201
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Molla MS, Katti DR, Katti KS. Mechanobiological evaluation of prostate cancer metastasis to bone using an in vitro prostate cancer testbed. J Biomech 2021; 114:110142. [PMID: 33290947 PMCID: PMC8281967 DOI: 10.1016/j.jbiomech.2020.110142] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 11/02/2020] [Accepted: 11/12/2020] [Indexed: 12/26/2022]
Abstract
Prostate cancer exhibits a propensity to metastasize to the bone, which often leads to fatality. Bone metastasis is characterized by complex biochemical, morphological, pathophysiological, and genetic changes to cancer cells as they colonize at bone sites. In this study, we report the evaluation of MDA PCa2b prostate cancer cells' nanomechanical properties during the mesenchymal-to-epithelial transition (MET) and during disease progression at the metastatic site. Bone-mimetic tissue-engineered 3D nanoclay scaffolds have been used to create in vitro metastatic site for prostate cancer. A significant softening of the prostate cancer cells during MET and further softening as disease progression occurs at metastasis is also reported. The significant reduction in elastic modulus of prostate cancer cells during MET was attributed to actin reorganization and depolymerization. This study provides input towards direct nanomechanical measurements to evaluate the time evolution of cells' mechanical behavior in tumors at bone metastasis site.
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Affiliation(s)
- Md Shahjahan Molla
- Center for Engineered Cancer Testbeds, Department of Civil and Environmental Engineering, NDSU, Fargo, ND 58104, United States; Biomedical Engineering, NDSU, Fargo, ND 58104, United States; Materials and Nanotechnology, NDSU, Fargo, ND 58104, United States.
| | - Dinesh R Katti
- Center for Engineered Cancer Testbeds, Department of Civil and Environmental Engineering, NDSU, Fargo, ND 58104, United States; Biomedical Engineering, NDSU, Fargo, ND 58104, United States; Materials and Nanotechnology, NDSU, Fargo, ND 58104, United States.
| | - Kalpana S Katti
- Center for Engineered Cancer Testbeds, Department of Civil and Environmental Engineering, NDSU, Fargo, ND 58104, United States; Biomedical Engineering, NDSU, Fargo, ND 58104, United States; Materials and Nanotechnology, NDSU, Fargo, ND 58104, United States.
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202
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Boot RC, Koenderink GH, Boukany PE. Spheroid mechanics and implications for cell invasion. ADVANCES IN PHYSICS: X 2021. [DOI: 10.1080/23746149.2021.1978316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Ruben C. Boot
- Department of Chemical Engineering, Delft University of Technology, Delft, The Netherlands
| | - Gijsje H. Koenderink
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Delft, The Netherlands
| | - Pouyan E. Boukany
- Department of Chemical Engineering, Delft University of Technology, Delft, The Netherlands
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203
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Affiliation(s)
- Chandra Has
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
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204
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Dannhauser D, Maremonti MI, Panzetta V, Rossi D, Netti PA, Causa F. Mechanical phenotyping of breast cell lines by in-flow deformation-dependent dynamics under tuneable compressive forces. LAB ON A CHIP 2020; 20:4611-4622. [PMID: 33146642 DOI: 10.1039/d0lc00911c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Cell mechanical properties are powerful biomarkers for label-free phenotyping. To date, microfluidic approaches assay mechanical properties by measuring changes in cellular shape, applying extensional or shear flows or forcing cells to pass through constrictions. In general, such approaches use high-speed imaging or transit time measurements to evaluate cell deformation, while cell dynamics in-flow after stress imposition have not yet been considered. Here, we present a microfluidic approach to apply, over a wide range, tuneable compressive forces on suspended cells, which result in well distinct signatures of deformation-dependent dynamic motions. By properly conceiving microfluidic chip geometry and rheological fluid properties, we modulate applied single-cell forces, which result in different motion regimes (rolling, tumbling or tank-treating) depending on the investigated cell line. We decided to prove our approach by testing breast cell lines, with well-known mechanical properties. We measured a set of in-flow parameters (orientation angle, aspect ratio, cell deformation and cell diameter) as a backward analysis of cell mechanical response. By such an approach, we report that the highly invasive tumour cells (MDA-MB-231) are much more deformable (6-times higher) than healthy (MCF-10A) and low invasive ones (MCF-7). Thus, we demonstrate that a microfluidic design with tuneable rheological fluid properties and direct analysis of bright-field images can be suitable for the label-free mechanical phenotyping of various cell lines.
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Affiliation(s)
- David Dannhauser
- Interdisciplinary Research Centre on Biomaterials (CRIB), Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli "Federico II", Piazzale Tecchio 80, 80125 Naples, Italy.
| | - Maria Isabella Maremonti
- Interdisciplinary Research Centre on Biomaterials (CRIB), Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli "Federico II", Piazzale Tecchio 80, 80125 Naples, Italy.
| | - Valeria Panzetta
- Interdisciplinary Research Centre on Biomaterials (CRIB), Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli "Federico II", Piazzale Tecchio 80, 80125 Naples, Italy.
| | - Domenico Rossi
- Center for Advanced Biomaterials for Healthcare@CRIB, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125 Naples, Italy
| | - Paolo Antonio Netti
- Interdisciplinary Research Centre on Biomaterials (CRIB), Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli "Federico II", Piazzale Tecchio 80, 80125 Naples, Italy. and Center for Advanced Biomaterials for Healthcare@CRIB, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125 Naples, Italy
| | - Filippo Causa
- Interdisciplinary Research Centre on Biomaterials (CRIB), Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli "Federico II", Piazzale Tecchio 80, 80125 Naples, Italy.
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205
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In-Situ Investigation on Nanoscopic Biomechanics of Streptococcus mutans at Low pH Citric Acid Environments Using an AFM Fluid Cell. Int J Mol Sci 2020; 21:ijms21249481. [PMID: 33322170 PMCID: PMC7764216 DOI: 10.3390/ijms21249481] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 12/28/2022] Open
Abstract
Streptococcus mutans (S. mutans) is widely regarded as the main cause of human dental caries via three main virulence factors: adhesion, acidogenicity, and aciduricity. Citric acid is one of the antibiotic agents that can inhibit the virulence capabilities of S. mutans. A full understanding of the acidic resistance mechanisms (ARMs) causing bacteria to thrive in citrate transport is still elusive. We propose atomic force microscopy (AFM) equipped with a fluid cell to study the S. mutans ARMs via surface nanomechanical properties at citric acid pH 3.3, 2.3, and 1.8. Among these treatments, at pH 1.8, the effect of the citric acid shock in cells is demonstrated through a significantly low number of high adhesion zones, and a noticeable reduction in adhesion forces. Consequently, this study paves the way to understand that S. mutans ARMs are associated with the variation of the number of adhesion zones on the cell surface, which is influenced by citrate and proton transport. The results are expected to be useful in developing antibiotics or drugs involving citric acid for dental plaque treatment.
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206
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Hao Y, Cheng S, Tanaka Y, Hosokawa Y, Yalikun Y, Li M. Mechanical properties of single cells: Measurement methods and applications. Biotechnol Adv 2020; 45:107648. [DOI: 10.1016/j.biotechadv.2020.107648] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/11/2020] [Accepted: 10/12/2020] [Indexed: 12/22/2022]
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207
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Gensbittel V, Kräter M, Harlepp S, Busnelli I, Guck J, Goetz JG. Mechanical Adaptability of Tumor Cells in Metastasis. Dev Cell 2020; 56:164-179. [PMID: 33238151 DOI: 10.1016/j.devcel.2020.10.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/18/2020] [Accepted: 10/16/2020] [Indexed: 12/12/2022]
Abstract
The most dangerous aspect of cancer lies in metastatic progression. Tumor cells will successfully form life-threatening metastases when they undergo sequential steps along a journey from the primary tumor to distant organs. From a biomechanics standpoint, growth, invasion, intravasation, circulation, arrest/adhesion, and extravasation of tumor cells demand particular cell-mechanical properties in order to survive and complete the metastatic cascade. With metastatic cells usually being softer than their non-malignant counterparts, high deformability for both the cell and its nucleus is thought to offer a significant advantage for metastatic potential. However, it is still unclear whether there is a finely tuned but fixed mechanical state that accommodates all mechanical features required for survival throughout the cascade or whether tumor cells need to dynamically refine their properties and intracellular components at each new step encountered. Here, we review the various mechanical requirements successful cancer cells might need to fulfill along their journey and speculate on the possibility that they dynamically adapt their properties accordingly. The mechanical signature of a successful cancer cell might actually be its ability to adapt to the successive microenvironmental constraints along the different steps of the journey.
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Affiliation(s)
- Valentin Gensbittel
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Martin Kräter
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Sébastien Harlepp
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Ignacio Busnelli
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Jochen Guck
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany.
| | - Jacky G Goetz
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.
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208
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Abstract
Miniaturization and integration of optical tweezers are attractive. Optical fiber-based trapping systems allow optical traps to be realized in miniature systems, but the optical traps in these systems lack reliability or mobility. Here, we present the all-fiber modular optical tweezers (AFMOTs), in which an optical trap can be reliably created and freely moved on a sample substrate. Two inclined optical fibers are permanently fixed to a common board, rendering a modular system where fiber alignments are maintained over months. The freely movable optical trap allows particles to be trapped in their native locations. As a demonstration, we applied AFMOTs to trap and deform freely floating individual cells. By the cell mechanical responses, we differentiated the nontumorigenic breast epithelial cell line (MCF10A) from its cancerous PTEN mutants (MCF10 PTEN-/-). To further expand the functionalities, three modalities of AFMOTs are demonstrated by changing the types of fibers for both the optical trap creation and particle position detection. As a miniature and modular system that creates a reliable and mobile optical trap, AFMOTs can find potential applications ranging from point-of-care diagnostics to education, as well as helping transition the optical trapping technology from the research lab to the field.
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209
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Dutta D, Palmer XL, Ortega-Rodas J, Balraj V, Dastider IG, Chandra S. Biomechanical and Biophysical Properties of Breast Cancer Cells Under Varying Glycemic Regimens. Breast Cancer (Auckl) 2020; 14:1178223420972362. [PMID: 33239879 PMCID: PMC7672722 DOI: 10.1177/1178223420972362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/12/2020] [Indexed: 01/27/2023] Open
Abstract
Diabetes accelerates cancer cell proliferation and metastasis, particularly for cancers of the pancreas, liver, breast, colon, and skin. While pathways linking the 2 disease conditions have been explored extensively, there is a lack of information on whether there could be cytoarchitectural changes induced by glucose which predispose cancer cells to aggressive phenotypes. It was thus hypothesized that exposure to diabetes/high glucose alters the biomechanical and biophysical properties of cancer cells more than the normal cells, which aids in advancing the cancer. For this study, atomic force microscopy indentation was used through microscale probing of multiple human breast cancer cells (MCF-7, MDA-MB-231), and human normal mammary epithelial cells (MCF-10A), under different levels of glycemic stress. These were used to study both benign and malignant breast tissue behaviors. Benign cells (MCF-10A) recorded higher Young's modulus values than malignant cells (MCF-7 and MDA-231) under normoglycemic conditions, which agrees with the current literature. Moreover, exposure to high glucose (for 48 hours) decreased Young's modulus in both benign and malignant cells, to the effect that the cancer cells showed a complete loss in elasticity with high glucose. This provides a possible insight into a link between glycemic stress and cytoskeletal strength. This work suggests that reducing glycemic stress in cancer patients and those at risk can prove beneficial in restoring normal cytoskeletal structure.
