Comprehensive understanding of glioblastoma molecular phenotypes: classification, characteristics, and transition

Among central nervous system-associated malignancies, glioblastoma (GBM) is the most common and has the highest mortality rate. The high heterogeneity of GBM cell types and the complex tumor microenvironment frequently lead to tumor recurrence and sudden relapse in patients treated with temozolomide. In precision medicine, research on GBM treatment is increasingly focusing on molecular subtyping to precisely characterize the cellular and molecular heterogeneity, as well as the refractory nature of GBM toward therapy. Deep understanding of the different molecular expression patterns of GBM subtypes is critical. Researchers have recently proposed tetra fractional or tripartite methods for detecting GBM molecular subtypes. The various molecular subtypes of GBM show significant differences in gene expression patterns and biological behaviors. These subtypes also exhibit high plasticity in their regulatory pathways, oncogene expression, tumor microenvironment alterations, and differential responses to standard therapy. Herein, we summarize the current molecular typing scheme of GBM and the major molecular/genetic characteristics of each subtype. Furthermore, we review the mesenchymal transition mechanisms of GBM under various regulators.

Deep-targeted gene sequencing reveals ARID1A mutation as an important driver of glioblastoma

AIMS

To investigate the key factors influencing glioma progression and the emergence of treatment resistance by examining the intrinsic connection between mutations in DNA damage and repair-related genes and the development of chemoresistance in gliomas.

METHODS

We conducted a comprehensive analysis of deep-targeted gene sequencing data from 228 glioma samples. This involved identifying differentially mutated genes across various glioma grades, assessing their functions, and employing I-TASSER for homology modeling. We elucidated the functional changes induced by high-frequency site mutations in these genes and investigated their impact on glioma progression.

RESULTS

The analysis of sequencing mutation results of deep targeted genes in integration revealed that ARID1A gene mutation occurs frequently in glioblastoma and alteration of ARID1A could affect the tolerance of glioma cells to temozolomide treatment. The deletion of proline at position 16 in the ARID1A protein affected the stability of binding of the SWI/SNF core subunit BRG1, which in turn affected the stability of the SWI/SNF complex and led to altered histone modifications in the CDKN1A promoter region, thereby affecting the biological activity of glioma cells, as inferred from modeling and protein interaction analysis.

CONCLUSION

The ARID1A gene is a critical predictive biomarker for glioma. Mutations at the ARID1A locus alter the stability of the SWI/SNF complex, leading to changes in transcriptional regulation in glioma cells. This contributes to an increased malignant phenotype of GBM and plays a pivotal role in mediating chemoresistance.

Association between infarct location and haemorrhagic transformation of acute ischaemic stroke after intravenous thrombolysis

AIM

To evaluate the association between computed tomography (CT)-based imaging variables at the time of admission and haemorrhagic transformation (HT) after intravenous thrombolysis (IVT).

MATERIALS AND METHODS

One hundred and eight patients who were treated with IVT for acute ischaemic stroke (AIS) during January 2021 to July 2023 were analysed retrospectively. The infarct location was classified as cortical or subcortical in accordance with the Alberta Stroke Program Early CT Score (ASPECTS) system. Logistic regression and receiver operating characteristic curve analyses were performed to determine the relationship between ischaemic variables and HT.

RESULTS

Of the total, 18 (16.7%) patients had HT and seven (6.5%) had symptomatic intracerebral haemorrhage (sICH). Multivariate analysis revealed that cortical ASPECTS was independently associated with HT (odds ratio [OR], 0.197; 95% confidence interval [CI], 0.076-0.511; p=0.001) and cortical ASPECTS was independently associated with sICH (OR, 0.066; 95% CI, 0.009-0.510; p=0.009). To predict HT and sICH, cortical ASPECTS (HT area under the curve [AUC] = 0.881, sICH AUC = 0.971) provided a higher AUC compared with ASPECTS (HT AUC = 0.850, sICH AUC = 0.918).

CONCLUSION

Cortical ASPECTS seen on CT at the time of admission is associated with HT and sICH after IVT.

