and in continuous complete remission with undetectable levels of plasma HIV RNA on HAART. CONCLUSION: The introduction of HAART has recently changed the paradigm of AIDS, allowing the control of HIV replication, the reduction of opportunistic infections, and the overall improvement of survival. One may therefore reconsider the current exclusion of patients with AIDS and a concomitant lethal malignancy from programs of high-dose chemotherapy and stem cell transplantation, as suggested by this report.

Adult↗
PubMed2002

Transforming growth factor-beta1 causes transcriptional activation of CD34 and preserves haematopoietic stem/progenitor cell activity.

Stem/progenitor cells endowed with in vitro and in vivo haematopoietic activity express the surface protein CD34. Transforming growth factor beta1 (TGF-beta1) is one of the soluble molecules that regulate cell cycle and differentiation of haematopoietic cells, but has pleiotropic activities depending on the state of responsiveness of the target cells. It has previously been shown that TGF-beta1 maintains human CD34+ haematopoietic progenitors in an undifferentiated state, independently of any cell cycle effect. Here, we have shown that TGF-beta1 upregulates the human CD34, an effect that was evident in primary stem/progenitor cells (CD34+lin-) both at the transcriptional and protein levels, and was not associated with any relevant effect on cell growth. The presence of TGF-beta1 influenced differentiation, maintaining primary CD34+/Lin- in an undifferentiated state. This effect was associated with Smad activation and with a dramatic decrease in p38 phosphorylation. Moreover, blocking p38 phosphorylation by the SB202190 inhibitor increased CD34 RNA levels but did not enhance CD34 protein expression in CD34+/Lin- cells, suggesting that modulation of multiple signalling pathways is necessary to reproduce TGF-beta1 effects. These data establish the role that TGF-beta1 has in the modulation of the CD34 stem/progenitor protein and stem/progenitor functions, providing important clues for understanding haematopoietic development and a potential tool for the modulation of human haematopoiesis.

Antigens, CD34↗
PubMed2002

Survival and cell cycle control in early hematopoiesis: role of bcl-2, and the cyclin dependent kinase inhibitors P27 and P21.

Homeostasis of the hematopoietic system is maintained by proliferation and differentiation of a small number of long-term surviving, self-renewing stem cells, which give rise to the fully mature elements. The fine interplay between differentiation, proliferation and death by apoptosis determines the equilibrium of this system. Thus, genes involved in the control of these processes are very important in the regulation and development of hematopoietic cells especially in the initial stages. The interactions among cyclins, their specific cyclin-dependent kinases (CDKs) and, a number of cyclin-dependent kinase inhibitors (CDKIs) such as p27 and p21, exert a direct control on the cell cycle but can also produce other independent effects on hematopoietic differentiation. Proteins of the Bcl-2 family are also crucial in regulating the balance between entry into apoptosis and survival capacity and their roles change in the course of differentiation. In addition, a number of autocrine and paracrine soluble factors (such as TGF-beta1) modulate the behavior and differentiation potential of hematopoietic elements. Studies on a few in vitro systems of early hematopoietic differentiation have stressed the importance of Bcl-2 and of the CDKIs p27 and p21 at this stage, have confirmed cell-cycle independent effects and have demonstrated how the modulation and the effects in response to different stimuli is mostly dependent on the differentiation stage of the target cells.

Cell Cycle↗
PubMed2002

Periodic morphologic, cytogenetic and clonality evaluation after autologous peripheral blood progenitor cell transplantation in patients with lymphoproliferative malignancies.

BACKGROUND AND OBJECTIVES: Myelodysplastic syndrome (MDS), secondary acute myeloid leukemia (sAML) and clonal karyotypic abnormalities, have been recognized as relatively frequent and potentially serious complications of autologous peripheral blood progenitor cell transplantation (PBPCT) for Hodgkin's disease (HD), non-Hodgkin's lymphoma (NHL) or multiple myeloma (MM). DESIGN AND METHODS: We analyzed 66 patients, undergoing PBPCT for HD, NHL, MM or chronic lymphocytic leukemia (CLL). Patients reported in this study had to be in continuous complete remission after transplantation without receiving chemo-radiotherapy or other biological response modifiers, had to show absence of cytogenetic abnormalities and myelodysplastic features at transplantation and had to have at least 12 months of follow-up. We evaluated the bone marrow, peripheral blood, cytogenetics and clonality (HUMARA) 12 months after the transplant and thereafter every 12 months or every 6 months if lineage dysplasia, clonal or cytogenetic abnormalities were detected. RESULTS: We did not observe MDS/sAML, according to the FAB classification, in 163 assessments of 66 patients over a median follow-up of 25 months (range 12-106) after PBPCT. Twelve patients showed lineage dysplasia: six patients had dyserythropoiesis, 2 patients dysgranulopoiesis, one dysmegakaryocytopoiesis, two patients showed double lineage dysplasia (erythroid and granulocytic), and one patient showed dysgranulopoiesis at the first control acquiring dyserythropoiesis at the next follow-up. We found three cytogenetic abnormalities in the absence of concomitant dysplastic features: transient -5q, -Y, fra(10)(q25). The female patient with the cytogenetic abnormality -5q showed transient unbalanced clonality by HUMARA assay; further controls documented normalization of both clonality and cytogenetics. INTERPRETATION AND CONCLUSIONS: The occurrence of MDS/sAML depends on a variety of risk factors such as the number and type of prior courses of chemo-radiotherapy, total body irradiation in conditioning regimen, cytogenetic and morphologic alterations prior to transplant. This may account for the difference in reporting MDS/sAML after transplantation. The lack of exposure to recognized risk factors for MDS/sAML in our patients may account for the absence of this complication in this study. We consider that the use of stringent morphologic criteria, especially during the first period after PBPCT, combined with cytogenetic, clonality and FISH analyses are necessary for a correct diagnosis of MDS and to overcome the limitations of the FAB and WHO classifications in this setting.

