Biomedical subjects

Claudia Curcio

Publications and source records attributed to Claudia Curcio.

13 recordsLinked to original sources

PubMed2006

WIP regulates the stability and localization of WASP to podosomes in migrating dendritic cells.

The Wiskott-Aldrich Syndrome protein (WASP) is an adaptor protein that is essential for podosome formation in hematopoietic cells. Given that 80% of identified Wiskott-Aldrich Syndrome patients result from mutations in the binding site for WASP-interacting-protein (WIP), we examined the possible role of WIP in the regulation of podosome architecture and cell motility in dendritic cells (DCs). Our results show that WIP is essential both for the formation of actin cores containing WASP and cortactin and for the organization of integrin and integrin-associated proteins in circular arrays, specific characteristics of podosome structure. We also found that WIP is essential for the maintenance of the high turnover of adhesions and polarity in DCs. WIP exerts these functions by regulating calpain-mediated cleavage of WASP and by facilitating the localization of WASP to sites of actin polymerization at podosomes. Taken together, our results indicate that WIP is critical for the regulation of both the stability and localization of WASP in migrating DCs and suggest that WASP and WIP operate as a functional unit to control DC motility in response to changes in the extracellular environment.

Actins↗

PubMed2006

A role for WASP Interacting Protein, WIP, in fibroblast adhesion, spreading and migration.

The WASP (Wiskott Aldrich Syndrome Protein) Interacting Protein, WIP, regulates actin polymerization and the formation of actin-rich structures such as filopodia and lamellipodia, each of which is involved in cellular adhesion, spreading and migration. To define the role for WIP in these activities, we analysed cell adhesion and spreading as well as the redistribution of polymerised actin and paxillin that occurred when fibroblasts were plated onto different substrata. We compared the effect of WIP overexpression (gain of function) with that of WIP deficiency (loss of function) on these parameters. WIP-overexpression delayed cellular adhesion and spreading, an effect that could be compensated for by exposure to Y-27632, a well characterized ROCK (Rho kinase) inhibitor. WIP overexpression augmented the phosphorylation of Erk and JNK induced by binding to fibronectin, suggesting that WIP participates in signal transduction pathways initiated by integrin engagement. Conversely, WIP deficiency accelerated fibroblast adhesion to plastic and led to the formation of enlarged focal adhesions. The influence of WIP on fibroblast migration was measured by scratch assay. WIP-overexpression reduced migration while WIP-deficiency increased it, suggesting that WIP acts as a negative regulator of fibroblast migration. Together, these findings suggest a novel role for WIP in fibroblast adhesion, spreading and migration.

Amides↗

PubMed2006

Immunosurveillance of Erbb2 carcinogenesis in transgenic mice is concealed by a dominant regulatory T-cell self-tolerance.

To assess the role of CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells in overcoming immunosurveillance of Erbb2 (HER-2/neu) mammary lesions, we studied the effects of their sustained removal in BALB/c female mice made transgenic for the rat Erbb2 (r-Erbb2) oncogene (BALB-neuT mice), which develop multiple mammary carcinomas. During the progression of these lesions, Treg cells expand in the spleen, tumor draining lymph nodes, and tumors. Repeated administration of anti-CD25 antibodies extends tumor-free survival, reduces carcinoma multiplicity, and leads to the manifestation of a natural antibody and CTL-mediated reactivity against r-Erbb2. Loss of Foxp3(+) Treg cells during anti-CD25 treatment remarkably caused the disappearance of Gr1(+) immature myeloid cells, suggesting a cross-talk between these two inhibitory immune cell types. Treg cell expansion associated with r-Erbb2 overexpression may be seen as a physiologic response to dampen the immune reaction elicited by local anomalous overexpression of a self-antigen.

Animals↗

PubMed2006

A DNA vaccine targeting angiomotin inhibits angiogenesis and suppresses tumor growth.

