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Ji X, Ding W, Wang J, Zhou B, Li Y, Jiang W, Pan H, Gu J, Sun X. Application of intraoperative radiotherapy for malignant glioma. Cancer Radiother 2023; 27:425-433. [PMID: 37344258 DOI: 10.1016/j.canrad.2023.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 01/25/2023] [Accepted: 01/29/2023] [Indexed: 06/23/2023]
Abstract
Malignant glioma is characterized by rapid tumor cell proliferation and high recurrence risk. In terms of its treatment, the therapeutic effects of maximum resection and postoperative radiotherapy with adjuvant chemotherapy as well as many other new therapeutic techniques such as antiangiogenic therapy and immunotherapy remain poor. Glioma recurrence, especially local recurrence, is an important reason of glioma treatment failure. Intraoperative radiotherapy (IORT) enables exclusion of radiation-sensitive normal tissue from the radiation field in operation and then the application of a single high-dose precision irradiation to the residual tumor or tumor bed. IORT has great application potential in the control of local recurrence of malignant tumors. This paper thus aims to review the current status and prospects of IORT's application in malignant glioma treatment.
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Affiliation(s)
- Xiaoqin Ji
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Wei Ding
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Jiasheng Wang
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Bin Zhou
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Yikun Li
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Wanrong Jiang
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Hao Pan
- Department of Neurosurgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Jun Gu
- Department of General Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Xiangdong Sun
- Department of Radiation Oncology, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
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2
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Bromberger L, Heise B, Felbermayer K, Leiss-Holzinger E, Ilicic K, Schmid TE, Bergmayr A, Etzelstorfer T, Geinitz H. Radiation-induced alterations in multi-layered, in-vitro skin models detected by optical coherence tomography and histological methods. PLoS One 2023; 18:e0281662. [PMID: 36862637 PMCID: PMC9980765 DOI: 10.1371/journal.pone.0281662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 01/28/2023] [Indexed: 03/03/2023] Open
Abstract
BACKGROUND Inflammatory skin reactions and skin alterations are still a potential side effect in radiation therapy (RT), which also need attention for patients' health care. METHOD In a pre-clinical study we consider alterations in irradiated in-vitro skin models of epidermal and dermal layers. Typical dose regimes in radiation therapy are applied for irradiation. For non-invasive imaging and characterization optical coherence tomography (OCT) is used. Histological staining method is additionally applied for comparison and discussion. RESULTS Structural features, such as keratinization, modifications in epidermal cell layer thickness and disorder in the layering-as indications for reactions to ionizing radiation and aging-could be observed by means of OCT and confirmed by histology. We were able to recognize known RT induced changes such as hyper-keratosis, acantholysis, and epidermal hyperplasia as well as disruption and/or demarcation of the dermo-epidermal junction. CONCLUSION The results may pave the way for OCT to be considered as a possible adjunctive tool to detect and monitor early skin inflammation and side effects of radiotherapy, thus supporting patient healthcare in the future.
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Affiliation(s)
- Luisa Bromberger
- Department of Radiation Oncology, Ordensklinikum Linz Barmherzige Schwestern (BHS), Linz, Austria
| | - Bettina Heise
- Institute for Mathematical Methods in Medicine and Data Based Modelling, Johannes Kepler University (JKU), Linz, Austria
- Research Center for Non-Destructive Testing (RECENDT)-GmbH, Linz, Austria
- * E-mail:
| | | | | | - Katarina Ilicic
- Department of Radiation Oncology, Klinikum rechts der Isar (MRI), TUM München, München, Germany
| | - Thomas Ernst Schmid
- Department of Radiation Oncology, Klinikum rechts der Isar (MRI), TUM München, München, Germany
| | - Alexandra Bergmayr
- Department of Pathology, Ordensklinikum Linz Barmherzige Schwestern (BHS), Linz, Austria
| | - Tanja Etzelstorfer
- Department of Radiation Oncology, Ordensklinikum Linz Barmherzige Schwestern (BHS), Linz, Austria
| | - Hans Geinitz
- Department of Radiation Oncology, Ordensklinikum Linz Barmherzige Schwestern (BHS), Linz, Austria
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3
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Kaeppler JR, Chen J, Buono M, Vermeer J, Kannan P, Cheng W, Voukantsis D, Thompson JM, Hill MA, Allen D, Gomes A, Kersemans V, Kinchesh P, Smart S, Buffa F, Nerlov C, Muschel RJ, Markelc B. Endothelial cell death after ionizing radiation does not impair vascular structure in mouse tumor models. EMBO Rep 2022; 23:e53221. [PMID: 35848459 PMCID: PMC9442312 DOI: 10.15252/embr.202153221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/15/2022] [Accepted: 06/27/2022] [Indexed: 12/24/2022] Open
Abstract
The effect of radiation therapy on tumor vasculature has long been a subject of debate. Increased oxygenation and perfusion have been documented during radiation therapy. Conversely, apoptosis of endothelial cells in irradiated tumors has been proposed as a major contributor to tumor control. To examine these contradictions, we use multiphoton microscopy in two murine tumor models: MC38, a highly vascularized, and B16F10, a moderately vascularized model, grown in transgenic mice with tdTomato-labeled endothelium before and after a single (15 Gy) or fractionated (5 × 3 Gy) dose of radiation. Unexpectedly, even these high doses lead to little structural change of the perfused vasculature. Conversely, non-perfused vessels and blind ends are substantially impaired after radiation accompanied by apoptosis and reduced proliferation of their endothelium. RNAseq analysis of tumor endothelial cells confirms the modification of gene expression in apoptotic and cell cycle regulation pathways after irradiation. Therefore, we conclude that apoptosis of tumor endothelial cells after radiation does not impair vascular structure.
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Affiliation(s)
- Jakob R Kaeppler
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Jianzhou Chen
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Mario Buono
- MRC Molecular Hematology Unit, MRC Weatherall Institute of Molecular Medicine, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Jenny Vermeer
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Pavitra Kannan
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Wei‐Chen Cheng
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Dimitrios Voukantsis
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - James M Thompson
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Mark A Hill
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Danny Allen
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Ana Gomes
- In Vivo ImagingThe Francis Crick InstituteLondonUK
| | - Veerle Kersemans
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Paul Kinchesh
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Sean Smart
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Francesca Buffa
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Claus Nerlov
- MRC Molecular Hematology Unit, MRC Weatherall Institute of Molecular Medicine, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Ruth J Muschel
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Bostjan Markelc
- Cancer Research UK and MRC Oxford Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
- Present address:
Department of Experimental OncologyInstitute of Oncology LjubljanaLjubljanaSlovenia
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4
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Orlova A, Pavlova K, Kurnikov A, Maslennikova A, Myagcheva M, Zakharov E, Skamnitskiy D, Perekatova V, Khilov A, Kovalchuk A, Moiseev A, Turchin I, Razansky D, Subochev P. Noninvasive optoacoustic microangiography reveals dose and size dependency of radiation-induced deep tumor vasculature remodeling. Neoplasia 2022; 26:100778. [PMID: 35220045 PMCID: PMC8889238 DOI: 10.1016/j.neo.2022.100778] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/04/2022] [Accepted: 02/11/2022] [Indexed: 01/07/2023]
Abstract
Tumor microvascular responses may provide a sensitive readout indicative of radiation therapy efficacy, its time course and dose dependencies. However, direct high-resolution observation and longitudinal monitoring of large-scale microvascular remodeling in deep tissues remained challenging with the conventional microscopy approaches. We report on a non-invasive longitudinal study of morphological and functional neovascular responses by means of scanning optoacoustic (ОА) microangiography. In vivo imaging of CT26 tumor response to a single irradiation at varying dose (6, 12, and 18 Gy) has been performed over ten days following treatment. Tumor oxygenation levels were further estimated using diffuse optical spectroscopy (DOS) with a contact fiber probe. OA revealed the formation of extended vascular structures on the whole tumor scale during its proliferation, whereas only short fragmented vascular regions were identified following irradiation. On the first day post treatment, a decrease in the density of small (capillary-sized) and medium-sized vessels was revealed, accompanied by an increase in their fragmentation. Larger vessels exhibited an increase in their density accompanied by a decline in the number of vascular segments. Short-lasting response has been observed after 6 and 12 Gy irradiations, whereas 18 Gy treatment resulted in prolonged responses, up to the tenth day after irradiation. DOS measurements further revealed a delayed increase of tumor oxygenation levels for 18 Gy irradiations, commencing on the sixth day post treatment. The ameliorated oxygenation is attributed to diminished oxygen consumption by inhibited tumor cells but not to the elevation of oxygen supply. This work is the first to demonstrate the differential (size-dependent) nature of vascular responses to radiation treatments at varying doses in vivo. The OA approach thus facilitates the study of radiation-induced vascular changes in an unperturbed in vivo environment while enabling deep tissue high-resolution observations at the whole tumor scale.
