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Biomedical subjects

Angelo Vacca

Publications and source records attributed to Angelo Vacca.

At least 19 recordsLinked to original sources
PubMed2004

Vascular endothelial growth factor-A, vascular endothelial growth factor receptor-2 and angiopoietin-2 expression in the mouse choroid plexuses.

In this study, for the first time, we investigated about the localization of VEGF-A, VEGFR-2 and Ang-2 in the choroid plexuses of the adult mouse by Western blot and immunohistochemistry. Results showed that VEGF-A stained epithelial cells, while anti-VEGFR-2 and -Ang-2 antibodies stained endothelial cells. These data suggest that Ang-2, converting blood vessels into a more plastic and immature phenotype, would provide more accessibility of VEGF-A to endothelial cells.

Age Factors↗
PubMed2004

CXCR3-binding chemokines in multiple myeloma.

The CXC chemokines I-TAC, Mig and IP10 and their receptor CXCR3 are associated with advanced-stage tumor and contribute to tumor progression, invasion and metastasis. The current study was designed to determine the expression of CXCR3 on four multiple myeloma (MM) cell lines and bone marrow plasma cells from 20 MM patients. Cell functions related to progression, such as tyrosine-kinase phosphorylation, proliferation, chemotaxis and matrix metalloproteinase-2 (MMP-2), and MMP-9 secretion were also investigated following the CXCR3/chemokine interaction. fluorescence activated cell sorting analysis revealed that three cell lines (75%) and 18 patients (90%) express the CXCR3 molecule. We demonstrated both in cell lines and fresh plasma cells that I-TAC, Mig and IP10 are able to induce tyrosine-kinase phosphorylation and chemotaxis, but not proliferation, and to increase the MMP-2 and MMP-9 gelatinolytic activity in the cell conditioned medium. Data suggest that CXCR3/chemokine loop may be important for progression of MM in terms of intramedullary and extramedullary dissemination.

Bone Marrow Cells↗
PubMed2004

Angiogenesis in acute and chronic lymphocytic leukemia.

The bone marrow microenvironment plays a crucial role in leukemogenesis. Recent studies suggest that its vascularity changes significantly during this process and that angiogenic factors are of major importance in leukemia. This review summarizes the literature concerning the relationship between angiogenesis and the progression of acute and chronic lymphocytic leukemia. It is becoming increasingly evident that agents which interfere with angiogenesis also block tumor progression and anti-angiogenic management has become a prominent aspect of pre-clinical and clinical assessment. Recent applications of anti-angiogenic agents which interfere with or block leukemia progression are reviewed.

Animals↗
PubMed2004

A new image analysis method based on topological and fractal parameters to evaluate the angiostatic activity of docetaxel by using the Matrigel assay in vitro.

Angiogenesis is regulated both by positive and negative factors that modulate the migration, proliferation, proteolytic activity, and differentiation of endothelial cells. Various in vivo and in vitro models have been developed to test the effect of angiogenic agonists or antagonists. Until very recently, morphometric methods to evaluate the effects of angiogenic inducers and inhibitors were mostly descriptive. Here, we have described a new, automatic, image analysis method to evaluate the angiostatic activity of docetaxel by using the in vitro Matrigel assay. This method allows to establish several parameters, such as dimensional (area % covered by endothelial cells and the total length of the cellular network per field), topological (the number of meshes and the number of branching points per field), and fractal (fractal dimension, lacunarity) of the capillary-like network. Following docetaxel treatment, a reduction of about 25% in the size parameters of cell network, of about 45% in branching points per field, and more 50% in mesh number were observed. The resulting fractal analysis was consistent with these findings and fractal dimension significantly correlated with both the number of branching points and the number of meshes. These results indicate that both topological and fractal parameters allowed a characterization of the spatial texture generated by endothelial cells during in vitro angiogenesis, the former being easier to implement in a computer program and faster to calculate. Finally, topological parameters seem to exhibit a wider dynamic range than the fractal ones.

Angiogenesis Inhibitors↗
PubMed2004

Melphalan versus melphalan plus busulphan in conditioning to autologous stem cell transplantation for low-risk multiple myeloma.

