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L Del Vecchio

Publications and source records attributed to L Del Vecchio.

At least 73 records · Page 4Linked to original sources
PubMed1992

Clinical relevance of immunological dissection in T-ALL: a report on 20 cases with stem cell (CD7+, CD4-, CD8-, CD1-) phenotype.

In a prospective study on 44 cases of T-cell origin acute lymphoblastic leukemia, 20 patients were found to display an immature immunophenotype (CD7+, CD4-, CD8-, CD1-) and were classified as T-stem cell leukemia (T-SCL). Twenty-four patients expressed CD4 and/or CD8 antigens on their blast cells, designated T acute lymphoblastic leukemia (T-ALL). The T-SCL subset showed a significantly higher median age, a more frequent incidence of extramedullary leukemia, a morphology L1 in most cases, and a poor response to treatment in terms of either complete remission rate or median survival duration. In addition, significant differences between the two groups were found in evaluating the number of days of blast disappearance from peripheral blood, of CR achievement, and of neutrophils and platelets recovery. We conclude that T-SCL represents a distinct clinical entity, characterized by a poor response to ALL conventional chemotherapy. Alternative therapeutic approaches should be developed for patients suffering from this form of leukemia, to modify its severe prognosis.

Adult↗
PubMed1992

Expression and functional role of CD54/Intercellular Adhesion Molecule-1 (ICAM-1) on human blood cells.

CD54/Intercellular Adhesion Molecule-1 (ICAM-1) is a cell adhesion molecule largely distributed among normal and neoplastic tissues. Through the binding to its ligand(s) CD54 plays a key role in cell to cell interactions leading to the immune response. Recently, CD54 expression has been investigated on hematopoietic cells: the antigen is predominantly expressed in the early stages of normal hematopoiesis and during the activation of blood cells. As regards to hematological malignancies, CD54 is strongly expressed on neoplastic cells from "stem cell derived" neoplasms. In AML, CD54 expression is related with other differentiation-linked molecules such as CD34 and HLA-DR and is significantly correlated with FAB morphological classification. In lymphoproliferative disorders, a high CD54 expression is associated with germinal centre lymphomas. This review summarizes our current understanding of CD54 with emphasis on recent advances and reference to unresolved issues such as its prognostic role in the clinical outcome of oncohematological diseases.

Antigens, CD↗
PubMed1991

Expression of myelomonocytic antigens is associated with unfavourable clinicoprognostic factors in B-cell chronic lymphocytic leukaemia.

The cross-lineage expression of five myelomonocytic antigens (CD11b, CD11c, CD13, CD14, and CD15) was analysed in neoplastic lymphocytes from 100 consecutive B-cell chronic lymphocytic leukaemia (B-CLL) patients. CD14 antigen was detected on lymphocytes from more than 50% of patients whilst smaller percentages of samples were positive for CD11b (21%), CD11c (26%), CD13 (22%), and CD15 (7%). The presence of the CD13 antigen on neoplastic lymphocytes showed a statistically significant association with the two most important unfavourable clinicoprognostic factors in B-CLL: advanced clinical stage (CD13, P less than 0.01 by the Rai staging system; P less than 0.05 by the Binet staging system) and the diffuse pattern of bone marrow infiltration (CD13, P less than 0.001). A multiple logistic regression analysis showed that the increased risk for CD13-positive patients (13.7-fold higher than CD13-negative cases; P = 0.001) of presenting a diffuse pattern of bone marrow infiltration is independent of all other prognostic factors analysed including sex, age, lymphocyte counts, and clinical stage. A statistically significant association of CD11c (P = 0.002) and CD11b (P = 0.032) expression with the pattern of bone marrow infiltration was also found. Our results indicate for the first time a statistically significant association of CD13, CD11c, and CD11b antigens with unfavourable prognostic factors in B-CLL. They suggest that the cross-lineage expression of myeloid-associated surface peptidase (CD13-aminopeptidase N) and/or cell adhesion molecules (CD11c-LeuCAMc, CD11b-LeuCAMb) may influence the biological and clinical behaviour of chronic lymphoproliferative disorders of B cells.

Age Factors↗
PubMed1990

Differential expression of CD54/intercellular adhesion molecule-1 in myeloid leukemias and in lymphoproliferative disorders.