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Abstract
Noninvasive optical imaging with deep tissue penetration depth and high spatiotemporal resolution is important to longitudinally studying the biology at the single-cell level in live mammals, but has been challenging due to light scattering. Here, we developed near-infrared II (NIR-II) (1,000 to 1,700 nm) structured-illumination light-sheet microscopy (NIR-II SIM) with ultralong excitation and emission wavelengths up to ∼1,540 and ∼1,700 nm, respectively, suppressing light scattering to afford large volumetric three-dimensional (3D) imaging of tissues with deep-axial penetration depths. Integrating structured illumination into NIR-II light-sheet microscopy further diminished background and improved spatial resolution by approximately twofold. In vivo oblique NIR-II SIM was performed noninvasively for 3D volumetric multiplexed molecular imaging of the CT26 tumor microenvironment in mice, longitudinally mapping out CD4, CD8, and OX40 at the single-cell level in response to immunotherapy by cytosine-phosphate-guanine (CpG), a Toll-like receptor 9 (TLR-9) agonist combined with OX40 antibody treatment. NIR-II SIM affords an additional tool for noninvasive volumetric molecular imaging of immune cells in live mammals.
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Dhaliwal A, Zheng G. Improving accessibility of EPR-insensitive tumor phenotypes using EPR-adaptive strategies: Designing a new perspective in nanomedicine delivery. Theranostics 2019; 9:8091-8108. [PMID: 31754383 PMCID: PMC6857058 DOI: 10.7150/thno.37204] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 07/15/2019] [Indexed: 12/12/2022] Open
Abstract
The enhanced permeability and retention (EPR) effect has underlain the predominant nanomedicine design philosophy for the past three decades. However, growing evidence suggests that it is over-represented in preclinical models, and agents designed solely using its principle of passive accumulation can only be applied to a narrow subset of clinical tumors. For this reason, strategies that can improve upon the EPR effect to facilitate nanomedicine delivery to otherwise non-responsive tumors are required for broad clinical translation. EPR-adaptive nanomedicine delivery comprises a class of chemical and physical techniques that modify tumor accessibility in an effort to increase agent delivery and therapeutic effect. In the present review, we overview the primary benefits and limitations of radiation, ultrasound, hyperthermia, and photodynamic therapy as physical strategies for EPR-adaptive delivery to EPR-insensitive tumor phenotypes, and we reflect upon changes in the preclinical research pathway that should be implemented in order to optimally validate and develop these delivery strategies.
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7
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Integrating Small Animal Irradiators withFunctional Imaging for Advanced Preclinical Radiotherapy Research. Cancers (Basel) 2019; 11:cancers11020170. [PMID: 30717307 PMCID: PMC6406472 DOI: 10.3390/cancers11020170] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/23/2019] [Accepted: 01/29/2019] [Indexed: 12/16/2022] Open
Abstract
Translational research aims to provide direct support for advancing novel treatment approaches in oncology towards improving patient outcomes. Preclinical studies have a central role in this process and the ability to accurately model biological and physical aspects of the clinical scenario in radiation oncology is critical to translational success. The use of small animal irradiators with disease relevant mouse models and advanced in vivo imaging approaches offers unique possibilities to interrogate the radiotherapy response of tumors and normal tissues with high potential to translate to improvements in clinical outcomes. The present review highlights the current technology and applications of small animal irradiators, and explores how these can be combined with molecular and functional imaging in advanced preclinical radiotherapy research.
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8
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Emerging Functional Imaging Biomarkers of Tumour Responses to Radiotherapy. Cancers (Basel) 2019; 11:cancers11020131. [PMID: 30678055 PMCID: PMC6407112 DOI: 10.3390/cancers11020131] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/11/2019] [Accepted: 01/13/2019] [Indexed: 12/11/2022] Open
Abstract
Tumour responses to radiotherapy are currently primarily assessed by changes in size. Imaging permits non-invasive, whole-body assessment of tumour burden and guides treatment options for most tumours. However, in most tumours, changes in size are slow to manifest and can sometimes be difficult to interpret or misleading, potentially leading to prolonged durations of ineffective treatment and delays in changing therapy. Functional imaging techniques that monitor biological processes have the potential to detect tumour responses to treatment earlier and refine treatment options based on tumour biology rather than solely on size and staging. By considering the biological effects of radiotherapy, this review focusses on emerging functional imaging techniques with the potential to augment morphological imaging and serve as biomarkers of early response to radiotherapy.
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9
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Savarin M, Prevc A, Rzek M, Bosnjak M, Vojvodic I, Cemazar M, Jarm T, Sersa G. Intravital Monitoring of Vasculature After Targeted Gene Therapy Alone or Combined With Tumor Irradiation. Technol Cancer Res Treat 2018; 17:1533033818784208. [PMID: 29969947 PMCID: PMC6048615 DOI: 10.1177/1533033818784208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Vascular-targeted therapies exhibit radiosensitizing effects by remodeling tumor
vasculature, thus facilitating the increased oxygenation of the remaining tumor tissue. To
examine these phenomena, the effects of antiendoglin gene therapy alone and in combination
with irradiation were monitored for 5 consecutive days on a murine mammary adenocarcinoma
(TS/A) tumor model growing in a dorsal window chamber. The vascularization of the tumors
was assessed by the determination of the tumor vascular area and by measurement of tumor
perfusion by using laser Doppler flowmetry to provide insight into intratumoral gene
electrotransfer effects. The changes in the vascular area after this specific therapy
correlated with laser Doppler measurements, indicating that either of the methods can be
used to demonstrate the induced changes in the vascularization and perfusion of tumors.
Gene electrotransfer with an endothelial-specific promoter resulted in a vascular-targeted
effect on tumor vasculature within the first 24 hours and did not restore within 5 days.
