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D'Alessio A.,Cell Biology and Biotherapy Unit | De Luca A.,Cell Biology and Biotherapy Unit | Maiello M.R.,Cell Biology and Biotherapy Unit | Lamura L.,Cell Biology and Biotherapy Unit | And 4 more authors.
Breast Cancer Research and Treatment | Year: 2010

Treatment of breast cancer cells with a combination of the EGFR-tyrosine kinase inhibitor (EGFR-TKI) gefitinib and the anti-ErbB-2 monoclonal antibody trastuzumab results in a synergistic antitumor effect. In this study, we addressed the mechanisms involved in this phenomenon. The activation of signaling pathways and the expression of cell cycle regulatory proteins were studied in SK-Br-3 and BT-474 breast cancer cells, following treatment with EGFR and/or ErbB-2 inhibitors. Treatment with the gefitinib/trastuzumab combination produced, as compared with a single agent, a more prolonged blockade of AKT and MAPK activation, a more pronounced accumulation of cells in the G0/G1 phase of the cell cycle, a more significant increase in the levels of p27kip1 and of hypophosphorylated pRb2, and a decrease in the levels of Cyclin D1 and survivin. Similar findings were observed with the EGFR/ErbB-2 inhibitor lapatinib. Gefitinib, trastuzumab, and their combination increased the stability of p27kip1, with the combination showing the highest effects. Blockade of both receptors with gefitinib/trastuzumab or lapatinib induced a significant increase in the levels of p27kip1 mRNA and in the nuclear levels of the p27kip1 transcription factor FKHRL-1. Inhibition of PI3K signaling also produced a significant raise in p27kip1 mRNA. Finally, down-modulation of FKHRL-1 with siRNAs prevented the lapatinib-induced increase of p27kip1 mRNA. The synergism deriving from EGFR and ErbB-2 blockade is mediated by several different alterations in the activation of signaling proteins and in the expression of cell cycle regulatory proteins, including transcriptional and posttranscriptional regulation of p27 kip1 expression. © 2009 Springer Science+Business Media, LLC.

Accardo A.,University of Naples Federico II | Galli F.,University of Rome La Sapienza | Mansi R.,University Hospital Freiburg | Del Pozzo L.,University Hospital Freiburg | And 6 more authors.
EJNMMI Research | Year: 2016

Background: Overexpression of the gastrin-releasing peptide receptor (GRP-R) has been documented in several human neoplasms such as breast, prostate, and ovarian cancer. There is growing interest in developing radiolabeled peptide-based ligands toward these receptors for the purpose of in vivo imaging and radionuclide therapy of GRP-R-overexpressing tumors. A number of different peptide sequences, isotopes, and labeling methods have been proposed for this purpose. The aim of this work is to perform a direct side-by-side comparison of different GRP-R binding peptides utilizing a single labeling strategy to identify the most suitable peptide sequence. Methods: Solid-phase synthesis of eight derivatives (BN1-8) designed based on literature analysis was carried out. Peptides were coupled to the DOTA chelator through a PEG4 spacer at the N-terminus. Derivatives were characterized for serum stability, binding affinity on PC-3 human prostate cancer cells, biodistribution in tumor-bearing mice, and gamma camera imaging at 1, 6, and 24 h after injection. Results: Serum stability was quite variable among the different compounds with half-lives ranging from 16 to 400 min at 37 °C. All compounds tested showed Kd values in the nanomolar range with the exception of BN3 that showed no binding. Biodistribution and imaging studies carried out for compounds BN1, BN4, BN7, and BN8 showed targeting of the GRP-R-positive tumors and the pancreas. The BN8 compound (DOTA-PEG-DPhe-Gln-Trp-Ala-Val-NMeGly-His-Sta-Leu-NH2) showed high affinity, the longest serum stability, and the highest target-to-background ratios in biodistribution and imaging experiments among the compounds tested. Conclusions: Our results indicate that the NMeGly for Gly substitution and the Sta-Leu substitution at the C-terminus confer high serum stability while maintaining high receptor affinity, resulting in biodistribution properties that outperform those of the other peptides. © 2016, Accardo et al.

Di Bernardo G.,The Second University of Naples | Galderisi U.,The Second University of Naples | Galderisi U.,Temple University | Fiorito C.,IRCCS MultiMedica | And 8 more authors.
Journal of Cellular Physiology | Year: 2010

Hematopoietic stem cells derive regulatory information also from parathyroid hormone (PTH). To explore the possibility that PTH may have a role in regulation of other stem cells residing in bone marrow, such as mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) we assessed the effect of this hormone on the in vitro behavior of MSCs and EPCs. Weevidenced that MSCs were much more responsive to PTH than EPCs. PTH increased the proliferation rate of MSCs with a diminution of senescence and apoptosis. Taken together, our results may suggest a protective effect of PTH on MSCs that reduces stress phenomena and preserve genome integrity. At the opposite, PTH did not modify the fate of EPCs in culture. © 2009 Wiley-Liss, Inc.

Evangelista D.,Centro Ricerche Oncologiche Mercogliano | Evangelista D.,University of Naples Federico II | Colonna G.,The Second University of Naples | Miele M.,Centro Ricerche Oncologiche Mercogliano | And 5 more authors.
Protein Engineering, Design and Selection | Year: 2010

The cytokines, main players of the chronic inflammation progression leading to serious diseases such as diabetes or cancer, represent a target for better clinical prognosis and innovative therapeutic strategies. To investigate the immunopathogenetic progression of these diseases, the evaluation of serum cytokines profiles made of many different proteins is much more informative than single protein measurements. We developed a Clinical Data Mining Software to collect cytokine profiles evaluated on healthy subjects and patients by multiplex immunoassays also annotated with their clinical and laboratory data, to compare patient profiles by statistical tools and to evaluate their disease progression. © The Author 2010. Published by Oxford University Press. All rights reserved.

Bizzarro V.,University of Salerno | Belvedere R.,University of Salerno | Milone M.R.,Centro Ricerche Oncologiche Mercogliano | Pucci B.,Centro Ricerche Oncologiche Mercogliano | And 7 more authors.
Oncotarget | Year: 2015

In this study, we have characterized the role of annexin A1 (ANXA1) in the acquisition and maintenance of stem-like/aggressive features in prostate cancer (PCa) cells comparing zoledronic acid (ZA)-resistant DU145R80 with their parental DU145 cells. ANXA1 is over-expressed in DU145R80 cells and its down-regulation abolishes their resistance to ZA. Moreover, ANXA1 induces DU145 and DU145R80 invasiveness acting through formyl peptide receptors (FPRs). Also, ANXA1 knockdown is able to inhibit epithelial to mesenchymal transition (EMT) and to reduce focal adhesion kinase (FAK) and metalloproteases (MMP)-2/9 expression in PCa cells. DU145R80 show a cancer stem cell (CSC)-like signature with a high expression of CSC markers including CD44, CD133, NANOG, Snail, Oct4 and ALDH7A1 and CSC-related genes as STAT3. Interestingly, ANXA1 knockdown induces these cells to revert from a putative prostate CSC to a more differentiated phenotype resembling DU145 PCa cell signature. Similar results are obtained concerning some drug resistance-related genes such as ATP Binding Cassette G2 (ABCG2) and Lung Resistant Protein (LRP). Our study provides new insights on the role of ANXA1 protein in PCa onset and progression.

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