Human monocytic leukemia expresses low levels of asparagine synthase and is potentially sensitive to L-asparaginase.
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Asparaginase↗
Biomedical subjects
G Masera
Publications and source records attributed to G Masera.
Hepatitis C virus infection and liver failure in patients undergoing allogeneic bone marrow transplantation.
The role of hepatitis C virus (HCV) infection in severe liver failure (LF) following bone marrow transplantation is still uncertain. We therefore decided to determine the presence of HCV-RNA in 31 patients who died of severe LF after BMT and in 26 matched BMT controls who did not develop LF. HCV-RNA was identified by polymerase chain reaction and anti-HCV by second generation enzyme-linked immunoassay and by 4-band recombinant immunoblotting assay in serum samples obtained before and after BMT. Biochemical and clinical parameters of liver disease were obtained by reviewing clinical records. LF developed at a median interval of 80 days (20-570) from transplantation and was clinically assessed as VOD (n = 7), liver GVHD (n = 5) or hepatitis (n = 19). HCV-RNA was detected, respectively, in 15/31 (48%) and in 12/26 (46%) of LF patients and controls (P = 0.9). Conversely, the risk of dying of LF was 62% and 53% (P = 0.5) respectively, for HCV-RNA positive and negative patients. Anti-HCV profile did not correlate with viremia, nor with type of liver disease. These findings indicate that, despite a 47% prevalence of HCV infection in our series, HCV-RNA positivity was neither a predictor of VOD nor a marker for life-threatening liver disease.
Adolescent↗
Determination of L-asparagine in biological samples in the presence of L-asparaginase.
The antileukaemic efficacy of L-asparaginase is related to the ability of the enzyme to induce the complete disappearance from plasma of L-asparagine, an amino acid essential to lymphoblastic leukaemia cells. It is not feasible to monitor L-asparagine plasma levels in patients under L-asparaginase treatment using the usual analytical procedures as the enzyme continues the hydrolysis of L-asparagine after blood sampling and during plasma extraction. A method was therefore developed for the determination of L-asparagine in patients receiving L-asparaginase. Sulphosalicylic acid is added to blood samples to deproteinize and inactivate L-asparaginase rapidly. The samples are then analysed by HPLC using a Novapack C18 column and fluorescence detection. With the same method L-asparagine is determined in blood cells and, by difference, plasma levels are calculated. This method is highly specific and sufficiently simple and sensitive for clinical use.
Asparaginase↗
Suppression of juvenile chronic myelogenous leukemia colony growth by interleukin-1 receptor antagonist.
Bone marrow (BM) and peripheral blood (PB) cells from patients with juvenile chronic myelogenous leukemia (JCML) exhibit spontaneous in vitro proliferation. Several cytokines including granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 beta (IL-1 beta), and tumor necrosis factor alpha (TNF alpha) have been implicated in supporting the growth of leukemic monocyte-macrophage colonies either by autocrine or paracrine pathways. In seven untreated JCML patients, we investigated the role of IL-1 in the spontaneous growth of these cells by specifically blocking IL-1 receptors. The IL-1 receptor antagonist (IL-1 Ra) was added to the clonogenic assays, and in each case significant (mean = 63%, range = 35% to 82%) inhibition of spontaneous proliferation was observed. Uncultured circulating cells from PB or BM of four out of five patients expressed IL-1 beta-specific mRNA and secreted the protein into the culture supernatants. Moreover, by means of reverse transcriptase-polymerase chain reaction (RT-PCR), we demonstrated that most of the spontaneously growing leukemic colony-forming unit cells (CFU-C) obtained from BM cells of two patients were positive for the presence of the IL-1 beta-specific mRNA. Despite the presence of a measurable amount of GM-CSF in JCML cell culture supernatants, GM-CSF-specific mRNA in CFU-C cells of four cases was not detected by RT-PCR. These data further support a central role for IL-1 beta in the pathogenesis of JCML and suggest that the use of IL-1 Ra could represent a novel therapeutic strategy against this disorder.
Adult↗
Leukemic ophthalmopathy: a report of 21 pediatric cases.