Adult↗
PubMed2002

Chronic disseminated candidiasis in patients with hematologic malignancies. Clinical features and outcome of 29 episodes.

BACKGROUND AND OBJECTIVES: To evaluate the characteristics of patients affected by hematologic malignancies who developed a chronic disseminated candidiasis (CDC), and to ascertain the factors that influenced the outcome, in a retrospective study conducted between January 1990 and December 2000, in 4 Hematology Divisions. DESIGN AND METHODS: CDC was diagnosed by clinical features combined with radiological and/or histologic and/or microbiological data. RESULTS: Twenty-eight patients (male/female 14/14; average age 42 years, range 12-67) developed a CDC. Twenty had acute myeloid leukemia, 5 had acute lymphocytic leukemia and 3 had non-Hodgkin's lymphoma. All patients received chemotherapy, including cytarabine for 21 of them (75%). Before the infection, 22 patients (79%) were neutropenic (absolute neutrophil count < 0.5 x 10(9)/L) for an average of 20 days (8-36), but at CDC diagnosis only 3 patients (11%) were neutropenic. Twenty-two patients (75%) received antifungal prophylaxis for an average of 15 days (10-60). Before diagnosis of CDC, 9 patients (32%) had a candidemia. The sites compromised by CDC were: liver in 27 patients (96%) and/or spleen in 11 patients (38%). Ten patients had other organs involved: lung in 6 patients (21%), kidney in 4 patients (14%), other sites 2 patients (7%). Abdominal ultrasonography was positive in 96% of patients (27/28), and abdominal computed tomography-scan was positive in 100% of cases in which it was performed (21/21). Liver biopsy was positive in 10/15 patients (67%). The main signs and symptoms were: fever 86%, abdominal pain 54%, diarrhea 32%, tenderness 25%, vomiting 25%, jaundice 29%, dysphagia 7%. Among chemical analyses, the most sensitive test was alkaline phosphatase, with a 3-5-fold increase in 24 patients (86%); an increase of liver transaminases and g-glutamyl transferase was observed in less than 50% of patients. By 30 days after diagnosis 4 patients had died, 1 from infection, and 3 progression of the hematologic malignancy without signs of active CDC. Within 3 months from diagnosis 14 out of the remaining 24 patients (58%) received further chemotherapy: in particular, 2 patients underwent transplantation procedures. INTERPRETATION AND CONCLUSIONS: In our experience CDC is not a fatal complication of patients with hematologic malignancy, on the contrary to that observed for other fungal infections (i.e. aspergillosis, candidemia), characterized by a higher mortality rate. The major problem of this fungal complication is correlated to the delay in the following treatment for the hematologic malignancy with a high risk of progression of malignancy.

Adolescent↗
PubMed2002

Rituximab reduces the number of peripheral blood B-cells in vitro mainly by effector cell-mediated mechanisms.

