Limoges, France
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Landoulsi A.,CNRS XLIM Research Institute, Limoges | Zhang L.Y.,CNRS XLIM Research Institute, Limoges | Dalmay C.,CNRS XLIM Research Institute, Limoges | Lacroix A.,University of Limoges | And 7 more authors.
IEEE MTT-S International Microwave Symposium Digest | Year: 2013

This paper presents an improved design of resonant biosensor, dedicated to dielectric analysis on biological cells at microwave frequencies. Such sensor uses the capability of microwaves to penetrate inside biological cells in order to interact with their intracellular content. Hence, individual dielectric properties of the cell cytoplasm can be known and then used as a signature of the cell pathological state (living or dead, malignant or safe...). In this paper is introduced a continuously tunable frequency sensor prototype, able to perform an accurate dielectric analysis over at least a 1GHz bandwidth while keeping enough sensitivity to detect and analyze a single cell. As a proof of concept, permittivity measurements have been led on calibrated size polystyrene beads: achieved results show good agreement with expected permittivity values. Finally experiments on Glioblastoma cells will be presented. © 2013 IEEE.


Zhang L.Y.,University of Limoges | Du Puch C.B.M.,Oncomedics | Lacroix A.,University of Limoges | Dalmay C.,University of Limoges | And 6 more authors.
IEEE MTT-S International Microwave Symposium Digest | Year: 2012

This paper illustrates the potential of microwave frequencies for biological analysis. Once penetrating inside biological cells, microwaves can interact with their intracellular content and inform on their safe or malignant state. This work demonstrates that their cancer grade (i.e. aggressiveness level) can also be identified by this way. Hence, based on permittivity measurements on three colon cancer cell lines loading RF resonators, the presented results show significant differences of electromagnetic signature in the cancer grade of analyzed cells. This sensing method appears very promising to develop new powerful tools for early cancer diagnostic. © 2012 IEEE.


Giraud S.,Oncomedics | Bounaix Morand Du Puch C.,Oncomedics | Fermeaux V.,University of Limoges | Guillaudeau A.,University of Limoges | Lautrette C.,Oncomedics
Anticancer Research | Year: 2012

Background: Among targeted therapies, Herceptin is a monoclonal antibody successfully used on patients with breast cancer expressing Human Epidermal Growth Factor Receptor-2 (HER2 receptors). Oncogramme is a method developed to predict anticancer activity of molecules and thus individualize chemotherapeutic strategies. Before this ex vivo test enters clinical validation, it was desirable to correlate breast cancer cell responses to Herceptin observed through Oncogramme with HER2 expression by these cells. Materials and Methods: Breast tumour fragments were dissociated and obtained cells were cultured in defined medium. After Herceptin treatment, cytotoxicity was detected by cell death analysis, and responses compared to tumour HER2 status were determined by pathologists. Results: Cell responses to increasing doses of Herceptin obtained with Oncogramme were in correlation with HER2 expression. Conclusion: Comparison between Herceptin responses obtained with Oncogramme and HER2 status of breast tumour cells confirmed that Oncogramme is a reliable method for prediction of patient cell sensitivity to anticancer drugs.


Zhang L.Y.,CNRS XLIM Research Institute, Limoges | Bounaix Morand Du Puch C.,Oncomedics | Dalmay C.,CNRS XLIM Research Institute, Limoges | Lacroix A.,University of Limoges | And 11 more authors.
Sensors and Actuators, A: Physical | Year: 2014

This paper illustrates the potential of microwave frequencies for biological analysis and cell discrimination. Microwave electric fields have the capability to penetrate inside cells and interact with their intracellular content. Hence, measuring cell electrical properties in the Gigahertz frequency spectrum may allow distinguishing intracellular differences between cells without requiring any labeling or denaturation. Here, we present how microwave resonators can be used as biosensors to measure individual cell dielectric permittivity and obtain characteristic electromagnetic signatures as a function of the cell type considered, in particular their cancer cell stage (i.e. aggressiveness level). Five cell lines, all derived from low to high grade human colorectal tumors, were cultured on-chip or simply deposited in water droplets on microwave biosensors. For this preliminary study, the sensors only operated in air for frequencies ranging from 5 GHz to 14 GHz, allowing establishing a representative electromagnetic signature. During our experiments, sensors were fully dried, and a fixation step allowed the reproducible characterization of cells outside their culture medium, in ambient air, while maintaining their intracellular content unmodified. Results showed significant electromagnetic signature differences between cell lines, especially between cells with low and high aggressiveness levels. We also show that a correlation might be envisioned between the measured electromagnetic signatures and the potential aggressiveness stage. At this level, we stand at the proof-of-concept stage, and a clinical investigation will be required to establish from several patients both the reliability and the reproducibility of the potentially existing relationship between electromagnetic signatures identified in this study and actual cancer progression. © 2014 Elsevier B.V.


