[Show abstract][Hide abstract] ABSTRACT: Conventional melanoma serum biomarkers (S100 and lactate dehydrogenase [LDH]) perform poorly in patients with uveal melanoma, and the search for new biomarkers is needed. A high expression of the oncoprotein c-Met in primary uveal melanoma is associated with metastatic progression, and c-Met is released as a soluble ectodomain through ADAM10- and ADAM17-mediated cleavage, suggesting a possible role as biomarker.
To determine the potential role of soluble c-Met (sc-Met) as a biomarker of uveal melanoma progression in comparison with S100 and LDH.
Soluble c-Met was studied in the conditioned medium of 9 uveal melanoma cell lines and in the blood serum samples of 24 mice with uveal melanoma xenografts, 57 patients with uveal melanoma (17 patients whose tumors metastasized and 40 patients whose tumors did not metastasize), and 37 healthy donors. We collected blood samples for as long as 5 years after treatment of the primary tumor. The concentration of sc-Met was measured using enzyme-linked immunosorbent assays, and the receiver operating characteristic curve was used to evaluate sensitivity and specificity in the identification of metastatic uveal melanoma. The study began on May 2, 2011, and the last samples were collected in January 2015.
Levels of sc-Met in uveal melanoma cell cultures and in the blood serum samples of xenotransplanted mice, of healthy donors, and of patients with uveal melanoma during follow-up.
The conditioned medium of uveal melanoma cell lines and the blood serum samples of mice with uveal melanoma xenografts contained significant levels of sc-Met. Patients with metastatic disease had significantly higher serum levels of sc-Met (median level, 590 ng/mL [range, 246-12 856 ng/mL]) than did patients without metastatic disease (median level, 296 ng/mL [range, 201-469 ng/mL]) (P < .001) and healthy donors (median level, 285 ng/mL [range 65-463 ng/mL]) (P < .001). Analysis of receiver operating characteristic curves for sc-Met levels in patients with nonmetastatic uveal melanoma vs patients with metastatic uveal melanoma yielded an area under the curve of 0.82 (95% CI, 0.68-0.95) (P < .001), which was superior to the areas under the curve achieved with S100 or LDH markers. Patients with progressive metastatic disease showed further increases in sc-Met level, whereas stable patients did not.
The present pilot study suggests that sc-Met should be further exploited as a biomarker for monitoring of uveal melanoma.
No preview · Article · Jun 2015 · Jama Ophthalmology
[Show abstract][Hide abstract] ABSTRACT: The standard of care for advanced non-small cell lung cancer (NSCLC) consists in cisplatin-combination chemotherapy. In patients bearing tumors with activating mutations of the epidermal growth factor receptor (EGFR), the inhibition of the EGFR intracellular tyrosine kinase can induce up to 80 % response rates. However, both therapeutic strategies will eventually lead to recurrent disease due to the development of drug resistance. The identification of rare cancer stem-like cells able to repopulate the tumor, after failure to standard treatment modalities, has led to characterize these cells as potential therapeutic targets. This article will address the role of the CD133/EpCAM stem cell-related markers and explore cell sensitivity to cisplatin and to the EGFR-tyrosine kinase inhibitor, afatinib. Three human NSCLC cell lines, one wild-type (A549) and two harboring EGFR mutations (H1650 and H1975), as well as 20 NSCLC primary cultures, were grown in non-differentiating culture conditions for stem cell enrichment. Flow-cytometry analyses of CD133 and EpCAM and cell sensitivity to cisplatin and afatinib were performed. Moreover, the expression of activated EGFR was assessed by Western blot. The cell lines and primary cultures grown in non-differentiating culture conditions were enriched with CD133/EpCAM-positive cells and were significantly more resistant to cisplatin and more sensitive to afatinib as compared to the differentiated counterpart. In addition, increased EGFR-phosphorylation in non-differentiated cultures was observed. The present findings suggest that afatinib might be beneficial for patients bearing tumors with constitutively activated EGFR, to target chemo-resistant CD133/EpCAM-positive cancer stem cells.