Indirect immunofluorescence staining with monoclonal antibody (MoAb) CL203.4 of malignant cells from 269 patients with hematologic malignancies showed a heterogeneous expression of CD54/intercellular adhesion molecule-1 (ICAM-1). This marker was expressed by malignant cells of 57 out of 118 patients with myeloid malignancies and 69 out of 135 with B-lymphoid malignancies. On the other hand, CD54 was not detected on malignant cells of 16 patients with T-lymphoid malignancies. In myeloid malignancies, CD54 is preferentially expressed by "stem cell-derived" malignancies, being detectable on blast cells from almost all patients affected by chronic myelogenous leukemia in blast phase or myelodysplastic syndromes and by only 34% of patients with de novo acute myeloid leukemia (AML). The expression of CD54 did not correlate with any specific myeloid FAB subtype, although three cases of highly undifferentiated AML (FAB MO) displayed maximal levels of the antigen. The expression of CD54 in AML was significantly associated with that of CD34 and HLA-DR antigens. In B-lymphoid malignancies, CD54 expression appears to correlate with the differentiation stage of malignant cells, since B-origin acute lymphoblastic leukemias and conventional B-chronic lymphocytic leukemias (B-CLL; ie, "dim SIg" CLL) expressed lower levels of CD54 than more mature lymphoproliferative disorders ("bright SIg" CLL, prolymphocytic leukemias, and lymphoplasmacytic tumors). "High-grade" B-cell non-Hodgkin's lymphomas (B-NHL) express in general a higher level of CD54 than "low-grade" ones. This finding in conjunction with the expression of CD54 in all 17 patients with "bright SIg" CLL investigated (characterized by marked organomegaly and poor prognosis) suggest that the differential expression of CD54 in lymphoproliferative disorders may also relate to their degree of malignancy.

Antigens, Surface↗
PubMed1990

Myeloid antigen expression in adult acute lymphoblastic leukemia: clinicohematological correlations and prognostic relevance.

Fifty adult patients with acute lymphoblastic leukemia (ALL) were prospectively studied to determine the clinical and hematological relevance of surface immunophenotypes. Before treatment, blast cells were assayed for reactivity to monoclonal antibodies to B-cell, T-cell, and myeloid (My) antigens. My antigens (CD13, CD33, and VIM2, singly or in combination) were demonstrated in 16 cases (32%) along with lymphoid specificities. Bone marrow and peripheral blood stains were classified according to French-American-British (FAB) Cooperative Group criteria and evaluated for myelodysplastic changes and azurophilic granules. Mean age of My+ patients was significantly higher. Furthermore, a greater number of My+ cases showed azurophilic cytoplasmic granules and acid ANAE positivity. FAB subtypes and myelodysplastic features did not significantly differ in the two groups analyzed, but patients with myelodysplastic abnormalities represented a significantly older age group. Response to treatment was comparable in My+ and My- cases, in terms of either complete remission rate or median survival duration.

Adult↗
PubMed1989

A new combination chemotherapy for advanced chronic lymphocytic leukemia (vincristine, cyclophosphamide, melphalan, peptichemio, and prednisone protocol).

The MiNa protocol (vincristine, cyclophosphamide, melphalan, peptichemio, and prednisone) was given to 20 patients with advanced B-cell chronic lymphocytic leukemia. Complete remission (absence of all clinical and bone marrow evidence of leukemia) was obtained in 35% of cases; partial response (greater than 50% reduction in organ enlargement and decreasement of lymphocyte count to less than 15(9) X 10/l) was observed in 35% of patients. Of 12 patients (60%) previously treated with chlorambucil and corticosteroids, nine responded to treatment. Toxicity was mild and the relapse rate particularly low. It was concluded that the MiNa protocol represents an effective chemotherapy for advanced and/or progressive CLL.

Aged↗
PubMed1989

Immunodiagnosis of acute leukemia displaying ectopic antigens: proposal for a classification of promiscuous phenotypes.

