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Biomedical subjects

B E Leone

Publications and source records attributed to B E Leone.

At least 19 recordsLinked to original sources
PubMed2003

Prediction of nodal spread of breast cancer by using artificial neural network-based analyses of S100A4, nm23 and steroid receptor expression.

The expression of tumour promoter gene S100A4, metastasis suppressor gene nm23, oestrogen and progesterone receptors, and tumour grade and size have been investigated for their potential to predict breast cancer progression. The molecular and cellular data have been analysed using artificial neural networks to determine the potential of these markers to predict the presence of metastatic tumour in the regional lymph nodes. This study shows that tumour grade and size are poor predictors. The relative expression of S100A4 and nm23 genes is the single most effective predictor of nodal status. Inclusion of oestrogen- and progesterone-receptor status with tumour grade and size markers improves prediction; however, there may be some overlap between steroid receptors and molecular markers. This study also underscores the power of artificial neural network techniques to predict the potential of primary breast cancers to spread to axillary lymph nodes. This could aid the clinician in determining whether invasive procedures of axially node dissection can be obviated and whether conservative forms of treatment might be appropriate in the management of the patient.

Adult↗
PubMed2000

Vitamin D3 affects differentiation, maturation, and function of human monocyte-derived dendritic cells.

We studied the effects of 1alpha,25-dihydroxyvitamin D3 (1alpha, 25-(OH)2D3) on differentiation, maturation, and functions of dendritic cells (DC) differentiated from human monocytes in vitro in the presence of GM-CSF and IL-4 for 7 days. Recovery and morphology were not affected by 1alpha,25-(OH)2D3 up to 100 nM. DC differentiated in the presence of 10 nM 1alpha,25-(OH)2D3 (D3-DC) showed a marked decrease in the expression of CD1a, while CD14 remained elevated. Mannose receptor and CD32 were significantly increased, and this correlated with an enhancement of endocytic activity. Costimulatory molecules such as CD40 and CD86 were slightly decreased or nonsignificantly affected (CD80 and MHC II). However, after induction of DC maturation with LPS or incubation with CD40 ligand-transfected cells, D3-DC showed marginal increases in MHC I, MHC II, CD80, CD86, CD40, and CD83. The accessory cell function of D3-DC in classical MLR was also inhibited. Moreover, allogeneic T cells stimulated with D3-DC were poor responders in a second MLR to untreated DC from the same or an unrelated donor, thus indicating the onset of a nonspecific hyporesponsivity. In conclusion, our data suggest that 1alpha,25-(OH)2D3 may modulate the immune system, acting at the very first step of the immune response through the inhibition of DC differentiation and maturation into potent APC.

Adjuvants, Immunologic↗
PubMed2000

Engagement of the leukocyte-associated Ig-like receptor-1 induces programmed cell death and prevents NF-kappaB nuclear translocation in human myeloid leukemias.

Leukocyte-associated Ig-like receptor-1 (LAIR-1) is a surface molecule that functions as an inhibitory receptor on natural killer cells, T lymphocytes and monocytes. Here, we provide evidence that occupancy of LAIR-1 on human myelomonocytic leukemic cell lines inhibits proliferation and leads to programmed cell death (PCD), evaluated by propidium iodide staining and transmission electron microscopy. Interestingly, PCD elicited via LAIR-1 was not blocked by different caspase inhibitors, at variance with apoptosis induced via CD95/Fas, which was prevented by the caspase-1 and caspase-8 specific inhibitors. In addition, we show that the p65 subunit of the nuclear factor kappaB (NF-kappaB), constitutively expressed in the nucleus of these cell lines, was retained in the cytoplasm upon engagement of LAIR-1. This was evident already 8 h after LAIR-1 occupancy, when apoptosis was not yet detectable by fluorometric or ultrastructural analysis. Moreover, a reduction in inhibitor kappaBalpha phosphorylation was observed after LAIR-1 engagement. As blocking of NF-kappaB activation has been shown to rescue sensitivity to anti-cancer drugs in solid tumors, we suggest that LAIR-1 may represent a possible target for pharmacological approaches aimed to potentiate anti-leukemic therapy.

