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G L Castoldi

Publications and source records attributed to G L Castoldi.

At least 37 records · Page 2Linked to original sources
PubMed1994

Total loss of p53 DNA sequences in acute myeloid leukemia.

Mutations of the p53 tumour suppressor gene on chromosome 17p are a common genetic change in the malignant progression of many cancers. Here we report a case of a 71-year-old man with haematological, cytofluorimetric and cytochemical findings consistent with a 'de novo' M2 acute myeloid leukaemia (AML). A complex karyotype including a whole chromosome 17 and a t(17;?) (p11;?) was present in 8 of 10 metaphases of bone marrow cells. Southern blot analysis of the bone marrow DNA showed a specific loss of p53 gene in the AML cells. As far as we know, this is the first report of a deletion of both p53 alleles in leukaemia. The effect of the loss of p53 on the course of AML is discussed.

Aged↗
PubMed1994

Novel small deletions of the p53 gene in late-stage B-cell chronic lymphocytic leukaemia.

A group of 20 CLL patients selected for advanced clinical stage p53 mutations were analysed by single-strand conformational polymorphism (SSCP) following PCR amplification of exons 5-9. In two patients abnormal SSCP of either exon 5 or exon 8 was found and PCR products were analysed by direct sequencing. A hemizygous or homozygous 12bp deletion at codon 135 and 3bp heterozygous deletion at codon 264 were detected; also, in the latter sample a heterozygous mutation at codon 282 (Arg to Gln) was found. To our knowledge, this is the first report of p53 deletions in B-CLL. The two patients were elderly, and both had a rapidly progressive disease in the absence of unfavourable cytogenic abnormalities. These findings support a role for p53 alterations in the clinical course of some B-CLL patients.

Aged↗
PubMed1994

Neutrophils from patients with myelodysplastic syndromes: relationship between impairment of granular contents, complement receptors, functional activities and disease status.

Myelodysplastic syndromes (MDS) are stem cell disorders of clonal origin in which infections and leukemic transformation are quite frequent. Neutrophils from 28 patients with MDS were analysed by flow cytometry for the expression of the two complement receptors CR1 and CR3, the antigenic reactivity of some granule constituents--myeloperoxidase, lysozyme, elastase, lactoferrin--and functional activities, such as locomotion, respiratory burst and cytotoxicity. The results were correlated with the FAB disease subtypes, grouped as low risk (RA) and high risk patients (RAEB, RAEB-t, CMML) and with 30 healthy subjects. A significant reduction in the percentage of neutrophil CR1, CR3 positivity and chemotaxis induced by endotoxin-activated serum was detected in the high risk group when compared with the low risk group and healthy controls. Furthermore, the high risk group also showed a low amount of myeloperoxidase, elastase, lysozyme and superoxide anion, but both low and high risk groups displayed reduced cellular cytotoxicity in comparison with the control. This work indicates that MDS patients belonging to the more advanced FAB categories frequently show multiple abnormalities in the expression of neutrophil complement receptors, and granular components (> 3), as well as in cell functions, suggesting the possibility of using these phenotypic abnormalities in the monitoring of disease progression.

Chemotaxis, Leukocyte↗
PubMed1994

Acute promyelocytic leukemia: morphological aspects.

Among AML with maturation, acute promyelocytic leukemia (APL) represents a distinct subtype which accounts for 5-10% of all the FAB variants. APL may be recognized by different cytological pictures: (i) Hypergranular APL, the most typical form, showing promyelocytes with cytoplasm packed with purple granules. Most of the primary granules may be incorporated into Auer rods, sometimes stacked in bundles of faggots. (ii) Microgranular APL, characterized by fine dust-like granulation in the cytoplasm; some promyelocytes may even appear agranular by light microscopy. Most of the cells show bilobed or folded nuclei, a picture which may simulate that of acute myelomonocytic leukemia. (iii) Hyperbasophilic form, characterized by cells with high N/C ratio, and strongly basophilic cytoplasm with either sparse or no granules. Conspicuous cytoplasmatic budding is usually present, recalling the feature of micromegakaryocytes. Strong positivity for myeloperoxidase, Sudan black B and chloroacetate esterase represents the typical cytochemical pattern of M3; usually a weaker reactivity may be observed in M3v. However, sometimes a degree of cytochemical heterogeneity of APL cells may be observed, as suggested by cases displaying a strong sodium fluoride-sensitive nonspecific esterase reaction. Recently a distinct entity associated with basophilic differentiation has been described. Differential diagnosis of this form with M2-baso subtype and with cases of MDS or AML with basophilia (M2, M4 with t(6;9) translocation) may be obtained by the use of cytochemistry, cytogenetic investigations, and electron microscopy.

