Biomedical subjects

Franco Dammacco

Publications and source records attributed to Franco Dammacco.

At least 19 recordsLinked to original sources

PubMed2006

Angiogenesis and anti-angiogenesis in hepatocellular carcinoma.

Experimental and clinical data indicate that in human hepatocellular carcinoma (HCC) tumor progression is associated with angiogenesis and that an increase in microvascular density is associated with a poor prognosis. This review summarizes the literature concerning the relationship between angiogenesis and progression in HCC. It is becoming increasingly evident that agents which interfere with blood vessel formation also block tumor progression. Accordingly, anti-angiogenic tumor therapy has gained much interest in preclinical and clinical assessments. The recent applications of anti-angiogenic agents which interfere or block HCC progression are reviewed.

Angiogenesis Inhibitors↗

PubMed2006

Myeloma bone disease: pathogenetic mechanisms and clinical assessment.

Bone disease in multiple myeloma (MM) leads to progressive devastation of the skeleton and is the most severe cause of morbidity. Its pathogenetic mechanisms are not fully defined, though the current evidence points to hyperactivation of osteoclasts (OC) in presence of a major defect of bone repairing in erosion sites due to osteoblast (OB) impairment. Bone resorption, however, is promoted by early OB, namely stromal cells that respond to chronic stimulation by myeloma cells by enhancing marrow levels of RANKL and other osteoclastogenic factors and thus accelerating the maturation of OC progenitors. In myeloma bone disease (MBD), OBs are systematically defeated by a number of inhibiting effects induced by the malignant clone within the marrow microenvironment. Thus, MBD primarily affects the OB lineage, particularly in overt MM, where serum markers of osteoblastogenesis, such as osteocalcin and osteoprotegerin, are extremely low in contrast with their slight increase in inactive MM. These markers, in association with others of bone turnover (RANKL, MIP-1alpha, type I collagen telopeptides such as NTX and CTX) may be used in the clinical assessment of MBD as well as to monitor the efficacy of bisphosphonate in delaying the progressive skeletal destruction.

Bone Diseases↗

PubMed2006

Loss of inhibitory semaphorin 3A (SEMA3A) autocrine loops in bone marrow endothelial cells of patients with multiple myeloma.

Vascular endothelial growth factor165 (VEGF165) and semaphorin3A (SEMA3A) elicit pro- and antiangiogenic signals respectively in endothelial cells (ECs) by binding to their receptors VEGFR-2, neuropilin-1 (NRP1), and plexin-A1. Here we show that the VEGF165-driven angiogenic potential of multiple myeloma (MM) ECs is significantly higher than that of monoclonal gammopathy of undetermined significance (MGUS) ECs (MGECs) and human umbilical vein (HUV) ECs. This is probably due to a constitutive imbalance of endogenous VEGF165/SEMA3A ratio, which leans on VEGF165 in MMECs but on SEMA3A in MGECs and HUVECs. Exogenous VEGF165 induces SEMA3A expression in MGECs and HUVECs, but not in MMECs. Moreover, by counteracting VEGF165 activity as efficiently as an anti-VEGFR-2 antibody, exogenous SEMA3A restrains the over-angiogenic potential of MMECs. Our data indicate that loss of endothelial SEMA3A in favor of VEGF165 could be responsible for the angiogenic switch from MGUS to MM.

Bone Marrow Cells↗

PubMed2006

Bortezomib mediates antiangiogenesis in multiple myeloma via direct and indirect effects on endothelial cells.

Bone marrow angiogenesis plays an important role in the pathogenesis and progression in multiple myeloma. Recent studies have shown that proteasome inhibitor bortezomib (Velcade, formerly PS-341) can overcome conventional drug resistance in vitro and in vivo; however, its antiangiogenic activity in the bone marrow milieu has not yet been defined. In the present study, we examined the effects of bortezomib on the angiogenic phenotype of multiple myeloma patient-derived endothelial cells (MMEC). At clinically achievable concentrations, bortezomib inhibited the proliferation of MMECs and human umbilical vein endothelial cells in a dose-dependent and time-dependent manner. In functional assays of angiogenesis, including chemotaxis, adhesion to fibronectin, capillary formation on Matrigel, and chick embryo chorioallantoic membrane assay, bortezomib induced a dose-dependent inhibition of angiogenesis. Importantly, binding of MM.1S cells to MMECs triggered multiple myeloma cell proliferation, which was also abrogated by bortezomib in a dose-dependent fashion. Bortezomib triggered a dose-dependent inhibition of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) secretion by the MMECs, and reverse transcriptase-PCR confirmed drug-related down-regulation of VEGF, IL-6, insulin-like growth factor-I, Angiopoietin 1 (Ang1), and Ang2 transcription. These data, therefore, delineate the mechanisms of the antiangiogenic effects of bortezomib on multiple myeloma cells in the bone marrow milieu.

