2451
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Winder T, Lenz HJ. Vascular endothelial growth factor and epidermal growth factor signaling pathways as therapeutic targets for colorectal cancer. Gastroenterology 2010; 138:2163-76. [PMID: 20420953 DOI: 10.1053/j.gastro.2010.02.005] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 02/04/2010] [Accepted: 02/07/2010] [Indexed: 01/12/2023]
Abstract
Treatment of colorectal cancer (CRC) has developed considerably over the past decade, especially in the areas of targeted therapeutics and biomarker development. Multiple cellular pathways influence the growth and metastatic potential of CRC. Targeted therapies have been designed to interfere with specific molecular events in pathways that mediate tumor growth and progression. Preclinical and clinical studies have shown that the epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) are valid therapeutic targets for patients with CRC. Monoclonal antibodies and tyrosine kinase inhibitors have been developed to target EGFR, VEGF, and VEGF receptors (VEGFRs) and are important additions to CRC treatment options. We review the most recent data on the VEGF and EGFR signaling pathways and therapeutic reagents designed to target them, provide insights into their mechanisms, and describe results from recent clinical trials.
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Affiliation(s)
- Thomas Winder
- Division of Medical Oncology, University of Southern California/Norris Comprehensive Cancer Center, Keck School of Medicine, Los Angeles, California, USA
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2452
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Ouwerkerk J, Boers-Doets C. Best practices in the management of toxicities related to anti-EGFR agents for metastatic colorectal cancer. Eur J Oncol Nurs 2010; 14:337-49. [PMID: 20580896 DOI: 10.1016/j.ejon.2010.03.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 03/17/2010] [Accepted: 03/24/2010] [Indexed: 10/19/2022]
Abstract
PURPOSE To provide oncology nurses with an overview of the toxicity management associated with the anti-epidermal growth factor receptor (EGFR) monoclonal antibodies cetuximab and panitumumab in patients with metastatic colorectal cancer. METHODS Monoclonal antibodies such as cetuximab and panitumumab that target EGFR have provided patients with metastatic colorectal cancer with effective treatment options. Both antibodies can be used as monotherapy; cetuximab is also approved for use in combination with chemotherapy. We reviewed the literature regarding the signs and symptoms, assessment of severity, and strategies available to prevent and manage adverse events associated with these agents. KEY RESULTS This class of therapeutics is associated with an overall acceptable adverse event profile that is distinctly different from conventional chemotherapeutics. In contrast to cytotoxic chemotherapy, which causes myelosuppression, mucositis, and nausea and vomiting, common toxicities reported for anti-EGFR therapy include the more frequent cutaneous toxicities, electrolyte imbalances, and diarrhoea, as well as the less frequent ocular toxicities. Infusion reactions are also observed with the chimerical monoclonal antibody cetuximab. CONCLUSIONS Oncology nurses play a key role in the administration of multi-agent treatment regimens, especially with respect to the identification and management of toxicities, patient education, and patient support. By reducing the incidence and severity of the adverse events associated with anti-EGFR therapy, oncology nurses have the potential to sustain patient adherence to completion of treatment, identify signs and symptoms early, proactively manage adverse events, and provide appropriate treatment interventions, thereby improving patient quality of life.
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Affiliation(s)
- Jan Ouwerkerk
- Department of Clinical Oncology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
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2453
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Peppercorn J, Shapira I, Collyar D, Deshields T, Lin N, Krop I, Grunwald H, Friedman P, Partridge AH, Schilsky RL, Bertagnolli MM. Ethics of mandatory research biopsy for correlative end points within clinical trials in oncology. J Clin Oncol 2010; 28:2635-40. [PMID: 20406927 PMCID: PMC5596502 DOI: 10.1200/jco.2009.27.2443] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Accepted: 02/23/2010] [Indexed: 01/21/2023] Open
Abstract
Clinical investigators in oncology are increasingly interested in using molecular analysis of cancer tissue to understand the biologic bases of response or resistance to novel interventions and to develop prognostic and predictive biomarkers that will guide clinical decision making. Some scientific questions of this nature can only be addressed, or may best be addressed, through the conduct of a clinical trial in which research biopsies are obtained from all participants. However, trial designs with mandatory research biopsies have raised ethical concerns related to the risk of harm to participants, the adequacy of voluntary informed consent, and the potential for misunderstanding among research participants when access to an experimental intervention is linked to the requirement to undergo a research biopsy. In consideration of the ethical and scientific issues at stake in this debate, the Cancer and Leukemia Group B Ethics Committee proposes guidelines for clinical trials involving mandatory research biopsies. Any cancer clinical trial that requires research biopsies of participants must be well designed to address the scientific question, obtain the biopsy in a way that minimizes risk, and ensure that research participants are fully informed of the risks, rationale, and requirements of the study, as well as of treatment alternatives. Further guidelines and discussions of this issue are specified in this position paper. We feel that if these principles are respected, an informed adult with cancer can both understand and voluntarily consent to participation in a clinical trial involving mandatory research biopsy for scientific end points.
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Affiliation(s)
- Jeffrey Peppercorn
- Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, USA.
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2454
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Amann JM, Lee JW, Roder H, Brahmer J, Gonzalez A, Schiller JH, Carbone DP. Genetic and proteomic features associated with survival after treatment with erlotinib in first-line therapy of non-small cell lung cancer in Eastern Cooperative Oncology Group 3503. J Thorac Oncol 2010; 5:169-78. [PMID: 20035238 DOI: 10.1097/jto.0b013e3181c8cbd9] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
INTRODUCTION Serum proteomics and mutations in the epidermal growth factor receptor (EGFR) and KRAS have been associated with benefit after therapy with EGFR-targeted therapies in non-small cell lung cancer, but all three have not been evaluated in any one study. HYPOTHESIS Pretreatment serum proteomics predicts survival in Western advanced non-small cell lung cancer patients with wild-type EGFR and independent of KRAS mutation status. METHODS We analyzed available biospecimens from Eastern Cooperative Oncology Group 3503, a single-arm phase II study of erlotinib in first-line advanced lung cancer, for proteomics signatures in the previously described serum matrix-assisted laser desorption ionization proteomic classifier (VeriStrat) as well as for KRAS and EGFR mutations. RESULTS Out of 137 enrolled patients, analyzable biologic samples were available on 102. Nine of 41 (22%) demonstrated KRAS mutations and 3 of 41 (7%) harbored EGFR mutations. VeriStrat classification identified 64 of 88 (73%) as predicted to have "good" and 24 of 88 (27%) predicted to have "poor" outcomes. A statistically significant correlation of VeriStrat status (p < 0.001) was found with survival. EGFR mutations, but not KRAS mutations, also correlated with survival. CONCLUSIONS The previously defined matrix-assisted laser desorption ionization predictor remains a potent and highly clinically significant predictor of survival after first-line treatment with erlotinib in patients with wild-type EGFR and independent of mutations in KRAS.
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Affiliation(s)
- Joseph M Amann
- Department of Cancer Biology, Vanderbilt University, Nashville, Tennessee, USA
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2455
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Kolligs FT. Conference scene: DGVS spring conference 2009. Biomark Med 2010; 3:573-5. [PMID: 20477525 DOI: 10.2217/bmm.09.44] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The 3rd annual DGVS Spring Conference of the German Society for Gastroenterology (Deutsche Gesellschaft für Verdauungs- und Stoffwechselkrankheiten) was held at the Seminaris Campus Hotel in Berlin, Germany, on 8-9 May, 2009. The conference was organized by Roland Schmid and Matthias Ebert from the Technical University of Munich, Germany. The central theme of the meeting was 'translational gastrointestinal oncology: towards personalized medicine and individualized therapy'. The conference covered talks on markers for diagnosis, screening and surveillance of colorectal cancer, targets for molecular therapy, response prediction in clinical oncology, development and integration of molecular imaging in gastrointestinal oncology and translational research in clinical trial design. Owing to the broad array of topics and limitations of space, this article will focus on biomarkers, response prediction and the integration of biomarkers into clinical trials. Presentations mentioned in this summary were given by Matthias Ebert (Technical University of Munich, Germany), Esmeralda Heiden (Epigenomics, Berlin, Germany), Frank Kolligs (University of Munich, Germany), Florian Lordick (University of Heidelberg, Germany), Hans Jorgen Nielsen (University of Copenhagen, Denmark), Anke Reinacher-Schick (University of Bochum, Germany), Christoph Röcken (University of Berlin, Germany), Wolff Schmiegel (University of Bochum, Germany) and Thomas Seufferlein (University of Halle, Germany).