Carboxylic Ester Hydrolases↗
PubMed1994

Treatment of patients with acute promyelocytic leukemia. The EORTC-LCG experience. EORTC Leukemia Cooperative Group.

Acute promyelocytic leukemia (M3) is, as one of the FAB subtypes of AML, included in the EORTC/GIMEMA AML-8A and 8B randomized trials. In these trials 1519 patients were included, 477 of them in non-Italian EORTC-LCG centers and 1042 in GIMEMA centers. A total of 80 patients were classified as M3 including 18 patients with M3-variant. Thirty-nine were male and 41 female. Ages ranged from 15 to 59 years; 25 (31.3%) of them were younger than 30, 34 (42.5%) between 30 and 45, and 21 (26.3%) older than 45 years of age. 56.3% of the patients had leukocytes less than 5 x 10(9)/l at the time of diagnosis vs. 24.9% of the patients belonging to the other FAB subtypes. Remission induction consisted of a standard protocol with 3 days daunorubicin and 7 days of cytosine arabinoside. Forty-three patients (53.8%) achieved a complete remission compared to 64.6% of the remaining AML patients. After salvage treatment this percentage increased to 70%, which is the same as for the other AML subtypes. Thirteen (16.3%) patients died during remission induction, mainly due to hemorrhagic complications. This percentage is significantly higher than the death rate (9.1%) in the other FAB subtypes of AML. All patients received one course of consolidation treatment. Post consolidation treatment could be either standard maintenance, intensive consolidation courses, autologous or allogeneic transplantation, according to the guidelines of the treatment protocols. At present, relapses almost all in the bone marrow, are seen in only 34.9% of the M3 patients, compared to 48.4% in the remaining AML patients. Disease-free survival for patients less than 45 years of age with the M2 and M3 subtypes was approximately 50% at 3 years compared to 30-40% for the other FAB subtypes. Despite the higher death rate during induction, the long-term survival results were better for M3 patients in comparison with the remaining AML patients. The projected survival at 3 years was 50% for M3 patients vs. 38% for remaining patients.

Adolescent↗
PubMed1994

Acute promyelocytic leukemia: morphological aspects.

Among AML with maturation, acute promyelocytic leukemia (APL) represents a distinct subtype which accounts for 5-10% of all the FAB variants. APL may be recognized by different cytological pictures: (i) Hypergranular APL, the most typical form, showing promyelocytes with cytoplasm packed with purple granules. Most of the primary granules may be incorporated into Auer rods, sometimes stacked in bundles of faggots. (ii) Microgranular APL, characterized by fine dustlike granulation in the cytoplasm; some promyelocytes may even appear agranular by light microscopy. Most of the cells show bilobed or folded nuclei, a picture which may simulate that of acute myelomonocytic leukemia. (iii) Hyperbasophilic form, characterized by cells with high N/C ratio, and strongly basophilic cytoplasm with either sparse or no granules. Conspicuous cytoplasmatic budding is usually present, recalling the feature of micromegakaryocytes. Strong positivity for myeloperoxidase, Sudan black B and chloroacetate esterase represents the typical cytochemical pattern of M3; usually a weaker reactivity may be observed in M3v. However, sometimes a degree of cytochemical heterogeneity of APL cells may be observed, as suggested by cases displaying a strong sodium fluoride-sensitive non-specific esterase reaction. Recently a distinct entity associated with basophilic differentiation has been described. Differential diagnosis of this form with M2-baso subtype and with cases of MDS or AML with basophilia (M2, M4 with t(6;9) translocation) may be obtained by the use of cytochemistry, cytogenetic investigations, and electron microscopy.

Basophils↗
PubMed1993

Reproducibility of the morphological diagnostic criteria for acute myeloid leukemia: the GIMEMA group experience.

Diagnostic reproducibility of the FAB morphological subtypes of acute leukemia is a basic step in the assessment of the clinical outcome in multicenter trials. Unusual cytologic variables and slightly different interpretations of the FAB morphological criteria have been the most significant factors affecting the overall diagnostic concordance rate among the various centers. An evaluation of the diagnostic concurrence between 35 institutions of the Italian Cooperative Study Group GIMEMA and two reviewers of the ad hoc morphological committee has been performed on 377 patients entering the AML 8A and AML 8B GIMEMA protocols. Overall concordance rate was 62.6%. The most significant differences were observed for M2 vs M4, M4 vs M5, M1 vs M2, and M2 vs M5 subtypes. In order to minimize the impact of some diagnostic deviations on the mean cytologic concordance rate, a distinction between "major" and "minor" discrepancies in the diagnostic procedures has been proposed. When the results of the single institutions were corrected by considering the "major" discrepancies only, a mean diagnostic agreement of 78.1% was reached.

