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N Testoni

Publications and source records attributed to N Testoni.

At least 73 records · Page 4Linked to original sources

FLAG (fludarabine+cytosine arabinoside+G-CSF) induces complete remission in acute-phase chronic myeloid leukaemia: a case report.

The adenine nucleoside analogue fludarabine phosphate in combination with cytosine-arabinoside (Ara-C) and granulocyte-colony stimulating factor (G-CSF) has recently proved effective in the treatment of poor-prognosis acute non-lymphoid leukaemia. We used this triple combination in a case of Ph1+ chronic myeloid leukaemia (CML) unresponsive to alpha interferon that had progressed to acute phase after 5 months of treatment with 6-mercaptopurine plus hydroxyurea. The patient was treated with four courses of fludarabine 30 mg/m2 + Ara-C 2 g/m2 (days 1-5) and G-CSF (from day 0 to polymorphonuclear (PMN) recovery). Bone marrow blasts decreased from 80% to less than 5%, and karyotyping showed a progressive clearance of Ph1+ metaphases (from 100% to 9% after the fourth course). The patient is presently receiving autologous bone marrow transplantation (ABMT). This therapeutic success in a patient for whom conventional treatment would usually be ineffective makes this combination worthy of further studies, in view of its wider use as a preparative regimen to ABMT in CML.

Adult↗

Increased expression of myeloid antigen markers in adult acute lymphoblastic leukaemia patients: diagnostic and prognostic implications.

By applying direct immunofluorescence with a dual-staining technique we were able to demonstrate that 20/37 (54%) patients with acute lymphoblastic leukemia (ALL) expressed both lymphoid and myeloid antigens on the same leukaemic cells. CD13 and CD33 myeloid antigens were detected in 18/20 and in 15/20 cases respectively, and both in 13. Molecular studies confirmed that the four patients with T-cell phenotype had molecular rearrangement of T-cell receptor (TcR) beta chain, and 26 ALL patients with 'B-cell' phenotype showed JH rearrangement. Two ALL patients without (ALL/My-) and three with myeloid antigens (ALL/My+) also demonstrated bcr/abl rearrangement. Both groups of patients had similar presenting features such as age, sex, Hb level, white blood cells, platelet counts and cytogenetic features. Complete response was achieved in 16/17 (94%) ALL/My- patients and in 15/18 (83%) ALL/My+ patients (two deaths occurred during induction) with a mean duration of 17 and 16 months respectively and with similar survival and event-free survival curves. Myeloid antigen expression in adult ALL patients may occur more frequently than previously reported. The presence of myeloid antigen does not identify, in our series, a higher-risk subgroup of patients, although lack of any statistical evidence of prognostic significance needs to be confirmed in a larger case study.

Adolescent↗

FLAG (fludarabine + high-dose cytarabine + G-CSF): an effective and tolerable protocol for the treatment of 'poor risk' acute myeloid leukemias.

Twenty-eight patients with poor prognosis acute myeloid leukemia (AML) received therapy with two courses of fludarabine 30 mg/m2/day + ara-C 2 g/m2/day (days 1-5) and G-CSF 5 mg/kg/day (FLAG) (from day 0 to polymorphonuclear recovery). Eighteen patients were considered 'refractory' (eight primarily resistant, five relapsing within 6 months of initial remission, or at a second relapse; five relapsing after an autologous bone marrow transplantation procedure. Ten cases were defined 'secondary' AML (diagnosis of AML made after a preexisting diagnosis of: myelodysplastic syndrome: five cases; myelodysplastic syndrome after therapy for breast cancer: one case; previously untreated, and concomitant, non-Hodgkin's lymphoma: two cases; Hodgkin's disease treated with chemoradiotherapy: one case). Overall, 15 patients (58%) achieved a complete remission (CR). Two patients died of infection during induction, and 11 had resistant disease. Analyzing the data in relation to selected host and disease characteristics, the response varied widely. The highest CR rates (89%) were obtained in secondary AML; in particular, two cases of 'second-primary' (concomitant with low-grade non-Hodgkin's lymphoma) AML obtained CR for both diseases. Refractory AML differed widely for response: high CR rate (75%), although with short mean CR duration for primary resistance AML, and very poor response (11% CR) for relapsed (early, second, after ABMT) cases. Interestingly, a slow kinetic of leukemic growth in vivo before FLAG administration was significantly related to the response and outcome (p = 0.0002). Hematological and nonhematological toxicities were acceptable. In conclusion, the FLAG regimen has significant antileukemic activity and acceptable toxicity especially in secondary AML, both with and without coexisting lymphoid malignancy.

Acute Disease↗

t(8;14)(q11;q32) in acute lymphoid leukemia: description of two cases.