Angiogenesis Inhibitors↗

PubMed2006

In-vitro functional phenotypes of plasma cell lines from patients with multiple myeloma.

Seven plasma cell lines from patients with smoldering (group A) and overt myeloma (group B) were investigated for both phenotypic markers and in-vitro properties, including sensitivity to apoptosis, cytotoxicity, cell adhesion, chemotaxis and bone interaction. Cell lines from group A underwent apoptosis whereas those from group B were apparently resistant, promoted cytotoxicity in target cells and enhanced both adhesion and migratory functions upon appropriate activators. In addition, MCC-2, a group B cell line from a patient with severe osteolytic disease of the skeleton produced erosive lacunae on bone substrates, whereas this effect was almost absent with cell lines from group A. Concurrent deregulation of relative markers, in combination with peculiar properties including resistance to apoptosis and high cytotoxic potential, as well as adhesion, chemotaxis and bone pathophysiology interactions, may thus identify myeloma cells with aggressive phenotype driving these biological activities in vitro and perhaps in vivo.

Apoptosis↗

PubMed2006

Antibody production and in vitro behavior of CD27-defined B-cell subsets: persistent hepatitis C virus infection changes the rules.

There is growing interest in the tendency of B cells to change their functional program in response to overwhelming antigen loading, perhaps by regulating specific parameters, such as efficiency of activation, proliferation rate, differentiation to antibody-secreting cells (ASC), and rate of cell death in culture. We show that individuals persistently infected with hepatitis C virus (HCV) carry high levels of circulating immunoglobulin G (IgG) and IgG-secreting cells (IgG-ASC). Thus, generalized polyclonal activation of B-cell functions may be supposed. While IgGs include virus-related and unrelated antibodies, IgG-ASC do not include HCV-specific plasma cells. Despite signs of widespread activation, B cells do not accumulate and memory B cells seem to be reduced in the blood of HCV-infected individuals. This apparent discrepancy may reflect the unconventional activation kinetics and functional responsiveness of the CD27+ B-cell subset in vitro. Following stimulation with T-cell-derived signals in the absence of B-cell receptor (BCR) engagement, CD27+ B cells do not expand but rapidly differentiate to secrete Ig and then undergo apoptosis. We propose that their enhanced sensitivity to BCR-independent noncognate T-cell help maintains a constant level of nonspecific serum antibodies and ASC and serves as a backup mechanism of feedback inhibition to prevent exaggerated B-cell responses that could be the cause of significant immunopathology.

Adult↗

PubMed2005

Generation of biologically active linear and cyclic peptides has revealed a unique fine specificity of rituximab and its possible cross-reactivity with acid sphingomyelinase-like phosphodiesterase 3b precursor.

Heterogeneity of the effector functions displayed by rituximab and other anti-CD20 monoclonal antibodies (mAbs) apparently recognizing the same CD20 epitope suggests that additional mechanisms, probably related to mAb fine specificity, are responsible for B-cell depletion. To improve our understanding of rituximab's function, its fine specificity was investigated by means of phage display peptide library (PDPL)-expressing 7-mer cyclic (c7c) or 7-/12-mer linear peptides. Rituximab-specific c7c PDPL-derived clone insert sequences expressed the motif A(S)NPS overlapping the human CD20 170ANPS173. P172 was the most critical for rituximab binding, since its replacement with S172 (of mouse CD20) abolished the reactivity. The WPXWLE motif expressed by the linear PDPL-derived clone insert sequences could only be aligned to the reverse-oriented 161WPXWLE156 of acid sphingomyelinase-like phosphodiesterase 3b precursor (ASMLPD), though linear peptides bearing WPXWLE competed with cyclic ones for rituximab-paratope binding. Anti-CD20 mAb 1F5 only displayed a reactivity profile similar to that of rituximab, which also reacted with ASMLPD-derived peptides. Peptides induced antibodies with specificity and effector functions similar to those of rituximab. Our results show a unique fine specificity of rituximab, define the molecular basis for the lack of rituximab reactivity with mouse CD20 (mCD20), and the potential of targeting CD20 in an active immunotherapy setting. A possible rituximab interaction with ASMLPD is suggested.