An optimal de Quervain's tenosynovitis splint with ergonomic thumb support and evenly distributed pressure

Splinting is a conventional treatment for de Quervain's tenosynovitis (dQt). However, existing splints have problems such as excessive thermal discomfort and poor fit, which have been pointed out in previous studies. This study proposes a new functional splint consisting of both hard and soft materials with the aim of providing wear comfort with a good fit and sufficient stability of the injured hand. Thumb support of the splint is an important component that controls and protects the affected thumb. To develop an ergonomically shaped thumb support, 16 participants with dQt were recruited for three-dimensional (3D) scanning of their hands. The angles of the wrist and the curvature of the thumb were measured using computer software, and the results were used as a reference for the design of the prototype supports. Excessive pressure on particular regions, such as bony areas, may cause discomfort or pain. To ensure the wear comfort of the proposed splint, a finite element model (FEM) was built to simulate the wear process of the splint and hence to predict the pressure distribution exerted from the splint onto the hand of the wearer. The simulated results show that the pressure is evenly distributed over the hand, indicating that patients are likely to wear the proposed splint comfortably during their treatment period.

[Effectiveness of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022]

OBJECTIVE

To evaluate the effectiveness of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, so as to provide insights into echinococcosis control.

METHODS

Administrative villages were sampled using a multi-stage cluster random sampling method from Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, and all residents at ages of 12 years and older in the sampled villages were screened for echinococcosis, and schools were sampled using a cluster sampling method, and all children at ages of 12 years and older in the sampled schools were screened for echinococcosis. Domestic dogs were sampled using a systematic random sampling method, and one domestic dog stool sample was collected from each household. Stray dog stool samples were collected outside the villages, and Echinococcus coproantigens were detected using enzyme-linked immunosorbent assay in domestic and stray dogs. In addition, echinococcosis was screened in sheep and cattle in designated slaughterhouses in Tianzhu Tibetan Autonomous County. The trends in the prevalence of echinococcosis in humans and livestock and the positive rate of Echinococcus coproantigens in dogs were examined with the Cochran-Armitage trend test. In addition, individuals screened for echinococcosis were randomly sampled from 2007 to 2022 for survey on the awareness of echinococcosis control knowledge.

RESULTS

A total of 290 356 person-times were screened for echinococcosis among residents at ages of 12 years and older in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 1 094 residents detected with cystic echinococcosis, and the detection of echinococcosis appeared a tendency towards a gradual decline over years (χ2 = 358.602, P < 0.001). A total of 32 931 person-times were screened for echinococcosis among children at ages of 12 years and older in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 296 children detected with echinococcosis, and the detection of echinococcosis appeared a tendency towards a gradual decline over years (χ2 = 267.673, P < 0.001). A total of 33 230 domestic dog stool samples were tested for Echinococcus coproantigens in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 1 777 Echinococcus coproantigens-positive samples tested, and the positive rate of Echinococcus coproantigens appeared a tendency towards a decline in domestic dogs over years (χ2 = 2 210.428, P < 0.001), while the positive rate of Echinococcus coproantigens showed a tendency towards a rise in domestic animals from 2016 to 2022 (χ2 = 37.745, P < 0.001). The positive rate of Echinococcus coproantigens remained relatively stable in stray dogs in Tianzhu Tibetan Autonomous County, Gansu Province from 2019 to 2022 (χ2 = 0.315, P = 0.575). A total of 10 973 sheep were screened for echinococcosis in Tianzhu Tibetan Autonomous County from 2007 to 2022, with 334 sheep detected with echinococcosis, and the detection of echinococcosis appeared a tendency towards a decline in sheep over years (χ2 = 53.579, P < 0.001); however, there was no significant change in the detection of echinococcosis during the period from 2015 through 2022 (χ2 = 1.520, P = 0.218). A total of 2 400 cattle were screened for echinococcosis in Tianzhu Tibetan Autonomous County from 2017 to 2022, with 231 cattle detected with echinococcosis, and the detection of echinococcosis showed a tendency towards a decline over years (χ2 = 5.579, P < 0.05). The awareness of echinococcosis control knowledge increased from 44.37% in 2007 to 94.00% in 2022 among residents at ages of 12 years and older and from 52.50% in 2007 to 92.50% in 2022 among children at ages of 12 years and older in Tianzhu Tibetan Autonomous County, respectively.

CONCLUSIONS

There has been a reduction in the detection of echinococcosis in humans and domestic animals and the positive rate of Echinococcus coproantigens in dogs and a rise in the awareness of the echinococcosis control knowledge following the implementation of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province; however, integrated echinococcosis control measures are still required for further control of the prevalence of echinococcosis.