An 8;14 chromosome translocation with breakpoints at q11 and q32, respectively, is described as the sole abnormality in bone marrow cells of two adult patients with common acute lymphoblastic leukemia (ALL). The Southern blot analysis revealed a rearrangement after BamHI and HindIII digestion and hybridization with a JH probe, thus demonstrating the involvement of the gene coding for the heavy chains of the immunoglobulins (IgH). Therefore, a pathogenetic mechanism similar to that observed in Burkitt's lymphoma and its variants, or in other lymphomas with t(11;14) or t(14;18), may be hypothesized. In all these cases IgH is juxtaposed to an oncogene (c-MYC, BCL-1, and BCL-2, respectively). A similar structure, with oncogene type potential, could be present on 8q11. The patients underwent a complete remission after induction therapy.

Adult↗

The type of BCR/ABL junction does not predict the survival of patients with Ph1-positive chronic myeloid leukaemia.

The prognostic value of the location of the breakpoint on chromosome 22 in patients with Ph1+ chronic myeloid leukaemia (CML) is still controversial. We analysed both DNA rearrangement and transcript type in a new continuous series of CML patients. By Southern blotting analysis, we found that, out of 72 patients, 43 had a 5' rearrangement and 29 a 3' one, of the 43 5'-rearranged patients, 35 carried an a2b2 transcript and eight an a2b3 one, while, of the 29 patients rearranged in the 3' part of the M-BCR area, 26 had an a2b3 transcript, one had an a2b2 transcript and two carried both types of transcript. Thus, mRNA studies allow to detect an a2b3 transcript in 17.7% of 5' rearranged patients. However, no correlation was observed between type of transcript and survival, as after DNA studies.

Adolescent↗

Structural organization of BCR-ABL gene in chronic phase and blast transformation in chronic myeloid leukemia patients.

We studied 36 DNA samples of 18 patients affected with chronic myeloid leukemia (CML) for the presence of mutations in the first exon of the BCR gene was divided into four regions amplified by polymerase chain reaction (PCR). By single strand conformation polymorphism analysis (SSCP) and direct sequencing of amplified fragments, we found different banding profiles in 9 out of 18 patients in the PCR fragment spanning nucleotide 506-826. In one patient, sequence analysis revealed the presence of a point mutation at nucleotide 669 (A-T; Gln-Leu). No difference was found between DNA samples collected during the chronic phase and the blastic transformation. No different mobility shifts of single stranded PCR products were found in the other amplified fragments. The activation of BCR-ABL involves direct interaction between BCR first exon sequences and the tyrosine kinase regulatory domains of ABL. In the first BCR exon, and around the mutated sequences two SH-2-binding sites, are retained. These domains are essential for BCR-ABL-mediated transformation. Our results demonstrate the presence of point mutation in this regulatory region, which may suggest a role for the altered BCR sequence in activation of the BCR-ABL oncogene.

Base Sequence↗

In vitro amplification of hypervariable DNA regions for the evaluation of chimerism after allogeneic BMT.

The role of mixed hematopoietic chimerism in engraftment and relapse after allogeneic BMT remains unclear. To better evaluate post-transplant chimerism we used polymerase chain reaction (PCR) in vitro amplification of four single locus simple repetitive DNA sequences, all of which vary extensively in their repeat number among different individuals: variable number of tandem repeats D1S80, APOB and D17S5, and the tetranucleotide repeat F8VWF. We tested 13 cases of CML, four of multiple myeloma (MM), three of ANLL and one of B-CLL. In a sequential analysis protocol with the different loci, the donor could be distinguished from the recipient in 14 of 20 (70%) pairs with the first marker used (D1S80). When a donor of opposite sex was involved, karyotyping and Y chromosome-specific PCR were also used. With the use of the four markers, chimerism was identified in all the pairs. Mixed chimerism was present in 5 patients, and complete chimerism in 15. No patients relapsed. The application of PCR for documenting post-transplant chimerism has several advantages over Southern blotting: increased sensitivity, use of small amounts of sample, ease of preparation of DNA, elimination of restriction enzyme analysis and of radioisotopes, and speed.

Adult↗

New strategies for selection of unrelated bone marrow donors.

An important problem in the selection of unrelated donors for bone marrow transplantation (UD-BMT), is HLA matching, between selected donor and recipient. Serological screening, mixed lymphocyte culture (MLC), and sequence specific oligonucleotide genotyping (PCR-SSO) are the methods commonly used for typing of HLA-genes. These ways to select donor candidates are time-expensive. We set up new applications of the "fingerprinting-PCR" technique, to analyse the polymorphic second exon of DRB, DQB, DQA, DPB of HLA Class II and second exon A, B, C HLA-Class I genes, and to search for identity between patient and serologically selected unrelated donors. In an assessment of the technique, 50 normal samples, and 4 unrelated HLA-A and HLA-B serological matched patient-donor pairs were analysed for HLA polymorphic regions. In 3 of the 4 cases (UD-BMT) at least HLA-DRB mismatched different donor-transplanted patterns were identified. In all cases PCR-SSO analysis was performed as control. Based on our data, we suggest that identification of UD for allogeneic BMT should follow these steps: 1) serological HLA-Class I and II genes screening; 2) HLA-Class II DRB gene PCR fingerprinting; 3) confirmation by SSO analysis in case of fingerprinting identity. 4) HLA-Class II DQA, DQB, DPB PCR fingerprinting. Moreover, confirmation by PCR fingerprinting or protein isoelectrofocusing of HLA-Class I identity is recommended. This "strategy" may contribute to rapid and specific selection of unrelated marrow donors.