Amino Acid Motifs↗

PubMed2005

Thalidomide downregulates angiogenic genes in bone marrow endothelial cells of patients with active multiple myeloma.

PURPOSE: To study the antiangiogenic effect of thalidomide. PATIENTS AND METHODS: The expression of key angiogenic genes was studied in bone marrow endothelial cells (ECs) of patients with active and nonactive multiple myeloma (MM), monoclonal gammopathies unattributed/unassociated (MG[u]), diffuse large B-cell non-Hodgkin's lymphoma, in a Kaposi's sarcoma (KS) cell line, and in healthy human umbilical vein ECs (HUVECs) following exposure to therapeutic doses of thalidomide. RESULTS: Thalidomide markedly downregulates the genes in a dose-dependent fashion in active MMECs and KS cell line, but upregulates them or is ineffective in nonactive MMECs, MG(u)ECs, NHL-ECs, and in HUVECs. Secretion of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and hepatocyte growth factor also diminishes according to the dose in culture conditioned media (CM) of active MMECs and KS, whereas it does not change in the other CM. CONCLUSION: Inhibition by thalidomide is probably confined to the genes of active MMECs and KS. This would account for its higher efficacy in these diseases.

Adult↗

PubMed2005

Statins activate the mitochondrial pathway of apoptosis in human lymphoblasts and myeloma cells.

Although statins are lipid-lowering drugs that block cholesterol biosynthesis, they exert immunomodulatory, anti-inflammatory, anti-angiogenic and anti-proliferative functions by reducing the isoprenylation of proteins involved in cell signal transduction such as Ras and RhoA. In this study, we provide evidence that several natural (lovastatin, simvastatin and pravastatin) and synthetic (cerivastatin and atorvastatin) statins exert a cytotoxic effect on human T, B and myeloma tumor cells by promoting their apoptosis. Dissimilar susceptibility to apoptosis has been detected in these lines, presumably in relation to the altered expression of proteins involved in the regulation of cellular signals. Cerivastatin promptly activated the cell death even in doxorubicin resistant cell lines such as MCC-2, whereas pravastatin, a hydrophilic compound, failed to induce any effect on either proliferation or apoptosis. The statin-induced apoptotic pathway in these cell lines was presumably regulated by altered prenylation of either Ras or RhoA, as measured by the defective membrane localization of these small GTPases. In addition the cell proliferation was rescued by both farnesylpyrophosphate (FPP) and geranyl-geranylpyrophosphate (GGPP), whereas no effect was obtained with squalene, a direct precursor of cholesterol. Statins primed apoptosis through its intrinsic pathway involving the mitochondria. In fact, we observed the reduction of mitochondrial membrane potential and the cytosolic release of the second mitochondria-derived activator of caspases (Smac/DIABLO). The apoptotic pathway was caspase-dependent since caspases 9, 3 and 8 were efficiently activated. These results support the potential use of statins in association with conventional treatment as apoptosis-triggering agents in these tumors.

Apoptosis↗

PubMed2005

HCV-associated B cell clonalities in the liver do not carry the t(14;18) chromosomal translocation.