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Affiliation(s)
- Diganta Dutta
- Department of Physics and Astronomy, University of Nebraska at Kearney, Kearney, NE, USA
| | - Xavier-Lewis Palmer
- Department of Biomedical Engineering, Old Dominion University, Norfolk, VA, USA
| | - Jose Ortega-Rodas
- Department of Biology, University of Nebraska at Kearney, Kearney, NE, USA
| | | | | | - Surabhi Chandra
- Department of Biology, University of Nebraska at Kearney, Kearney, NE, USA
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210
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Actin as a Target to Reduce Cell Invasiveness in Initial Stages of Metastasis. Ann Biomed Eng 2020; 49:1342-1352. [PMID: 33145677 DOI: 10.1007/s10439-020-02679-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/22/2020] [Indexed: 12/21/2022]
Abstract
We demonstrate the relative roles of the cell cytoskeleton, and specific importance of actin in facilitating mechanical aspects of metastatic invasion. A crucial step in metastasis, the typically lethal spread of cancer to distant body-sites, is cell invasion through dense tissues composed of extracellular matrix and various non-cancerous cells. Cell invasion requires cell-cytoskeleton remodeling to facilitate dynamic morphological changes and force application. We have previously shown invasive cell subsets in heterogeneous samples can rapidly (2 h) and forcefully indent non-degradable, impenetrable, synthetic gels to cell-scale depths. The amounts of indenting cells and their attained depths provide the mechanical invasiveness of the sample, which as we have shown agrees with the in vitro metastatic potential and the in vivo metastatic risk in humans. To identify invasive force-application mechanisms, we evaluated changes in mechanical invasiveness following chemical perturbations targeting the structure and function of cytoskeleton elements and associated proteins. We evaluate effects on short-term (2-hr) indentations of single, well-spaced or closely situated cells as compared to long-time-scale Boyden chamber migration. We show that actomyosin inhibition may be used to reduce (mechanical) invasiveness of single or collectively invading cells, while actin-disruption may induce escape-response of treated single-cells, which may promote metastasis.
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211
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Dumitru AC, Mohammed D, Maja M, Yang J, Verstraeten S, del Campo A, Mingeot‐Leclercq M, Tyteca D, Alsteens D. Label-Free Imaging of Cholesterol Assemblies Reveals Hidden Nanomechanics of Breast Cancer Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2002643. [PMID: 33240781 PMCID: PMC7675049 DOI: 10.1002/advs.202002643] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/24/2020] [Indexed: 05/13/2023]
Abstract
Tumor cells present profound alterations in their composition, structural organization, and functional properties. A landmark of cancer cells is an overall altered mechanical phenotype, which so far are linked to changes in their cytoskeletal regulation and organization. Evidence exists that the plasma membrane (PM) of cancer cells also shows drastic changes in its composition and organization. However, biomechanical characterization of PM remains limited mainly due to the difficulties encountered to investigate it in a quantitative and label-free manner. Here, the biomechanical properties of PM of a series of MCF10 cell lines, used as a model of breast cancer progression, are investigated. Notably, a strong correlation between the cell PM elasticity and oncogenesis is observed. The altered membrane composition under cancer progression, as emphasized by the PM-associated cholesterol levels, leads to a stiffening of the PM that is uncoupled from the elastic cytoskeletal properties. Conversely, cholesterol depletion of metastatic cells leads to a softening of their PM, restoring biomechanical properties similar to benign cells. As novel therapies based on targeting membrane lipids in cancer cells represent a promising approach in the field of anticancer drug development, this method contributes to deciphering the functional link between PM lipid content and disease.
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Affiliation(s)
- Andra C. Dumitru
- Louvain Institute of Biomolecular Science and Technology (LIBST)Université catholique de LouvainLouvain‐la‐Neuve1348Belgium
| | - Danahe Mohammed
- Louvain Institute of Biomolecular Science and Technology (LIBST)Université catholique de LouvainLouvain‐la‐Neuve1348Belgium
| | - Mauriane Maja
- Cell Biology (CELL) Unit de Duve InstituteUniversité catholique de LouvainBrussels1200Belgium
| | - Jinsung Yang
- Louvain Institute of Biomolecular Science and Technology (LIBST)Université catholique de LouvainLouvain‐la‐Neuve1348Belgium
| | - Sandrine Verstraeten
- Cellular and Molecular Pharmacology Unit (FACM)Louvain Drug Research InstituteUniversité catholique de LouvainBrussels1200Belgium
| | - Aranzazu del Campo
- INM – Leibniz‐Institut für Neue Materialien gGmbHCampus D2 2Saarbrücken66123Germany
| | - Marie‐Paule Mingeot‐Leclercq
- Cellular and Molecular Pharmacology Unit (FACM)Louvain Drug Research InstituteUniversité catholique de LouvainBrussels1200Belgium
| | - Donatienne Tyteca
- Cell Biology (CELL) Unit de Duve InstituteUniversité catholique de LouvainBrussels1200Belgium
| | - David Alsteens
- Louvain Institute of Biomolecular Science and Technology (LIBST)Université catholique de LouvainLouvain‐la‐Neuve1348Belgium
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212
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Bacteria Residing at Root Canals Can Induce Cell Proliferation and Alter the Mechanical Properties of Gingival and Cancer Cells. Int J Mol Sci 2020; 21:ijms21217914. [PMID: 33114460 PMCID: PMC7672538 DOI: 10.3390/ijms21217914] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/20/2020] [Accepted: 10/20/2020] [Indexed: 12/11/2022] Open
Abstract
Understanding the importance of oral microbiota in human health and disease also leads to an expansion of the knowledge on functional, metabolic, and molecular alterations directly contributing to oral and systemic pathologies. To date, a compelling number of studies have documented the crucial role of some oral cavity-occurring microbes in the initiation and progression of cancers. Although this effect was noted primarily for Fusobacterium spp., the potential impact of other oral microbes is also worthy of investigation. In this study, we aimed to assess the effect of Enterococcus faecalis, Actinomyces odontolyticus, and Propionibacterium acnes on the proliferation capability and mechanical features of gingival cells and cell lines derived from lung, breast, and ovarian cancers. For this purpose, we incubated selected cell lines with heat-inactivated bacteria and supernatants collected from biofilms, cultured in both anaerobic and aerobic conditions, in the presence of surgically removed teeth and human saliva. The effect of oral bacteria on cell population growth is variable, with the highest growth-promoting abilities observed for E. faecalis in relation to human primary gingival fibroblasts (HGF) and lung cancer A549 cells, and P. acnes in relation to breast cancer MCF-7 and ovarian cancer SKOV-3 cells. Notably, this effect seems to depend on a delicate balance between the pro-stimulatory and toxic effects of bacterial-derived products. Regardless of the diverse effect of bacterial products on cellular proliferation capability, we observed significant alterations in stiffness of gingival and lung cancer cells stimulated with E. faecalis bacteria and corresponding biofilm supernatants, suggesting a novel molecular mechanism involved in the pathogenesis of diseases in oral cavities and tooth tissues. Accordingly, it is proposed that analysis of cancerogenic features of oral cavity bacteria should be multivariable and should include investigation of potential alterations in cell mechanical properties. These findings corroborate the important role of oral hygiene and root canal treatment to assure the healthy stage of oral microbiota.
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213
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Martinez L, Dhruv A, Lin L, Balaras E, Keidar M. Model for deformation of cells from external electric fields at or near resonant frequencies. Biomed Phys Eng Express 2020; 6. [PMID: 35091510 DOI: 10.1088/2057-1976/abc05e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 10/12/2020] [Indexed: 11/11/2022]
Abstract
This paper presents a numerical model to investigate the deformation of biological cells by applying external electric fields operating at or near cell resonant frequencies. Cells are represented as pseudo solids with high viscosity suspended in liquid media. The electric field source is an atmospheric plasma jet developed inhouse, for which the emitted energy distribution has been measured. Viscoelastic response is resolved in the entire cell structure by solving a deformation matrix assuming an isotropic material with a prescribed modulus of elasticity. To investigate cell deformation at resonant frequencies, one mode of natural cell oscillation is considered in which the cell membrane is made to radially move about its eigenfrequency. An electromagnetic wave source interacts with the cell and induces oscillation and viscoelastic response. The source carries energy in the form of a distribution function which couples a range of oscillating frequencies with electric field amplitudes. Results show that cell response may be increased by the external electric field operating at or near resonance. In the elastic regime, response increases until a steady threshold value, and the structure moves as a damped oscillator. Generally, this response is a function of both frequency and magnitude of the source, with a maximum effect found at resonance. To understand the full effect of the source energy spectrum, the system is solved by considering five frequency-amplitude couplings. Results show that the total solution is a nonlinear combination of the individual solutions. Additionally, sources with different signal phases are simulated to determine the effect of initial conditions on the evolution of the system, and the result suggests that there may be multiple solutions within the same order of magnitude for elastic response and velocity. Cell rupture from electric stress may occur during application given a high energy source.
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Affiliation(s)
- Luis Martinez
- Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Science, TheGeorge Washington University, Washington, DC 20052, United States of America
| | - Akash Dhruv
- Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Science, TheGeorge Washington University, Washington, DC 20052, United States of America
| | - Li Lin
- Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Science, TheGeorge Washington University, Washington, DC 20052, United States of America
| | - Elias Balaras
- Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Science, TheGeorge Washington University, Washington, DC 20052, United States of America
| | - Michael Keidar
- Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Science, TheGeorge Washington University, Washington, DC 20052, United States of America
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214
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Ghassemi P, Harris KS, Ren X, Foster BM, Langefeld CD, Kerr BA, Agah M. Comparative Study of Prostate Cancer Biophysical and Migratory Characteristics via Iterative Mechanoelectrical Properties (iMEP) and Standard Migration Assays. SENSORS AND ACTUATORS. B, CHEMICAL 2020; 321:128522. [PMID: 32863589 PMCID: PMC7455013 DOI: 10.1016/j.snb.2020.128522] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
This study reveals a new microfluidic biosensor consisting of a multi-constriction microfluidic device with embedded electrodes for measuring the biophysical attributes of single cells. The biosensing platform called the iterative mechano-electrical properties (iMEP) analyzer captures electronic records of biomechanical and bioelectrical properties of cells. The iMEP assay is used in conjunction with standard migration assays, such as chemotaxis-based Boyden chamber and scratch wound healing assays, to evaluate the migratory behavior and biophysical properties of prostate cancer cells. The three cell lines evaluated in the study each represent a stage in the standard progression of prostate cancer, while the fourth cell line serves as a normal/healthy counterpart. Neither the scratch assay nor the chemotaxis assay could fully differentiate the four cell lines. Furthermore, there was not a direct correlation between wound healing rate or the migratory rate with the cells' metastatic potential. However, the iMEP assay, through its multiparametric dataset, could distinguish between all four cell line populations with p-value < 0.05. Further studies are needed to determine if iMEP signatures can be used for a wider range of human cells to assess the tumorigenicity of a cell population or the metastatic potential of cancer cells.