Active Transport, Cell Nucleus↗
PubMed2000

Factors affecting survival and long-term outcome in the cirrhotic patient undergoing hepatic resection for hepatocellular carcinoma.

AIMS: Prognostic analysis of hepatocellular carcinoma (HCC) in the cirrhotic patient undergoing hepatic resection is necessary in order to determine the clinical effect of hepatectomy on prognosis. PATIENTS AND METHODS: Univariate and multivariate retrospective analyses were performed in 51 cirrhotic patients (38 men, 13 women; mean age 65 years, range 43-81 years) with supervening HCC undergoing hepatic resection between January 1993 and December 1997. RESULTS: Segmental liver resection was performed in 39 patients (76%) with non-anatomical (wedge) resections in the remainder of cases. The post-operative mortality rate was 8%. The tumours recurred in 23 patients (45%), with 12 patients (52% of recurrences) recurring within 1 year of surgery and 22 patients (96% of recurrences) within 3 years. Recurrent disease was most frequently intrahepatic (22 patients). Significant risk factors for recurrence were micro/macro vascular invasion, and symptoms. CONCLUSIONS: The recurrence rate of hepatocellular carcinoma in patients with cirrhosis undergoing surgical resection alone is high and actuarial survival at 4 years is low. Other approaches to the treatment of hepatocellular carcinoma in patients with cirrhosis require consideration.

Actuarial Analysis↗
PubMed1999

Effects of cryopreservation on in vitro and in vivo long-term function of human islets.

BACKGROUND: The possibility of performing transplantation several days after explant seems to be a peculiarity of islet grafts, and the opportunity to cryopreserve human islets may permit an indefinite period for modulating the recipient immune system. The aim of the present study was the evaluation of in vitro and in vivo functional properties of cryopreserved human islets. METHODS: We used six consecutive human islet preparations not suitable for an immediate transplantation in diabetic patients because the limited islet mass separated. The in vitro function of cryo and fresh islets was studied by determination of insulin and glucagon secretion in response to such classical stimuli as glucose (16.7 mM), glucose (16.7 mM) + 3-isobutyl-1-methylxanthine (0.1 mM), arginine (10 mM), and tolbutamide (100 microM). In vivo islet function was assessed through intravenous glucose tolerance tests performed at 15, 30, 60, and 90 days after transplantation of 1000 hand-picked fresh or cryopreserved islets in nude mice. RESULTS: Basal secretion of true insulin was significantly higher in cryopreserved islets than in fresh ones. The response of cryopreserved islets to arginine and glucose + isobutyl-1-methylxanthine seemed partially impaired. Proinsulin-like molecule secretion seemed higher in cryopreserved than in fresh islets in response to all secretagogues used, and the difference was statistically significant for arginine. The capacity of human cryopreserved islets to maintain a correct metabolic control in diabetic nude mice was progressively lost in 3 months. CONCLUSIONS: These findings showed that cryopreservation affects the function of isolated human islets, maintaining in vivo function for a limited period of time.

1-Methyl-3-isobutylxanthine↗
PubMed1999

Glucocorticoids affect human dendritic cell differentiation and maturation.

Because dendritic cells (DC) play a major role in the initiation of T cell-mediated immunity, we studied the effects of glucocorticoids, well-known inhibitors of the immune and inflammatory response, on the differentiation and maturation of human DC. DC were differentiated from human monocytes by culture with GM-CSF and IL-4 for 7 days with and without dexamethasone (Dex). Cells treated with Dex (10-8 M) (Dex-DC) developed a characteristic dendritic morphology; however, membrane phenotype analysis demonstrated that they were not fully differentiated. Dex-DC expressed low levels of CD1a and, unlike untreated cells, high levels of CD14 and CD16. Molecules involved in Ag presentation (CD40, CD86, CD54) were also impaired. In contrast, molecules involved in Ag uptake (mannose receptor, CD32) and cell adhesion (CD11/CD18, CD54) were up-regulated. After exposure to TNF-alpha or CD40 ligand, Dex-DC expressed lower levels of CD83 and CD86 than untreated cells. Dex-DC showed a higher endocytic activity, a lower APC function, and a lower capacity to secrete cytokines than untreated cells. Overall, these results indicate that DC differentiated in the presence of Dex are at a more immature stage. Moreover, Dex also partially blocked terminal maturation of already differentiated DC. In conclusion, our data suggest that glucocorticoids may act at the very first step of the immune response by modulating DC differentiation, maturation, and function.