Plasma levels of CD36 and glutathione as biomarkers for ruptured intracranial aneurysm

Evidence has proved that intracranial aneurysm (IA) formation and rupture might be closely related to inflammatory response and oxidative stress. Our objective was to evaluate the potential of CD36 and glutathione (GSH) as biomarkers for IA. In this study, the enzyme-linked immunosorbent assay was used to measure the plasma levels of CD36 and GSH in 30 IA patients and 30 healthy controls. Then, correlation analysis, receiver operating characteristic (ROC) curve, and logistic regression analysis were performed. The results showed that the plasma level of CD36 in IA patients was significantly higher than that in the control group (P < 0.0001), and plasma GSH was significantly lower compared with that in the control group (P < 0.0001). ROC analysis showed that CD36 and GSH had high sensitivity (90.0 and 96.6%) and specificity (96.6 and 86.6%) for IA diagnosis. The combined sensitivity and specificity achieved were 100 and 100%, respectively. The plasma levels of CD36 and GSH did not show a significant correlation with age, the Glasgow Coma Scale, Hunter-Hess score, aneurysm size, aneurysm height, aneurysm neck, and aspect ratio. The AUC of the logistic regression model based on CD36 and GSH was 0.505. Our results suggested that the combination of plasma CD36 and GSH could serve as potential biomarkers for IA rupture.

Identification of miRNAs Involved in Intracranial Aneurysm Rupture in Cigarette-Smoking Patients

INTRODUCTION

Smoking is an independent risk factor for the formation and rupture of intracranial aneurysms (IA). However, the underlying mechanism remains unclear.

METHODS

In this study, we performed miRNA sequencing on plasma from 10 smoking patients with IA, 10 non-smoking patients with IA, and 10 healthy controls. The differentially expressed miRNAs (DE miRNAs) between smoking and non-smoking patients with IA were identified. Functional and pathway enrichment analysis is employed to investigate the potential functions of those DE miRNA target genes. The correlations with the clinical parameters were assessed using receiver operating characteristic curve (ROC) analysis.

RESULTS

In total, we identified 428 DE miRNAs. Functional enrichment analysis showed the target genes were significantly enriched in biological aspects related to cell characteristics, such as cell cycle, cell differentiation, and cell migration. Pathway analysis showed DE miRNAs mainly enriched in the PI3K-Akt signaling pathway, Focal adhesion, and JAK-STAT signaling pathway. The expressions of miR-574-5p, miR-151a-3p, and miR-652-3p correlated well with aneurysm parameters. The AUC of miR-574-5p, miR-151a-3p, and miR-652-3p were 97%, 92%, and 99%, respectively.

CONCLUSION

Our study indicated that smoking significantly altered the plasma miRNA profile in patients with IA. The expression of miR-574-5p, miR-151a-3p, and miR-652-3p correlated with aneurysm parameters, which may play a significant role in the formation and rupture of IA.

Blockage of EGFR/AKT and mevalonate pathways synergize the antitumor effect of temozolomide by reprogramming energy metabolism in glioblastoma

BACKGROUND

Metabolism reprogramming plays a vital role in glioblastoma (GBM) progression and recurrence by producing enough energy for highly proliferating tumor cells. In addition, metabolic reprogramming is crucial for tumor growth and immune-escape mechanisms. Epidermal growth factor receptor (EGFR) amplification and EGFR-vIII mutation are often detected in GBM cells, contributing to the malignant behavior. This study aimed to investigate the functional role of the EGFR pathway on fatty acid metabolism remodeling and energy generation.

METHODS

Clinical GBM specimens were selected for single-cell RNA sequencing and untargeted metabolomics analysis. A metabolism-associated RTK-fatty acid-gene signature was constructed and verified. MK-2206 and MK-803 were utilized to block the RTK pathway and mevalonate pathway induced abnormal metabolism. Energy metabolism in GBM with activated EGFR pathway was monitored. The antitumor effect of Osimertinib and Atorvastatin assisted by temozolomide (TMZ) was analyzed by an intracranial tumor model in vivo.

RESULTS

GBM with high EGFR expression had characteristics of lipid remodeling and maintaining high cholesterol levels, supported by the single-cell RNA sequencing and metabolomics of clinical GBM samples. Inhibition of the EGFR/AKT and mevalonate pathways could remodel energy metabolism by repressing the tricarboxylic acid cycle and modulating ATP production. Mechanistically, the EGFR/AKT pathway upregulated the expressions of acyl-CoA synthetase short-chain family member 3 (ACSS3), acyl-CoA synthetase long-chain family member 3 (ACSL3), and long-chain fatty acid elongation-related gene ELOVL fatty acid elongase 2 (ELOVL2) in an NF-κB-dependent manner. Moreover, inhibition of the mevalonate pathway reduced the EGFR level on the cell membranes, thereby affecting the signal transduction of the EGFR/AKT pathway. Therefore, targeting the EGFR/AKT and mevalonate pathways enhanced the antitumor effect of TMZ in GBM cells and animal models.

