Intraoperative hemorrhage is a life-threatening complication during neurosurgery, especially in posterior fossa surgery, where critical vasculature and brain structures are present. Adenosine has been used in neurovascular surgery, particularly in the management of intraoperative aneurysm rupture and hemorrhage for its ability to produce transient flow arrest. This case report describes a novel application for adenosine, in which adenosine-induced flow arrest was used to facilitate control of a vascular injury sustained during meningioma surgery.

A 46-year-old female diagnosed with a petroclival meningioma after presenting with a several-month history of headache, dizziness, and loss of balance underwent craniotomy and excision of the meningioma. The patient received general endotracheal anesthesia, and was maintained on remifentanil, propofol, and low-dose sevoflurane. During posterior excision of the meningioma, the basilar artery was inadvertently lacerated, resulting in significant blood loss. Adenosine was given through a subclavian catheter, and produced severe bradycardia, hypotension, then asystole for approximately 50 seconds. Adenosine-induced flow arrest allowed for initial control of the vascular injury through coagulation, while further hemostasis was achieved through hemostatic agents and muscle tamponade.

This case report demonstrates the usefulness of adenosine-induced flow arrest in the management of intraoperative hemorrhage from an intracranial vascular injury. Adenosine-induced flow arrest has documented safety and efficacy in other neurosurgical applications. As the management of intraoperative hemorrhage is an essential component of neuroanesthesia, this technique may be considered in similar circumstances of major vascular injury to facilitate hemostasis.

Introduction: Hypernatremia is a common yet high-mortality electrolyte disorder. The hypothalamus maintains water homeostasis via thirst sensation and arginine vasopressin (AVP) secretion. Hypothalamic tumors, such as gliomas, can progressively destroy these osmoregulatory centres, leading to “malignant” hypernatremia (>180 mmol/L). We report a case of life-threatening hypernatremia in a patient with a progressive hypothalamic glioma, exploring its complex pathophysiology. Case: A 41-year-old female with a progressive high-grade hypothalamic glioma and persistent hydrocephalus presented with generalized weakness, reduced oral intake, and dehydration. Her initial Glasgow Coma Scale was E4V3M6. Laboratory investigations revealed malignant hypernatremia (serum sodium 209 mmol/L) and a serum osmolarity of 441 mOsm/kg. Despite life-threatening dehydration (urea 26.2 mmol/L, creatinine 343 umol/L), she was still able to deceptively produce urine output of 400 mL/day with a concentrated urine osmolarity of 890 mOsm/kg. A 1 mcg IV desmopressin trial reduced urine output to 60 mL/day and serum sodium by 10 mmol/L within 14 hours, confirming relative AVP deficiency. The patient’s malignant hypernatremia was gradually corrected to 168 mmol/L over 1 week (8–12 mmol/L/day) using controlled intravenous hydration. However, her condition deteriorated due to hospital-acquired infection, and she succumbed 10 days after admission. Conclusion This case underscores several critical learning points for managing hypothalamic emergencies. First, hypothalamic tumors can reset the osmostat or destroy osmoregulatory centres, causing adipsic AVP deficiency. Second, clinicians must be alert to “masked polyuria” where severe hypovolemia reduces the glomerular filtration rate, causing urine output to appear “normal” despite underlying AVP deficiency. This state of “relative polyuria” is a hallmark of hypothalamic hypernatremia, thus indicating that a normal urine output does not rule out AVP deficiency. While desmopressin is indicated, its use in adipsic patients demands strict fluid titration to prevent iatrogenic hyponatremia. Rapid hypotonic correction carries a proven risk of cerebral oedema, and sodium measurement accuracy varies significantly across laboratory methods in extreme ranges.
Hypernatremia ; Hypothalamic Neoplasms

OBJECTIVES: To investigate the mechanism by which circ_EPHB4 regulates temozolomide (TMZ) sensitivity of glioma cells through the miR-424-5p/Wnt3 signal axis. METHODS: We detected the expression levels of circ_EPHB4, miR-424-5p and Wnt3 mRNA in glioma specimens from 25 patients with primary glioma and 25 patients experiencing relapse following temozolomide-based chemotherapy and in TMZ-sensitive and -resistant glioma A172 and SHG44 cells with circ_EPHB4 knockdown using qRT-PCR, and Wnt3 protein expression level was detected with Western blotting. Cell viability, colony-forming ability, and apoptosis of the cells with circ_EPHB4 knockdown were assessed, and the targeted regulation relationship between circ_EPHB4, miR-424-5p, and Wnt3 was verified by dual luciferase reporter assay and RNA immunoprecipitation (RIP) experiments. The effect of circ_EPHB4 knockdown on tumorigenesis of glioma cells was evaluated in subcutaneous tumor-bearing nude mouse models. RESULTS: The expression of circ_EPHB4 was significantly increased in glioma tissues and cells as compared with normal neural tissues and astrocytes (P=0.014). In TMZ-resistant glioma cells, circ_EPHB4 knockdown resulted in an obvious reduction of IC50 value of TMZ, inhibited cell colony formation, and promoted cell apoptosis, and these effects were reversed by miR-424-5p knockdown. The expressions of miR-424-5p and circ_EPHB4 were negatively correlated in glioma tissues (P=0.011). MiR-424-5p knockdown also attenuated the effect of circ_EPHB4 knockdown on expressions of PCNA, P-gp, MRP1 and bax. CONCLUSIONS Circ_EPHB4 regulates Wnt3 expression through "sponge adsorption" of miR-424-5p, thereby modulating TMZ-resistant glioblastoma cell clonogenesis, apoptosis, and TMZ sensitivity, suggesting the potential of circ_EPHB4 as a therapeutic target for reversing drug resistance of gliomas.
MicroRNAs/genetics* ; Humans ; Temozolomide ; Glioma/genetics* ; Animals ; Mice, Nude ; Cell Line, Tumor ; Wnt3 Protein/metabolism* ; Mice ; Apoptosis ; RNA, Circular ; Drug Resistance, Neoplasm ; Brain Neoplasms/pathology* ; Signal Transduction

OBJECTIVES: To investigate the oncogenic role of circular RNA circ_EPHB4 in glioma and its molecular mechanism. METHODS: Microarray analysis was performed to identify the differentially expressed circRNAs in glioma tissues. The effects of circ_EPHB4 on glioma cell migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and tumorigenicity in vivo were assessed using scratch wound healing assay, Transwell invasion assay and nude mouse models bearing subcutaneous tumors. RNA immunoprecipitation (RIP), RNA stability assays, and gene overexpression and silencing techniques were employed to validate the synergistic regulatory effect of circ_EPHB4 and the N6-methyladenosine (m⁶A) reader protein YTHDF3 on Wnt3 expression. RESULTS: Circ_EPHB4 was significantly overexpressed by 2.3 folds (|log2FC|=1.2, P<0.01) in glioma tissues compared to the adjacent tissues, and by 2.5 folds in glioma cell line U373 compared to normal cells (P<0.001). Overexpression of circ_EPHB4 significantly enhanced migration and invasion of glioma cells, and promoted the expressions of EMT markers N-cadherin and vimentin. In the tumor-bearing mouse models, the tumor volume in circ_EPHB4 overexpression group was significantly greater than that in the control group, and the lung metastatic foci increased by 4.2 folds. Overexpression of circ_EPHB4 promoted oncogenesis by upregulating Wnt3 expression, while YTHDF3 extended the half-life of Wnt3 mRNA in an m⁶A-dependent manner. Simultaneous knockdown of circ_EPHB4 and YTHDF3 resulted in an obvious reduction of Wnt3 mRNA expression by up to 47% compared to its level following knocking down either circ_EPHB4 or YTHDF3 alone. CONCLUSIONS Circ_EPHB4 and YTHDF3 promote glioma progression by jointly targeting the Wnt3 signaling pathway, which may provide a new therapeutic strategy for gliomas.
Glioma/genetics* ; Humans ; Animals ; Cell Line, Tumor ; RNA-Binding Proteins/genetics* ; RNA, Circular ; Epithelial-Mesenchymal Transition ; Mice, Nude ; Cell Movement ; Wnt3 Protein/genetics* ; Mice ; Disease Progression ; Adenosine/metabolism* ; Brain Neoplasms/metabolism* ; Gene Expression Regulation, Neoplastic

Iron metabolism is a critical factor in tumorigenesis and development. Although TP53 mutations are prevalent in glioblastoma (GBM), the mechanisms by which TP53 regulates iron metabolism remain elusive. We reveal an imbalance iron homeostasis in GBM via TCGA database analysis. TP53 mutations disrupted iron homeostasis in GBM, characterized by elevated total iron levels and reduced ferritin (FTH). The gain-of-function effect triggered by TP53 mutations upregulates itchy E3 ubiquitin-protein ligase (ITCH) protein expression in astrocytes, leading to FTH degradation and an increase in free iron levels. TP53-mut astrocytes were more tolerant to the high iron environment induced by exogenous ferric ammonium citrate (FAC), but the increase in intracellular free iron made them more sensitive to Erastin-induced ferroptosis. Interestingly, we found that Erastin combined with FAC treatment significantly increased ferroptosis. These findings provide new insights for drug development and therapeutic modalities for GBM patients with TP53 mutations from iron metabolism perspectives.
Ferroptosis/drug effects* ; Humans ; Iron/metabolism* ; Glioblastoma/metabolism* ; Tumor Suppressor Protein p53/metabolism* ; Homeostasis/physiology* ; Ferritins/metabolism* ; Brain Neoplasms/genetics* ; Mutation ; Astrocytes/drug effects* ; Cell Line, Tumor ; Piperazines/pharmacology* ; Quaternary Ammonium Compounds/pharmacology* ; Ferric Compounds

Glioma, the most prevalent primary tumor of the central nervous system (CNS), is also the most lethal primary malignant tumor. Currently, there are limited chemotherapeutics available for glioma treatment, necessitating further research to identify and develop new chemotherapeutic agents. A significant approach to discovering anti-glioma drugs involves isolating antitumor active ingredients from natural products (NPs) and optimizing their structures. Additionally, targeted drug delivery systems (TDDSs) are employed to enhance drug solubility and stability and overcome the blood-brain barrier (BBB). TDDSs can penetrate deep into the brain, increase drug concentration and retention time in the CNS, and improve the targeting efficiency of NPs, thereby reducing adverse effects and enhancing anti-glioma efficacy. This paper reviews the research progress of anti-glioma activities of NPs, including alkaloids, polyphenols, flavonoids, terpenoids, saponins, quinones, and their synthetic derivatives over the past decade. The review also summarizes anti-glioma mechanisms, such as suppression of related protein expression, regulation of reactive oxygen species (ROS) levels, control of apoptosis signaling pathways, reduction of matrix metalloproteinases (MMPs) expression, blocking of vascular endothelial growth factor (VEGF), and reversal of immunosuppression. Furthermore, the functions and advantages of NP-based TDDSs in anti-glioma therapy are examined. The key information presented in this review will be valuable for the research and development of NP-based anti-glioma drugs and related TDDSs.
Humans ; Glioma/metabolism* ; Biological Products/therapeutic use* ; Animals ; Brain Neoplasms/genetics* ; Drug Delivery Systems ; Antineoplastic Agents/therapeutic use* ; Blood-Brain Barrier/metabolism* ; Apoptosis/drug effects*

Most tumor cells and healthy neurons are at rest during G0 phase.Once the cell cycle is abnormally re-entered under certain conditions,the proliferation of tumor cells and the degenerative necrosis of neurons can be initiated.From the perspective of the cell cycle,cancer and central nervous system diseases,two seemingly different disease types,have a common pathogenesis.This type of diseases is named aberrant cell cycle diseases.As a newly discovered microRNA(miR),miR-1976 is closely related to the regulation of the cell cycle.This review summarizes the progress in the research on miR-1976 in cancer and central nervous system diseases,aiming to provide a reference for the clinical application of miR-1976 in aberrant cell cycle diseases in the future.
MicroRNAs/genetics* ; Humans ; Cell Cycle/genetics* ; Neoplasms/genetics* ; Central Nervous System Diseases/genetics*

BACKGROUND AND OBJECTIVE

Meningiomas represent the most prevalent benign intracranial tumors, comprising 13- 26% of primary intracranial neoplasms. These tumors derive their blood supply from both extracranial and intracranial circulation. Over recent decades, pre-operative embolization (POE) has emerged as a potential adjunctive therapy to surgery, aiming to reduce tumor vascularity. Our study seeks to explore the potential correlation between the extent of devascularization following POE of meningiomas and intraoperative blood loss.