Antigen Presentation↗
PubMed1999

Human proinsulin production in primary rat hepatocytes after retroviral vector gene transfer.

The development of autologous somatic cells, engineered for the synthesis and release of human insulin under physiological stimuli, would certainly represent a major breakthrough in the therapy of insulin-dependent diabetes mellitus. We generated a retroviral vector containing the human proinsulin cDNA and the gene coding for the human nerve growth factor receptor for quantitative analysis of transduced cells. Primary rat hepatocytes were selected as target cells because of the constitutive expression of the pancreatic beta-cell glucose transporter GLUT-2 and the glycolitic enzyme glucokinase. Appropriate conditions for culture and retroviral transduction are described. The highest transduction efficiency, evaluated as percentage of LNGFr expressing cells was obtained by repeated infection cycles (40+/-10%). Human proinsulin accumulated in the culture medium of transduced rat hepatocytes (mean+/-SD): 18.1+/-7.9 (range 8.7-36.4) ng/24h/10(6) cells. Primary rat hepatocytes can be efficiently transduced by a retroviral vector and the de novo synthesis of human proinsulin can be induced. Primary cultured hepatocytes represent an useful model to test retroviral constructs engineered for the glucose-inducible expression of insulin under the control of liver-specific promoters.

Animals↗
PubMed1999

Glucocorticoids increase the endocytic activity of human dendritic cells.

We have investigated the effect of glucocorticoids (GC) on antigen uptake molecule expression and on endocytic activity of human dendritic cells (DC). Human monocyte-derived DC were differentiated in vitro for 7 days with granulocyte macrophage colony stimulating factor and IL-4 in the presence or absence of dexamethasone 10(-8) M (Dex). Dex-treated DC showed an enhancement of mannose receptor (MR)-mediated endocytosis (measured as uptake of FITC-dextran) and of fluid-phase endocytosis [measured as uptake of Lucifer yellow (LY)] The effect was dose dependent and correlated with the length of exposure to Dex. The expression of receptors involved in antigen capture was investigated by FACS analysis. Dex up-regulates MR, CD16 and CD32 expression on DC. After maturation with tumor necrosis factor-alpha or CD40 ligand in Dex-treated DC, despite a reduction induced by maturation the endocytic activity of FITC-dextran and LY, the expression of MR, CD16 and CD32 remained higher than in control DC. In view of the fact that antigen capture was increased in cells cultured with Dex, we evaluated the ability to present soluble antigen that needs to be taken up and processed. Cells differentiated in the presence of Dex showed much lower efficiency in presenting tetanus toxin to specific autologous T cell lines. In conclusion our data suggest a new mechanism by which GC may influence immune responses. In fact with the increase in endocytic activity, Dex favors the scavenging of antigen from the external milieu, decreasing antigen concentration and availability, and simultaneously inhibiting the capacity to stimulate T cells.

Antigen Presentation↗
PubMed1999

[Hemangiopericytoma-like tumor (HPCLT) of the nasal cavity: morphological, immunohistochemical, and ultrastructural features].

A case of hemangiopericytoma-like tumour (HPCLT) of the nasal cavity is described in a 81-year-old woman. The tumour, accompanied by symptoms of nasal obstruction and epistaxis, presented as a polypoid lesion filling the left middle meatus region. Histological, immunohistochemical and electron microscope studies revealed a uniform sheet-like proliferation of spindle to oval vimentin-positive cells growing around a rich vascular network. The favourable outcome sixteen months after endoscopic sphenoethmoidectomy would seem to confirm the diagnosis of HPCLT. The differential diagnosis of this rare lesion is discussed.

