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Francesca Monteleone,
Roberta Rosa,
Monica Vitale,
Chiara D'Ambrosio,
Mariangela Succoio,
Luigi Formisano,
Lucia Nappi,
Maria Fiammetta Romano,
Andrea Scaloni,
Giampaolo Tortora, Roberto Bianco,
Nicola Zambrano
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ABSTRACT: Cetuximab is a chimeric antibody approved for the treatment of metastatic colorectal cancer that selectively targets epidermal growth factor receptor (EGFR) signalling. Treatment efficacy with this drug is often impaired by acquired resistance and poor information has been accumulated on the mechanisms underlying such a phenomenon. By taking advantage of a syngenic cellular system of sensitivity and acquired resistance to anti-EGFR therapy in the colorectal carcinoma GEO cell line, we profiled protein expression differences between Cetuximab-sensitive and resistant cells. Combined 2D-DIGE and MS analyses revealed a main proteomic signature resulting from selective deregulation of various metabolic enzymes, including glucose-6-phosphate dehydrogenase, transketolase, lactate dehydrogenase B and pyruvate dehydrogenase E1, which was also confirmed by western blotting experiments. Lactate dehydrogenase B down-regulation has been already related to an increased anaerobic utilization of glucose by tumor cells; accordingly, we verified that Cetuximab-resistant cells have a significantly higher production of lactate. Resistant cells also showed decreased NADPH levels. Observed protein deregulations were not related to functional alterations of the hypoxia-inducible factor 1-associated pathways. Our data demonstrate that increased anaerobic metabolism is a prominent feature observed in the GEO syngenic model of acquired resistance to anti-EGFR therapy in colorectal cancer.
Proteomics 12/2012; · 4.43 Impact Factor
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Roberta Rosa,
Roberta Marciano,
Umberto Malapelle,
Luigi Formisano,
Lucia Nappi,
Claudia D'Amato,
Valentina D'Amato,
Vincenzo Damiano,
Gabriella Marfe,
Silvana Del Vecchio,
Antonella Zannetti,
Adelaide Greco,
Alfonso De Stefano,
Chiara Carlomagno,
Bianca Maria Veneziani,
Giancarlo Troncone,
Sabino De Placido, Roberto Bianco
[show abstract]
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ABSTRACT: Purpose. Although the anti-Epidermal Growth Factor (EGFR) monoclonal antibody (mAb) cetuximab is an effective strategy in colorectal cancer therapy, its clinical use is limited by intrinsic or acquired resistance. Alterations in the 'sphingolipid rheostat' - the balance between the proapoptotic molecule ceramide and the mitogenic factor sphingosine-1-phosphate (S1P) - due to sphingosine kinase 1 (SphK1) overactivation have been involved in resistance to anticancer targeted agents. Moreover, cross-talks between SphK1 and EGFR-dependent signalling pathways have been described. Experimental design. We investigated SphK1 contribution to cetuximab resistance in colorectal cancer, in preclinical in vitro/in vivo models and in tumor specimens from patients. Results. SphK1 was found overexpressed and overactivated in colorectal cancer cells with intrinsic or acquired resistance to cetuximab. SphK1 contribution to resistance was supported by the demonstration that SphK1 inhibition by N,N-dimethyl-sphingosine (DMS) or silencing via siRNA in resistant cells restores sensitivity to cetuximab, whereas exogenous SphK1 overexpression in sensitive cells confers resistance to these agents. Moreover, treatment of resistant cells with fingolimod (FTY720), a S1P receptor (S1PR) antagonist, resulted in re-sensitization to cetuximab both in vitro and in vivo, with significant inhibition of tumor growth, interference with signal transduction, induction of cancer cells apoptosis and prolongation of mice survival. Finally, immunohistochemical analysis on colorectal cancer tissues revealed a correlation between SphK1 expression and cetuximab response. Conclusion. Our data could contribute to clarify SphK1 role in cetuximab resistance and may suggest SphK1 inhibition as a part of novel targeting strategies potentially effective also in resistant colorectal cancer patients.
