Biomedical subjects

A Vacca

Publications and source records attributed to A Vacca.

At least 55 records · Page 3Linked to original sources

PubMed2003

Erythropoietin as an angiogenic factor.

Erythropoietin (Epo) is produced by the fetal liver and adult kidney and is an essential stimulator of erythropoiesis. It has, however, been shown to modulate host cellular signal transduction pathway to perform many other functions. New sites of Epo production have been found, such as the female reproductive organs and central nervous system. This review summarizes the involvement of Epo in the regulation of angiogenesis in both normal and pathological conditions.

Angiogenesis Inducing Agents↗

PubMed2003

Erythropoietin as an angiogenic factor in gastric carcinoma.

AIMS: Previous studies have shown that increased vascularity is associated with haematogenous metastasis and poor prognosis in gastric cancer. The role of erythropoietin (Epo) in angiogenesis has not been completely clarified, although its involvement has been reported. In this study we correlated microvascular density and Epo receptor (Epo-R) expression in endothelial and tumour cells with histopathological type in gastric cancer. METHODS AND RESULTS: Specimens of primary gastric adenocarcinomas obtained from 40 patients who had undergone curative gastrectomy were investigated immunohistochemically by using anti-CD31 and anti-Epo-R antibodies. Stage IV gastric carcinoma had a higher degree of vascularization than other stages, and Epo-R expression in both endothelial and tumour cells increased in parallel with malignancy grade and was highly correlated with the extent of angiogenesis. CONCLUSIONS: Epo-R level correlates with angiogenesis and progression of patients with gastric carcinoma and we suggest that Epo might have a trophic effect on the vasculature of the gastrointestinal tract. Understanding mechanisms of gastric cancer angiogenesis provides a basis for a rational approach to the development of an anti-angiogenic therapy in patients with gastric cancer.

Adenocarcinoma↗

PubMed2003

Detection of early impairment of coronary flow reserve in patients with systemic sclerosis.

OBJECTIVE: To investigate whether coronary flow reserve (CFR), measured by a new non-invasive method, is impaired early in patients with systemic sclerosis (SSc) and whether CFR impairment correlates with clinical or functional measures, or both. METHODS: 27 patients with SSc without clinical evidence of ischaemic heart disease and 23 control group subjects matched for age and sex were studied. CFR was evaluated in the left anterior descending coronary artery (LAD) with a new non-invasive method: contrast (Levovist) enhanced transthoracic Doppler during adenosine infusion. The pulsed wave Doppler examination of blood flow velocity was recorded in the LAD at rest and after maximum vasodilatation by adenosine infusion. RESULTS: In patients with SSc, without clinical evidence of ischaemic heart disease, CFR was impaired (p=0.0001). 14/27 patients with SSc had severe reduction of the CFR (< or =2.5) compared with controls (p=0.002). A non-significant trend between mean CFR and the severity and duration of the disease was also seen. CONCLUSIONS: CFR is often reduced in patients with SSc, suggesting early preclinical cardiac involvement in SSc. This impairment in coronary microvasculature is detectable by a non-invasive echocardiographic method and in this study was more common in the diffuse form of SSc.

Adult↗

PubMed2003

Allogeneic gene-modified tumour cells in metastatic kidney cancer. Preliminary report.

An allogeneic irradiated RCC cell line, engineered to produce IL-2 (ACHN-IL-2), admixed with autologous metastatic formalin-treated tumour cells, was used to vaccinate ten MRCC patients in progression of disease in spite of IL-2 immunotherapy. The cells were administered subcutaneously and/or intra-tumourally. Sixty-four MRCC patients in progressive disease, not treated by vaccination but receiving similar IL-2 immunotherapy, were considered as the control group. Patients received 4-16 injections (mean 9 +/- 4), containing an average of 10.6 x 10(7) +/- 7.7 x 10(7) ACHN-IL-2-transfected cells (a minimum of 4 x 10(7), and a maximum of 31 x 10(7)). Four patients also received intra-tumour injections. Vaccination was administered during 30-418 days, and the follow-up continued for 649 +/- 353 days (190-1342). Throughout this period, the patients continued receiving the previously set immunotherapy treatment. No adverse side effects related to the treatment were observed. One complete and one partial tumour response were observed, as well as two stable and one no-relapse disease. All but one patient died. Responding patients resumed progression in 4-11 months and died 18 and 36 months after beginning the vaccine therapy. In spite of the small number of treated patients, Wilcoxon's test showed a significant (P < 0.05) improvement of the survival in the vaccinated group compared to that of the control. The described vaccination protocol seems safe, devoid of adverse side effects and promising. It warrants further investigation.

