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Perbellini R.,Molecular Cardiology Laboratory | Perbellini R.,University of Milan | Greco S.,Molecular Cardiology Laboratory | Sarra-Ferraris G.,Molecular Cardiology Laboratory | And 4 more authors.
Neuromuscular Disorders | Year: 2011

Myotonic Dystrophy Type-1 (DM1) is caused by the expansion of a CTG repeat with a peculiar pattern of multisystemic involvement affecting skeletal muscles, the heart, the eye, the central nervous system and the endocrine system. Since microRNA expression is disrupted in several myopathies, the expression of 24 candidate microRNAs was analyzed in skeletal muscle biopsies of 15 DM1 patients. Controls were constituted by biopsies without overt pathological features derived from 14 subjects with suspected neuromuscular disorder of undetermined nature. We found that miR-1 and miR-335 were up-regulated, whereas miR-29b and c, and miR-33 were down-regulated in DM1 biopsies compared to controls. We also found that the cellular distribution of muscle specific miR-1, miR-133b and miR-206 was severely altered in DM1 skeletal muscles. MicroRNA dysregulation was likely functionally relevant, since it impacted on the expression of the predicted miR-1, and miR-29 targets. The observed miRNA dysregulations and myslocalizations may contribute to DM1 pathogenetic mechanisms. © 2010 Elsevier B.V.

Aguzzi M.S.,Laboratorio Patologia Vascolare | D'Arcangelo D.,Laboratorio Patologia Vascolare | Giampietri C.,University of Rome La Sapienza | Capogrossi M.C.,Laboratorio Patologia Vascolare | Facchiano A.,Laboratorio Patologia Vascolare
PLoS ONE | Year: 2011

Peptides containing the RGD sequence are under continuous investigation given their ability to control cell adhesion and apoptosis. Since small peptides are quickly metabolized and degraded in vivo, developing analogs resistant to serum-induced degradation is a challenging task. RGD analogs developed so far are known as molecules mostly inhibiting cell adhesion; this feature may reduce cell proliferation and tumor development but may not induce regression of tumors or metastases already formed. In the current study, carried out in melanoma in vitro and in vivo models, we show that RAM, an RGD-non-peptide Analog-Molecule, strongly inhibits cells adhesion onto plastic, vitronectin, fibronectin, laminin and von Willebrand Factor while it does not inhibit cell adhesion onto collagen IV, similarly to the RGDS template peptide. It also strongly inhibits in vitro cell proliferation, migration and DNA-synthesis, increases melanoma cells apoptosis and reduces survivin expression. All such effects were observed in collagen IV seeded cells, therefore are most likely independent from the anti adhesive properties. Further, RAM is more stable than the template RGDS; in fact it maintains its anti-proliferation and anti-adhesion effects after long serum exposure while RGDS almost completely loses its effects upon serum exposure. In a mouse metastatic melanoma in vivo model, increasing doses of RAM significantly reduce up to about 80% lung metastases development, while comparable doses of RGDS are less potent. In conclusion these data show that RAM is a potent inhibitor of melanoma growth in vitro, strongly reduces melanoma metastases development in vivo and represents a novel candidate for further in vivo investigations in the cancer treatment field. © 2011 Aguzzi et al.

Aguzzi M.S.,Laboratorio Patologia Vascolare | Fortugno P.,Laboratorio Biologia Molecolare e Cellulare | Giampietri C.,University of Rome La Sapienza | Ragone G.,Laboratorio Oncogenesi Molecolare | And 2 more authors.
Molecular Cancer | Year: 2010

Background: RGD-motif acts as a specific integrins-ligand and regulates a variety of cell-functions via extracellular action affecting cell-adhesion properties. However, increasing evidence identifies additional RGDS-functions at intracellular level. Previous reports show RGDS-internalization in endothelial cells, cardiomyocytes and lymphocytes, indicating intracellular targets such as caspase-8 and caspase-9, and suggest RGDS specific activity at cytoplasmic level. Given the role RGDS-peptides play in controlling proliferation and apoptosis in several cell types, investigating intracellular targets of RGDS in melanoma cells may un-reveal novel molecular targets and key pathways, potentially useful for a more effective approach to melanoma treatment.Results: In the present study we show for the first time that RGDS-peptide is internalized in melanoma cells in a time-dependent way and exerts strong anti-proliferative and pro-apoptotic effects independently from its extracellular anti-adhesive action. RGES control-peptide did not show biological effects, as expected; nevertheless it is internalized, although with slower kinetics. Survivin, a known cell-cycle and survival-regulator is highly expressed in melanoma cells. Co-immunoprecipitation assays in cell lysates and overlay assays with the purified proteins showed that RGDS interacts with survivin, as well as with procaspase-3, -8 and -9. RGDS-peptide binding to survivin was found to be specific, at high affinity (Kd 27.5 μM) and located at the survivin C-terminus. RGDS-survivin interaction appeared to play a key role, since RGDS lost its anti-mitogenic effect in survivin-deprived cells with a specific siRNA.Conclusions: RGDS inhibits melanoma growth with an adhesion-independent mechanism; it is internalized in melanoma cells and specifically interacts with survivin. The present data may indicate a novel role of RGDS-containing peptides physiologically released from the extracellular matrix and may suggest a possible novel anti-proliferation strategy in melanoma. © 2010 Aguzzi et al; licensee BioMed Central Ltd.

Aguzzi M.S.,Laboratorio Patologia Vascolare | Faraone D.,Laboratorio Patologia Vascolare | D'Arcangelo D.,Laboratorio Patologia Vascolare | De Marchis F.,Laboratorio Patologia Vascolare | And 5 more authors.
Molecular Therapy | Year: 2011

Previous data report that fibroblast growth factor-2 (FGF-2)-derived peptide FREG potently inhibits FGF-2-dependent angiogenesis in vitro and in vivo. Here, we show that FREG inhibits up to 70% in vitro growth and invasion/migration of smooth muscle and melanoma cells. Such inhibition is mediated by platelet-derived growth factor-receptor-α (PDGF-Rα); in fact, proliferation and migration were restored upon PDGF-Rα neutralization. Further experiments demonstrated that FREG interacts with PDGF-Rα both in vitro and in vivo and stimulates its phosphorylation. We have previously shown that overexpressing PDGF-Rα strongly inhibits melanoma growth in vivo; we, therefore, hypothesized that PDGF-Rα agonists may represent a novel tool to inhibit melanoma growth in vivo. To support this hypothesis, FREG was inoculated intravenously (i.v.) in a mouse melanoma model and markedly inhibited pulmonary metastases formation. Immunohistochemical analyses showed less proliferation, less angiogenesis, and more apoptosis in metastasized lungs upon FREG treatment, as compared to untreated controls. Finally, in preliminary acute toxicity studies, FREG showed no toxicity signs in healthy animals, and neither microscopic nor macroscopic toxicity at the liver, kidney, and lungs level. Altogether, these data indicate that FREG systemic treatment strongly inhibits melanoma metastases development and indicate for the first time that agonists of PDGF-Rα may control melanoma both in vitro and in vivo. © The American Society of Gene & Cell Therapy.

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