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Giuseppe Basso

Publications and source records attributed to Giuseppe Basso.

At least 37 records · Page 2Linked to original sources
PubMed2005

A leukemia-enriched cDNA microarray platform identifies new transcripts with relevance to the biology of pediatric acute lymphoblastic leukemia.

BACKGROUND AND OBJECTIVES: Microarray gene expression profiling has been widely applied to characterize hematologic malignancies, has attributed a molecular signature to leukemia subclasses and has allowed new subclasses to be distinguished. We set out to use microarray technology to identify novel genes relevant for leukemogenesis. To this end we used a unique leukemia-enriched cDNA microarray platform. DESIGN AND METHODS: The systematic sequencing of cDNA libraries of normal and leukemic bone marrow allowed us to increase the number of genes to yield a new release of a previously generated cDNA microarray. Using this platform we analyzed the expression profiles of 4,670 genes in bone marrow samples from 18 pediatric patients with acute lymphoblastic leukemia (ALL). RESULTS: Expression profiling consistently distinguished the leukemia patients into three groups, those with T-ALL, B-ALL and B-ALL with MLL/AF4 rearrangement, in agreement with the clinical classification. Our platform identified 30 genes that best discriminate these three subtypes. Using mini-array technology these 30 genes were validated in another cohort of 17 patients. In particular we identified two novel genes not previously reported: endomucin (EMCN) and ubiquitin specific protease 33 (USP33) that appear to be over-expressed in B-ALL relative to their expression in T-ALL. INTERPRETATION AND CONCLUSIONS: Microarray technology not only allows the distinction between disease subclasses but also offers a chance to identify new genes involved in leukemogenesis. Our approach of using a unique platform has proven to be fruitful in identifying new genes and we suggest exploration of other malignancies using this approach.

Adolescent↗
PubMed2005

Treatment reduction in highly selected standard-risk childhood acute lymphoblastic leukemia. The AIEOP ALL-9501 study.

BACKGROUND AND OBJECTIVES: Treatment of childhood standard-risk (SR) acute lymphoblastic leukemia (ALL) is generally successful. However, intensive chemotherapy regimens may be associated with severe treatment sequelae. Efforts are therefore being made to identify those patients in whom less intensive treatment would be equally successful but cause fewer long-term sequelae. The aim of this study was to evaluate the efficacy of treatment reduction in a subset of children with ALL at minimal risk of failure. DESIGN AND METHODS: The population of patients with SR ALL included children aged between 1 and 6 years with less than 20,000 WBC/mm3, non-T immunophenotype, DNA index between 1.16 and 1.6, absence of t(9;22) and t(4;11) clonal translocations, no extramedullary leukemia, good response to prednisone and complete remission (CR) at the end of induction therapy. A reduced-intensity, BFM-type treatment schedule (AIEOP-ALL 9501 protocol) was used. Induction therapy was based on vincristine, prednisone, L-asparaginase and intrathecal methotrexate only; high-dose-methotrexate (2 g/m2) was given x4. The BFM Protocol II was given as reinduction therapy; thus the total dose of anthracyclines was 120 mg/m2 and no epipodophyllotoxins or cranial irradiation were employed. RESULTS: Between May 1995 and December 1999, 123 patients were identified as having SR-ALL (7.8% of the ALL-95 population), of whom 102 received the SR protocol. After a median follow-up of 5.9 years, 11 patients in the SR protocol had relapsed, 1 had died in remission, and 1 had developed a second malignant neoplasm. The probabilities (standard errors) of survival and event-free survival (EFS) were, respectively, 97.0% (1.7) and 86.7% (3.5) at 5 years, and 95.3% (2.4) and 86.7% (3.5) at 7 years. INTERPRETATION AND CONCLUSIONS: Although most of the relapsed patients were rescued, the long-term EFS probability in this small, highly selected group of patients remains inferior to expectation. Thus, alternative selection criteria, such as treatment response measured by minimal residual disease, should be considered to address the issue of treatment reduction.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2004

Therapeutic effectiveness of recombinant cancer vaccines is associated with a prevalent T-cell receptor alpha usage by melanoma-specific CD8+ T lymphocytes.