Clinical Cancer Research 11/2012; · 7.74 Impact Factor
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ABSTRACT: The epidermal growth factor receptor (EGFR) autocrine pathway plays a crucial role in human cancer, contributing to a number
of highly relevant processes in tumor development and progression, including cell proliferation, regulation of apoptotic cell
death, angiogenesis, and metastatic spread. For these reasons, the EGFR is one of the most studied and exploited targets for
molecular cancer therapy. Two classes of anti-EGFR agents have entered clinical practice: monoclonal antibodies and small
molecules targeting the receptor tyrosine kinase. They have shown activity alone and in combination with conventional antitumor
treatments, such as chemotherapy or radiation therapy. However, preclinical and clinical studies have demonstrated the occurrence
of spontaneous or acquired resistance to these drugs. Since EGFR is implicated in a wide array of intracellular functions,
the phenomenon of resistance to its inhibitors may result from the derangement of different molecular pathways, including
autocrine/paracrine production of ligands, receptor mutations, constitutive activation of downstream signaling proteins, and
activation of alternative pathways. This review presents the experimental evidence underlying the main mechanisms of resistance
to EGFR inhibitors.
Targeted Oncology 04/2012; 2(1):31-37. · 0.46 Impact Factor
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Roberta Rosa,
Davide Melisi,
Vincenzo Damiano, Roberto Bianco,
Sonia Garofalo,
Teresa Gelardi,
Sudhir Agrawal,
Federica Di Nicolantonio,
Aldo Scarpa,
Alberto Bardelli,
Giampaolo Tortora
[show abstract]
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ABSTRACT: K-Ras somatic mutations are a strong predictive biomarker for resistance to epidermal growth factor receptor (EGFR) inhibitors in patients with colorectal and pancreatic cancer. We previously showed that the novel Toll-like receptor 9 (TLR9) agonist immunomodulatory oligonucleotide (IMO) has a strong in vivo activity in colorectal cancer models by interfering with EGFR-related signaling and synergizing with the anti-EGFR monoclonal antibody cetuximab.
In the present study, we investigated, both in vitro and in vivo, the antitumor effect of IMO alone or in combination with cetuximab in subcutaneous colon and orthotopic pancreatic cancer models harboring K-Ras mutations and resistance to EGFR inhibitors.
We showed that IMO was able to significantly restore the sensitivity of K-Ras mutant cancer cells to cetuximab, producing a marked inhibition of cell survival and a complete suppression of mitogen-activated protein kinase phosphorylation, when used in combination with cetuximab. IMO interfered with EGFR-dependent signaling, modulating the functional interaction between TLR9 and EGFR. In vivo, IMO plus cetuximab combination caused a potent and long-lasting cooperative antitumor activity in LS174T colorectal cancer and in orthotopic AsPC1 pancreatic cancer. The capability of IMO to restore cetuximab sensitivity was further confirmed by using K-Ras mutant colorectal cancer cell models obtained through homologous recombination technology.
We showed that IMO markedly inhibits growth of K-Ras mutant colon and pancreatic cancers in vitro and in nude mice and cooperates with cetuximab via multiple mechanisms of action. Therefore, we propose IMO plus cetuximab as a therapeutic strategy for K-Ras wild-type as well for K-Ras mutant, cetuximab-resistant colorectal and pancreatic cancers.
Clinical Cancer Research 09/2011; 17(20):6531-41. · 7.74 Impact Factor
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ABSTRACT: Patients with metastatic colorectal cancer (mCRC) receiving all three active drugs (irinotecan, oxaliplatin, fluorouracil) achieve the best outcome. Bevacizumab added to chemotherapy further improves progression-free (PFS) survival and overall survival. As arterial hypertension has been reported in all studies involving bevacizumab, we retrospectively analysed the correlation between the modifications of arterial blood pressure and response rate (RR) and PFS in mCRC patients treated with bevacizumab.
Patients with histologically proven mCRC receiving a first-line chemotherapeutic treatment were eligible. Arterial blood pressure was measured daily and hypertension graduated according to NCI-CTC V3.0 scale.
Seventy-four patients were considered for the present analysis; median age was 57 years (range 31-80). Sixty-seven patients had undergone surgery on primary tumour and, of these, 19 patients had formerly received adjuvant chemotherapy for stage II-III tumours. Chemotherapeutic regimens for metastatic disease were FOLFIRI (61 patients), FOLFOXIRI (6 patients), XELOX (5 patients) and XELIRI (2 patients). Eighteen patients (24.3%) had basal hypertension. Thirteen patients (17.6%) developed G2-G4 arterial hypertension. Six complete (8.1%) and 31 partial (41.9%) responses were recorded. Among patients with induced arterial hypertension, 84.6% achieved a complete or partial response, as compared with 42.6% of patients who did not show this side effect (P = 0.006). Kaplan-Meier analysis showed a statistically significant improvement in median PFS for patients with induced arterial hypertension (15.1 vs. 8.3 months, P = 0.04).