CONCLUSIONS

Our findings not only uncovered the mechanism of metabolic reprogramming in EGFR-activated GBM but also provided a combinatorial therapeutic strategy for clinical GBM management.

EPIC-0307-mediated selective disruption of PRADX-EZH2 interaction and enhancement of temozolomide sensitivity to glioblastoma via inhibiting DNA repair and MGMT

BACKGROUND

Temozolomide (TMZ) treatment efficacy in glioblastoma (GBM) has been limited by resistance. The level of O-6-methylguanine-DNA methyltransferase (MGMT) and intrinsic DNA damage repair factors are important for the TMZ response in patients. Here, we reported a novel compound, called EPIC-0307, that increased TMZ sensitivity by inhibiting specific DNA damage repair proteins and MGMT expression.

METHODS

EPIC-0307 was derived by molecular docking screening. RNA immunoprecipitation (RIP), and chromatin immunoprecipitation by RNA (ChIRP) assays were used to verify the blocking effect. Chromatin immunoprecipitation (ChIP) and co-immunoprecipitation (Co-IP) assays were performed to explore the mechanism of EPIC-0307. A series of in vivo and in vitro experiments were designed to evaluate the efficacy of EPIC-0307 in sensitizing GBM cells to TMZ.

RESULTS

EPIC-0307 selectively disrupted the binding of PRADX to EZH2 and upregulated the expression of P21 and PUMA, leading to cell cycle arrest and apoptosis in GBM cells. EPIC-0307 exhibited a synergistic inhibitory effect on GBM when combined with TMZ by downregulating TMZ-induced DNA damage repair responses and epigenetically silencing MGMT expression through modulating the recruitment of ATF3-pSTAT3-HDAC1 regulatory complex to the MGMT promoter. EPIC-0307 demonstrated significant efficacy in suppressing the tumorigenesis of GBM cells, restoring TMZ sensitivity.

CONCLUSION

This study identified a potential small-molecule inhibitor (SMI) EPIC-0307 that selectively disrupted the PRADX-EZH2 interaction to upregulate expressions of tumor suppressor genes, thereby exerting its antitumor effects on GBM cells. EPIC-0307 treatment also increased the chemotherapeutic efficacy of TMZ by epigenetically downregulating DNA repair-associate genes and MGMT expression in GBM cells.

Genome-wide association study for charcoal rot resistance in soybean harvested in Kazakhstan

Charcoal rot (CR) caused by the fungal pathogen Macrophomina phaseolina is a devastating disease affecting soybean (Glycine max (L.) Merrill.) worldwide. Identifying the genetic factors associated with resistance to charcoal rot is crucial for developing disease-resistant soybean cultivars. In this research, we conducted a genome-wide association study (GWAS) using different models and genotypic data to unravel the genetic determinants underlying soybean resistance to сharcoal rot. The study relied on a panel of 252 soybean accessions, comprising commercial cultivars and breeding lines, to capture genetic variations associated with resistance. The phenotypic evaluation was performed under natural conditions during the 2021-2022 period. Disease severity and survival rates were recorded to quantify the resistance levels in the accessions. Genotypic data consisted of two sets: the results of genotyping using the Illumina iSelect 6K SNP (single-nucleotide polymorphism) array and the results of whole-genome resequencing. The GWAS was conducted using four different models (MLM, MLMM, FarmCPU, and BLINK) based on the GAPIT platform. As a result, SNP markers of 11 quantitative trait loci associated with CR resistance were identified. Candidate genes within the identified genomic regions were explored for their functional annotations and potential roles in plant defense responses. The findings from this study may further contribute to the development of molecular breeding strategies for enhancing CR resistance in soybean cultivars. Marker-assisted selection can be efficiently employed to accelerate the breeding process, enabling the development of cultivars with improved resistance to сharcoal rot. Ultimately, deploying resistant cultivars may significantly reduce yield losses and enhance the sustainability of soybean production, benefiting farmers and ensuring a stable supply of this valuable crop.