This cross-sectional study involved nine meningioma patients at a tertiary hospital, involving chart review of patients across four years. These patients were referred for POE due to angiographic evidence of a hypervascular mass between January 2018 and January 2022. We collected demographic data, tumor characteristics (including location, size, and vascular supply), and intraoperative variables such as total operative time and blood loss. Statistical analyses aimed to uncover correlations between vascularization degree and various factors.

Our population consists predominantly of females (53.68%), with a mean age of 45.85 ± 13.65 years. Only one mortality was recorded (7.7%). Pre-operative embolization achieved devascularization in the majority (69.2%) of cases, with approximately two-thirds (66.7%) experiencing complete devascularization. Mean total operative time stood at 336.11 ± 301.88 minutes, with a mean post-operative blood loss of 985.56 ± 1013.72 milliliters. Additionally, for those with recorded recovery times, the mean recovery time was 14.32 ± 13.51 hours.

Mortality rates showed no association with sex, devascularization status, or number of feeding vessel zones. Furthermore, the extent of devascularization did not correlate with age, sex, number of feeding vessel zones, postoperative blood loss, total operative time, or recovery time (p >0.05).

In summary, this study represents a significant endeavor to elucidate factors influencing meningioma outcomes following pre-operative embolization. Despite limitations regarding patient numbers, our study offers valuable insights into operative parameters and embolization considerations for future analyses in our tertiary center.

Gliomas are the most common primary neuroepithelial tumors of the central nervous system in adults, of which glioblastoma is the deadliest subtype. Apart from the intrinsically indestructible characteristics of glioma (stem) cells, accumulating evidence suggests that the tumor microenvironment also plays a vital role in the refractoriness of glioblastoma. The primary functions of platelets are to stop bleeding and regulate thrombosis under physiological conditions. Furthermore, platelets are also active elements that participate in a variety of processes of tumor development, including tumor growth, invasion, and chemoresistance. Glioma cells recruit and activate resting platelets to become tumor-educated platelets (TEPs), which in turn can promote the proliferation, invasion, stemness, and chemoresistance of glioma cells. TEPs can be used to obtain genetic information about gliomas, which is helpful for early diagnosis and monitoring of therapeutic effects. Platelet membranes are intriguing biomimetic materials for developing efficacious drug carriers to enhance antiglioma activity. Herein, we review the recent research referring to the contribution of platelets to the malignant characteristics of gliomas and focusing on the molecular mechanisms mediating the interaction between TEPs and glioma (stem) cells, as well as present the challenges and opportunities in targeting platelets for glioma therapy.
Humans ; Glioma/metabolism* ; Blood Platelets/physiology* ; Brain Neoplasms/pathology* ; Tumor Microenvironment

Brain cancer remains among the most lethal malignancies worldwide, with approximately 321,476 new cases and 248,305 deaths reported globally in 2022. The treatment of malignant brain tumors presents substantial clinical challenges, primarily due to their resistance to standard therapeutic approaches. Despite decades of intensive research, effective treatment strategies for brain cancer are still lacking. Nuclear receptors (NRs), a superfamily of ligand-activated transcription factors, regulate a broad range of physiological processes including metabolism, immunity, stress response, reproduction, and cellular differentiation. Increasing evidence highlights the involvement of NRs in oncogenesis, with several members demonstrating altered expression and function in brain tumors. Aberrations in NR signaling, encompassing receptors such as androgen receptors, estrogen receptors, estrogen-related receptors, glucocorticoid receptors, NR subfamily 4 group A, NR subfamily 1 group D member 2, NR subfamily 5 group A member 2, NR subfamily 2 group C member 2, liver X receptors, peroxisome-proliferator activated receptors, progesterone receptors, retinoic acid receptors, NR subfamily 2 group E member 1, thyroid hormone receptors, vitamin D receptors, and retinoid X receptors, have been implicated in promoting hallmark malignant phenotypes, including enhanced survival, proliferation, invasion, migration, metastasis, and resistance to therapy. This review aims to explore the roles of key NRs in brain cancer, with an emphasis on their prognostic significance, and to evaluate the therapeutic potential of targeting these receptors using selective agonists or antagonists.
Humans ; Brain Neoplasms/drug therapy* ; Receptors, Cytoplasmic and Nuclear/metabolism* ; Animals ; Signal Transduction/physiology*