A multicentric retrospective study on leukemic ophthalmopathy (LO) is reported. It includes 21 patients, 16 males and 5 females, with acute leukemia (AL) observed in 10 SIOP centers. LO developed in three patients at the time of diagnosis of AL; five patients were in first complete remission (three off therapy); four patients were in second or third remission; and nine were in combined relapse. Most frequent symptoms were blurred vision, photophobia, and ocular pain. Two patients with acute nonlymphoblastic leukemia died before treatment; another underwent bone marrow transplantation; one patient with B-cell acute lymphoblastic leukemia (B-ALL) treated with chemotherapy and radiotherapy died 4 months after LO; the remaining 17 children were treated according to different schedules with (10) or without (7) radiotherapy on the affected eye. Twelve patients achieved ocular remission and four of these had a second ocular relapse. Complete remission after LO treatment lasting for more than 3, 7, 24, 29 months was observed in four patients. The authors conclude that cure is possible in patients who had LO in first complete remission treated with chemotherapy and radiotherapy at high dose on the affected eye.
Acute Disease↗
Double target in situ hybridization applied to the study of numerical aberrations in childhood acute lymphoblastic leukemia.
To test the feasibility of using fluorescent in situ hybridization (FISH) on interphase and metaphase cells to detect numerical aberrations in childhood acute lymphoblastic leukemia (ALL), we analyzed bone marrow of 15 patients with cytogenetically documented hyperdiploidy with more than 50 chromosomes at diagnosis. Patients were selected on the basis of being trisomic or tetrasomic for chromosomes 17 and/or 18 as determined by G-banded chromosome analysis. We performed a double target FISH using DNA probes specific for the centromeric region of chromosomes 17 and 18, respectively. The numerical changes regarding chromosome 17 and/or 18 identified by FISH on metaphases were found in all cases analyzed by FISH on interphase nuclei. In 8 of 15 patients, FISH on interphase nuclei demonstrated the presence of one or more groups of cells with different combinations of trisomy and tetrasomy of the two chromosomes investigated, beside the ones detected on metaphases. Overall our findings indicate that interphase FISH analysis could be a useful method to detect the presence of numerical aberrations of two chromosomes simultaneously in bone marrow and peripheral blood specimens of ALL as an adjunct to conventional cytogenetic investigation or metaphase FISH.
Child↗
Prognostic relevance of pretreatment proliferative rapidity of marrow blast cells in childhood acute lymphoblastic leukaemia.
Cell proliferation rate is a well-established prognostic factor in cancer, but it has not been considered to identify the risk group of childhood acute lymphoblastic leukaemia (ALL) at presentation. We carried out a study to demonstrate the prognostic importance of the rapidity of cell proliferation in patients with ALL. To measure the rapidity of cell proliferation we used the parameter relative to the area of silver-stained nucleolar organiser regions (AgNORs) as evaluated by morphometric analysis on smeared marrow blast cells. The mean AgNOR area of leukaemic marrow cells was measured in 119 children. By using a cut-off value of 3 microns2, we identified a group of 91 children with low proliferating blast activity (mean AgNOR value 2.11 microns2) and a group of 28 children with high proliferating activity (mean AgNOR value 3.29 microns2). The group of patients with a mean AgNOR value > 3 microns2 was characterised by a higher number of deaths, more frequent relapse and shorter time interval to relapse than the group of patients with mean AgNOR value < 3 microns2 (P < 0.01). Multivariate analysis performed to include T-cell immunophenotype, FAB morphology, leucocyte count and presence of mediastinal mass showed that the mean AgNOR value was the only independent predictor of unfavourable event-free survival probability (P > 0.01). Our results indicate that the rapidity of marrow blast cell proliferation is an important prognostic parameter in childhood ALL and should be routinely introduced in the group risk definition.
Bone Marrow↗
Evidence against the role of hepatitis C virus in severe liver damage occurring early in the course of acute leukemia in children.
Severe liver damage revealed by a sharp transaminase elevation may be seen in patients with leukemia. This may be due to several possible causes, including viral hepatitis, chemotherapy-induced hepatotoxicity and leukemic infiltration. HCV infection may be suspected to play a relevant role as these patients are often heavily transfused after the onset of their hematologic disorder. We have therefore examined the role of HCV in 15 children with leukemia who developed severe liver damage shortly after the diagnosis of leukemia. All patients were tested for HCV-RNA by the polymerase chain reaction at the time of peak SGPT elevation and for anti-HCV on serial serum samples taken thereafter. Only one patient (6.6%) showed hepatitis C viremia and none developed confirmed anti-HCV positivity during follow-up, suggesting that HCV had not played a major role in causing these severe episodes of liver necrosis. This is in agreement with observations made in non-immunocompromised patients in whom fulminant hepatitis is only exceptionally due to HCV.