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Affiliation(s)
- Parham Ghassemi
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Koran S. Harris
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157, United States
| | - Xiang Ren
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Brittni M. Foster
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157, United States
| | - Carl D. Langefeld
- Department of Biostatistics and Data Science, Division of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, 27157, United States
| | - Bethany A. Kerr
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157, United States
| | - Masoud Agah
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
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215
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Bischoff P, Kornhuber M, Dunst S, Zell J, Fauler B, Mielke T, Taubenberger AV, Guck J, Oelgeschläger M, Schönfelder G. Estrogens Determine Adherens Junction Organization and E-Cadherin Clustering in Breast Cancer Cells via Amphiregulin. iScience 2020; 23:101683. [PMID: 33163938 PMCID: PMC7607435 DOI: 10.1016/j.isci.2020.101683] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/18/2020] [Accepted: 10/12/2020] [Indexed: 12/17/2022] Open
Abstract
Estrogens play an important role in the development and progression of human cancers, particularly in breast cancer. Breast cancer progression depends on the malignant destabilization of adherens junctions (AJs) and disruption of tissue integrity. We found that estrogen receptor alpha (ERα) inhibition led to a striking spatial reorganization of AJs and microclustering of E-Cadherin (E-Cad) in the cell membrane of breast cancer cells. This resulted in increased stability of AJs and cell stiffness and a reduction of cell motility. These effects were actomyosin-dependent and reversible by estrogens. Detailed investigations showed that the ERα target gene and epidermal growth factor receptor (EGFR) ligand Amphiregulin (AREG) essentially regulates AJ reorganization and E-Cad microclustering. Our results not only describe a biological mechanism for the organization of AJs and the modulation of mechanical properties of cells but also provide a new perspective on how estrogens and anti-estrogens might influence the formation of breast tumors. ERα inhibition causes adherens junction (AJ) reorganization through AREG and EGFR AJ reorganization coincides with microclustering of E-Cadherin at cell membranes AJ reorganization and microclustering of E-Cadherin are actomyosin dependent AJ reorganization correlates with increased cell stiffness and reduced motility
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Affiliation(s)
- Philip Bischoff
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.,Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany
| | - Marja Kornhuber
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.,Freie Universität Berlin, 14195 Berlin, Germany
| | - Sebastian Dunst
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany
| | - Jakob Zell
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.,Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany
| | - Beatrix Fauler
- Max Planck Institute for Molecular Genetics, Microscopy and Cryo-Electron Microscopy Service Group, 14195 Berlin, Germany
| | - Thorsten Mielke
- Max Planck Institute for Molecular Genetics, Microscopy and Cryo-Electron Microscopy Service Group, 14195 Berlin, Germany
| | - Anna V Taubenberger
- Biotechnology Center, Technische Universität Dresden, 01307 Dresden, Germany
| | - Jochen Guck
- Max Planck Institute for the Science of Light, Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
| | - Michael Oelgeschläger
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany
| | - Gilbert Schönfelder
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.,Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany
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216
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Targeting Mechanotransduction in Osteosarcoma: A Comparative Oncology Perspective. Int J Mol Sci 2020; 21:ijms21207595. [PMID: 33066583 PMCID: PMC7589883 DOI: 10.3390/ijms21207595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 12/13/2022] Open
Abstract
Mechanotransduction is the process in which cells can convert extracellular mechanical stimuli into biochemical changes within a cell. While this a normal process for physiological development and function in many organ systems, tumour cells can exploit this process to promote tumour progression. Here we summarise the current state of knowledge of mechanotransduction in osteosarcoma (OSA), the most common primary bone tumour, referencing both human and canine models and other similar mesenchymal malignancies (e.g., Ewing sarcoma). Specifically, we discuss the mechanical properties of OSA cells, the pathways that these cells utilise to respond to external mechanical cues, and mechanotransduction-targeting strategies tested in OSA so far. We point out gaps in the literature and propose avenues to address them. Understanding how the physical microenvironment influences cell signalling and behaviour will lead to the improved design of strategies to target the mechanical vulnerabilities of OSA cells.
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217
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Raju SR, Balakrishnan S, Kollimada S, Chandrashekara KN, Jampani A. Anti-tumor effects of Artemisia nilagirica extract on MDA-MB-231 breast cancer cells: deciphering the biochemical and biomechanical properties via TGF-β upregulation. Heliyon 2020; 6:e05088. [PMID: 33072905 PMCID: PMC7548430 DOI: 10.1016/j.heliyon.2020.e05088] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 08/14/2020] [Accepted: 09/24/2020] [Indexed: 01/07/2023] Open
Abstract
Purpose Artemisia nilagirica (AN), which is known to have antimicrobial, antioxidant, antiulcer, and anti-asthmatic properties, has been recently shown to have anti-cancer activity. However, the mechanism responsible for the anti-cancer property and its effect on cellular properties and functions are not known. Material and methods We have characterized the biochemical and biomechanical properties of MDA-MB-231 cells treated with the methanolic extract from AN. Results We show that AN-treatment decreases cell-eccentricity, increases expression of actin and microtubules, and do not affect cell-area. Increased expression of cytoskeletal proteins is known to change the mechanical properties of the cells, which was confirmed using micropipette aspiration and Atomic Force Microscopy. We identified the upregulation of the tumorigenic pathway (TGF-β) leading to activation of Rho-A as the molecular mechanism responsible for actin upregulation. Since the initial stages of TGF-β upregulation are known to suppress tumor growth by activating apoptosis, we hypothesized that the mechanism of cell death due to AN-treatment is through TGF-β activation. We have validated this hypothesis by partially recuing cell death through inhibition of TGF-β using Alk-5. Conclusion In summary, our study reveals the mechanism of action of Artemisia nilagirica using a synergy between biochemical and biomechanical techniques.
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Affiliation(s)
- Shilpa R Raju
- Department of Biotechnology, REVA University, Bengaluru, India.,Department of Mechanical Engineering, Indian Institute of Science, Bengaluru, India
| | | | - Somanna Kollimada
- Department of Mechanical Engineering, Indian Institute of Science, Bengaluru, India
| | - K N Chandrashekara
- Division of Plant Physiology and Biotechnology, UPASI Tea Research Foundation, Coimbatore, India
| | - Aruna Jampani
- Department of Biotechnology, REVA University, Bengaluru, India
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218
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Hosseini K, Taubenberger A, Werner C, Fischer‐Friedrich E. EMT-Induced Cell-Mechanical Changes Enhance Mitotic Rounding Strength. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2001276. [PMID: 33042748 PMCID: PMC7539203 DOI: 10.1002/advs.202001276] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/18/2020] [Indexed: 05/26/2023]
Abstract
To undergo mitosis successfully, most animal cells need to acquire a round shape to provide space for the mitotic spindle. This mitotic rounding relies on mechanical deformation of surrounding tissue and is driven by forces emanating from actomyosin contractility. Cancer cells are able to maintain successful mitosis in mechanically challenging environments such as the increasingly crowded environment of a growing tumor, thus, suggesting an enhanced ability of mitotic rounding in cancer. Here, it is shown that the epithelial-mesenchymal transition (EMT), a hallmark of cancer progression and metastasis, gives rise to cell-mechanical changes in breast epithelial cells. These changes are opposite in interphase and mitosis and correspond to an enhanced mitotic rounding strength. Furthermore, it is shown that cell-mechanical changes correlate with a strong EMT-induced change in the activity of Rho GTPases RhoA and Rac1. Accordingly, it is found that Rac1 inhibition rescues the EMT-induced cortex-mechanical phenotype. The findings hint at a new role of EMT in successful mitotic rounding and division in mechanically confined environments such as a growing tumor.
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Affiliation(s)
- Kamran Hosseini
- Biotechnology CenterTechnische Universität DresdenTatzberg 47–49Dresden01307Germany
- Cluster of Excellence Physics of LifeTechnische Universität DresdenDresden01062Germany
| | - Anna Taubenberger
- Biotechnology CenterTechnische Universität DresdenTatzberg 47–49Dresden01307Germany
| | - Carsten Werner
- Leibniz Institute of Polymer Research DresdenMax Bergmann CenterHohe Str. 6Dresden01069Germany
| | - Elisabeth Fischer‐Friedrich
- Biotechnology CenterTechnische Universität DresdenTatzberg 47–49Dresden01307Germany
- Cluster of Excellence Physics of LifeTechnische Universität DresdenDresden01062Germany
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219
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Jung W, Li J, Chaudhuri O, Kim T. Nonlinear Elastic and Inelastic Properties of Cells. J Biomech Eng 2020; 142:100806. [PMID: 32253428 PMCID: PMC7477719 DOI: 10.1115/1.4046863] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 03/27/2020] [Indexed: 12/15/2022]
Abstract
Mechanical forces play an important role in various physiological processes, such as morphogenesis, cytokinesis, and migration. Thus, in order to illuminate mechanisms underlying these physiological processes, it is crucial to understand how cells deform and respond to external mechanical stimuli. During recent decades, the mechanical properties of cells have been studied extensively using diverse measurement techniques. A number of experimental studies have shown that cells are far from linear elastic materials. Cells exhibit a wide variety of nonlinear elastic and inelastic properties. Such complicated properties of cells are known to emerge from unique mechanical characteristics of cellular components. In this review, we introduce major cellular components that largely govern cell mechanical properties and provide brief explanations of several experimental techniques used for rheological measurements of cell mechanics. Then, we discuss the representative nonlinear elastic and inelastic properties of cells. Finally, continuum and discrete computational models of cell mechanics, which model both nonlinear elastic and inelastic properties of cells, will be described.
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Affiliation(s)
- Wonyeong Jung
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907
| | - Jing Li
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907
| | - Ovijit Chaudhuri
- Department of Mechanical Engineering, Stanford University, 440 Escondido Mall, Stanford, CA 94305
| | - Taeyoon Kim
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907
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220
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Ombid RJL, Oyong GG, Cabrera EC, Espulgar WV, Saito M, Tamiya E, Pobre RF. In-vitro study of monocytic THP-1 leukemia cell membrane elasticity with a single-cell microfluidic-assisted optical trapping system. BIOMEDICAL OPTICS EXPRESS 2020; 11:6027-6037. [PMID: 33150003 PMCID: PMC7587289 DOI: 10.1364/boe.402526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/20/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
We studied the elastic profile of monocytic THP-1 leukemia cells using a microfluidic-assisted optical trap. A 2-µm fused silica bead was optically trapped to mechanically dent an immobilized single THP-1 monocyte sieved on a 15-µm microfluidic capture chamber. Cells treated with Zeocin and untreated cells underwent RT-qPCR analysis to determine cell apoptosis through gene expression in relation to each cell's deformation profile. Results showed that untreated cells with 43.05 ± 6.68 Pa are more elastic compared to the treated cells with 15.81 ± 2.94 Pa. THP-1 monocyte's elastic modulus is indicative of cell apoptosis shown by upregulated genes after Zeocin treatment. This study clearly showed that the developed technique can be used to distinguish between cells undergoing apoptosis and cells not undergoing apoptosis and which may apply to the study of other cells and other cell states as well.
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Affiliation(s)
- Ric John L. Ombid
- OPTICS Research Unit, CENSER, De La Salle University (DLSU), Manila, Philippines
- Optics and Instrumentation Physics Laboratory, Physics Department, DLSU, Manila, Philippines
| | - Glenn G. Oyong
- OPTICS Research Unit, CENSER, De La Salle University (DLSU), Manila, Philippines
- Molecular Science Unit Laboratory, CENSER, DLSU, Manila, Philippines
| | - Esperanza C. Cabrera
- Biology Department, DLSU, Manila, Philippines
- Molecular Science Unit Laboratory, CENSER, DLSU, Manila, Philippines
| | - Wilfred V. Espulgar
- Department of Applied Physics, Graduate School of Engineering, Osaka University, Japan
| | - Masato Saito
- Department of Applied Physics, Graduate School of Engineering, Osaka University, Japan
- Advanced Photonics and Biosensing Open Innovation Laboratory, AIST-Osaka University, Photonics Center, Osaka University, Osaka 565-0871, Japan
| | - Eiichi Tamiya
- Advanced Photonics and Biosensing Open Innovation Laboratory, AIST-Osaka University, Photonics Center, Osaka University, Osaka 565-0871, Japan
- The Institute of Scientific and Industrial Research, Osaka University, Japan
| | - Romeric F. Pobre
- OPTICS Research Unit, CENSER, De La Salle University (DLSU), Manila, Philippines
- Optics and Instrumentation Physics Laboratory, Physics Department, DLSU, Manila, Philippines
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221
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Asgharzadeh P, Birkhold AI, Trivedi Z, Özdemir B, Reski R, Röhrle O. A NanoFE simulation-based surrogate machine learning model to predict mechanical functionality of protein networks from live confocal imaging. Comput Struct Biotechnol J 2020; 18:2774-2788. [PMID: 33101614 PMCID: PMC7559262 DOI: 10.1016/j.csbj.2020.09.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/12/2020] [Accepted: 09/13/2020] [Indexed: 02/07/2023] Open
Abstract
Sub-cellular mechanics plays a crucial role in a variety of biological functions and dysfunctions. Due to the strong structure-function relationship in cytoskeletal protein networks, light can be shed on their mechanical functionality by investigating their structures. Here, we present a data-driven approach employing a combination of confocal live imaging of fluorescent tagged protein networks, in silico mechanical experiments and machine learning to investigate this relationship. Our designed image processing and nanoFE mechanical simulation framework resolves the structure and mechanical behaviour of cytoskeletal networks and the developed gradient boosting surrogate models linking network structure to its functionality. In this study, for the first time, we perform mechanical simulations of Filamentous Temperature Sensitive Z (FtsZ) complex protein networks with realistic network geometry depicting its skeletal functionality inside organelles (here, chloroplasts) of the moss Physcomitrella patens. Training on synthetically produced simulation data enables predicting the mechanical characteristics of FtsZ network purely based on its structural features (R2⩾0.93), therefore allowing to extract structural principles enabling specific mechanical traits of FtsZ, such as load bearing and resistance to buckling failure in case of large network deformation.