Base Sequence↗

Minimal residual disease status in transplanted chronic myelogenous leukemia patients: low incidence of polymerase chain reaction positive cases among 48 long disease-free subjects who received unmanipulated allogeneic bone marrow transplants.

Forty-eight long-term disease-free chronic myelogenous leukemia (CML) patients, who had received unmanipulated allogeneic bone marrow transplants (BMT) for eradication of the Philadelphia (Ph1)-positive clone were studied by polymerase chain reaction (PCR), using a very sensitive PCR procedure and very stringent criteria for preventing and revealing contamination. Nine patients (18%) were positive at the first PCR examination, but only one patient remained PCR positive four years after. However, a second PCR analysis performed on new bone marrow samples obtained at a median interval of 14 months (range 6-16) after the first specimen collection from six of nine originally positive cases, and from 16 of 39 originally negative cases, showed that only one of the six positive cases remained positive, whereas negativity was confirmed in all the originally negative patients. These data are evidence that the Ph1-positive clone is apparently completely eradicated in the majority of CML patients who survive disease-free long-term after an unmanipulated allogeneic BMT and that only sporadic cases remain PCR-positive four years post-BMT. The data also show that at least two sequential bone marrow samples for each patient must be analyzed before drawing conclusions regarding the stable persistence of BCR/ABL transcripts and the minimal residual disease status.

Adolescent↗

Cytogenetic events after bone marrow transplantation for Philadelphia chromosome positive chronic myeloid leukemia.

Allogeneic bone marrow transplantation is the only way to cure patients with Ph1+ chronic myeloid leukemia. It is commonly assumed that, in order to obtain a cure for the patients, the leukemic clone must be completely destroyed by the conditioning treatment and the donor's bone marrow must repopulate the hemopoietic niches leading to a "complete chimera". However, cytogenetic analyses, supported by molecular ones, indicate that Ph1+ cells, far from being completely destroyed by chemo-radiotherapy may persist for a long time, probably in the majority of the patients. As demonstrated by the outcome of patients receiving T-cell depleted marrow, immune mechanisms must be involved in controlling and progressively reducing the size of the residual leukemic clone. Furthermore, immunodulating therapeutic strategies, represented by cyclosporin-A discontinuation or alpha interferon treatment, may successfully reduce the Ph1+ cell population even after a full relapse.

Bone Marrow Transplantation↗

Molecular and cytogenetic studies of a patient with Philadelphia-negative, BCR-positive chronic myeloid leukemia and t(12;12)(q13;p12).

A patient with Philadelphia (Ph1)-negative, breakpoint cluster region (bcr)-positive chronic myeloid leukemia (CML) is reported. Pulsed-field gel electrophoretic analysis demonstrated the comigration of both ABL and BCR sequences on the same BssHII and SacII fragment. Moreover, in situ hybridization studies demonstrated that ABL sequences had been moved from band 9q34 to 22q11 and that the additional t(12;12)(q13;p12) was not involved in the ABUBCR related translocation. Nevertheless, a possible role of oncogenes or regulatory sequences activated or inhibited by the additional translocation cannot be excluded.

Adult↗

Cytogenetic and molecular studies in patients with chronic myeloid leukemia and variant Philadelphia translocations.

Out of 105 Philadelphia (Ph) positive chronic myeloid leukemia patients analyzed, six (5.7%) carried a variant Ph translocation, namely t(6;9;9;10;22)(q24;p13;q34;p15;q11); t(9;13;22)(q34;q21;q11);der(2)(2pter----2q31::9q21---- 9q34::22q11----22qter) and der(9)t(2;9) (9pter----9q21::2q31----2qter);t(7;9;22)(q11;q34 ;q11), 14q + ;t(7;9;22)(q35;q34;q11), and t(9;11;22) (q34;q13;q11), respectively. Five of these patients were analyzed with Southern blotting. Three of them showed an atypical molecular pattern; namely, the patient with t(9;13;22) showed no rearrangement in the breakpoint cluster region (bcr), the patient with t(7;9;22)(q35;q34;q11) showed a 3' deletion, and the patient with t(7;9;22), 14q + showed a bcr rearrangement 3' to the exon 4 of the M-BCR. Chromosome in situ hybridization studies demonstrated that in patient one, a two-step translocation occurred: the first step moved the 3' bcr from chromosome 22 to chromosome 9, and the second moved the terminal part of 22q, carrying the c-sis protooncogene, to 10p. Variant Ph translocations appear to be associated with atypical molecular breakpoints.

Chromosome Banding↗