Our data suggest that bevacizumab-related arterial hypertension may represent a predictive factor of response and prolonged PFS in patients with mCRC receiving first-line bevacizumab.
Cancer Chemotherapy and Pharmacology 03/2011; 68(5):1207-13. · 2.83 Impact Factor
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ABSTRACT: The combination of EGFR inhibitors and anti-angiogenic drugs has a strong pre-clinical rationale, yet its use has produced controversial clinical results. We conducted two sequential phase I trials to evaluate the feasibility and the recommended dose of erlotinib when combined with fluoropyrimidine-oxaliplatin-based chemotherapy with or without bevacizumab. A total of 21 metastatic colorectal cancer (mCRC) patients were treated in two sequential phase I trials. In the first trial, 12 patients were treated with escalating doses of erlotinib plus FOLFOX. In the second, 9 patients were treated with escalating doses of erlotinib combined with oxaliplatin, capecitabine and bevacizumab. No MTD was reached in either of the trials. The only dose-limiting toxicities observed were neutropenia and diarrhea. No unexpected toxicities were noted. Hematological toxicity was the most frequently noted adverse event with infusional 5FU therapy, while gastrointestinal toxicity was the most common adverse event. In the second trial most patients withdrew from treatment due to toxicity, and less than half completed the therapeutic program as per protocol, mostly due to toxicity. In conclusion, the present study confirms the disappointing results of the double combination of EGFR inhibitors and anti-angiogenic drugs in mCRC patients.
Experimental and therapeutic medicine 01/2011; 2(3):449-455.
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A Teresa Alberobello,
Vittoria D'Esposito,
Daniela Marasco,
Nunzianna Doti,
Menotti Ruvo, Roberto Bianco,
Giampaolo Tortora,
Iolanda Esposito,
Francesca Fiory,
Claudia Miele,
Francesco Beguinot,
Pietro Formisano
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ABSTRACT: Insulin-like growth factor-1 (IGF-1) signaling system exerts a broad antiapoptotic function and plays a crucial role in resistance to anticancer therapies. Exposure of MCF-7 breast cancer cells to IGF-1 rapidly and transiently induced tyrosine phosphorylation and activation of phosphoinositide-dependent kinase-1 (PDK1). This was paralleled by Akt/protein kinase B and protein kinase C-zeta phosphorylation, at Thr(308) and Thr(410), respectively. IGF-1 treatment also enhanced PDK1 interaction with IGF-1 receptor (IGF-1R) in intact MCF-7 cells. Pulldown assays revealed that PDK1 bound IGF-1R in vitro and that the region encompassing amino acids 51-359 of PDK1 was necessary for the interaction. Synthetic peptides corresponding to IGF-1R C terminus amino acids 1295-1337 (C43) and to PDK1 amino acids 114-141 reduced in vitro IGF-1R/PDK1 interaction in a concentration-dependent manner. Loading of fluoresceinated-C43 (fluorescein isothiocyanate (FITC)-C43) into MCF-7 cells significantly reduced IGF-1R/PDK1 interaction and phosphorylation of PDK1 substrates. Moreover, FITC-C43 intracellular loading reverted the protective effect of IGF-1 on growth factor deprivation-induced cell death. Finally, the inhibition of IGF-1R/PDK1 interaction and signaling by FITC-C43 was accompanied by 2-fold enhanced killing capacity of cetuximab in human GEO colon adenocarcinoma cells and was sufficient to restore cell death in cetuximab-resistant cell clones. Thus, disruption of PDK1 interaction with IGF-1R reduces IGF-1 survival effects in cancer cells and may enhance cell death by anticancer agents.
