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Biomedical subjects

A Biondi

Publications and source records attributed to A Biondi.

At least 163 records · Page 9Linked to original sources
PubMed1995

Autologous PBSC transplant for late onset AML after mafosfamide-purged and TBI-containing autologous BMT.

The prognosis of AML patients who fail autologous BMT and lack a donor for a salvage allogeneic BMT is very poor. We administered an alternative drug treatment including autologous PBSC transplant to a child who relapsed with AML 4 years after a mafosfamide-purged and TBI-containing BMT for second remission AML. Treatment comprised induction-consolidation with 'short' ICE courses (idarubicin-Ara C-etoposide for 2 days), high-dose CY plus G-CSF with collection of CD34+ PBSC and myeloablative treatment with high-dose mitoxantrone/BEAM supported by autologous PBSC reinfusion. The outcome was complete response, lasting 24 months. The patient died in remission of drug-related cardiotoxicity. This report emphasizes the possibility of a secondary AML after mafosfamide-purge autologous BMT, and documents the feasibility of an autologous PBSC transplant in such a high risk setting.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Reciprocal translocation t(12;13)(p13;q14) in acute nonlymphoblastic leukemia: report and cytogenetic analysis of two cases.

Two cases of acute nonlymphoblastic leukemia with a reciprocal translocation t(12;13)(p13;q14) are described. Both patients were male adults with a diagnosis of M0 FAB type. Beside standard cytogenetic analysis, we applied fluorescence in situ hybridization (FISH) in order to investigate the position of the RB gene with respect to the breakpoint at 13q14. Our results showed that the RB gene was proximal to the breakpoint, but, apparently, not split in either case.

Adult↗
PubMed1994

Determination of orally administered all-trans-retinoic acid in human plasma by high-performance liquid chromatography.

All-trans-retinoic acid (RA) is used successfully in the treatment of acute promyelocytic leukaemia (APL), although unexplained relapses occur in many of the patients. Pharmacokinetic studies may help in understanding the mechanism of resistance to RA and a simple and rapid procedure for its determination in biological samples may be advantageous. A high-performance liquid chromatographic procedure is described, involving one-step extraction of RA from plasma, isocratic elution from a reversed-phase column (LiChrosorb RP-18, 5-microns particle size) and UV detection at 340 nm. The calibration graph is linear over a wide range and the limit of detection is approximately 10 ng/ml, using 0.5 ml of human plasma. The method is selective for RA, accurate and robust and thus suitable for the routine analysis of plasma samples from patients undergoing RA therapy. Analysis of plasma in a patient on RA therapy (45 mg/m2 per day) confirmed that during continuous treatment with RA the drug plasma concentrations are markedly lower at the time of relapse than on the first day of treatment.

Administration, Oral↗
PubMed1994

Heteroduplex analysis of T-cell receptor gamma gene rearrangements for diagnosis and monitoring of cutaneous T-cell lymphomas.

The possibility to detect markers of T-cell clonality at the T-cell receptor (TCR) beta and gamma loci in skin biopsy samples has proven to be helpful for the often difficult clinical and immunohistochemical diagnosis of cutaneous T-cell lymphoma (CTCL). However, particularly at the early stage of the neoplastic infiltration, an emerging clonal pattern at Southern may be obscured by the germline TCR configuration of the predominant dermal and epidermal cell component. Additionally, multiple TCR gamma rearranged bands of variable intensity are often observed, either in the presence or in the absence of a major clone. To overcome these difficulties, we have investigated the T-lymphocyte clonality in selected patients with variable signs of CTCL by means of heteroduplex analysis of the amplified TCR gamma VJ junctions, separated in nondenaturing polyacrylamide gel. This technique has several advantages over standard Southern blot because it is simple, rapid, not radioactive, and likely more sensitive than other polymerase chain reaction-based procedures. In particular, the cases with uncertain or contradictory TCR beta and gamma patterns were solved by the heteroduplex analysis, showing homoduplex or heteroduplex bands of clonal nature. The direct sequence of the VJ junctions, easily obtained from the homoduplex or heteroduplex bands, allowed us to confirm the same clonal marker in two apparently different skin lesions and in different biopsy samples obtained from the same patients, either at the same or different time points, thus emphasizing the utility of this method in monitoring CTCL clinical progression.

Adult↗
PubMed1994

Analysis of p53 gene mutations in acute myeloid leukemia.

