Representative Publications
J1. Fabrication, Characterization, and Evaluation in Drug Release Properties of Magnetoactive Poly(ethylene oxide)-Poly(l-lactide) Electrospun Membranes. Savva I, Odysseos AD. Evaggelou L, Marinica O, Vasile E, Vekas L, Sarigiannis Y, Krasia –Christoforou T. Biomacromolecules 2013.Dec9:14(12):4436-46
The fabrication of electrospun magnetoactive fibrous nanocomposite membranes based on the water-soluble and biocompatible poly(ethylene oxide) (PEO), the biocompatible and biodegradable poly(L-lactide) (PLLA) and preformed oleic acid-coated magnetite nanoparticles (OA.Fe3O4) is reported. Visualization of the membranes by electron microscopy techniques reveals the presence of continuous fibers of approximately 2 μm in diameter, with the magnetic nanoparticles being evenly distributed within the fibers, retaining at the same time their nanosized diameters (≈ 5 nm). Thermal gravimetric analysis measurements suggest that the magnetic nanoparticles embedded within the polymer fibers affect favorably the thermal stability of the membranes. Moreover, assessment of their magnetic characteristics by vibrating sample magnetometry discloses tunable superparamagnetic behavior at ambient temperature. For the first time, the biocompatibility and biodegradability of PEO/PLLA and the tunable magnetic activity of the OA.Fe3O4 are combined in the same drug delivery system, with N-acetyl-p-aminophenol (acetaminophen) as a proof-of-concept pharmaceutical. Furthermore, their heating ability under alternating current (AC) magnetic field conditions is evaluated using frequency of 110 kHz and corresponding magnetic field strength of 25 mT (19.9 kA/m). Consequently, these magnetoactive fibrous nanocomposites exhibit promising characteristics for future exploitation in magnetothermally triggered drug delivery.
J2. The role of constitutive behaviour interaction with the host tissue on the state of stress and growth of solid tumors. Voutouris C, Mpekris F, Michael S, Papageorgis P, Odysseos AD, Stylianopoulos T. PlosOne2014. Aug11: 9(8):1-9.
Mechanical forces play a crucial role in tumor patho-physiology. Compression of cancer cells inhibits their proliferation rate, induces apoptosis and enhances their invasive and metastatic potential. Additionally, compression of intratumor blood vessels reduces the supply of oxygen, nutrients and drugs, affecting tumor progression and treatment. Despite the great importance of the mechanical microenvironment to the pathology of cancer, there are limited studies for the constitutive modeling and the mechanical properties of tumors and on how these parameters affect tumor growth. Also, the contribution of the host tissue to the growth and state of stress of the tumor remains unclear. To this end, we performed unconfined compression experiments in two tumor types and found that the experimental stress-strain response is better fitted to an exponential constitutive equation compared to the widely used neo-Hookean and Blatz-Ko models. Subsequently, we incorporated the constitutive equations along with the corresponding values of the mechanical properties - calculated by the fit - to a biomechanical model of tumor growth. Interestingly, we found that the evolution of stress and the growth rate of the tumor are independent from the selection of the constitutive equation, but depend strongly on the mechanical interactions with the surrounding host tissue. Particularly, model predictions - in agreement with experimental studies - suggest that the stiffness of solid tumors should exceed a critical value compared with that of the surrounding tissue in order to be able to displace the tissue and grow in size. With the use of the model, we estimated this critical value to be on the order of 1.5. Our results suggest that the direct effect of solid stress on tumor growth involves not only the inhibitory effect of stress on cancer cell proliferation and the induction of apoptosis, but also the resistance of the surrounding tissue to tumor expansion.
J3. Stylianopoulos T, Kokonou M, Michael S, Tryfonos A, Rebholz C, Odysseos AD, Doumanidis C. Tensile mechanical properties and hydraulic permeabilities of electrospun cellulose acetate fiber meshes. J Biomed Mater Res B Appl Biomater. 2012 Nov;100(8):2222-30. doi: 10.1002/jbm.b.32791. Epub 2012 Aug 9.