Journal of Biological Chemistry 02/2010; 285(9):6563-72. · 4.77 Impact Factor
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Chiara Carlomagno,
Elide Matano, Roberto Bianco,
Carolina Cimminiello,
Antonella Prudente,
Clorindo Pagliarulo,
Anna Crispo,
Lucia Cannella,
Alfonso DE Stefano,
Francesco Paolo D'Armiento,
Sabino DE Placido
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ABSTRACT: The aim of the present study was to evaluate the toxicity and efficacy of the FOLFOX-4 regimen as adjuvant chemotherapy in patients with gastric cancer after radical surgery. Fifty-four patients (1 stage Ib, 6 stage II, 22 stage IIIa, 14 stage IIIb and 11 stage IV) received 8-12 cycles of FOLFOX-4 (oxaliplatin 85 mg/m(2), Day 1; leucovorin 100 mg/m(2) i.v., Days 1 and 2; 5-fluorouracil 400 mg/m(2) i.v. bolus, Days 1 and 2 and 600 mg/m(2) in 22 h i.v. continuous infusion, Days 1 and 2; every 14 days). Toxicity was recorded at each cycle according to the National Cancer Institute Common Toxicity Criteria. Disease-free (DFS) and overall survival (OS) were calculated according to the Kaplan-Meier method. Thirty-eight patients (70.4%) completed the prescribed number of cycles of chemotherapy. The toxicity was mild. Grade 3-4 neutropenia occurred in 57% of patients, thrombocytopenia and anemia in 2% of cases. Peripheral neuropathy was experienced by 46% of the patients (grade 4 in 2% of cases). Five patients experienced grade 3 gastrointestinal toxicity. After a median follow-up of 33.1 months, 17 patients relapsed and 17 succumbed to the disease. The mean observed DFS and OS were 49.7 months (range 40.7-58.8) and 57.9 months (range 49.6-66.2), respectively. At univariate analysis, females and patients who had received <8 cycles of chemotherapy had a significantly worse probability of DFS and OS. The Cox model showed gender to be independent of the factors affecting DFS. Adjuvant FOLFOX-4 is feasible and well-tolerated in patients radically resected for gastric cancer. Receiving <4 months of adjuvant FOLFOX-4 could be detrimental to prognosis.
Experimental and therapeutic medicine 01/2010; 1(4):611-617.
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Vincenzo Damiano,
Sonia Garofalo,
Roberta Rosa, Roberto Bianco,
Rosa Caputo,
Teresa Gelardi,
Gerardina Merola,
Luigi Racioppi,
Corrado Garbi,
Ekambar R Kandimalla,
Sudhir Agrawal,
Giampaolo Tortora
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ABSTRACT: Resistance to anti-HER2 monoclonal antibody trastuzumab is a relevant issue in breast cancer patients. Among the mechanisms implicated in trastuzumab resistance, increasing evidence supports a role of tumor microenvironment. We previously found that a novel toll-like receptor 9 agonist, referred to as immune modulatory oligonucleotide (IMO) and currently under clinical investigation, acts through epidermal growth factor receptor (EGFR) and shows direct antiangiogenic effects by cooperating with anti-EGFR or anti-VEGF drugs, thus interfering with cancer cells and microenvironment.
In this study, we used KPL-4 and JIMT-1 trastuzumab-resistant breast cancer cells to evaluate the combination IMO plus trastuzumab as a therapeutic option for trastuzumab-resistant breast cancers.
IMO inhibits KPL-4 and JIMT-1 xenografts growth and potentiates trastuzumab antitumor effect, with complete suppression of tumor growth, potent enhancement of trastuzumab-mediated antibody-dependent cell-mediated cytotoxicity, and strong inhibition of EGFR/HER2-related signaling. In KPL-4 xenografts, IMO alone interferes with HER signal transduction, whereas trastuzumab is ineffective. IMO induces an HER-dependent signal inhibition also in vitro by modulating a functional interaction between toll-like receptor 9 and HER receptors occurring at membrane level. Finally, IMO plus trastuzumab produces a cooperative antiangiogenic effect related to suppression of endothelial HER-related signaling.
We showed a cooperative effect of IMO plus trastuzumab in trastuzumab-resistant breast cancers due to IMO direct antitumor and antiangiogenic activity and antibody-dependent cell-mediated cytotoxicity enhancement. Moreover, we provided first evidence of a toll-like receptor 9/HER interaction at membrane level as novel mechanism of action. Altogether, we propose IMO plus trastuzumab as an effective strategy in trastuzumab-resistant breast cancers.
Clinical Cancer Research 11/2009; 15(22):6921-30. · 7.74 Impact Factor
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Roberto Bianco,
Roberta Rosa,
Vincenzo Damiano,
Gennaro Daniele,
Teresa Gelardi,
Sonia Garofalo,
Valeria Tarallo,
Sandro De Falco,
Davide Melisi,
Roberto Benelli,
Adriana Albini,
Anderson Ryan,
Fortunato Ciardiello,
Giampaolo Tortora
[show abstract]
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ABSTRACT: The resistance to selective EGFR inhibitors involves the activation of alternative signaling pathways, and Akt activation and VEGF induction have been described in EGFR inhibitor-resistant tumors. Combined inhibition of EGFR and other signaling proteins has become a successful therapeutic approach, stimulating the search for further determinants of resistance as basis for novel therapeutic strategies.
