The brain tumor microenvironment (TME) plays a critical role in the progression and treatment response of various brain malignancies. Friebel et al. conducted a single-cell analysis revealing that the TME is shaped by both the central nervous system (CNS) milieu and the tumor itself, particularly highlighting the role of tumor-associated macrophages (TAMs) in gliomas and metastases (ref: Friebel doi.org/10.1016/j.cell.2020.04.055/). Klemm et al. expanded on this by employing flow cytometry and RNA sequencing to demonstrate that the immune landscape of brain tumors varies significantly between primary gliomas and metastatic brain tumors, suggesting that distinct immune cell populations may be targeted for therapeutic interventions (ref: Klemm doi.org/10.1016/j.cell.2020.05.007/). Additionally, the study by Michealraj et al. on infantile ependymomas revealed that these tumors are maintained under hypoxic conditions, which promote epigenetic changes that drive tumor aggressiveness, further complicating the TME's role in tumor biology (ref: Michealraj doi.org/10.1016/j.cell.2020.04.047/). The characterization of the tumor microbiome by Nejman et al. also adds a novel dimension, indicating that different tumor types harbor unique microbiomes, which could influence tumor behavior and immune responses (ref: Nejman doi.org/10.1126/science.aay9189/). Buccarelli et al. highlighted the deregulated expression of the DLK1-DIO3 region in glioblastoma stem-like cells, suggesting a potential tumor suppressor role for lncRNA MEG3, which could be pivotal in understanding the molecular underpinnings of glioblastoma aggressiveness (ref: Buccarelli doi.org/10.1093/neuonc/). Di Stefano et al. focused on FGFR3-TACC3 fusions in gliomas, revealing their clinical significance and potential as therapeutic targets, thereby linking molecular alterations to immune landscape changes (ref: Di Stefano doi.org/10.1093/neuonc/).

Recent advancements in neurosurgical techniques have focused on improving precision and patient outcomes. Rynes et al. introduced an open-source, computer numerical controlled (CNC) robot designed for cranial microsurgical procedures, which enhances the accuracy of surgical interventions and allows for the deployment of neural probes (ref: Rynes doi.org/10.1038/s41596-020-0318-4/). This innovation is crucial as the complexity of neurosurgical procedures increases with the advent of new technologies. In a different approach, Hu et al. demonstrated that extracellular vesicles derived from embryonic stem cells can rejuvenate senescent hippocampal neural stem cells, potentially reversing cognitive dysfunction in vascular dementia, thus highlighting a novel therapeutic avenue for cognitive disorders (ref: Hu doi.org/10.1002/advs.201903330/). The development of a biomimetic plasmonic nanoreactor by Liu et al. for metabolite detection represents another significant innovation, offering reliable monitoring of metabolites critical for disease management (ref: Liu doi.org/10.1002/advs.201903730/). Furthermore, the study by Ng et al. on DNAJC6 mutations in juvenile parkinsonism underscores the importance of genetic insights in refining neurosurgical approaches for movement disorders (ref: Ng doi.org/10.1002/mds.28063/). Craig et al. investigated the microstructure of the pedunculopontine nucleus, revealing its predictive value for postural and gait symptoms in Parkinson's disease, which could inform surgical interventions aimed at alleviating these symptoms (ref: Craig doi.org/10.1002/mds.28051/).

Neurodegenerative diseases and cognitive disorders continue to be a significant focus of research, with studies revealing critical insights into their underlying mechanisms. Di Stefano et al. characterized the clinical and molecular profiles of gliomas with FGFR3-TACC3 fusions, emphasizing the need for targeted therapies in this subset of tumors (ref: Di Stefano doi.org/10.1093/neuonc/). Goyal et al. explored the role of theta oscillations in the human hippocampus, providing evidence for distinct oscillatory patterns that may influence memory and navigation, thus linking neural activity to cognitive function (ref: Goyal doi.org/10.1038/s41467-020-15670-6/). The identification of somatic mutations in prolactinomas by Li et al. highlights the genetic basis of these tumors, which could inform treatment strategies (ref: Li doi.org/10.1038/s41467-020-16052-8/). Veys et al. investigated the GLUT1 glucose transporter, revealing its critical role in CNS angiogenesis and blood-brain barrier integrity, which is essential for maintaining cognitive function (ref: Veys doi.org/10.1161/CIRCRESAHA.119.316463/). Arena et al. provided insights into tau pathology in chronic traumatic encephalopathy, linking it to aging and Alzheimer's disease, thereby enhancing our understanding of neurodegenerative processes (ref: Arena doi.org/10.1093/brain/). The phase II study by Goldman et al. on peginterferon alpha-2b for craniopharyngiomas demonstrated the potential for novel therapeutic approaches in pediatric brain tumors, emphasizing the need for continued exploration of treatment efficacy (ref: Goldman doi.org/10.1093/neuonc/).

Stroke and vascular neurology research has revealed critical findings regarding treatment efficacy and patient outcomes. Yang et al. conducted a study comparing endovascular thrombectomy alone versus thrombectomy with intravenous alteplase in acute ischemic stroke patients, finding that thrombectomy alone was noninferior in terms of functional outcomes, which could influence treatment protocols (ref: Yang doi.org/10.1056/NEJMoa2001123/). Teo et al. reported significant delays in stroke onset to hospital arrival times during the COVID-19 pandemic, highlighting the urgent need for strategies to mitigate these delays and improve patient care (ref: Teo doi.org/10.1161/STROKEAHA.120.030105/). Zhao et al. further emphasized the impact of COVID-19 on stroke care, noting a 26.7% drop in thrombolysis and thrombectomy cases, which raises concerns about access to timely treatment during health crises (ref: Zhao doi.org/10.1161/STROKEAHA.120.030225/). Saha et al. explored the antagonistic effects of temozolomide on oncolytic immunovirotherapy in glioblastoma, suggesting that standard treatments may interfere with emerging therapies (ref: Saha doi.org/10.1136/jitc-2019-000345/). Zhang et al. developed a novel nanoparticle delivery system for treating breast cancer brain metastases, addressing the challenge of crossing the blood-brain barrier, which is crucial for effective treatment (ref: Zhang doi.org/10.1002/adfm.201910651/).