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Affiliation(s)
- Frank Thomas Kolligs
- Department of Medicine II, University of Munich, Marchioninistrasse 15, 81377 Munich, Germany.
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2456
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Abstract
Epidermal growth factor is a 170-kd protein that binds to a specific tyrosine kinase receptor, epidermal growth factor receptor (EGFR), on the cell surface. EGFR function is dysregulated in various malignancies including nonsmall cell lung cancer (NSCLC) leading to activation of several signal transduction pathways including K-RAS, PIK3, and STAT3 and STAT5, that promote cell cycle progression, proliferation, invasion, angiogenesis, and inhibit apoptosis. EGFR overexpression is seen in a majority of cases of NSCLC, but its prognostic role is controversial. EGFR inhibitors currently undergoing clinical trials in NSCLC include monoclonal antibodies or small molecule tyrosine kinase inhibitors. The only EGFR inhibitor currently approved for the treatment of NSCLC is erlotinib, a small molecule tyrosine kinase inhibitor. Although women, nonsmokers, patients with adenocarcinoma and patients with Asian ethnicity seem to have better outcomes with erlotinib, the factors predictive for response to these agents are currently the focus of investigation.
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Abstract
Cancer chemotherapy is in evolution from non-specific cytotoxic drugs that damage both tumour and normal cells to more specific agents and immunotherapy approaches. Targeted agents are directed at unique molecular features of cancer cells, and immunotherapeutics modulate the tumour immune response; both approaches aim to produce greater effectiveness with less toxicity. The development and use of such agents in biomarker-defined populations enables a more personalized approach to cancer treatment than previously possible and has the potential to reduce the cost of cancer care.
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Affiliation(s)
- Richard L Schilsky
- Comprehensive Cancer Center, University of Chicago, 5841 South Maryland Avenue, MC 2115, Chicago, IL 60637, USA.
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2458
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Tol J, Dijkstra JR, Vink-Börger ME, Nagtegaal ID, Punt CJA, Van Krieken JHJM, Ligtenberg MJL. High sensitivity of both sequencing and real-time PCR analysis of KRAS mutations in colorectal cancer tissue. J Cell Mol Med 2010; 14:2122-31. [PMID: 19453520 PMCID: PMC3823003 DOI: 10.1111/j.1582-4934.2009.00788.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The KRAS mutation status predicts the outcome of treatment with epidermal growth factor receptor targeted agents, and therefore the testing for KRAS mutations has become an important diagnostic procedure. To optimize the quality of this test, we compared the results of the two most commonly used KRAS mutation tests, cycle sequencing and a real-time PCR-based assay, in DNA extracted from formalin-fixed paraffin-embedded (FFPE) colorectal cancer samples of 511 patients. The results were interpreted in the context of the tumour cell percentage and the assay parameters. In 510 samples KRAS mutation status assessment was successful. A KRAS mutation was detected in 201 tumours (39.4%). Sequencing and the real-time PCR-based assay generated the same result in 486 samples (95.3%). The sequencing result was considered false positive in one (0.2%) and false negative in nine samples (1.8%). The assay result was considered false positive in six (1.2%) and false negative in seven samples (1.4%). Explanations for discrepant test results were a higher sensitivity of the assay in samples with a low tumour cell percentage, occurrence of mutations that are not covered by the assay and δ Ct values approximating the cut-off value of the assay. In conclusion, both sequencing and the real-time PCR-based assay are reliable tests for KRAS mutation analysis in FFPE colorectal cancer samples, with a sensitivity of 95.5% (95% confidence interval [CI] 91.7–97.9%) and 96.5% (95% CI 93.0–98.6%), respectively. The real-time PCR based assay is the method of choice in samples with a tumour cell percentage below 30%.
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Affiliation(s)
- Jolien Tol
- Department of Medical Oncology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
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2459
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Prenen H, Tejpar S, Van Cutsem E. New strategies for treatment of KRAS mutant metastatic colorectal cancer. Clin Cancer Res 2010; 16:2921-6. [PMID: 20460490 DOI: 10.1158/1078-0432.ccr-09-2029] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The introduction of new cytotoxic agents and new targeted therapies has significantly broadened the therapeutic options for and the outcomes of patients with metastatic colorectal cancer (CRC). The introduction of the anti-epidermal growth factor receptor (EGFR) antibodies, cetuximab and panitumumab, has clearly contributed to this development. The concept of KRAS as a marker for resistance to anti-EGFR antibodies has been validated. However, new challenges have emerged: the complete understanding of the crucial and central role of KRAS in processes of tumor growth and the development of new treatment strategies for KRAS mutant tumors. KRAS seems to be so crucial that a further classification and description in KRAS wild-type and mutant may be warranted. Testing for KRAS mutations marks, therefore, a paradigm shift in the management of metastatic CRC. This testing also highlights the unmet need for new treatment options in KRAS mutant metastatic CRC. In this review we will focus on possible new treatment options for these patients.
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Affiliation(s)
- Hans Prenen
- Department of Digestive Oncology, University Hospital Gasthuisberg/Leuven, Belgium
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2460
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Berger ML, Eck S, Ruberg SJ. Raising the bar of efficacy for drug approval requires an understanding of patient diversity. J Clin Oncol 2010; 28:e343-4; author reply e345. [PMID: 20458030 DOI: 10.1200/jco.2010.28.2475] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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2461
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Choi HJ, Sohn JH, Lee CG, Shim HS, Lee IJ, Yang WI, Kwon JE, Kim SK, Park MS, Lee JH, Kim JH. A phase I study of nimotuzumab in combination with radiotherapy in stages IIB-IV non-small cell lung cancer unsuitable for radical therapy: Korean results. Lung Cancer 2010; 71:55-9. [PMID: 20451284 DOI: 10.1016/j.lungcan.2010.04.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 04/05/2010] [Accepted: 04/06/2010] [Indexed: 12/01/2022]
Abstract
PURPOSE This study was undertaken to determine safety and tolerability of nimotuzumab, a humanized anti-epidermal growth factor receptor monoclonal antibody, in combination with radiotherapy in stages IIB-IV non-small cell lung cancer (NSCLC) patients who are unsuitable for radical therapy or chemotherapy. METHODS Nimotuzumab (100mg, 200mg and 400mg) was administered weekly from week 1 to week 8 with palliative radiotherapy (30-36 Gy, 3 Gy/day). If tumor control was achieved, nimotuzumab was continued every 2 weeks until unacceptable toxicity or disease progression. Serial skin biopsies were collected for pharmacodynamic assessment. RESULTS Fifteen patients were enrolled in the study, with cohorts of five patients assigned in each dose level of nimotuzumab. Patients and disease characteristics included median age 73 years; Eastern Cooperative Oncology Group performance status (PS) 0-1/2 (n=3/12); female sex (n=2); adenocarcinoma (n=5); never-smoker status (n=2); and stages IIB/IIIB/IV (n=1/8/6). All patients were unable to tolerate radical therapy because of old age or multiple comorbidities. The most commonly reported adverse events were lymphopenia and asthenia (grades 1-2 in most patients). No skin rash or allergic toxicities appeared. Dose-limiting toxicity occurred with pneumonia with grade 4 neutropenia at the 200mg dose of nimotuzumab. Objective response rate and disease control rate inside the radiation field were 46.7% and 100.0%, respectively. CONCLUSIONS Nimotuzumab in combination with radiotherapy is well-tolerated and feasible. Further clinical investigation of nimotuzumab in NSCLC patients is warranted.
