scholarly journals Tumor Microenvironment Modifications Recorded With IVIM Perfusion Analysis and DCE-MRI After Neoadjuvant Radiotherapy: A Preclinical Study

2021 ◽  
Vol 11 ◽  
Author(s):  
François Lallemand ◽  
Natacha Leroi ◽  
Silvia Blacher ◽  
Mohamed Ali Bahri ◽  
Evelyne Balteau ◽  
...  

PurposeNeoadjuvant radiotherapy (NeoRT) improves tumor local control and facilitates tumor resection in many cancers. Some clinical studies demonstrated that both timing of surgery and RT schedule influence tumor dissemination, and subsequently patient overall survival. Previously, we developed a pre-clinical model demonstrating the impact of NeoRT schedule and timing of surgery on metastatic spreading. We report on the impact of NeoRT on tumor microenvironment by MRI.MethodsAccording to our NeoRT model, MDA-MB 231 cells were implanted in the flank of SCID mice. Tumors were locally irradiated (PXI X-Rad SmART) with 2x5Gy and then surgically removed at different time points after RT. Diffusion-weighted (DW) and Dynamic contrast enhancement (DCE) MRI images were acquired before RT and every 2 days between RT and surgery. IntraVoxel Incoherent Motion (IVIM) analysis was used to obtain information on intravascular diffusion, related to perfusion (F: perfusion factor) and subsequently tumor vessels perfusion. For DCE-MRI, we performed semi-quantitative analyses.ResultsWith this experimental model, a significant and transient increase of the perfusion factor F [50% of the basal value (n=16, p<0.005)] was observed on day 6 after irradiation as well as a significant increase of the WashinSlope with DCE-MRI at day 6 (n=13, p<0.05). Using immunohistochemistry, a significant increase of perfused vessels was highlighted, corresponding to the increase of perfusion in MRI at this same time point. Moreover, Tumor surgical resection during this peak of vascularization results in an increase of metastasis burden (n=10, p<0.05).ConclusionSignificant differences in perfusion-related parameters (F and WashinSlope) were observed on day 6 in a neoadjuvant radiotherapy model using SCID mice. These modifications are correlated with an increase of perfused vessels in histological analysis and also with an increase of metastasis spreading after the surgical procedure. This experimental observation could potentially result in a way to personalize treatment, by modulating the time of surgery guided on MRI functional data, especially tumor perfusion.

Oncotarget ◽  
2015 ◽  
Vol 6 (34) ◽  
pp. 36825-36837 ◽  
Author(s):  
Natacha Leroi ◽  
Nor Eddine Sounni ◽  
Eva Van Overmeire ◽  
Silvia Blacher ◽  
Raphael Marée ◽  
...  

2019 ◽  
Vol 20 (13) ◽  
pp. 1363-1368
Author(s):  
Krisztina B. Gecse ◽  
Christianne J. Buskens

Despite changing medical paradigm, still a significant proportion of patients with IBD require surgery. The patient's general condition, including nutritional status and the use of immunosuppressive medications is of great importance with regard to surgical complications, as well as the choice of optimal surgical strategy. The indication and the timing of surgery are key factors for the multidisciplinary management of IBD patients. The purpose of this review is to provide an overview on the impact of medical treatment on surgical strategies in IBD.


Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 986
Author(s):  
Nada S. Aboelella ◽  
Caitlin Brandle ◽  
Timothy Kim ◽  
Zhi-Chun Ding ◽  
Gang Zhou

It has been well-established that cancer cells are under constant oxidative stress, as reflected by elevated basal level of reactive oxygen species (ROS), due to increased metabolism driven by aberrant cell growth. Cancer cells can adapt to maintain redox homeostasis through a variety of mechanisms. The prevalent perception about ROS is that they are one of the key drivers promoting tumor initiation, progression, metastasis, and drug resistance. Based on this notion, numerous antioxidants that aim to mitigate tumor oxidative stress have been tested for cancer prevention or treatment, although the effectiveness of this strategy has yet to be established. In recent years, it has been increasingly appreciated that ROS have a complex, multifaceted role in the tumor microenvironment (TME), and that tumor redox can be targeted to amplify oxidative stress inside the tumor to cause tumor destruction. Accumulating evidence indicates that cancer immunotherapies can alter tumor redox to intensify tumor oxidative stress, resulting in ROS-dependent tumor rejection. Herein we review the recent progresses regarding the impact of ROS on cancer cells and various immune cells in the TME, and discuss the emerging ROS-modulating strategies that can be used in combination with cancer immunotherapies to achieve enhanced antitumor effects.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A737-A737
Author(s):  
Loise Francisco-Anderson ◽  
Loise Francisco-Anderson ◽  
Mary Abdou ◽  
Michael Goldberg ◽  
Erin Troy ◽  
...  