BACKGROUND AND OBJECTIVES: The humanized CD20 mono- clonal antibody, rituximab, has significant anti-tumor activity in patients with B-cell non-Hodgkin's lymphoma and induces depletion of B-cells in vivo. It was the objective of this study to define the contribution of the different mechanisms of action of rituximab on primary normal and malignant B-cells. DESIGN AND METHODS: Primary human B-lymphocytes and effector cell fractions were isolated from peripheral blood of normal donors using an immunomagnetic separation technique. Blood samples from 20 patients with chronic lymphocytic leukemia (CLL) were studied and the B-lymphoblastoid Daudi cell line was used as a control. B-cells were cultured in the presence or absence of rituximab adding a secondary hyper-crosslinking antibody, serum as source of complement or different effector cell fractions. The cells were analyzed by immunofluorescence staining and flow cytometry. RESULTS: In contrast to the B-lymphoblastoid Daudi cell line, the number of highly purified normal peripheral blood CD19+ cells was only minimally affected by rituximab in the presence of autologous serum. A significant reduction in the number of B-cells was observed when mononuclear cells from peripheral blood were added back. To identify the cell type which mediates this effect, CD3+ T-cells, CD56+ cells, and CD14+ monocytes were added to selected CD22+ B-cells. A marked B-cell decrease was only observed in the presence of CD56+ and CD14+ cells in an effector to target ratio of 10:1. The experiments with mononuclear cells from patients with CLL showed a B-cell reduction by rituximab, which was significantly enhanced following addition of granulocyte-macrophage colony-stimulating factor (GM-CSF). INTERPRETATION AND CONCLUSIONS: These data support the important role of cell-mediated mechanisms in the B-cell-depleting action of rituximab and suggest that pre-treatment with GM-CSF could improve the response to rituximab in patients with CLL.

Antibodies, Monoclonal↗
PubMed2002

Screening for inherited thrombophilia: indications and therapeutic implications.

BACKGROUND AND OBJECTIVES: In recent years knowledge concerning inherited and acquired causes of thrombophilia has increased greatly. The most common inherited traits (deficiency in antithrombin, protein C, or protein S, factor V Leiden, prothrombin G20210A) and mild hyperhomocysteinemia are diagnosed in at least 40% of patients with venous thromboembolism (VTE). INFORMATION SOURCES: The authors work in this field, contributing to multicenter clinical and laboratory investigations and to peer-reviewed journals with original papers. The material examined in this review includes articles published in journals covered by MedLine. STATE OF THE ART: The associated risk for VTE is different according to genotype, being higher among the carriers of natural anticoagulant deficiencies and homozygotes for factor V Leiden. The overall prevalence of thrombophilic traits in the general population being near to 10% renders the probability of carrying multiple defects not excessively rare, with a further increase in thrombotic risk of up to 20-fold. Thus, clinical penetrance is heterogeneous, producing either mild or severe venous thrombotic manifestations, which can be unprovoked or associated with circumstantial risk factors and occur in either young or advanced age. More recently, inherited thrombophilia has been focused on as an important determinant of complications of pregnancy and puerperium. As expected, inherited thrombophilia produces an increased risk of VTE, particularly during puerperium. Moreover it is well established that thrombophilic women have an increased risk of late and/or recurrent fetal loss; whether they are at higher risk of pre-eclampsia, fetal growth restriction, and abruptio placentae is debated. Overall, 40% of women with obstetric complications other than VTE carry a thrombophilic trait. Yet, as a rule VTE and obstetric complications seem to occur in different individuals, probably because of the presence of unknown factors favoring one or other of these clinical manifestations. CONCLUSIONS AND PERSPECTIVES: Inherited thrombophilia is now viewed as a multicausal model, the clinical event being the result of gene-gene and gene-environment age-dependent interactions; the associated clinical manifestations can be heterogenous as regards severity as well as type of event (VTE or obstetric complication). Therefore the criteria for screening affected individuals who have suffered from the above complications or their relatives should not be very stringent. The patient's genotype could be a main determinant of the features of primary or secondary prophylaxis used in the affected individual.

Antithrombins↗
PubMed2002

DNA methylation and demethylating drugs in myelodysplastic syndromes and secondary leukemias.

BACKGROUND AND OBJECTIVES: Methylation of DNA is a common epigenetic modification that plays an important role in the control of gene expression in mammalian cells. This process involves CpG dinucleotide sequences and is catalyzed by DNA-methyltransferase enzymes. Under physiological conditions, methylated CpG sites are only present in DNA sequences typical of bulk chromatin, where the DNA is inaccessible to transcription factors. In contrast, CpG islands of promoter regions are usually unmethylated (with few exceptions such as the genes on the inactive X-chromosome). DNA methylation abnormalities have recently emerged as the most frequent molecular changes in hematopoietic neoplasms. INFORMATION SOURCES: The authors of the present review are currently working in the field of myelodysplastic syndromes and secondary leukemias and have contributed original papers to peer-reviewed journals. The material analyzed in the present review includes articles and reviews published in journals covered by the Science Citation Index, and abstracts presented at recent international oncology and hematology meetings. STATE OF THE ART: Methylation and transcriptional status are inversely correlated, the hypermethylation of genes involved in cell-cycle control and apoptosis could have a pathogenetic role in the development of cancer. In particular, high-risk myelodysplastic syndromes (MDS) and secondary leukemias (SL) show a high prevalence of tumor-suppressor gene hypermethylation. The use of irreversible DNA methyltransferase inhibitors, such as 5-azacytidine and decitabine, appears to be a promising therapeutic option for the treatment of MDS and SL. Large clinical trials are still ongoing, but preliminary data recently published indicate for the first time that the natural history of MDS may be changed by a non-intensive treatment. CONCLUSIONS AND PERSPECTIVES: Treatment with demethylating agents, 5-azacytidine and decitabine, at present results in significantly higher response rates, improved quality of life, reduced risk of leukemic transformation, and improved survival, when compared to supportive care. Azacytidine and decitabine provide a new treatment option, and should be the treatment choice for elderly patients with high risk MDS. It is whorty in fact that azacytidine and decitabine are especially active in patients with poor prognosis MDS. The combination with histone deacetylase inhibitors may increase the efficacy of hypomethylating agents in vivo.