Patent
University of Limoges and Oncomedics | Date: 2014-12-24

Method for determining, in vitro, the cell aggressiveness grade of cancer cells or for detecting cancer stem cells in a cell sample originating from a solid tissue suspected of being cancerous, includes: a) dissociating the cell cluster constituting the sample into a suspension of whole and viable isolated cells, b) macroscopically sorting the cells to obtain homogeneous subpopulations, c) calibrating at least one microwave electromagnetic sensor resonating at its own resonance frequency, d) presenting the dissociated and sorted cells to the calibrated sensor, e) interrogating the sensor and determining its new resonance frequency having received the cells, f) calculating the variation in overall dielectric permittivity of the cells according to the variation in working frequency, which constitutes the electromagnetic signature of the cells. The macroscopic sorting is without prior labelling and is based on the intrinsic properties of the cells. A kit for implementing the method is also described.


Melin C.,University of Limoges | Perraud A.,University of Limoges | Perraud A.,Limoges University Hospital Center | Bounaix Morand du Puch C.,Oncomedics | And 8 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2014

The development of methods to enrich cell populations for cancer stem cells (CSC) is urgently needed to help understand tumor progression, therapeutic escape and to evaluate new drugs, in particular for colorectal cancer (CRC). In this work, we describe the in vitro use of OncoMiD for colon, a CRC-specific primary cell culture medium, to enrich CRC cell lines in CSC. Sedimentation field flow fractionation (SdFFF) was used to monitor the evolution of subpopulations composition. In these models, medium induced a loss of adherence properties associated with a balance between proliferation and apoptosis rates and, more important, an increased expression of relevant CSC markers, leading to specific SdFFF elution profile changes. © 2014 Elsevier B.V.


PubMed | University of Limoges, Oncomedics and Limoges University Hospital Center
Type: | Journal: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences | Year: 2014

The development of methods to enrich cell populations for cancer stem cells (CSC) is urgently needed to help understand tumor progression, therapeutic escape and to evaluate new drugs, in particular for colorectal cancer (CRC). In this work, we describe the in vitro use of OncoMiD for colon, a CRC-specific primary cell culture medium, to enrich CRC cell lines in CSC. Sedimentation field flow fractionation (SdFFF) was used to monitor the evolution of subpopulations composition. In these models, medium induced a loss of adherence properties associated with a balance between proliferation and apoptosis rates and, more important, an increased expression of relevant CSC markers, leading to specific SdFFF elution profile changes.


Giraud S.,Oncomedics | Loum E.,Oncomedics | Bessette B.,Oncomedics | Fermeaux V.,Service dAnatomopathologie | Lautrette C.,Oncomedics
Anticancer Research | Year: 2011

Background: Breast cancer is the most widely spread cancer in the world, attracting much research and individualized tumour response testing (ITRT) methods are now used to individualize patient chemotherapeutic administrations. A new ITRT method was developed with optimized processing. Materials and Methods: Breast tumour fragments were separated and the cells seeded in a foetal calf serum-free defined medium. After various chemotherapeutic treatments, cytotoxicity was determined by cell death detection with calcein acetoxymethyl and ethidium homodimer labelling. Results: The culture medium allowed breast tumour cell proliferation in culture, while preventing fibroblastic cell survival. Moreover, the cell death analysis gave rise to a chemoresistance profile called an Oncogramme, with statistically significant values. Conclusion: The Oncogramme is a new ITRT method which can predict patient cell sensitivities to chemotherapeutics and should be validated by a new phase I clinical trial.

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