BackgroundThe small intestinal axis (SINTAX) is a network of anatomic and functional connections between the small intestine and the rest of the body. It acts as an immunosurveillance system, integrating signals from the environment that affect physiological processes throughout the body. The impact of events in the gut in the control of tumor immunity is beginning to be appreciated. We have previously shown that an orally delivered single strain of commensal bacteria induces anti-tumor immunity preclinically via pattern recognition receptor-mediated activation of innate and adaptive immunity. Some bacteria produce extracellular vesicles (EVs) that share molecular content with the parent bacterium in a particle that is roughly 1/1000th the volume in a non-replicating form. We report here an orally-delivered and gut-restricted bacterial EV which potently attenuates tumor growth to a greater extent than whole bacteria or checkpoint inhibition.MethodsEDP1908 is a preparation of extracellular vesicles produced by a gram-stain negative strain of bacterium of the Oscillospiraceae family isolated from a human donor. EDP1908 was selected for its immunostimulatory profile in a screen of EVs from a range of distinct microbial strains. Its mechanism of action was determined by ex vivo analysis of the tumor microenvironment (TME) and by in vitro functional studies with murine and human cells.ResultsOral treatment of tumor-bearing mice with EDP1908 shows superior control of tumor growth compared to checkpoint inhibition (anti-PD-1) or an intact microbe. EDP1908 significantly increased the percentage of IFNγ and TNF producing CD8+ CTLs, NK cells, NKT cells and CD4+ cells in the tumor microenvironment (TME). EDP1908 also increased tumor-infiltrating dendritic cells (DC1 and DC2). Analysis of cytokines in the TME showed significant increases in IP-10 and IFNg production in mice treated with EDP1908, creating an environment conducive to the recruitment and activation of anti-tumor lymphocytes.ConclusionsThis is the first report of striking anti-tumor effects of an orally delivered microbial extracellular vesicle. These data point to oral EVs as a new class of immunotherapeutic drugs. They are particularly effective at harnessing the biology of the small intestinal axis, acting locally on host cells in the gut to control distal immune responses within the TME. EDP1908 is in preclinical development for the treatment of cancer.Ethics ApprovalPreclinical murine studies were conducted under the approval of the Avastus Preclinical Services’ Ethics Board. Human in vitro samples were attained by approval of the IntegReview Ethics Board; informed consent was obtained from all subjects.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xiaojing Shi ◽  
Caiguang Cao ◽  
Zeyu Zhang ◽  
Jie Tian ◽  
Zhenhua Hu

AbstractCerenkov luminescence imaging (CLI) is a novel optical imaging technique that has been applied in clinic using various radionuclides and radiopharmaceuticals. However, clinical application of CLI has been limited by weak optical signal and restricted tissue penetration depth. Various fluorescent probes have been combined with radiopharmaceuticals for improved imaging performances. However, as most of these probes only interact with Cerenkov luminescence (CL), the low photon fluence of CL greatly restricted it’s interaction with fluorescent probes for in vivo imaging. Therefore, it is important to develop probes that can effectively convert energy beyond CL such as β and γ to the low energy optical signals. In this study, a Eu3+ doped gadolinium oxide (Gd2O3:Eu) was synthesized and combined with radiopharmaceuticals to achieve a red-shifted optical spectrum with less tissue scattering and enhanced optical signal intensity in this study. The interaction between Gd2O3:Eu and radiopharmaceutical were investigated using 18F-fluorodeoxyglucose (18F-FDG). The ex vivo optical signal intensity of the mixture of Gd2O3:Eu and 18F-FDG reached 369 times as high as that of CLI using 18F-FDG alone. To achieve improved biocompatibility, the Gd2O3:Eu nanoparticles were then modified with polyvinyl alcohol (PVA), and the resulted nanoprobe PVA modified Gd2O3:Eu (Gd2O3:Eu@PVA) was applied in intraoperative tumor imaging. Compared with 18F-FDG alone, intraoperative administration of Gd2O3:Eu@PVA and 18F-FDG combination achieved a much higher tumor-to-normal tissue ratio (TNR, 10.24 ± 2.24 vs. 1.87 ± 0.73, P = 0.0030). The use of Gd2O3:Eu@PVA and 18F-FDG also assisted intraoperative detection of tumors that were omitted by preoperative positron emission tomography (PET) imaging. Further experiment of image-guided surgery demonstrated feasibility of image-guided tumor resection using Gd2O3:Eu@PVA and 18F-FDG. In summary, Gd2O3:Eu can achieve significantly optimized imaging property when combined with 18F-FDG in intraoperative tumor imaging and image-guided tumor resection surgery. It is expected that the development of the Gd2O3:Eu nanoparticle will promote investigation and application of novel nanoparticles that can interact with radiopharmaceuticals for improved imaging properties. This work highlighted the impact of the nanoprobe that can be excited by radiopharmaceuticals emitting CL, β, and γ radiation for precisely imaging of tumor and intraoperatively guide tumor resection.


