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van Krieken J.H.,Radboud University Nijmegen | Siebers A.G.,Radboud University Nijmegen | Normanno N.,Cell Biology and Biotherapy Unit
Annals of Oncology | Year: 2013

Molecular testing of tumor samples to guide treatment decisions is of increasing importance. Several drugs have been approved for treatment of molecularly defined subgroups of patients, and the number of agents requiring companion diagnostics for their prescription is expected to rapidly increase. The results of such testing directly influence the management of individual patients, with both false-negative and false-positive results being harmful for patients. In this respect, external quality assurance (EQA) programs are essential to guarantee optimal quality of testing. There are several EQA schemes available in Europe, but they vary in scope, size and execution. During a conference held in early 2012, medical oncologists, pathologists, geneticists, molecular biologists, EQA providers and representatives from pharmaceutical industries developed a guideline to harmonize the standards applied by EQA schemes in molecular pathology. The guideline comprises recommendations on the organization of an EQA scheme, defining the criteria for reference laboratories, requirements for EQA test samples and the number of samples that are needed for an EQA scheme. Furthermore, a scoring system is proposed and consequences of poor performance are formulated. Lastly, the contents of an EQA report, communication of the EQA results, EQA databases and participant manual are given. © The Author 2013. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. Source

Roock W.D.,Catholic University of Leuven | Vriendt V.D.,Catholic University of Leuven | Normanno N.,Cell Biology and Biotherapy Unit | Ciardiello F.,The Second University of Naples | Tejpar S.,Catholic University of Leuven
The Lancet Oncology | Year: 2011

The discovery of mutant KRAS as a predictor of resistance to epidermal growth-factor receptor (EGFR) monoclonal antibodies brought a major change in the treatment of metastatic colorectal cancer. This seminal finding also highlighted our sparse knowledge about key signalling pathways in colorectal tumours. Drugs that inhibit oncogenic alterations such as phospho-MAP2K (also called MEK), phospho-AKT, and mutant B-RAF seem promising as single treatment or when given with EGFR inhibitors. However, our understanding of the precise role these potential drug targets have in colorectal tumours, and the oncogenic dependence that tumours might have on these components, has not progressed at the same rate. As a result, patient selection and prediction of treatment effects remain problematic. We review the role of mutations in genes other than KRAS on the efficacy of anti-EGFR therapy, and discuss strategies to target these oncogenic alterations alone or in combination with receptor tyrosine-kinase inhibition. © 2011 Elsevier Ltd. Source

Strizzi L.,Northwestern University | Margaryan N.V.,Northwestern University | Gilgur A.,Northwestern University | Hardy K.M.,Northwestern University | And 3 more authors.
Cell Cycle | Year: 2013

Cripto-1 (CR-1) protein function differs according to cellular or extracellular expression. In this study, we explore the significance of cell surface CR-1 expression in human melanoma cells. Cell surface CR-1-expressing human melanoma cells (CR1-CS+) were selected by fluorescence-activated cell sorting (FACS) and grown in vitro and in vivo in nude mice to study their growth characteristics. The CR1-CS+ melanoma cells were found to express increased levels of Oct4, MDR-1 and activated c-Src compared with cells lacking this subpopulation (CR1-CS-) or unsorted cells, used as control. CR1-CS+ show reduced proliferation rates and diminished spherical colony formation compared with control cells when cultured in vitro. Orthotopic injections of CR1-CS+ in nude mice formed slow growing tumors with histologic variability across different areas of the CR1-CS+ xenografts. CR-1-expressing cells from first generation CR1-CS+ tumors showed significantly increased tumor-forming rate and aggressiveness following subsequent transplants in nude mice. These data demonstrate that within a heterogeneous melanoma cell population there resides a slow proliferating, cell surface CR-1-expressing subpopulation capable of giving rise to a fast growing, aggressive progeny that may contribute to disease recurrence and progression. © 2013 Landes Bioscience. Source

Ciardiello F.,The Second University of Naples | Normanno N.,Cell Biology and Biotherapy Unit
Cancer Discovery | Year: 2011

Primary and acquired resistance to anti-epidermal growth factor receptor (EGFR) drugs are clinically relevant problems in patients with metastatic colorectal carcinoma. A complex network of molecular alterations is involved in this phenomenon. Bertotti et al. report the development of serially transplantable groups of tumor xenografts in immune-deficient mice from patient-derived, genetically characterized metastatic colorectal carcinoma samples. These experimental models ("xenopatients") might represent a novel approach to discover and characterize the mechanisms of resistance to anti-EGFR therapy and other molecularly targeted therapies in metastatic colorectal carcinoma. In this respect, Bertotti et al. were able to identify HER2 gene amplification as one such mechanism of resistance to anti-EGFR therapy. © 2011 American Association for Cancer Research. Source

De Luca A.,Cell Biology and Biotherapy Unit | Normanno N.,Cell Biology and Biotherapy Unit
IDrugs | Year: 2010

Tivozanib (AV-951; KRN-951), being developed by AVEO Pharmaceuticals Inc and Kyowa Hakko Kirin Co Ltd, is an orally active, ATP-competitive, small-molecule, quinoline-urea derivative that inhibits VEGFR tyrosine kinase for the potential treatment of cancer. In particular, tivozanib is able to markedly inhibit the ligand-induced phosphorylation of VEGFR-1, VEGFR-2 and VEGFR-3 at picomolar concentrations. In preclinical studies, tivozanib produced a significant inhibition of tumor growth and angiogenesis in several different xenograft tumor models in athymic rats. In a phase I clinical trial, tivozanib was safe and tolerable when administered at oral doses up to 1.5 mg on a schedule of 4 weeks on, 2 weeks off treatment. Results from a phase II clinical trial in patients with advanced renal cell carcinoma reported an overall response rate of 25.4% and a median progression-free survival of 11.8 months in patients treated with tivozanib as a single agent. Hypertension and dysphonia were the most frequent adverse events. At the time of publication, a phase III clinical trial was recruiting patients with advanced renal cancer to assess tivozanib in comparison with sorafenib. Clinical trials are currently ongoing to evaluate the safety and antitumor activity of tivozanib in breast, lung and colorectal cancer. Tivozanib might represent a promising anticancer agent in several different tumor types. © Thomson Reuters (Scientific) Ltd. Source

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