Definition of immune variables that correlate with the antitumor activity of cancer vaccines is critical for monitoring immunotherapy protocols. To define surrogate end points predictive of the therapeutic efficacy of recombinant vaccines based on melanoma antigen tyrosinase-related protein (TRP)-2, we evaluated several properties of antigen-specific CD8(+) T lymphocytes in single mice undergoing either prophylactic or therapeutic immunization. Predictive markers for the efficacy of genetic vaccination were identified in the prophylactic model used. Interestingly, the number of tetramer(+) CD8(+) T lymphocytes expanded in vitro after a single cycle of stimulation with the immunodominant TRP-2 peptide was of the highest predictive value. In the therapeutic model, no variable examined at a single mouse level predicted the long-term therapeutic effect. Mice that survived did not show the highest expansion of antigen-specific lymphocytes or the more functionally active effectors, ex vivo or after in vitro culture with the peptide antigen. Successful therapy correlated strictly with the skewing of the T-cell receptor repertoire of tetramer-sorted, TRP-2-specific CD8(+) T lymphocytes, which showed a preferential alpha chain usage with a common CDR3 region.

Adenoviridae↗
PubMed2004

Genetic evidence for lineage-related and differentiation stage-related contribution of somatic PTPN11 mutations to leukemogenesis in childhood acute leukemia.

SHP-2 is a protein tyrosine phosphatase functioning as signal transducer downstream to growth factor and cytokine receptors. SHP-2 is required during development, and germline mutations in PTPN11, the gene encoding SHP-2, cause Noonan syndrome. SHP-2 plays a crucial role in hematopoietic cell development. We recently demonstrated that somatic PTPN11 mutations are the most frequent lesion in juvenile myelomonocytic leukemia and are observed in a smaller percentage of children with other myeloid malignancies. Here, we report that PTPN11 lesions occur in childhood acute lymphoblastic leukemia (ALL). Mutations were observed in 23 of 317 B-cell precursor ALL cases, but not among 44 children with T-lineage ALL. In the former, lesions prevalently occurred in TEL-AML1(-) cases with CD19(+)/CD10(+)/cyIgM(-) immunophenotype. PTPN11, NRAS, and KRAS2 mutations were largely mutually exclusive and accounted for one third of common ALL cases. We also show that, among 69 children with acute myeloid leukemia, PTPN11 mutations occurred in 4 of 12 cases with acute monocytic leukemia (FAB-M5). Leukemia-associated PTPN11 mutations were missense and were predicted to result in SHP-2 gain-of-function. Our findings provide evidence for a wider role of PTPN11 lesions in leukemogenesis, but also suggest a lineage-related and differentiation stage-related contribution of these lesions to clonal expansion.

Adolescent↗
PubMed2004

Synthesis, cytotoxicity, and apoptosis induction in human tumor cells by geiparvarin analogues.

A series of geiparvarin analogues modified on the unsaturated alkenyloxy bridge, where a H-atom replaced the 3'-Me group, were synthesized and evaluated against a panel of human tumor cell lines in vitro. These compounds demonstrated a stronger increase in growth inhibitory activity when compared to the parent compound geiparvarin (8). In particular, the activity increased even further in the series of demethylated compounds when a Me substituent in the coumarin moiety is introduced. On the contrary, the same modifications exerted on the parent compound led to an activity reduction. Interestingly, the new derivatives proved to be fully inhibitory to drug-resistant cell lines, thus suggesting that they are not subject to the pump-mediating efflux of antitumor drugs. On the basis of their cytotoxic profiles, the most-active compounds were selected for further biological evaluation. The extracellular acidification rate by the new geiparvarin analogues was measured with the Cytosensor microphysiometer. The new derivatives significantly increased the acidification rate during the 24-48 h of incubation in a concentration-dependent manner. Cell-cycle analysis, evaluated by flow cytometry, revealed a strong apoptotic induction by these compounds confirmed by DNA laddering and observation by electron microscopy. Interestingly, the apoptotic pathway did not appear to be mediated by the activation of caspase-3.