Acute Disease↗
PubMed1992

A new chromosomal breakpoint in Ph positive, bcr negative chronic myelogenous leukemia. Report of a case.

We report a new case of Ph positive chronic myeloid leukemia (CML) without the classical rearrangement in Mbcr. By Southern blot analysis the molecular breakpoint was mapped 3 to 8 kb upstream of Mbcr. This region has not been shown to be rearranged in any other described case of CML. We did not detect any specific abnormal BCR-ABL transcript even with the use of the very sensitive RNA-PCR technique.

Base Sequence↗
PubMed1991

Cytochemically unreactive neutrophils from subjects with myeloperoxidase (MPO) deficiency show a complex pattern of immunoreactivity with anti-MPO monoclonal antibodies: a flow cytometric and immunocytochemical study.

Neutrophil granulocytes from 12 subjects with primary myeloperoxidase (MPO) deficiency (six totally deficient) and 16 patients with secondary partial MPO deficiency were tested using two different anti-MPO antibodies, in combination with either a flow-cytometric technique or an immunoalkaline phosphatase staining method. Results demonstrated three different cytofluorimetric patterns of immunoreactivity with the MPO protein: (a) a bright MPO antigenic expression, typical of patients with secondary MPO deficiency (comparable to that observed in the control group); (b) a medium MPO antigenic expression, typical of subjects with primary partial MPO deficiency; and (c) a dim MPO antigenic expression, characteristic of individuals with hereditary total MPO deficiency. No significant differences in granulocyte MPO reactivity were demonstrated for the two antibodies. Furthermore, in two individuals with complete primary enzyme deficiency, the single histogram analysis of MPO fluorescence determined by flow cytometry seemed to show that only 38% (case 1) and 44% (case 2) of neutrophils were reactive with the anti-MPO antibodies: the use of multiple histogram analysis in combination with Kolmogorov-Smirnov statistics allowed us to demonstrated that all the cells express a low density of MPO antigen. These data were more or less confirmed by the APAAP labeling method, which showed a reduced straining only in subjects with primary deficiency, while all patients with secondary deficiency had scores similar to those observed in controls (healthy subjects). Compared with the immunoenzymatic technique, the flow-cytometric procedure showed a higher sensitivity to MPO, being able to estimate even minor decreases in neutrophil MPO antigenic expression, as previously postulated by other authors. This work suggests that patients with primary MPO deficiency have different amounts of MPO antigens in the neutrophil granulocytes, and the levels of MPO fluorescence seem to decline concurrently with the enzyme activity, thereby suggesting the presence of a diminished MPO production. In contrast, the normal antigenic reactivity of neutrophils from patients with acquired MPO deficiency indicates the presence of a functionally inactive form of the enzyme.

Antibodies, Monoclonal↗
PubMed1991

Should alpha interferon be used as primary treatment for hairy cell leukemia? Italian Cooperative Group for Hairy Cell Leukemia.

To answer the question of whether interferon (IFN) should replace splenectomy, we reviewed the Italian HCL Registry: the records of 450 patients with hairy cell leukemia (HCL), seen from 1975 to 1988 were analysed. Of these, 321 were considered for the study: 231 had been splenectomized, 46 of them receiving subsequently IFN and 90 patients had IFN as initial therapy. Patients treated with splenectomy showed different survival according to Jansen and Hermans' staging system, which identified two risk groups: stage 1 and stages 2 and 3, p = 0.0329. On the contrary, patients treated with IFN did not show significantly different survival according to stage. By the comparison of stage 1 patients, either treated with splenectomy or with IFN, no statistical difference in survival was registered. Different survivals emerged for patients stage 2 + 3, which improved when treated with IFN, p = 0.0324. The median failure free survival (FFS) after splenectomy resulted in 89 months versus 33 months after IFN. In conclusion, splenectomy still remains the primary therapy for HCL patients stage 1. For high risk patients, stages 2 and 3, IFN should be adopted as first line therapy, improving substantially the survival. The short duration of response to IFN suggests a sequential combination of the two treatments for this group of patients, IFN reducing tumor mass quite safely and splenectomy assuring long lasting stable disease.

Humans↗
PubMed1991

Evaluation of CR1 expression in neutrophils from chronic myeloid leukaemia: relationship between prognosis and cellular activity.