The nature of the blast cells in 163 cases of acute leukemia was investigated by immunophenotyping, with particular emphasis on the expression of "ectopic" surface membrane structures. Although no antigen included in our panel except CD3 revealed absolute lineage restriction, immunological typing allowed a definite characterization of blast cells in more than 90% of cases. Four groups of patients were identified (A, B, C, D) with different degrees of antigen ectopic expression. We classified as group A leukemias (74%) those expressing conventional antigenic patterns, in absence of cross-lineage markers. Samples classified as group B (18%) showed a single ectopic membrane specificity, apparently discordant with the overall composite phenotype; such a "low-grade deviation" did not prevent a definite immunodiagnosis. Pattern C specimens (5%) revealed a promiscuous coexpression of markers related to different lineages (biphenotypic leukemias), whereas group D included unclassifiable phenotypes, characterized by no antigen or DR-only expression. Our findings suggest the possibility of interpreting complex phenotypic constellations of membrane markers in a consistent and logical manner.

Acute Disease↗
PubMed1988

The relationship of modulation of major histocompatibility complex class I antigens to retrovirus transformation in rat cell lines.

The expression of major histocompatibility complex (MHC) Class I antigens has been studied, by means of monoclonal antibodies directed against nonpolymorphic determinants of MHC Class I molecules, in two epithelial differentiated cell lines (FRTL-5 clone 2 and PC clone 3) and in one fibroblast cell line (FRT Fibro) of Fischer rat thyroid origin, before and after infection with various acute retroviruses carrying the v-ras-Ha, v-mos, v-src, polyoma middle T, and c-myc oncogenes. The results obtained indicate that a single virus does not produce identical changes in MHC Class I molecule expression in all tested lines, but a general increase occurs in lines derived from FRTL-5 clone 2 and a decrease occurs in lines derived from PC clone 3 and from FRT Fibro. Thus the modulation of expression seems to proceed always in the same direction in each cell line regardless of the infecting retrovirus and appears to involve posttranscriptional mechanisms, since no modification of expression of mRNA levels has been observed between normal and transformed cells. Only one line of PC clone 3 origin, transformed by the cooperation of two oncogenes (human c-myc and middle T), almost completely lost MHC Class I antigens on the cell surface and presented a significantly reduced synthesis of Class I mRNA.

Animals↗
PubMed1987

Expression of major histocompatibility complex class I antigens in normal and transformed rat thyroid epithelial cell lines.

Recent evidence suggests that the expression of abnormally high amounts of major histocompatibility complex (MHC) class I molecules may be a feature of at least some kinds of transformed cells. To investigate this aspect of neoplastic transformation we studied the expression of MHC class I antigens in an experimental model of normal, tumor-derived, and virus-transformed thyroid epithelial cell lines. The expression of MHC class I antigens has been studied by means of several monoclonal antibodies directed against either monomorphic or polymorphic epitopes and quantified by flow cytometry. Class I specific mRNA transcripts have been also analyzed by Northern blot hybridization, using a mouse genomic H-2 DNA probe. Our results indicate a modulation of MHC class I expression associated with loss of the differentiated phenotype and with transformation of thyroid epithelial cell lines. Undifferentiated cells in fact show a small quantity of these antigens, because acquisition of a fully differentiated phenotype is associated with an increase in their expression. Cell lines derived from thyroid tumors show reduced expression of MHC class I antigens, as compared to differentiated cells. Conversely, cells transformed in vitro by a retrovirus carrying the v-raski oncogene exhibit an increase in these antigens in comparison to their normal differentiated counterparts. Cells infected with a mutant virus able to transform cells only at the permissive temperature of 33 degrees C show a similar increased expression. After a shift to the nonpermissive temperature of 39 degrees C, infected cells, even those losing the transformed phenotype retain the same increased amount of MHC class I antigens. Our data suggest that the modulation of MHC class I antigen expression is strongly associated with transformation in thyroid epithelial cells.

Adenocarcinoma↗
PubMed1987

c-fos oncogene expression in human hematopoietic malignancies is restricted to acute leukemias with monocytic phenotype and to subsets of B cell leukemias.