We established human cancer cell lines with various degrees of EGFR expression and sensitivity to EGFR inhibitors and analyzed signal transducers under the control of EGFR-dependent and EGFR-independent pathways.
Multitargeted inhibitor vandetanib (ZD6474) inhibited the growth and the phosphorylation of Akt and its effector p70S6 kinase in both wild-type and EGFR inhibitor-resistant human colon, prostate, and breast cancer cells. We found that the resistant cell lines exhibit, as common feature, VEGFR-1/Flt-1 overexpression, increased secretion of VEGF and placental growth factor, and augmented migration capabilities and that vandetanib is able to antagonize them. Accordingly, a new kinase assay revealed that in addition to VEGF receptor (VEGFR)-2, RET, and EGFR, vandetanib efficiently inhibits also VEGFR-1. The contribution of VEGFR-1 to the resistant phenotype was further supported by the demonstration that VEGFR-1 silencing in resistant cells restored sensitivity to anti-EGFR drugs and impaired migration capabilities, whereas exogenous VEGFR-1 overexpression in wild-type cells conferred resistance to these agents.
This study shows that VEGFR-1 contributes to anti-EGFR drug resistance in different human cancer cells. Moreover, vandetanib inhibits VEGFR-1 activation, cell proliferation, and migration, suggesting its potential utility in patients resistant to EGFR inhibitors.
Clinical Cancer Research 09/2008; 14(16):5069-80. · 7.74 Impact Factor
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Antonella Zannetti,
Francesca Iommelli,
Rosa Fonti,
Angela Papaccioli,
Jvana Sommella,
Anna Lettieri,
Giuseppe Pirozzi, Roberto Bianco,
Giampaolo Tortora,
Marco Salvatore,
Silvana Del Vecchio
[show abstract]
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ABSTRACT: To test whether epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) induce detectable signals in tumor cells and whether such signals may reveal alterations of the apoptotic program.
Tumor cells were treated with gefitinib or erlotinib and tested for their ability to accumulate 99mTc-Sestamibi, a radiolabeled lipophilic cation that localizes in mitochondria. Then we tested whether Bcl-2 and Bcl-xL alter the pattern of drug-dependent tracer accumulation while reducing tumor cell sensitivity to EGFR TKIs. The mechanism underlying the pattern of tracer accumulation was elucidated. Finally, imaging studies were done in animal models and lung cancer patients before and after treatment with EGFR TKIs using single-photon emission computed tomography and 99mTc-Sestamibi.
Gefitinib increases accumulation of 99mTc-Sestamibi in Bcl-2-overexpressing cells and enhances the physical interaction of phosphorylated Bcl-2 with inositol trisphosphate receptor type 3 (IP3R3). Consequently, a relative increase of cytosolic and mitochondrial calcium levels occurs. Similarly, lung cancer cells showed an increase of tracer uptake and an enhanced interaction of Bcl-xL with IP3R3 on exposure to erlotinib concentrations achievable in plasma. The occurrence of these interactions was associated with an enhanced EGFR TKI-induced apoptosis resistance. Posttreatment imaging studies in nude mice bearing control and Bcl-2-overexpressing breast carcinomas showed a high tumor uptake of the tracer whereas baseline studies failed to visualize tumors. Similarly, an enhancement of tracer uptake could be detected in patients with lung cancer treated with erlotinib.
EGFR TKIs generate detectable signals by Bcl-2/Bcl-xL modulation of IP3R3 in tumor cells.
Clinical Cancer Research 09/2008; 14(16):5209-19. · 7.74 Impact Factor
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ABSTRACT: Background: The ‘targeted therapy’ has been defined as an innovative therapy designed to interfere with molecular targets playing a critical role in tumour growth or progression. The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor mediating the effect of growth factors both in physiological and pathological conditions; aberrations in the EGFR may result in the development of a tumour phenotype. Objective: To summarise the current state of the development of anti-EGFR drugs. Methods: Patent literature and preclinical/clinical studies about EGFR inhibitors are analysed. Conclusion: Some monoclonal antibodies and small-molecule tyrosine kinase inhibitors have been approved in several countries for the treatment of various human cancer types; moreover, more than ten EGFR-targeting agents are actually in advanced clinical development.
08/2008; 18(8):889-901.