The combination with the irradiation did not result in a more pronounced vascular effect,
and irradiation alone only abrogated the formation of new vessels and prevented an
increase in the tumor perfusion over time. The results indicate that tumors grown in a
dorsal window chamber facilitate intravital measurements of the vascularization of tumors
and blood perfusion, enabling the monitoring of the antiangiogenic or vascular disruptive
effects of different therapies.
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Affiliation(s)
- Monika Savarin
- 1 Department of Experimental Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia
| | - Ajda Prevc
- 1 Department of Experimental Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia
| | - Matic Rzek
- 2 Department of Biomedical Engineering, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Masa Bosnjak
- 1 Department of Experimental Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia
| | - Ilija Vojvodic
- 3 Division of Radiotherapy, Institute of Oncology Ljubljana, Ljubljana, Slovenia
| | - Maja Cemazar
- 1 Department of Experimental Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia.,4 Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Tomaz Jarm
- 2 Department of Biomedical Engineering, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Gregor Sersa
- 1 Department of Experimental Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia.,5 Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
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Khosravi N, Maeda A, DaCosta RS, Davies JE. Nanosurfaces modulate the mechanism of peri-implant endosseous healing by regulating neovascular morphogenesis. Commun Biol 2018; 1:72. [PMID: 30271953 PMCID: PMC6123776 DOI: 10.1038/s42003-018-0074-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/10/2018] [Indexed: 02/06/2023] Open
Abstract
Nanosurfaces have improved clinical osseointegration by increasing bone/implant contact. Neovascularization is considered an essential prerequisite to osteogenesis, but no previous reports to our knowledge have examined the effect of surface topography on the spatio-temporal pattern of neovascularization during peri-implant healing. We have developed a cranial window model to study peri-implant healing intravitally over clinically relevant time scales as a function of implant topography. Quantitative intravital confocal imaging reveals that changing the topography (but not chemical composition) of an implant profoundly affects the pattern of peri-implant neovascularization. New vessels develop proximal to the implant and the vascular network matures sooner in the presence of an implant nanosurface. Accelerated angiogenesis can lead to earlier osseointegration through the delivery of osteogenic precursors to, and direct formation of bone on, the implant surface. This study highlights a critical aspect of peri-implant healing, but also informs the biological rationale for the surface design of putative endosseous implant materials.
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Affiliation(s)
- Niloufar Khosravi
- Institute for Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, M5G 1G6, Canada
- Faculty of Dentistry, University of Toronto, Toronto, ON, M5G 1G6, Canada
- Princess Margaret Cancer Center, University Health Network, Toronto, ON, M5G 1L7, Canada
| | - Azusa Maeda
- Princess Margaret Cancer Center, University Health Network, Toronto, ON, M5G 1L7, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, M5G 1L7, Canada
| | - Ralph S DaCosta
- Princess Margaret Cancer Center, University Health Network, Toronto, ON, M5G 1L7, Canada.
- Department of Medical Biophysics, University of Toronto, Toronto, ON, M5G 1L7, Canada.
- Techna Institute, University Health Network, Toronto, ON, M5G 1L5, Canada.
| | - John E Davies
- Institute for Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, M5G 1G6, Canada.
- Faculty of Dentistry, University of Toronto, Toronto, ON, M5G 1G6, Canada.
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11
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Meganck JA, Liu B. Dosimetry in Micro-computed Tomography: a Review of the Measurement Methods, Impacts, and Characterization of the Quantum GX Imaging System. Mol Imaging Biol 2018; 19:499-511. [PMID: 27957647 PMCID: PMC5498628 DOI: 10.1007/s11307-016-1026-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Purpose X-ray micro-computed tomography (μCT) is a widely used imaging modality in preclinical research with applications in many areas including orthopedics, pulmonology, oncology, cardiology, and infectious disease. X-rays are a form of ionizing radiation and, therefore, can potentially induce damage and cause detrimental effects. Previous reviews have touched on these effects but have not comprehensively covered the possible implications on study results. Furthermore, interpreting data across these studies is difficult because there is no widely accepted dose characterization methodology for preclinical μCT. The purpose of this paper is to ensure in vivo μCT studies can be properly designed and the data can be appropriately interpreted. Procedures Studies from the scientific literature that investigate the biological effects of radiation doses relevant to μCT were reviewed. The different dose measurement methodologies used in the peer-reviewed literature were also reviewed. The CT dose index 100 (CTDI100) was then measured on the Quantum GX μCT instrument. A low contrast phantom, a hydroxyapatite phantom, and a mouse were also imaged to provide examples of how the dose can affect image quality. Results Data in the scientific literature indicate that scenarios exist where radiation doses used in μCT imaging are high enough to potentially bias experimental results. The significance of this effect may relate to the study outcome and tissue being imaged. CTDI100 is a reasonable metric to use for dose characterization in μCT. Dose rates in the Quantum GX vary based on the amount of material in the beam path and are a function of X-ray tube voltage. The CTDI100 in air for a Quantum GX can be as low as 5.1 mGy for a 50 kVp scan and 9.9 mGy for a 90 kVp scan. This dose is low enough to visualize bone both in a mouse image and in a hydroxyapatite phantom, but applications requiring higher resolution in a mouse or less noise in a low-contrast phantom benefit from longer scan times with increased dose. Conclusions Dose management should be considered when designing μCT studies. Dose rates in the Quantum GX are compatible with longitudinal μCT imaging.
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Affiliation(s)
- Jeffrey A Meganck
- Research and Development, Life Sciences Technology, PerkinElmer, 68 Elm Street, Hopkinton, MA, 01748, USA.
| | - Bob Liu
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
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12
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Jelvehgaran P, de Bruin DM, Salguero FJ, Borst GR, Song JY, van Leeuwen TG, de Boer JF, Alderliesten T, van Herk M. Feasibility of using optical coherence tomography to detect acute radiation-induced esophageal damage in small animal models. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-12. [PMID: 29651825 DOI: 10.1117/1.jbo.23.4.046004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 03/26/2018] [Indexed: 05/25/2023]
Abstract
Lung cancer survival is poor, and radiation therapy patients often suffer serious treatment side effects. The esophagus is particularly sensitive leading to acute radiation-induced esophageal damage (ARIED). We investigated the feasibility of optical coherence tomography (OCT) for minimally invasive imaging of the esophagus with high resolution (10 μm) to detect ARIED in mice. Thirty mice underwent cone-beam computed tomography imaging for initial setup assessment and dose planning followed by a single-dose delivery of 4.0, 10.0, 16.0, and 20.0 Gy on 5.0-mm spots, spaced 10.0 mm apart in the esophagus. They were repeatedly imaged using OCT up to three months postirradiation. We compared OCT findings with histopathology obtained three months postirradiation qualitatively and quantitatively using the contrast-to-background-noise ratio (CNR). Histopathology mostly showed inflammatory infiltration and edema at higher doses; OCT findings were in agreement with most of the histopathological reports. We were able to identify the ARIED on OCT as a change in tissue scattering and layer thickness. Our statistical analysis showed significant difference between the CNR values of healthy tissue, edema, and inflammatory infiltration. Overall, the average CNR for inflammatory infiltration and edema damages was 1.6-fold higher and 1.6-fold lower than for the healthy esophageal wall, respectively. Our results showed the potential role of OCT to detect and monitor the ARIED in mice, which may translate to humans.
