Radiomic prediction for durable response to high-dose methotrexate-based chemotherapy in primary central nervous system lymphoma.

BACKGROUND: The rarity of primary central nervous system lymphoma (PCNSL) and treatment heterogeneity contributes to a lack of prognostic models for evaluating posttreatment remission. This study aimed to develop and validate radiomic-based models to predict the durable response (DR) to high-dose methotrexate (HD-MTX)-based chemotherapy in PCNSL patients. METHODS: A total of 159 patients pathologically diagnosed with PCNSL between 2011 and 2021 across two institutions were enrolled. According to the NCCN guidelines, the DR was defined as the remission lasting ≥1 year after receiving HD-MTX-based chemotherapy. For each patient, a total of 1218 radiomic features were extracted from prebiopsy T1 contrast-enhanced MR images. Multiple machine-learning algorithms were utilized for feature selection and classification to build a radiomic signature. The radiomic-clinical integrated models were developed using the random forest method. Model performance was externally validated to verify its clinical utility. RESULTS: A total of 105 PCNSL patients were enrolled after excluding 54 cases with ineligibility. The training and validation cohorts comprised 76 and 29 individuals, respectively. Among them, 65 patients achieved DR. The radiomic signature, consisting of 8 selected features, demonstrated strong predictive performance, with area under the curves of 0.994 in training cohort and 0.913 in validation cohort. This signature was independently associated with the DR in both cohorts. Both the radiomic signature and integrated models significantly outperformed the clinical models in two cohorts. Decision curve analysis underscored the clinical utility of the established models. CONCLUSIONS: This radiomic signature and integrated models have the potential to accurately predict the DR to HD-MTX-based chemotherapy in PCNSL patients, providing valuable therapeutic insights.

A longitudinal multimodal MRI study of the visual network in postoperative delirium.

Although structural and functional damage to the brain is considered to be an important neurobiological mechanism of postoperative delirium (POD), alterations in the visual cortical network related to this vulnerability have not yet been determined. In this study, we investigated the impact of alterations in the visual network (VN), as measured by structural and functional magnetic resonance imaging (MRI), on the development of POD. Thirty-six adult patients with frontal glioma who underwent elective craniotomy were recruited. The primary outcome was POD 1-7 days after surgery, as assessed by the Confusion Assessment Method. Cognition before surgery was measured by a battery of neuropsychological tests. Then, we evaluated preoperative and postoperative gray matter volume (GMV) and functional connectivity (FC) alterations by voxel-based morphometry and resting-state functional MRI (rs-fMRI) between the POD and non-POD groups. Multiple logistic regression models were used to investigate the associations between neuroimaging biomarkers and the occurrence of POD. Compared to those in the non-POD group, a decreased GMV in the fusiform gyrus (0.181 [0.018] vs. 0.207 [0.022], FDRp = 0.001) and decreased FC between the fusiform gyrus and VN (0.351 [0.153] vs. 0.610 [0.197], GFRp < 0.001) were observed preoperatively in the POD group, and increased FC between the fusiform gyrus and ventral attentional network (0.538 [0.180] vs. 0.452 [0.184], GFRp = < 0.001) was observed postoperatively in the POD group. According to our multiple logistic regression analysis, age (Odds ratio [OR]: 1.141 [1.015 to 1.282], P = 0.03) and preoperative fusiform-VN FC (OR 0.001 [0.001 to 0.067], P = 0.01) were significantly related to risk of POD. Our findings suggested that preoperative functional disconnectivity between fusiform and VN might be highly involved in the development of POD. These findings may allow for the discovery of additional underlying mechanisms.

Dihydromyricetin protects sevoflurane-induced mitochondrial dysfunction in HT22 hippocampal cells.