Full-text · Article · Feb 2015 · Archivum Immunologiae et Therapiae Experimentalis
[Show abstract][Hide abstract] ABSTRACT: Folic acid has emerged as an interesting cell-targeting moiety and a number of drugs have been conjugated to folate. In this context, new conjugates of β-cyclodextrins with folate have been synthesised as drug carriers to improve their selectivity for cells overexpressing the folic acid receptor. In particular, both 3- and 6-functionalised β-cyclodextrins, linked to the α- or γ-carboxylic group of folic acid, have been synthesised and fully characterised. As a proof of concept, the antitumour platinum(IV) complex cis–trans–cis-[PtCl2(CH3CO2)2(adamantylamine)(NH3)] (LA-12) has been used as a guest drug. The LA-12–cyclodextrin inclusion complexes have been tested on tumour cells. In the presence of cyclodextrin–folate conjugates, LA-12 exhibited IC50 values four times smaller than those of LA-12 alone in MDA-MB-231 cells, which overexpress folic acid receptors on their membrane. No improvement of LA-12 cytotoxicity was found in control tumour cells that do not overexpress the folate receptor. Thus, the non-covalent approach, based on inclusion complexes with functionalised cyclodextrins, looks very promising for drug targeting.
[Show abstract][Hide abstract] ABSTRACT: Uveal melanoma (UM) is a rare ocular tumor that may lead to deadly metastases in 50% of patients. ADAM (a disintegrin and metalloproteinase)10, ADAM17 and the HGF receptor c-Met support invasiveness in different tumors. Here, we report that high ADAM10, MET and, to a lesser extent, ADAM17 gene expression correlate with poor progression-free survival in UM patients (hazard ratio 2.7, 2.6 and 1.9, respectively). About 60% of primary UM express c-Met and/or ADAM10 proteins. Four UM cell lines display high levels of ADAM10 and ADAM17, which constitutively cleave c-Met, inducing the release of soluble c-Met. ADAM10/17 pharmacological inhibition or gene silencing reduces c-Met shedding, but has limited impact on surface c-Met, which is overexpressed. Importantly, ADAM10 silencing inhibits UM cell invasion driven by FCS or HGF, while ADAM17 silencing has a limited effect. Altogether our data indicate that ADAM10 has a pro-invasive role and may contribute to UM progression.This article is protected by copyright. All rights reserved.
No preview · Article · Aug 2014 · Pigment Cell & Melanoma Research
[Show abstract][Hide abstract] ABSTRACT: Some new N-[6-indazolyl]arylsulfonamides and N-[alkoxy-6-indazolyl]arylsulfonamides were prepared by the reduction of 2-alkyl-6-nitroindazoles with SnCl2 in different alcohols, followed by coupling the corresponding amine with arylsulfonyl chlorides in pyridine. The newly synthesized compounds were evaluated for their antiproliferative and apoptotic activities against two human tumor cell lines: A2780 (ovarian carcinoma) and A549 (lung adenocarcinoma). Preliminary in vitro pharmacological studies revealed that N-(2-allyl-2H-indazol-6-yl)-4-methoxybenzenesulfonamide 4 and N-[7-ethoxy-2-(4-methyl-benzyl)-2H-indazol-6-yl]-4-methyl-benzenesulfonamide 9 exhibited significant antiproliferative activity against the A2780 and A549 cell lines with IC50 values in the range from 4.21 to 18.6 µM, and also that they trigger apoptosis in a dose-dependent manner. Furthermore, both active compounds were able to cause an arrest of cells in the G2/M phase of the cell cycle, typical but not exclusive of tubulin interacting agents, although only infrequent interactions with the microtubule network were observed by immunofluorescence microscopy, while docking analysis showed a possible different behavior between the two active compounds.
No preview · Article · Jun 2014 · Archiv der Pharmazie
[Show abstract][Hide abstract] ABSTRACT: Docking methods are powerful tools for in silico screening and drug lead generation and optimization. Here, we describe the synthesis of new inhibitors of ABCB1 whose design was based on construction and preliminary confirmation of a model for this membrane transporter of the ATP-binding cassette family. We chose the strategy to build our three-dimensional model of the ABCB1 transporter by homology. Atomic coordinates were then assayed for their reliability using the measured activity of some oxadiazolothiazin-3-one compounds. Once established their performance by docking analysis, we synthesized new compounds whose forecasted activity was tested by MTT and cytofluorimetric assays. Our docking model of MDR1, MONBD1, seems to reliably satisfy our need to design and forecast, on the basis of their LTCC blockers ability, the inhibitory activity of new molecules on the ABCB1 transporter.