INTRODUCTION: High-dose chemotherapy conditioning regimens for autologous stem cell transplantation generally give similar results in multiple myeloma. We compared two regimens: melphalan versus melphalan plus busulphan. METHODS: In all, 30 untreated patients with stage III low-risk multiple myeloma were studied. After induction with three VAD courses and mobilization with cyclophosphamide 7 g/m(2) and recombinant human granulocyte-colony stimulating factor (rHuG-CSF) (10 microg/kg b.w./die), they received melphalan 200 mg/m(2) (arm A) or busulphan 16 mg/kg plus melphalan 100 mg/m(2) (arm B) for conditioning for transplantation. All patients received maintenance therapy with Interferon 3 MU x 3/week. RESULTS: Time to engraftment after transplantation was similar in both groups. All patients received rHuG-CSF after reinfusion of peripheral stem cells. No differences emerged in transplant-related infective and noninfective complications. There were no transplant-related deaths. A better response was observed in the melphalan plus busulphan regimen (85 versus 75%, P<0.05). The 5-year overall survival with this regimen was 56 versus 49% with melphalan, and the median survival was 126 months versus 108 months for melphalan (P=0.7). The median progression-free survival was 121 months for melphalan plus busulphan versus 97 months for melphalan (P=0.05). CONCLUSION: These two conditioning regimens showed similar overall response rate and overall survival, though progression-free survival was better with busulphan plus melphalan.

Adult↗
PubMed2004

Lymphatics at the crossroads of angiogenesis and lymphangiogenesis.

The lymphatic system is implicated in interstitial fluid balance regulation, immune cell trafficking, oedema and cancer metastasis. However, the sequence of events that initiate and coordinate lymphatic vessel development (lymphangiogenesis) remains obscure. In effect, the understanding of physiological regulation of lymphatic vasculature has been overshadowed by the greater emphasis focused on angiogenesis, and delayed by a lack of specific markers, thereby limiting this field to no more than a descriptive characterization. Recently, new insights into lymphangiogenesis research have been due to the discovery of lymphatic-specific markers and growth factors of vascular endothelial growth factor (VEGF) family, such as VEGF-C and VEGF-D. Studies using transgenic mice overexpressing VEGF-C and VEGF-D have demonstrated a crucial role for these factors in tumour lymphangiogenesis. Knowledge of lymphatic development has now been redefined at the molecular level, providing an interesting target for innovative therapies. This review highlights the recent insights and advances into the field of lymphatic vascular research, outlining the most important aspects of the embryo development, structure, specific markers and methods applied for studying lymphangiogenesis. Finally, molecular mechanisms involved in the regulation of lymphangiogenesis are described.

Animals↗
PubMed2004

Serum angiogenin is not elevated in patients with early B-cell chronic lymphocytic leukemia but is prognostic factor for disease progression.

The association between angiogenin and cancer progression and poor outcome in solid tumors has been documented, but its significance in leukemias has not been evaluated. Using an ELISA technique (Quantikine Human Angiogenin Immunoassay; R&D Systems), we measured serum angiogenin levels in 77 previously untreated Binet stage A B-cell chronic lymphocytic leukemia (CLL) patients. No difference in angiogenin serum levels could be found between patients (median: 295 ng/mL; range: 74-1700) and 15 age- and sex-matched healthy controls (median: 264 ng/mL; range: 29-1835) (P = NS; Mann-Whitney test). Increased angiogenin serum level was associated with higher LDH (P = 0.03) and beta2-m (P = 0.007) concentrations. However, angiogenin did not reflect the extent of bone marrow (BM) angiogenesis as evaluated by microvessel area (P = 0.611), circulating levels of vascular endothelial growth factor (VEGF) (P = 0.873) and basic fibroblastic growth factor (FGF-2) (P = 0.421). When the 25 patients with available data were stratified into the four major cytogenetic categories (normal karyotype, 13q as a sole aberration, 12q trisomy, 11q or 17p deletion) and aberrations were compared with angiogenin serum levels, no correlation was found (P = 0.651; Kruskall-Wallis test). A cut-off of angiogenin serum level corresponding to median (i.e. 330 ng/mL) or higher identified later upstaging and longer progression-free survival (PFS). The 5-yr PFS was 51.5% for patients with angiogenin levels lower than median and 85% for patients with higher values [P = 0.03; hazard ratio (HR) = 2.86; 95% CI: 1.08-6.72]. Although in multivariate analysis only Rai substages (P = 0.00001) and peripheral blood lymphocytosis (P = 0.009) retained their prognostic significance, angiogenin could be incorporated into the Rai substages thus leading to the identification of the following risk categories: (i) stage 0 (angionenin >330 ng/mL); (ii) stage 0 (angiogenin <330 ng/mL) + stage I-II (angiogenin >330 ng/mL); and (iii) stage I-II (angiogenin <330 ng/mL). The 40-month PFS were as follows: 85%, 65%, 25% (chi(2) for trend = 6.33; d.f. = 1; P = 0.01). In conclusion, serum angiogenin levels although not increased in comparison with healthy controls, may predict clinical outcome of patients with early CLL and help to refine Rai's stratification.

ADP-ribosyl Cyclase↗
PubMed2003

Vinblastine inhibits the angiogenic response induced by adrenomedullin in vitro and in vivo.