To evaluate relationships between c-fos proto-oncogene expression and specific lineages of hematopoietic differentiation we analyzed the constitutive and TPA-induced expression of the c-fos gene in a wide variety of fresh human leukemic cells. High constitutive c-fos expression was detected in acute leukemias with monocytic phenotype (FAB M4/M5) and in subsets of B lymphoid leukemias, some of which coexpressed B lymphocytic and monocytic markers. Conversely, low basal levels of c-fos transcripts were found in pure acute granulocytic leukemias (FAB M1/M2/M3), in erythroleukemias (FAB M6), in the great majority of B, and in all T lymphoid leukemias. TPA-induced c-fos expression seems to correlate with monocytoid differentiation only when sustained levels of transcripts (ie, detectable for at least 24 hours) were detected. Sustained c-fos expression was in fact observed only in those myeloid or lymphoid cells that acquired a stable monocyte-like phenotype in response to the phorbol ester. These results indicate that high constitutive c-fos expression may identify myelomonocytic-oriented forms of leukemia, specific subsets of B lymphoid malignancies, and at least some cells terminally differentiated in vitro to a monocyte-like phenotype. c-fos oncogene expression can therefore be regarded as an additional marker for the subclassification of human leukemias.

Acute Disease↗
PubMed1985

HLA and prognostic factors in primary breast cancer.

A group of 157 women with primary breast cancer (BC) were typed for HLA antigens, and gene frequencies were compared to those of 327 control healthy individuals. Diagnosis of BC was made for all patients on surgical mastectomy specimens; histologic grading, estrogen (ER) and progesterone (PgR) receptors were determined on all primary tumors. Typed antigens included the majority of the specificities controlled by the HLA-A, -B and -C loci, according to the 8th International Histocompatibility Testing Workshop recommendations. No significant discrepancy in their frequencies was found in the undivided sample as compared to controls. The analysis of HLA gene frequency was extended to subsets of patients identified by the following prognostic features: (a) age at tumor diagnosis (pre-menopause vs. post-menopause); (b) receptor status (presence vs. absence of ER and PgR); (c) mammary gland dysplasia (presence vs. absence); (d) histologic grade (grade 3 vs. grades 1 and 2 combined); (e) time to relapse before or after 24 months following mastectomy). A moderate deviation from normal of some genes was found in several subsets, often affecting only one of the antithetical subgroups (feature present vs. feature absent). In the instance of B5, the increase in frequency of the gene in one of the subset pair (ER + subjects) was balanced by a decrease of the same gene in the counterpart (ER-subjects). Increased frequencies were found for the B7 gene in the following prognostic groups: (a) lack of ER (0.08); (b) lack of PgR (0.09); (c) absence of mammary dysplasia (0.075); (d) histologic grade 3 (0.10); and (e) premenopause (0.12), the last two showing significant divergence from normal. When features (d) and (e) on the one hand and (a), (b), (d) and (e) on the other were combined, B7 reached frequencies of 0.18 (p less than 5 X 10(-4] and of 0.29 (p less than 5 X 10(-6], respectively.

Adult↗
PubMed1985

Monoclonal antibodies to the L1210 murine leukemia cell line and to a drug-altered subline.

A panel of murine monoclonal antibodies (MAbs) was produced by fusing NS-0 myeloma cells with spleen cells of a BALB/c X DBA/2 F1 mouse hyperimmunized against a highly immunogenic subline of the L1210 leukemia obtained by in vivo treatment of the L1210 parental line with the antitumor drug 5-(3,3'-dimethyl-1-triazeno)imidazole-4-carboxamide (DTIC). Among the 52 MAbs produced 16 (anti-D) were specifically cytotoxic in a complement-dependent cytotoxicity assay for the drug-altered subline and the others (anti-L) also cross-reacted with the L1210 parental leukemia. Six anti-D and three anti-L MAbs were selected for detailed studies of tissue specificity. In quantitative absorption experiments the antigens defined by these antibodies could not be detected on cells from normal mouse tissues (lung, liver, kidney, heart, spleen, and thymus). The reactivities of both anti-D and anti-L MAbs against a panel of L1210/DTIC sublines obtained at different times were assayed. The results showed that the antigenic specificities defined by anti-L MAbs were expressed on almost every L1210/DTIC subline while the anti-D MAbs detected antigenic structures specific for the L1210/DTIC used for the immunization. None of the MAbs tested cross-reacted with the L5178Y lymphoma or with its DTIC-altered sublines. The failure of anti-D MAbs to cross-react with cells from other L1210/DTIC sublines supports the hypothesis that the immunological alterations induced by the DTIC treatment are the consequence of mutagenic activity of the drug. On the other hand the presence of anti-L antigens on the cells of every L1210 subline indicates that the DTIC alteration is not accompanied by a loss of the tumor-associated antigen from the L1210 leukemia.

Animals↗