Radionecrosis mimicking pseudo‑progression in a patient with lung cancer and brain metastasis following the combination of anti‑PD‑1 therapy and stereotactic radiosurgery: A case report

Brain metastases (BMs) usually develop in patients with non-small cell lung cancer. In addition to systemic therapy, radiation therapy and surgery, anti-programmed cell death-ligand 1 (PD-L1) therapy is another promising clinical anticancer treatment modality. However, the optimal timing and drug-drug interactions of anti-PD-L1 therapy with other combined treatments remain to be elucidated. Treatment with anti-PD-L1 therapy is associated with an increased risk of radionecrosis (RN) regardless of tumor histology. The present study described a case of RN in a patient with lung adenocarcinoma and with BM who received anti-PD-L1 therapy. Before anti-PD-L1 treatment, the patient received whole brain radiotherapy. During durvalumab treatment, the intracranial metastases regressed. The progression of intracranial lesions 9 months later prompted a second-line of therapy with PD-L1 inhibitor durvalumab and stereotactic radiotherapy (SRT). Despite stereotactic irradiation, the lesions progressed further, leading to surgical resection. On examination, RN was detected, but there was no evidence of metastatic lung cancer. The aim of the present study was to present the longitudinal change in magnetic resonance imaging in RN following STR and anti-PD-L1 combined therapy. The atypical image of RN is conditionally important for making an accurate preoperative diagnosis.

Development of glioblastoma organoids and their applications in personalized therapy

Glioblastomas (GBMs) are the brain tumors with the highest malignancy and poorest prognoses. GBM is characterized by high heterogeneity and resistance to drug treatment. Organoids are 3-dimensional cultures that are constructed in vitro and comprise cell types highly similar to those in organs or tissues in vivo, thus simulating specific structures and physiological functions of organs. Organoids have been technically developed into an advanced ex vivo disease model used in basic and preclinical research on tumors. Brain organoids, which simulate the brain microenvironment while preserving tumor heterogeneity, have been used to predict patients' therapeutic responses to antitumor drugs, thus enabling a breakthrough in glioma research. GBM organoids provide an effective supplementary model that reflects human tumors' biological characteristics and functions in vitro more directly and accurately than traditional experimental models. Therefore, GBM organoids are widely applicable in disease mechanism research, drug development and screening, and glioma precision treatments. This review focuses on the development of various GBM organoid models and their applications in identifying new individualized therapies against drug-resistant GBM.

Identification of key genes of anti-programmed death ligand 1 for meningioma immunotherapy by bioinformatic analysis

Meningioma is one of the most common primary tumors in the central nervous system (CNS). A deeper understanding of its molecular characterization could provide potential therapeutic targets to reduce recurrence. In this study, we attempted to identify specific gene mutations in meningioma for immunotherapy. One GSE43290 dataset was obtained from the Gene Expression Omnibus (GEO) database to find differentially expressed genes (DEGs) between meningioma tissues and normal meninges. In total, 420 DEGs were identified, including 15 up-regulated and 405 down-regulated genes. Functional enrichment analysis showed that these DEGs were mainly enriched in PI3K-Akt signaling pathway, Focal adhesion, and MAPK signaling pathway. We identified 20 hub genes by protein-protein interaction (PPI) analysis. Among the hub genes, the expression of FLT1, CXCL8, JUN, THBS1, FECAM1, CD34, and FGF13 were negatively correlated with Programmed Death Ligand-1 (PD-L1). Additionally, the expression of those genes was co-regulated by miR-155-5p. The findings suggest that miR-155-5p play an important role in the pathogenesis of meningioma and may represent potential therapeutic targets for its anti-PD-L1 immunotherapy.

The diagnostic significance of cerebrospinal fluid cytology and circulating tumor DNA in meningeal carcinomatosis

Objective

The objective of this research is to investigate the clinical application value of cerebrospinal fluid (CSF) cytology and circulating tumor DNA (ctDNA) in lung adenocarcinoma (LUAD) meningeal metastasis-meningeal carcinomatosis (MC), and to further explore the possible molecular mechanisms and drug treatment targets of LUAD meningeal metastasis by next-generation sequencing (NGS).

Methods

We retrospectively analyzed LUAD with MC in 52 patients. CSF cytology was carried out using the slide centrifugation precipitation method and May-Grüwald-Giemsa (MGG) staining. Tumor tissue, plasma and CSF ctDNA of some MC patients were detected by NGS.