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Affiliation(s)
- Pouyan Asgharzadeh
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany.,Stuttgart Center for Simulation Science (SC SimTech), Stuttgart, Germany
| | - Annette I Birkhold
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany.,Stuttgart Center for Simulation Science (SC SimTech), Stuttgart, Germany
| | - Zubin Trivedi
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
| | - Bugra Özdemir
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Freiburg, Germany
| | - Ralf Reski
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Freiburg, Germany.,Cluster of Excellence livMatS @ FIT - Freiburg Centre for Interactive Materials and Bioinspired Technologies, Freiburg, Germany
| | - Oliver Röhrle
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany.,Stuttgart Center for Simulation Science (SC SimTech), Stuttgart, Germany
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222
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Mierke CT. Mechanical Cues Affect Migration and Invasion of Cells From Three Different Directions. Front Cell Dev Biol 2020; 8:583226. [PMID: 33043017 PMCID: PMC7527720 DOI: 10.3389/fcell.2020.583226] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 08/24/2020] [Indexed: 12/20/2022] Open
Abstract
Cell migration and invasion is a key driving factor for providing essential cellular functions under physiological conditions or the malignant progression of tumors following downward the metastatic cascade. Although there has been plentiful of molecules identified to support the migration and invasion of cells, the mechanical aspects have not yet been explored in a combined and systematic manner. In addition, the cellular environment has been classically and frequently assumed to be homogeneous for reasons of simplicity. However, motility assays have led to various models for migration covering only some aspects and supporting factors that in some cases also include mechanical factors. Instead of specific models, in this review, a more or less holistic model for cell motility in 3D is envisioned covering all these different aspects with a special emphasis on the mechanical cues from a biophysical perspective. After introducing the mechanical aspects of cell migration and invasion and presenting the heterogeneity of extracellular matrices, the three distinct directions of cell motility focusing on the mechanical aspects are presented. These three different directions are as follows: firstly, the commonly used invasion tests using structural and structure-based mechanical environmental signals; secondly, the mechano-invasion assay, in which cells are studied by mechanical forces to migrate and invade; and thirdly, cell mechanics, including cytoskeletal and nuclear mechanics, to influence cell migration and invasion. Since the interaction between the cell and the microenvironment is bi-directional in these assays, these should be accounted in migration and invasion approaches focusing on the mechanical aspects. Beyond this, there is also the interaction between the cytoskeleton of the cell and its other compartments, such as the cell nucleus. In specific, a three-element approach is presented for addressing the effect of mechanics on cell migration and invasion by including the effect of the mechano-phenotype of the cytoskeleton, nucleus and the cell's microenvironment into the analysis. In precise terms, the combination of these three research approaches including experimental techniques seems to be promising for revealing bi-directional impacts of mechanical alterations of the cellular microenvironment on cells and internal mechanical fluctuations or changes of cells on the surroundings. Finally, different approaches are discussed and thereby a model for the broad impact of mechanics on cell migration and invasion is evolved.
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Affiliation(s)
- Claudia Tanja Mierke
- Faculty of Physics and Earth Science, Peter Debye Institute of Soft Matter Physics, Biological Physics Division, University of Leipzig, Leipzig, Germany
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223
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Sengul E, Elitas M. Single-Cell Mechanophenotyping in Microfluidics to Evaluate Behavior of U87 Glioma Cells. MICROMACHINES 2020; 11:mi11090845. [PMID: 32932941 PMCID: PMC7569913 DOI: 10.3390/mi11090845] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/03/2020] [Accepted: 09/10/2020] [Indexed: 12/20/2022]
Abstract
Integration of microfabricated, single-cell resolution and traditional, population-level biological assays will be the future of modern techniques in biology that will enroll in the evolution of biology into a precision scientific discipline. In this study, we developed a microfabricated cell culture platform to investigate the indirect influence of macrophages on glioma cell behavior. We quantified proliferation, morphology, motility, migration, and deformation properties of glioma cells at single-cell level and compared these results with population-level data. Our results showed that glioma cells obtained slightly slower proliferation, higher motility, and extremely significant deformation capability when cultured with 50% regular growth medium and 50% macrophage-depleted medium. When the expression levels of E-cadherin and Vimentin proteins were measured, it was verified that observed mechanophenotypic alterations in glioma cells were not due to epithelium to mesenchymal transition. Our results were consistent with previously reported enormous heterogeneity of U87 glioma cell line. Herein, for the first time, we quantified the change of deformation indexes of U87 glioma cells using microfluidic devices for single-cells analysis.
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Affiliation(s)
- Esra Sengul
- Faculty of Engineering and Natural Sciences, Sabanci University, 34956 Istanbul, Turkey;
| | - Meltem Elitas
- Faculty of Engineering and Natural Sciences, Sabanci University, 34956 Istanbul, Turkey;
- Nanotechnology Research and Application Center, Sabanci University, 34956 Istanbul, Turkey
- Correspondence: ; Tel.: +90-538-810-2930
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224
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Choi YH, Kim JA, Lee W. Changes of Inertial Focusing Position in a Triangular Channel Depending on Droplet Deformability and Size. MICROMACHINES 2020; 11:E839. [PMID: 32906834 PMCID: PMC7570260 DOI: 10.3390/mi11090839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 12/17/2022]
Abstract
Studies on cell separation with inertial microfluidics are often carried out with solid particles initially. When this condition is applied for actual cell separations, the efficiency typically becomes lower because of the polydispersity and deformability of cells. Therefore, the understanding of deformability-induced lift force is essential to achieve highly efficient cell separation. We investigate the inertial focusing positions of viscous droplets in a triangular channel while varying Re, deformability, and droplet size. With increasing Re and decreasing droplet size, the top focusing position splits and shifts along the sidewalls. The threshold size of the focusing position splitting increases for droplets with larger deformability. The overall path of the focusing position shifts with increasing Re also has a strong dependency on deformability. Consequently, droplets of the same size can have different focusing positions depending on their deformability. The feasibility of deformability-based cell separation is shown by different focusing positions of MCF10a and MCF7 cells.
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Affiliation(s)
- Yo-han Choi
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea;
| | - Jeong-ah Kim
- Department of Physics, KAIST, Daejeon 34141, Korea;
| | - Wonhee Lee
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea;
- Department of Physics, KAIST, Daejeon 34141, Korea;
- Department of Bio and Brain Engineering, KAIST, Daejeon 34141, Korea
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225
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Jaeschke A, Jacobi A, Lawrence M, Risbridger G, Frydenberg M, Williams E, Vela I, Hutmacher D, Bray L, Taubenberger A. Cancer-associated fibroblasts of the prostate promote a compliant and more invasive phenotype in benign prostate epithelial cells. Mater Today Bio 2020; 8:100073. [PMID: 32984808 PMCID: PMC7498830 DOI: 10.1016/j.mtbio.2020.100073] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/30/2020] [Accepted: 08/07/2020] [Indexed: 01/04/2023] Open
Abstract
Reciprocal interactions between prostate epithelial cells and their adjacent stromal microenvironment not only are essential for tissue homeostasis but also play a key role in tumor development and progression. Malignant transformation is associated with the formation of a reactive stroma where cancer-associated fibroblasts (CAFs) induce matrix remodeling and thereby provide atypical biochemical and biomechanical signals to epithelial cells. Previous work has been focused on the cellular and molecular phenotype as well as on matrix stiffness and remodeling, providing potential targets for cancer therapeutics. So far, biomechanical changes in CAFs and adjacent epithelial cells of the prostate have not been explored. Here, we compared the mechanical properties of primary prostatic CAFs and patient-matched non-malignant prostate tissue fibroblasts (NPFs) using atomic force microscopy (AFM) and real-time deformability cytometry (RT-FDC). It was found that CAFs exhibit an increased apparent Young's modulus, coinciding with an altered architecture of the cytoskeleton compared with NPFs. In contrast, co-cultures of benign prostate epithelial (BPH-1) cells with CAFs resulted in a decreased stiffness of the epithelial cells, as well as an elongated morphological phenotype, when compared with co-cultures with NPFs. Moreover, the presence of CAFs increased proliferation and invasion of epithelial cells, features typically associated with tumor progression. Altogether, this study provides novel insights into the mechanical interactions between epithelial cells with the malignant prostate microenvironment, which could potentially be explored for new diagnostic approaches.
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Affiliation(s)
- A. Jaeschke
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Kelvin Grove, Australia
- School of Mechanical, Medical and Process Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, Australia
| | - A. Jacobi
- Biotechnology Center, Technische Universität Dresden, Germany
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - M.G. Lawrence
- Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia
| | - G.P. Risbridger
- Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia
| | - M. Frydenberg
- Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
- Australian Urology Associates, Melbourne, Victoria, Australia
- Department of Urology, Cabrini Health, Malvern, Victoria, Australia
| | - E.D. Williams
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Kelvin Grove, Australia
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology (QUT), Kelvin Grove, Australia
- Translational Research Institute, Woolloongabba, Australia
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, Australia
| | - I. Vela
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Kelvin Grove, Australia
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology (QUT), Kelvin Grove, Australia
- Translational Research Institute, Woolloongabba, Australia
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, Australia
- Department of Urology, Princess Alexandra Hospital, Woolloongabba, Australia
| | - D.W. Hutmacher
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Kelvin Grove, Australia
- School of Mechanical, Medical and Process Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, Australia
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, Australia
| | - L.J. Bray
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Kelvin Grove, Australia
- School of Mechanical, Medical and Process Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, Australia
| | - A. Taubenberger
- Biotechnology Center, Technische Universität Dresden, Germany
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226
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4-Hydroxyacetophenone modulates the actomyosin cytoskeleton to reduce metastasis. Proc Natl Acad Sci U S A 2020; 117:22423-22429. [PMID: 32848073 DOI: 10.1073/pnas.2014639117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Metastases are the cause of the vast majority of cancer deaths. In the metastatic process, cells migrate to the vasculature, intravasate, extravasate, and establish metastatic colonies. This pattern of spread requires the cancer cells to change shape and to navigate tissue barriers. Approaches that block this mechanical program represent new therapeutic avenues. We show that 4-hydroxyacetophenone (4-HAP) inhibits colon cancer cell adhesion, invasion, and migration in vitro and reduces the metastatic burden in an in vivo model of colon cancer metastasis to the liver. Treatment with 4-HAP activates nonmuscle myosin-2C (NM2C) (MYH14) to alter actin organization, inhibiting the mechanical program of metastasis. We identify NM2C as a specific therapeutic target. Pharmacological control of myosin isoforms is a promising approach to address metastatic disease, one that may be readily combined with other therapeutic strategies.