Sevoflurane (Sev) is a commonly used inhalation anaesthetic that has been shown to cause hippocampus dysfunction through multiple underlying molecular processes, including mitochondrial malfunction, oxidative stress and inflammation. Dihydromyricetin (DHM) is a 2,3-dihydroflavonoid with various biological properties, such as anti-inflammation and anti-oxidative stress. The purpose of this study was to investigate the effect of DHM on Sev-induced neuronal dysfunction. HT22 cells were incubated with 10, 20 and 30 µM of DHM for 24 h, and then stimulated with 4% Sev for 6 h. The effects and mechanism of DHM on inflammation, oxidative stress and mitochondrial dysfunction were explored in Sev-induced HT22 cells by Cell Counting Kit-8, flow cytometry, enzyme-linked immunosorbent assay, reverse transcription-quantitative polymerase chain reaction, colorimetric detections, detection of the level of reactive oxygen species (ROS), mitochondrial ROS and mitochondrial membrane potential (MMP), immunofluorescence and western blotting. Our results showed that DHM increased Sev-induced cell viability of HT22 cells. Pretreatment with DHM attenuated apoptosis, inflammation, oxidative stress and mitochondrial dysfunction in Sev-elicited HT22 cells by remedying the abnormality of the indicators involved in these progresses, including apoptosis rate, the cleaved-caspase 3 expression, as well as the level of tumour necrosis factor α, interleukin (IL)-1ß, IL-6, malondialdehyde, superoxide dismutase, catalase, ROS, mitochondrial ROS and MMP. Mechanically, pretreatment with DHM restored the Sev-induced the expression of SIRT1/FOXO3a pathway in HT22 cells. Blocking of SIRT1 counteracted the mitigatory effect of DHM on apoptosis, inflammation, oxidative stress and mitochondrial dysfunction in Sev-elicited HT22 cells. Collectively, pretreatment with DHM improved inflammation, oxidative stress and mitochondrial dysfunction via SIRT1/FOXO3a pathway in Sev-induced HT22 cells.

Permeable Self-Association of Metal-Organic Framework 808/Ag-Based Fiber Membrane for Broad-Spectrum and Highly Efficient Degradation of Biological and Chemical War Agents.

The threat posed by biological and chemical warfare agents (BCWA) to national security, the environment, and personal health underscores the need for innovative chemical protective clothing. To address the limitations of conventional activated carbon materials, which are prone to falling off and adsorption saturation, an efficient self-association approach was introduced. In this study, we proposed the immobilization of metal-organic framework (MOF) 808 and Ag nanoparticles onto a polypropylene (PP) fiber membrane using a rapid self-association method facilitated by chitosan (CS). The MOF 808/Ag-based (PP-CS/808-Ag) fiber membrane demonstrated exceptional degradation efficiency, achieving a remarkable rate of t1/2 within 2 h for the mustard simulant 2-chloroethyl ethyl sulfide (2-CEES) and a rate of t1/2 = 4.12 min for the G-series simulant dimethyl 4-nitrophenylphosphate (DMNP). A theoretical computational model was developed to determine the overall reaction mechanism, and it was verified that MOF 808 and Ag nanoparticles were mainly involved in the hydrolysis process against 2-CEES and DMNP. The PP-CS/808-Ag composite fiber film was prepared as the core layer, and the fracture strength, bending resistance, and moisture permeability were better than those specified by many countries for biochemical protective clothing, showing that it has a broad application prospect in developing a generation of broad-spectrum bioprotective clothing.

TLR agonists promote formation of Tertiary Lymphoid Structure and improve anti-glioma immunity.

BACKGROUND: Glioma, characterized by limited lymphocytic infiltration, constitutes an "immune-desert" tumor displaying insensitivity to various immunotherapies. This study aims to explore therapeutic strategies for inducing tertiary lymphoid structure (TLS) formation within the glioma microenvironment (GME) to transition it from an immune-resistant to an activated state. METHODS: TLS formation in GME was successfully induced by intracranial administration of Toll-like receptor (TLR) agonists (OK-432, TLR2/4/9 agonist) and glioma antigens (i.c. αTLR-mix). We employed staining analysis, antibody neutralization, single-cell RNA sequencing (scRNA-Seq), and BCR/TCR sequencing to investigate the underlying mechanisms of TLS formation and its role in anti-glioma immunity. Additionally, a preliminary translational clinical study was conducted. RESULTS: TLS formation correlated with increased lymphocyte infiltration in GME and led to improved prognosis in glioma-bearing mice. In the study of TLS induction mechanisms, certain macrophages/microglia and Th17 displayed markers of "LTo" and "LTi" cells, respectively, interaction through LTα/ß-LTßR promoted TLS induction. Post-TLS formation, CD4+ and CD8+ T cells but not CD19+ B cells contributed to anti-glioma immunity. Comparative analysis of B/T cells between brain and lymph node showed that brain B/T cells unveiled switch from naïve to mature, some B cells highlighted an enrichment of CSR-associated genes, V gene usage and clonotype bias were observed. In related clinical studies, i.c. αTLR-mix treatment exhibited tolerability, and chemokines/cytokines assay provided preliminary evidence supporting TLS formation in GME. CONCLUSION: TLS induction in GME enhanced anti-glioma immunity, improved the immune microenvironment, and controlled glioma growth, suggesting potential therapeutic avenues for treating glioma in the future.