Infection with HCV can be associated with B-cell non-Hodgkin lymphoma. Polymerase chain reaction (PCR) amplification assays for Bcl-2/IgH rearrangement were performed on nucleic acids extracted from portal tract inflammatory infiltrates, isolated with laser capture microdissection (LCM), from liver biopsy sections of 16 hepatitis C virus (HCV)-infected patients with and without extrahepatic B cell-related disorders. Results were compared with total DNA extracted from core liver biopsy specimens and from peripheral blood mononuclear cells (PBMCs). We failed to demonstrate specific Bcl-2/IgH amplicons either in liver tissue or in PBMCs in all patients of the current series. Multiple PCR assays for variable diversity joining (VDJ) IgH gene rearrangements were also performed in the liver compartment. Selective amplification compatible with mono or oligoclonal B cell clonotypes was demonstrated in 80% (6/8) and 25% (2/8) of patients with and without clinical evidence of B-cell disorders. V(H)1 and V(H)3 were the most represented V(H) families. In situ expression of Bcl-2 protein was carried out by immunohistochemistry on liver biopsy sections. Bcl-2 protein was detected in 2 (12.5%) patients who did not associate extrahepatic disorders. In conclusion, current data support the concept that production of IgH gene rearrangements is not associated with Bcl-2/IgH chromosomal translocation in hepatic compartment. Liver overexpression of Bcl-2 protein may occur in at least a minor proportion of HCV-infected patients.

Aged↗

PubMed2005

CD20: a target antigen for immunotherapy of autoimmune diseases.

This article reviews the role of CD20 antigen in B cell function and the effectiveness and limits of passive immunotherapy with anti-CD20 monoclonal antibody (Rituximab) in the treatment of autoimmune (or immune-mediated) diseases. Active immunotherapy is a more feasible way to control these chronic diseases. A peptide that mimics the CD20 epitope recognized by Rituximab is employed to stimulate the host immune response against CD20.

Animals↗

PubMed2005

Hepatitis C virus, cryoglobulinaemia, and vasculitis: immune complex relations.

Several viruses are involved in the development of systemic vasculitides. Hepatitis C virus (HCV) has been shown to be closely related to mixed cryoglobulinaemia, an immune complex-mediated vasculitis. HCV particles and non-enveloped nucleocapsid protein participate in the formation of immune complexes. Once formed, immune complexes precipitate in many organs, including the skin, kidneys, and peripheral nerve fibres. Viral proteins confer peculiar physical and chemical properties on cryoimmunoglobulins. Since expansion of rheumatoid factor-synthesising B cells is the biological hallmark of mixed cryoglobulinaemia, it may be that the combination of rheumatoid factor activity and cryoprecipitability is responsible for the vasculitis. B-cell clonal expansion occurs primarily in the liver and correlates with a high intrahepatic viral load, pointing to a major role for HCV in the emergence and maintenance of B-cell clonalities. Recognition of HCV as an aetiological factor in most cryoglobulinaemic vasculitides has dramatically changed the approach to their treatment. Emphasis, in fact, is now placed on abatement of the viral load and deletion of B-cell clonalities.

Antigen-Antibody Complex↗

PubMed2005

Functional osteoclast-like transformation of cultured human myeloma cell lines.

Hyperactive osteoclastogenesis is a hallmark of multiple myeloma, a B cell neoplasia homing to bone marrow and resulting in multiple osteolytic lesions and skeleton devastation. We provide evidence that myeloma cells can themselves act as osteoclasts in vitro. By extending standard cultures of U-266 and MCC-2 myeloma cell lines, we found that subsets of adherent cells also expressed the osteoclast phenotype, including multinuclear morphology, cytoplasmic tartrate-resistant acid phosphatase, the calcitonin receptor and a specific osteoclast antigen. These subsets resorbed bone substrates by producing osteoclast enzymes as well as the characteristic redistribution of F-actin in their cytoskeleton, thus forming the sealing zone that is adopted by adherent osteoclasts to generate the acidified environment essential for bone resorption. Neither the phenotype nor the functional properties of osteoclasts were detected in parental non-adherent cells. In adherent cultures osteoclastogenesis was associated with deregulated expression of both receptor activator of nuclear transcription factor (NF)-kappaB (RANK) and its ligand RANK-L, which triggers cell maturation in osteoclast precursors. Resorption of bone substrates was prevented by a neutralising anti-RANK-L antibody. Our data indicate that osteoclast-like transformation of both U-266 and MCC-2 cellular models of human myeloma is dependent on RANK-L stimulation.

Actins↗

PubMed2005

CD20 mimicry by a mAb rituximab-specific linear peptide: a potential tool for active immunotherapy of autoimmune diseases.