Aged↗

PubMed2002

Multiple myeloma and mycosis fungoides in the same patient: clinical, immunologic, and molecular studies.

The coexistence of multiple myeloma (MM) and mycosis fungoides (MF), and hence of both B- and T-cell neoplastic clones, is a rare event. We describe a case of plaque-stage MF associated with IgG lambda MM. The clinical onset of MF preceded that of MM, supporting the hypothesis that MF predisposed to the development of the B-cell proliferative disorder. The skin tumor cells were found to originate from CD4(+) T-lymphocytes, characterized by a V beta 8 receptor and no proviral human T-lymphotropic virus (HTLV)-I monoclonal integration. They also displayed a polarized Th1-type cytokine profile containing mRNAs for interleukin (IL)-2, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-beta, but not for IL-4, IL-5, or IL-10. The CD8(+)/CD57(+) suppressor-cytotoxic subpopulation was significantly increased in the peripheral blood and was associated with MM progression. Expression of p16INK4A, a gene from the INK family that inhibits cyclin-dependent kinases and regulates the cell cycle, was lacking in MF cells and bone marrow (BM) plasma cells. The p16INK4A gene was silenced by hypermethylation, suggesting that it plays a role in the early phase of the pathogenesis of both diseases. Thus, a lymphoid precursor cell presumably contains aberrations that induce the development of both clonal diseases in a multistep process.

Blotting, Western↗

PubMed2002

Inhibition of endothelial cell functions and of angiogenesis by the metastasis inhibitor NAMI-A.

NAMI-A is a ruthenium-based compound with selective anti-metastasis activity in experimental models of solid tumours. We studied whether this activity was dependent on anti-angiogenic ability of NAMI-A. We thus investigated its in vitro effects on endothelial cell functions necessary for angiogenesis to develop, as well as its in vivo effects in the chick embryo chorioallantoic membrane model. Endothelial cell proliferation, chemotaxis, and secretion of the matrix-degrading enzyme metalloproteinase-2 were inhibited by NAMI-A in a dose-dependent manner, and without morphologic signs of cell apoptosis or necrosis. Lastly, NAMI-A displayed a dose-dependent in vivo anti-angiogenic activity in the chorioallantoic membrane model. These data suggest that the anti-angiogenic activity of NAMI-A can contribute to its anti-metastatic efficacy in mice bearing malignant solid tumours.

Angiogenesis Inhibitors↗

PubMed2002

Angiogenesis and anti-angiogenesis in neuroblastoma.

Angiogenesis is a biological process by which new capillaries are formed from pre-existing vessels. It occurs in physiological and pathological conditions, such as tumours, where a specific critical turning point is the transition from the avascular to the vascular phase. Tumour angiogenesis depends mainly on the release by neoplastic cells of growth factors specific for endothelial cells that able to stimulate the growth of the host's blood vessels. This review summarises the literature concerning the relationship between angiogenesis and progression in human neuroblastoma, the most common extracranial solid tumour of infancy and childhood. It is becoming increasingly evident that agents which interfere with blood vessel formation also block tumour progression. Accordingly, anti-angiogenic tumour therapy has gained much interest in preclinical and clinical assessments. The recent applications of anti-angiogenic agents which interfere or block neuroblastoma progression are reviewed.

Angiogenesis Inhibitors↗

PubMed2002

Correlation of bone marrow angiogenesis and mast cells with tryptase activity in myelodysplastic syndromes.