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ABSTRACT: In recent years, the epidermal growth factor receptor (EGFR) has been recognized as a central player and regulator of cancer cell proliferation, apoptosis and angiogenesis and, therefore, as a potentially relevant therapeutic target. Several strategies for EGFR targeting have been developed, the most succesful being represented by monoclonal antibodies, that directly interfere with ligand-receptor binding and small molecule tyrosine kinase inhibitors, that interfere with activation/phosphorylation of EGFR. These agents have been authorized in advanced chemorefractory cancers, including colorectal cancer, non-small-cell lung cancer and head and neck cancer. However, evidence of resistance to these drugs has been described and extensive studies have been performed to investigate whether resistance to EGFR-targeted therapy is primary or secondary. Cellular levels of EGFR do not always correlate with response to the EGFR inhibitors. Indeed, in spite of the over expression and efficient inhibition of EGFR, resistance to EGFR inhibitors may occur. Moreover, given the genetic instability of cancer cells, genetic modifications could enable them to acquire a resistant phenotype to anti-EGFR therapies. Taken together, these findings support the importance of understanding the molecular mechanisms affecting cancer cell sensitivity or resistance to such inhibitors. This review will focus on the most relevant mechanisms contributing to the acquisition of sensitivity/resistance to EGFR inhibitors.
Differentiation 12/2007; 75(9):788-99. · 2.81 Impact Factor
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Vincenzo Damiano,
Rosa Caputo,
Sonia Garofalo, Roberto Bianco,
Roberta Rosa,
Gerardina Merola,
Teresa Gelardi,
Luigi Racioppi,
Gabriella Fontanini,
Sabino De Placido,
Ekambar R Kandimalla,
Sudhir Agrawal,
Fortunato Ciardiello,
Giampaolo Tortora
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ABSTRACT: Synthetic agonists of Toll-like receptor 9 (TLR9), a class of agents that induce specific immune response, exhibit antitumor activity and are currently being investigated in cancer patients. Intriguingly, their mechanisms of action on tumor growth and angiogenesis are still incompletely understood. We recently discovered that a synthetic agonist of TLR9, immune modulatory oligonucleotide (IMO), acts by impairing epidermal growth factor receptor (EGFR) signaling and potently synergizes with anti-EGFR antibody cetuximab in GEO human colon cancer xenografts, whereas it is ineffective in VEGF-overexpressing cetuximab-resistant GEO cetuximab-resistant (GEO-CR) tumors. VEGF is activated by EGFR, and its overexpression causes resistance to EGFR inhibitors. Therefore, we used IMO and the anti-VEGF antibody bevacizumab as tools to study IMO's role on EGFR and angiogenesis and to explore its therapeutic potential in GEO, LS174T, and GEO-CR cancer xenografts. We found that IMO enhances the antibody-dependent cell-mediated cytotoxicity (ADCC) activity of cetuximab, that bevacizumab has no ADCC, and IMO is unable to enhance it. Nevertheless, the IMO-plus-bevacizumab combination synergistically inhibits the growth of GEO and LS174T as well as of GEO-CR tumors, preceded by inhibition of signaling protein expression, microvessel formation, and human, but not murine, VEGF secretion. Moreover, IMO inhibited the growth, adhesion, migration, and capillary formation of VEGF-stimulated endothelial cells. The antitumor activity was irrespective of the TLR9 expression on tumor cells. These studies demonstrate that synthetic agonists of TLR9 interfere with growth and angiogenesis also by EGFR- and ADCC-independent mechanisms affecting endothelial cell functions and provide a strong rationale to combine IMO with bevacizumab and EGFR inhibitory drugs in colon cancer patients.