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Affiliation(s)
- Pouya Jelvehgaran
- Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam, The Netherlands
- Academic Medical Center, Department of Radiation Oncology, Amsterdam, The Netherlands
- Institute for Laser Life and Biophotonics Amsterdam, Department of Physics and Astronomy, Amsterdam, The Netherlands
| | - Daniel Martijn de Bruin
- Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam, The Netherlands
- Academic Medical Center, Department of Urology, Amsterdam, The Netherlands
| | - F Javier Salguero
- The Netherlands Cancer Institute, Department of Radiation Oncology, Amsterdam, The Netherlands
| | - Gerben Roelof Borst
- The Netherlands Cancer Institute, Department of Radiation Oncology, Amsterdam, The Netherlands
| | - Ji-Ying Song
- The Netherlands Cancer Institute, Department of Experimental Animal Pathology, Amsterdam, The Netherlands
| | - Ton G van Leeuwen
- Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam, The Netherlands
| | - Johannes F de Boer
- Institute for Laser Life and Biophotonics Amsterdam, Department of Physics and Astronomy, Amsterdam, The Netherlands
| | - Tanja Alderliesten
- Academic Medical Center, Department of Radiation Oncology, Amsterdam, The Netherlands
| | - Marcel van Herk
- Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam, The Netherlands
- University of Manchester, Institute of Cancer Sciences, Manchester, United Kingdom
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13
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Kirsch DG, Diehn M, Kesarwala AH, Maity A, Morgan MA, Schwarz JK, Bristow R, Demaria S, Eke I, Griffin RJ, Haas-Kogan D, Higgins GS, Kimmelman AC, Kimple RJ, Lombaert IM, Ma L, Marples B, Pajonk F, Park CC, Schaue D, Tran PT, Willers H, Wouters BG, Bernhard EJ. The Future of Radiobiology. J Natl Cancer Inst 2018; 110:329-340. [PMID: 29126306 PMCID: PMC5928778 DOI: 10.1093/jnci/djx231] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/19/2017] [Accepted: 10/06/2017] [Indexed: 12/23/2022] Open
Abstract
Innovation and progress in radiation oncology depend on discovery and insights realized through research in radiation biology. Radiobiology research has led to fundamental scientific insights, from the discovery of stem/progenitor cells to the definition of signal transduction pathways activated by ionizing radiation that are now recognized as integral to the DNA damage response (DDR). Radiobiological discoveries are guiding clinical trials that test radiation therapy combined with inhibitors of the DDR kinases DNA-dependent protein kinase (DNA-PK), ataxia telangiectasia mutated (ATM), ataxia telangiectasia related (ATR), and immune or cell cycle checkpoint inhibitors. To maintain scientific and clinical relevance, the field of radiation biology must overcome challenges in research workforce, training, and funding. The National Cancer Institute convened a workshop to discuss the role of radiobiology research and radiation biologists in the future scientific enterprise. Here, we review the discussions of current radiation oncology research approaches and areas of scientific focus considered important for rapid progress in radiation sciences and the continued contribution of radiobiology to radiation oncology and the broader biomedical research community.
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Affiliation(s)
- David G Kirsch
- Department of Radiation Oncology and Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Max Diehn
- Department of Radiation Oncology, Stanford Cancer Institute, and Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA
| | | | - Amit Maity
- Department of Radiation Oncology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Meredith A Morgan
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI
| | - Julie K Schwarz
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO
| | - Robert Bristow
- Department of Radiation Oncology, Princess Margaret Cancer Center, Toronto, ON, Canada
| | - Sandra Demaria
- Department of Radiation Oncology and Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY
| | - Iris Eke
- Radiation Oncology Branch, National Institutes of Health, Bethesda, MD
| | - Robert J Griffin
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Daphne Haas-Kogan
- Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, Brigham and Women's Hospital, Boston Children's Hospital, Boston, MA
| | - Geoff S Higgins
- Department of Oncology, University of Oxford, Oxford, Oxfordshire, UK
| | - Alec C Kimmelman
- Perlmutter Cancer Center and Department of Radiation Oncology, New York University Langone Medical Center, New York, NY
| | - Randall J Kimple
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Isabelle M Lombaert
- Department of Biologic and Materials Sciences, Biointerfaces Institute, School of Dentistry, University of Michigan, Ann Arbor, MI
| | - Li Ma
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Brian Marples
- Department of Radiation Oncology, University of Miami, Miami, FL
| | - Frank Pajonk
- Department of Radiation Oncology, University of California, Los Angeles, CA
| | - Catherine C Park
- David Geffen School of Medicine, University of California, Los Angeles, CA
- Department of Radiation Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA
| | - Dörthe Schaue
- Division of Molecular and Cellular Oncology, University of California, Los Angeles, CA
| | - Phuoc T. Tran
- Department of Radiation Oncology and Molecular Radiation Sciences, Oncology and Urology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Henning Willers
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Brad G. Wouters
- Department of Radiation Oncology (RB), Princess Margaret Cancer Center
| | - Eric J Bernhard
- Radiation Research Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institutes of Health, Bethesda, MD
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14
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Demidov V, Maeda A, Sugita M, Madge V, Sadanand S, Flueraru C, Vitkin IA. Preclinical longitudinal imaging of tumor microvascular radiobiological response with functional optical coherence tomography. Sci Rep 2018; 8:38. [PMID: 29311686 PMCID: PMC5758802 DOI: 10.1038/s41598-017-18635-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/14/2017] [Indexed: 01/11/2023] Open
Abstract
Radiation therapy (RT) is widely used for cancer treatment, alone or in combination with other therapies. Recent RT advances have revived interest in delivering higher dose in fewer fractions, which may invoke both cellular and microvascular damage mechanisms. Microvasculature may thus be a potentially sensitive functional biomarker of RT early response, especially for such emerging RT treatments. However it is difficult to measure directly and non-invasively, and its time course, dose dependencies, and overall importance in tumor control are unclear. We use functional optical coherence tomography for quantitative longitudinal in vivo imaging in preclinical models of human tumor xenografts subjected to 10, 20 and 30 Gy doses, furnishing a detailed assessment of vascular remodeling following RT. Immediate (minutes to tens of minutes) and early (days to weeks) RT responses of microvascular supply, as well as tumor volume and fluorescence intensity, were quantified and demonstrated robust and complex temporal dose-dependent behaviors. The findings were compared to theoretical models proposed in the literature.