Deep brain stimulation (DBS) and neuromodulation techniques have shown promising results in treating various neurological disorders. Vitek et al. conducted a multicenter, double-blind, randomized controlled trial on subthalamic nucleus DBS using a novel multiple independent constant current-controlled device, demonstrating its safety and efficacy in alleviating motor symptoms of Parkinson's disease (ref: Vitek doi.org/10.1016/S1474-4422(20)30108-3/). Saha et al. also highlighted the interaction between temozolomide and immunovirotherapy in glioblastoma, indicating that understanding these interactions is vital for optimizing treatment strategies (ref: Saha doi.org/10.1136/jitc-2019-000345/). Petzold et al. identified peripapillary hyper-reflective ovoid masslike structures in multiple sclerosis patients, suggesting a novel pathological pathway that could inform future neuromodulation strategies (ref: Petzold doi.org/10.1002/ana.25782/). Craig et al. investigated the microstructure of the pedunculopontine nucleus, linking its integrity to postural and gait symptoms in Parkinson's disease, which could enhance the precision of DBS interventions (ref: Craig doi.org/10.1002/mds.28051/). Zhang et al.'s work on brain tumor-targeting nanoparticles further underscores the importance of innovative delivery systems in enhancing treatment efficacy for brain metastases (ref: Zhang doi.org/10.1002/adfm.201910651/).

Research in neuroinflammation and neuroprotection has highlighted the complex interplay between immune responses and neurological health. Peng et al. investigated the role of the stimulator of IFN genes (STING) in neuroinflammatory injury following subarachnoid hemorrhage, revealing its potential as a therapeutic target to mitigate neuroinflammation (ref: Peng doi.org/10.1186/s12974-020-01830-4/). Kipnis et al. explored the efficacy of TrkB agonists in preventing postischemic neonatal seizures, suggesting that targeting neurotrophic pathways may offer new treatment avenues for refractory seizures (ref: Kipnis doi.org/10.1172/jci.insight.136007/). Yuan et al. demonstrated that inhibiting microglial activation in the amygdala can reverse stress-induced abdominal pain, indicating the importance of neuroinflammatory processes in pain modulation (ref: Yuan doi.org/10.1016/j.jcmgh.2020.04.020/). Krom et al. examined the effects of anesthesia on auditory processing, providing insights into how neuroinflammation may disrupt sensory processing during loss of consciousness (ref: Krom doi.org/10.1073/pnas.1917251117/). Chen et al. highlighted the role of isocitrate dehydrogenase 2 in radiation resistance, linking mitochondrial function and oxidative stress to neuroprotection in cancer therapy (ref: Chen doi.org/10.1038/s41416-020-0852-4/).

Ensuring patient safety and improving outcomes in neurosurgery are paramount concerns in the field. Storesund et al. conducted a nonrandomized clinical trial assessing the impact of combining the preoperative and postoperative SURPASS checklists with the WHO surgical safety checklist, finding a significant reduction in complications and readmissions, thereby underscoring the importance of structured protocols in enhancing surgical outcomes (ref: Storesund doi.org/10.1001/jamasurg.2020.0989/). Hu et al. demonstrated that extracellular vesicles can rejuvenate senescent neural stem cells, potentially reversing cognitive dysfunction in vascular dementia, which could have implications for postoperative cognitive care (ref: Hu doi.org/10.1002/advs.201903330/). Horowitz et al. developed a microfluidic platform for multiplexed drug testing of tumor slices, which could facilitate personalized medicine approaches in neurosurgery by allowing for rapid assessment of drug responses in patient-derived tissues (ref: Horowitz doi.org/10.1038/s41698-020-0117-y/). Kirchgessner et al. explored the dynamic functional influence of corticothalamic pathways, providing insights into how sensory processing can be optimized during neurosurgical procedures (ref: Kirchgessner doi.org/10.1073/pnas.2002080117/). These studies collectively emphasize the need for innovative approaches and protocols to enhance patient safety and surgical outcomes in neurosurgery.

Understanding the molecular mechanisms underlying neurosurgical conditions is crucial for advancing treatment strategies. Surface et al. discussed the implications of nitrogen-containing bisphosphonates in bone health, highlighting the need for careful consideration of their side effects in neurosurgical patients (ref: Surface doi.org/10.1126/scitranslmed.aav9166/). Kim et al. investigated the mechanism of microRNA arm switching, revealing how this process is regulated by uridylation and its potential implications for gene expression in neurological contexts (ref: Kim doi.org/10.1016/j.molcel.2020.04.030/). Di Stefano et al. characterized gliomas with FGFR3-TACC3 fusions, providing insights into the molecular profiles that could inform targeted therapies (ref: Di Stefano doi.org/10.1093/neuonc/). Michealraj et al. focused on the metabolic regulation of the epigenome in infantile ependymomas, suggesting that understanding these mechanisms could lead to novel therapeutic strategies (ref: Michealraj doi.org/10.1016/j.cell.2020.04.047/). Friebel et al. further elucidated the role of the TME in shaping immune responses in brain tumors, emphasizing the need for a comprehensive understanding of molecular interactions in neurosurgery (ref: Friebel doi.org/10.1016/j.cell.2020.04.055/).