2021 ◽  
Vol 22 (7) ◽  
pp. 3578
Author(s):  
Federico Armando ◽  
Adnan Fayyad ◽  
Stefanie Arms ◽  
Yvonne Barthel ◽  
Dirk Schaudien ◽  
...  

Histiocytic sarcomas refer to highly aggressive tumors with a poor prognosis that respond poorly to conventional treatment approaches. Oncolytic viruses, which have gained significant traction as a cancer therapy in recent decades, represent a promising option for treating histiocytic sarcomas through their replication and/or by modulating the tumor microenvironment. The live attenuated canine distemper virus (CDV) vaccine strain Onderstepoort represents an attractive candidate for oncolytic viral therapy. In the present study, oncolytic virotherapy with CDV was used to investigate the impact of this virus infection on tumor cell growth through direct oncolytic effects or by virus-mediated modulation of the tumor microenvironment with special emphasis on angiogenesis, expression of selected MMPs and TIMP-1 and tumor-associated macrophages in a murine xenograft model of canine histiocytic sarcoma. Treatment of mice with xenotransplanted canine histiocytic sarcomas using CDV induced overt retardation in tumor progression accompanied by necrosis of neoplastic cells, increased numbers of intratumoral macrophages, reduced angiogenesis and modulation of the expression of MMPs and TIMP-1. The present data suggest that CDV inhibits tumor growth in a multifactorial way, including direct cell lysis and reduction of angiogenesis and modulation of MMPs and their inhibitor TIMP-1, providing further support for the concept of its role in oncolytic therapies.


Cancers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 335
Author(s):  
Barbara Muz ◽  
Anas Abdelghafer ◽  
Matea Markovic ◽  
Jessica Yavner ◽  
Anupama Melam ◽  
...  

E-selectin is a vascular adhesion molecule expressed mainly on endothelium, and its primary role is to facilitate leukocyte cell trafficking by recognizing ligand surface proteins. E-selectin gained a new role since it was demonstrated to be involved in cancer cell trafficking, stem-like properties and therapy resistance. Therefore, being expressed in the tumor microenvironment, E-selectin can potentially be used to eradicate cancer. Uproleselan (also known as GMI-1271), a specific E-selectin antagonist, has been tested on leukemia, myeloma, pancreatic, colon and breast cancer cells, most of which involve the bone marrow as a primary or as a metastatic tumor site. This novel therapy disrupts the tumor microenvironment by affecting the two main steps of metastasis—extravasation and adhesion—thus blocking E-selectin reduces tumor dissemination. Additionally, uproleselan mobilized cancer cells from the protective vascular niche into the circulation, making them more susceptible to chemotherapy. Several preclinical and clinical studies summarized herein demonstrate that uproleselan has favorable safety and pharmacokinetics and is a tumor microenvironment-disrupting agent that improves the efficacy of chemotherapy, reduces side effects such as neutropenia, intestinal mucositis and infections, and extends overall survival. This review highlights the critical contribution of E-selectin and its specific antagonist, uproleselan, in the regulation of cancer growth, dissemination, and drug resistance in the context of the bone marrow microenvironment.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 768
Author(s):  
Yoann Varenne ◽  
Stéphane Corvec ◽  
Anne-Gaëlle Leroy ◽  
David Boutoille ◽  
Mỹ-Vân Nguyễn ◽  
...  

Resections of primary pelvic bone tumors are frequently complicated by surgical site infections (SSIs), thereby impairing the functional prognosis of patients, especially in case of implant removal. Although prophylactic antibiotics play an essential role in preventing SSIs, there are presently no recommendations that support their appropriate use. This study aimed to assess the impact of a 24 h prophylactic protocol on the bacterial ecology, the resistance pattern, and the SSI healing rate. We hypothesized that this protocol not only limits the emergence of resistance but also results in a good cure rate with implant retention in case of SSI. A retrospective study was performed that included all patients with an SSI following a pelvic bone tumoral resection between 2005 and 2017 who received a 24 h antibiotic prophylaxis protocol. Twenty-nine patients with an SSI were included. We observed a 75.9% rate of polymicrobial infection, with a high prevalence of digestive flora microorganisms and a majority of wild-type phenotypes. We confirmed that there was no significant emergence of resistant flora. After first-line debridement, antibiotics (DA) if any implant was used, or debridement, antibiotics, and implant retention (DAIR) whenever possible, we obtained a 79.3% cure rate, with implant removal in 20% of cases. The absence of an implant was significantly associated with SSI healing. Early infection management and low resistance profiles may also have a positive effect, but this needs to be confirmed in a larger cohort. In light of this, the use of a 24 h prophylactic protocol in primary pelvic bone tumor resections is associated with a favorable infection cure rate and implant retention in case of SSI, and minimal selection of resistant microorganisms.


Sign in / Sign up

Export Citation Format

Share Document