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Affiliation(s)
- Valentin Demidov
- University of Toronto, Department of Medical Biophysics, Toronto, Canada.
| | - Azusa Maeda
- University of Toronto, Department of Medical Biophysics, Toronto, Canada
| | - Mitsuro Sugita
- University Health Network, Princess Margaret Cancer Centre, Toronto, Canada
| | - Victoria Madge
- Carleton University, Department of Systems and Computer Engineering, Ottawa, Canada
| | | | - Costel Flueraru
- National Research Council Canada, Information Communication Technology, Ottawa, Canada
| | - I Alex Vitkin
- University of Toronto, Department of Medical Biophysics, Toronto, Canada.,University Health Network, Princess Margaret Cancer Centre, Toronto, Canada.,University of Toronto, Department of Radiation Oncology, Toronto, Canada
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15
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Kasoji SK, Rivera JN, Gessner RC, Chang SX, Dayton PA. Early Assessment of Tumor Response to Radiation Therapy using High-Resolution Quantitative Microvascular Ultrasound Imaging. Am J Cancer Res 2018; 8:156-168. [PMID: 29290799 PMCID: PMC5743466 DOI: 10.7150/thno.19703] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 08/22/2017] [Indexed: 12/18/2022] Open
Abstract
Measuring changes in tumor volume using anatomical imaging weeks to months post radiation therapy (RT) is currently the clinical standard for indicating treatment response to RT. For patients whose tumors do not respond successfully to treatment, this approach is suboptimal as timely modification of the treatment approach may lead to better clinical outcomes. We propose to use tumor microvasculature as a biomarker for early assessment of tumor response to RT. Acoustic angiography is a novel contrast ultrasound imaging technique that enables high-resolution microvascular imaging and has been shown to detect changes in microvascular structure due to cancer growth. Data suggest that acoustic angiography can detect longitudinal changes in the tumor microvascular environment that correlate with RT response. Methods: Three cohorts of Fisher 344 rats were implanted with rat fibrosarcoma tumors and were treated with a single fraction of RT at three dose levels (15 Gy, 20 Gy, and 25 Gy) at a dose rate of 300 MU/min. A simple treatment condition was chosen for testing the feasibility of our imaging technique. All tumors were longitudinally imaged immediately prior to and after treatment and then every 3 days after treatment for a total of 30 days. Both acoustic angiography (using in-house produced microbubble contrast agents) and standard b-mode imaging was performed at each imaging time point using a pre-clinical Vevo770 scanner and a custom modified dual-frequency transducer. Results: Results show that all treated tumors in each dose group initially responded to treatment between days 3-15 as indicated by decreased tumor growth accompanied with decreased vascular density. Untreated tumors continued to increase in both volume and vascular density until they reached the maximum allowable size of 2 cm in diameter. Tumors that displayed complete control (no tumor recurrence) continued to decrease in size and vascular density, while tumors that progressed after the initial response presented an increase in tumor volume and volumetric vascular density. The increase in tumor volumetric vascular density in recurring tumors can be detected 10.25 ± 1.5 days, 6 ± 0 days, and 4 ± 1.4 days earlier than the measurable increase in tumor volume in the 15, 20, and 25 Gy dose groups, respectively. A dose-dependent growth rate for tumor recurrence was also observed. Conclusions: In this feasibility study we have demonstrated the ability of acoustic angiography to detect longitudinal changes in vascular density, which was shown to be a potential biomarker for tumor response to RT.
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16
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Herskind C, Ma L, Liu Q, Zhang B, Schneider F, Veldwijk MR, Wenz F. Biology of high single doses of IORT: RBE, 5 R's, and other biological aspects. Radiat Oncol 2017; 12:24. [PMID: 28107823 PMCID: PMC5251326 DOI: 10.1186/s13014-016-0750-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 12/21/2016] [Indexed: 01/14/2023] Open
Abstract
Intraoperative radiotherapy differs from conventional, fractionated radiotherapy in several aspects that may influence its biological effect. The radiation quality influences the relative biologic effectiveness (RBE), and the role of the five R’s of radiotherapy (reassortment, repair, reoxygenation, repopulation, radiosensitivity) is different. Furthermore, putative special biological effects and the small volume receiving a high single dose may be important. The present review focuses on RBE, repair, and repopulation, and gives an overview of the other factors that potentially contribute to the efficacy. The increased RBE should be taken into account for low-energy X-rays while evidence of RBE < 1 for high-energy electrons at higher doses is presented. Various evidence supports a hypothesis that saturation of the primary DNA double-strand break (DSB) repair mechanisms leads to increasing use of an error-prone backup repair system leading to genomic instability that may contribute to inactivate tumour cells at high single doses. Furthermore, the elimination of repopulation of residual tumour cells in the tumour bed implies that some patients are likely to have very few residual tumour cells which may be cured even by low doses to the tumour bed. The highly localised dose distribution of IORT has the potential to inactivate tumour cells while sparing normal tissue by minimising the volume exposed to high doses. Whether special effects of high single doses also contribute to the efficacy will require further experimental and clinical studies.
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Affiliation(s)
- Carsten Herskind
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
| | - Lin Ma
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.,Present Address: Department of Radiation Oncology, University of California, San Francisco, CA, USA
| | - Qi Liu
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.,Present Address: Department of Radiation Oncology, University of California, San Francisco, CA, USA
| | - Bo Zhang
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.,Present Address: Department of Oncology at No. 2 Hospital Anhui Medical University, and School of Life Sciences, Anhui Medical University, Hefei, Anhui, China
| | - Frank Schneider
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Marlon R Veldwijk
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Frederik Wenz
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
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17
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Melsens E, Verberckmoes B, Rosseel N, Vanhove C, Descamps B, Pattyn P, Ceelen W. The VEGFR Inhibitor Cediranib Improves the Efficacy of Fractionated Radiotherapy in a Colorectal Cancer Xenograft Model. Eur Surg Res 2016; 58:95-108. [PMID: 28002822 DOI: 10.1159/000452741] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 10/19/2016] [Indexed: 12/16/2022]
Abstract
BACKGROUND/PURPOSE Radiotherapy (RT) increases local tumor control in locally advanced rectal cancer, but complete histological response is seen in only a minority of cases. Antiangiogenic therapy has been proposed to improve RT efficacy by "normalizing" the tumor microvasculature. Here, we examined whether cediranib, a pan-vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor, improves microvascular function and tumor control in combination with RT in a mouse colorectal cancer (CRC) model. METHODS CRC xenografts (HT29) were grown subcutaneously in mice. Animals were treated for 5 consecutive days with vehicle, RT (1.8 Gy daily), cediranib (6 mg/kg po), or combined therapy (cediranib 2 h prior to radiation). Tumor volume was measured with calipers. Vascular changes were analyzed by dynamic contrast-enhanced MRI, oxygenation and interstitial fluid pressure probes and histology. To investigate vascular changes more in detail, a second set of mice were fitted with titanium dorsal skinfold window chambers, wherein a HT29 tumor cell suspension was injected. In vivo fluorescence microscopy was performed before and after treatment (same treatment protocol). RESULTS In vivo microscopy analyses showed that VEGFR inhibition with cediranib led to a "normalization" of the vessel wall, with decreased microvessel permeability (p < 0.0001) and tortuosity (p < 0.01), and a trend to decreased vessel diameters. This seemed to lead to lower tumor hypoxia rates in the cediranib and combination groups compared to the control and RT groups. This led to an increased tumor control in the combination group compared to controls or monotherapy (p < 0.0001). CONCLUSIONS The combination of RT with cediranib enhances tumor control in a CRC xenograft mouse model. Microvascular analyses suggest that cediranib leads to vascular normalization and improved oxygenation.