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Affiliation(s)
- Hye Jin Choi
- Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
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2462
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Villanueva A, Minguez B, Forner A, Reig M, Llovet JM. Hepatocellular carcinoma: novel molecular approaches for diagnosis, prognosis, and therapy. Annu Rev Med 2010; 61:317-28. [PMID: 20059340 DOI: 10.1146/annurev.med.080608.100623] [Citation(s) in RCA: 192] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The genomic era is changing the understanding of cancer, although translation of the vast amount of data available into decision-making algorithms is far from reality. Molecular profiling of hepatocellular carcinoma (HCC), the most common cause of death among cirrhotic patients and a fast-growing malignancy in Western countries, is enabling the advancement of novel approaches to disease diagnosis and management. Most HCCs arise on a cirrhotic liver, and predictably, an accurate genomic characterization will allow the identification of procarcinogenic signals amenable to selective targeting by chemopreventive strategies. Molecular diagnosis is currently feasible for small tumors, but it has not yet been formalized by scientific guidelines. Molecular treatment is a reality: Sorafenib confers unprecedented survival benefits in patients at advanced stages. Genomic information from tumor and nontumoral tissue will aid prognosis prediction and facilitate the identification of oncogene addiction loops, providing the opportunity for more personalized medicine.
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Affiliation(s)
- Augusto Villanueva
- HCC Translational Research Laboratory, Barcelona-Clínic Liver Cancer Group, Institut d'Investigacions Biomediques Agusto Pi i Sunyer (IDIBAPS), Liver Unit, Hospital Clinic, Barcelona, Spain.
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2463
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Gangadhar T, Schilsky RL. Molecular markers to individualize adjuvant therapy for colon cancer. Nat Rev Clin Oncol 2010; 7:318-25. [PMID: 20440283 DOI: 10.1038/nrclinonc.2010.62] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
While many patients with early-stage colon cancer are cured with surgery alone, the standard of care remains a uniform approach to adjuvant chemotherapy based primarily on tumor stage. Recently, increasing awareness of the need for more individualized decision-making in cancer care has led to the development of several potential prognostic and predictive markers in colon cancer. While adjuvant chemotherapy with 5-fluorouracil, leucovorin and oxaliplatin is clearly beneficial to patients with stage III disease, well-validated molecular markers might help define which patients with stage II disease are likely to benefit from adjuvant therapy as well. Here, we review the data on the clinical development of molecular markers to individualize adjuvant therapy in colon cancer.
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Affiliation(s)
- Tara Gangadhar
- Section of Hematology-Oncology and Comprehensive Cancer Center, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA
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2464
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Socinski MA. The Emerging Role of Biomarkers in Advanced Non–Small-Cell Lung Cancer. Clin Lung Cancer 2010; 11:149-59. [DOI: 10.3816/clc.2010.n.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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2465
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2466
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Colon cancer. Crit Rev Oncol Hematol 2010; 74:106-33. [DOI: 10.1016/j.critrevonc.2010.01.010] [Citation(s) in RCA: 194] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 09/30/2009] [Accepted: 01/06/2010] [Indexed: 12/15/2022] Open
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2467
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Spigel DR, Greco FA, Thompson DS, Webb C, Rubinsak J, Inhorn RC, Reeves J, Vazquez ER, Lane CM, Burris HA, Hainsworth JD. Phase II Study of Cetuximab, Docetaxel, and Gemcitabine in Patients With Previously Untreated Advanced Non–Small-Cell Lung Cancer. Clin Lung Cancer 2010; 11:198-203. [DOI: 10.3816/clc.2010.n.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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2468
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Amosenko FA, Korchagina EL, Matveeva TI, Vaganov YE, Vlasov SB, Poltavets NV, Veselov VV, Garkavtseva RF, Polyakov AV. Mutation analysis of K-ras protooncogene in colorectal adenocarcinomas and polyps in Russian patients. RUSS J GENET+ 2010. [DOI: 10.1134/s1022795410050169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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2469
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Schlaeth M, Berger S, Derer S, Klausz K, Lohse S, Dechant M, Lazar GA, Schneider-Merck T, Peipp M, Valerius T. Fc-engineered EGF-R antibodies mediate improved antibody-dependent cellular cytotoxicity (ADCC) against KRAS-mutated tumor cells. Cancer Sci 2010; 101:1080-8. [PMID: 20331636 PMCID: PMC11158590 DOI: 10.1111/j.1349-7006.2010.01505.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Oncogenic mutations of the KRAS gene have emerged as a common mechanism of resistance against epidermal growth factor receptor (EGF-R)-directed tumor therapy. Mutated KRAS leads to ligand-independent activation of signaling pathways downstream of EGF-R. Thereby, direct effector mechanisms of EGF-R antibodies, such as blockade of ligand binding and inhibition of signaling, are bypassed. Thus, a humanized variant of the approved EGF-R antibody Cetuximab inhibited growth of wild-type KRAS-expressing A431 cells, but did not inhibit KRAS-mutated A549 tumor cells. We then investigated whether killing of tumor cells harboring mutated KRAS can be improved by enhancing antibody-dependent cellular cytotoxicity (ADCC). Protein- and glyco-engineering of antibodies' Fc region are established technologies to enhance ADCC by increasing antibodies' affinity to activating Fcgamma receptors. Thus, EGF-R antibody variants with increased affinity for the natural killer (NK) cell-expressed FcgammaRIIIa (CD16) were generated and analyzed. These variants triggered significantly enhanced mononuclear cell (MNC)-mediated killing of KRAS-mutated tumor cells compared to wild-type antibodies. Additionally, cells transfected with mutated KRAS were killed as effectively by ADCC as vector-transfected control cells. Together, these data demonstrate that KRAS mutations are not sufficient to render tumor cells resistant to ADCC. Consequently Fc-engineered EGF-R antibodies may prove effective against KRAS-mutated tumors, which are not susceptible to signaling inhibition by EGF-R antibodies.
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Affiliation(s)
- Martin Schlaeth
- Section for Stem Cell Transplantation and Immunotherapy, Christian-Albrechts-University and University Hospital Schleswig-Holstein, Kiel, Germany
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2470
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Tsiatis AC, Norris-Kirby A, Rich RG, Hafez MJ, Gocke CD, Eshleman JR, Murphy KM. Comparison of Sanger sequencing, pyrosequencing, and melting curve analysis for the detection of KRAS mutations: diagnostic and clinical implications. J Mol Diagn 2010; 12:425-32. [PMID: 20431034 DOI: 10.2353/jmoldx.2010.090188] [Citation(s) in RCA: 363] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Mutations in codons 12 and 13 of the KRAS oncogene are relatively common in colorectal and lung adenocarcinomas. Recent data indicate that these mutations result in resistance to anti-epidermal growth factor receptor therapy. Therefore, we assessed Sanger sequencing, pyrosequencing, and melting curve analysis for the detection of KRAS codon 12/13 mutations in formalin-fixed paraffin-embedded samples, including 58 primary and 42 metastatic colorectal adenocarcinomas, 63 primary and 17 metastatic lung adenocarcinomas, and 20 normal colon samples. Of 180 tumor samples, 62.2% were KRAS mutant positive, and 37.8% were negative. Melting curve analysis yielded no false positive or false negative results, but had 10% equivocal calls. Melting curve analysis also resulted in 4 cases with melting curves inconsistent with either wild-type or codon 12/13 mutations. These patterns were generated from samples with double mutants in codons 12/13 and with mutations outside of codons 12/13. Pyrosequencing yielded no false positive or false negative results as well. However, two samples from one patient yielded a pyrogram that was flagged as abnormal, but the mutation subtype could not be determined. Finally, using an electronic cutoff of 10%, Sanger sequencing showed 11.1% false positives and 6.1% false negatives. In our hands, the limit of detection for Sanger sequencing, pyrosequencing, and melting curve analysis was approximately 15 to 20%, 5%, and 10% mutant alleles, respectively.
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Affiliation(s)
- Athanasios C Tsiatis
- The Johns Hopkins Medical Institutions, Department of Pathology, 600 N. Wolfe Street, Park SB202, Baltimore, MD 21287, USA.