Apoptosis↗
PubMed2004

Association of cytogenetic abnormalities with detection of BCR-ABL fusion transcripts in children with T-lineage lymphoproliferative diseases (T-ALL and T-NHL).

Detection of Philadelphia chromosome (Ph) in childhood T-lineage acute lymphoproliferative disorders is a rare event. Additional cytogenetic abnormalities are particularly uncommon in ALL. We here report two cases with T lineage acute lymphoproliferative disorders (T-ALL and T-NHL) presenting with both cytogenetic alterations and BCR-ABL fusion transcripts, associated with an aggressive presentation and a poor outcome. We point out firstly on the cytogenetic aberrations, supporting the hypothesis of multi-lineage involvement of ALL expressing Ph chromosome; secondly, on the persistence of T-cell leukemic clone detected by minimal residual disease (MRD) analysis, despite of the early disappearance of BCR-ABL fusion transcript.

Adolescent↗
PubMed2004

Proapoptotic effect of hepatitis C virus CORE protein in transiently transfected cells is enhanced by nuclear localization and is dependent on PKR activation.

BACKGROUND/AIMS: HCV-CORE protein has been implicated in the regulation of apoptosis of infected cells acting as full-length or C-terminus deleted forms and resulting in both proapoptotic and antiapoptotic effects in different experimental conditions. METHODS: We have fused full-length and C-terminus deleted CORE with GFP to assess intracellular localization in transiently transfected cell lines and primary hepatocytes. Apoptosis of cells expressing different levels of chimeric proteins was quantified by cytometry. RESULTS: Full-length CORE localized mainly in the cytoplasm, but nuclear staining was also observed, being more evident in primary human hepatocytes. Nuclear staining only was observed in cells expressing truncated CORE. Full-length CORE induced apoptosis in approximately 15-20% of transfected cells with low expression and in approximately 40-50% of those with high expression of viral protein. Interestingly, 40-50% of cells transfected with truncated CORE underwent apoptosis, independently of protein expression levels. CORE-induced apoptosis was significantly reduced in the presence of a protein kinase R (PKR) inhibiting peptide and truncated CORE was able to enhance translocation of PKR into nucleoli where CORE/PKR colocalization was observed. CONCLUSIONS: These results suggest that nuclear forms of HCV-CORE are generated in vivo in primary hepatocytes and induce PKR-dependent apoptosis, a mechanism that might have a relevant role during natural infection.

Animals↗
PubMed2004

Acute leukemia subclassification: a marker protein expression perspective.

Improved leukemia classification and tailoring of therapy have greatly improved patient outcome particularly for children with acute leukemia (AL). Using immunophenotyping, molecular genetics and cytogenetics the low hanging fruits of biomedical research have been successfully incorporated in routine diagnosis of leukemia subclasses. Future improvements in the classification and understanding of leukemia biology will very likely be more slow and laborious. Recently, gene expression profiling has provided a framework for the global molecular analysis of hematological cancers, and high throughput proteomic analysis of leukemia samples is on the way. Here we consider classification of acute leukemia samples by flow cytometry using the marker proteins of immunophenotyping as a component of the proteome. Marker protein expressions are converted into quantitative expression values and subjected to computational analysis. Quantitative multivariate analysis from panels of marker proteins has demonstrated that marker protein expression profiles can distinguish MLLre from non-MLLre ALL cases and also allow to specifically distinguish MLL/AF4 cases. Potentially, these quantitative expression analyses can be used in clinical diagnosis. Immunophenotypic data collection using flow cytometry is a fast and relatively easily accessible technology that has already been implemented in most centers for leukemia diagnosis and the translation into quantitative expression data sets is a matter of flow cytometer settings and output calibration. However, before application in clinical diagnostics can occur it is crucial that quantitative immunophenotypic data set analysis is validated in independent experiments and in large data sets.