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227
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Barenholz-Cohen T, Merkher Y, Haj J, Shechter D, Kirchmeier D, Shaked Y, Weihs D. Lung mechanics modifications facilitating metastasis are mediated in part by breast cancer-derived extracellular vesicles. Int J Cancer 2020; 147:2924-2933. [PMID: 32700789 DOI: 10.1002/ijc.33229] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 07/10/2020] [Accepted: 07/14/2020] [Indexed: 12/20/2022]
Abstract
Tumor microenvironment-mechanics greatly affect tumor-cell characteristics such as invasion and proliferation. We and others have previously shown that after chemotherapy, tumor cells shed more extracellular vesicles (EVs), leading to tumor growth and even spread, via angiogenesis and the mobilization of specific bone-marrow-derived cells contributing to metastasis. However, physical, mechanobiological and mechanostructural changes at premetastatic sites that may support tumor cell seeding, have yet to be determined. Here, we collected tumor-derived extracellular vesicles (tEV) from breast carcinoma cells exposed to paclitaxel chemotherapy, and tested their effects on tissue mechanics (eg, elasticity and stiffness) of likely metastatic organs in cancer-free mice, using shear rheometry. Cancer-free mice were injected with saline or with tEVs from untreated cells and lung tissue demonstrated widely variable, viscoelastic mechanics, being more elastic than viscous. Contrastingly, tEVs from chemotherapy-exposed cells induced more uniform, viscoelastic lung mechanics, with lower stiffness and viscosity; interestingly, livers were significantly stiffer than both controls. We observe statistically significant differences in softening of lung samples from all three groups under increasing strain-amplitudes and in their stiffening under increasing strain-frequencies; the groups reach similar values at high strain amplitudes and frequencies, indicating local changes in tissue microstructure. Evaluation of genes associated with the extracellular matrix and fibronectin protein-expression revealed potential compositional changes underlying the altered mechanics. Thus, we propose that tEVs, even without cancer cells, contribute to metastasis by changing microstructures at distant organs. This is done partially by altering the composition and mechanostructure of tissues to support tumor cell invasion and seeding.
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Affiliation(s)
- Tamar Barenholz-Cohen
- Faculty of Biomedical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Yulia Merkher
- Faculty of Biomedical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Jozafina Haj
- Rappaport Faculty of Medicine, Technion-Integrated Cancer Center, Technion - Israel Institute of Technology, Haifa, Israel
| | - Dvir Shechter
- Rappaport Faculty of Medicine, Technion-Integrated Cancer Center, Technion - Israel Institute of Technology, Haifa, Israel
| | - Daniela Kirchmeier
- Faculty of Biomedical Engineering, Technion - Israel Institute of Technology, Haifa, Israel.,Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences Krems, Krems an der Donau, Austria
| | - Yuval Shaked
- Rappaport Faculty of Medicine, Technion-Integrated Cancer Center, Technion - Israel Institute of Technology, Haifa, Israel
| | - Daphne Weihs
- Faculty of Biomedical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
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228
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Taubenberger AV, Baum B, Matthews HK. The Mechanics of Mitotic Cell Rounding. Front Cell Dev Biol 2020; 8:687. [PMID: 32850812 PMCID: PMC7423972 DOI: 10.3389/fcell.2020.00687] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/06/2020] [Indexed: 12/21/2022] Open
Abstract
When animal cells enter mitosis, they round up to become spherical. This shape change is accompanied by changes in mechanical properties. Multiple studies using different measurement methods have revealed that cell surface tension, intracellular pressure and cortical stiffness increase upon entry into mitosis. These cell-scale, biophysical changes are driven by alterations in the composition and architecture of the contractile acto-myosin cortex together with osmotic swelling and enable a mitotic cell to exert force against the environment. When the ability of cells to round is limited, for example by physical confinement, cells suffer severe defects in spindle assembly and cell division. The requirement to push against the environment to create space for spindle formation is especially important for cells dividing in tissues. Here we summarize the evidence and the tools used to show that cells exert rounding forces in mitosis in vitro and in vivo, review the molecular basis for this force generation and discuss its function for ensuring successful cell division in single cells and for cells dividing in normal or diseased tissues.
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Affiliation(s)
- Anna V. Taubenberger
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Buzz Baum
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Helen K. Matthews
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
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229
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Boers T, van der Putten J, Struyvenberg M, Fockens K, Jukema J, Schoon E, van der Sommen F, Bergman J, de With P. Improving Temporal Stability and Accuracy for Endoscopic Video Tissue Classification Using Recurrent Neural Networks. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4133. [PMID: 32722344 PMCID: PMC7436238 DOI: 10.3390/s20154133] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/09/2020] [Accepted: 07/20/2020] [Indexed: 01/10/2023]
Abstract
Early Barrett's neoplasia are often missed due to subtle visual features and inexperience of the non-expert endoscopist with such lesions. While promising results have been reported on the automated detection of this type of early cancer in still endoscopic images, video-based detection using the temporal domain is still open. The temporally stable nature of video data in endoscopic examinations enables to develop a framework that can diagnose the imaged tissue class over time, thereby yielding a more robust and improved model for spatial predictions. We show that the introduction of Recurrent Neural Network nodes offers a more stable and accurate model for tissue classification, compared to classification on individual images. We have developed a customized Resnet18 feature extractor with four types of classifiers: Fully Connected (FC), Fully Connected with an averaging filter (FC Avg(n = 5)), Long Short Term Memory (LSTM) and a Gated Recurrent Unit (GRU). Experimental results are based on 82 pullback videos of the esophagus with 46 high-grade dysplasia patients. Our results demonstrate that the LSTM classifier outperforms the FC, FC Avg(n = 5) and GRU classifier with an average accuracy of 85.9% compared to 82.2%, 83.0% and 85.6%, respectively. The benefit of our novel implementation for endoscopic tissue classification is the inclusion of spatio-temporal information for improved and robust decision making, and it is the first step towards full temporal learning of esophageal cancer detection in endoscopic video.
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Affiliation(s)
- Tim Boers
- Department of Electrical Engineering, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands; (J.v.d.P.); (F.v.d.S.); (P.d.W.)
| | - Joost van der Putten
- Department of Electrical Engineering, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands; (J.v.d.P.); (F.v.d.S.); (P.d.W.)
| | - Maarten Struyvenberg
- Amsterdam University Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.S.); (K.F.); (J.J.); (J.B.)
| | - Kiki Fockens
- Amsterdam University Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.S.); (K.F.); (J.J.); (J.B.)
| | - Jelmer Jukema
- Amsterdam University Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.S.); (K.F.); (J.J.); (J.B.)
| | - Erik Schoon
- Catharina Hospital, Michelangelolaan 2, 5623 EJ Eindhoven, The Netherlands;
| | - Fons van der Sommen
- Department of Electrical Engineering, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands; (J.v.d.P.); (F.v.d.S.); (P.d.W.)
| | - Jacques Bergman
- Amsterdam University Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.S.); (K.F.); (J.J.); (J.B.)
| | - Peter de With
- Department of Electrical Engineering, Eindhoven University of Technology, Groene Loper 3, 5612 AE Eindhoven, The Netherlands; (J.v.d.P.); (F.v.d.S.); (P.d.W.)
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230
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Piergiovanni M, Galli V, Holzner G, Stavrakis S, DeMello A, Dubini G. Deformation of leukaemia cell lines in hyperbolic microchannels: investigating the role of shear and extensional components. LAB ON A CHIP 2020; 20:2539-2548. [PMID: 32567621 DOI: 10.1039/d0lc00166j] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The mechanical properties of cells are of enormous interest in a diverse range of physio and pathological situations of clinical relevance. Unsurprisingly, a variety of microfluidic platforms have been developed in recent years to study the deformability of cells, most commonly employing pure shear or extensional flows, with and without direct contact of the cells with channel walls. Herein, we investigate the effects of shear and extensional flow components on fluid-induced cell deformation by means of three microchannel geometries. In the case of hyperbolic microchannels, cell deformation takes place in a flow with constant extensional rate, under non-zero shear conditions. A sudden expansion at the microchannel terminus allows one to evaluate shape recovery subsequent to deformation. Comparison with other microchannel shapes, that induce either pure shear (straight channel) or pure extensional (cross channel) flows, reveals different deformation modes. Such an analysis is used to confirm the softening and stiffening effects of common treatments, such as cytochalasin D and formalin on cell deformability. In addition to an experimental analysis of leukaemia cell deformability, computational fluid dynamic simulations are used to deconvolve the role of the aforementioned flow components in the cell deformation dynamics. In general terms, the current study can be used as a guide for extracting deformation/recovery dynamics of leukaemia cell lines when exposed to various fluid dynamic conditions.
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Affiliation(s)
- Monica Piergiovanni
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, piazza Leonardo da Vinci, 32 - 20133 Milan, Italy.
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231
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Huang W, Tan M, Wang Y, Liu L, Pan Y, Li J, Ouyang M, Long C, Qu X, Liu H, Liu C, Wang J, Deng L, Xiang Y, Qin X. Increased intracellular Cl - concentration improves airway epithelial migration by activating the RhoA/ROCK Pathway. Theranostics 2020; 10:8528-8540. [PMID: 32754261 PMCID: PMC7392015 DOI: 10.7150/thno.46002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 06/24/2020] [Indexed: 12/19/2022] Open
Abstract
In the airway, Cl- is the most abundant anion and is critically involved in transepithelial transport. The correlation of the abnormal expression and activation of chloride channels (CLCs), such as cystic fibrosis transmembrane conductance regulators (CFTRs), anoctamin-1, and CLC-2, with cell migration capability suggests a relationship between defective Cl- transport and epithelial wound repair. However, whether a correlation exists between intracellular Cl- and airway wound repair capability has not been explored thus far, and the underlying mechanisms involved in this relationship are not fully defined. Methods: In this work, the alteration of intracellular chloride concentration ([Cl-]i) was measured by using a chloride-sensitive fluorescent probe (N-[ethoxycarbonylmethyl]-6-methoxyquinolium bromide). Results: We found that clamping with high [Cl-]i and 1 h of treatment with the CLC inhibitor CFTR blocker CFTRinh-172 and chloride intracellular channel inhibitor IAA94 increased intracellular Cl- concentration ([Cl-]i) in airway epithelial cells. This effect improved epithelial cell migration. In addition, increased [Cl-]i in cells promoted F-actin reorganization, decreased cell stiffness, and improved RhoA activation and LIMK1/2 phosphorylation. Treatment with the ROCK inhibitor of Y-27632 and ROCK1 siRNA significantly attenuated the effects of increased [Cl-]i on LIMK1/2 activation and cell migration. In addition, intracellular Ca2+ concentration was unaffected by [Cl-]i clamping buffers and CFTRinh-172 and IAA94. Conclusion: Taken together, these results suggested that Cl- accumulation in airway epithelial cells could activate the RhoA/ROCK/LIMK cascade to induce F-actin reorganization, down-regulate cell stiffness, and improve epithelial migration.
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Affiliation(s)
- Wenjie Huang
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
- Affiliated Liutie Central Hospital of Guangxi medical university, Liuzhou, Guangxi 545007, China
| | - Meiling Tan
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Yue Wang
- Changzhou Key Laboratory of Respiratory Medical Engineering, Institute of Biomedical Engineering and Health Sciences, Changzhou, Jiangsu 213164, China
- School of Nursing, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Lei Liu
- Changzhou Key Laboratory of Respiratory Medical Engineering, Institute of Biomedical Engineering and Health Sciences, Changzhou, Jiangsu 213164, China
| | - Yan Pan
- Changzhou Key Laboratory of Respiratory Medical Engineering, Institute of Biomedical Engineering and Health Sciences, Changzhou, Jiangsu 213164, China
| | - Jingjing Li
- Changzhou Key Laboratory of Respiratory Medical Engineering, Institute of Biomedical Engineering and Health Sciences, Changzhou, Jiangsu 213164, China
| | - Mingxing Ouyang
- Changzhou Key Laboratory of Respiratory Medical Engineering, Institute of Biomedical Engineering and Health Sciences, Changzhou, Jiangsu 213164, China
| | - Chunjiao Long
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Xiangping Qu
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Huijun Liu
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Chi Liu
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Jia Wang
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Linhong Deng
- Changzhou Key Laboratory of Respiratory Medical Engineering, Institute of Biomedical Engineering and Health Sciences, Changzhou, Jiangsu 213164, China
| | - Yang Xiang
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
| | - Xiaoqun Qin
- School of Basic Medicine, Central South University, Changsha, Hunan 410078, China
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232
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Scharf E, Dremel J, Kuschmierz R, Czarske J. Video-rate lensless endoscope with self-calibration using wavefront shaping. OPTICS LETTERS 2020; 45:3629-3632. [PMID: 32630916 DOI: 10.1364/ol.394873] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Lensless fiber endoscopes are of great importance for keyhole imaging. Coherent fiber bundles (CFB) can be used in endoscopes as remote phased arrays to capture images. One challenge is to image at high speed while correcting aberrations induced by the CFB. We propose the combination of digital optical phase conjugation, using a spatial light modulator, with fast scanning, for which a 2D galvo scanner and an adaptive lens are employed. We achieve the transmission of laser and image scanning through the CFB. Video-rate imaging at 20 Hz in 2D with subcellular resolution is demonstrated in 3D with 1 Hz. The sub-millimeter-diameter scanning endoscope has a great potential in biomedicine, for manipulation, e.g., in optogenetics, as well as in imaging.
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233
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Ferreira JPS, Kuang M, Parente MPL, Natal Jorge RM, Wang R, Eppell SJ, Damaser M. Altered mechanics of vaginal smooth muscle cells due to the lysyl oxidase-like1 knockout. Acta Biomater 2020; 110:175-187. [PMID: 32335309 DOI: 10.1016/j.actbio.2020.03.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 03/26/2020] [Accepted: 03/31/2020] [Indexed: 01/04/2023]
Abstract
The remodeling mechanisms that cause connective tissue of the vaginal wall, consisting mostly of smooth muscle, to weaken after vaginal delivery are not fully understood. Abnormal remodeling after delivery can contribute to development of pelvic organ prolapse and other pelvic floor disorders. The present study used vaginal smooth muscle cells (vSMCs) isolated from knockout mice lacking the expression of the lysyl oxidase-like1 (LOXL1) enzyme, a well-characterized animal model for pelvic organ prolapse. We tested if vaginal smooth muscle cells from LOXL1 knockout mice have altered mechanics including stiffness and surface adhesion. Using atomic force microscopy, we performed nanoindentations on both isolated and confluent cells to evaluate the effect of LOXL1 knockout on in vitro cultures of vSMCs cells from nulliparous mice. The results show that LOXL1 knockout vSMCs have increased stiffness in pre-confluent but decreased stiffness in confluent cultures (p* < 0.05) and significant decreased surface adhesion in pre-confluent cultures (p* < 0.05). This study provides evidence that the weakening of vaginal connective tissue in the absense of LOXL1 changes the mechanical properties of the vSMCs. STATEMENT OF SIGNIFICANCE: Pelvic organ prolapse is a common condition affecting millions of women worldwide, which significantly impacts their quality of life. Alterations in vaginal and pelvic floor mechanical properties can change their ability to support the pelvic organs. This study provides evidence of altered stiffness of vaginal smooth muscle cells from mice resembling pelvic organ prolapse. The results from this study set a foundation to develop pathophysiology-driven therapies focused on the interplay between smooth muscle mechanics and extracellular matrix remodeling.
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Affiliation(s)
- J P S Ferreira
- Department of Mechanical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal; Institute of Science and Innovation in Mechanical and Industrial Engineering, Porto, Portugal; Department of Biomedical Engineering, Lerner Research Institute and Glickman Urological Institute, Cleveland Clinic Foundation, OH, USA.
| | - M Kuang
- Department of Biomedical Engineering, Lerner Research Institute and Glickman Urological Institute, Cleveland Clinic Foundation, OH, USA
| | - M P L Parente
- Department of Mechanical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal; Institute of Science and Innovation in Mechanical and Industrial Engineering, Porto, Portugal
| | - R M Natal Jorge
- Department of Mechanical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal; Institute of Science and Innovation in Mechanical and Industrial Engineering, Porto, Portugal
| | - R Wang
- Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA
| | - S J Eppell
- Department of Biomedical Engineering, Case Western Reserve, Cleveland, OH, USA
| | - M Damaser
- Department of Biomedical Engineering, Lerner Research Institute and Glickman Urological Institute, Cleveland Clinic Foundation, OH, USA; Department of Biomedical Engineering, Case Western Reserve, Cleveland, OH, USA; Advanced Platform Technology Center, Louis Stokes Cleveland Veteran's Administration Medical Center, Cleveland, OH, USA.
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234
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Heydarian A, Milani D, Moein Fatemi SM. An investigation of the viscoelastic behavior of MCF-10A and MCF-7 cells. Biochem Biophys Res Commun 2020; 529:432-436. [PMID: 32703447 DOI: 10.1016/j.bbrc.2020.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 06/02/2020] [Indexed: 10/24/2022]
Abstract
Breast cancer is the most frequent female malignancy in the world. In this regard, cancer detection by assessing the biomechanical properties of cells is a promising method in oncology. Cell state can be identified by studying viscosity behavior; however, a more complex understanding of cells requires a profound insight into the solidity and fluidity of cells via the characterization of cell viscoelasticity. The present study aimed to compare the viscoelasticity of healthy human breast epithelial cells (MCF-10A) with that of cancerous cells (MCF 7). The experiment included the addition of nano magnetic particles (NMP) to the cell culture environment and placement of the Petri Dishes under a microscope after the completion of primary culture stages and, ultimately, adoption of a magnetic tweezer technique to perform a creep test. A viscoelastic model of cells was suggested with discrete differential equations for both groups of healthy and cancerous cells after obtaining information about cell membrane movements and performing image processes on these data. A comparison of cell stiffness was made under two conditions of static and dynamic. According to the findings, cancerous static stiffness was lower than that of healthy cells by a factor of 3.5. The creep test results showed that MCF 7 cells would exhibit solid-like behavior. At a higher gel point frequency, these cells emerged more solidity compared to their corresponding healthy cells. The obtained results revealed the clear changes in cancerous cells' viscoelastic properties and the potential alterations of their cytoskeleton.
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Affiliation(s)
- Ashkan Heydarian
- Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
| | - Dornaz Milani
- Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
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235
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Islam M, Raj A, McFarland B, Brink HM, Ciciliano J, Fay M, Myers DR, Flowers C, Waller EK, Lam W, Alexeev A, Sulchek T. Stiffness based enrichment of leukemia cells using microfluidics. APL Bioeng 2020; 4:036101. [PMID: 32637856 PMCID: PMC7332299 DOI: 10.1063/1.5143436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 06/08/2020] [Indexed: 01/06/2023] Open
Abstract
To improve the survival rate of cancer patients, new diagnosis strategies are necessary to detect lower levels of cancer cells before and after treatment regimens. The scarcity of diseased cells, particularly in residual disease after treatment, demands highly sensitive detection approaches or the ability to enrich the diseased cells in relation to normal cells. We report a label-free microfluidic approach to enrich leukemia cells from healthy cells using inherent differences in cell biophysical properties. The microfluidic device consists of a channel with an array of diagonal ridges that recurrently compress and translate flowing cells in proportion to cell stiffness. Using devices optimized for acute T cell leukemia model Jurkat, the stiffer white blood cells were translated orthogonally to the channel length, while softer leukemia cells followed hydrodynamic flow. The device enriched Jurkat leukemia cells from white blood cells with an enrichment factor of over 760. The sensitivity, specificity, and accuracy of the device were found to be >0.8. The values of sensitivity and specificity could be adjusted by selecting one or multiple outlets for analysis. We demonstrate that low levels of Jurkat leukemia cells (1 in 104 white blood cells) could be more quickly detected using flow cytometry by using the stiffness sorting pre-enrichment. In a second mode of operation, the device was implemented to sort resistive leukemia cells from both drug-sensitive leukemia cells and normal white blood cells. Therefore, microfluidic biomechanical sorting can be a useful tool to enrich leukemia cells that may improve downstream analyses.
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Affiliation(s)
- Muhymin Islam
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, Georgia 30332-0405, USA
| | - Abhishek Raj
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, Georgia 30332-0405, USA
| | - Brynn McFarland
- The School of Biological Sciences, Georgia Institute of Technology, 310 Ferst Drive, Atlanta, Georgia 30332-0535, USA
| | - Hannah Maxine Brink
- The School of Biological Sciences, Georgia Institute of Technology, 310 Ferst Drive, Atlanta, Georgia 30332-0535, USA
| | - Jordan Ciciliano
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, Atlanta, Georgia 30332-0535, USA
| | - Meredith Fay
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, Atlanta, Georgia 30332-0535, USA
| | - David Richard Myers
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, Atlanta, Georgia 30332-0535, USA
| | - Christopher Flowers
- Winship Cancer Institute, Emory School of Medicine, 1365 Clifton NE Rd.: Atlanta, Georgia 30322, USA
| | - Edmund K Waller
- Winship Cancer Institute, Emory School of Medicine, 1365 Clifton NE Rd.: Atlanta, Georgia 30322, USA
| | - Wilbur Lam
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, Atlanta, Georgia 30332-0535, USA
| | - Alexander Alexeev
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive, Atlanta, Georgia 30332-0405, USA
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236
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Dubay R, Fiering J, Darling EM. Effect of elastic modulus on inertial displacement of cell-like particles in microchannels. BIOMICROFLUIDICS 2020; 14:044110. [PMID: 32774585 PMCID: PMC7402708 DOI: 10.1063/5.0017770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 07/21/2020] [Indexed: 05/07/2023]
Abstract
Label-free microfluidic-based cell sorters leverage innate differences among cells (e.g., size and stiffness), to separate one cell type from another. This sorting step is crucial for many cell-based applications. Polystyrene-based microparticles (MPs) are the current gold standard for calibrating flow-based cell sorters and analyzers; however, the deformation behavior of these rigid materials is drastically different from that of living cells. Given this discrepancy in stiffness, an alternative calibration particle that better reflects cell elasticity is needed for the optimization of new and existing microfluidic devices. Here, we describe the fabrication of cell-like, mechanically tunable MPs and demonstrate their utility in quantifying differences in inertial displacement within a microfluidic constriction device as a function of particle elastic modulus, for the first time. Monodisperse, fluorescent, cell-like microparticles that replicate the size and modulus of living cells were fabricated from polyacrylamide within a microfluidic droplet generator and characterized via optical and atomic force microscopy. Trajectories of our cell-like MPs were mapped within the constriction device to predict where living cells of similar size/modulus would move. Calibration of the device with our MPs showed that inertial displacement depends on both particle size and modulus, with large/soft MPs migrating further toward the channel centerline than small/stiff MPs. The mapped trajectories also indicated that MP modulus contributed proportionally more to particle displacement than size, for the physiologically relevant ranges tested. The large shift in focusing position quantified here emphasizes the need for physiologically relevant, deformable MPs for calibrating and optimizing microfluidic separation platforms.
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Affiliation(s)
| | - J. Fiering
- Draper, Cambridge, Massachusetts 02139, USA
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237
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Higgins G, Peres J, Abdalrahman T, Zaman MH, Lang DM, Prince S, Franz T. Cytoskeletal tubulin competes with actin to increase deformability of metastatic melanoma cells. Exp Cell Res 2020; 394:112154. [PMID: 32598874 DOI: 10.1016/j.yexcr.2020.112154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 06/08/2020] [Accepted: 06/22/2020] [Indexed: 01/07/2023]
Abstract
The formation of membrane protrusions during migration is reliant upon the cells' cytoskeletal structure and stiffness. It has been reported that actin disruption blocks protrusion and decreases cell stiffness whereas microtubule disruption blocks protrusion but increases stiffness in several cell types. In melanoma, cell migration is of concern as this cancer spreads unusually rapidly during early tumour development. The aim of this study was to characterise motility, structural properties and stiffness of human melanoma cells at radial growth phase (RGP), vertical growth phase (VGP), and metastatic stage (MET) in two-dimensional in vitro environments. Wound assays, western blotting and mitochondrial particle tracking were used to assess cell migration, cytoskeletal content and intracellular fluidity. Our results indicate that cell motility increase with increasing disease stage. Despite their different motility, RGP and VGP cells exhibit similar fluidity, actin and tubulin levels. MET cells, however, display increased fluidity which was associated with increased actin and tubulin content. Our findings demonstrate an interplay between actin and microtubule activity and their role in increasing motility of cells while minimizing cell stiffness at advanced disease stage. In earlier disease stages, cell stiffness may however not serve as an indicator of migratory capabilities.