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2471
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Wadlow RC, Ryan DP. The role of targeted agents in preoperative chemoradiation for rectal cancer. Cancer 2010; 116:3537-48. [DOI: 10.1002/cncr.25155] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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2472
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Markman B, Rodríguez-Freixinos V, Tabernero J. Biomarkers in colorectal cancer. Clin Transl Oncol 2010; 12:261-70. [DOI: 10.1007/s12094-010-0502-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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2473
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Debucquoy A, Machiels JP, McBride WH, Haustermans K. Integration of Epidermal Growth Factor Receptor Inhibitors with Preoperative Chemoradiation: Fig. 1. Clin Cancer Res 2010; 16:2709-14. [DOI: 10.1158/1078-0432.ccr-09-1622] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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2474
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Fornaro L, Masi G, Loupakis F, Vasile E, Falcone A. Palliative treatment of unresectable metastatic colorectal cancer. Expert Opin Pharmacother 2010; 11:63-77. [PMID: 20001430 DOI: 10.1517/14656560903427997] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
IMPORTANCE OF THE FIELD Treatment options for metastatic colorectal cancer (mCRC) patients have rapidly increased in the past years, but 50 - 70% of mCRC patients are still unlikely to undergo radical resection of metastases and are candidates for palliative therapy only. AREAS COVERED IN THIS REVIEW Oxaliplatin and irinotecan have widened the chemotherapy alternatives available in this setting and effective targeted agents against vascular endothelial growth factor and epidermal growth factor receptor have further improved treatment efficacy. This review covers the main areas of debate in the optimal treatment of unresectable mCRC patients, focusing on the implications for everyday clinical practice and future research of the most relevant clinical trials and molecular investigations published from 1999 to 2009. WHAT THE READER WILL GAIN Insights into treatment individualization strategies are provided in the review. TAKE HOME MESSAGE 'One size fits all' can not longer be considered an adequate approach to unresectable mCRC, and treatment with both chemotherapy and biologic agents should be guided by prognostic and predictive factors in order to maximize the benefit while reducing futile toxicities.
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Affiliation(s)
- Lorenzo Fornaro
- Azienda Ospedaliero-Universitaria Pisana, Istituto Toscano Tumori, Medical Oncology Unit 2, Italy
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2475
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Quantitative methodology using CT for predicting survival in patients with metastatic colorectal carcinoma: a pilot study. Clin Imaging 2010; 34:196-202. [PMID: 20416484 DOI: 10.1016/j.clinimag.2010.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 01/02/2010] [Accepted: 01/10/2010] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To develop a methodology which quantifies multiple changing lesion features resulting in an optimized computed tomography (CT) response score (CRS) for prediction of overall survival (OS) in response to treatment for metastatic colorectal carcinoma (MCRC). SUBJECTS AND METHODS This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved retrospective study evaluated multiple changing imaging findings and their correlation with OS with a new methodology comparing the baseline and first post-treatment CT scans in 38 MCRC patients on last-line chemotherapy (cetuximab and irinotecan). Tumor size/enhancement changes and interval development of new lesions were quantified with either Likert-type scales (all parameters) or Response Evaluation Criteria in Solid Tumors (RECIST) (size change only). The most predictive parameters for OS were used to generate the CRS with an overall range of -3 (complete disappearance) to +2 (definite tumor increase). The Cox Hazard Ratio was used to assess prediction of survival. Reader agreement was evaluated by the kappa statistic. RESULTS Tumor size was the best predictor of OS using the Likert-type scale or RECIST. The CRS was not improved combining size change with other parameters. Use of the Likert-type scale resulted in predicting OS with a Cox hazard ratio of 1.697 (P=.0004) and good agreement (kappa=0.73, 95% CI=0.41-1.10) between observers with no significant difference using RECIST. CONCLUSION The methodology produces a CRS for MCRC predicting OS resulting from therapy which expands standard RECIST guidelines to allow critical evaluation of multiple additional imaging parameters. Size change alone was found to be the best parameter of those considered in terms of maximizing agreement and prediction of OS.
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2476
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Abstract
Cetuximab, a chimeric IgG(1) monoclonal antibody directed against the ligand-binding domain of the epidermal growth factor receptor, offers a paradigm for the combination of molecularly targeted therapies with cytotoxic agents. In preclinical models, the addition of cetuximab to chemotherapy or radiation therapy enhances antitumor activity. Proposed mechanisms include reducing tumor cell proliferation, angiogenesis, and DNA repair capacity; increasing apoptosis; and inducing cell cycle arrest at treatment-sensitive points. These effects may enhance and restore tumor sensitivity to cytotoxic therapies. In clinical trials, the addition of cetuximab to chemotherapy improves outcomes of patients who had previously failed such agents, as illustrated in irinotecan-resistant and oxaliplatin-refractory metastatic colorectal cancer. As initial therapy, the addition of cetuximab to chemotherapy extends survival in colorectal cancer, lung cancer, and head and neck cancer. Combining cetuximab with radiation therapy extends survival in locally advanced head and neck cancer. As predictive biomarkers are identified, it may become possible to select patients most likely to benefit from such combinations.
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Affiliation(s)
- David E Gerber
- Division of Hematology-Oncology, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Mail Code 8852, Dallas, TX, 75390-8852, USA.
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Sundvall M, Karrila A, Nordberg J, Grénman R, Elenius K. EGFR targeting drugs in the treatment of head and neck squamous cell carcinoma. Expert Opin Emerg Drugs 2010; 15:185-201. [DOI: 10.1517/14728211003716442] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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2478
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Puvvada SD, Funkhouser WK, Greene K, Deal A, Chu H, Baldwin AS, Tepper JE, O'Neil BH. NF-kB and Bcl-3 activation are prognostic in metastatic colorectal cancer. Oncology 2010; 78:181-8. [PMID: 20414006 DOI: 10.1159/000313697] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 11/04/2009] [Indexed: 12/25/2022]
Abstract
PURPOSE NF-kappaB is an antiapoptotic transcription factor that has been shown to be a mediator of treatment resistance. Bcl-3 is a regulator of NF-kappaB that may play a role in oncogenesis. The goal of this study was to correlate the activation status of NF-kappaB and Bcl-3 with clinical outcome in a group of patients with metastatic colorectal cancer (CRC). METHODS A retrospective study of 23 patients who underwent surgical resection of CRC at the University of North Carolina (UNC). Activation of NF-kappaB was defined by nuclear expression of select components of NF-kappaB (p50, p52, p65) and Bcl-3. Tissue microarrays were created from cores of normal mucosa, primary tumor, lymph node metastases and liver metastases in triplicate from disparate areas of the blocks, and an intensity score was generated by multiplying intensity (0-3+) by percent of positive tumor cells. Generalized estimating equations were used to note differences in intensity scores among normal mucosa and nonnormal tissues. Cox regression models were fit to see if scores were significantly associated with overall survival. RESULTS p65 NE was significantly higher in primary tumor and liver metastases than normal mucosa (both p < 0.01). p50 nuclear expression was significantly higher for all tumor sites than for normal mucosa (primary tumor and lymph node metastases p < 0.0001, liver metastases p < 0.01). Bcl-3 nuclear expression did not differ significantly between normal mucosa and tumor; however, nuclear expression in primary tumor for each of these components was strongly associated with survival: the increase in hazard for each 50-point increase in nuclear expression was 91% for Bcl-3, 66% for p65, and 52% for p50 (all p < 0.05). CONCLUSIONS Activation of canonical NF-kappaB subunits p50 and p65 as measured by nuclear expression is strongly associated with survival suggesting NF-kappaB as a prognostic factor in this disease. Primary tumor nuclear expression appears to be as good as, or better than, metastatic sites at predicting prognosis. Bcl-3 nuclear expression is also negatively associated with survival and deserves further study in CRC.