Bone marrow samples from 30 patients with myelodysplastic syndromes (MDS) grouped according to the International Prognostic Scoring System for MDS were investigated for counts of microvessels, total metachromatic mast cells (MC) and MC expressing tryptase, an angiogenesis-inducing molecule. Counts were higher in patients with a poor prognosis. The observation of a high correlation between microvessel counts and both total metachromatic and tryptase-reactive MC in all samples suggests that angiogenesis in MDS increases with their progression and that MC may intervene in the angiogenic response in MDS through tryptase contained in their secretory granules.

Antigens, CD34↗

PubMed2002

Anti-angiogenic activity of the purine analog 6-thioguanine.

The antimetabolite 6-thioguanine (6-TG) is utilized in the management of acute myelogenous leukemia (AML). Angiogenesis is a possible therapeutic target in hematologic tumors. Thus, we addressed the possibility that 6-TG may also act as an anti-angiogenic molecule. 6-TG inhibited endothelial cell proliferation triggered by fibroblast growth factor-2 (FGF2) and vascular endothelial growth factor (VEGF) and delayed the repair of a mechanically wounded endothelial cell monolayer. Also, 6-TG inhibited sprouting within fibrin gel, morphogenesis on Matrigel, and collagen gel invasion by endothelial cells. 2-Aminopurine was ineffective. In vivo, 6-TG inhibited basal, VEGF-induced, and FGF2-induced vascularization in the chick embryo chorioallantoic membrane and prevented neovascularization triggered by leukemia LIK cells or their conditioned medium. Finally, bone marrow vascularization in AML patients was decreased to control values in the early remission phase and persisted unvaried after 8-12 months of maintenance therapy with 6-TG. Thus, 6-TG inhibits different steps of the angiogenesis process in vitro and exerts a potent anti-angiogenic activity in vivo. Its anti-angiogenic activity, together with its antimetabolite activity towards tumor cells, may contribute to its action during maintenance therapy in AML. These results suggest a new rationale for the use of purine analogs in the management of AML.

2-Aminopurine↗

PubMed2002

Angiogenesis extent and expression of matrix metalloproteinase-2 and -9 agree with progression of ovarian endometriomas.

BACKGROUND: Changes in angiogenesis and expression of extracellular matrix-degrading enzymes have been substantiated in tumour changeover and progression. METHODS: Tissues from 44 biopsies of stage III and IV ovarian endometriomas, and 10 biopsies of normal (control) endometrium were investigated immunohistochemically to count microvessels, and by in situ hybridization to assess the expression of mRNA of matrix metalloproteinase-2 (MMP-2) and MMP-9. Implants of the tissues were investigated in the chick embryo chorioallantoic membrane (CAM) assay to determine their angiogenic capacity. RESULTS: The endometriomas displayed significantly higher counts than normal endometria and the highest values were associated with the deepest invasion level (stage IV). Microvessels localized in close association with ectopic endometrial cells in the form of winding and arborized tubes, often dilated in microaneurysmatic segments. These were absent in normal endometrium. Expression of MMP-2 and MMP-9 mRNA, evaluated as percentages of positive biopsies and intensity of expression, was up-regulated in endometriomas and more pronounced in stage IV. MMP-2 and MMP-9 mRNA were also expressed by host stromal cells, including microvascular endothelial cells, fibroblasts and macrophages, whereas the control endometrium showed very little expression of MMP-2 mRNA in a few endothelial cells and no expression of MMP-9 mRNA. Implants from stage IV endometrioma induced a more intense vasoproliferative response than those from stage III, while no vasoproliferative response was induced by the normal endometrium. CONCLUSION: These data suggest that angiogenesis and degradation of extracellular matrix occur together in endometriosis and are more pronounced in stage IV, and that endometriosis cells and some host stromal cell populations co-operate in disease progression.

Adult↗

PubMed2002

Increased level of HLA-B27 expression in ankylosing spondylitis patients compared with healthy HLA-B27-positive subjects: a possible further susceptibility factor for the development of disease.