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Affiliation(s)
- Ghodeejah Higgins
- Division of Biomedical Engineering, Department of Human Biology, University of Cape Town, South Africa
| | - Jade Peres
- Division of Cell Biology, Department of Human Biology, University of Cape Town, South Africa
| | - Tamer Abdalrahman
- Division of Biomedical Engineering, Department of Human Biology, University of Cape Town, South Africa
| | - Muhammad H Zaman
- Department of Biomedical Engineering and Howard Hughes Medical Institute, Boston University, USA
| | - Dirk M Lang
- Division of Physiological Sciences, Department of Human Biology, University of Cape Town, South Africa
| | - Sharon Prince
- Division of Cell Biology, Department of Human Biology, University of Cape Town, South Africa
| | - Thomas Franz
- Division of Biomedical Engineering, Department of Human Biology, University of Cape Town, South Africa; Bioengineering Science Research Group, Engineering Sciences, University of Southampton, UK.
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Merkher Y, Horesh Y, Abramov Z, Shleifer G, Ben-Ishay O, Kluger Y, Weihs D. Rapid Cancer Diagnosis and Early Prognosis of Metastatic Risk Based on Mechanical Invasiveness of Sampled Cells. Ann Biomed Eng 2020; 48:2846-2858. [DOI: 10.1007/s10439-020-02547-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/09/2020] [Indexed: 11/29/2022]
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239
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Urbanska M, Muñoz HE, Shaw Bagnall J, Otto O, Manalis SR, Di Carlo D, Guck J. A comparison of microfluidic methods for high-throughput cell deformability measurements. Nat Methods 2020; 17:587-593. [PMID: 32341544 PMCID: PMC7275893 DOI: 10.1038/s41592-020-0818-8] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 03/23/2020] [Indexed: 12/14/2022]
Abstract
The mechanical phenotype of a cell is an inherent biophysical marker of its state and function, with many applications in basic and applied biological research. Microfluidics-based methods have enabled single-cell mechanophenotyping at throughputs comparable to those of flow cytometry. Here, we present a standardized cross-laboratory study comparing three microfluidics-based approaches for measuring cell mechanical phenotype: constriction-based deformability cytometry (cDC), shear flow deformability cytometry (sDC) and extensional flow deformability cytometry (xDC). All three methods detect cell deformability changes induced by exposure to altered osmolarity. However, a dose-dependent deformability increase upon latrunculin B-induced actin disassembly was detected only with cDC and sDC, which suggests that when exposing cells to the higher strain rate imposed by xDC, cellular components other than the actin cytoskeleton dominate the response. The direct comparison presented here furthers our understanding of the applicability of the different deformability cytometry methods and provides context for the interpretation of deformability measurements performed using different platforms.
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Affiliation(s)
- Marta Urbanska
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Hector E Muñoz
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Josephine Shaw Bagnall
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Oliver Otto
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
- Zentrum für Innovationskompetenz: Humorale Immunreaktionen in kardiovaskulären Erkrankungen, Universität Greifswald, Greifswald, Germany
| | - Scott R Manalis
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Dino Di Carlo
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, USA.
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.
- Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, CA, USA.
| | - Jochen Guck
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany.
- Max Planck Institute for the Science of Light and Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany.
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240
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Fischer T, Hayn A, Mierke CT. Effect of Nuclear Stiffness on Cell Mechanics and Migration of Human Breast Cancer Cells. Front Cell Dev Biol 2020; 8:393. [PMID: 32548118 PMCID: PMC7272586 DOI: 10.3389/fcell.2020.00393] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 04/29/2020] [Indexed: 12/18/2022] Open
Abstract
The migration and invasion of cancer cells through 3D confined extracellular matrices is coupled to cell mechanics and the mechanics of the extracellular matrix. Cell mechanics is mainly determined by both the mechanics of the largest organelle in the cell, the nucleus, and the cytoskeletal architecture of the cell. Hence, cytoskeletal and nuclear mechanics are the major contributors to cell mechanics. Among other factors, steric hindrances of the extracellular matrix confinement are supposed to affect nuclear mechanics and thus also influence cell mechanics. Therefore, we propose that the percentage of invasive cells and their invasion depths into loose and dense 3D extracellular matrices is regulated by both nuclear and cytoskeletal mechanics. In order to investigate the effect of both nuclear and cytoskeletal mechanics on the overall cell mechanics, we firstly altered nuclear mechanics by the chromatin de-condensing reagent Trichostatin A (TSA) and secondly altered cytoskeletal mechanics by addition of actin polymerization inhibitor Latrunculin A and the myosin inhibitor Blebbistatin. In fact, we found that TSA-treated MDA-MB-231 human breast cancer cells increased their invasion depth in dense 3D extracellular matrices, whereas the invasion depths in loose matrices were decreased. Similarly, the invasion depths of TSA-treated MCF-7 human breast cancer cells in dense matrices were significantly increased compared to loose matrices, where the invasion depths were decreased. These results are also valid in the presence of a matrix-metalloproteinase inhibitor GM6001. Using atomic force microscopy (AFM), we found that the nuclear stiffnesses of both MDA-MB-231 and MCF-7 breast cancer cells were pronouncedly higher than their cytoskeletal stiffness, whereas the stiffness of the nucleus of human mammary epithelial cells was decreased compared to their cytoskeleton. TSA treatment reduced cytoskeletal and nuclear stiffness of MCF-7 cells, as expected. However, a softening of the nucleus by TSA treatment may induce a stiffening of the cytoskeleton of MDA-MB-231 cells and subsequently an apparent stiffening of the nucleus. Inhibiting actin polymerization using Latrunculin A revealed a softer nucleus of MDA-MB-231 cells under TSA treatment. This indicates that the actin-dependent cytoskeletal stiffness seems to be influenced by the TSA-induced nuclear stiffness changes. Finally, the combined treatment with TSA and Latrunculin A further justifies the hypothesis of apparent nuclear stiffening, indicating that cytoskeletal mechanics seem to be regulated by nuclear mechanics.
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Affiliation(s)
- Tony Fischer
- Biological Physics Division, Peter Debye Institute of Soft Matter Physics, Faculty of Physics and Earth Sciences, Leipzig University, Leipzig, Germany
| | - Alexander Hayn
- Biological Physics Division, Peter Debye Institute of Soft Matter Physics, Faculty of Physics and Earth Sciences, Leipzig University, Leipzig, Germany
| | - Claudia Tanja Mierke
- Biological Physics Division, Peter Debye Institute of Soft Matter Physics, Faculty of Physics and Earth Sciences, Leipzig University, Leipzig, Germany
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241
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Raudenska M, Balvan J, Fojtu M, Gumulec J, Masarik M. Unexpected therapeutic effects of cisplatin. Metallomics 2020; 11:1182-1199. [PMID: 31098602 DOI: 10.1039/c9mt00049f] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cisplatin is a widely used chemotherapeutic agent that is clinically approved to fight both carcinomas and sarcomas. It has relatively high efficiency in treating ovarian cancers and metastatic testicular cancers. It is generally accepted that the major mechanism of cisplatin anti-cancer action is DNA damage. However, cisplatin is also effective in metastatic cancers and should, therefore, affect slow-cycling cancer stem cells in some way. In this review, we focused on the alternative effects of cisplatin that can support a good therapeutic response. First, attention was paid to the effects of cisplatin at the cellular level such as changes in intracellular pH and cellular mechanical properties. Alternative cellular targets of cisplatin, and the effects of cisplatin on cancer cell metabolism and ER stress were also discussed. Furthermore, the impacts of cisplatin on the tumor microenvironment and in the whole organism context were reviewed. In this review, we try to reveal possible causes of the unexpected effectiveness of this anti-cancer drug.
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Affiliation(s)
- Martina Raudenska
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic.
| | - Jan Balvan
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic. and Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic and Central European Institute of Technology, Brno University of Technology, Purkynova 656/123, CZ-612 00 Brno, Czech Republic
| | - Michaela Fojtu
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic.
| | - Jaromir Gumulec
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic. and Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic and Central European Institute of Technology, Brno University of Technology, Purkynova 656/123, CZ-612 00 Brno, Czech Republic
| | - Michal Masarik
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic. and Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic and BIOCEV, First Faculty of Medicine, Charles University, Průmyslová 595, CZ-252 50 Vestec, Czech Republic
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242
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Schibber EF, Mittelstein DR, Gharib M, Shapiro MG, Lee PP, Ortiz M. A dynamical model of oncotripsy by mechanical cell fatigue: selective cancer cell ablation by low-intensity pulsed ultrasound. Proc Math Phys Eng Sci 2020; 476:20190692. [PMID: 32398930 DOI: 10.1098/rspa.2019.0692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 03/23/2020] [Indexed: 01/16/2023] Open
Abstract
The method of oncotripsy, first proposed in Heyden & Ortiz (Heyden & Ortiz 2016 J. Mech. Phys. Solids 92, 164-175 (doi:10.1016/j.jmps.2016.04.016)), exploits aberrations in the material properties and morphology of cancerous cells in order to ablate them selectively by means of tuned low-intensity pulsed ultrasound. We propose the dynamical model of oncotripsy that follows as an application of cell dynamics, statistical mechanical theory of network elasticity and 'birth-death' kinetics to describe the processes of damage and repair of the cytoskeleton. We also develop a reduced dynamical model that approximates the three-dimensional dynamics of the cell and facilitates parametric studies, including sensitivity analysis and process optimization. We show that the dynamical model predicts-and provides a conceptual basis for understanding-the oncotripsy effect and other trends in the data of Mittelstein et al. (Mittelstein et al. 2019 Appl. Phys. Lett. 116, 013701 (doi:10.1063/1.5128627)), for cells in suspension, including the dependence of cell-death curves on cell and process parameters.
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Affiliation(s)
- E F Schibber
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - D R Mittelstein
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - M Gharib
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - M G Shapiro
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - P P Lee
- Department of Immuno-Oncology, City of Hope National Medical Center, 1500 E Duarte Road, Duarte, CA 91010, USA
| | - M Ortiz
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
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243
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Connolly S, Newport D, McGourty K. The mechanical responses of advecting cells in confined flow. BIOMICROFLUIDICS 2020; 14:031501. [PMID: 32454924 PMCID: PMC7200165 DOI: 10.1063/5.0005154] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 04/21/2020] [Indexed: 05/03/2023]
Abstract
Fluid dynamics have long influenced cells in suspension. Red blood cells and white blood cells are advected through biological microchannels in both the cardiovascular and lymphatic systems and, as a result, are subject to a wide variety of complex fluidic forces as they pass through. In vivo, microfluidic forces influence different biological processes such as the spreading of infection, cancer metastasis, and cell viability, highlighting the importance of fluid dynamics in the blood and lymphatic vessels. This suggests that in vitro devices carrying cell suspensions may influence the viability and functionality of cells. Lab-on-a-chip, flow cytometry, and cell therapies involve cell suspensions flowing through microchannels of approximately 100-800 μ m. This review begins by examining the current fundamental theories and techniques behind the fluidic forces and inertial focusing acting on cells in suspension, before exploring studies that have investigated how these fluidic forces affect the reactions of suspended cells. In light of these studies' findings, both in vivo and in vitro fluidic cell microenvironments shall also be discussed before concluding with recommendations for the field.
