Brief Article
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World J Gastroenterol. Aug 28, 2012; 18(32): 4419-4426
Published online Aug 28, 2012. doi: 10.3748/wjg.v18.i32.4419
Development of a quantum-dot-labelled magnetic immunoassay method for circulating colorectal cancer cell detection
Maria Gazouli, Anna Lyberopoulou, Pericles Pericleous, Spyros Rizos, Gerassimos Aravantinos, Nikolaos Nikiteas, Nicholas P Anagnou, Efstathios P Efstathopoulos
Maria Gazouli, Anna Lyberopoulou, Nicholas P Anagnou, Department of Basic Medical Sciences, Laboratory of Biology, School of Medicine, University of Athens, 11527 Athens, Greece
Pericles Pericleous, Spyros Rizos, First Department of Surgery, “Tzaneion” General Hospital, 18536 Piraeus, Greece
Gerassimos Aravantinos, Third Department of Internal Medicine, Agii Anargyri Hospital, 14564 Athens, Greece
Nikolaos Nikiteas, Second Department of Propedeutic Surgery, University of Athens School of Medicine, Laiko General Hospital, 11527 Athens, Greece
Efstathios P Efstathopoulos, Department of Radiology, Attikon University Hospital, 12462 Athens, Greece
Author contributions: All the authors contributed equally to the work.
Supported by The John S Latsis Public Benefit Foundation; The Hellenic Society of Medical Oncology
Correspondence to: Maria Gazouli, PhD, Assistant Professor of Molecular Biology, Department of Basic Medical Sciences, Laboratory of Biology, School of Medicine, University of Athens, Michalakopoulou 176, 11527 Athens, Greece. mgazouli@med.uoa.gr
Telephone: +30-210-7462231 Fax: +30-210-7462231
Received: June 15, 2012
Revised: August 14, 2012
Accepted: August 18, 2012
Published online: August 28, 2012
Abstract

AIM: To detect of colorectal cancer (CRC) circulating tumour cells (CTCs) surface antigens, we present an assay incorporating cadmium selenide quantum dots (QDs) in these paper.

METHODS: The principle of the assay is the immunomagnetic separation of CTCs from body fluids in conjunction with QDs, using specific antibody biomarkers: epithelial cell adhesion molecule antibody, and monoclonal cytokeratin 19 antibody. The detection signal was acquired from the fluorescence signal of QDs. For the evaluation of the performance, the method under study was used to isolate the human colon adenocarcinoma cell line (DLD-1) and CTCs from CRC patients’ peripheral blood.

RESULTS: The minimum detection limit of the assay was defined to 10 DLD-1 CRC cells/mL as fluorescence was measured with a spectrofluorometer. Fluorescence-activated cell sorting analysis and Real Time RT-PCR, they both have also been used to evaluate the performance of the described method. In conclusion, we developed a simple, sensitive, efficient and of lower cost (than the existing ones) method for the detection of CRC CTCs in human samples. We have accomplished these results by using magnetic bead isolation and subsequent QD fluorescence detection.

CONCLUSION: The method described here can be easily adjusted for any other protein target of either the CTC or the host.

Keywords: Circulating tumor cells; Cancer; Quantum dots; Nanoprobes; Micrometastasis