Acute Disease↗
Acute promyelocytic leukemia in children: experience of the Italian Pediatric Hematology and Oncology Group (AIEOP).
Scanty information is available on acute promyelocytic leukemia (APL) in children, and whether differences are present with respect to the adult form. The experience of the Italian Pediatric Hematology and Oncology Group (AIEOP) will be presented with respect to the following aspects: 1. Incidence of APL. The incidence of APL is generally considered to account for 3-9% of acute myelogenous leukemia (AML) in children and approximately 10-15% in adults. Recently a single Italian pediatric institution reported that APL constituted one third of observed acute nonlymphocytic leukemia (AnLL) cases. Data from the AIEOP cooperative study group have confirmed that APL in Italy is more frequently observed in children as compared to other countries. Environmental and/or genetic factors should be considered to explain such differences. 2. Diagnosis of M3v. The clinical and biological features of the largest series of childhood M3v will be presented and the problems encountered in the proper separation of 'classic' M3 and M3v in children will be discussed. 3. Clinical Aspects. The clinical features of the APL patients enrolled in the AIEOP study groups since 1989, will be presented with emphasis on the recent experience with the use of all-trans retinoic acid. 4. Analysis of PML/RAR alpha Fusion Transcripts. An RT-PCR analysis of 32 pediatric APL cases from cryopreserved bone marrow samples has been performed. It is concluded that APL in children did not differ significantly from the adult form, with the exception of a higher incidence of PML bcr3 breakpoint.
Age Factors↗
Acute promyelocytic leukemia in children: experience of the Italian Pediatric Hematology and Oncology Group (AIEOP).
Scanty information is available on acute promyelocytic leukemia (APL) in children, and whether differences are present with respect to the adult form. The experience of the Italian Pediatric Hematology and Oncology Group (AIEOP) will be presented with respect to the following aspects: 1. Incidence of APL. The incidence of APL is generally considered to account for 3-9% of acute myelogenous leukemia (AML) in children and approximately 10-15% in adults. Recently a single Italian pediatric institution reported that APL constituted one third of observed acute nonlymphocytic leukemia (AnLL) cases. Data from the AIEOP cooperative study group have confirmed that APL in Italy is more frequently observed in children as compared to other countries. Environmental and/or genetic factors should be considered to explain such differences. 2. Diagnosis of M3v. The clinical and biological features of the largest series of childhood M3v will be presented and the problems encountered in the proper separation of 'classic' M3 and M3v in children will be discussed. 3. Clinical Aspects. The clinical features of the APL patients enrolled in the AIEOP study groups since 1989, will be presented with emphasis on the recent experience with the use of all-trans retinoic acid. 4. Analysis of PML/RAR alpha Fusion Transcripts. An RT-PCR analysis of 32 pediatric APL cases from cryopreserved bone marrow samples has been performed. It is concluded that APL in children did not differ significantly from the adult form, with the exception of a higher incidence of PML bcr3 breakpoint.
Adolescent↗
Detection of ALL-1/AF4 fusion transcript by reverse transcription-polymerase chain reaction for diagnosis and monitoring of acute leukemias with the t(4;11) translocation.
The chromosomal breakpoints of t(4;11) translocation of acute lymphoblastic leukemia (ALL) have been recently identified at molecular level and shown to involve the AF4 (FEL) gene on chromosome 4 and the ALL-1 (MLL, Hrx) gene on chromosome 11. The ALL-1/AF4 fusion gene is transcribed into a chimeric mRNA. Using primer sets derived from ALL-1 and AF4 cDNAs by reverse transcription-polymerase chain reaction (RT-PCR), we were able to amplify the breakpoint sites of the fusion transcript of all 15 ALL cases with karyotypic or molecular evidence of the t(4;11). DNA fragments of different size were obtained as the consequence of different breakpoints on chromosome 11 and the presence of alternative splicing of ALL-1 exon 8. The feasibility of monitoring the residual cells carrying the t(4;11) in 2 ALL patients with different clinical outcome was evaluated. Overall, the presented results provide evidence that RT-PCR can be used as a rapid method for detecting this chromosomal abnormality and following the patient's response to therapy.