The expression of the complement receptor CR1 has been evaluated using an immunoalkaline phosphatase staining method on peripheral blood neutrophils and granulocyte precursors from 22 patients with chronic myeloid leukaemia (CML) and 15 healthy subjects. The immunocytochemical labelling pattern of CR1 was evaluated semiquantitatively on cell smears using three different anti-CR1 monoclonal antibodies. The scoring method showed that seven patients with CML had a marked reduction in CR1 expression which did not change with in vitro stimulation of neutrophils with phorbol-myristate-acetate (PMA) whereas control cells responded to PMA, increasing the receptor level two-fold. In addition, functional analysis of neutrophils with low CR1 expression from CML patients showed a very low cytolytic activity against K562 tumour target, suggesting a relationship between the cellular content of CR1 and neutrophil tumouricidal activity. The involvement of CR1 in neutrophil-mediated lysis is consistent with complete lack of tumour toxicity following receptor neutralization by anti-CR1 monoclonal antibodies. Interferon therapy improved CR1 expression and the cytolytic response of neutrophils in three out of five CML patients with a moderately low CR1 score. CML patients non-responding to interferon therapy and those with a very low CR1 score, independent of the clinical stage, progressed more rapidly into the advanced clinical stage and blastic crisis.

Complement C3b↗
PubMed1990

Prognostic subgroups in B-cell chronic lymphocytic leukemia defined by specific chromosomal abnormalities.

BACKGROUND AND METHODS: Specific chromosomal abnormalities have been shown to affect the overall survival of patients with acute leukemia, but the possibility that specific chromosomal defects may influence the course of B-cell chronic lymphocytic leukemia (CLL) is controversial. We assessed this possibility as follows: blood mononuclear cells from 433 patients with B-cell CLL in five European centers were cultured with B-cell mitogens, and banded metaphases were studied. RESULTS: Three hundred ninety-one patients could be evaluated cytogenetically, and 218 had clonal chromosomal changes. The most common abnormalities were trisomy 12 (n = 67) and structural abnormalities of chromosome 13 (n = 51; most involving the site of the retinoblastoma gene) and of chromosome 14 (n = 41). Patients with a normal karyotype had a median overall survival of more than 15 years, in contrast to 7.7 years for patients with clonal changes. Patients with single abnormalities (n = 113) did better than those with complex karyotypes (P less than 0.001). Patients with abnormalities involving chromosome 14q had poorer survival than those with aberrations of chromosome 13q (P less than 0.05). Among patients with single abnormalities, those with trisomy 12 alone had poorer survival than patients with single aberrations of chromosome 13q (P = 0.01); the latter had the same survival as those with a normal karyotype. A high percentage of cells in metaphase with chromosomal abnormalities, indicating highly proliferative leukemic cells, was associated with poor survival (P less than 0.001). Cox proportional-hazards analysis identified age, sex, the percentage of cells in metaphase with chromosomal abnormalities, and the clinical stage of the disease (Binet classification system) as independent prognostic variables. CONCLUSIONS: Chromosomal analysis provides prognostic information about overall survival in addition to that supplied by clinical data in patients with B-cell CLL.

Adult↗
PubMed1990

Chronic myelogenous leukemia with typical clinical and morphological features can be Philadelphia chromosome negative and "bcr negative".

The Philadelphia (Ph1) chromosome is found in the majority of patients affected by chronic myelogenous leukemia (CML), being considered the hallmark of the disease, but around 5-8% of patients diagnosed as CML lack the Ph1 chromosome-negative (Ph-) CML has been discussed extensively in the literature because of its heterogeneity. However, it is now accepted that some of the Ph1-CML patients have a disease indistinguishable from Ph1-positive (Ph+) CML. It was investigated whether Ph- CML with clinical and morphological features indicating true CML would always have bcr rearrangements, as the relocation of c-abl from 9q34 into the breakpoint cluster region on 22q11 is considered a crucial event in the pathogenesis of CML. From molecular studies, it seemed that Ph- CML with features of true CML always have the bcr rearrangement, while Ph- patients, lacking such rearrangement, have atypical forms of CML. Here we describe 8 Ph- CML and myeloproliferative syndrome (MPS) patients of whom 6 were by all respects true CML cases. Nevertheless, bcr rearrangement and expression of the classic bcr/abl chimeric mRNA was found in only 1 of the 6 patients. More advanced molecular techniques will be needed to understand which molecular mechanisms underlie Ph-, bcr- CML, resulting in phenotypes sometimes indistinguishable from Ph+, bcr+ CML.

Adult↗