Adrenomedullin (ADM) is protumorigenic by stimulating tumor cell growth and angiogenesis. In this context, ADM is identified as a novel target for antiangiogenic therapy. In this study, we addressed the possibility that vinblastine (VBL), as demonstrated in other experimental conditions, may act as an angiostatic molecule in the angiogenic response induced by ADM in two assays, such as Matrigel tube formation in vitro and angiogenesis in the chick embryo chorioallantoic membrane (CAM) in vivo. When tested on Matrigel, ADM caused a morphogenetic effect. In fact, endothelial cells spread and aligned with each other to form branching anastomosing tubes with multicentric junctions that gave rise to a meshwork of capillary-like structures. When ADM was administered in the presence of VBL, the capillary-like tubes were interrupted, most cells were spherical, either isolated or aggregated in small clumps. In the CAM assay, ADM induced a strong angiogenic response, which was counteracted by the treatment with VBL. Overall, these observations implicate ADM as a promoter of tumor growth and a possible target for anticancer strategies, such as the use of VBL at very low, nontoxic doses. Nevertheless, the antiangiogenic activity of low-dose VBL deserves further investigation, alone or together with other antiangiogenic agents for the treatment of tumors characterized by enhanced angiogenesis.

Adrenomedullin↗
PubMed2003

Fenretinide as an anti-angiogenic agent in neuroblastoma.

Angiogenesis is a critical event in the progression of human neuroblastoma. This mini-review summarizes our literature and experimental data concerning the use of anti-angiogenic molecules, such as TNP-470 and fenretinide, in neuroblastoma treatment.

Angiogenesis Inhibitors↗
PubMed2003

Endothelial cells in the bone marrow of patients with multiple myeloma.

Endothelial cells (EC) were extracted through a lectin-based method from bone marrow of 57 patients with active multiple myeloma (MM) and compared with their healthy quiescent counterpart, human umbilical vein EC (HUVEC). MMECs exhibit specific antigens that indicate ongoing angiogenesis and embryo vasculogenesis; solid intercellular connections, hence stability of MM neovessels; and frequent interactions with plasma cells, hence tumor dissemination. They show heterogeneous antigen expression, hence existence of subsets. Their main genetic markers are indicative of a vascular phase. They show intrinsic angiogenic ability, because they rapidly form a capillary network in vitro, and extrinsic ability, because they generate numerous new vessels in vivo. They vividly secrete growth and invasive factors for plasma cells. They signal through kinases mandatory for development of neovascularization. Ultrastructurally, they are abnormal and show metabolic activation, like tumor ECs. Thalidomide heavily interferes with their functions. Vasculogenesis and angiogenesis might contribute to the MM vascular tree and progression, in the form of growth, invasion, and dissemination. In view of the heterogeneity of the antigenic phenotype of MMECs, a mixture (or a sequence) of antiangiogenic agents coupled with thalidomide would seem plausible for the biologic management of MM.

Aged↗
PubMed2003

Increased serum levels of matrix metalloproteinase-9 predict clinical outcome of patients with early B-cell chronic lymphocytic leukaemia.

BACKGROUND AND METHODS: Serum levels of matrix metalloproteinase-9 (MMP-9) which agree with progression in solid and haematological tumours were correlated to the risk of disease progression in 62 patients with early (Binet stage A) B-cell chronic lymphocytic leukaemia (CLL). Sera were taken at diagnosis and tested by an enzyme-linked immunosorbent assay. RESULTS: MMP-9 levels positively correlated with haemoglobin levels (P = 0.03) and platelet count (P = 0.03). No association was found with main clinico-haematological features representative of tumour mass, such as peripheral blood lymphocytosis, bone marrow histology, Rai substages and beta-2 microglobulin (beta-2m). A cut-off of MMP-9 levels corresponding to 33rd percentile (203 ng/mL) or higher identified earlier upstaging and shorter progression-free survival. MMP-9 was a significant prognostic marker in multivariate analysis and partially independent of Rai substages, which suggests its inclusion into such a staging system to better stratify prognostically Rai stages I and II patients. CONCLUSIONS: MMP-9 serum levels predict disease behaviour and help to refine the prognosis of stage A CLL patients.

Adult↗
PubMed2003

In vivo time-course of the angiogenic response induced by multiple myeloma plasma cells in the chick embryo chorioallantoic membrane.