OBJECTIVE: In B27 transgenic rats, susceptibility to the development of a spondyloarthropathy-like disease has been shown to correlate with the level of B27 transgene expression on lymphoid cells. The aim of this work was to study HLA-B27 molecule expression in peripheral blood mononuclear cells (PBMCs) from patients with ankylosing spondylitis (AS) and from normal controls (NC). METHODS: Twenty B27(+) AS patients and 16 B27(+) NC were studied. HLA-B27 whole molecules and free heavy chains (HCs) and total HLA class I molecules were evaluated at the surface of PBMCs by immunofluorescence and flow cytometry. B27 subtypes were defined with the PCR-SSP (polymerase chain reaction-sequence-specific primer) technique. Cellular activation was evaluated by the expression of CD69, CD25 molecules and interferon gamma (IFN-gamma) production. RESULTS: B27 expression was 55,536.3+/-18,961.0 MESF (molecules of equivalent soluble fluorochromes) units in AS and 25,936.0+/-12,117.5 MESF in NC (P=0.00009), total HLA class I expression was 448,840.2+/-136,293.8 MESF in AS and 533,494.4+/-232,931.1 MESF in NC (not significant), HC expression was 10,593.4+/-6,396.1 MESF in AS and 14,843.0+/-7,544.2 MESF in NC (not significant). The higher B27 expression in the SA group was not due to higher cell activation as it was not correlated with CD69 and CD25 expression in PBMCs or with the level of IFN-gamma. HLA-B27 expression did not correlate with indexes of disease status [Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI) and Bath Ankylosing Spondylitis Metrology Index (BASMI)]. CONCLUSIONS: We found greater expression of HLA-B27 molecules in patients with AS than in healthy subjects. This phenomenon was not accompanied by general up-regulation of HLA class I molecules or by greater expression of classical T-cell activation markers. On this basis we propose that the higher expression of the HLA-B27 molecules is a further predisposing factor for the development of AS.

Acute Disease↗

PubMed2002

Sustained normalization of cerebral blood-flow after iloprost therapy in a patient with neuropsychiatric systemic lupus erythematosus.

We report the case of a 30-year-old caucasian woman affected by SLE who developed neurological symptoms (prosopagnosia and visual-spatial agnosia) after nine years of disease. Brain MRI showed no abnormalities while a brain SPECT scan showed diffuse uptake defects and hypoperfusion areas in the right and left frontal-parietal regions. At that time the patient was on hydroxychloroquine (400 mg/day) and oral prednisolone (0.5 mg/kg/day) as maintenance therapy. One year later the patient showed worsening of Raynaud's phenomenon with digital dystrophic lesions and was therefore treated with an intravenous infusion of Iloprost (1.5 ng/kg/min per 6h/day for 10 days consecutively), while baseline treatment remained unchanged. One month later the patient showed a dramatic improvement in her cognitive function and subsequent SPECT scans showed the gradual disappearance of perfusion abnormalities. This first report of Iloprost treatment in CNS lupus suggests the potential therapeutic usefulness of this drug in patients with SLE and functional CNS involvement.

Adult↗

PubMed2001

Chorioallantoic membrane capillary bed: a useful target for studying angiogenesis and anti-angiogenesis in vivo.

The chick embryo chorioallantoic membrane (CAM) is an extraembryonic membrane that is commonly used in vivo to study both angiogenesis and anti-angiogenesis. This review 1) summarizes the current knowledge about the structure of the CAM's capillary bed; 2) discusses the controversy about the existence of a single blood sinus or a capillary plexus underlying the chorionic epithelium; 3) describes a new model of the CAM vascular growth, namely the intussusceptive mode; 4) reports findings regarding the role played by endogenous fibroblast growth factor-2 in CAM vascularization; and 5) addresses the use and limitations of the CAM as a model for studying angiogenesis and anti-angiogenesis.

Allantois↗

PubMed2001

Inhibition of neuroblastoma-induced angiogenesis by fenretinide.