Aged↗
PubMed1998

CD14+ CD34+ peripheral blood mononuclear cells migrate across endothelium and give rise to immunostimulatory dendritic cells.

We describe a subset of peripheral CD14+ cells, coexpressing the CD34 progenitor marker and able to migrate across endothelial cell monolayers. On culture with granulocyte-macrophage-CSF, this population differentiated into dendritic cells expressing CD83, CD80, HLA-DR(bright), CD86, and CD54. These dendritic cells were immunostimulatory, in that they induced proliferation of allogenic and tetanus toxoid-specific T lymphocytes. The CD14+ CD34+ population expressed higher levels of platelet endothelial cell adhesion molecule-1 (PECAM-1) and alpha4beta1 integrin than the CD14+ CD34- counterpart, being dull positive for other integrins. Using stably transfected PECAM-1+, VCAM-1+, or ICAM-1+ cells, we found that PECAM-1 and, to a lesser extent, VCAM-1, could support transmigration of CD14+ CD34+ cells, whereas the alphaL-ICAM-1 interaction was involved in cell adhesion. PECAM-1-driven transmigration was conceivably dependent on a haptotactic gradient, as it was reduced by 80% across NIH3T3 cells transfected with the PECAM-1-delta cyto deletion mutant. This mutant lacks the cytoplasmic tail and displays a reduced tendency to localize at the intercellular junctions, thus failing to form a molecular junctional gradient. Once differentiated, dendritic cells derived from CD14+ CD34+ precursors retained their transendothelial migratory capability, using both PECAM-1 and ICAM-1 for transmigration. We suggest that a subset of CD14+ CD34+ circulating leukocytes can localize to peripheral tissues and differentiate into functional dendritic cells, thus representing a functional reservoir of potential APC. PECAM-1, constitutively expressed on vascular endothelium, is likely to play a relevant role in the egress of this population from the bloodstream.

Antigens, CD34↗
PubMed1998

Expression of metastasis-associated genes h-mts1 (S100A4) and nm23 in carcinoma of breast is related to disease progression.

The murine 18A2/mts1 and its human homolog h-mts1 (S100A4), encoding a Ca2+-binding protein belonging to the S-100 family, are associated with high invasive and metastatic potentials of murine tumors, human tumor cell lines in vitro, and human tumors growing as xenografts. The nm23 is a putative metastasis-suppressor gene whose expression has been found to correlate inversely with the metastatic potential of some forms of human cancer. The products of both human genes alter cytoskeletal dynamics, with antagonistic effects. In view of the equivocal association of nm23 with the metastatic potential of human cancer, we suspected that the relative expression of h-mts1 and nm23 might reflect tumor progression more accurately than either of them alone. We describe here the expression of these genes in infiltrating ductal carcinomas of the breast and show that high h-mts1 expression is associated with metastatic spread to the regional lymph nodes. The expression of nm23 on its own did not show a statistically significant inverse correlation with nodal spread. However, the expression status of the two genes, taken together, correlated strongly with the occurrence of nodal metastases. Breast cancers with no detectable expression of h-mts1 were found to be estrogen and progesterone receptor positive. Expression of h-mts1 was not related to tumor differentiation. The clinical data, together with the state of expression of steroid receptors and the expression levels of h-mts1 and nm23 genes, were analyzed using artificial neural networks for accuracy in predicting nodal spread of the carcinomas. These analyses support the conclusion that, overall, h-mts1 expression appears to be associated with and indicative of more aggressive disease. Complemented with nm23, h-mts1 could provide a powerful marker of breast cancer prognosis.

Adult↗
PubMed1998

Clinical presentation, diagnosis and survival of resected distal bile duct cancer.