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Affiliation(s)
- Elodie Melsens
- Laboratory of Experimental Surgery, Department of Surgery, Ghent University Hospital, Ghent, Belgium
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18
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Ford E, Emery R, Huff D, Narayanan M, Schwartz J, Cao N, Meyer J, Rengan R, Zeng J, Sandison G, Laramore G, Mayr N. An image-guided precision proton radiation platform for preclinicalin vivoresearch. Phys Med Biol 2016; 62:43-58. [DOI: 10.1088/1361-6560/62/1/43] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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19
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Maeda A, Chen Y, Bu J, Mujcic H, Wouters BG, DaCosta RS. In Vivo Imaging Reveals Significant Tumor Vascular Dysfunction and Increased Tumor Hypoxia-Inducible Factor-1α Expression Induced by High Single-Dose Irradiation in a Pancreatic Tumor Model. Int J Radiat Oncol Biol Phys 2016; 97:184-194. [PMID: 27816364 DOI: 10.1016/j.ijrobp.2016.09.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 08/31/2016] [Accepted: 09/06/2016] [Indexed: 02/07/2023]
Abstract
PURPOSE To investigate the effect of high-dose irradiation on pancreatic tumor vasculature and microenvironment using in vivo imaging techniques. METHODS AND MATERIALS A BxPC3 pancreatic tumor xenograft was established in a dorsal skinfold window chamber model and a subcutaneous hind leg model. Tumors were irradiated with a single dose of 4, 12, or 24 Gy. The dorsal skinfold window chamber model was used to assess tumor response, vascular function and permeability, platelet and leukocyte adhesion to the vascular endothelium, and tumor hypoxia for up to 14 days after 24-Gy irradiation. The hind leg model was used to monitor tumor size, hypoxia, and vascularity for up to 65 days after 24-Gy irradiation. Tumors were assessed histologically to validate in vivo observations. RESULTS In vivo fluorescence imaging revealed temporary vascular dysfunction in tumors irradiated with a single dose of 4 to 24 Gy, but most significantly with a single dose of 24 Gy. Vascular functional recovery was observed by 14 days after irradiation in a dose-dependent manner. Furthermore, irradiation with 24 Gy caused platelet and leukocyte adhesion to the vascular endothelium within hours to days after irradiation. Vascular permeability was significantly higher in irradiated tumors compared with nonirradiated controls 14 days after irradiation. This observation corresponded with increased expression of hypoxia-inducible factor-1α in irradiated tumors. In the hind leg model, irradiation with a single dose of 24 Gy led to tumor growth delay, followed by tumor regrowth. CONCLUSIONS Irradiation of the BxPC3 tumors with a single dose of 24 Gy caused transient vascular dysfunction and increased expression of hypoxia-inducible factor-1α. Such biological changes may impact tumor response to high single-dose and hypofractionated irradiation, and further investigations are needed to better understand the clinical outcomes of stereotactic body radiation therapy.
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Affiliation(s)
- Azusa Maeda
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Yonghong Chen
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Jiachuan Bu
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Hilda Mujcic
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Bradly G Wouters
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Ralph S DaCosta
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; Techna Institute, University Health Network, Toronto, Ontario, Canada.
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20
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Abstract
Tumours contain multiple different cell populations, including cells derived from the bone marrow as well as cancer-associated fibroblasts and various stromal populations including the vasculature. The microenvironment of the tumour cells plays a significant role in the response of the tumour to radiation treatment. Low levels of oxygen (hypoxia) caused by the poorly organized vasculature in tumours have long been known to affect radiation response; however, other aspects of the microenvironment may also play important roles. This article reviews some of the old literature concerning tumour response to irradiation and relates this to current concepts about the role of the tumour microenvironment in tumour response to radiation treatment. Included in the discussion are the role of cancer stem cells, radiation damage to the vasculature and the potential for radiation to enhance immune activity against tumour cells. Radiation treatment can cause a significant influx of bone marrow-derived cell populations into both normal tissues and tumours. Potential roles of such cells may include enhancing vascular recovery as well as modulating immune reactivity.
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Affiliation(s)
- Richard P Hill
- 1 Ontario Cancer Institute, Princess Margaret Cancer Centre, Toronto, ON, Canada.,2 Departments of Medical Biophysics and Radiation Oncology, University of Toronto, Toronto, ON, Canada
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21
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Assadi H, Demidov V, Karshafian R, Douplik A, Vitkin IA. Microvascular contrast enhancement in optical coherence tomography using microbubbles. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:76014. [PMID: 27533242 DOI: 10.1117/1.jbo.21.7.076014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 07/11/2016] [Indexed: 06/06/2023]
Abstract
Gas microbubbles (MBs) are investigated as intravascular optical coherence tomography (OCT) contrast agents. Agar + intralipid scattering tissue phantoms with two embedded microtubes were fabricated to model vascular blood flow. One was filled with human blood, and the other with a mixture of human blood + MB. Swept-source structural and speckle variance (sv) OCT images, as well as speckle decorrelation times, were evaluated under both no-flow and varying flow conditions. Faster decorrelation times and higher structural and svOCT image contrasts were detected in the presence of MB in all experiments. The effects were largest in the svOCT imaging mode, and uniformly diminished with increasing flow velocity. These findings suggest the feasibility of utilizing MB for tissue hemodynamic investigations and for microvasculature contrast enhancement in OCT angiography.
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Affiliation(s)
- Homa Assadi
- Ryerson University, Department of Physics, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
| | - Valentin Demidov
- University of Toronto, Department of Medical Biophysics, Toronto Medical Discovery Tower, MaRS Centre, 101 College Street, Room 15-701, Toronto, Ontario M5G 1L7, Canada
| | - Raffi Karshafian
- Ryerson University, Department of Physics, 350 Victoria Street, Toronto, Ontario M5B 2K3, CanadacSt. Michael Hospital, Keenan Research Centre of the LKS Knowledge Institute, 209 Victoria Street, Toronto M5B 1W8, Canada
| | - Alexandre Douplik
- Ryerson University, Department of Physics, 350 Victoria Street, Toronto, Ontario M5B 2K3, CanadacSt. Michael Hospital, Keenan Research Centre of the LKS Knowledge Institute, 209 Victoria Street, Toronto M5B 1W8, Canada
| | - I Alex Vitkin
- University of Toronto, Department of Medical Biophysics, Toronto Medical Discovery Tower, MaRS Centre, 101 College Street, Room 15-701, Toronto, Ontario M5G 1L7, CanadadUniversity Health Network, Princess Margaret Cancer Centre, 610 University Avenue, Tor
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22
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Stewart JMP, Ansell S, Lindsay PE, Jaffray DA. Online virtual isocenter based radiation field targeting for high performance small animal microirradiation. Phys Med Biol 2015; 60:9031-46. [PMID: 26540304 DOI: 10.1088/0031-9155/60/23/9031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Advances in precision microirradiators for small animal radiation oncology studies have provided the framework for novel translational radiobiological studies. Such systems target radiation fields at the scale required for small animal investigations, typically through a combination of on-board computed tomography image guidance and fixed, interchangeable collimators. Robust targeting accuracy of these radiation fields remains challenging, particularly at the millimetre scale field sizes achievable by the majority of microirradiators. Consistent and reproducible targeting accuracy is further hindered as collimators are removed and inserted during a typical experimental workflow. This investigation quantified this targeting uncertainty and developed an online method based on a virtual treatment isocenter to actively ensure high performance targeting accuracy for all radiation field sizes. The results indicated that the two-dimensional field placement uncertainty was as high as 1.16 mm at isocenter, with simulations suggesting this error could be reduced to 0.20 mm using the online correction method. End-to-end targeting analysis of a ball bearing target on radiochromic film sections showed an improved targeting accuracy with the three-dimensional vector targeting error across six different collimators reduced from [Formula: see text] mm (mean ± SD) to [Formula: see text] mm for an isotropic imaging voxel size of 0.1 mm.