Occurrence and risk factors for post-stroke delirium: A systematic review and meta-analysis.

OBJECTIVES: Delirium is a significant health concern in acute stroke patients. We aim to systematically summarize existing evidence to conduct a meta-analysis to quantify the occurrence and risk factors for delirium after acute stroke. METHOD: PubMed, EMBASE and MEDLINE were searched from inception to Feb. 2023 for prospective observational studies that reported the incidence or prevalence of post-stroke delirium and/or evaluated potential risk factors. The search strategy was created using controlled vocabulary terms and text words for stroke and delirium. We performed a meta-analysis of the estimates for occurrence and risk factors using random-effects models. Meta-regression and subgroup meta-analyses were conducted to explore the sources of heterogeneity. Study quality and quality of evidence were assessed using the customized Newcastle-Ottawa Scale and GRADE, respectively. RESULTS: Forty-nine studies that enrolled 12383 patients were included. The pooled occurrence rate of post-stroke delirium was 24.4 % (95 %CI, 20.4 %-28.9 %, I2=96.2 %). The pooled occurrence of hyperactive, hypoactive, and mixed delirium was 8.5 %, 5.7 % and 5.0 %, respectively. Study location, delirium assessment method and stroke type independently affected the heterogeneity of the pooled estimate of delirium. Statistically significant risk factors were older age, low education level, cigarette smoking, alcohol drinking, atrial fibrillation, lower ADL level, higher pre-stroke mRS score, premorbid cognitive impairment or dementia, aphasia, total anterior circulation impairment, higher National Institute of Health Stroke Scale score and infection. CONCLUSIONS: Delirium affected 1 in 4 acute stroke patients, although reported rates may depend on assessment method and stroke type. Timely prevention, recognition and intervention require prioritizing patients with dominant risk factors.

Electro-elution-based purification of covalent DNA-protein cross-links.

Covalent DNA-protein cross-links (DPCs) are pervasive DNA lesions that challenge genome stability and can be induced by metabolic or chemotherapeutic cross-linking agents including reactive aldehydes, topoisomerase poisons and DNMT1 inhibitors. The purification of x-linked proteins (PxP), where DNA-cross-linked proteins are separated from soluble proteins via electro-elution, can be used to identify DPCs. Here we describe a versatile and sensitive strategy for PxP. Mammalian cells are collected following exposure to a DPC-inducing agent, embedded in low-melt agarose plugs and lysed under denaturing conditions. Following lysis, the soluble proteins are extracted from the agarose plug by electro-elution, while genomic DNA and cross-linked proteins are retained in the plug. The cross-linked proteins can then be analyzed by standard analytical techniques such as sodium dodecyl-sulfate-polyacrylamide gel electrophoresis followed by western blotting or fluorescent staining. Alternatively, quantitative mass spectrometry-based proteomics can be used for the unbiased identification of DPCs. The isolation and analysis of DPCs by PxP overcomes the limitations of alternative methods to analyze DPCs that rely on precipitation as the separating principle and can be performed by users trained in molecular or cell biology within 2-3 d. The protocol has been optimized to study DPC induction and repair in mammalian cells but may also be adapted to other sample types including bacteria, yeast and tissue samples.

Decitabine cytotoxicity is promoted by dCMP deaminase DCTD and mitigated by SUMO-dependent E3 ligase TOPORS.

The nucleoside analogue decitabine (or 5-aza-dC) is used to treat several haematological cancers. Upon its triphosphorylation and incorporation into DNA, 5-aza-dC induces covalent DNA methyltransferase 1 DNA-protein crosslinks (DNMT1-DPCs), leading to DNA hypomethylation. However, 5-aza-dC's clinical outcomes vary, and relapse is common. Using genome-scale CRISPR/Cas9 screens, we map factors determining 5-aza-dC sensitivity. Unexpectedly, we find that loss of the dCMP deaminase DCTD causes 5-aza-dC resistance, suggesting that 5-aza-dUMP generation is cytotoxic. Combining results from a subsequent genetic screen in DCTD-deficient cells with the identification of the DNMT1-DPC-proximal proteome, we uncover the ubiquitin and SUMO1 E3 ligase, TOPORS, as a new DPC repair factor. TOPORS is recruited to SUMOylated DNMT1-DPCs and promotes their degradation. Our study suggests that 5-aza-dC-induced DPCs cause cytotoxicity when DPC repair is compromised, while cytotoxicity in wild-type cells arises from perturbed nucleotide metabolism, potentially laying the foundations for future identification of predictive biomarkers for decitabine treatment.

Glioblastoma patients' survival and its relevant risk factors during the pre-COVID-19 and post-COVID-19 pandemic: real-world cohort study in the USA and China.

BACKGROUND: Although the COVID-19 pandemic has exerted potential impact on patients with glioblastomas (GBMs), it remains unclear whether the survival and its related risk factors of GBM patients would be altered or not during the period spanning from pre-COVID-19 to post-COVID-19 pandemic era. This study aimed to clarify the important issues above. METHODS: Two observational cohorts were utilized, including the nationwide American cohort from the Surveillance, Epidemiology, and End-Results (SEER) and the Chinese glioblastoma cohort (CGC) at our institution during 2018-2020. Demographics, tumour features, treatment regimens and clinical outcomes were collected. Cox regression model, competing risk model, and subgroup and sensitivity analysis were used to dynamically estimate the survival and its relevant risk factors over different diagnosis years from the pre-COVID-19 (2018 and 2019) to post-COVID-19 (2020) pandemic. Causal mediation analysis was further adopted to explore the potential relationship between risk factors and mortality. RESULTS: This study included 11321 GBM cases in SEER and 226 GBM patients in CGC, respectively. Instead of the diagnostic years of 2018-2020, the prognostic risk factors, such as advanced age, bilateral tumour and absence of comprehensive therapy (surgery combined with chemoradiotherapy), were identified to persistently affect GBM survival independently during the period from 2018 to 2020 in the SEER cohort (all P < 0.05). In CGC, lack of comprehensive therapy for GBM patients were restated as survival risk factors during the same timeframe. Causal mediation analysis showed that the effect of comprehensive therapy on all-cause mortality played a determinant role (direct effect value -0.227, 95% CI -0.248 to -0.207), which was partially mediated by age (9.11%) rather than tumour laterality. CONCLUSIONS: As the timeframe shifted from pre-COVID-19 to post-COVID-19 pandemic, survival of GBM patients remained stable, yet advanced age, bilateral tumours, and passive treatment continuingly impacted GBM survival. It is necessary to optimize the comprehensive treatment for GBM patients even in the post-pandemic era.

Mitochondrial Mechanisms in Temozolomide Resistance: Unraveling the Complex Interplay and Therapeutic Strategies in Glioblastoma.

Glioblastoma (GBM) is a highly aggressive and lethal brain tumor, with temozolomide (TMZ) being the standard chemotherapeutic agent for its treatment. However, TMZ resistance often develops, limiting its therapeutic efficacy and contributing to poor patient outcomes. Recent evidence highlights the crucial role of mitochondria in the development of TMZ resistance through various mechanisms, including alterations in reactive oxygen species (ROS) production, metabolic reprogramming, apoptosis regulation, biogenesis, dynamics, stress response, and mtDNA mutations. This review article aims to provide a comprehensive overview of the mitochondrial mechanisms involved in TMZ resistance and discuss potential therapeutic strategies targeting these mechanisms to overcome resistance in GBM. We explore the current state of clinical trials targeting mitochondria or related pathways in primary GBM or recurrent GBM, as well as the challenges and future perspectives in this field. Understanding the complex interplay between mitochondria and TMZ resistance will facilitate the development of more effective therapeutic strategies and ultimately improve the prognosis for GBM patients.

Intratumoral calcification: not only a diagnostic but also a prognostic indicator in oligodendrogliomas.

OBJECTIVE: Calcification is a hallmark characteristic of oligodendroglioma (ODG) that may be used as a diagnostic factor, but its prognostic implications remain unclear. This study aimed to investigate the features of calcified ODGs and to evaluate the differences in survival between patients with calcified and noncalcified ODGs. METHODS: We retrospectively reviewed the records of 305 consecutive patients who were diagnosed with IDH-mutant, 1p/19q codeleted ODG at our institution from July 2009 to August 2020. Patients with intratumoral calcification were identified. The clinical, radiologic, and molecular features of the patients in the calcified group and noncalcified group were recorded. Univariate and multivariate analyses were performed to identify prognostic factors. RESULTS: Of the 305 patients, 112 (36.7%) were confirmed to have intratumoral calcification. Compared to ODGs without calcification, ODGs with calcifications had a larger tumor diameter; lower degree of resection; higher tumor grade; higher MGMT methylation level; higher Ki-67 index; and higher rates of midline crossing, enhancement, cyst, and 1q/19p copolysomy, and patients with calcification were more likely to receive chemoradiotherapy. ODGs with T2 hypointense calcification had a higher Hounsfield unit (HU) value on CT scans, and a lower degree of resection. Patients with T2 hypointense calcification ODGs had a shorter survival than those with non-hypointense calcification ODGs. ODGs with calcification and cysts showed a higher Ki-67 index, tumor grade, and enhanced rate, and the patients had an unfavorable overall survival (OS). Calcification was found to be a negative prognostic factor for both progression-free survival (PFS) and OS by univariate analysis, which was confirmed by the Cox proportional hazard model. CONCLUSIONS: Calcification is a useful negative prognostic factor for PFS and OS in patients with ODGs and could therefore be helpful in guiding personalized treatment and predicting patient prognosis. CLINICAL RELEVANCE STATEMENT: Calcification can serve as an independent prognostic factor for patients with oligodendroglioma and shows a vital role in guiding individualized treatment. KEY POINTS: • Intratumoral calcification is an independent negative prognostic risk factor for progression-free survival and overall survival in oligodendroglioma patients. • Calcifications in oligodendroglioma can be divided into hypointense and non-hypointense subtypes based on T2-weighted imaging, and patients with T2-hypointense calcification oligodendrogliomas have worse prognosis. • Calcification concurrent with cysts indicates a more aggressive phenotype of oligodendrogliomas and a significantly reduced survival rate.

Laser-Triggered High Graphitization of Mo2C@C: High Rate Performance and Excellent Cycling Stability as Anode of Lithium Ion Batteries.

Fast electron/ion transport and cycling stability of anode materials are key factors for achieving a high rate performance of battery materials. Herein, we successfully fabricated a carbon-coated Mo2C nanofiber (denoted as laser Mo2C@C) as the lithium ion battery anode material by laser carbonization of PAN-PMo12 (PAN = Polyacrylonitrile; PMo12 = H3PMo12O40). The highly graphitized carbon layer in laser Mo2C@C effectively protects Mo2C from agglomeration and flaking while facilitating electron transfer. As such, the laser Mo2C@C electrode displays an excellent electrochemical stability under 5 A g-1, with a capacity up to 300 mA h g-1 after 3000 cycles. Furthermore, the extended X-ray absorption fine structure results show the existence of some Mo vacancies in Mo2C@C. Density functional theory calculations further prove that such vacancies make the defective Mo2C@C composites energetically more favorable for lithium storage in comparison with the intact Mo2C.

Characteristics Analysis of Plasticized Polyvinyl Chloride Gel-Based Microlens at Different Temperatures.

Temperature plays a crucial role in the preparation of polyvinyl chloride (PVC) gels for optical applications. Incorrect temperature selection can lead to various issues such as poor surface roughness, inadequate light transmission, and insufficient solution for optical devices. To address this challenge, this study focuses on the preparation of PVC gel samples by combining PVC powder (n = 3000), eco-friendly dibutyl adipate, and tetrahydrofuran at different stirring temperatures ranging from 40 to 70 °C. The PVC gel preparation process is categorized into four groups (T40, T50, T60, and T70) based on the mixing temperatures, employing a controlled test method with specific temperature conditions. The prepared PVC gel samples are then subjected to analysis to evaluate various properties including surface morphology, tensile strength, light transmittance, and electrical response time. Among the samples, the PVC gel prepared at 60 °C (referred to as T60) exhibits excellent optical properties, with a transmittance of 91.2% and a tensile strength of 2.07 MPa. These results indicate that 60 °C is an optimal reaction temperature. Notably, the PVC gel microlenses produced at this temperature achieve their maximum focal length (ranging from -8 to -20 mm) within approximately 60 s, and they recover their initial state within around 80 s after the power is switched off. This focal length achievement is twice as fast as reported in previous studies on microlenses. It is observed that the reaction temperature significantly influences the solubility of the resin-based raw materials and the homogeneity of the gel. Consequently, these findings open up possibilities for utilizing PVC gel microlenses in novel commercial optics applications, thanks to their desirable properties.

Is brain invasion sufficient as a stand-alone criterion for grading atypical meningioma?

OBJECTIVE: Despite the controversy surrounding brain invasion (BI) as the sole indicator used to diagnose atypical meningioma, this criterion was still incorporated in the 2021 WHO classification scheme. In this study, the authors investigated the reproducibility of this prognostic effect and the impact of BI on the prognosis in otherwise benign meningioma (benign meningioma with BI). METHODS: Patients (n = 1006) with a pathological diagnosis of benign or atypical meningioma according to the latest WHO classification criteria were enrolled in this study. In patients with atypical meningioma, the cases were further categorized as benign meningioma with BI and classical atypical meningioma. Clinical, pathological, and follow-up data were collected. Kaplan-Meier curves were compared with a log-rank test, and univariate and multivariate analyses were performed. RESULTS: The study patient cohort included 282 (28.0%) individuals who were pathologically confirmed as having BI among all 1006 patients with benign or atypical meningioma. A significant difference in recurrence-free survival was observed between patients who had benign meningioma with BI and those who had classical atypical meningioma (p < 0.001), as well as between patients with benign meningiomas and those without BI (p = 0.003). Multivariate Cox analysis indicated that BI was independently associated with increased risk of relapse in the entire population (HR 1.46, 95% CI 1.01-2.12, p = 0.049) and in the atypical meningioma subcohort (HR 2.21, 95% CI 1.32-3.71, p = 0.003), as well as the benign meningioma with and without BI subcohorts (HR 1.89, 95% CI 1.01-3.56, p = 0.049). Moreover, patients with classical atypical meningiomas had a risk of relapse four times higher than those who had benign meningioma with BI (p < 0.001). CONCLUSIONS: The findings demonstrate that benign meningioma with BI typically has an intermediate prognosis and can be differentiated from benign meningioma and classical atypical meningioma, which suggests that the importance of the diagnostic effect of BI is insufficiently accounted for in grading of atypical meningioma. Increased emphasis on the presence of BI in patients with atypical meningioma may be helpful in postsurgical decision-making and facilitating improvements in individual therapy.

Decision-making tree for surgical treatment in meningioma: a geriatric cohort study.

Controversies persist regarding the benefits of surgery in elderly patients with meningiomas. The objective of this study was to develop decision-making scale to clarify the necessity for surgical intervention and provide clinical consultation for this special population. This retrospective cohort study was conducted at a single center and included 478 elderly patients (≥ 65 years) who underwent meningioma resection. Follow-up was recorded to determine recurrence and mortality rates. Univariate and multivariate analyses were performed to identify significantly preoperative factors, and prognostic prediction models were developed with determined cutoff values for the prognostic index (PI). Model discrimination was evaluated using Kaplan-Meier curves based on the PI stratification, which categorized patients into low- and high-risk groups. A decision-making tree was then established based on the risk stratification from both models. Among all patients analyzed (n = 478), 62 (13.0%) experience recurrence and 47 (10.0%) died during the follow-up period. Significantly preoperative parameters from both models included advanced age, aCCI, recurrent tumor, motor cortex involvement, male sex, peritumoral edema, and tumor located in skull base (all P < 0.05). According to the classification of PI from the two models, the decision-making tree provided four recommendations that can be used for clinical consultation. Surgery is not recommended for patients assigned to the high-risk group in both models. Patients who meet the low-risk criteria in any model may undergo surgical intervention, but the final decision should depend on the surgeon's expertise.

Dysregulated lipid metabolism in TMZ-resistant glioblastoma: pathways, proteins, metabolites and therapeutic opportunities.

Glioblastoma (GBM) is a highly aggressive and lethal brain tumor with limited treatment options, such as the chemotherapeutic agent, temozolomide (TMZ). However, many GBM tumors develop resistance to TMZ, which is a major obstacle to effective therapy. Recently, dysregulated lipid metabolism has emerged as an important factor contributing to TMZ resistance in GBM. The dysregulation of lipid metabolism is a hallmark of cancer and alterations in lipid metabolism have been linked to multiple aspects of tumor biology, including proliferation, migration, and resistance to therapy. In this review, we aimed to summarize current knowledge on lipid metabolism in TMZ-resistant GBM, including key metabolites and proteins involved in lipid synthesis, uptake, and utilization, and recent advances in the application of metabolomics to study lipid metabolism in GBM. We also discussed the potential of lipid metabolism as a target for novel therapeutic interventions. Finally, we highlighted the challenges and opportunities associated with developing these interventions for clinical use, and the need for further research to fully understand the role of lipid metabolism in TMZ resistance in GBM. Our review suggests that targeting dysregulated lipid metabolism may be a promising approach to overcome TMZ resistance and improve outcomes in patients with GBM.

Selective Formation of Acetic Acid and Methanol by Direct Methane Oxidation Using Rhodium Single-Atom Catalysts.

Atomically dispersed catalysts such as single-atom catalysts have been shown to be effective in selectively oxidizing methane, promising a direct synthetic route to value-added oxygenates such as acetic acid or methanol. However, an important challenge of this approach has been that the loading of active sites by single-atom catalysts is low, leading to a low overall yield of the products. Here, we report an approach that can address this issue. It utilizes a metal-organic framework built with porphyrin as the linker, which provides high concentrations of binding sites to support atomically dispersed rhodium. It is shown that up to 5 wt% rhodium loading can be achieved with excellent dispersity. When used for acetic acid synthesis by methane oxidation, a new benchmark performance of 23.62 mmol·gcat-1·h-1 was measured. Furthermore, the catalyst exhibits a unique sensitivity to light, producing acetic acid (under illumination, up to 66.4% selectivity) or methanol (in the dark, up to 65.0% selectivity) under otherwise identical reaction conditions.

Methane Carboxylation Using Electrochemically Activated Carbon Dioxide.

Direct synthesis of CH3 COOH from CH4 and CO2 is an appealing approach for the utilization of two potent greenhouse gases that are notoriously difficult to activate. In this Communication, we report an integrated route to enable this reaction. Recognizing the thermodynamic stability of CO2 , our strategy sought to first activate CO2 to produce CO (through electrochemical CO2 reduction) and O2 (through water oxidation), followed by oxidative CH4 carbonylation catalyzed by Rh single atom catalysts supported on zeolite. The net result was CH4 carboxylation with 100 % atom economy. CH3 COOH was obtained at a high selectivity (>80 %) and good yield (ca. 3.2 mmol g-1 cat in 3 h). Isotope labelling experiments confirmed that CH3 COOH is produced through the coupling of CH4 and CO2 . This work represents the first successful integration of CO/O2 production with oxidative carbonylation reaction. The result is expected to inspire more carboxylation reactions utilizing preactivated CO2 that take advantage of both products from the reduction and oxidation processes, thus achieving high atom efficiency in the synthesis.

SPRTN patient variants cause global-genome DNA-protein crosslink repair defects.

DNA-protein crosslinks (DPCs) are pervasive DNA lesions that are induced by reactive metabolites and various chemotherapeutic agents. Here, we develop a technique for the Purification of x-linked Proteins (PxP), which allows identification and tracking of diverse DPCs in mammalian cells. Using PxP, we investigate DPC repair in cells genetically-engineered to express variants of the SPRTN protease that cause premature ageing and early-onset liver cancer in Ruijs-Aalfs syndrome patients. We find an unexpected role for SPRTN in global-genome DPC repair, that does not rely on replication-coupled detection of the lesion. Mechanistically, we demonstrate that replication-independent DPC cleavage by SPRTN requires SUMO-targeted ubiquitylation of the protein adduct and occurs in addition to proteasomal DPC degradation. Defective ubiquitin binding of SPRTN patient variants compromises global-genome DPC repair and causes synthetic lethality in combination with a reduction in proteasomal DPC repair capacity.

Selective Methane Oxidation by Heterogenized Iridium Catalysts.

Oxidative methane (CH4) carbonylation promises a direct route to the synthesis of value-added oxygenates such as acetic acid (CH3COOH). Here, we report a strategy to realize oxidative CH4 carbonylation through immobilized Ir complexes on an oxide support. Our immobilization approach not only enables direct CH4 activation but also allows for easy separation and reutilization of the catalyst. Furthermore, we show that a key step, methyl migration, that forms a C-C bond, is sensitive to the electrophilicity of carbonyl, which can be tuned by a gentle reduction to the Ir centers. While the as-prepared catalyst that mainly featured Ir(IV) preferred CH3COOH production, a reduced catalyst featuring predominantly Ir(III) led to a significant increase of CH3OH production at the expense of the reduced yield of CH3COOH.