Results

Of the 52 MC patients, 46 (88.46%) were positive for CSF cytology and 34 (65.38%) were positive for imaging, with statistically significant differences in diagnostic positivity (P < 0.05). In 32 of these patients, CSF cytology, cerebrospinal fluid ctDNA, plasma ctDNA and MRI examination were performed simultaneously, and the positive rates were 84.38, 100, 56.25, and 62.50% respectively, the difference was statistically significant (P < 0.001). Analysis of the NGS profiles of tumor tissues, plasma and CSF of 12 MC patients: the mutated gene with the highest detection rate was epidermal growth factor receptor (EGFR) and the detection rate were 100, 58.33, and 100% respectively in tumor tissues, plasma and CSF, and there were 6 cases of concordance between plasma and tissue EGFR mutation sites, with a concordance rate of 50.00%, and 12 cases of concordance between CSF and tissue EGFR mutation sites, with a concordance rate of 100%. In addition, mutations not found in tissue or plasma were detected in CSF: FH mutation, SETD2 mutation, WT1 mutation, CDKN2A mutation, CDKN2B mutation, and multiple copy number variants (CNV), with the most detected being CDKN2A mutation and MET amplification.

Conclusion

CSF cytology is more sensitive than traditional imaging in the diagnosis of meningeal carcinomatosis and has significant advantages in the early screening and diagnosis of MC patients. CSF ctDNA can be used as a complementary diagnostic method to negative results of CSF cytology and MRI, and CSF ctDNA can be used as an important method for liquid biopsy of patients with MC, which has important clinical significance in revealing the possible molecular mechanisms and drug treatment targets of meningeal metastasis of LUAD.

Comparison of the diagnostic value of liquid biopsy in leptomeningeal metastases: A systematic review and meta-analysis

Background

Brain metastases (BM) include brain parenchymal (BPM) and leptomeningeal metastases (LM), which are associated with a poor prognosis and high mortality rate. Early and accurate diagnosis and timely, effective treatment are crucial for improving the overall survival of LM patients. Cerebrospinal fluid (CSF) biopsy technology has attracted widespread attention for its diagnostic value in diverse cancers, including LM. We summarized studies to compare the potential diagnostic value of CSF liquid biopsy techniques in BM patients with meta-analysis.

Methods

The study protocol was prospectively registered in PROSPERO, registration number CRD42022373263. We obtained the literature on liquid biopsy for BM from 7 databases (PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, and Wanfang Data knowledge service platform). Then, a systematic review of those studies was performed according to PRISMA criteria.

Results

Nine publications have been obtained, and we found CSF liquid biopsy techniques to be more suitable for diagnosing LM. We analyzed the sensitivity, specificity, and area under the curve (AUC) of CSF liquid biopsy. The overall sensitivity, specificity, and AUC of CSF liquid biopsy in the diagnosis of LM were 0.65 (95% CI: 0.48 - 0.79), 0.70 (95% CI: 0.50 - 0.86), and 0.69, respectively. Then, we compared the diagnostic advantages of CSF liquid biopsy techniques and CSF cytology in LM. The results show that CSF liquid biopsy is superior to CSF cytology in LM diagnosis.

Conclusions

Our meta-analysis suggested that CSF liquid biopsy is more suitable for LM diagnosis and has higher accuracy than CSF cytology.

Blood exosomes-based targeted delivery of cPLA2 siRNA and metformin to modulate glioblastoma energy metabolism for tailoring personalized therapy

BACKGROUND

Targeting glioblastoma (GBM) energy metabolism through multiple metabolic pathways has emerged as an effective therapeutic approach. Dual inhibition of phospholipid and mitochondrial metabolism with cytoplasmic phospholipase A2 (cPLA2) knockdown and metformin treatment could be a potential strategy. However, the strategic prerequisite is to explore a carrier capable of co-delivering the therapeutic combination to cross the blood-brain barrier (BBB) and preferentially accumulate at the GBM site.

METHODS

Blood exosomes (Exos) were selected as the combination delivery carriers. The cellular uptake of Exos and the therapeutic effects of the combination strategy were evaluated in primary GBM cells. In vivo GBM-targeted delivery efficiency and anti-GBM efficacy were tested in a patient-derived xenograft (PDX) model.

RESULTS

Here, we showed that the Exos-mediated cPLA2 siRNA/metformin combined strategy could regulate GBM energy metabolism for personalized treatment. Genomic analysis and experiments showed that polymerase 1 and transcript release factor (PTRF, a biomarker of GBM) positively regulated the uptake of Exos by GBM cells, confirming the feasibility of the delivery strategy. Further, Exos could co-load cPLA2 siRNA (sicPLA2) and metformin and co-deliver them across the BBB and into GBM tissue. The mitochondrial energy metabolism of GBM was impaired with this combination treatment (Exos-Met/sicPLA2). In the PDX GBM model, systemic administration of Exos-Met/sicPLA2 reduced tumor growth and prolonged survival.

CONCLUSIONS

Our findings demonstrated that Exos-based combined delivery of sicPLA2 and metformin selectively targeted the GBM energy metabolism to achieve antitumor effects, showing its potential as a personalized therapy for GBM patients.

A Case Series of Bosworth Fracture-Dislocations and Review of 129 Reported Cases

Introduction

Bosworth fracture dislocations of the ankle are rare injuries of the ankle caused by extreme external rotation of the supinated foot where the proximal fibula fracture fragment is posteriorly dislocated and entrapped behind the posterior-lateral ridge of the tibia. This case series aims to document three such cases treated in our institution over a nine year period. We also provide a review of 129 cases in the existing literature.

Materials and methods

Medical records and relevant radiographs for each patient were analysed and collected from the time of presentation till the point of latest follow-up. During each clinic visit, all physical exam findings as well as all complications were recorded. The American Foot and Ankle Society (AOFAS) Hindfoot score was also tabulated for each patient at the point of latest review.

Results

Closed reduction was unsuccessful in all three patients, and all required open reduction. One patient had an uncomplicated recovery whilst the remaining two suffered significant soft tissue complications. One patient suffered severe soft tissue swelling preventing primary closure at the time of surgery, whilst another suffered post-operative wound dehiscence and infection. Eventually all fractures healed, and all three patients obtained satisfactory AOFAS scores.

Conclusion

The diagnosis of Bosworth fracture dislocations of the ankle is often delayed or missed, due to its rare occurrence. Closed reduction is often unsuccessful, and early open reduction is required to avoid poor clinical outcomes due to severe soft tissue damage or even compartment syndrome.

Origin, activation, and targeted therapy of glioma-associated macrophages

The glioma tumor microenvironment plays a crucial role in the development, occurrence, and treatment of gliomas. Glioma-associated macrophages (GAMs) are the most widely infiltrated immune cells in the tumor microenvironment (TME) and one of the major cell populations that exert immune functions. GAMs typically originate from two cell types-brain-resident microglia (BRM) and bone marrow-derived monocytes (BMDM), depending on a variety of cytokines for recruitment and activation. GAMs mainly contain two functionally and morphologically distinct activation types- classically activated M1 macrophages (antitumor/immunostimulatory) and alternatively activated M2 macrophages (protumor/immunosuppressive). GAMs have been shown to affect multiple biological functions of gliomas, including promoting tumor growth and invasion, angiogenesis, energy metabolism, and treatment resistance. Both M1 and M2 macrophages are highly plastic and can polarize or interconvert under various malignant conditions. As the relationship between GAMs and gliomas has become more apparent, GAMs have long been one of the promising targets for glioma therapy, and many studies have demonstrated the therapeutic potential of this target. Here, we review the origin and activation of GAMs in gliomas, how they regulate tumor development and response to therapies, and current glioma therapeutic strategies targeting GAMs.

TCA-phospholipid-glycolysis targeted triple therapy effectively suppresses ATP production and tumor growth in glioblastoma

Rationale: Glioblastoma (GBM) displays a complex metabolic reprogramming in cancer cells. Adenosine triphosphate (ATP) is one of the central mediators of cell metabolism and signaling. GBM cells generate ATP by glycolysis and the tricarboxylic acid (TCA) cycle associated with oxidative phosphorylation (OXPHOS) through the breaking-down of pyruvate or fatty acids to meet the growing energy demand of cancer cells. Therefore, it's urgent to develop novel treatments targeting energy metabolism to hinder tumor cell proliferation in GBM.

Methods: Non-targeted metabolomic profiling analysis was utilized to evaluate cell metabolic reprogramming using a small molecule inhibitor (SMI) EPIC-0412 treatment. Cellular oxygen consumption rate (OCR) and the total proton efflux rate (PER), as well as ATP concentration, were tracked to study metabolic responses to specifically targeted inhibitors, including EPIC-0412, arachidonyl trifluoromethyl ketone (AACOCF3), and 2 deoxy-D-glucose (2-DG). Cancer cell proliferation was assessed by CCK-8 measurements and colony formation assay. Additionally, flow cytometry, immunoblotting (IB), and immunofluorescence (IF) analyses were performed with GBM cells to understand their tumorigenic properties under treatments. Finally, the anticancer effects of this combination therapy were evaluated in the GBM mouse model by convection-enhanced delivery (CED).