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Affiliation(s)
- S Connolly
- School of Engineering, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - D Newport
- School of Engineering, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
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244
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Artificially decreasing cortical tension generates aneuploidy in mouse oocytes. Nat Commun 2020; 11:1649. [PMID: 32245998 PMCID: PMC7125192 DOI: 10.1038/s41467-020-15470-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 03/10/2020] [Indexed: 01/28/2023] Open
Abstract
Human and mouse oocytes’ developmental potential can be predicted by their mechanical properties. Their development into blastocysts requires a specific stiffness window. In this study, we combine live-cell and computational imaging, laser ablation, and biophysical measurements to investigate how deregulation of cortex tension in the oocyte contributes to early developmental failure. We focus on extra-soft cells, the most common defect in a natural population. Using two independent tools to artificially decrease cortical tension, we show that chromosome alignment is impaired in extra-soft mouse oocytes, despite normal spindle morphogenesis and dynamics, inducing aneuploidy. The main cause is a cytoplasmic increase in myosin-II activity that could sterically hinder chromosome capture. We describe here an original mode of generation of aneuploidies that could be very common in oocytes and could contribute to the high aneuploidy rate observed during female meiosis, a leading cause of infertility and congenital disorders. The developmental potential of human and murine oocytes is predicted by their mechanical properties. Here the authors show that artificial reduction of cortex tension produces aneuploid mouse oocytes and speculate that this may contribute to the high aneuploidy rate typical of female meiosis.
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245
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Vitali V, Nava G, Zanchetta G, Bragheri F, Crespi A, Osellame R, Bellini T, Cristiani I, Minzioni P. Integrated Optofluidic Chip for Oscillatory Microrheology. Sci Rep 2020; 10:5831. [PMID: 32242060 PMCID: PMC7118116 DOI: 10.1038/s41598-020-62628-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 03/05/2020] [Indexed: 11/24/2022] Open
Abstract
We propose and demonstrate an on-chip optofluidic device allowing active oscillatory microrheological measurements with sub-μL sample volume, low cost and high flexibility. Thanks to the use of this optofluidic microrheometer it is possible to measure the viscoelastic properties of complex fluids in the frequency range 0.01-10 Hz at different temperatures. The system is based on the optical forces exerted on a microbead by two counterpropagating infrared laser beams. The core elements of the optical part, integrated waveguides and an optical modulator, are fabricated by fs-laser writing on a glass substrate. The system performance is validated by measuring viscoelastic solutions of aqueous worm-like micelles composed by Cetylpyridinium Chloride (CPyCl) and Sodium Salicylate (NaSal).
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Affiliation(s)
- Valerio Vitali
- University of Pavia, Dept. of Electrical, Computer and Biomedical Engineering, Pavia, 27100, Italy
| | - Giovanni Nava
- University of Milano, Dept. of Medical Biotechnology and Translational Medicine, Milano, 20129, Italy
| | - Giuliano Zanchetta
- University of Milano, Dept. of Medical Biotechnology and Translational Medicine, Milano, 20129, Italy
| | - Francesca Bragheri
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche (IFN-CNR), Milano, 20133, Italy
| | - Andrea Crespi
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche (IFN-CNR), Milano, 20133, Italy
- Dipartimento di Fisica, Politecnico di Milano, Milano, 20133, Italy
| | - Roberto Osellame
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche (IFN-CNR), Milano, 20133, Italy
- Dipartimento di Fisica, Politecnico di Milano, Milano, 20133, Italy
| | - Tommaso Bellini
- University of Milano, Dept. of Medical Biotechnology and Translational Medicine, Milano, 20129, Italy
| | - Ilaria Cristiani
- University of Pavia, Dept. of Electrical, Computer and Biomedical Engineering, Pavia, 27100, Italy
| | - Paolo Minzioni
- University of Pavia, Dept. of Electrical, Computer and Biomedical Engineering, Pavia, 27100, Italy.
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246
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Schibber EF, Mittelstein DR, Gharib M, Shapiro MG, Lee PP, Ortiz M. A dynamical model of oncotripsy by mechanical cell fatigue: selective cancer cell ablation by low-intensity pulsed ultrasound. PROCEEDINGS. MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2020. [PMID: 32398930 DOI: 10.1063/1.5128627] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
The method of oncotripsy, first proposed in Heyden & Ortiz (Heyden & Ortiz 2016 J. Mech. Phys. Solids 92, 164-175 (doi:10.1016/j.jmps.2016.04.016)), exploits aberrations in the material properties and morphology of cancerous cells in order to ablate them selectively by means of tuned low-intensity pulsed ultrasound. We propose the dynamical model of oncotripsy that follows as an application of cell dynamics, statistical mechanical theory of network elasticity and 'birth-death' kinetics to describe the processes of damage and repair of the cytoskeleton. We also develop a reduced dynamical model that approximates the three-dimensional dynamics of the cell and facilitates parametric studies, including sensitivity analysis and process optimization. We show that the dynamical model predicts-and provides a conceptual basis for understanding-the oncotripsy effect and other trends in the data of Mittelstein et al. (Mittelstein et al. 2019 Appl. Phys. Lett. 116, 013701 (doi:10.1063/1.5128627)), for cells in suspension, including the dependence of cell-death curves on cell and process parameters.
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Affiliation(s)
- E F Schibber
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - D R Mittelstein
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - M Gharib
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - M G Shapiro
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - P P Lee
- Department of Immuno-Oncology, City of Hope National Medical Center, 1500 E Duarte Road, Duarte, CA 91010, USA
| | - M Ortiz
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
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247
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Bashant KR, Toepfner N, Day CJ, Mehta NN, Kaplan MJ, Summers C, Guck J, Chilvers ER. The mechanics of myeloid cells. Biol Cell 2020; 112:103-112. [DOI: 10.1111/boc.201900084] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 12/18/2019] [Accepted: 01/03/2020] [Indexed: 01/05/2023]
Affiliation(s)
- Kathleen R Bashant
- Department of MedicineUniversity of Cambridge Cambridge UK
- Systemic Autoimmunity BranchNational Institute of Arthritis and Musculoskeletal and Skin DiseasesNational Institutes of Health Bethesda Maryland USA
| | - Nicole Toepfner
- Center for Molecular and Cellular BioengineeringBiotechnology Center, Technische Universität Dresden Dresden Germany
- Department of PediatricsUniversity Clinic Carl Gustav Carus, Technische Universität Dresden Dresden Germany
| | | | - Nehal N Mehta
- National Heart Lung and Blood InstituteNational Institutes of Health Bethesda MD USA
| | - Mariana J Kaplan
- Systemic Autoimmunity BranchNational Institute of Arthritis and Musculoskeletal and Skin DiseasesNational Institutes of Health Bethesda Maryland USA
| | | | - Jochen Guck
- Max‐Planck‐Institut für die Physik des Lichts & Max‐Planck‐Zentrum für Physik und Medizin Erlangen Germany
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248
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Kiio TM, Park S. Nano-scientific Application of Atomic Force Microscopy in Pathology: from Molecules to Tissues. Int J Med Sci 2020; 17:844-858. [PMID: 32308537 PMCID: PMC7163363 DOI: 10.7150/ijms.41805] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 02/26/2020] [Indexed: 12/28/2022] Open
Abstract
The advantages of atomic force microscopy (AFM) in biological research are its high imaging resolution, sensitivity, and ability to operate in physiological conditions. Over the past decades, rigorous studies have been performed to determine the potential applications of AFM techniques in disease diagnosis and prognosis. Many pathological conditions are accompanied by alterations in the morphology, adhesion properties, mechanical compliances, and molecular composition of cells and tissues. The accurate determination of such alterations can be utilized as a diagnostic and prognostic marker. Alteration in cell morphology represents changes in cell structure and membrane proteins induced by pathologic progression of diseases. Mechanical compliances are also modulated by the active rearrangements of cytoskeleton or extracellular matrix triggered by disease pathogenesis. In addition, adhesion is a critical step in the progression of many diseases including infectious and neurodegenerative diseases. Recent advances in AFM techniques have demonstrated their ability to obtain molecular composition as well as topographic information. The quantitative characterization of molecular alteration in biological specimens in terms of disease progression provides a new avenue to understand the underlying mechanisms of disease onset and progression. In this review, we have highlighted the application of diverse AFM techniques in pathological investigations.
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Affiliation(s)
| | - Soyeun Park
- College of Pharmacy, Keimyung University, 1095 Dalgubeoldaero, Daegu 42601, Republic of Korea
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249
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Evaluation of autofluorescence and photodynamic diagnosis in assessment of bladder lesions. Photodiagnosis Photodyn Ther 2020; 30:101719. [PMID: 32165336 DOI: 10.1016/j.pdpdt.2020.101719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 02/16/2020] [Accepted: 03/06/2020] [Indexed: 12/24/2022]
Abstract
The ability to detect and diagnose bladder cancer early and precisely is crucial for effective treatment. The aim of this study is to assess the utility of optical biopsy performed with autofluorescence cystoscopy (AFC) using the Onco-LIFE system with numerical color values (NCVs) and by ALA/PDD. Histopathological examination of material obtained during TURBT and/or biopsy of the bladder was carried out in 251 patients. In the case of 35 patients, the selection of the specimen collected for histopathological examination was based using ALA/PDD. In the remaining 216 patients, tissue was collected based on the findings of AFC with NCV. Using AFC, the observed NCV ranged from 0 to 3.86; the highest mean NCV was observed in neoplastic muscle invasive lesions and was equal to 3.18. Furthermore, non-muscle invasive tumors were characterized by a mean NCV equal to 1.54. Tissue with inflammation, metaplasia, and healthy tissue demonstrated significantly lower mean NCV values. The presence of a muscle-invasive tumor increased the NCV by approximately 2.86 compared to healthy tissue. The rates of postoperative complications depend on the examining operator and are observed more often, as much as 65.7 % during ALA/PDD. AFC with NCV using the Onco-LIFE system, as well as ALA/PDD are helpful tools for early diagnosis of bladder precancerous and cancer lesions and for performing targeted biopsies. A significant correlation was found between lesion NCV index and the grade of dysplasia or tumor malignancy. Tissue with inflammation, metaplasia, and healthy tissue demonstrated significantly lower mean NCV values. AFE with NCV have a significantly higher sensitivity than specificity. Low rates of postoperative complications are correlated to the experience of the endoscopist and with AFE/NCV in comparison of ALA/PDD.
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250
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Ghassemi P, Ren X, Foster BM, Kerr BA, Agah M. Post-enrichment circulating tumor cell detection and enumeration via deformability impedance cytometry. Biosens Bioelectron 2020; 150:111868. [PMID: 31767345 PMCID: PMC6957725 DOI: 10.1016/j.bios.2019.111868] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/07/2019] [Accepted: 11/08/2019] [Indexed: 02/05/2023]
Abstract
Circulating tumor cells (CTCs) in blood can provide valuable information when detecting, diagnosing, and monitoring cancer. This paper describes a system that consists of a constriction-based microfluidic sensor with embedded electrodes that can detect and enumerate cancer cells in blood. The biosensor measures impedance in terms of magnitude and phase at multiple frequencies as cells transit through the constriction channel. Cancer cells deform as they move through while blood cells remain intact, thus generating differential impedance profiles that can be used for detecting and counting CTCs. Two versions of this device are reported, one where the electrodes are embedded into the disposable microfluidic channel, and the other in which the disposable chip is externally fixed to a reusable substrate housing the electrodes. Both configurations were tested by spiking breast or prostate cancer cells into murine blood, and both detected all tumor cells passing through the narrow channels while being able to differentiate between the two cell lines. The chip in its current format has a throughput of 1 μL/min. While the throughput is scalable by integrating more constriction channels in parallel, the presented assay is intended for post-enrichment label-free enumeration and characterization of CTCs.
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Affiliation(s)
- Parham Ghassemi
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, 24061, United States.
| | - Xiang Ren
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, 24061, United States.
| | - Brittni M Foster
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, United States.
| | - Bethany A Kerr
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, United States.
| | - Masoud Agah
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, 24061, United States.
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