In this study, we set out to make a fine characterization of the angiogenic response induced by plasma cells obtained from patients with active-multiple myeloma (MM), in comparison with cells obtained from patients with non-active MM and benign lesions such as monoclonal gammopathy of undetermined significance (MGUS), in the chick embryo chorioallantoic membrane (CAM) assay. To achieve this we investigated the time-course of the angiogenic response induced by gelatin sponges soaked in the cell suspensions and implanted on the CAM surface from day 8 to day 12 of incubation by evaluating the number of vessels, of the vessel bifurcation and the intervascular distance at 24, 48, 72 and 96 h after the implants. The results show that plasma cell suspensions obtained from patients with active MM induce a vasoproliferative response that was significantly higher than that induced by cell suspensions obtained from patients with non-active MM or with MGUS, which is also a function of the day of implantation. In fact, implants made from day 8 to day 10 induce a strong angiogenic response, whereas those made from day 11 to day 12 do not. This finding might depend on the fact that CAM endothelium exhibits an intrinsically high mitotic rate until day 10. Thereafter, the endothelial mitotic index declines rapidly, and consequently cell suspensions implanted on the CAM of successively older embryos are not able to induce a vasoproliferative response in parallel with the reduced rates of growth of the CAM's endothelial cells.

Allantoin↗
PubMed2003

Ultrastructural analysis of mast cell recovery after secretion by piecemeal degranulation in B-cell non-Hodgkin's lymphoma.

Mast cells (MC) are critical for a number of pathological conditions, including acute and chronic inflammation and tumor angiogenesis. We have previously demonstrated in B-cell non-Hodgkin's lymphoma (B-NHL) the presence of an heterogeneous population of MC characterized by granules with a morphological semilunar appearance, or piecemeal partial degranulation (PMD), and containing scrolls. With the aim to further elucidate the morphological features of MC in B-NHL, in the present study an ultrastructural analysis of MC recovery after secretion by PMD in B-NHL samples has been carried out. Results indicate that PMD is identified by the presence of partially or completely empty granule containers in the cytoplasm, considered as the morphological endpoint of secretion by PMD. Granule refilling after PMD implies condensation of dense granule matrix material leading to the highly characteristics morphological patterns described in this paper. After the recovery from secretion by PMD in B-NHL, mature MC with full complement of granules displaying crystal, particle, scroll, and mixed patterns are recognizable. We believe that the images presented here, in the absence of MC mitosis, support the possibility that in B-NHL, MC after PMD, refill empty granule containers in situ, as seen in MC during the angiogenic phase of wound-healing, and that both events, PMD and recovery of MC after their degranulation, occur during biological processes in which MC and angiogenesis are strictly interconnected.

Cytoplasmic Granules↗
PubMed2003

Angiogenesis and anti-angiogenesis in hematological malignancies.

Although it is well established that the growth of solid tumors requires vigorous neovascularization, it has been assumed that leukemias and other hematological malignancies do not depend on angiogenesis. However, the role of angiogenesis in growth and survival of neoplastic cells of the hematopoietic system has recently been recognized, and provides a rationale for novel therapeutic approaches to hematological malignancy. This review summarizes the literature concerning the relationship between angiogenesis and disease progression of several hematological malignancies. It is becoming increasingly evident that agents that interfere with blood vessel formation also block tumor progression, and, accordingly, antiangiogenic therapy has gained much interest as a potential adjunct to conventional therapy of many hematological malignancies. Recent successful applications of antiangiogenic agents that interfere or block the progression of hematological malignancies are evaluated in light of recent demonstrations of potent angiogenic activity of several hematopoietic growth factors. A novel finding regarding the role of angiogenesis in hematological malignancies, which accounts for many clinical observations as well as the apparent independence of these tumors on marrow vascularity, is presented. The information presented in this review will facilitate the design of future clinical trials using antiangiogenic agents for the treatment of hematological malignancies and will provide a basis for the design of experiments undertaken to define the mechanisms involved, mechanisms that may shed new light on the pathology of hematological malignancies.

Angiogenesis Inhibitors↗
PubMed2003

Thalidomide: a new anticancer drug?

Experimental studies have demonstrated that thalidomide (Thal), a drug developed as a sedative, has antitumoural properties. The possible antitumour mechanisms of action involve: inhibition of angiogenesis, cytokine-mediated pathways, modulation of adhesion molecules, inhibition of cyclooxygenase-2 and stimulation of immuno response. Therefore, Thal is under clinical evaluation in oncology. This paper provides an overview of the data currently available in literature regarding, in terms of activity and toxicity, the use of Thal in cancer patients. Multiple myeloma is so far the most responsive malignancy. A moderate activity has been documented in certain solid tumours: glioblastoma multiforme, renal cell carcinoma and malignant melanoma. Tolerability is generally satisfactory with peripheral neuropathy being the most relevant dose-dependent toxicity. The more frequent, but moderate side effects are: somnolence, constipation, dizziness and fatigue. More studies are needed to properly evaluate the anticancer activity of Thal alone or in combination with other anticancer treatments. Preliminary studies suggest promising results of Thal in combinations with corticosteroids and cytotoxic drugs as front-line therapy of multiple myeloma. Regarding therapy of solid tumours in the adult, combination with chemotherapy, radiation therapy and molecular-targeting compounds are under investigation.

Animals↗