An attractive, whether alternative or complementary, approach to passive immunotherapy (IT) with the anti-CD20 mAb rituximab for the treatment of autoimmune diseases is to stimulate the host to produce an anti-CD20 immune response by using peptides that mimic CD20 (mimotopes). The only mimotope reported to target CD20 antigen is a 43-mer polypeptide corresponding to the exposed domain of the molecule (from amino acid 142 to 184). Owing to its length, however, it failed to efficiently induce a CD20-specific response. A search has now been made for a smaller mimotope by biopanning a phage-display peptide library with rituximab. A total of 10 positive phage clones expressing six distinct sequences were isolated. Their alignment produced a motif that did not match any portion of the CD20 extracellular loop, whereas the motif bearing the 12-mer linear peptide Rp10-L specifically reacted with rituximab and inhibited its binding to CD20. Furthermore, in BALB/c mice Rp10-L-induced antibodies that reacted with the CD20(+) B lymphoid cell line Raji but not with the C20(-) T lymphoid cell line CEM. This peptide is currently being investigated to determine the effectiveness of CD20-based active IT for the treatment of autoimmune diseases.

Amino Acid Sequence↗

PubMed2005

Antiangiogenesis for rheumatoid arthritis.

Angiogenesis, i.e., the induction of new blood vessels from existing vasculature, is a crucial event in the formation and maintenance of the pannus in rheumatoid arthritis (RA). The arthritis is characterized by destruction of peripheral joints in which the cartilage and bone are destroyed by proliferative synovitis. This is characterized by infiltration of inflammatory cells and formation of new blood vessels. Angiogenesis occurs since the early stage of the disease, and supports progression of the arthritis. It has been demonstrated in animal models of arthritis that inhibition of angiogenesis reduces of the arthritis. This suggests that pharmacological inhibition of angiogenesis may play an important role in the treatment of RA. In particular, disruption of new blood vessels can not only prevent delivery of nutrients to the inflammatory site, but can also lead to vessel regression, hence reversal of disease. To sum up, since angiogenesis is central in maintaining of synovitis in RA, antiangiogenesis probably represents a therapeutic tool. This view is supported by recent studies in animal models of arthritis where antiangiogenic drugs deliver a therapeutic benefit.

Angiogenesis Inhibitors↗

PubMed2004

Serum levels of angiogenic cytokines decrease after antineoplastic radiotherapy.

Serum levels of angiogenic cytokines decrease after radiotherapy in patients with cancer and their may have an impact on response to treatment and progression-free survival. Here, we have evaluated sera of patients before and after radiotherapy for various tumour types for levels of soluble fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) to assess whether these factors decrease after radiotherapy, and whether their diminution is related to the radiation dose, tumour type, age and haemoglobin level. We demonstrate that levels of FGF-2 and VEGF, but not HGF, decrease significantly, and that the extent of their diminution is related to the radiation dose and response.

Adult↗

PubMed2004

Intermediate-dose melphalan improves survival of myeloma patients aged 50 to 70: results of a randomized controlled trial.

High-dose therapy is an effective standard treatment for multiple myeloma patients. Evidence that intermediate-dose therapy improves survival is limited. At diagnosis, about 70% of patients are older than 65. Intermediate-dose regimen is very well tolerated in older patients. In a multicenter study, 194 patients were randomized to receive at diagnosis either conventional chemotherapy (6 courses of oral melphalan and prednisone [MP]) or intermediate-dose therapy (2 courses of melphalan at 100 mg/m(2) [MEL100]) with stem cell support. Response rate was higher after MEL100. Near-complete remission (nCR) was 6% after MP and 25% after MEL100 (P = .0002). At 3 years, MEL100 increased event-free survival (EFS) from 16% to 37% and overall survival (OS) from 62% to 77% (P < .001). Similar results were observed in patients aged 65 to 70: nCR was 8% after MP and 25% after MEL100 (P = .05); at 3 years, MEL100 improved EFS from 18% to 31% (P = .01) and OS from 58% to 73% (P = .01). Patients aged 65 to 70 had a median OS of 37.2 months (MP) versus 58 months (MEL100). Intermediate-dose melphalan improves response rate, EFS, and OS in myeloma patients, specifically in those aged 65 to 70. It constitutes a more effective first-line regimen than standard treatment for elderly patients.

Aged↗

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↗