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At least 19 recordsLinked to original sources
PubMed1978

Determination of glial fibrillary acidic protein (GFAP) in human brain tumors.

Brain tumors have been tested for their glial fibrillary acidic protein (GFAP) content by means of the rocket electrophoresis technique. Meningiomas and neurinomas were low in GFAP. Metastases had a low level of GFAP except when contaminated with surrounding tissue. Non-nervous tumors such as myeloma, myeloplaxoma and adenocarcinoma gave negative results. More detailed correlations with histological observations have been looked for in glial tumors. Low levels of GFAP were always associated with signs of malignancy such as mitoses and giant or atypical cells, whereas high levels of GFAP were correlated with the presence of well-preserved astrocytes.

Adolescent↗
PubMed1977

Case report: chronic graphite granulomatous abscess simulating a brain tumor.

Brain abscess can develop at the site of retained intracranial foreign bodies many years after the injury. This report describes a 6 1/2-year-old child who presented with recurrent severe headaches and a focal seizure of the right upper extremity. Skull X-ray was normal. Computed tomography of the head showed a mass in the left temporoparietal region with a central area of high density and contrast enhancement, thought to be a neoplasm. The mass was seen on the radionuclide brain scan and was avascular on angiography. Craniotomy revealed a foreign body granuloma with a small abscess cavity and a retained piece of pencil graphite. No one in the family could recall if the child had had such an injury.

Brain↗
PubMed1977

Brain-tumor chemotherapy. Pharmacological principles derived from a monkey brain-tumor model.

An implnated choriocarcinoma growing inthe brains of monkeys was used as a brain-tumor model for the study of the cerebral distribution of two commonly used physiological markers, inulin and albumin; tissue samples were obtained from the tumor, adjacent brain, and distant brain. An extravascular inulin space was calculated by subtracting the albumin (plasma) space from the total inulin spaces. The extravascular inulin space in the tumor was found to be 24%, a value significantly larger than that in distant brain (0.6%). The large inulin space of the tumor was probably the result of increases on both capillary permeability and the extracellular space within this area. Determination of the inulin space in 1 to 2-mm thick samples of tissue taken serially from the tumor center to the distant brain indicated a gradual decline in inulin concentration from the tumor's edge to distant brain. This distribution pattern could be the result of either a continuous decrease, running from the tumor to distant brain, in capillary permeability to inulin, or a diffusional flow of inulin from the tumor into the adjacent tissue. The failure of drugs to inhibit such a tumor in view of these observations is discussed.

Albumins↗
PubMed1979

Macrophages in experimental and human brain tumors. Part 2: studies of the macrophage content of human brain tumors.

The authors have analyzed 47 tumors of the central nervous system (11 glioblastomas, nine meningiomas, three medulloblastomas, 12 assorted primary neural tumors, and 12 brain metastases) for their content of macrophages. Cell suspensions were prepared by enzymatic digestion and macrophages were quantitated by IgGEAC rosette formation. Adsorption of sensitized indicator cells (EA) to sections of tumor was used as a measure to determine the distribution of IgGFc receptor-positive cells within the tumors and to serve as a control for selective release of IgGFc receptor-positive cells by enzyme digestion. The 11 glioblastomas had a mean macrophage content of 45% (range: 8% to 78%), the nine meningiomas had a mean of 44% (range: 5% to 81%), the three medulloblastomas a mean of 6% (range 2% to 15%), and the metastatic tumors a mean of 24% (range: 4% to 70%). Adsorption of EA demonstrated that IgGFc receptor-positive cells were distributed throughout the tumor mass, although different types of patterns were observed. There was an excellent correlation between the percent of IgGEAC positive cells in suspensions and the extent of EA adsorption to the tumor sections. Compared to systemic neoplasms, most nervous system tumors have a high macrophage content. It is possible that the high macrophage content of brain tumors is related to their immunogenicity, and may be a partial explanation for tha rarity of brain-tumor metastases.

Brain Neoplasms↗
PubMed1979

Macrophages in experimental and human brain tumors. Part 1: Studies of the macrophage content of experimental rat brain tumors of varying immunogenicity.

Although the presence of lymphoreticular cells within tumors has been recognized for over 100 years, it is only within the last decade that the concept has arisen that standard histological examination techniques may lead to an underestimation of the true extent of tumor infiltration by lymphoreticular cells, and particularly by macrophages. The macrophage content of certain systemic tumors has been correlated with their immunogenicity and growth characteristics. Since the central nervous system is to some extent an "immunologically privileged site" and contains within it specialized reticuloendothelial cells called microglia, the authors determined the macrophage content of three rodent brain-tumor cell lines, and attempted to correlate this macrophage content with their immunogenicity and growth characteristics. Their findings indicate a direct correlation between the immunogenicity and macrophage content of these three neural tumor cell lines.

Animals↗
PubMed2024

Nrf2/Keap1/ARE regulation by plant secondary metabolites: a new horizon in brain tumor management.

Brain cancer is regarded as one of the most life-threatening forms of cancer worldwide. Oxidative stress acts to derange normal brain homeostasis, thus is involved in carcinogenesis in brain. The Nrf2/Keap1/ARE pathway is an important signaling cascade responsible for the maintenance of redox homeostasis, and regulation of anti-inflammatory and anticancer activities by multiple downstream pathways. Interestingly, Nrf2 plays a somewhat, contradictory role in cancers, including brain cancer. Nrf2 has traditionally been regarded as a tumor suppressor since its cytoprotective functions are considered to be the principle cellular defense mechanism against exogenous and endogenous insults, such as xenobiotics and oxidative stress. However, hyperactivation of the Nrf2 pathway supports the survival of normal as well as malignant cells, protecting them against oxidative stress, and therapeutic agents. Plants possess a pool of secondary metabolites with potential chemotherapeutic/chemopreventive actions. Modulation of Nrf2/ARE and downstream activities in a Keap1-dependant manner, with the aid of plant-derived secondary metabolites exhibits promise in the management of brain tumors. Current article highlights the effects of Nrf2/Keap1/ARE cascade on brain tumors, and the potential role of secondary metabolites regarding the management of the same.

Animals↗
PubMed2025

Microbial signals in primary and metastatic brain tumors.

Gliomas and brain metastases are associated with poor prognosis, necessitating a deeper understanding of brain tumor biology and the development of effective therapeutic strategies. Although our group and others have demonstrated microbial presence in various tumors, recent controversies regarding cancer-type-specific intratumoral microbiota emphasize the importance of rigorous, orthogonal validation. This prospective, multi-institutional study included a total of 243 samples from 221 patients, comprising 168 glioma and brain metastases samples and 75 non-cancerous or tumor-adjacent tissues. Using stringent fluorescence in situ hybridization, immunohistochemistry and high-resolution spatial imaging, we detected intracellular bacterial 16S rRNA and lipopolysaccharides in both glioma and brain metastases samples, localized to tumor, immune and stromal cells. Custom 16S and metagenomic sequencing workflows identified taxa associated with intratumoral bacterial signals in the tumor microenvironment; however, standard culture methods did not yield readily cultivable microbiota. Spatial analyses revealed significant correlations between bacterial 16S signals and antimicrobial and immunometabolic signatures at regional, neighborhood and cellular levels. Furthermore, intratumoral 16S bacterial signals showed sequence overlap with matched oral and gut microbiota, suggesting a possible connection with distant communities. Together, these findings introduce microbial elements as a component of the brain tumor microenvironment and lay the foundation for future mechanistic and translational studies.

Humans↗
PubMed2025

Individualized patient tumor organoids faithfully preserve human brain tumor ecosystems and predict patient response to therapy.

Tumor organoids are important tools for cancer research, but current models have drawbacks that limit their applications for predicting response to therapy. Here, we developed a fast, efficient, and complex culture system (IPTO, individualized patient tumor organoid) that accurately recapitulates the cellular and molecular pathology of human brain tumors. Patient-derived tumor explants were cultured in induced pluripotent stem cell (iPSC)-derived cerebral organoids, thus enabling culture of a wide range of human tumors in the central nervous system (CNS), including adult, pediatric, and metastatic brain cancers. Histopathological, genomic, epigenomic, and single-cell RNA sequencing (scRNA-seq) analyses demonstrated that the IPTO model recapitulates cellular heterogeneity and molecular features of original tumors. Crucially, we showed that the IPTO model predicts patient-specific drug responses, including resistance mechanisms, in a prospective patient cohort. Collectively, the IPTO model represents a major breakthrough in preclinical modeling of human cancers, which provides a path toward personalized cancer therapy.

Humans↗
PubMed1979

Dihydrofolate reductase in primary brain tumors, cell cultures of central nervous system origin, and normal brain during fetal and neonatal growth.

Dihydrofolate reductase (DHFR) was measured during the development in rats of brain tumors induced following inoculation with avian sarcoma virus. Increasing activity of this enzyme in brain was correlated with the course of primary brain tumor growth. The specific activities of DHFR in primary human brain tumor tissues were comparable to those found in avian sarcoma virus-induced brain tumors in rats. Specific activities of DHFR in cell cultures derived from human and rat primary intracranial gliomas and sarcomas were up to 6 times those found in adult rat liver. The presence of DHFR in neoplasms of central nervous system origin is relevant to the development of folate antagonists which, unlike methotrexate, can readily cross the blood-brain barrier. In normal developing rat brain, DHFR specific activity was high in embryos at 19 days of gestation and declined thereafter, until at 20 days after birth the activity was very low. The methotrexate titration assay was used to measure enzyme levels in the brains of fetal and newborn rats, and good correlation with the spectrophotometric assay was observed. The pattern was different in liver, showing maximum activity 11 days after birth and retaining high activity in adult liver. Both the cofactor requirement and the sensitivity to methotrexate indicate that the enzyme in the brain is DHFR.

Animals↗
PubMed1979

Morphological, immunocytochemical and biological characteristics of experimental rabbit brain tumors in tissue culture.

Brain tumors were induced in 3-month-old rabbits of either sex by repeated intravenous injections of N-methyl-N-nitrosourea. Twelve brain tumors (6 pleomorphic gliomas, 5 grade 2--3 astrocytomas, 1 grade 2--3 oligodendroglioma) were established in culture and, with the exception of 2 neoplasms, were propagated in vitro as permanent cell lines. The glial nature of all cell lines was ascertained at several passage levels by testing the cells for the production of S-100 and GFA. It could be shown that most cells of all lines fluoresced positively for the S-100 protein, albeit differences in intensity of fluorescence were clearly noted between cells of the same culture and between different cultures. In general, astrocytoma cell lines had the strongest fluorescence. Pleomorphic glioma cells but especially astrocytoma cells reacted positively also for the GFA protein. Surprisingly enough, isolated cells of the oligodendroglioma line also showed evidence of GFA production. Exposure of cultures of rabbit glioma cells to db-cAMP for 8--10 hr resulted in inhibition of cell proliferation and stimulation of process formation. Furthermore, positive fluorescence for the S-100 and GFA proteins was more intense in cells treated with db-cAMP than in untreated cells. The latter observation may indicate that production and/or accumulation of glial proteins also was enhanced during the stationary phase of cell cultures.

Animals↗
PubMed1979

Human brain tumor transplantation into nude mice.

Seven human brain tumors were transplanted into the brains (6/7 takes) and subcutaneous tissues (7/7 takes) of athymic nude mice. Compared to experimental animal brain tumors, these tumors, taken directly from patients in the operating room and transplanted, grew more slowly in the mice; their growth rates following explant generally paralleled those in the patients. A rough correlation was seen between the degree of the tumor's malignancy and both successful take and rate of growth following explant. The tumors' growth rates increased during serial transplantation after explant. Two tumors developed into long-term serial lines; both came from gliosarcomas. Preliminary chemotherapy experiments with these two lines demonstrated different chemosensitivities. One line was very sensitive to the nitrosoureas and resistant to procarbazine; the other line was more sensitive to procarbazine than to the nitrosoureas. This model permits study of the biologic behavior of human brain tumors growing intracerebrally and subcutaneously in nude mice.

Animals↗
PubMed2026

Assessment of the role and effectiveness of nurse-led multimodal intervention in the rehabilitation of dysphagia in patients with brain tumors.

BACKGROUND: Dysphagia is a common complication in patients with brain tumors, which has a profound adverse impact on patients' health status and quality of life. However, there is a relative lack of research on the rehabilitation of dysphagia in brain tumor patients, especially regarding the role and effectiveness of nurse-led multimodal interventions in the rehabilitation of dysphagia in brain tumor patients, which lacks systematic assessment and in-depth discussion. AIM: This study aimed to evaluate the role and effectiveness of a nurse-led multimodal intervention in improving swallowing function and quality of life in brain tumor patients with dysphagia. METHODS: In this study, a randomized controlled trial (RCT) design was used to select 120 dysphagia patients among brain tumor patients admitted to our hospital during the period of January 2024 to May 2024 as the study subjects, and they were stratified and randomly divided into an intervention group (n&#x2009;=&#x2009;60) and a control group (n&#x2009;=&#x2009;60). While the control group received conventional nursing care and treatment protocols, the intervention group received a nurse-led multimodal intervention program, including personalized swallowing training, nutritional support, psychological care, and a family-participatory rehabilitation program, which was developed and dynamically adjusted by nurses, rehabilitation therapists, and dietitians. Differences in data before and after the intervention were analyzed using the paired t-test or Wilcoxon signed-rank test, and between-group comparisons were made using the independent samples t-test or Mann-Whitney U test. RESULTS: Both the intervention and control groups showed improvement in swallowing function among the patients. The Kubota drinking test score, Saito's swallowing function grading, and the quality of life scores for patients in the intervention group showed a significant enhancement compared to those in the control group (P&#x2009;<&#x2009;0.05), indicating that the intervention was more effective than the control. When compared within groups, all scores in both the intervention and control groups improved gradually with the time of intervention (P&#x2009;<&#x2009;0.05). The improvement was significantly higher in the intervention group than in the control group. CONCLUSION: This study demonstrates that a nurse-led multimodal intervention is significantly effective in improving swallowing function and quality of life in patients with brain tumors. The intervention provides comprehensive rehabilitation support for patients through multidisciplinary collaboration and personalized care and has certain clinical promotion value.

Humans↗
PubMed1978

[Immunological examination in patients with brain tumor and the usefulness of PHA skin test (author's transl)].

The usefulness of in vivo skin test reaction to phytohemagglutinin to assess cell-mediated immunity was investigated in 109 subjects, including 37 normal controls, 35 patients without brain tumor and 37 patients with brain tumor. Intradermal injection at forearm of 10 microgram of Bacto-phytohemagglutinin-P (PHA-P) produced an erythema within 24 hours. Upon PHA skin reaction the mean diameter of erythema was 25.3 mm with the normal in the control and 18.6 mm with other diseases than brain tumor, while it was 13.0 mm with brain tumor. Furthermore when mean diameter of those with longer than 15.0 mm are classified as positive in the PHA skin test, the normal in the control revealed 89.2% positive and the patients with brain tumor indicated only 37.8% positive. A positive reaction was observed in 10 (77.0%) of 13 benign brain tumor and 5 (26.3%) of 19 malignant brain tumor. A correlation was found between in vivo and in vitro responses to PHA, and between PHA and PPD skin reaction. In repeated PHA skin test at intervals of about one month, the skin reaction to PHA of patients with brain tumor varied depending on the clinical states. Other advantages of this test are no presensitization and it can be used repeatedly. The PHA skin test is a useful and simple screening test for cellular immune function of patients with brain tumor and as a simple method applicable clinically indicating accurate immuno-reactivity the PHA skin tests have been carried out during the course of treatment with an interval of about one month repeatedly.

Adenoma↗
PubMed1979

Risk factors for brain tumors in children.

An exploratory case-control study was conducted in 15 hospitals in the Baltimore, MD, SMSA of possible etiologic factors associated with brain tumors in children. Eighty-four children with brain tumors were compared to normal children and to children with other malignancies. Parents of these children were interviewed about a variety of possible etiologic factors. The findings included: 1) children with brain tumors as well as children with other cancers had a greater tendency than normal children to have been first births and to have had higher birth weights; 2) more children with brain tumors had a sibling with epilepsy or seizures than did normal children, and several of the mothers of children with brain tumors had themselves had epilepsy or a stroke at a relatively young age; 3) there were no significant differences between the groups with regard to several maternal characteristics, including smoking during pregnancy and prior radiation exposure; 4) more children with brain tumors and children with other cancers were found to have had exposures to insecticides than had normal children; 5) fewer children with brain tumors or with other cancers were reported to have had tonsillectomies than normal children; and 6) more of the children with brain tumors as well as the children with other malignancies were reported to have been exposed to farm animals and to sick pets. This exploratory study is one of the first case-control studies of the epidemiology of brain tumors in children, and the results suggest directions for future epidemiologic studies in this relatively uncharted field.

Adolescent↗
PubMed1977

[RI cisternography in the diagnosis of brain tumors (author's transl)].

Fifteen cases of brain tumors of supratentorial location were studied by RI cisternography; Cisternographical patterns of decreased or absent radioactivity were classified into five groups as follows: Pattern I: Sharply circumscribed and localized decrease in radioactivity; Pattern II:Ill-defined and focal decrease in radioactivity; Pattern III: Areal decrease in radioactivity involving one whole or two lobes; Pattern IV: Hemispherical decrease in radioactivity and Pattern V: Total decrease in radioactivity in the head. Each pattern appears to correspond well with topographical features of brain tumors and their related pathology, such as extracerebral tumors (pattern I), intracerebral but superficially located tumors (pattern II), extracerebral tumors with surrounding edema or large intracerebral tumors (pattern III), extracerebral or intracerebral tumors with increased intracranial pressure (pattern IV), and extremely increased intracranial pressure regardless the site of tumor (pattern V). In consideration of these patterns, RI cisternography would be a more useful supplementary method in diagnosis of brain tumors to detect the area involved, to differentiate an intracerebral from an extracerebral tumor, and to find a recurrence of the tumormfurthermore, it is helpful to know the therapeutical effects of surgery and radiotherapy. RI cisternography is a simple, relatively noninvasive method which can be used more widely.

Adolescent↗