We have previously reported the absence of mutations within exons 5-9 of the p53 gene in a panel of 30 cases of acute promyelocytic leukemia (APL), which represent the M3 FAB type of acute myeloid leukemia (AML). In the present report, we extend our analysis of p53 gene mutations to 70 cases of AML representative of the other FAB types of the disease, including M1 (16 cases), M2 (20 cases), M4 (17 cases), M5 (12 cases), and M6 (5 cases). DNAs were analyzed for p53 gene mutations in exons 5 to 9 by polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP), and direct sequencing of PCR-amplified products. Mutant p53 alleles were detected in 5 of 70 cases; 1 case in exon 5, 2 cases in exon 6, and 2 cases in exon 7. The alterations of the p53 gene were represented by point mutation leading to an amino acid substitution in four cases, and deletion in the remaining case. In four of the five cases, direct sequencing indicated the loss of the normal p53 allele; in the remaining case, two mutations were detected, presumably involving both p53 alleles. Three cases showed mutations at diagnosis; in the remaining two, the mutations were observed in clinical relapse but not at diagnosis. Our results confirm the relatively low incidence of p53 mutations in AML and further support the evidence that p53 plays a role in leukemogenesis through a recessive mechanism (two-hit model) of inactivation of tumor suppressor activity.

Acute Disease↗
PubMed1994

Polymerase chain reaction (PCR) approach for the evaluation of minimal residual disease in acute leukemia.

Evaluation of minimal residual disease (MRD) in different forms of acute leukemias is an expanding field of experimental hematology. Several strategies and techniques, including cytomorphology, immunophenotype and karyotype, have been applied to evaluate MRD, but molecular biology has provided more sensitive and accurate tools to detect the neoplastic clones. This concise review summarizes some of the technical aspects and pitfalls associated with different molecular approaches such as the analysis of clonospecific DNA sequences in lymphoid malignancies and the demonstration of chimeric genomic products generated by chromosomal translocations. The feasibility, specificity and clinical relevance of all these studies will be briefly discussed.

Acute Disease↗
PubMed1994

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↗
PubMed1994

Clinical relevance of the PML/RAR-a gene rearrangement in acute promyelocytic leukaemia.

The molecular mechanisms underlying the t(15;17) cytogenetic translocation of acute promyelocytic leukaemia (APL) have been recently elucidated. Together with new insights into the understanding of APL pathogenesis, such investigations also provided the availability of a novel leukemia-specific marker to be used for both diagnostic and monitoring studies. The chromosome breakpoints of the t(15;17) have been shown to involve the retinoic acid receptor alpha (RAR-a) gene and the newly described PML gene on chromosomes 17 and 15, respectively. Rearrangements of these loci are found in virtually 100% of APLs, including the microgranular variant subtype and cases displaying apparently normal karyotypes. In cases with ambiguous morphology, molecular diagnosis may therefore enable the prompt administration of APL-specific therapies, such as all-trans retinoic acid. Significantly, clinical response to this differentiating agent is predictable based on the presence of the specific PML/RAR-a rearrangement. Appropriate oligoprimers complementary to PML and RAR-a sequences nearby the DNA breakpoints may be successfully used in PCR experiments to amplify the PML/RAR-a hybrid gene and sensitively detect minimal residual disease. Preliminary PCR studies indicate that this approach might indeed prove a very important and reliable prognostic indicator in the follow up monitoring of APL patients. Early identification of impending relapse by PCR may suggest the use of additional treatment in patients at risk and significantly increase the probability of cure of the disease.

Chromosomes, Human, Pair 15↗
PubMed1994

Monitoring of treatment outcome in acute promyelocytic leukemia by RT-PCR.

A rearrangement between the PML and RAR-alpha genes underlies the acute promyelocytic leukemia (APL)-specific t(15;17) translocation, leading to the production of a chimeric mRNA. Recent development of a reverse-transcription polymerase chain reaction (RT-PCR) assay for the PML/RAR-alpha hybrid has proven useful for rapid diagnosis and monitoring of minimal residual disease (MRD) in APL patients. Preliminary studies in which the prognostic significance of RT-PCR was evaluated indicate that this test may identify patients at high risk of relapse.

Hematologic Diseases↗
PubMed1994

Monitoring of treatment outcome in acute promyelocytic leukemia by RT-PCR.

A rearrangement between the PML and RAR-alpha genes underlies the acute promyelocytic leukemia (APL)-specific t(15;17) translocation, leading to the production of a chimeric mRNA. Recent development of a reverse-transcription polymerase chain reaction (RT-PCR) assay for the PML/RAR-alpha hybrid has proven useful for rapid diagnosis and monitoring of minimal residual disease (MRD) in APL patients. Preliminary studies in which the prognostic significance of RT-PCR was evaluated indicate that this test may identify patients at high risk of relapse.