Acute Disease↗
PubMed2004

Microarray transcript profiling distinguishes the transient from the acute type of megakaryoblastic leukaemia (M7) in Down's syndrome, revealing PRAME as a specific discriminating marker.

Transient myeloproliferative disorder (TMD) is a unique, spontaneously regressing neoplasia specific to Down's syndrome (DS), affecting up to 10% of DS neonates. In 20-30% of cases, it reoccurs as progressive acute megakaryoblastic leukaemia (AMKL) at 2-4 years of age. The TMD and AMKL blasts are morphologically and immuno-phenotypically identical, and have the same acquired mutations in GATA1. We performed transcript profiling of nine TMD patients comparing them with seven AMKL patients using Affymetrix HG-U133A microarrays. Similar overall transcript profiles were observed between the two conditions, which were only separable by supervised clustering. Taqman analysis on 10 TMD and 10 AMKL RNA samples verified the expression of selected differing genes, with statistical significance (P < 0.05) by Student's t-test. The Taqman differences were also reproduced on TMD and AMKL blasts sorted by a fluorescence-activated cell sorter. Among the significant differences, CDKN2C, the effector of GATA1-mediated cell cycle arrest, was increased in AMKL but not TMD, despite the similar level of GATA1. In contrast, MYCN (neuroblastoma-derived oncogene) was expressed in TMD at a significantly greater level than in AMKL. MYCN has not previously been described in leukaemogenesis. Finally, the tumour antigen PRAME was identified as a specific marker for AMKL blasts, with no expression in TMD. This study provides markers discriminating TMD from AMKL-M7 in DS. These markers have the potential as predictive, diagnostic and therapeutic targets. In addition, the study provides further clues into the pathomechanisms discerning self-regressive from the progressive phenotype.

Acute Disease↗
PubMed2004

Recommended reporting format for flow cytometry diagnosis of acute leukemia.

Although flow cytometry is increasingly used as a tool to diagnose hematologic malignancies, the reporting format of acute leukemia immunodiagnosis is still imprecise and sometimes vague, often reflecting old guidelines. Thus, the purpose of the present work was to make the reporting format for the immunological diagnosis of acute leukaemia easy and clear to understand. This work represents part of a more articulated series of technical guidelines that the Italian Society for Cytometry (GIC) is currently processing. Thirteen separate recommendations, covering all aspects of an acute leukemia cytometry report, are listed. According to our suggestions, the report must contain clear statements about: 1. demographic identification of patient; 2. identification of the hospital or division sending the sample; 3. type of specimen (bone marrow aspirate, peripheral blood, other biological fluids); 4. timing of observation (first diagnosis or follow-up); 5. diagnostic hypothesis made by the sender; 6. list of antigens and type of immunofluorescence analysis carried out; 7. absolute number of cells in the sample; 8. quality of the sample, in terms of viability; 9. general description of the gating procedure; 10. immunophenotype of blast cells; 11. description of cells surrounding blasts; 12. diagnostic conclusions; 13. definition of an antigen panel (when applicable) for the detection of minimal residual disease. As an example of a final report we present a case of acute myeloid leukaemia with t(8;21) translocation; in filling this report, we followed all the 13 points of the checklist described in the paper.

Antigens, Neoplasm↗
PubMed2004

Imatinib mesylate (STI571) interference with growth of neuroectodermal tumour cell lines does not critically involve c-Kit inhibition.