Retinoids are a class of natural or synthetic compounds that participate in the control of cell proliferation, differentiation and fetal development. The synthetic retinoid fenretinide (HPR) inhibits carcinogenesis in various animal models. Retinoids have also been suggested to be effective inhibitors of angiogenesis. The effects of HPR on certain endothelial cell functions were investigated in vitro, and its effects on angiogenesis was studied in vivo, by using the chorioallantoic membrane (CAM) assay. HPR inhibited vascular endothelial growth factor- (VEGF-) and fibroblast growth factor-2- (FGF-2)-induced endothelial cell proliferation without affecting endothelial motility; moreover, HPR inhibited growth factor-induced angiogenesis in the CAM assay. Furthermore, a significant antiangiogenic potential of HPR has also been observed in neuroblastoma (NB) biopsy-induced angiogenesis in vivo. We previously demonstrated that supernatants derived from NB cell lines stimulated endothelial cell proliferation. In the present study, we found that this effect was abolished when NB cells were incubated in the presence of HPR. VEGF- and FGF-2-specific ELISA assays, performed on both NB cells derived from conditioned medium and cellular extracts, indicated no consistent effect of HPR on the level of these angiogenic cytokines. Moreover, RT-PCR analysis of VEGF and FGF-2 gene expression confirmed the above lack of effect. HPR was also able to significantly repress the spontaneous growth of endothelial cells, requiring at least 48-72 hr of treatment with HPR, followed by a progressive accumulation of cells in G(1) at subsequent time points. Finally, immunohistochemistry experiments performed in the CAM assay demonstrated that endothelial staining of both VEGF receptor 2 and FGF-2 receptor-2 was reduced after implantation of HPR-loaded sponges, as compared to control CAMs. These data suggest that HPR exerts its antiangiogenic activity through both a direct effect on endothelial cell proliferative activity and an inhibitory effect on the responsivity of the endothelial cells to the proliferative stimuli mediated by angiogenic growth factors.

Adenocarcinoma↗

PubMed2001

Beryllium(II) complexes of the Kläui tripodal ligand cyclopentadienyltris(diethylphosphito-p)cobaltate(-).

The interactions of the beryllium(II) ion with the cyclopentadienyltris(diethylphosphito-P)cobaltate monoanion, L(-), have been investigated, in aqueous solution, by synthetic methods, potentiometry, ESMS, and (1)H, (31)P, and (9)Be NMR spectroscopy. L(-) has been found able to displace either two or three water molecules in the beryllium(II) coordination sphere, to form mononuclear, dinuclear, and trinuclear derivatives, in which the metal ion is pseudotetrahedrally coordinated. The species [BeL(H(2)O)](+) and [Be(2)L(2)(mu-OH)](+) have been identified in solution while complexes of formula BeL(2) and [Be(3)L(4)](ClO(4))(2) have been isolated as solid materials. The species [BeL(OPPh(2))](+), closely related to [BeL(H(2)O)](+), has been characterized in acetone solution and isolated as tetraphenylborate salt. The structure of the unusual trimeric complex [Be(3)L(4)](2+) has been elucidated by an unprecedented 2D (9)Be-(31)P NMR correlation spectrum showing the presence of a single central beryllium nucleus and two equivalent terminal beryllium nuclei. The three beryllium centers are held together by four cobaltate ligands, which display two different bonding modes: two ligands are terminally linked with all the three oxygen donors to one terminal beryllium, and the other two bridge two metal centers, sharing the oxygen donors between central and terminal beryllium atoms.

Beryllium↗

PubMed2001

Monocyte-macrophage system and polymorphonuclear leukocytes in workers exposed to low levels of metallic mercury.