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Affiliation(s)
- James M P Stewart
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3E2, Canada. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
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23
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Bache ST, Juang T, Belley MD, Koontz BF, Adamovics J, Yoshizumi TT, Kirsch DG, Oldham M. Investigating the accuracy of microstereotactic-body-radiotherapy utilizing anatomically accurate 3D printed rodent-morphic dosimeters. Med Phys 2015; 42:846-55. [PMID: 25652497 DOI: 10.1118/1.4905489] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Sophisticated small animal irradiators, incorporating cone-beam-CT image-guidance, have recently been developed which enable exploration of the efficacy of advanced radiation treatments in the preclinical setting. Microstereotactic-body-radiation-therapy (microSBRT) is one technique of interest, utilizing field sizes in the range of 1-15 mm. Verification of the accuracy of microSBRT treatment delivery is challenging due to the lack of available methods to comprehensively measure dose distributions in representative phantoms with sufficiently high spatial resolution and in 3 dimensions (3D). This work introduces a potential solution in the form of anatomically accurate rodent-morphic 3D dosimeters compatible with ultrahigh resolution (0.3 mm(3)) optical computed tomography (optical-CT) dose read-out. METHODS Rodent-morphic dosimeters were produced by 3D-printing molds of rodent anatomy directly from contours defined on x-ray CT data sets of rats and mice, and using these molds to create tissue-equivalent radiochromic 3D dosimeters from Presage. Anatomically accurate spines were incorporated into some dosimeters, by first 3D printing the spine mold, then forming a high-Z bone equivalent spine insert. This spine insert was then set inside the tissue equivalent body mold. The high-Z spinal insert enabled representative cone-beam CT IGRT targeting. On irradiation, a linear radiochromic change in optical-density occurs in the dosimeter, which is proportional to absorbed dose, and was read out using optical-CT in high-resolution (0.5 mm isotropic voxels). Optical-CT data were converted to absolute dose in two ways: (i) using a calibration curve derived from other Presage dosimeters from the same batch, and (ii) by independent measurement of calibrated dose at a point using a novel detector comprised of a yttrium oxide based nanocrystalline scintillator, with a submillimeter active length. A microSBRT spinal treatment was delivered consisting of a 180° continuous arc at 225 kVp with a 20 × 10 mm field size. Dose response was evaluated using both the Presage/optical-CT 3D dosimetry system described above, and independent verification in select planes using EBT2 radiochromic film placed inside rodent-morphic dosimeters that had been sectioned in half. RESULTS Rodent-morphic 3D dosimeters were successfully produced from Presage radiochromic material by utilizing 3D printed molds of rat CT contours. The dosimeters were found to be compatible with optical-CT dose readout in high-resolution 3D (0.5 mm isotropic voxels) with minimal artifacts or noise. Cone-beam CT image guidance was possible with these dosimeters due to sufficient contrast between high-Z spinal inserts and tissue equivalent Presage material (CNR ∼10 on CBCT images). Dose at isocenter measured with optical-CT was found to agree with nanoscintillator measurement to within 2.8%. Maximum dose in line profiles taken through Presage and film dose slices agreed within 3%, with FWHM measurements through each profile found to agree within 2%. CONCLUSIONS This work demonstrates the feasibility of using 3D printing technology to make anatomically accurate Presage rodent-morphic dosimeters incorporating spinal-mimicking inserts. High quality optical-CT 3D dosimetry is feasible on these dosimeters, despite the irregular surfaces and implanted inserts. The ability to measure dose distributions in anatomically accurate phantoms represents a powerful useful additional verification tool for preclinical microSBRT.
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Affiliation(s)
- Steven T Bache
- Duke University Medical Physics Graduate Program, Durham, North Carolina 27705
| | - Titania Juang
- Duke University Medical Physics Graduate Program, Durham, North Carolina 27705
| | - Matthew D Belley
- Duke University Medical Physics Graduate Program, Durham, North Carolina 27705
| | | | | | | | - David G Kirsch
- Duke University Medical Center, Durham, North Carolina 27710
| | - Mark Oldham
- Duke University Medical Center, Durham, North Carolina 27710
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Maeda A, Kulbatski I, DaCosta RS. Emerging Applications for Optically Enabled Intravital Microscopic Imaging in Radiobiology. Mol Imaging 2015. [DOI: 10.2310/7290.2015.00022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Azusa Maeda
- From the Princess Margaret Cancer Centre, University Health Network, MaRS Centre; Techna Institute for Advancement of Technologies for Health; and Department of Medical Biophysics, University of Toronto, MaRS Centre, Toronto, ON
| | - Iris Kulbatski
- From the Princess Margaret Cancer Centre, University Health Network, MaRS Centre; Techna Institute for Advancement of Technologies for Health; and Department of Medical Biophysics, University of Toronto, MaRS Centre, Toronto, ON
| | - Ralph S. DaCosta
- From the Princess Margaret Cancer Centre, University Health Network, MaRS Centre; Techna Institute for Advancement of Technologies for Health; and Department of Medical Biophysics, University of Toronto, MaRS Centre, Toronto, ON
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25
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Maslennikova A, Kochueva M, Ignatieva N, Vitkin A, Zakharkina O, Kamensky V, Sergeeva E, Kiseleva E, Bagratashvili V. Effects of gamma irradiation on collagen damage and remodeling. Int J Radiat Biol 2015; 91:240-7. [PMID: 25300691 DOI: 10.3109/09553002.2014.969848] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To evaluate the dose-time dependences of structural changes occurring in collagen within 24 hours to three months after gamma-irradiation at doses from 2-40 Gy in vivo. MATERIALS AND METHODS Rat's tail tendon was chosen as in vivo model, with its highly ordered collagen structure allowing the changes to be interpreted unambiguously. Macromolecular level (I) was investigated by differential scanning calorimetry (DSC); fibers and bundles level (II) by laser scanning microscopy (LSM), and bulk tissue microstructural level (III) by cross-polarization optical coherence tomography (CP-OCT). RESULTS For (I), the formation of molecular cross-links and breaks appeared to be a principal mechanism of collagen remodeling, with the cross-links number dependent on radiation dose. Changes on level (II) involved primary, secondary and tertiary bundles splitting in a day and a week after irradiation. Bulk collagen microstructure (III) demonstrated early widening of the interference fringes on CP-OCT images observed to occur in the tendon as result of this splitting. At all three levels, the observed collagen changes demonstrated complete remodeling within ∼ a month following irradiation. CONCLUSION The time course and dose dependencies of the observed collagen changes at different levels of its hierarchy further contribute to elucidating the role of connective tissue in the radiotherapy process.
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Affiliation(s)
- Anna Maslennikova
- Nizhny Novgorod State Medical Academy , Nizhny Novgorod , Russian Federation
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Tillner F, Thute P, Bütof R, Krause M, Enghardt W. Pre-clinical research in small animals using radiotherapy technology – a bidirectional translational approach. Z Med Phys 2014; 24:335-51. [DOI: 10.1016/j.zemedi.2014.07.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 07/18/2014] [Accepted: 07/18/2014] [Indexed: 01/17/2023]
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27
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Dilworth JT, Krueger SA, Wilson GD, Marples B. Preclinical models for translational research should maintain pace with modern clinical practice. Int J Radiat Oncol Biol Phys 2014; 88:540-4. [PMID: 24521673 DOI: 10.1016/j.ijrobp.2013.11.209] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 11/07/2013] [Accepted: 11/08/2013] [Indexed: 01/09/2023]
Affiliation(s)
- Joshua T Dilworth
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan
| | - Sarah A Krueger
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan
| | - George D Wilson
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan
| | - Brian Marples
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan.