Proceedings of the National Academy of Sciences 08/2007; 104(30):12468-73. · 9.68 Impact Factor
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ABSTRACT: Accumulating evidence suggests that cancer can be envisioned as a "signaling disease", in which alterations in the cellular genome affect the expression and/or function of oncogenes and tumour suppressor genes. This ultimately disrupts the physiologic transmission of biochemical signals that normally regulate cell growth, differentiation and programmed cell death (apoptosis). From a clinical standpoint, signal transduction inhibition as a therapeutic strategy for human malignancies has recently achieved remarkable success. However, as additional drugs move forward into the clinical arena, intrinsic and acquired resistance to "targeted" agents becomes an issue for their clinical utility. One way to overcome resistance to targeted agents is to identify genetic and epigenetic aberrations underlying sensitivity/resistance, thus enabling the selection of patients that will most likely benefit from a specific therapy. Since resistance often ensues as a result of the concomitant activation of multiple, often overlapping, signaling pathways, another possibility is to interfere with multiple, cross-talking pathways involved in growth and survival control in a rational, mechanism-based, fashion. These concepts may be usefully applied, among others, to agents that target two major signal transduction pathways: the one initiated by epidermal growth factor receptor (EGFR) signaling and the one converging on mitogen-activated protein kinase (MAPK) activation. Here, we review the molecular mechanisms of sensitivity/resistance to EGFR inhibitors, as well as the rationale for combining them with other targeted agents, in an attempt to overcome resistance. In the second part of the paper, we review MAPK-targeted agents, focusing on their therapeutic potential in haematologic malignancies, and examine the prospects for combinations of MAPK inhibitors with cytotoxic agents or other signal transduction-targeted agents to obtain synergistic anti-tumour effects.
Drug Resistance Updates 07/2007; 10(3):81-100. · 9.56 Impact Factor
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ABSTRACT: The epidermal growth factor receptor (EGFR) has been widely used as a target for novel anticancer agents, such as blocking antibodies and small molecular weight tyrosine kinase compounds. In spite of recent advances in cancer cell biology, leading to the introduction of clinically active new drugs, such as cetuximab, panitumumab and erlotinib, unfortunately disease control remains unsuccessful due to the presence of constitutive resistance to EGFR inhibitors in most patients and the development of acquired resistance in the responders. A large number of molecular abnormalities in tumor cells seem to partly contribute to their resistance to anti-EGFR therapy: increased angiogenesis, constitutive activation of downstream mediators, overexpression of other tyrosine kinase receptors. Moreover, some mutations in the EGFR receptor kinase domain seem to play a crucial role in determining the sensitivity of cancer cells to specific inhibitors by altering the conformation of the receptor and its activity. The development of rational combinations of anticancer agents and EGFR inhibitors, able to exert synergistic cytotoxic interactions, has been widely accepted and used in both preclinical and clinical studies. Although the failure of large clinical trial based on empirical combination of anti-EGFR and classic chemotherapeutic agents, several preclinical data seems to support the hypothesis that combining EGFR inhibitors and other novel agents could efficiently inhibit tumor growth and overcome intrinsic resistance to a single-agent based therapy. This review focuses on the role of complementary signalling pathways in the development of resistance to EGFR targeting agents and the rationale to combine novel inhibitors as anticancer therapy.
Current pharmaceutical design 02/2007; 13(33):3358-67. · 4.41 Impact Factor
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ABSTRACT: Growth factor receptors and their ligands not only regulate normal cell processes but have been also identified as key regulators of human cancer formation. The epidermal growth factor receptor (EGFR/ErbB1/HER1) belongs to the ErbB/HER-family of tyrosine kinase receptors (RTKs). These trans-membrane proteins are activated following binding with peptide growth factors of the EGF-family of proteins. Several evidences suggest that cooperation of multiple ErbB receptors and ligands is required for the induction of cell transformation. In this respect, EGFR, upon activation, sustains a complex and redundant network of signal transduction pathways with the contribution of other trans-membrane receptors. EGFR has been found to be expressed and altered in a variety of malignancies and clearly it plays a significant role in tumor development and progression, including cell proliferation, regulation of apoptotic cell death, angiogenesis and metastatic spread. Moreover, amplification of the EGFR gene and mutations in the EGFR tyrosine kinase domain have been recently reported in human carcinomas. As a result, investigators have developed approaches to inhibit the effects of EGFR activation, with the aim of blocking tumor growth and invasion. A number of agents targeting EGFR, including specific antibodies directed against its ligand-binding domain and small molecules inhibiting its tyrosine kinase activity are either in clinical trials or are already approved for clinical treatment. This article reviews the EGFR role in carcinogenesis and tumor progression as rational bases for the development of specific therapeutic inhibitors.