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Affiliation(s)
- Soham D Puvvada
- Department of Internal Medicine, Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27599-7305, USA
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2479
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Retargeted adenoviral cancer gene therapy for tumour cells overexpressing epidermal growth factor receptor or urokinase-type plasminogen activator receptor. Gene Ther 2010; 17:1000-10. [PMID: 20410926 DOI: 10.1038/gt.2010.45] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have assessed the ability of bispecific fusion proteins to improve adenovirus-mediated transfer of therapeutic and marker transgenes. We constructed an expression vector that can be easily modified to synthesize a variety of fusion proteins for retargeting adenoviral gene therapy vectors to cell surface markers, which are differentially expressed between normal and cancer cells. Adenoviral transduction can be improved in a number of tumour cell lines which overexpress EGFR (epidermal growth factor receptor) or uPAR (urokinase-type plasminogen activator receptor), but which have only low levels of endogenous hCAR (human coxsackie B and adenovirus receptor) expression. Up to 40-fold improvement in beta-galactosidase transgene expression was seen using an EGFR retargeting protein, and up to 16-fold using a second fusion protein targeting uPAR. In vitro, our uPAR retargeting fusion protein improved the sensitivity to adenoviral herpes simplex virus thymidine kinase/ganciclovir by an order of magnitude, whereas in vivo, our EGFR retargeting protein is able to significantly delay tumour growth in rodent animal models in a dose-dependent manner. The 'cassette' design of our fusion protein constructs offers a flexible method for the straightforward synthesis of multiple adenoviral retargeting proteins, directed against a variety of tumour-associated antigens, for use in clinical trials.
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2480
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Potti A, Schilsky RL, Nevins JR. Refocusing the War on Cancer: The Critical Role of Personalized Treatment. Sci Transl Med 2010; 2:28cm13. [DOI: 10.1126/scitranslmed.3000643] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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2481
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Tol J, Dijkstra JR, Klomp M, Teerenstra S, Dommerholt M, Vink-Börger ME, van Cleef PH, van Krieken JH, Punt CJA, Nagtegaal ID. Markers for EGFR pathway activation as predictor of outcome in metastatic colorectal cancer patients treated with or without cetuximab. Eur J Cancer 2010; 46:1997-2009. [PMID: 20413299 DOI: 10.1016/j.ejca.2010.03.036] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Accepted: 03/29/2010] [Indexed: 02/06/2023]
Abstract
BACKGROUND Anti-EGFR monoclonal antibodies in metastatic colorectal cancer (mCRC) treatment are only effective in patients with KRAS wild type tumours. Here we assess the predictive value of other potential relevant markers involved in the epidermal growth factor receptor (EGFR) signalling pathways for response to cetuximab-based treatment. MATERIALS AND METHODS Formalin-fixed paraffin-embedded colorectal cancer tissue of the primary tumour was obtained from 559 mCRC patients treated with chemotherapy and bevacizumab with or without cetuximab (phase III CAIRO2 study). DNA was isolated for mutation analysis of BRAF (V600E), KRAS (codon 12 and 13) and PIK3CA (exon 9 and 20). Tissue microarray's (TMA's) were constructed for the assessment of EGFR and HER2 gene copy number (GCN), and EGFR and PTEN protein expression. The results of these markers, individually or in combination, were correlated with progression-free survival (PFS) and overall survival (OS) in the subgroup of patients with a KRAS wild type tumour treated in the cetuximab-arm. KRAS wild type patients treated without cetuximab were used as a control group. RESULTS A total of 208 tumours (39.4%) contained a KRAS mutation, 8.7% a BRAF mutation and 9.9% a PIK3CA mutation. Loss of PTEN expression and the presence EGFR protein expression were observed in 42.0% and 61.7% of the samples, respectively. An increased EGFR GCN was observed in 15.3% of the samples, and 11.5% of the evaluable samples contained an increased HER2 GCN. In KRAS wild type patients treated with cetuximab a BRAF mutation was significantly and independently associated with PFS and OS. In patients treated without cetuximab the PFS and OS were also associated with the BRAF genotype. No prognostic or predictive value was observed for any of the other markers when tested individually or in combination. CONCLUSIONS BRAF genotype is correlated with PFS and OS in KRAS wild type mCRC patients, which is independent of cetuximab treatment. PIK3CA mutation, loss of PTEN expression, EGFR GCN and HER2 GCN have no predictive value for response to treatment with cetuximab, neither individually nor in combination with other markers.
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Affiliation(s)
- Jolien Tol
- Department of Medical Oncology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
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2482
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Jakubauskas A, Griskevicius L. KRas and BRaf mutational status analysis from formalin-fixed, paraffin-embedded tissues using multiplex polymerase chain reaction-based assay. Arch Pathol Lab Med 2010; 134:620-4. [PMID: 20367313 DOI: 10.5858/134.4.620] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
CONTEXT Monoclonal anti-epidermal growth factor receptor antibodies bind to the epidermal growth factor receptor and inhibit receptor kinase activity. Clinical trials have indicated that evaluation of the mutational status of KRas and BRaf is necessary to exclude patients who are resistant to the clinical benefit of anti-epidermal growth factor receptor therapy. OBJECTIVE To develop a multiplex polymerase chain reaction-based assay for the evaluation of KRas and BRaf mutational status. DESIGN A sample-saving and cost-effective, multiplex polymerase chain reaction-based assay to detect somatic mutations in KRAS exon 2 and exon 3 as well as in BRAF exon 15 was developed. The same primer pairs could be successfully used in amplification of a single DNA fragment under the same conditions. RESULTS DNA isolated from 20 retrospective formalin-fixed, paraffin-embedded samples of colorectal cancer was screened for mutations using the multiplex polymerase chain reaction assay followed by dideoxy-termination sequencing. Five samples bearing mutations-p.G12D (identified twice), p.G12V, p.G12S, and p.G13D, all encoded in KRAS exon 2-were identified. Three samples were found bearing amino acid substitution p.V600E of BRaf. The detected KRas and BRaf mutations were found to be mutually exclusive. CONCLUSIONS A multiplex polymerase chain reaction-based amplification followed by dideoxy-termination sequencing may be used advantageously for the evaluation of KRas and BRaf mutational status from formalin-fixed, paraffin-embedded samples.
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Affiliation(s)
- Arturas Jakubauskas
- Department of Molecular and Regenerative Medicine, Oncology and Transfusion Medicine Center, Vilnius University Hospital, Santariskiu Clinics, Lithuania.
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2483
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Campanella C, Mottolese M, Cianciulli A, Torsello A, Merola R, Sperduti I, Melucci E, Conti S, Diodoro MG, Zeuli M, Paoletti G, Cognetti F, Garufi C. Epidermal growth factor receptor gene copy number in 101 advanced colorectal cancer patients treated with chemotherapy plus cetuximab. J Transl Med 2010; 8:36. [PMID: 20398370 PMCID: PMC2867799 DOI: 10.1186/1479-5876-8-36] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 04/16/2010] [Indexed: 11/10/2022] Open
Abstract
Background Responsiveness to Cetuximab alone can be mediated by an increase of Epidermal Growth factor Receptor (EGFR) Gene Copy Number (GCN). Aim of this study was to assess the role of EGFR-GCN in advanced colorectal cancer (CRC) patients receiving chemotherapy plus Cetuximab. Methods One hundred and one advanced CRC patients (43 untreated- and 58 pre-treated) were retrospectively studied by fluorescence in situ hybridization (FISH) to assess EGFR-GCN and by immunohistochemistry (IHC) to determine EGFR expression. Sixty-one out of 101 patients were evaluated also for k-ras status by direct sequencing. Clinical end-points were response rate (RR), progression-free survival (PFS) and overall survival (OS). Results Increased EGFR-GCN was found in 60/101 (59%) tumor samples. There was no correlation between intensity of EGFR-IHC and EGFR-GCN (p = 0.43). Patients receiving chemotherapy plus Cetuximab as first line treatment had a RR of 70% (30/43) while it was 18% (10/56) in the group with previous lines of therapy (p < 0.0001). RR was observed in 29/60 (48%) of patients with increased EGFR-GCN and in 6/28 (21%) in those without (p = 0.02). At multivariate analyses, number of chemotherapy lines and increased EGFR-GCN were predictive of response; EGFR-IHC score, increased EGFR-GCN and number of chemotherapy lines were significantly associated with a significant better PFS. Response to therapy was the only prognostic predictive factor for OS. In the 60 patients analyzed for k-ras mutations, number of chemotherapy lines, increased EGFR-GCN and k-ras wild type status predicted a better PFS. Conclusion In metastatic CRC patients treated with chemotherapy plus Cetuximab number of chemotherapy lines and increased EGFR-GCN were significantly associated with a better clinical outcome, independent of k-ras status.
