Label-free DNA-methylation detection by direct ds-DNA fragment screening using poly-purine hairpins
Huertas, César S. (Institut Català de Nanociència i Nanotecnologia)
Aviñó, Ana (Institut de Química Avançada de Catalunya)
Kurachi, Cristina (Institut Català de Nanociència i Nanotecnologia)
Piqué, Albert (Institut Català de Nanociència i Nanotecnologia)
Sandoval, Juan (Institut d'Investigació Biomèdica de Bellvitge)
Eritja, Ramon (Institut de Química Avançada de Catalunya)
Esteller, M. (Institució Catalana de Recerca i Estudis Avançats)
Lechuga, Laura M (Institut Català de Nanociència i Nanotecnologia)

Date:	2018
Abstract:	Cancer diagnosis continuously evolves due to the better understanding of tumorigenic processes. DNA-methylation is consolidated as an effective biomarker for cancer prognosis and diagnostic even in tumors of unknown origin. The reversibility of this epigenetic mechanism also places it as a high-profile tool for the development of more sophisticated and personalized therapies. Current methodologies, such as bisulfite conversion or PCR amplification, rely on complex procedures that make difficult the standardization of epigenetics analyses. Here we present an optical biosensor methodology based on Surface Plasmon Resonance that employs poly-purine reverse-Hoogsten hairpin probes capable of interacting directly with ds-DNA fragments by triple helix formation. The direct interaction with the material of interest can greatly enhance the reliability of the analysis providing a more accurate and precise diagnosis. We have demonstrated the capabilities of our methodology for the direct capture of ds-DNA fragments and specific methyl-cytosine quantification. Our poly-purine hairpin probe demonstrated the specific capture of ds-DNA fragments while the standard duplex-forming probes failed to do so. In addition, the biosensor methodology showed a strong correlation with the different DNA methylation status between the sequences with a low signal variation (≤ 8%CV) along 35 hybridization/regeneration cycles. Through its straightforward procedure and versatility of detecting different DNA modifications related to the DNA methylation process, we anticipate that our strategy will enable a greater level of accuracy and precision in cancer diagnostics making a strong impact on the development of personalized therapies.
Grants:	Ministerio de Economía y Competitividad CTQ2010-20541 Ministerio de Economía y Competitividad CTQ2014-52588-R Agència de Gestió d'Ajuts Universitaris i de Recerca 2009/SGR-208 Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-624 Ministerio de Economía y Competitividad SEV-2013-0295
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	DNA methylation ; DNA capture ; Surface plasmon resonance ; Biosensor ; Diagnosis ; Triplex
Published in:	Biosensors & bioelectronics, Vol. 120 (November 2018) , p. 47-54, ISSN 1873-4235

DOI: 10.1016/j.bios.2018.08.027

Postprint 28 p, 1.0 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles