scholarly journals Brain tumours, brain metastases, and neuroinflammation: Insights from neuroimaging studies.

Author(s):  
Rafael Roesler ◽  
Simone Dini ◽  
Gustavo Isolan

Brain tumors and brain metastases induce changes in brain tissue remodelling that lead to immunosuppression and trigger an inflammatory response within the tumor microenvironment. These immune and inflammatory changes can influence invasion and metastasis. Other neuroinflammatory and necrotic lesions may occur in patients with brain cancer or brain metastases as sequelae from treatment with radiotherapy. Glioblastoma (GBM) is the most aggressive primary malignant brain cancer in adults. Imaging methods such as positron-emission tomography (PET) and different magnetic resonance imaging (MRI) techniques are highly valuable for the diagnosis and therapeutic evaluation of GBM and other malignant brain tumors. However, differentiating between tumor tissue and inflamed brain tissue with imaging protocols remains a challenge. Here, we review recent advances in imaging methods that have helped to improve the specificity of primary tumor diagnosis versus evaluation of inflamed and necrotic brain lesions. We also comment on advances in differentiating metastasis from neuroinflammation processes. Recent advances include the radiosynthesis of 18F-FIMP, an L-type amino acid transporter 1 (LAT1)-specific PET probe that allows better differentiation between tumor tissue and inflammation compared to previous probes; and the combination different advanced imaging protocols with the inclusion of radiomics and machine learning algorithms.

2020 ◽  
Vol 196 (10) ◽  
pp. 856-867 ◽  
Author(s):  
Martin Kocher ◽  
Maximilian I. Ruge ◽  
Norbert Galldiks ◽  
Philipp Lohmann

Abstract Background Magnetic resonance imaging (MRI) and amino acid positron-emission tomography (PET) of the brain contain a vast amount of structural and functional information that can be analyzed by machine learning algorithms and radiomics for the use of radiotherapy in patients with malignant brain tumors. Methods This study is based on comprehensive literature research on machine learning and radiomics analyses in neuroimaging and their potential application for radiotherapy in patients with malignant glioma or brain metastases. Results Feature-based radiomics and deep learning-based machine learning methods can be used to improve brain tumor diagnostics and automate various steps of radiotherapy planning. In glioma patients, important applications are the determination of WHO grade and molecular markers for integrated diagnosis in patients not eligible for biopsy or resection, automatic image segmentation for target volume planning, prediction of the location of tumor recurrence, and differentiation of pseudoprogression from actual tumor progression. In patients with brain metastases, radiomics is applied for additional detection of smaller brain metastases, accurate segmentation of multiple larger metastases, prediction of local response after radiosurgery, and differentiation of radiation injury from local brain metastasis relapse. Importantly, high diagnostic accuracies of 80–90% can be achieved by most approaches, despite a large variety in terms of applied imaging techniques and computational methods. Conclusion Clinical application of automated image analyses based on radiomics and artificial intelligence has a great potential for improving radiotherapy in patients with malignant brain tumors. However, a common problem associated with these techniques is the large variability and the lack of standardization of the methods applied.


2019 ◽  
Vol 12 ◽  
pp. 251686571984028 ◽  
Author(s):  
Javier IJ Orozco ◽  
Ayla O Manughian-Peter ◽  
Matthew P Salomon ◽  
Diego M Marzese

DNA methylation profiling has proven to be a powerful analytical tool, which can accurately identify the tissue of origin of a wide range of benign and malignant neoplasms. Using microarray-based profiling and supervised machine learning algorithms, we and other groups have recently unraveled DNA methylation signatures capable of aiding the histomolecular diagnosis of different tumor types. We have explored the methylomes of metastatic brain tumors from patients with lung cancer, breast cancer, and cutaneous melanoma and primary brain neoplasms to build epigenetic classifiers. Our brain metastasis methylation (BrainMETH) classifier has the ability to determine the type of brain tumor, the origin of the metastases, and the clinical-therapeutic subtype for patients with breast cancer brain metastases. To facilitate the translation of these epigenetic classifiers into clinical practice, we selected and validated the most informative genomic regions utilizing quantitative methylation-specific polymerase chain reaction (qMSP). We believe that the refinement, expansion, integration, and clinical validation of BrainMETH and other recently developed epigenetic classifiers will significantly contribute to the development of more comprehensive and accurate systems for the personalized management of patients with brain metastases.


Author(s):  
S. Marbacher ◽  
E. Klinger ◽  
L. Schwzer ◽  
I. Fischer ◽  
E. Nevzati ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Geetika Nehra ◽  
Shannon Andrews ◽  
Joan Rettig ◽  
Michael N. Gould ◽  
Jill D. Haag ◽  
...  

AbstractPerillyl alcohol (POH) has been extensively studied for the treatment of peripheral and primary brain tumors. The intranasal route of administration has been preferred for dosing POH in early-stage clinical trials associated with promising outcomes in primary brain cancer. However, it is unclear how intranasal POH targets brain tumors in these patients. Multiple studies indicate that intranasally applied large molecules may enter the brain and cerebrospinal fluid (CSF) through direct olfactory and trigeminal nerve-associated pathways originating in the nasal mucosa that bypass the blood–brain barrier. It is unknown whether POH, a small molecule subject to extensive nasal metabolism and systemic absorption, may also undergo direct transport to brain or CSF from the nasal mucosa. Here, we compared CSF and plasma concentrations of POH and its metabolite, perillic acid (PA), following intranasal or intravascular POH application. Samples were collected over 70 min and assayed by high-performance liquid chromatography. Intranasal administration resulted in tenfold higher CSF-to-plasma ratios for POH and tenfold higher CSF levels for PA compared to equal dose intravascular administration. Our preclinical results demonstrate POH undergoes direct transport from the nasal mucosa to the CSF, a finding with potential significance for its efficacy as an intranasal chemotherapeutic for brain cancer.


NAR Cancer ◽  
2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Keisuke Katsushima ◽  
George Jallo ◽  
Charles G Eberhart ◽  
Ranjan J Perera

Abstract Long non-coding RNAs (lncRNAs) have been found to be central players in the epigenetic, transcriptional and post-transcriptional regulation of gene expression. There is an accumulation of evidence on newly discovered lncRNAs, their molecular interactions and their roles in the development and progression of human brain tumors. LncRNAs can have either tumor suppressive or oncogenic functions in different brain cancers, making them attractive therapeutic targets and biomarkers for personalized therapy and precision diagnostics. Here, we summarize the current state of knowledge of the lncRNAs that have been implicated in brain cancer pathogenesis, particularly in gliomas and medulloblastomas. We discuss their epigenetic regulation as well as the prospects of using lncRNAs as diagnostic biomarkers and therapeutic targets in patients with brain tumors.


1982 ◽  
Vol 2 (1) ◽  
pp. 25-32 ◽  
Author(s):  
K.-A. Hossmann ◽  
I. Niebuhr ◽  
M. Tamura

Experimental brain tumors were produced in rats by intracerebral implantation of a neoplastic glial cell clone. Within 2–6 weeks, spherical brain tumors developed at the implantation site with a mean diameter of 6 mm. Local blood flow and local glucose utilization were measured under light barbiturate anesthesia by quantitative autoradiography in the tumor and peritumoral brain tissue. In solid parts of the tumor, blood flow was 57.8 ± 2.0 ml/100 g/min (mean ± SE), and glucose utilization was 87.2 ± 5.8 μmol/100 g/min, respectively. In necrotic regions, flow and glucose utilization were zero. In peritumoral brain tissue of the ipsilateral hemisphere blood flow was reduced by 13–23%, as compared to homologous regions of the opposite side, the greatest decrease being recorded in the ipsilateral thalamus. Flow in the opposite hemisphere was of the same order of magnitude as in normal control rats. Glucose consumption, in contrast, was distinctly reduced in both hemispheres: in the cortex and putamen, it was 40–50% lower than in normal controls. The following conclusions are drawn: (1) during tumor development the high glucose consumption in the tumor tissue is not coupled to an equal increase in blood flow; (2) peritumoral cerebral blood flow decreases on the ipsilateral but not on the contralateral side, and (3) the metabolic rate of glucose is distinctly inhibited in both hemispheres of tumor-bearing animals. The dissociation between blood flow and metabolism suggests that metabolic inhibition is not the consequence of a diaschitic depression of functional activity.


2021 ◽  
Vol 66 (12) ◽  
pp. 718-721
Author(s):  
Larisa Mikhailovna Obukhova ◽  
I. A. Medyanik ◽  
K. N. Kontorshchikova ◽  
S. A. Simagina ◽  
L. T. Musaelyan ◽  
...  

It has been established that the non-neuronal cholinergic system is related to the oncogenesis which increases the attractiveness of its components as the promising markers of oncologic diseases. The purpose of this work is to evaluate the clinical significance of the analysis of the activity of acetyl cholinesterase as a new marker of gliomas. The activity of acetyl cholinesterase was assessed by photo colorimetric analysis according to the Hestrin method recalculating the activity of the enzyme in the tumor tissue per 1 g of protein, and in the blood - by 0.1 g of hemoglobin. The data obtained in the primary tumors of the brain (28) in the tissue of the brain of persons who died as a result of injury (6) and in whole blood of patients with gliomas (28) and practically healthy people (10) were compared with the use of a number of statistical programs. A significant decrease in the activity of acetyl cholinesterase in tumor tissue and in whole blood is revealed as the degree of anaplasia of tumors increases, starting with Grade II. It is for the first time that a significant direct correlation was noted showing the consistency between the decrease in the activity of acetyl cholinesterase in the tumor tissue of the brain and blood. Bioinformatic analysis showed the connection of the enzyme of acetyl cholinesterase with proteins of the PI3K-AKT and Notch signaling pathways providing antiapoptotic and proliferative effects. The found dependences provide new insights into understanding of the mechanisms of gliomas genesis and can be used for selection of new diagnostic markers of brain tumors.


2014 ◽  
Vol 33 (04) ◽  
pp. 347-351
Author(s):  
Pedro Tadao Hamamoto Filho ◽  
Vitor César Machado ◽  
Flávio Ramalho Romero ◽  
Luis Gustavo Ducati ◽  
Marco Antônio Zanini ◽  
...  

AbstractBrain metastases are the most common tumors within the central nervous system. Recent advances on diagnosis and treatment modalities have allowed for longer survival. In this paper we review the indication of each modality of treatment: surgery, whole brain radiotherapy and stereotactic radiosurgery, as also recent advances on the knowledge of brain metastases biology that may improve the use of medical treatment and chemotherapy.


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