No preview · Article · May 2013 · ACS Medicinal Chemistry Letters
[Show abstract][Hide abstract] ABSTRACT: In previous papers we demonstrated that the activity of short heteroretinoids as anti-proliferative and pro-apoptotic compounds was deeply linked to their heterocyclic moiety and that ionone-derived 1,5-pyrazoles had the highest anti-proliferative activity in our preliminary experiments. We then demonstrated the high and pharmacologically significant anti-proliferative and apoptotic activities of the pyrazole compounds 2-(1-(4-chlorophenyl)-1H-pyrazol-5-yl)-5-methoxyphenol (EN12-4), 5-methoxy-2-(1-(pyridin-2-yl)-1H-pyrazol-5-yl)phenol (EN12-2A) and 2-(5-(4-methoxyphenyl)-1H-pyrazol-1-yl)pyridine (EN7-2) establishing, especially for EN12-2A, a possible mechanism of action involving the cell microtubular system.
No preview · Article · May 2013 · Pharmacological reports: PR
[Show abstract][Hide abstract] ABSTRACT: 8-Hydroxyquinoline derivatives are metal-binding compounds that have recently attracted interest as therapeutic agents for cancer therapy. In this scenario, we designed and synthesized three new glucoconjugates, 5,7-dichloro-8-quinolinyl-β-d-glucopyranoside, 5-chloro-8-quinolinyl-β-d-glucopyranoside and 2-methyl-8-quinolinyl-β-d-glucopyranoside and investigated their biological properties in comparison to the parent 8-hydroxyquinoline derivatives in the presence of Cu(2+). In vitro data show that 2 out of 3 glycosylated compounds possess a pharmacologically-relevant antiproliferative activity against tumor cells, similar to that of their parent compounds; this activity is associated with a relevant triggering of apoptosis. The pharmacological profile of the glucoconjugates depends on the cellular enzymatic β-glucosidase activity, as demonstrated by the inhibition of antiproliferative activity in the presence of the 2,5-dideoxy-2,5-imino-d-mannitol.
Preview · Article · Nov 2012 · Dalton Transactions
[Show abstract][Hide abstract] ABSTRACT: Recently, it has been reported that compounds bearing a sulfonamide moiety possess many types of biological activities, including anticancer activity. The present work reports the synthesis and antiproliferative evaluation of some N-(6(4)-indazolyl)benzenesulfonamides and 7-ethoxy-N-(6(4)-indazolyl)benzenesulfonamides. All compounds were evaluated for their in vitro antiproliferative activity against three tumor cell lines: A2780 (human ovarian carcinoma) A549 (human lung adenocarcinoma) and P388 (murine leukemia). The results indicated that sulfonamides 2c, 3c, 6d, 8, 13, 3b and 16 were endowed with a pharmacologically interesting antiproliferative activity with compounds 2c and 3c showing the lower IC(50) (from 0.50 ± 0.09 to 1.83 ± 0.52 μM and from 0.58 ± 0.17 to 5.83 ± 1.83 μM, respectively). Moreover, these indazoles were able to trigger apoptosis through the upregulation of the typical apoptosis markers p53 and bax. As regard to the hypothetic targets of these compounds, a preliminary docking analysis showed that all compounds seemed to interact with β-tubulin, in particular compound 3b that showed the lower Ki. The cytofluorimetric analysis of the cell cycle phases indicates that all compounds, when administered at their IC(75), caused a block in the G2/M phase of the cell cycle with the generation of subpopulations of cells with a number of chromosome >4n. When the IC(50)s were applied we observed a prevalent block in the G0/G1 phase except for compounds 16 and 8 where a partial G2/M block was present with a concomitant decrease of cells in the G0/G1 and S phases of the cell cycle. Altogether these results suggest a possible, but not exclusive, interaction with microtubules.