Endogenous angiogenesis inhibitors have shown promise in preclinical trials, but clinical use has been hindered by low half-life in circulation and high production costs. Here, we describe a strategy that targets the angiostatin receptor angiomotin (Amot) by DNA vaccination. The vaccination procedure generated antibodies that detected Amot on the endothelial cell surface. Purified Ig bound to the endothelial cell membrane and inhibited endothelial cell migration. In vivo, DNA vaccination blocked angiogenesis in the matrigel plug assay and prevented growth of transplanted tumors for up to 150 days. We further demonstrate that a combination of DNA vaccines encoding Amot and the extracellular and transmembrane domains of the human EGF receptor 2 (Her-2)/neu oncogene inhibited breast cancer progression and impaired tumor vascularization in Her-2/neu transgenic mice. No toxicity or impairment of normal blood vessels could be detected. This work shows that DNA vaccination targeting Amot may be used to mimic the effect of angiostatin.

Angiomotins↗

PubMed2005

A single vaccination with polyomavirus VP1/VP2Her2 virus-like particles prevents outgrowth of HER-2/neu-expressing tumors.

Murine polyomavirus (MPyV) VP1 virus-like particles (VLPs), containing a fusion protein between MPyV VP2 and the extracellular and transmembrane domain of HER-2/neu (Her2), Her2(1-683)PyVLPs, were tested for their ability to vaccinate against Her2-expressing tumors in two different in vivo models. Protection was assessed both against a lethal challenge with a BALB/c mammary carcinoma transfected with human Her2 (D2F2/E2) and against the outgrowth of autochthonous mammary carcinomas in BALB-neuT mice, transgenic for the activated rat Her2 oncogene. A single injection of Her2(1-683)PyVLPs before tumor inoculation induced a complete rejection of D2F2/E2 tumor cells in BALB/c mice. Similarly, a single injection of Her2(1-683)PyVLPs at 6 weeks of age protected BALB-neuT mice with atypical hyperplasia from a later outgrowth of mammary carcinomas, whereas all controls developed palpable tumors in all mammary glands. VLPs containing only VP1 and VP2 did not induce protection. The protection elicited by Her2(1-683)PyVLPs vaccination was most likely due to a cellular immune response because a Her2-specific response was shown in an ELISPOT assay, whereas antibodies against Her2 were not detected in any of the two models. The results show the feasibility of using MPyV-VLPs carrying Her2 fusion proteins as safe and efficient vaccines against Her2-expressing tumors.

Animals↗

PubMed2005

Cure of mammary carcinomas in Her-2 transgenic mice through sequential stimulation of innate (neoadjuvant interleukin-12) and adaptive (DNA vaccine electroporation) immunity.

PURPOSE: Whereas neoadjuvant therapy is emerging as a treatment option in early primary breast cancer, no data are available on the use of antiangiogenic and immunomodulatory agents in a neoadjuvant setting. In a model of Her-2 spontaneous mammary cancer, we investigated the efficacy of neoadjuvant interleukin 12 (IL-12) followed by "immune-surgery" of the residual tumor. EXPERIMENTAL DESIGN: Female BALB/c mice transgenic for the rat Her-2 oncogene inexorably develop invasive carcinomas in all their mammary glands by the 23rd week of age. Mice with multifocal in situ carcinomas received four weekly i.p. injections of 100 ng IL-12 followed by a 3-week rest. This course was given four times. A few mice additionally received DNA plasmids encoding portions of the Her-2 receptor electroporated through transcutaneous electric pulses. RESULTS: The protection elicited by IL-12 in combination with two DNA vaccine electroporations kept 63% of mice tumor-free. Complete protection of all 1-year-old mice was achieved when IL-12-treated mice received four vaccine electroporations. Pathologic findings, in vitro tests, and the results from immunization of both IFN-gamma and immunoglobulin gene knockout transgenic mice and of adoptive transfer experiments all show that IL-12 augments the B- and T-cell response elicited by vaccination and slightly decreases the number of regulatory T cells. In addition, IL-12 strongly inhibits tumor angiogenesis. CONCLUSIONS: In Her-2 transgenic mice, IL-12 impairs tumor progression and triggers innate immunity so markedly that DNA vaccination becomes effective at late points in time when it is ineffective on its own.

Animals↗

PubMed2005

Immunotherapy and immunoprevention of cancer: where do we stand?