A therapeutic role of STI571 (imatinib mesylate) has been anticipated in patients with c-Kit positive neuroectodermal tumors. We examined the efficacy of STI571 to inhibit expansion of c-Kit positive neuroectodermal tumor cell lines in vitro and in a mouse model inoculated with ES (Ewing sarcoma) derived tumor cells, and investigated the molecular mechanism of STI571 action. Eleven tumor lines of ES, PNET (primitive neuroectodermal tumors) and NB (neuroblastoma) were assayed in the presence of 1, 5, 10, 15, 20 or 30 micro M STI571 for 24, 48, 72 h and 7 days. The mechanism of STI571 action was investigated using a microphysiometer cytosensor that determines cellular metabolic rates in the presence of STI571. c-Kit and global protein phosphorylation was assayed by immunoprecipitation and a direct enzyme-linked immunoadsorbent assay after 72 h of 10 micro M STI571. Apoptosis was investigated by propidium iodide (PI), Annexin V staining and by enzymatic activity of caspase-3. Moreover, apoptotic gene expression was investigated using microarray technology. In nude mice, tumor volume and histology were analyzed in STI571 treated and untreated mice, and apoptotic gene expression analysis was performed on tumor masses. A decrease in cell proliferation and increase of cell apoptosis was caused by STI571 in a concentration- and time-dependent manner. Cytosensor microphysiometer and immunoprecipitation experiments demonstrated a time- and concentration-dependent decrease of cellular metabolic activity and global protein dephosphorylation after STI571 exposure. The inhibition by STI571 appeared at least to some extent independent of c-Kit inhibition since cells remained sensitive to SCF stimulation. Tumor volume was significantly reduced in STI571-treated mice compared to tumors from control inoculated non-treated mice. The apoptosis pathway in response to STI571 appeared not to be dependent on caspase activation, while gene expression profiles suggested accumulation of reactive oxygen species (ROS) resulting in cell death after exposure to STI571. The results point to the potential relevance of STI157 for neuroectodermal tumor therapy in view of its inhibitory effect on tumor cell growth, in spite of the observation that the inhibition of the c-Kit signaling pathway is not critically involved.

Animals↗
PubMed2003

Apoptosis and phosphatidylserine-mediated recognition during the take-over phase of the colonial life-cycle in the ascidian Botryllus schlosseri.

Colonies of the ascidian Botryllus schlosseri undergo recurrent generation changes in which adult zooids are gradually resorbed and replaced by new blastogenic generations. During these periods, known as take-over phases, programmed cell death, which, on the basis of morphological analysis is ascribed to apoptosis, occurs widely in zooid tissues. In the present report, we re-investigate cell death during the take-over process. Results confirm the occurrence of diffuse apoptosis, as evidenced by chromatin condensation, positivity to the TUNEL reaction and expression of phosphatidylserine on the outer leaflet of the plasma membrane. Apoptosis also occurs among haemocytes, and senescent blood cells are actively recognised and ingested by circulating professional phagocytes. Both phosphatidylserine and CD36, a component of the thrombospondin receptor, are involved in the recognition of apoptotic haemocytes, which fosters the idea that fundamental recognition mechanisms are well conserved throughout chordate evolution.

Animals↗
PubMed2003

Acquired mutations in GATA1 in neonates with Down's syndrome with transient myeloid disorder.

Transient myeloid disorder is a unique self-regressing neoplasia specific to Down's syndrome. The transcription factor GATA1 is needed for normal growth and maturation of erythroid cells and megakaryocytes. Mutations in GATA1 have been reported in acute megakaryoblastic leukaemia in Down's syndrome. We aimed to investigate changes in GATA1 in patients with Down's syndrome and either transient myeloid disorder (n=10) or acute megakaryoblastic leukaemia (n=6). We recorded mutations eliminating exon 2 from GATA1 in all patients with transient myeloid disorder (age 0-24 days) and in all with acute megakaryoblastic leukaemia (age 14-38 months). The range of mutations did not differ between patients with each disorder. Patients with transient myeloid disorder with mutations in GATA1 can regress spontaneously to complete remission, and mutations do not necessarily predict later acute megakaryoblastic leukaemia.