Full-text · Article · Sep 2012 · European Journal of Medicinal Chemistry
[Show abstract][Hide abstract] ABSTRACT: Nuclear and cytoplasmic localization of mda-9/syntenin in uveal melanoma cell lines. Confocal microscopy of 92.1 and OMM2.5 cells stained for anti- mda-9/syntenin (green). Nuclei are stained with propidium iodide (red). Z-Y and Z-X sections through a 3-dimensional stack of confocal images show nuclear localization of mda-9/syntenin.
[Show abstract][Hide abstract] ABSTRACT: Liver metastases develop earlier in NOD/SCIDIL2Rγ null mice (NOG) (upper panels), than in nude mice (lower panels). NOG and NU/NU mice were imaged with IVIS imaging system at different time points (15, 22 and 30 days) following spleen transplantation of 105 92.1 or Mel 270 transduced with a retroviral vector containing the luciferase gene. The signal intensity in the region of interest (ROI) is shown in each mouse.
[Show abstract][Hide abstract] ABSTRACT: Uveal melanoma is an aggressive cancer that metastasizes to the liver in about half of the patients, with a high lethality rate. Identification of patients at high risk of metastases may provide indication for a frequent follow-up for early detection of metastases and treatment. The analysis of the gene expression profiles of primary human uveal melanomas showed high expression of SDCBP gene (encoding for syndecan-binding protein-1 or mda-9/syntenin), which appeared higher in patients with recurrence, whereas expression of syndecans was lower and unrelated to progression. Moreover, we found that high expression of SDCBP gene was related to metastatic progression in two additional independent datasets of uveal melanoma patients. More importantly, immunohistochemistry showed that high expression of mda-9/syntenin protein in primary tumors was significantly related to metastatic recurrence in our cohort of patients. Mda-9/syntenin expression was confirmed by RT-PCR, immunofluorescence and immunohistochemistry in cultured uveal melanoma cells or primary tumors. Interestingly, mda-9/syntenin showed both cytoplasmic and nuclear localization in cell lines and in a fraction of patients, suggesting its possible involvement in nuclear functions. A pseudo-metastatic model of uveal melanoma to the liver was developed in NOD/SCID/IL2Rγ null mice and the study of mda-9/syntenin expression in primary and metastatic lesions revealed higher mda-9/syntenin in metastases. The inhibition of SDCBP expression by siRNA impaired the ability of uveal melanoma cells to migrate in a wound-healing assay. Moreover, silencing of SDCBP in mda-9/syntenin-high uveal melanoma cells inhibited the hepatocyte growth factor (HGF)-triggered invasion of matrigel membranes and inhibited the activation of FAK, AKT and Src. Conversely syntenin overexpression in mda-9/syntenin-low uveal melanoma cells mediated opposite effects. These results suggest that mda-9/syntenin is involved in uveal melanoma progression and that it warrants further investigation as a candidate molecular marker of metastases and a potential therapeutic target.
[Show abstract][Hide abstract] ABSTRACT: Nuclear and cytoplasmic localization of mda-9/syntenin in primary uveal melanomas. Immunohystochemistry of primary uveal melanoma specimens for mda-9/syntenin showed prevalent nuclear (panel A) or cytoplasmic localization (panel B) in different primary uveal melanomas.
[Show abstract][Hide abstract] ABSTRACT: We synthesized thirty-six novel pyrazole derivatives and studied their antiproliferative activity in human ovarian adenocarcinoma A2780 cells, human lung carcinoma A549 cells, and murine P388 leukemia cells. Four of these substances were selected because of their higher antiproliferative activity and further analyses showed that they were all able to induce apoptosis, although to a different extent. The expression of p53 and p21(waf1), which induce apoptosis and cell cycle arrest, was evaluated by western blot analysis in cells treated with compound 12d. The analysis of the cell cycle showed that all the selected compounds cause a partial G2/M block and the formation of polyploid cells. Furthermore, the four selected compounds were tested for their interaction with the microtubular cytoskeletal system by docking analysis, tubulin polymerization assay and immunofluorescence staining, demonstrating that the compound 12d, unlike the other active derivatives, was able to significantly bind dimers of α- and β-tubulin, probably causing a molecular distortion resulting in the disassembly of microtubules.