The aim of the study was the definition of the clinical features and survival of 27 resected cases of distal bile duct carcinoma. This neoplasm accounted for 14% of all periampullary malignancies treated by pancreaticoduodenectomy between 1990 and 1996. Jaundice was present in 96% of patients, but was the first symptom only in 78%. Preoperative investigations allowed to recognize distal bile duct cancer in a minority of patients (41%). Operative mortality and morbidity were 3.7 and 44%, respectively. Most patients (88%) were assigned to UICC stage IV-A. Postoperative survival was not significantly better than survival of 101 patients undergoing pancreaticoduodenectomy for pancreatic ductal carcinoma; median survival was 22 months, with a 13% 5-year survival rate. Determinants of a better prognosis were UICC stage <IV-A (p = 0.05) and absence of lymphatic invasion (p < 0.01); prognostic significance of nodal involvement, tumor grading, perineural invasion, tumor size, pylorus preservation and adjuvant therapies could not be proven. Lymphatic invasion was the strongest determinant of survival on multivariate analysis (p < 0.01).

Adenocarcinoma↗
PubMed1997

Isolation of a pancreas-specific gene located on human chromosome 14q31: expression analysis in human pancreatic ductal carcinomas.

We have isolated a novel cDNA (SEL1L) that shows sequence similarities to SEL-1, a gene identified as an extragenic suppressor of the lin-12 hypomorphic mutant from Caenorhabditis elegans (7, 8). SEL1L exhibits a tissue-specific pattern of expression: a single poly(A)+ RNA species of 7.5 kb is abundantly expressed only in the pancreas of healthy individuals, whereas low to undetectable levels are observed in other adult and in some fetal tissues. Somatic hybrid panel and fluorescence in situ hybridization positioned this gene in the q31 band of human chromosome 14. The tissue-specific expression of this gene induced us to study its role in human pancreatic carcinomas. Our analysis revealed that 17% of adenocarcinomas of the pancreas did not express SEL1L to a detectable level; however, no gross genomic alterations were apparent in the few hundred kilobases of the relevant region.

Adult↗
PubMed1997

Evaluation of UICC TNM classification for pancreatic cancer. A study of 228 patients.

CONCLUSION: A different stage grouping of TNM factors can improve the predictivity of the UICC TNM classification for pancreatic cancer. Nevertheless, the Japanese Pancreas Society (JPS) classification maintains a higher prognostic value. BACKGROUND: The use of a reliable staging classification facilitates the evaluation of anticancer treatments and the correct management of patients. The aim of the present study was to evaluate the prognostic value of three modified UICC TNM classifications, obtained by different stage grouping of the UICC TNM factors, comparing their predictivity to the standard UICC and the JPS classifications. METHODS: Clinical material consisted of 228 patients who underwent resection for pancreatic cancer. The reliability of the classifications was analyzed by the following methods: univariate analysis of stage survival curves; multivariate analysis of each classification after adjusting for grading and radicality; and correlation between the patients' distribution in the stages of each classification and in survival classes. RESULTS: The following modified UICC classification allowed a better differentiation of stage II and III survival (P = 0.08) than standard UICC (P = 0.74): stage I: T1N0M0; stage II: T1N1M0/T2N0M0: stage III: T2N1M0/T3 any NM0; stage IV: M1. The JPS classification better discriminated between the different stages (P < 0.001). All classifications had an independent prognostic value by multivariate analysis. The correlation between stages and survival classes was higher for the JPS classification than either UICC TNM classification or the modified UICC classifications.

Adenocarcinoma↗
PubMed1996

Breast carcinoma detection with a combination of radiolabeled monoclonal antibodies. Promising results from immunohistochemistry studies.