Our previous research (Soleo L, Vacca A, Vimercati L et al. Occup Environ Med 1997;54:437-442) showed a reduction in tumor necrosis factor-alpha (TNF-alpha) serum levels in workers with prolonged exposure to low doses of inorganic mercury, suggesting an in vivo functional defect of the monocyte-macrophage system. On this basis, here we wondered whether workers exposed to lower doses of metallic mercury displayed possible changes in the monocyte-macrophage system. In this particular cohort of workers, we also sought for the effects of the exposure on the polymorphonuclear leukocytes (PMNL) chemotaxis. The monocyte-macrophage system and the natural killer (NK) cells were examined in 19 exposed workers and in 25 unexposed workers, as the control group (controls). Specifically, the circulating monocyte-macrophage cells and their CD13, CD15 and CD33 subsets, serum cytokines (IL-8, GM-CSF and TNF-alpha) and the NK cells were analyzed. In seven exposed and seven controls randomly chosen workers the PMNL chemotaxis was also assessed. The selected indicator of mercury exposure were the levels of mercury in the urine (U-Hg), that was significantly higher in exposed workers than the controls (9.7 +/- 5.5 microg/l and 2.4 +/- 1.2 microg/l, respectively). None of the exposed workers had shown signs of either acute or chronic inorganic mercury toxicity or any form of hypersensitivity. Several immunological variables tested, monocyte-macrophage cells and their subsets, NK cells and serum cytokines overlapped between the exposed and the control workers. When the workers were considered as a whole (exposed plus controls), no correlation was found between current U-Hg and all immunological parameters. However, when exposed workers were studied separately, an inverse correlation was disclosed between cumulative U-Hg and cells (as percentage) expressing the CD13 (r = -0.599; P = 0.007) and CD15 (r = -0.614; P = 0.005) molecules, and NK cells (r = -0.455; P = 0.05). Moreover, a significant impairment in the PMNL chemotaxis (t = 3.70; P = 0.003) was observed in the exposed workers. The results of our study suggest that the exposure to very low levels of metallic mercury led to subtle impairment of circulating monocyte and NK cells (as percentages) according to the increase in U-Hg levels, as well as of the PMNL chemotactic function in this particular group of workers, even though they remain clinically asymptomatic. Therefore, we suggest that impairment of these parameters provide a sensitive indicator of metallic mercury and other chemical contaminants present in the environment.

Adult↗

PubMed2001

Angiogenesis extent and expression of matrix metalloproteinase-2 and -9 correlate with progression in human neuroblastoma.

In human tumors changes in angiogenesis and expression of extracellular matrix-degrading enzymes occur simultaneously during invasion and metastasis. Tissues from 20 biopsies of human neuroblastoma (NB) were investigated immunohistochemically by using an antibody against factor VIII to determine their microvessel number, and by in situ hybridisation to determine the expression of mRNA of the matrix metalloproteinase-2 (MMP-2) and MMP-9. The extent of angiogenesis and the expression of the MMP-2 and MMP-9 mRNA were upregulated in advancing stages. These in situ data suggest that angiogenesis and degradation of extracellular matrix occur simultaneously with NB tumor progression.

Child↗

PubMed2001

Bone marrow angiogenesis in patients with active multiple myeloma.

Factor VIII-related antigen (FVIII-RA)-positive microvessel areas were measured by both immunohistochemistry and computerized image analysis in patients with active multiple myeloma (MM), nonactive MM, and monoclonal gammopathies of undetermined significance (MGUS). A five-to sixfold larger area was found in patients with active MM compared to the other two groups. Aquaporin 1 (AQP1)-positive microvessel areas, measured with the same techniques on adjacent tissue sections, were also increased in active MM, and tended to be larger than and closely correlated with the FVIII-RA areas. Numerous mast cells were found in the bone marrow of active MM patients, and counts were strictly correlated with the microvessel density. The conditioned medium (CM) of bone marrow plasma cells from active MM patients stimulated endothelial cell proliferation and chemotaxis, monocyte chemotaxis, and angiogenesis in vivo (assessed by the chick embryo chorioallantoic membrane [CAM] system) more strongly and frequently than the CM of patients with nonactive MM and MGUS. Immunoassay of plasma cell lysates gave significantly higher levels of fibroblast growth factor-2 (FGF-2) in patients with active MM than in the other two groups, and a neutralizing anti-FGF-2 antibody inhibited by 46% to 68% the biological activity exerted by the CM in vitro and in the CAM. In situ hybridization of bone marrow plasma cells and zymography of CM showed that patients with active MM express higher levels of matrix metalloproteinase-2 (MMP-2) mRNA and protein than those with nonactive MM and MGUS, whereas MMP-9 expression and secretion overlapped in all groups. Overall data indicate that patients with active MM represent the vascular phase of plasma cell tumors that is induced, at least partly, through FGF-2 and MMP-2. Mast cells possibly contribute to the vascular phase via angiogenic factors in their secretory granules. Both angiogenesis and MMP-2 secretion can account for intramedullary and extramedullary spreading of plasma cells in patients with active MM.

Angiogenesis Inducing Agents↗