OBJECTIVES: To evaluate the efficacy of molecular targeted agents in children with progressive pediatric low-grade gliomas (pLGG). METHODS: A retrospective analysis was conducted on pLGG patients treated with oral targeted therapies at the Department of Pediatrics, Beijing Shijitan Hospital, Capital Medical University, from July 2021. Treatment responses and safety profiles were assessed. RESULTS: Among the 20 enrolled patients, the trametinib group (n=12, including 11 cases with BRAF fusions and 1 case with BRAF V600E mutation) demonstrated 4 partial responses (33%) and 2 minor responses (17%), with a median time to response of 3.0 months. In the vemurafenib group (n=6, all with BRAF V600E mutation), 5 patients achieved partial responses (83%), showing a median time to response of 1.0 month. Comparative analysis revealed no statistically significant difference in progression-free survival rates between the two treatment groups (P>0.05). The median duration of clinical benefit (defined as partial response + minor response + stable disease) was 11.0 months for vemurafenib and 18.0 months for trametinib. Two additional cases, one with ATM mutation treated with olaparib for 24 months and one with NF1 mutation receiving everolimus for 21 months, discontinued treatment due to sustained disease stability. No severe adverse events were observed in any treatment group. CONCLUSIONS Molecular targeted therapy demonstrates clinical efficacy with favorable tolerability in pLGG. Vemurafenib achieves high response rates and induces early tumor shrinkage in patients with BRAF V600E mutations, supporting its utility as a first-line therapy.
Humans ; Glioma/genetics* ; Male ; Female ; Child ; Child, Preschool ; Retrospective Studies ; Brain Neoplasms/genetics* ; Molecular Targeted Therapy/adverse effects* ; Adolescent ; Infant ; Proto-Oncogene Proteins B-raf/genetics* ; Pyrimidinones/therapeutic use* ; Mutation

OBJECTIVE

To present a long-term follow-up report of a 10-year-old male with optic nerve glioma who underwent surgical removal and postoperative chemotherapy.

Case report.

A 10-year-old Filipino boy was referred to a tertiary institution for a five-year history of progressive right eye proptosis with vision loss. Pertinent findings included right eye proptosis, lagophthalmos, and limited elevation and adduction. He also had several hyperpigmented lesions on the abdomen and upper torso. Vision on the right was no light perception, with a relative afferent pupillary defect, exposure keratopathy, and optic nerve pallor. Vision on the left eye was 20/20 with a temporal visual field defect. Cranial and orbital computed tomography (CT) scan showed a circumscribed enhancing mass within the right intraconal space with widened right optic nerve canal. Additional magnetic resonance imaging (MRI) revealed a heterogeneously enhancing mass diffusely involving the intraorbital and intracanalicular segments of the right optic nerve suspicious for optic nerve glioma. He underwent excision of the orbital portion of the mass via lateral orbitotomy. Histopathology showed pilocytic astrocytoma. Eight cycles of chemotherapy with carboplatin and vincristine was completed. Significant improvement of globe position and resolution of ocular exposure was achieved postoperatively with residual right ptosis. These findings remained stable at six years after treatment.

Optic nerve gliomas with intracanalicular and chiasmal extension can be managed with surgical removal of the orbital component and postoperative chemotherapy. This can result in improvement of proptosis and long-term remission.

Isocitrate dehydrogenase (IDH) is an essential metabolic enzyme in the tricarboxylic acid cycle (TAC). The high mutation frequency of the IDH gene plays a complicated role in gliomas. In addition to affecting gliomas directly, mutations in IDH can also alter their immune microenvironment and can change immune-cell function in direct and indirect ways. IDH mutations mediate immune-cell infiltration and function by modulating immune-checkpoint gene expression and chemokine secretion. In addition, IDH mutation-derived D2-hydroxyglutarate can be absorbed by surrounding immune cells, also affecting their functioning. In this review, we summarize current knowledge about the effects of IDH mutations as well as other gene mutations on the immune microenvironment of gliomas. We also describe recent preclinical and clinical data related to IDH-mutant inhibitors for the treatment of gliomas. Finally, we discuss different types of immunotherapy and the immunotherapeutic potential of IDH mutations in gliomas.
Brain Neoplasms/therapy* ; Glioma/therapy* ; Humans ; Immunotherapy ; Isocitrate Dehydrogenase/genetics* ; Mutation/genetics* ; Tumor Microenvironment