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Affiliation(s)
- Carla Campanella
- Department of Medical Oncology, Regina Elena Institute, Rome, Italy
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2484
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Abstract
As the upward spiral of novel cancer gene discoveries and novel molecular compounds continues to accelerate, a repetitive theme in molecular drug development remains the lack of activity of initially promising agents when given to patients in clinical trials. It is however invigorating that a few targeted agents directed against a select group of a few 'cancer gene superfamilies' have escaped this all to common fate, and have evolved into novel, clinically meaningful molecular therapy strategies. Targeting dysregulated signaling of the epidermal growth factor family of transmembrane receptors (Erbb family) has encompassed over the last decade an ever increasing role in personalized treatment approaches in an increasing number of human malignancies. Erbbs are receptor tyrosine kinases that are important regulators of several signaling pathways. Two of its family members (Erbb1/EGFR and Erbb2/HER2) have previously been shown to be somatically mutated in large fraction of human cancers. To determine if this family is somatically mutated in melanoma, its sequences were recently analyzed and one of its members, Erbb4, was found to be somatically mutated in 19% of melanoma cases. Functional analysis of seven of its mutations was shown to increase its catalytic and transformation abilities as well as providing essential survival signals. Similar to other Erbb family members, mutant Erbb4 seems to confer 'oncogene addiction' on melanoma cells, making it an attractive therapeutic target. Gaining further understanding into the oncogenic mechanism of Erbb4 may not only help in the development of targeted therapy in melanoma patients but might accelerate the acceptance of a novel taxonomy of cancer which is based on the genomic perturbations in cancer genes and cancer gene families and their response to targeted agents.
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Affiliation(s)
- Udo Rudloff
- National Cancer Institute, Surgery Branch, Bethesda, MD USA
| | - Yardena Samuels
- National Human Genome Research Institute, Cancer Genetics Branch, Bethesda, MD USA
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Mandrekar SJ, Sargent DJ. Predictive biomarker validation in practice: lessons from real trials. Clin Trials 2010; 7:567-73. [PMID: 20392785 DOI: 10.1177/1740774510368574] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND With the advent of targeted therapies, biomarkers provide a promising means of individualizing therapy through an integrated approach to prediction using the genetic makeup of the disease and the genotype of the patient. Biomarker validation has therefore become a central topic of discussion in the field of medicine, primarily due to the changing landscape of therapies for treatment of a disease and these therapies purported mechanism(s) of action. PURPOSE In this report, we discuss the merits and limitations of some of the clinical trial designs for predictive biomarker validation using examples from ongoing or completed clinical trials. METHODS The designs are broadly classified as retrospective (i.e., using data from previously well-conducted randomized controlled trials (RCT)) versus prospective (enrichment or targeted, unselected or all-comers, hybrid, and adaptive analysis). We discuss some of these designs in the context of real trials. RESULTS Well-designed retrospective analysis of prospective RCT can bring forward effective treatments to marker defined subgroup of patients in a timely manner. An example is the KRAS gene status in colorectal cancer - the benefit from cetuximab and panitumumab was demonstrated to be restricted to patients with wild type status based on prospectively specified analyses using data from previously conducted RCTs. Prospective enrichment designs are appropriate when compelling preliminary evidence suggests that not all patients will benefit from the study treatment under consideration; however, this may sometimes leave questions unanswered. An example is the established benefit of trastuzumab as adjuvant therapy for breast cancer; a clear definition of HER2-positivity and the assay reproducibility have, however, remained unanswered. An all-comers design is optimal where preliminary evidence regarding treatment benefit and assay reproducibility is uncertain (e.g., EGFR expression and tyrosine kinase inhibitors in lung cancer), or to identify the most effective therapy from a panel of regimens (e.g., chemotherapy options in breast cancer). LIMITATIONS The designs discussed here rest on the assumption that the technical feasibility, assay performance metrics, and the logistics of specimen collection are well established and that initial results demonstrate promise with regard to the predictive ability of the marker(s). CONCLUSIONS The choice of a clinical trial design is driven by a combination of scientific, clinical, statistical, and ethical considerations. There is no one size fits all solution to predictive biomarker validation.
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Affiliation(s)
- Sumithra J Mandrekar
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905, USA.
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2486
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Sánchez-Muñoz A, Gallego E, de Luque V, Pérez-Rivas LG, Vicioso L, Ribelles N, Lozano J, Alba E. Lack of evidence for KRAS oncogenic mutations in triple-negative breast cancer. BMC Cancer 2010; 10:136. [PMID: 20385028 PMCID: PMC2868051 DOI: 10.1186/1471-2407-10-136] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Accepted: 04/13/2010] [Indexed: 12/17/2022] Open
Abstract
Background Mutational analysis of the KRAS gene has recently been established as a complementary in vitro diagnostic tool for the identification of patients with colorectal cancer who will not benefit from anti-epidermal growth factor receptor (EGFR) therapies. Assessment of the mutation status of KRAS might also be of potential relevance in other EGFR-overexpressing tumors, such as those occurring in breast cancer. Although KRAS is mutated in only a minor fraction of breast tumors (5%), about 60% of the basal-like subtype express EGFR and, therefore could be targeted by EGFR inhibitors. We aimed to study the mutation frequency of KRAS in that subtype of breast tumors to provide a molecular basis for the evaluation of anti-EGFR therapies. Methods Total, genomic DNA was obtained from a group of 35 formalin-fixed paraffin-embedded, triple-negative breast tumor samples. Among these, 77.1% (27/35) were defined as basal-like by immunostaining specific for the established surrogate markers cytokeratin (CK) 5/6 and/or EGFR. KRAS mutational status was determined in the purified DNA samples by Real Time (RT)-PCR using primers specific for the detection of wild-type KRAS or the following seven oncogenic somatic mutations: Gly12Ala, Gly12Asp, Gly12Arg, Gly12Cys, Gly12Ser, Gly12Val and Gly13Asp. Results We found no evidence of KRAS oncogenic mutations in all analyzed tumors. Conclusions This study indicates that KRAS mutations are very infrequent in triple-negative breast tumors and that EGFR inhibitors may be of potential benefit in the treatment of basal-like breast tumors, which overexpress EGFR in about 60% of all cases.
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Affiliation(s)
- Alfonso Sánchez-Muñoz
- Servicio de Oncología Médica, Hospital Universitario Virgen de Victoria, Campus de Teatinos s/n, 29010 Málaga, Spain
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2487
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Lièvre A, Blons H, Laurent-Puig P. Oncogenic mutations as predictive factors in colorectal cancer. Oncogene 2010; 29:3033-43. [PMID: 20383189 DOI: 10.1038/onc.2010.89] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies cetuximab and panitumumab have been demonstrated to be new therapeutic options for metastatic colorectal cancer (mCRC). Oncogenic activation of intracellular signalling pathways downstream of EGFR has a major role in colorectal carcinogenesis but has also been reported to be an important mechanism of resistance to anti-EGFR antibodies. Among the activating mutations found in colorectal cancers, tumour KRAS mutations, which are found in approximately 40% of the cases, have been widely demonstrated as a major predictive marker of resistance to cetuximab or panitumumab, therefore, opening the way to individualized treatment for patients with mCRC. Other oncogenic mutations, such as BRAF or PIK3CA mutations or loss of PTEN expression, may also be additional interesting predictive markers of response to anti-EGFR monoclonal antibodies but required further evaluation before being incorporated in clinical practice. The identification of these molecular markers involved in the resistance of anti-EGFR antibodies will allow the development of new therapies that should target 'escape mechanisms' used by tumours to circumvent a pathway that has been pharmacologically blocked by anti-EGFR.