BACKGROUND: Recent studies have demonstrated that the use of radiolabeled monoclonal antibodies (MoAbs) directed against tumor-associated antigens could help in the recognition of primary tumors, their extent, and their metastases by external scintigraphy (used preoperatively) or by hand-held gamma-detecting probe (GDP) (used intraoperatively). METHODS: The authors evaluated carcinoembryonic antigen (CEA), c-erb B-2 protein, and TAG-72 expression in 100 cases of breast carcinoma using F023C5 (anti-CEA), B72.3, and anti-c-erb B-2 protein MoAbs that were previously investigated for their usefulness in radioimmunoguided surgery and external scintigraphy. The goal of this study was to examine the biodistribution of each antibody in primary, multifocal, and metastatic lesions to evaluate the suitability of their simultaneous use in GDP and external scintigraphy. RESULTS: Results showed immunoreactivity for c-erb B-2 protein in 39 of 99 cases, for B72.3 in 41 of 100 cases, and for CEA in 15 of 100 cases. Multifocal lesions demonstrated positivity for c-erb B-2 protein in 37.4% of cases (6 of 16), for B72.3 in 68.8% of cases (11 of 16), and for CEA in 6.2% of cases (1 of 16). In lymph node metastases, immunoreactivity was found for c-erb B-2 protein in 36.4% of cases (12 of 33), for B72.3 in 63.7% of cases (21 of 33), and for CEA in 24.3% of cases (8 of 33). When the authors considered the immunoreactivity of all three MoAbs, the percentage of positive cases they observed was 60% in primary tumors (60 cases), 78% in lymph node metastases, and 81.2% in multifocal lesions. CONCLUSIONS: These results suggest that in vivo tumor radioimmunodetection could be improved by the use of more antibodies directed against different tumor-associated antigens.

Antibodies, Monoclonal↗
PubMed1996

CD31/PECAM-1-driven chemokine-independent transmigration of human T lymphocytes.

We assessed the relative contribution of CD31/PECAM-1 (platelet-endothelial cell adhesion molecule-1) to T lymphocyte transmigration by the use of transfected murine fibroblasts stably expressing either the human CD31/PECAM-1 or the intercellular adhesion molecule-1 (CD54/ICAM-1). Unlike CD54/ICAM-1, CD31/PECAM-1 supported migration of activated T cells in the absence of chemokines: most of the migrating lymphocytes were CD31+ and displayed a phenotype corresponding to the naive subpopulation (LFA-1 dull and CD45RA+). Migration of activated T lymphocytes through CD54/ICAM-1+ transfected monolayers could be induced by creating a chemotactic gradient with the chemokine monocyte chemotactic protein-1, and the migrating cells mainly displayed a memory phenotype (LFA-1 bright CD45RO+) under these conditions. Furthermore, we found that in transfected cells CD54/ICAM-1 is uniformly distributed along the apical surface of the cells, while CD31/PECAM-1 is concentrated at the intercellular junctions, suggesting the existence of a haptotactic gradient (i.e. a gradient of substrate- or cell-bound molecules) responsible for T cell migration. This was also confirmed by the finding that monolayers of murine fibroblasts transfected with a CD31/PECAM-1 mutant lacking the cytoplasmic domain (CD31/PECAM-1-delta cyto), which has a reduced tendency to localize at cell-cell contact areas, supported efficient adhesion but were unable to induce migration of activated T cells unless a chemotactic gradient was created. We propose that in lymphocytes, homophilic CD31/PECAM-1 adhesion may be primarily involved in transmigration of naive T cells and that its role is complementary to that of CD54/ICAM-1.

3T3 Cells↗
PubMed1996

Prognostic criteria in nonfunctioning pancreatic endocrine tumours.

To identify prognostic subgroups among non-functioning (nonsyndromic) pancreatic endocrine tumours, a series of 61 tumours were analysed systematically for macroscopic, histopathological and immunohistochemical variables potentially predictive of malignancy. High-grade nuclear atypia, elevated mitotic rate and multifocal necrosis allowed us to separate 5 poorly differentiated carcinomas from 56 well differentiated tumours. Among the latter, 29 well-differentiated carcinomas showing gross local invasion or metastases were identified. Vascular or perineural microinvasion, Ki67 proliferative index > 2%, mitotic rate > or = 2, size > or = 4 cm, capsular penetration, nuclear atypia, lack of progesterone receptors and presence of calcitonin were among the variables correlated with malignancy. The first two were the most sensitive and specific. Their presence or absence was used in the 27 tumours lacking evidence of malignancy at the time of surgery to separate 11 cases with increased risk of malignancy (in 2 of which metastases developed during follow-up) from 16 cases with limited risk. The resulting four prognostic groups of non-functioning pancreatic endocrine tumours (limited- and increased-risk tumours, well-differentiated carcinomas and poorly differentiated carcinomas) showed distinct survival curves, which were significantly affected by vascular microinvasion, Ki67 proliferative index and metastases.

Adult↗