The International Journal of Biochemistry & Cell Biology 02/2007; 39(7-8):1416-31. · 4.63 Impact Factor
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Maria Pia Morelli,
Tina Cascone,
Teresa Troiani,
Concetta Tuccillo, Roberto Bianco,
Nicola Normanno,
Marco Romano,
Bianca Maria Veneziani,
Gabriella Fontanini,
S Gail Eckhardt,
Sabino De Pacido,
Giampaolo Tortora,
Fortunato Ciardiello
[show abstract]
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ABSTRACT: The epidermal growth factor receptor (EGFR) autocrine pathway plays an important role in cancer cell growth. Vascular endothelial growth factor A (VEGF-A) is a key regulator of tumor-induced endothelial cell proliferation and vascular permeability. ZD6474 is an orally available, small molecule inhibitor of VEGF receptor-2 (VEGFR-2), EGFR and RET tyrosine kinase activity. We investigated the activity of ZD6474 in combination with cetuximab, an anti-EGFR blocking monoclonal antibody, to determine the anti-tumor activity of EGFR blockade through the combined use of two agents targeting the receptor at different molecular sites in cancer cells and of VEGFR-2 blockade in endothelial cells.
The anti-tumor activity in vitro and in vivo of ZD6474 and/or cetuximab was tested in human cancer cell lines with a functional EGFR autocrine pathway.
The combination of ZD6474 and cetuximab determined synergistic growth inhibition in all cancer cell lines tested as assessed by the Chou and Talalay method. In nude mice bearing established human colon carcinoma (GEO) or lung adenocarcinoma (A549) xenografts and treated with ZD6474 and/or cetuximab for 4 weeks, a reversible tumor growth inhibition was caused by each drug. In contrast, a more significant tumor growth delay resulted from the combination of the two agents with an approximately 100-110 days increase in mice median overall survival as compared to single agent treatment.
This study provides a rationale for evaluating in a clinical setting the double blockade of EGFR in combination with inhibition of VEGFR-2 signaling as cancer therapy.
Journal of Cellular Physiology 09/2006; 208(2):344-53. · 3.87 Impact Factor
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ABSTRACT: Growth factor signals are propagated from the cell surface, through the action of transmembrane receptors, to intracellular effectors that control critical functions in human cancer cells, such as differentiation, growth, angiogenesis, and inhibition of cell death and apoptosis. Several kinases are involved in transduction pathways via sequential signalling activation. These kinases include transmembrane receptor kinases (e.g., epidermal growth factor receptor EGFR); or cytoplasmic kinases (e.g., PI3 kinase). In cancer cells, these signalling pathways are often altered and results in a phenotype characterized by uncontrolled growth and increased capability to invade surrounding tissue. Therefore, these crucial transduction molecules represent attractive targets for cancer therapy. This review will summarize current knowledge of key signal transduction pathways, that are altered in cancer cells, as therapeutic targets for novel selective inhibitors. The most advanced targeted agents currently under development interfere with function and expression of several signalling molecules, including the EGFR family; the vascular endothelial growth factor and its receptors; and cytoplasmic kinases such as Ras, PI3K and mTOR.
European Journal of Cancer 03/2006; 42(3):290-4. · 5.54 Impact Factor
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Chiara Carlomagno,
Michele Orditura,
Stefano Pepe,
Ferdinando De Vita,
Carmela Romano,
Fortunato Ciardiello,
Claudia Ferrara,
Erika Martinelli, Roberto Bianco,
Gaetano Aurilio,
Diego D'Agostino,
Giampaolo Tortora,
Giuseppe Catalano,
Sabino De Placido
[show abstract]
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ABSTRACT: To investigate the maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) of capecitabine plus oxaliplatin.
Oxaliplatin was given by 2-hour iv infusion on days 1 and 8, and capecitabine was given orally, from day 1 to 14, every 3 weeks. We tested 4 levels of doses: 1) capecitabine 1650 mg/m2 + oxaliplatin 50 mg/m2; 2) capecitabine 2000 mg/m2 + oxaliplatin 50 mg/m2; 3) capecitabine 2000 mg/m2 + oxaliplatin 60 mg/m2; and 4) capecitabine 2500 mg/m2 + oxaliplatin 60 mg/m2. Patients with gastrointestinal neoplasm were eligible for the study.
Thirty-two patients were enrolled. At dose level 4, 3 patients had unacceptable toxicity (grade 3 diarrhea, grade 4 diarrhea, and grade 3 mucositis, respectively), thus, level 4 was the MTD. Apart from DLT, overall toxicity was mild: grade > or =3 nonhematological toxicity occurred in 3 patients, and hematological toxicity was sporadic.
This study demonstrates that clinically relevant doses of capecitabine (2000 mg/m2 from day 1 to 14) plus oxaliplatin (60 mg/m2 on days 1 and 8) every 3 weeks can be given without causing unacceptable toxicity.
American journal of clinical oncology 02/2006; 29(1):85-9. · 2.21 Impact Factor