Adolescent↗
Risk-directed therapy for childhood acute lymphoblastic leukemia. Results of the Associazione Italiana Ematologia Oncologia Pediatrica '82 studies.
BACKGROUND: In 1982, the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) started its third-generation study, aiming to improve previous results obtained by AIEOP '79 study and to deliver a standardized treatment to most Italian children with acute lymphoblastic leukemia (ALL). METHODS: We treated 902 children (older than 1 year and younger than 15 years of age) with newly diagnosed ALL in multicenter studies of risk-directed therapy (111 low risk [LR] from Study 8201; 570 average risk [AR] from Study 8202; and 117 and 104 high risk [HR] from Studies 8303 and 8503, respectively). Induction therapy was composed of vincristine, prednisone, and asparaginase for LR or AR patients and these agents plus daunorubicin, (Study 8503) or vincristine, prednisone, cytarabine, and intermediate-dose methotrexate (Study 8303) for HR patients. Central nervous system (CNS) preventive therapy consisted of intrathecal methotrexate only (LR), intrathecal methotrexate plus 18 Gy cranial irradiation (AR and HR Study 8503), or high-dose (HD) cytarabine (HR Study 8303). Reinduction therapy was vincristine/prednisone/daunorubicin for AR patients with cyclophosphamide added for HR patients in Study 8303 and HD asparaginase in Study 8503. LR patients did not receive intensification therapy. Continuation therapy comprised 6-mercaptopurine plus methotrexate and monthly pulses with vincristine plus prednisone for all patients, except for HR patients in Study 8303 who also received teniposide plus cytarabine. Weekly HD asparaginase was also given in Study 8503. Duration of treatment was 24 months for Studies 8201 and 8202, 15 months for Study 8303, and 22 months for Study 8503. The overall complete remission (CR) rate was 94.7% (97.3% for LR, 94.9% for AR, and 93.2% for HR). RESULTS: Overall 7-year event-free survival (EFS) was 53.6% (standard error [SE], 1.8). EFS was 60.8% in LR (SE, 4.7), 60.6% in AR at 7 years (SE, 4.7), and 18.5% in Study 8303 (HR) at 5 years (SE, 3.8). Because of the poor result in HR patients, a successor study (8503) was developed that yielded a 5-year EFS of 46.1% (SE, 5.1). Site-specific relapse rates were 18.5% (LR), 13.4% (AR), 35.1% (HR on 8303), and 18.3% (HR in Study 8503) for bone marrow and 9.2%, 7.9%, 17.5%, and 19.3%, respectively, for the CNS (isolated). Isolated testicular relapse was observed in 3.9% of male patients. CONCLUSIONS: This risk-directed therapy cured at least 50% of patients with ALL with relatively nonintensive therapy. The 80% overall survival rate for LR and AR patients at 7 years suggested that the total cure rate may be higher than 50% because of the significant salvage rate for patients who received antimetabolite-based therapy initially.
Adolescent↗
Hepatitis C virus serum markers and liver disease in children with leukemia during and after chemotherapy.
The pattern of hepatitis C virus (HCV) serum markers and liver disease was investigated in 11 leukemic children showing anti-HCV reactivity at least once during long-term observation to define the role of HCV infection and the behavior of HCV serologic markers in this patient cohort. Antibodies to HCV by first- and second-generation enzyme-linked immunosorbent assay (ELISA) and by second-generation (four antigens) recombinant immunoblotting assay (RIBA) and HCV-RNA by nested polymerase chain reaction (PCR) were serially examined in serum. Liver disease was defined according to transaminase levels. Seven of 11 patients were found HCV-RNA positive during chemotherapy and after blood transfusion, 3 of 11 became viremic during follow-up, and 1 of 11 was always HCV-RNA negative. Seroconversion to anti-HCV positivity by second-generation ELISA occurred in all the HCV-RNA positive children either during or after chemotherapy. Alanine aminotransferase (ALT) levels were elevated in all the HCV-RNA positive patients during antileukemic treatment and normalized in seven of them after therapy withdrawal, despite persisting viremia. These results indicate that HCV-RNA testing by polymerase chain reaction is required to correctly identify HCV infection in patients with leukemia while on chemotherapy. Viremia did not correlate with ALT levels and anti-HCV patterns.
Alanine Transaminase↗
ALL-1 gene at chromosome 11q23 is consistently altered in acute leukemia of early infancy.