OBJECTIVES: Glioma is the most common primary intracranial tumor and there is still no ideal treatment at present. Gene therapy, as one of the new methods for treating glioma, has attracted attention in recent years. But its application in treating glioma is very limited due to lack of effective delivery vectors. This study aims to investigate the feasibility of biomimetic nanomaterials made from glioma cells-derived extracellular vesicles (EV) for targeted delivery of signal transducers and activators of transcription 3 (STAT3)-small interfering RNA (siRNA) in treating glioma. METHODS: First, U251 glioma cells-derived extracellular vessel (EVU251) was extracted by ultra-centrifugal method. Nanoparticle tracking analysis was used to characterize the particle size distribution, the transmission electron microscope was used to analyze the morphology, and Western blotting was used to verify the expression of srface characteristic protein. The homing ability was verified by cell uptake assay after labeling EVU251 with membrane dye kit PKH67; the EVU251 contents were removed by a low permeability method and then EVMU251 was prepared through a microporous membrane. Finally, the biomimetic nanomaterials EVMU251@STAT3-siRNA were prepared by loading STAT3-SiRNA with electro-dyeing method. The real-time quantitative PCR was used to quantify the successful encapsulation of siRNA, and the encapsulation and drug loading rate was calculated; then Cy5-labeled siRNA was used to evaluate the ability of biomimetic nanomaterials (EVMU251@CY5-siRNA) to target U251 cells. Lysosomal escape ability of the biomimetic nanomaterial was evaluated by lysosomal dye lyso-tracker green. At last, the ability of EVMU251@STAT3-siRNA to knock down STAT3 gene and selective killing of U251 cells was detected by cell experiments in vitro. RESULTS: The size of EVU251 ranged from 50 nm to 200 nm with a natural disc shape. The expression of extracellular vesicle marker proteins could be detected on the membrane of EVU251. The cell uptake assay demonstrated that it had homing ability to target U251 cells. After EVU251 was prepared as EVMU251@STAT3-siRNA, the particle size was (177.9±5.0) nm, the siRNA loading rate was (33.5±2.2)% and the drug loading rate was (3.24±0.21)%. The biomimetic nanomaterial EVMU251@STAT3-siRNA still had the ability to target U251 cells and successfully deliver siRNA to the cytoplasm without lysosomal degradation. The EVMU251@STAT3-siRNA can effectively knock down the expression of STAT3 gene and produce selective killing ability in U251 cells. CONCLUSIONS The biomimetic nanomaterials EVMU251@STAT3-siRNA made from glioma U251 cells-derived extracellular vesicles can knock down STAT3 gene of U251 cells and produce selective killing effect, which can provide a new idea for the treatment of glioma.
Humans ; RNA, Small Interfering/genetics* ; Biomimetics ; Cell Line, Tumor ; Glioma/therapy* ; Nanostructures ; Cell Proliferation ; STAT3 Transcription Factor/metabolism*

Glioma is the most common lethal tumor of the human brain. The median survival of patients with primary World Health Organization grade IV glioma is only 14.6 months. The World Health Organization classification of tumors of the central nervous system categorized gliomas into lower-grade gliomas and glioblastomas. Unlike primary glioblastoma that usually develop de novo in the elderly, secondary glioblastoma enriched with an isocitrate dehydrogenase mutant typically progresses from lower-grade glioma within 5-10 years from the time of diagnosis. Based on various evolutional trajectories brought on by clonal and subclonal alterations, the evolution patterns of glioma vary according to different theories. Some important features distinguish the normal brain from other tissues, e.g., the composition of the microenvironment around the tumor cells, the presence of the blood-brain barrier, and others. The underlying mechanism of glioma recurrence and evolution patterns of glioma are different from those of other types of cancer. Several studies correlated tumor recurrence with tumor heterogeneity and the immune microenvironment. However, the detailed reasons for the progression and recurrence of glioma remain controversial. In this review, we introduce the different mechanisms involved in glioma progression, including tumor heterogeneity, the tumor microenvironment and drug resistance, and their pre-clinical implements in clinical trials. This review aimed to provide new insights into further clinical strategies for the treatment of patients with recurrent and secondary glioma.
Aged ; Brain Neoplasms/genetics* ; Drug Resistance ; Glioblastoma ; Glioma/genetics* ; Humans ; Mutation ; Neoplasm Recurrence, Local/drug therapy* ; Tumor Microenvironment