Chromosomes, Human, Pair 15↗
PubMed1994

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↗
PubMed1994

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↗
PubMed1994

Molecular variants of the 1;19 chromosomal translocation in pediatric acute lymphoblastic leukemia (ALL).

The t(1;19)(q23;p13), a non-random chromosome rearrangement associated with childhood pre-B acute lymphoblastic leukemia (ALL), results at molecular level in the hybrid E2A-PBX1 gene. This gene is expressed in a typical set of fusion transcripts and oncogenic chimeric proteins. However, the occurrence of t(1;19) molecular variants has been recently suggested. In an attempt to identify these variants, we analyzed 25 pediatric cases of pre-B cIg+ cell ALL. We used Southern blot analysis to detect E2A gene rearrangements and RT-PCR to detect chimeric E2A-pbx1 transcripts. In addition to seven cases with the molecular pattern usually associated with the t(1;19), we identified three molecular variants. In one case, a variant E2A-pbx1 transcript showed 27 additional base pairs inserted in frame at the junction site. In two cases, Southern blot evidenced the expected E2A gene rearrangements. However, extensive RT-PCR analysis failed to detect any E2A-pbx1 transcript. These findings led us to hypothesize that a gene other than PBX1 might be involved in these 1;19 variant translocations.

Base Sequence↗
PubMed1994

Expression of GATA-1 mRNA in human myeloid leukemic cells.

Expression of the transcription factor GATA-1, which regulates several erythroid specific genes and possibly also some megakaryocytic genes, has been previously detected in normal erythroblasts, megakaryocytes, and basophils, and in some myeloid cell lines. It has been suggested that GATA-1 may be first expressed in a common progenitor and then further activated during erythroid-megakaryocytic and basophilic differentiation and repressed during myeloid maturation. We investigated GATA-1 mRNA expression in highly purified leukemic blasts representing different lineages and stages of myeloid differentiation and in a recently established leukemic cell line, GF-D8, which exhibits morphological, cytochemical and immunophenotypic characteristics of early myeloid progenitor cells. We found GATA-1 expression in five of five myeloid and in one megakaryocytic blast crisis of CML, in four of six cases of myelomonocytic leukemias (M4 according to FAB classification), in one case of erythroleukemia (M6), whereas lymphoid blast crisis of CML and all other FAB groups were completely negative. In addition, a low level of GATA-1 mRNA was also expressed by the GF-D8 cell line. These data further support the hypothesis that GATA-1 expression may occur not only in erythroid and megakaryocytic progenitors, but also in early myeloid progenitors, and then be further regulated during lineage-specific maturation.

Acute Disease↗
PubMed1993

Absence of reverse transcription-polymerase chain reaction detectable residual disease in patients with acute promyelocytic leukemia in long-term remission.

Hybrid fusion genes are specific tumor markers of several leukemic subtypes. The use of reverse transcription-polymerase chain reaction (RT-PCR) to amplify chimeric cDNAs allows sensitive detection of the neoplastic clone for diagnostic and monitoring studies in these leukemias. Nonetheless, the clinical relevance of minimal residual disease (MRD) evaluation by PCR remains controversial. In this study, 9 patients (pts) with acute promyelocytic leukemia (APL) in long-term remission for 4 to 12 years were analyzed for the presence of MRD by RT-PCR amplification of the specific PML/RAR-alpha fusion gene. Seven pts had been treated with conventional chemotherapy (CHT) alone, 1 had undergone allogeneic bone marrow transplantation (BMT), and 1 autologous BMT as consolidation therapy after CHT. In 8 cases, the presence of the t(15;17) rearrangement could be documented in diagnostic BM specimens by cytogenetic and/or molecular analysis. A two-rounds "nested" RT-PCR assay with sensitivity levels of 1 in 10(5) was used to analyze BM samples collected at 32 to 141 months from the achievement of complete remission (CR). In no cases were residual PML/RAR-alpha transcripts detectable in these remission controls. All patients are in unmaintained CR at 48 to 154 months from CR and at 6 to 17 months from PCR evaluation. These results suggest that long-term survival of APL is associated with eradication of cells carrying the specific PML/RAR-alpha rearrangement, indicating that PCR negativity should be considered the therapeutic goal in these patients. Our findings further strengthen the clinical relevance of PCR monitoring studies in APL, as opposite to other leukemic subtypes (chronic myeloid leukemia and acute myeloid leukemia-M2) in which the prognostic significance of PCR evaluation is unclear.

Adult↗
PubMed1993

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↗