Early infancy (< 1 year of age), massive tumor cell burden, and extremely poor prognosis are characteristic features of a particular subset of childhood acute leukemias (AL). In these cases, chromosome aberrations at the 11q23 band are the most frequently reported cytogenetic abnormalities. We have recently cloned a genetic locus named ALL-1, in which DNA breakpoints are clustered in leukemic patients with 11q23 aberrations. Analysis of the ALL-1 genomic configuration in DNA from 15 infants with AL showed specific ALL-1 rearrangements in 12 cases (80%), including 5 with normal karyotypes. These findings indicate that a consistent genetic defect underlies this particular leukemic subset.
Acute Disease↗
Diagnosis and incidence of acute promyelocytic leukemia (FAB M3 and M3 variant) in childhood.
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Child↗
Allogeneic bone marrow transplantation for myelodysplastic syndromes of childhood: report of three children with refractory anemia with excess of blasts in transformation and review of the literature.
Myelodisplastic syndromes (MDS) in childhood deserve a negative prognosis even though disease-free survival has been obtained in 20% of cases by using aggressive chemotherapy. We describe three children with refractory anemia with excess of blasts in transformation (RAEB-T) who underwent bone marrow transplantation (BMT). We also reviewed 21 additional cases (median age was 8 years) with primary MDS recently reported in the literature with the aim of clarifying the role of BMT in treating these patients. Twelve of the 24 children were long-term survivors and free from disease at a median time of 1,320 days (range 302-2,340). There were five relapses, two graft failures, two early deaths (one VOD, one severe GVHD), and three late deaths (two respiratory diseases, one severe GVHD). We didn't find any correlation between karyotype and outcome. In conclusion, so far BMT seems to be the most valid treatment of childhood primary MDS. However, since the major causes of failure were regimen-related toxicity or recurrence of the disease after BMT, it must be pointed out that, when a compatible donor even unrelated is available, BMT for childhood MDS should be given as soon as possible or at any rate prior to blastic crisis.
Adolescent↗
SIOP Working Committee on Psychosocial Issues in Pediatric Oncology.
Recognizing the importance of psychosocial issues in the care and cure of the child with cancer, the board of the International Society of Pediatric Oncology (SIOP) in 1991 constituted a Working Committee on Psychosocial Issues in Pediatric Oncology, with Giuseppe Masera as chair and John Spinetta as co-chair. This committee met for the first time in Rhodes, Greece, in October 1991. The committee discussed various psychosocial issues and developed a document on Aims and Recommendations, summarizing the experiences of major centers. This document was approved by the SIOP board, which recommended diffusion of the document to the pediatric oncology community.
Child↗
Cytotoxic activity and mechanism of action of 5-Aza-2'-deoxycytidine in human CML cells.
We investigated the cytotoxic activity and some aspects of the mode of action of 5-aza-2'-deoxycytidine (Aza-dC) in 21 primary cultures of leukemic cells freshly obtained from patients with chronic myeloid leukemia (CML) in blast crisis. The cytotoxic potency of Aza-dC was comparable or even greater than that of 1-beta-D-arabinofuranosylcytosine (Ara-C) in most cases, suggesting that this drug has potential in the therapy of blast crisis of CML. Drug incorporation into DNA was evaluated by exposing leukemic cells simultaneously to 3H-Aza-dC at the concentration of 0.1 micrograms/ml and 14C-thymidine (TdR) used as internal standard. Incorporation of Aza-dC into DNA was detectable in all cases. In 17 samples we evaluated the DNA integrity of leukemic cells exposed to Aza-dC using alkaline elution techniques. The drug caused a detectable amount of DNA alkali labile sites (ALS). DNA-ALS increased in cells exposed to Aza-dC concentrations from 0.1 to 1 microgram/ml but did not further increase at 10 micrograms/ml. A plateau in the levels of DNA-ALS was also seen in human K562 cells exposed to increasing concentrations of Aza-dC from 5 to 10 micrograms/ml, whereas in these cells Aza-dC incorporation into DNA increased with increasing Aza-dC concentrations. Therefore, DNA-ALS caused by Aza-dC are not simply the result of the chemical decomposition of azacytosine molecules incorporated into DNA, but are presumably the result of a saturable DNA repair mechanism (e.g., glycosylases) leading to formation of the apyrimidinic sites.
Antineoplastic Agents↗