Although evolution has shaped the immune system to control microbial invasions, this does not necessarily mean that the immune system can not be triggered to eliminate tumour cells. The exploitation of the terrific potential of the immune system to recognise cell alterations and to selectively destroy large populations of neoplastic cells is a possibility made even more attractive by the advances in our understanding of the immune mechanisms and our ability to manipulate them. This review summarises the state of the different immunotherapy strategies available or in development today, and examines the future developments that hold out the promise of an effective control of cancer growth.

Animals↗

PubMed2004

Oral lactoferrin inhibits growth of established tumors and potentiates conventional chemotherapy.

In this work, we investigated the anticancer activity of orally administered recombinant human lactoferrin (rhLF) alone and in combination with chemotherapy in tumor-bearing mice. rhLF inhibited the growth of squamous cell carcinoma (O12) tumors in T cell-immunocompromised nu/nu mice by 80% when administered at 1,000 mg/kg (2.9 g/m2) by oral gavage twice daily for 8 days (p < 0.001). Similar activity was observed in syngeneic, immunocompetent BALB/c mice, where orally administered rhLF (1,000 mg/kg, 2.9 g/m2 once daily) halted the growth of mammary adenocarcinoma TUBO. Oral rhLF (200 mg/kg, 0.57 g/m2) was also used alone and in combination with cis-platinum (5 mg/kg) to treat head-and-neck squamous cell carcinoma in a syngeneic murine model. Monotherapy with oral rhLF or cis-platinum caused 61% or 66% tumor growth inhibition over placebo, respectively. Mice receiving both therapies showed 79% growth inhibition, a statistically significant improvement over each drug alone. We then demonstrated that administration of oral rhLF (300 mg/kg, 0.86 g/m2) to tumor-bearing or naive mice resulted in (i) significantly increased production of IL-18 in the intestinal tract, (ii) systemic NK cell activation and (iii) circulating CD8+ T-cell expansion. These data suggest that oral rhLF is an immunomodulatory agent active against cancer as a single agent and in combination chemotherapy, exerting its systemic effect through stimulation of IL-18 and other cytokines in the gut enterocytes. rhLF has been administered orally to 211 people without a single serious drug-related adverse event. Thus, rhLF shows promise as a safe and well-tolerated novel immunomodulatory anticancer agent.

Administration, Oral↗

PubMed2004

Electroporated DNA vaccine clears away multifocal mammary carcinomas in her-2/neu transgenic mice.

The transforming rat Her-2/neu oncogene embedded into the genome of virgin transgenic BALB/c mice (BALB-neuT) provokes the development of an invasive carcinoma in each of their 10 mammary glands. i.m. vaccination with DNA plasmids coding for the extracellular and transmembrane domains of the protein product of the Her-2/neu oncogene started when mice already display multifocal in situ carcinomas temporarily halts neoplastic progression, but all mice develop a tumor by week 43. By contrast, progressive clearance of neoplastic lesions and complete protection of all 1-year-old mice are achieved when the same plasmids are electroporated at 10-week intervals. Pathological findings, in vitro tests, and the results from the immunization of both IFN-gamma and immunoglobulin gene knockout BALB-neuT mice, and of adoptive transfer experiments, all suggest that tumor clearance rests on the combination of antibodies and IFN-gamma-releasing T cells. These findings show that an appropriate vaccine effectively inhibits the progression of multifocal preneoplastic lesions.

Animals↗

PubMed2004

Immunological inhibition of carcinogenesis.

The combination of new information provided by fundamental immunology, along with the refinement of genetic engineering techniques has given scientists the capacity to produce vaccines able to inhibit the growth of most if not every transplantable tumor. However, when faced with already established tumors, vaccines fail to afford any significant protection. Many studies are underway which seek to overcome this gloomy situation. However, another possibility is to follow the indications provided by a large quantity of experimental data and to evaluate the possibility of using immunotherapy to prevent the initial stages of tumor growth. Is it possible to prevent an autologous tumor by means of a vaccination performed before tumor onset? Could antitumor vaccines be a new form of preventive medicine in the wake of Jenner, Pasteur, and other pioneers? In this paper it is our intention to review the results obtained by our laboratory in the attempt to use natural and adaptive immunity in the control of carcinogenesis. Natural immunity boosted by IL-12 and IL-2 significantly hampers the progression of mammary lesions occurring in HER-2/neu transgenic mice genetically predestined to develop lethal mammary carcinomas. Specific immunity elicited by DNA vaccination provides a much stronger inhibition of the development of mammary lesions, and a significant number of transgenic mice are tumor free at 1 year of age. These experimental data suggest the possibility of using immunity as a means of controlling preneoplastic lesions and protecting healthy persons at risk of developing cancer.

Animals↗

PubMed2003

WIP participates in actin reorganization and ruffle formation induced by PDGF.

Platelet-derived growth factor (PDGF) is a chemotactic factor for fibroblasts that triggers actin cytoskeleton reorganization by increasing the level of GTP-Rac, the activated form of a small Rho family GTPase. GTP-Rac induces membrane ruffling and lamellipodium formation that are required for adhesion, migration and macropinocytosis, among other functions. We have shown that WIP interacts with members of the Wiskott-Aldrich syndrome protein family and is essential for filopodium formation regulated by Cdc42 GTPase. In this report, we show that WIP participates in the actin reorganization that leads to ruffle formation. WIP overexpression in murine fibroblasts (3T3 cells) enhances ruffle formation in response to PDGF stimulation, as shown by immunofluorescence and electron and video microscopy. More importantly, microinjection of anti-WIP antibody or absence of WIP in murine fibroblasts results in decreased ruffle formation in response to PDGF treatment. Finally, overexpression of a modified form of WIP lacking the actin-binding site blocks PDGF-induced membrane ruffling. These data suggest a role for WIP in actin reorganization to form PDGF-induced ruffles. This is the first in vivo evidence in mammalian cells for a function of WIP dependent on its ability to bind actin.

Actin Cytoskeleton↗

PubMed2003

Immunization in tumor prevention.

Recent experimental data suggest that immunity can be activated to prevent tumors. The rationale for prevention is strong because the setting is one endowed with an immune system that is neither impaired by tumor and treatment-induced suppression, nor tolerant to tumor-associated antigens. Oncogenic growth factor receptors are tumor antigens and rational targets for specific immunoprevention. Successful prevention of mammary carcinomas in Her-2/neu transgenic mice is cited as an evidence of the validity of this approach. The specific properties of the Her-2/neu gene product as an antigen and the nature of the immune responses induced by effective preventive treatments are summarized.

Animals↗

PubMed2003

Nonredundant roles of antibody, cytokines, and perforin in the eradication of established Her-2/neu carcinomas.

Since the mechanisms by which specific immunity destroys Her-2/neu carcinoma cells are highly undetermined, these were assessed in BALB/c mice vaccinated with plasmids encoding extracellular and transmembrane domains of the protein product (p185(neu)) of the rat Her-2/neu oncogene shot into the skin by gene gun. Vaccinated mice rejected a lethal challenge of TUBO carcinoma cells expressing p185(neu). Depletion of CD4 T cells during immunization abolished the protection, while depletion of CD8 cells during the effector phase halved it, and depletion of polymorphonuclear granulocytes abolished all protection. By contrast, Ig mu-chain gene KO mice, as well as Fcgamma receptor I/III, beta-2 microglobulin, CD1, monocyte chemoattractant protein 1 (MCP1), IFN-gamma, and perforin gene KO mice were protected. Only mice with both IFN-gamma and perforin gene KOs were not protected. Although immunization also cured all BALB/c mice bearing established TUBO carcinomas, it did not cure any of the perforin KO or perforin and IFN-gamma KO mice. Few mice were cured that had knockouts of the gene for Ig mu-chain, Fcgamma receptor I/III, IFN-gamma, or beta-2 microglobulin. Moreover, vaccination cured half of the CD1 and the majority of the MCP1 KO mice. The eradication of established p185(neu) carcinomas involves distinct mechanisms, each endowed with a different curative potential.

Animals↗