Full-text · Article · Aug 2011 · European Journal of Medicinal Chemistry
[Show abstract][Hide abstract] ABSTRACT: Glioblastoma (GBM) is a deadly tumor, which in spite of surgery and radio/chemotherapy frequently undergoes relapses related to the infiltration of the normal parenchyma and to resistance to cytotoxic and radiation therapy. Immunotherapy may represent a promising approach, which may complement existing therapies with the aim of eliminating residual tumor cells, through their selective targeting by immune effector cells or antibodies. This goal can be achieved through different approaches, based either on the induction of an immune response of the host, or by the injection of in vitro generated effector cells or monoclonal antibodies. Recent advances in the immunobiology of GBM and of its stem cell compartment will help in the development of more effective immunotherapy protocols. To this aim, the identification of antigens and receptors involved in GBM/immune cell interactions and of GBM immune escape mechanisms will provide new targets and tools. In this review we will discuss active immunotherapy approaches, including molecular-defined, GBM cell-based and dendritic-cell based vaccines. In addition, cytokines such as interferons and several interleukins can be used to enhance the immune response, both as recombinant molecules and by gene transfer technologies. Monoclonal antibodies or other ligands specific for GBM- or neovasculature-associated targets are now available in different genetically modified formats and can be used as such or for the targeted delivery of active compounds. Finally the in vitro activation and expansion of specific or innate immunity effector cells endowed with anti-GBM properties may provide an additional weapon for adoptive imunotherapy approaches.
Full-text · Article · Aug 2011 · Current pharmaceutical design
[Show abstract][Hide abstract] ABSTRACT: The occurrence of drug resistance in oncology accounts for treatment failure and relapse of diverse tumor types. Cancers contain cells at various stages of differentiation together with a limited number of 'cancer-initiating cells' able to self-renew and divide asymmetrically, driving tumorigenesis. Cancer-initiating cells display a range of self-defense systems that include almost all mechanisms of drug-resistance. Different molecular pathways and markers, identified in this malignant sub-population, are becoming targets for novel compounds and for monoclonal antibodies, which may be combined with conventional drugs. These interventions might eliminate drug-resistant cancer-initiating cells and lead to remission or cure of cancer patients.
Full-text · Article · Feb 2011 · Drug discovery today
[Show abstract][Hide abstract] ABSTRACT: Normal somatic stem cells (SC) are naturally resistant to chemotherapeutic agents due to their expression of various membrane transporter molecules (such as MDR-1), detoxifying enzymes and DNA repair proteins. In addition, they also have a slow rate of cell turnover and therefore escape from chemotherapeutic agents that target rapidly replicating cells. Cancer stem cells (CSC), being the mutated counterparts of normal SC, also have similar properties, which allow them to survive therapy. These surviving CSC then repopulate the tumor, causing relapse. The purpose of this review is to understand the most current research into the cellular and molecular biology of CSC. Topics that will be explored are the origin of CSC, the CSC niche, the regulation of self-renewal in normal and cancer SC, and CSC as therapeutic targets.
Full-text · Article · Feb 2009 · Current Medicinal Chemistry
[Show abstract][Hide abstract] ABSTRACT: Glioblastoma, the most aggressive cerebral tumor, is invariably lethal. Glioblastoma cells express several genes typical of normal neural stem cells. One of them, SOX2, is a master gene involved in sustaining self-renewal of several stem cells, in particular neural stem cells. To investigate its role in the aberrant growth of glioblastoma, we silenced SOX2 in freshly derived glioblastoma tumor-initiating cells (TICs). Our results indicate that SOX2 silenced glioblastoma TICs, despite the many mutations they have accumulated, stop proliferating and lose tumorigenicity in immunodeficient mice. SOX2 is then also fundamental for maintenance of the self-renewal capacity of neural stem cells when they have acquired cancer properties. SOX2, or its immediate downstream effectors, would then be an ideal target for glioblastoma therapy.