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Affiliation(s)
- A Lièvre
- INSERM UMR-S 775 Molecular Basis of Response to Xenobiotics, Paris, France
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2488
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Integrated molecular dissection of the epidermal growth factor receptor (EFGR) oncogenic pathway to predict response to EGFR-targeted monoclonal antibodies in metastatic colorectal cancer. Target Oncol 2010; 5:19-28. [DOI: 10.1007/s11523-010-0138-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 03/19/2010] [Indexed: 01/22/2023]
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2489
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Hägerstrand D, Lindh MB, Peña C, Garcia-Echeverria C, Nistér M, Hofmann F, Ostman A. PI3K/PTEN/Akt pathway status affects the sensitivity of high-grade glioma cell cultures to the insulin-like growth factor-1 receptor inhibitor NVP-AEW541. Neuro Oncol 2010; 12:967-75. [PMID: 20378689 DOI: 10.1093/neuonc/noq029] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
IGF-1 receptor signaling contributes to the growth of many solid tumors, including glioblastoma. This study analyzed the sensitivity of 8 glioblastoma cultures to the IGF-1 receptor inhibitor NVP-AEW541. Growth reduction, caused by a combination of antiproliferative and proapoptotic effects, varied between 20% and 100%. Growth-inhibitory effects of IGF-1 receptor siRNA were also demonstrated in 2 of the cultures. Activating mutations in PIK3CA were found in 2 cultures, and 2 other cultures displayed ligand-independent Akt phosphorylation. Growth inhibition was significantly reduced in cultures with PIK3CA mutations or ligand-independent Akt phosphorylation. PTEN siRNA experiments supported the notion that the status of the PI3K/PTEN/Akt pathway is involved in determining NVP-AEW541 sensitivity. Combination treatments with either PI3 kinase or mTOR inhibitors together with NVP-AEW541 were performed. These experiments demonstrated the effects of NVP-AEW541 in cells not responding to mono-treatment with the IGF-1 receptor inhibitor, when used together with either of the 2 other inhibitors. Together, the studies support continued clinical development of IGF-1 receptor antagonists for glioblastomas and identify links between PI3K/PTEN/Akt status and sensitivity to mono-treatment with NVP-AEW541. Furthermore, the studies suggest that NVP-AEW541 is also active together with PI3 kinase and mTOR inhibitors in cultures with a dysregulated PI3K/PTEN/Akt pathway. These studies should assist in future clinical development of IGF-1 receptor antagonists for glioblastoma and other tumors.
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Affiliation(s)
- Daniel Hägerstrand
- Department of Oncology-Pathology, Karolinska Institutet, Cancer Center Karolinska, Stockholm, Sweden
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2490
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Abstract
Biomarkers and surrogate end points have great potential for use in clinical oncology, but their statistical validation presents major challenges, and few biomarkers have been robustly confirmed. Provisional supportive data for prognostic biomarkers, which predict the likely outcome independently of treatment, is possible through small retrospective studies, but it has proved more difficult to achieve robust multi-site validation. Predictive biomarkers, which predict the likely response of patients to specific treatments, require more extensive data for validation, specifically large randomized clinical trials and meta-analysis. Surrogate end points are even more challenging to validate, and require data demonstrating both that the surrogate is prognostic for the true end point independently of treatment, and that the effect of treatment on the surrogate reliably predicts its effect on the true end point. In this Review, we discuss the nature of prognostic and predictive biomarkers and surrogate end points, and examine the statistical techniques and designs required for their validation. In cases where the statistical requirements for validation cannot be rigorously achieved, the biological plausibility of an end point or surrogate might support its adoption. No consensus yet exists on processes or standards for pragmatic evaluation and adoption of biomarkers and surrogate end points in the absence of robust statistical validation.
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2492
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Triano LR, Deshpande H, Gettinger SN. Management of patients with advanced non-small cell lung cancer: current and emerging options. Drugs 2010; 70:167-79. [PMID: 20108990 DOI: 10.2165/11532200-000000000-00000] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Systemic therapy for advanced non-small cell lung cancer (NSCLC) has evolved over the last two decades, with modest improvements in quality of life and overall survival. A plateau has been reached with traditional chemotherapy, and efforts are now being directed at developing molecularly targeted agents. To date, three such agents have been found to improve overall survival in advanced NSCLC. Erlotinib, a small-molecule inhibitor of the epidermal growth factor receptor, was approved by the US FDA in 2004 as second- or third-line treatment for advanced NSCLC. Bevacizumab, an antibody to vascular endothelial growth factor, a key mediator of angiogenesis, received approval in 2006, after a randomized trial reported a median survival of 1 year when bevacizumab was added to first-line chemotherapy. More recently, cetuximab, an antibody to the epidermal growth factor receptor, was found to improve outcome when added to chemotherapy, and FDA approval is anticipated. Several additional agents are currently being evaluated in randomized trials, with encouraging results from early studies. These and other studies are prospectively investigating predictive clinical and molecular characteristics, with the ultimate goal of individualizing therapy in advanced NSCLC.
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Affiliation(s)
- Laura R Triano
- Yale Cancer Center/Yale University School of Medicine, New Haven, Connecticut, USA
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2493
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Winder T, Lenz HJ. Molecular predictive and prognostic markers in colon cancer. Cancer Treat Rev 2010; 36:550-6. [PMID: 20363564 DOI: 10.1016/j.ctrv.2010.03.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 03/08/2010] [Accepted: 03/12/2010] [Indexed: 12/29/2022]
Abstract
Colorectal cancer remains one of the major cancer related death despite progress in the cytotoxic treatment of colorectal cancer (CRC) over the past decade. The introduction of targeted agents has improved the progression free and overall survival of metastatic disease. However, 40-50% of patients do not experience beneficial effects and it remains a challenge to select patients likely to respond to therapy. Several new molecular predictive and prognostic markers have been identified and are now being translated into routine clinical practice. K-Ras mutation is the first established molecular marker with a lack of response in K-Ras mutated patients treated with an epidermal growth factor receptor (EGFR)-targeted therapy. The validation of predictive and prognostic markers will result in more successful and less toxic therapeutic regimens for cancer patients. This review aims to summarize the most important currently available predictive and prognostic molecular markers in colorectal cancer.
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Affiliation(s)
- Thomas Winder
- Division of Medical Oncology, University of Southern California, Norris Comprehensive Cancer Center, Keck School of Medicine, Los Angeles, CA 90033, USA
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2494
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Zhu L, Tan X, Tu D. Testing the Homogeneity of Two Survival Functions Against a Mixture Alternative Based on Censored Data. COMMUN STAT-SIMUL C 2010. [DOI: 10.1080/03610911003637414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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2495
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Fakih MM. KRAS mutation screening in colorectal cancer: From paper to practice. Clin Colorectal Cancer 2010; 9:22-30. [PMID: 20100685 DOI: 10.3816/ccc.2010.n.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The identification of KRAS mutation status as a predictive biomarker for the activity of epidermal growth factor receptor (EGFR) inhibitors in metastatic colorectal cancer has marked a turning point in the use of these agents in the clinic. A wealth of data indicates that patients with wild-type KRAS derive meaningful clinical benefit from cetuximab in first- and second-line settings and beyond, both in combination and as a single agent, and from panitumumab as a single agent in the refractory setting. Patients with KRAS-mutant tumors do not benefit from EGFR inhibition and should not be treated with these agents. KRAS mutation testing should be part of routine standard practice, preferably at the time of diagnosis or early in the course of management. Immediate knowledge of the KRAS mutation status of a tumor allows for the optimal incorporation of anti-EGFR monoclonal antibody (MoAb) therapy where it may be most beneficial for the patient, such as in downstaging regimens outside of the refractory setting where anti-EGFR MoAb therapy is otherwise typically indicated. Available technologies make this test relatively easy to implement; archival paraffin-embedded samples from primary or metastatic sites can be used indistinctly without compromising reliability and without the need for repeated biopsies. Several diagnostic laboratories provide KRAS testing services. This powerful selection tool reduces unnecessary toxicities and costs and should be part of the standard diagnostic workup of any patient.
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Affiliation(s)
- Marwan M Fakih
- Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.
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2496
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The frequency of KRAS mutation detection in human colon carcinoma is influenced by the sensitivity of assay methodology: a comparison between direct sequencing and real-time PCR. Biochem Biophys Res Commun 2010; 395:158-62. [PMID: 20361930 DOI: 10.1016/j.bbrc.2010.03.167] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 03/27/2010] [Indexed: 11/22/2022]
Abstract
PURPOSE Kirsten rat sarcoma (KRAS) gene mutations occur early in the progression of colorectal adenoma to carcinoma. The mutation status of the KRAS gene determines the benefits of molecular targeting drugs in patients with advanced colorectal cancer, although many methods are available to detect such mutations. The purpose of this study was to evaluate the influence of assay sensitivity on the detection frequency of mutated genes. METHODS Colorectal tumors in 224 colorectal cancer patients were characterized for KRAS mutations using PCR amplification following by direct sequencing as well as a peptide nucleic acid (PNA)-clamp real-time PCR-based assay. RESULTS KRAS mutations were observed in 32.1% (72/224) patients by direct sequencing, and 43.3% (97/224) by PNA-clamp PCR. The chi-square test revealed that the difference in the frequency of KRAS mutations determined by direct sequencing and PNA-clamped PCR (threshold for 1% detection) was statistically significant (p<0.015). CONCLUSIONS Our data suggest that assay method sensitivity clearly influences the detection frequency of mutated genes. As more sensitive assays detect more mutated genes in clinical samples, this must be taken into consideration when determining KRAS gene status in clinical practice.
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2497
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Abstract
Rapid technical advances in DNA sequencing and genome-wide association studies are driving the discovery of the germline and somatic mutations that are present in different cancers. Mutations in genes involved in cellular signaling are common, and often shared by tumors that arise in distinct anatomical locations. Here we review the most important molecular changes in different cancers from the perspective of what should be analyzed on a routine basis in the clinic. The paradigms are EGFR mutations in adenocarcinoma of the lung that can be treated with gefitinib, KRAS mutations in colon cancer with respect to treatment with EGFR antibodies, and the use of gene-expression analysis for ER-positive, node-negative breast cancer patients with respect to chemotherapy options. Several other examples in both solid and hematological cancers are also provided. We focus on how disease subtypes can influence therapy and discuss the implications of the impending molecular diagnostic revolution from the point of view of the patients, clinicians, and the diagnostic and pharmaceutical companies. This paradigm shift is occurring first in cancer patient management and is likely to promote the application of these technologies to other diseases.
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Affiliation(s)
- Timothy J R Harris
- SAIC-Frederick, National Cancer Institute at Frederick, Frederick, MD 21702, USA.
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2498
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Tejpar S, Bertagnolli M, Bosman F, Lenz HJ, Garraway L, Waldman F, Warren R, Bild A, Collins-Brennan D, Hahn H, Harkin DP, Kennedy R, Ilyas M, Morreau H, Proutski V, Swanton C, Tomlinson I, Delorenzi M, Fiocca R, Van Cutsem E, Roth A. Prognostic and predictive biomarkers in resected colon cancer: current status and future perspectives for integrating genomics into biomarker discovery. Oncologist 2010; 15:390-404. [PMID: 20350999 PMCID: PMC3227961 DOI: 10.1634/theoncologist.2009-0233] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The number of agents that are potentially effective in the adjuvant treatment of locally advanced resectable colon cancer is increasing. Consequently, it is important to ascertain which subgroups of patients will benefit from a specific treatment. Despite more than two decades of research into the molecular genetics of colon cancer, there is a lack of prognostic and predictive molecular biomarkers with proven utility in this setting. A secondary objective of the Pan European Trials in Adjuvant Colon Cancer-3 trial, which compared irinotecan in combination with 5-fluorouracil and leucovorin in the postoperative treatment of stage III and stage II colon cancer patients, was to undertake a translational research study to assess a panel of putative prognostic and predictive markers in a large colon cancer patient cohort. The Cancer and Leukemia Group B 89803 trial, in a similar design, also investigated the use of prognostic and predictive biomarkers in this setting. In this article, the authors, who are coinvestigators from these trials and performed similar investigations of biomarker discovery in the adjuvant treatment of colon cancer, review the current status of biomarker research in this field, drawing on their experiences and considering future strategies for biomarker discovery in the postgenomic era.
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Affiliation(s)
- Sabine Tejpar
- Digestive Oncology Unit, University Hospital Gasthuisberg, Leuven, Belgium.
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2499
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Wilken JA, Webster KT, Maihle NJ. Trastuzumab Sensitizes Ovarian Cancer Cells to EGFR-targeted Therapeutics. J Ovarian Res 2010; 3:7. [PMID: 20346177 PMCID: PMC2861058 DOI: 10.1186/1757-2215-3-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Accepted: 03/27/2010] [Indexed: 12/18/2022] Open
Abstract
Background Early studies have demonstrated comparable levels of HER2/ErbB2 expression in both breast and ovarian cancer. Trastuzumab (Herceptin), a therapeutic monoclonal antibody directed against HER2, is FDA-approved for the treatment of both early and late stage breast cancer. However, clinical studies of trastuzumab in epithelial ovarian cancer (EOC) patients have not met the same level of success. Surprisingly, however, no reports have examined either the basis for primary trastuzumab resistance in ovarian cancer or potential ways of salvaging trastuzumab as a potential ovarian cancer therapeutic. Methods An in vitro model of primary trastuzumab-resistant ovarian cancer was created by long-term culture of HER2-positive ovarian carcinoma-derived cell lines with trastuzumab. Trastuzumab treated vs. untreated parental cells were compared for HER receptor expression, trastuzumab sensitivity, and sensitivity to other HER-targeted therapeutics. Results In contrast to widely held assumptions, here we show that ovarian cancer cells that are not growth inhibited by trastuzumab are still responsive to trastuzumab. Specifically, we show that responsiveness to alternative HER-targeted inhibitors, such as gefitinib and cetuximab, is dramatically potentiated by long-term trastuzumab treatment of ovarian cancer cells. HER2-positive ovarian carcinoma-derived cells are, therefore, not "unresponsive" to trastuzumab as previously assumed, even when they not growth inhibited by this drug. Conclusions Given the recent success of EGFR-targeted therapeutics for the treatment of other solid tumors, and the well-established safety profile of trastuzumab, results presented here provide a rationale for re-evaluation of trastuzumab as an experimental ovarian cancer therapeutic, either in concert with, or perhaps as a "primer" for EGFR-targeted therapeutics.
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Affiliation(s)
- Jason A Wilken
- Yale University, School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, PO Box 208063, 310 Cedar Street, New Haven, CT 06520-8063, USA.
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2500
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Smith G, Bounds R, Wolf H, Steele RJC, Carey FA, Wolf CR. Activating K-Ras mutations outwith 'hotspot' codons in sporadic colorectal tumours - implications for personalised cancer medicine. Br J Cancer 2010; 102:693-703. [PMID: 20147967 PMCID: PMC2837563 DOI: 10.1038/sj.bjc.6605534] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Background: Response to EGFR-targeted therapies in colorectal cancer patients has been convincingly associated with Kirsten-Ras (K-Ras) mutation status. Current mandatory mutation testing for patient selection is limited to the K-Ras ‘hotspot’ codons 12 and 13. Methods: Colorectal tumours (n=106) were screened for additional K-Ras mutations, phenotypes compared in transformation and Ras GTPase activating assays and gene and pathway changes induced by individual K-Ras mutants identified by microarray analysis. Taqman-based gene copy number and FISH analyses were used to investigate K-Ras gene amplification. Results: Four additional K-Ras mutations (Leu19Phe (1 out of 106 tumours), Lys117Asn (1 out of 106), Ala146Thr (7 out of 106) and Arg164Gln (1 out of 106)) were identified. Lys117Asn and Ala146Thr had phenotypes similar to the hotspot mutations, whereas Leu19Phe had an attenuated phenotype and the Arg164Gln mutation was phenotypically equivalent to wt K-Ras. We additionally identified a new K-Ras gene amplification event, present in approximately 2% of tumours. Conclusions: The identification of mutations outwith previously described hotspot codons increases the K-Ras mutation burden in colorectal tumours by one-third. Future mutation screening to facilitate optimal patient selection for treatment with EGFR-targeted therapies should therefore be extended to codon 146, and in addition should consider the unique molecular signatures associated with individual K-Ras mutations.
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Affiliation(s)
- G Smith
- Biomedical Research Institute, Ninewells Hospital and Medical School, Dundee, UK
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