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28
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Maeda A, DaCosta RS. Optimization of the dorsal skinfold window chamber model and multi-parametric characterization of tumor-associated vasculature. INTRAVITAL 2014; 3:e27935. [PMID: 28243506 PMCID: PMC5312716 DOI: 10.4161/intv.27935] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 11/21/2022]
Abstract
The dorsal skinfold window chamber (DSWC) model is a unique tool that enables analysis of various aspects of tumor biology and therapeutic response. Although the protocol for the murine DSWC model is standardized, certain tumors fail to grow or require a particular environment to promote growth. Given such limitations, we optimized the DSWC model for a slow-growing tumor that regresses spontaneously in the standard protocol. We further characterized the vascular network in the tumor model compared with that of non-tumor-bearing mice and observed significant differences in multiple parameters related to vascular structure and function.
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Affiliation(s)
- Azusa Maeda
- Ontario Cancer Institute; University Health Network; Toronto, ON Canada; Department of Medical Biophysics; University of Toronto; Toronto, ON Canada
| | - Ralph S DaCosta
- Ontario Cancer Institute; University Health Network; Toronto, ON Canada; Department of Medical Biophysics; University of Toronto; Toronto, ON Canada
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29
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Potiron VA, Abderrahmani R, Clément-Colmou K, Marionneau-Lambot S, Oullier T, Paris F, Supiot S. Improved functionality of the vasculature during conventionally fractionated radiation therapy of prostate cancer. PLoS One 2013; 8:e84076. [PMID: 24391887 PMCID: PMC3877206 DOI: 10.1371/journal.pone.0084076] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 11/20/2013] [Indexed: 11/18/2022] Open
Abstract
Although endothelial cell apoptosis participates in the tumor shrinkage after single high-dose radiotherapy, little is known regarding the vascular response after conventionally fractionated radiation therapy. Therefore, we evaluated hypoxia, perfusion and vascular microenvironment changes in an orthotopic prostate cancer model of conventionally fractionated radiation therapy at clinically relevant doses (2 Gy fractions, 5 fractions/week). First, conventionally fractionated radiation therapy decreased tumor cell proliferation and increased cell death with kinetics comparable to human prostate cancer radiotherapy. Secondly, the injection of Hoechst 33342 or fluorescent-dextrans showed an increased tumor perfusion within 14 days in irradiated tumors, which was correlated with a clear reduction of hypoxia. Improved perfusion and decreased hypoxia were not explained by increased blood vessel density, size or network morphology. However, a tumor vascular maturation defined by perivascular desmin+/SMA+ cells coverage was clearly observed along with an increase in endothelial, zonula occludens (ZO)-1 positive, intercellular junctions. Our results show that, in addition to tumor cell killing, vascular maturation plays an uncovered role in tumor reoxygenation during fractionated radiation therapy.
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Affiliation(s)
- Vincent A. Potiron
- Inserm, UMR892, Nantes, France
- Université de Nantes, Nantes, France
- CNRS, UMR6299, Nantes, France
| | - Rym Abderrahmani
- Inserm, UMR892, Nantes, France
- Université de Nantes, Nantes, France
- CNRS, UMR6299, Nantes, France
| | - Karen Clément-Colmou
- Inserm, UMR892, Nantes, France
- Université de Nantes, Nantes, France
- CNRS, UMR6299, Nantes, France
- Department of Radiation Oncology, Institut de Cancérologie de l’Ouest, Saint-Herblain, France
| | | | | | - François Paris
- Inserm, UMR892, Nantes, France
- Université de Nantes, Nantes, France
- CNRS, UMR6299, Nantes, France
- Department of Radiation Oncology, Institut de Cancérologie de l’Ouest, Saint-Herblain, France
| | - Stéphane Supiot
- Inserm, UMR892, Nantes, France
- Université de Nantes, Nantes, France
- CNRS, UMR6299, Nantes, France
- Department of Radiation Oncology, Institut de Cancérologie de l’Ouest, Saint-Herblain, France
- * E-mail:
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30
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Stewart JMP, Lindsay PE, Jaffray DA. Two-dimensional inverse planning and delivery with a preclinical image guided microirradiator. Med Phys 2013; 40:101709. [DOI: 10.1118/1.4819935] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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31
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Lindenmaier AA, Conroy L, Farhat G, DaCosta RS, Flueraru C, Vitkin IA. Texture analysis of optical coherence tomography speckle for characterizing biological tissues in vivo. OPTICS LETTERS 2013; 38:1280-2. [PMID: 23595458 DOI: 10.1364/ol.38.001280] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
We demonstrate a method for differentiating tissue disease states using the intrinsic texture properties of speckle in optical coherence tomography (OCT) images of normal and tumor tissues obtained in vivo. This approach fits a gamma distribution function to the nonlog-compressed OCT image intensities, thus allowing differentiation of normal and tumor tissues in an ME-180 human cervical cancer mouse xenograft model. Quantitative speckle intensity distribution analysis thus shows promise for identifying tissue pathologies, with potential for early cancer detection in vivo.
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Affiliation(s)
- Andras A Lindenmaier
- Department of Medical Biophysics, University of Toronto, 610 University Ave., Toronto, Ontario M5G 2M9, Canada
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32
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Eslami S, Yang Y, Wong J, Patterson MS, Iordachita I. An Integrated X-Ray/Optical Tomography System for Pre-clinical Radiation Research. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2013; 8668:866830. [PMID: 25745539 DOI: 10.1117/12.2008060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The current Small Animal Radiation Research Platform (SARRP) is poor for localizing small soft tissue targets for irradiation or tumor models growing in a soft tissue environment. Therefore, an imaging method complementary to x-ray CT is required to localize the soft tissue target's Center of Mass (CoM) to within 1 mm. In this paper, we report the development of an integrated x-ray/bioluminescence imaging/tomography (BLI/BLT) system to provide a pre-clinical, high resolution irradiation system. This system can be used to study radiation effects in small animals under the conebeam computed tomography (CBCT) imaging guidance by adding the bioluminescence imaging (BLI) system as a standalone system which can also be docked onto the SARRP. The proposed system integrates two robotic rotating stages and an x-ray source rated at maximum 130 kVp and having a small variable focal spot. A high performance and low noise CCD camera mounted in a light-tight housing along with an optical filter assembly is used for multi-wavelength BL tomography. A three-mirror arrangement is implemented to eliminate the need of rotating the CCD camera for acquiring multiple views. The mirror system is attached to a motorized stage to capture images in angles between 0-90° (for the standalone system). Camera and CBCT calibration are accomplished.
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Affiliation(s)
- S Eslami
- ERC - Computer-Integrated Surgical Systems and Technology (CISST), Johns Hopkins University, Baltimore, MD USA
| | - Y Yang
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - J Wong
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - M S Patterson
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, Canada
| | - I Iordachita
- ERC - Computer-Integrated Surgical Systems and Technology (CISST), Johns Hopkins University, Baltimore, MD USA
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