Antimetabolites, Antineoplastic↗
PubMedDate not supplied

The intracoelomic route: a new approach for in utero human cord blood stem cell transplantation.

The intracoelomic route for in utero hematopoietic stem cell transplantation has been evaluated in pre-immune fetal sheep and the engraftment characteristics defined. Twelve ovine fetuses (gestational ages: 40-45 days) received intracoelomic transplants of human CD3-depleted (50 x 10(6) per lamb) or CD34-selected (1-2 x 10(5) per lamb) cord blood hematopoietic stem cells. Engraftment was evaluated from cell suspension of the liver, spleen, bone marrow and thymus by flow cytometry, cloning assays and polymerase chain reaction (PCR) analysis for human beta(2)-microglobulin gene. The engraftment of liver samples was also evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR), fluorescent in situ hybridization (FISH) and immunohistochemistry. Four fetuses (33%) aborted shortly after intracoelomic transplantation and were not evaluable for engraftment. Engraftment was detected in 4 fetuses obtained from cesarean delivery on day 70 after transplantation of CD3-depleted cord blood cells. The degree of engraftment in these 4 fetuses ranged from 6 to 22% in the different organs (as revealed by antigenic analysis of human CD45 with flow cytometry). Three fetuses obtained after cesarean section at 102 (No. 435184) and 105 (Nos 915293, 037568) days and 1 fetus delivered at term, which received CD34-selected cord blood cells, had human engraftment with 10, 32, 20 and 10% CD45+ cells in bone marrow, respectively. A further check of human chimerism was done at 1 year after birth of the fetus delivered at term and 7.6% of bone marrow chimerism was detected. In 6 out of 8 fetuses evaluable for human engraftment, chimerism was confirmed by PCR analysis for human beta(2)-microglobulin which also identified human cells in brain, spinal cord, heart, lung and skeletal muscle. On liver samples, FISH and RT-PCR confirmed the xenograft of human cells and the immunohistochemical analysis detected human markers of hematopoietic and hepatic lineage of differentiation. This preliminary study indicates that intracoelomic transplantation of human hematopoietic stem cells in fetal lambs is feasible and effective in terms of hematopoietic engraftment.

Animals↗
PubMedDate not supplied

Thrombopoietin serum levels in patients with inflammatory bowel disease with and without previous thromboembolic events.

BACKGROUND/AIMS: Patients affected by inflammatory bowel disease frequently suffer from thromboembolic complications and mesenteric microvascular occlusion could be involved in the pathogenesis of inflammatory bowel disease. Increased platelet counts and abnormal platelet function seem to play a crucial role in determining the hypercoagulable state observed in inflammatory bowel disease. Thrombopoietin is considered the primary regulator of thrombopoiesis and recent studies have investigated the role of thrombopoietin in inflammatory bowel disease. However, the available data are not conclusive. The aim of this study was to assess thrombopoietin serum levels in inflammatory bowel disease patients according to platelet counts, disease activity and previous thrombotic events. METHODOLOGY: Seventy-one patients with inflammatory bowel disease [41 with ulcerative colitis and 30 with Crohn's disease] and 30 healthy controls were investigated. Eight (11%) inflammatory bowel disease patients had suffered previous thromboembolic complications, none had active thrombosis. Thrombopoietin serum levels were measured by ELISA. RESULTS: Mean thrombopoietin levels were significantly increased in inflammatory bowel disease patients with active disease compared to both healthy controls and patients with inactive disease. Platelet counts were significantly higher only in patients with active disease with respect to healthy subjects. No correlation was found between thrombopoietin levels and platelet counts in either controls or inflammatory bowel disease patients. No differences were found either in thrombopoietin levels or in platelet counts comparing inflammatory bowel disease patients with and without thromboembolic complications. CONCLUSIONS: Our data show elevated thrombopoietin levels in active inflammatory bowel disease. However, no correlation was found between platelet counts and thrombopoietin levels, supporting the hypothesis that other circulating factors than thrombopoietin interact in determining reactive thrombocytosis. Furthermore, thrombopoietin levels did not differ in inflammatory bowel disease patients with or without previous thromboembolic events. This finding could be probably explained by the lack of patients with active thrombosis at the moment of inclusion in the study.

Adult↗