Results: We found that SMI EPIC-0412 could effectively perturb the TCA cycle, which participated in the combination therapy of cytosolic phospholipase A2 (cPLA2)-inhibitor AACOCF3, and hexokinase II (HK2)-inhibitor 2-DG to disrupt the GBM energy metabolism for targeted metabolic treatments. ATP production was significantly declined in glioma cells when treated with monotherapy (EPIC-0412 or AACOCF3), dual therapy (EPIC-0412 + AACOCF3), or triple therapy (EPIC-0412 + AACOCF3 +2-DG) regimen. Our experiments revealed that these therapies hindered glioma cell proliferation and growth, leading to the reduction in ATP production and G0/G1 cell cycle arrest. We demonstrated that the combination therapy effectively extended the survival of cerebral tumor-bearing mice.

Conclusion: Our findings indicate that the TCA-phospholipid-glycolysis metabolism axis can be blocked by specific inhibitors that significantly disrupt the tumor energy metabolism and suppress tumor proliferation in vitro and in vivo, suggesting that targeting ATP synthesis inhibition in cancer cells might be an attractive therapeutic avenue in GBM management.

A clinical investigation into the usefulness of fractional exhaled nitric oxide in guiding glucocorticoid therapy in children with bronchial asthma

The present study aims to investigate the value of fractional exhaled nitric oxide (FeNO) combined with pulmonary function in guiding the dose adjustment of inhaled glucocorticosteroids (ICSs) in children with asthma. A total of 133 children aged 6-12 years with newly diagnosed asthma were enrolled as the study subjects and randomly divided into the experimental group (n=68) and the control group (n=65). After three months of ICS treatment, in the experimental group, the dose of ICSs was adjusted based on the control status of the children and the results of the pulmonary function tests and FeNO assays, and in the control group, the dose was adjusted based on the control status of the children and the results of the pulmonary function tests. After another three months of treatment, the number of acute asthma attacks and the Childhood Asthma Control Test (C-ACT) scores were compared between the two groups, and the outcome of pulmonary function tests and FeNO assays during treatment were analyzed. When examining pulmonary function and FeNO levels, when compared with before treatment, there were no statistically significant differences in either group or between the groups after three months of ICS treatment (P>0.05). After dose adjustment and another three months of treatment, when compared with the control group, the improvement in pulmonary function in the experimental group was greater, the reduction in FeNO levels was greater, the incidence of acute asthma attacks was lower, and the C-ACT score was higher (P<0.05). We concluded that the combination of FeNO assays and pulmonary function tests to guide the ICS dose adjustment in children with asthma could improve asthma control and reduce the risk of acute asthma attacks.

lncRNA PRADX is a Mesenchymal Glioblastoma Biomarker for Cellular Metabolism Targeted Therapy

Glioblastoma (GBM) is the most common and lethal type of primary malignant central nervous system (CNS) tumor with an extremely poor prognosis, and the mesenchymal subtype of GBM has the worst prognosis. Here, we found that lncRNA PRADX was overexpressed in the mesenchymal GBM and was transcriptionally regulated by RUNX1-CBFβ complex, overexpressed PRADX suppressed BLCAP expression via interacting with EZH2 and catalyzing trimethylation of lysine 27 on histone H3 (H3K27me3). Moreover, we showed that BLCAP interacted with STAT3 and reduced STAT3 phosphorylation, overexpressed PRADX activated STAT3 phosphorylation, and promoted ACSL1 expression via suppressing BLCAP expression, accelerating tumor metabolism. Finally, we determined that combined of ACSL1 and CPT1 inhibitors could reverse the accelerated cellular metabolism and tumor growth induced by PRADX overexpression in vivo and in vitro. Collectively, PRADX/PRC2 complex activated the STAT3 pathway and energy metabolism in relation to mesenchymal GBM progression. Furthermore, our findings provided a novel therapeutic strategy targeting the energy metabolism activity of GBM.

[Metagenomic data-analysis reveals enrichment of lipopolysaccharide synthesis in the gut microbiota of atrial fibrillation patients]

Objective: To investigate the functional changes of key gut microbiota (GM) that produce lipopolysaccharide (LPS) in atrial fibrillation (AF) patients and to explore their potential role in the pathogenesis of AF. Methods: This was a prospective cross-sectional study. