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Volume 9, Issue 9 (Suppl) J Cancer Sci Ther, an open access journal
ISSN: 1948-5956 World Cancer 2017
October 19-21, 2017
25th WORLD CANCER CONFERENCE
October 19-21, 2017 | Rome, Italy
3D imaging detection method of HER2: Application of dual conjugated affibody-quantum dots
probes and ratiometric analysis
Perla Pérez-Treviño1, Héctor Hernández-Cerda1, Oscar Fajardo1, Noemí García1, 2 and Julio Altamirano1, 2
1Tecnologico de Monterrey(ITESM), , Mexico
2Hospital Zambrano-Hellion, Mexico
HER2 overexpression is associated with Breast Cancer (BC) poor prognosis, due to increased metastases and angiogenesis,
and decreased apoptosis. HER2 is commonly assessed by immunohistochemistry. Technique that requires extensive
sample processing to get thin fixed samples (3-5 m) that are analyzed using standard HER2 detection probes, and subjective
algorithms forHER2 interpretation. Consequently, lacks accuracy and reproducibility, and could lead tomisdiagnosis.Therefore,
we developed a 3D imaging detection method of HER2 using affibody molecules conjugated with quantum dots (Aff-QDs)
and ratiometric analysis (RMA). Affibody anti-HER2 and affibody negative control were conjugated by the maleimide reaction
with QD605 and QD545, respectively. Fixed HER2+ and HER2-BC spheroids were incubated with a mixture (1:1) of both Aff-
QDs, and confocal image stacks were recorded in the z-axis. Images were processed by RMA (AffantiHER2-QD605/Affneg-
QD545 fluorescence), to assess the specific HER2 signal. We found that the non-specific accumulation for both Aff-QDs was
the same within HER2-spheroids. However, the AffantiHER2-QD605 signal in HER2+ spheroids, was significantly higher
(5.910.81 F/F0) than that of Affneg-QD545 (2.670.56 F/F0, p<0.05) and was optimally resolved up to 50 m depth. After
RMA, non-specific signals were removed in HER2+ and HER2- spheroids, and no false HER2 signal was found. Therefore,
Aff-QDs can efficiently penetrate in spheroids, used as 3D BC models, with minimal sample manipulation; after RMA, specific
and objective 3D HER2 result can be obtained. The method proposed here, could reduce the typical problems associated with
traditional immunohistochemistry and improves HER2 detection by 3D analysis.
Biography
Perla Pérez-Treviño is a PhD student in Biotechnology from the Tecnologico de Monterrey (ITESM), Mexico. Since 2012 to the present, she has been working as
Research Assistant at Institute of Cardiology and Vascular Medicine, Zambrano-Hellion Hospital, School of Medicine, ITESM. She has published two papers as first
author in important peer reviewed journals and two more that are in revision. Her work is focused in the study of molecular and microstructural cell alterations during
various chronic pathologies, and currently, she is working in assessing the expression of biomarkers in 3D models of cancer cells growth and tumors.
Perla Pérez-Treviño et al., J Cancer Sci Ther 2017, 9:9(Suppl)
DOI: 10.4172/1948-5956-C1-111