OBJECTIVE: To establish a mouse model bearing orthotopic temozolomide (TMZ)-resistant glioma that mimics the development of drug resistance in gliomas METHODS: Seventy-eight adult C57BL/6 mice were randomly divided into 6 groups ( RESULTS: The mouse models bearing TMZresistant glioma was successfully established. The cells from the high-dose induced group showed a significantly higher colony-forming rate than those from the high-dose control group ( CONCLUSIONS Progressive increase of TMZ doses in mice bearing orthotopic gliomas can effectively induce TMZ resistance of the gliomas.
Animals ; Antineoplastic Agents, Alkylating/pharmacology* ; Brain Neoplasms/drug therapy* ; Cell Line, Tumor ; Disease Models, Animal ; Drug Resistance, Neoplasm ; Glioma/drug therapy* ; Mice ; Mice, Inbred C57BL ; Temozolomide/therapeutic use*

Brain tumors are the second most common type of structural brain lesion that causes chronic epilepsy. Patients with low-grade brain tumors often experience chronic drug-resistant epilepsy starting in childhood, which led to the concept of long-term epilepsy-associated tumors (LEATs). Dysembryoplastic neuroepithelial tumor and ganglioglioma are representative LEATs and are characterized by young age of onset, frequent temporal lobe location, benign tumor biology, and chronic epilepsy. Although highly relevant in clinical epileptology, the concept of LEATs has been criticized in the neuro-oncology field. Recent genomic and molecular studies have challenged traditional views on LEATs and low-grade gliomas. Molecular studies have revealed that low-grade gliomas can largely be divided into three groups : LEATs, pediatric-type diffuse low-grade glioma (DLGG; astrocytoma and oligodendroglioma), and adult-type DLGG. There is substantial overlap between conventional LEATs and pediatric-type DLGG in regard to clinical features, histology, and molecular characteristics. LEATs and pediatric-type DLGG are characterized by mutations in BRAF, FGFR1, and MYB/MYBL1, which converge on the RAS-RAF-MAPK pathway. Gene (mutation)-centered classification of epilepsy-associated tumors could provide new insight into these heterogeneous and diverse neoplasms and may lead to novel molecular targeted therapies for epilepsy in the near future.
Age of Onset ; Astrocytoma ; Biology ; Brain ; Brain Neoplasms ; Classification ; Epilepsy ; Ganglioglioma ; Glioma ; Humans ; Molecular Targeted Therapy ; Neoplasms, Neuroepithelial ; Seizures ; Temporal Lobe

Glioma is the most common brain tumor with a dismal prognosis. While temozolomide (TMZ) based chemotherapy significantly improves survival in glioma patients, resistance against this compound commonly leads to glioma treatment failure. Overexpression of long-noncoding RNA (LncRNA) FoxD2 adjacent opposite strand RNA 1 (FoxD2-AS1) was identified to promote glioma development, but the role in TMZ resistance remains unclear. In this paper, we found that FoxD2-AS1 was overexpressed in recurrent glioma, high FoxD2-AS1 expression was significantly correlated with poor patient outcome. Methylation of O⁶-methylguanine-DNA methyltransferase (MGMT) is significantly less frequent in high FoxD2-AS1 expression patients. Knockdown of FoxD2-AS1 decreased the proliferation, metastatic ability of glioma cells and promote the sensitivity to TMZ in glioma cells. Furthermore, knockdown of FoxD2-AS1 induced hypermethylation of the promoter region of MGMT. Our data suggested that FoxD2-AS1 is a clinical relevance LncRNA and mediates TMZ resistance by regulating the methylation status of the MGMT promoter region.
Brain Neoplasms ; Drug Resistance ; Drug Therapy ; Glioma ; Humans ; Methylation ; Prognosis ; Promoter Regions, Genetic ; RNA ; RNA, Long Noncoding ; Treatment Failure

Bilateral thalamic gliomas (BTGs) are rare brain tumors. In general, the prognosis is poor because of the involvement of bilateral thalami and limitations of surgical excision. Consequently, patients with symptoms of personality changes and memory impairment must be differentiated from others. Magnetic resonance imaging (MRI) is essential for the diagnosis of BTGs and reveals a hypo-intense lesion on T1-weighted images and a hyper-intense lesion on T2 images. We report a case of a 17-year-old female patient suffering from progressive cognitive dysfunction and personality changes and subsequent rehabilitation treatment. Brain MRI showed an enlarged bilateral thalamus, with hyperintensity on T2-weighted images and iso-intensity on T1-weighted images. A biopsy was performed, and the pathology revealed a high-grade glioma. The patient was referred for radiotherapy and chemotherapy. She also underwent rehabilitation treatment for 5 weeks and showed improvement in standing balance, endurance, and speech fluency. The patient's Modified Barthel Index scores also improved. Cancer rehabilitation is important in brain tumor patients because they have a higher incidence of neurological sequelae than others. Rehabilitation of patients with a malignant brain tumor is also important for improving health-related quality of life by maintaining the general condition and preventing complications during and after cancer treatment.
Adolescent ; Biopsy ; Brain ; Brain Neoplasms ; Diagnosis ; Drug Therapy ; Female ; Glioma ; Humans ; Incidence ; Magnetic Resonance Imaging ; Memory ; Memory Disorders ; Neurobehavioral Manifestations ; Pathology ; Prognosis ; Quality of Life ; Radiotherapy ; Rehabilitation ; Thalamus

BACKGROUND: Pilocytic astrocytoma (PA) is a brain tumor that is relatively more common in children and young adults. METHODS: We retrospectively reviewed the medical records of patients with PA treated at a single center between 1988 and 2018. RESULTS: We included 31 subjects with PA. The median age at diagnosis was 13.4 years, and the median follow-up duration was 9.9 years. The total PA group had a 10-year disease-specific survival (DSS) rate of 92.6% [95% confidence interval (CI), 82.6–100] and 10-year progression-free survival (PFS) rate of 52.8% (95% CI, 32.0–73.6). In patients aged <20 years, tumors were more likely to be located in sites in which gross total tumor resection (GTR) was impossible. No statistically significant difference in 10-year DSS was found between the GTR (100%) and non-GTR (89.7%; 95% CI, 76.2–100; p=0.374) groups. However, a statistically significant difference in 10-year PFS was found between the GTR (100%) and non-GTR groups (30.7%; 95% CI, 8.6–52.8; p=0.012). In the non-GTR group, no statistically significant difference in 10-year DSS was found between the patients who received immediate additional chemotherapy and/or radiotherapy (Add-Tx group, 92.9%; 95% CI, 79.4–100) and the non-Add-Tx group (83.3%; 95% CI, 53.5–100; p=0.577). No statistically significant difference in 10-year PFS was found between the Add-Tx group (28.9%; 95% CI, 1.7–56.1) and non-Add-Tx group (33.3%; 95% CI, 0–70.9; p=0.706). CONCLUSION: The PFS of the patients with PA in our study depended only on the degree of surgical excision associated with tumor location. This study is limited by its small number of patients and retrospective nature. A multicenter and prospective study is necessary to confirm these findings.
Adolescent ; Astrocytoma ; Brain Neoplasms ; Child ; Diagnosis ; Disease-Free Survival ; Drug Therapy ; Follow-Up Studies ; Glioma ; Humans ; Medical Records ; Prognosis ; Prospective Studies ; Radiotherapy ; Retrospective Studies ; Survivors ; Young Adult