The mechanical properties and hydraulic permeabilities of biomaterial scaffolds play a crucial role in their efficacy as tissue engineering platforms, separation processors, and drug delivery vehicles. In this study, electrospun cellulose acetate fiber meshes of random orientations were created using four different concentrations, 10.0, 12.5, 15.0, and 17.5 wt % in acetone or ethyl acetate. The tensile mechanical properties and the hydraulic permeabilities of these meshes were measured, and a multiscale model was employed to predict their mechanical behavior. Experimentally, the elastic modulus ranged from 3.5 to 12.4 MPa depending on the polymer concentration and the solvent. Model predictions agreed well with the experimental measurements when a fitted single-fiber modulus of 123.3 MPa was used. The model also predicted that changes in fiber alignment may result in a 3.6-fold increase in the elastic modulus for moderately aligned meshes and a 8.5-fold increase for highly align meshes. Hydraulic permeabilities ranged from 1.4 x 10(-12) to 8.9 x 10(-12) m(2) depending on polymer concentration but not the choice of solvent. In conclusion, polymer concentration, fiber alignment, and solvent have significant impact on the mechanical and fluid transport properties of electrospun cellulose acetate fiber meshes
J4. Khodr Issa, Panayiota Stylianou, Ana-Belen D’Avilla-Ibanez, Sofia Iliopouloa, Jean-Michel Siaugue, Andreas, Andreas Evdokiou, Triantafyllos Stylianopoulos, Costas Pitris and Andreani D. Odysseosa Spatiotemporal Distribution of Silica-Coated, Dye-Doped Machemite Nanoparticles in Normal Brain Tissue and Orthotopic Glioblastoma Models (Under publication. Nanomedicine)
Therapeutic responses of Glioblastoma Multiforme to small molecule targeted therapies remain insufficient mainly due to inadequate uptake by the invasive tumor peripheral zone. We introduce end-functionalized, pegylated silica-coated, bimodal nanoparticles capable to preferentially accumulate in these regions. Spatial or temporal distribution of either nanoparticle systems across diverse regions of orthotopic glioblastoma tumors and their correlation with blood vessel characteristics, has been quantified by the nanoparticle fluorescence intensity per tissue area, which is analogous to nanoparticle concentration, both outside the tumor and inside as a function of distance from the tumor rim, applying image processing algorithms. Anionic and smaller size nanoparticles have followed a more favorable distribution pattern within the highly vascularized tumor boundaries. Their correlation with tumor vessel characteristics has been verified by numerical modelling. These findings introduce a promising solution for delivery of therapeutics within the invasive tumor zone, prevent glioblastoma recurrence and reduce morbidity.
J5. Patent: EP 1517412121403 and USPO 9,890,187: Prototype systems of theranostic biomarkers for in vivo molecular management of cancer (Odysseos AD, Pitris C, Keramidas A).
Representative Projects
P1. Management of Resistance to Tyrosine Kinase Inhibitors with Advanced Nanosystems. FP7-PEOPLE-IAPP: NANORESISTANCE 286125: Nov 2011-October 2015. € 1,400.000. Principal Investigator: A. Odysseos.
NANORESISTANCE introduces for the first time (i) receptor -independent targeting of Epidermal Growth Factor Receptor-kinase activity, (ii) nuclear delivery of anti-Epidermal Growth Factor Receptor therapy with novel grafting techniques and (iii) the deciphering of resistance and lack of responsiveness to anti-EGFR therapies in the preclinical setting with mathematical models of interstitial biodistribution. This work defines an unprecedented integrated approach for the comprehensive management of failure to anti-EGFR therapy and treatment monitoring. This partnership will play a structuring role by allowing researchers to acquire key skills equally relevant to the public and private sectors including cutting edge nanobiotechnology techniques for fabrication of nanotheranostic conjugates for targeted nuclear drug delivery and imaging, pioneering approaches for intracellular targeting with carbon nanotubes (CNT), innovative mathematical models and assessment of biodistribution, state-of-the-art Surface Plasmon Resonance for assessing drug-target interactions, emerging technologies for in vivo protein-protein and theranostic compound-protein interaction with Bimolecular Fluorescence Complementation Assays (BIFCs).These parallel approaches provide a promising innovative solution in the multifaceted challenge of the overall resistance to anti-EGFR therapies. This will be achieved with the development of multimodal CNT-based nanoplatforms carrying the fluorescent conjugates of EGFR inhibitors intracellularly independently of EGFR extracellular recognition. This system will further deliver anti-EGFR and fluorescent attributes to the nucleus. The partnership offers and a well-structured scheme of complementary skills highly inspired by the entrepreneurial spirit of academicians and research commitment of the industrial partners securing significant impact on their employability in their sector.
P2. Mechanistic Approaches in Cellular and Biological Barriers- Sub-project: The Blood-Brain Tumour Barrier FP7-PEOPLE-ITN: PATHCHOOSER: October 2013-September 2017, € 3,178.803 (Lead of Training, A. Odysseos)
Nanomedicine offers capability to significantly change the course of treatment for lifethreatening diseases. Many of the most significant current therapeutic targets, to be viable in practice, require the efficient crossing of at least one biological barrier. However, the efficient and controlled crossing of the undamaged barrier is difficult. The range of small molecules that can successfully do so (via diffusive or other non-specific processes) is limited in size and physiochemical properties, greatly restricting the therapeutic strategies that may be applied. In practice, after several decades of limited success, there is a broad consensus that new multidisciplinary, multi-sectoral strategies are required. Key needs include detailed design and understanding of the bionano-interafce, re-assessment of in vitro models used to assess transport across barriers, and building regulatory considerations into the design phase of nanocarriers. The overarching premises of the PathChooser ITN are that (i) significant advances can only be made by a more detailed mechanistic understanding of key fundamental endocytotic, transcytotic, and other cellular processes, especially biological barrier crossing; (ii) elucidating the Mode of Action / mechanism of successful delivery systems (beyond current level) will ensure more rapid regulatory and general acceptance of such medicines. Paramount in this is the design and characterization of the in situ interface between the carrier system and the uptake and signalling machinery. (iii) inter-disciplinary knowledge from a range of scientific disciplines is required to launch a genuine attack on the therapeutic challenge. The PathChooser ITN program of research and training will equip the next generation of translational scientists with the tools to develop therapies for a range of currently intractable (e.g. hidden in the brain) and economically unviable diseases (e.g. orphan diseases affecting a limited population).
P3. Multipotent Theranostic Metal-Based Scaffolds for Molecular Targeting of Colorectal Cancer (Cyprus Research Promotion Foundation; 2012-2015) June. 2012- May. 2014. € 178.803. Project Coordinator: C. Pitris ; Partner: A. Odysseos
This project brings together expertise in medical optics and optoelectronics, magnetics, coordinate Lanthanide chemistry, bio-organic synthesis and molecular oncology, aiming at introducing a break-through solution for the overall management of colorectal cancer and potentially other malignancies expressing the epidermal growth factor family of receptors (EGFR). The solutions is based on prototype metal-based functionalized compounds engaging cutting-edge synthetic and complexation approaches. Initially, a panel of kinetically stable prototype lanthanides complexes with potent (a) optical (e.g near infrared spectroscopic) and (b) magnetic /relaxation properties will be designed and synthesized as building blocks for heterometallic arrays and subsequently the lanthanide complexes will be functionalized to a series of biologically active bimodal theranostic agents with anti-EGFR recognizing and inhibiting properties. Functionalization of the probes with the recognizing and therapeutic ligands (i.e. anilinoquinazolines) will increase the molecular size, thus optimizing proton relaxivity and magnetic efficacy. Diagnostic specificity will be assessed by ERB-B1 recognition and internalization of the compounds on (a) cell monolayers and (b) 3-dimensional tissue phantoms of cell lines differentially expressing ERB-B1 under inverted NIR microscope. Highly sensitive and efficacious compounds will be considered for further development as theranostic agents for early detection and therapy of CRC in subsequent pre-clinical models with the application of multimodal Molecular Imaging. This approach enables the quantitative imaging of defined cancer biomarkers in a non-invasive manner, aiding in lesion detection, patient stratification, new drug development and validation, dose optimization and treatment monitoring.
P4. Nanofiber Electrospinning and Rapid Prototyping for Intestinal Tissue Engineering (Cyprus Research Promotion Foundation; 2009-2011). €137.688 Partner and Deputy Coordinator, A. Odysseos
Adaptation of Nanofiber Electrospinning for Rapid Prototyping: A mesoscale-resolution electrospinning RP system based on a 3-axis CNC machine was set up and configured. A collector for layered deposition based on spraying of graphite microparticles in sacrificial intermediate layers was tested, as well as a polystyrene foil mask on the target to patern electrospun areas The innovative idea of structuring of the electrospun fiber membrane surface to conform to the epithelial geometry of intestinal tissue by patterned electrochemical roughening of the metal foil target, onto which the fibers are deposited during electrospinning, was introduced. For software integration, an electrospinning process-structure database was assembled by parametric studies for cellulose acetate , and is to be combined with imaging software (STL format) for tissue geometry encoding .
Tissue model design 1 was based on surgical collection of 37 tissue specimens at the Nicosia General Hospital, with tissues already imaged by optical microscopy, SEM and 3D laser scanning, white-light profilometry and X-ray microtomography, with SEM proving the most appropriate technique. Fabrication of tissue scaffolds was performed at the HO with SEM parametric studies for electrospinning of fiber membranes made of CA (also with PANI), PEO, PLLA and PEO/PLLA mixtures. Functional analysis was realized with dynamic mechanical analysis (DMA) and rheological analysis of a great variety of CA nanofiber membranes. SEM analysis was performed on the cell-cultured scaffolds for subsequent intestinal tissue processing and engineering. Tissue phantom have been developed with intestinal cells incorporated in a collagen mixture. The partners introduced the family of vitamin E derivatives (tocopherols-tocotrienols) as a new super-family of growth and differentiation factors in the normal intestinal cell.
P5. Chemical Approaches to Targeting Drug Resistance in Cancer Stem Cells. COST CM1106 (2012-2016).
This COST Action aims to unite researchers with expertise in rational drug design and the medicinal chemistry of synthetic and natural compounds with biomedical investigators dedicated to the understanding the mechanisms governing drug resistance in cancer stem cells. Cancer stem cells (CSC) are a subpopulation of cells within tumors that exhibit enhanced tumor-initiating attributes and are a major contributing factor to current cancer therapy failure. The CSC phenotypic state comprises distinct molecular and functional differences that underpin resistance to current treatments and the unique ability spread and to seed new tumors throughout the body. This insight necessitates an entirely new approach to cancer drug development to effectively target tumor CSCs. Through exchange of information, experience and expertise, researcher mobility and fostering new collaboration between chemistry and biology groups, the Action endeavours to develop new, effective methods for identifying novel compounds and drug candidates that target drug-resistant cancer stem cells.