Child, Preschool↗
PubMed2003

DLX genes as targets of ALL-1: DLX 2,3,4 down-regulation in t(4;11) acute lymphoblastic leukemias.

Dlx genes constitute a gene family thought to be essential in morphogenesis and development. We show here that in vertebrate cells, Dlx genes appear to be part of a regulatory cascade initiated by acute lymphoblastic leukemia (ALL)-1, a master regulator gene whose disruption is implicated in several human acute leukemias. The expression of Dlx2, Dlx3, Dlx5, Dlx6, and Dlx7 was absent in All-1 -/- mouse embryonic stem cells and reduced in All-1 +/- cells. In leukemic patients affected by the t(4;11)(q21;q23) chromosomal abnormality, the expression of DLX2, DLX3, and DLX4 was virtually abrogated. Our data indicate that Dlx genes are downstream targets of ALL-1 and could be considered as important tools for the study of the early leukemic cell phenotype.

Animals↗
PubMed2003

Non-radiolabelled PCR consensus primers and automatic sequencing enable rapid identification of tumor-specific V(H) CDR3 in aggressive B-cell malignancies.

Even though the results of current therapy are improved for B-cell acute lymphoblastic leukemia (B-ALL) and Burkitt's lymphoma (BL), prognosis of relapsed mature B-ALL and BL still remain extremely poor. In this study, we investigated the possibility of applying the use of non-radiolabelled PCR consensus primers and automatic sequencing for the rapid identification of the tumor-specific V(H) CDR3 nucleotide sequence, in mature B-ALL and BL. RNA was extracted from four consecutive, unselected samples from BL cases and three consecutive, unselected samples from mature B-ALL cases. The feasibility of the identification of the tumor-specific V(H) CDR3 nucleotide sequence was then assessed by using non-radiolabelled PCR consensus primers with automatic sequencing. The tumor-specific V(H) CDR3 nucleotide sequence was successfully identified for all seven patients (3 mature B-ALL and BL). The time required was substantially lower than that of the other methods previously published, despite the poor quality of some of the samples. The procedure showed rapidity, reliability and reproducibility. The characteristics of the methodology applied widen the possibility of developing anti-idiotypic therapeutic strategies, even in these B-cell malignancies.

Automation↗
PubMed2003

Osteonecrosis: An emerging complication of intensive chemotherapy for childhood acute lymphoblastic leukemia.

BACKGROUND AND OBJECTIVES: Osteonecrosis (ON) is a potentially disabling complication of combination chemotherapy including high doses of steroids. The incidence and main risk factors for symptomatic ON have been investigated in a large group of children treated with high-dose steroids, prednisone and dexamethasone for childhood acute lymphoblastic leukemia (ALL). DESIGN AND METHODS: From May 1995 to December 1999, 1421 patients <18 years old, with newly diagnosed non-B ALL, were registered in the AIEOP-ALL 95 study. Their data were reviewed to identify patients who developed symptomatic ON. For those who were positively identified additional data were requested concerning ON-related symptoms, treatment and outcome. RESULTS: Overall, 15 of the 1421 patients developed symptomatic ON (1.1%) in a total of 29 sites. The estimated 5-year cumulative risk for clinically diagnosed ON was 1.6% (SE 0.4). The incidence was significantly higher among females (p=0.01) and older patients, with a peak rate of 7.4% (2.3) among those aged 10 to 17 years (p<0.0001). When the two factors, i.e. age and gender were combined, there was a striking increase in the risk among female patients aged 10 to 17 years. The median time between the diagnosis of ALL and that of ON was 17 months (range 8-45). The hip was the most frequently involved (19/29) site. INTERPRETATION AND CONCLUSIONS: Symptomatic ON occurred in only 1.1% of patients treated with BFM-type, intensive chemotherapy for childhood ALL. Female adolescents appear to be the subset of patients with the highest risk of ON, especially when categorized as having high risk leukemia and thus administered higher cumulative doses of dexamethasone.

Adolescent↗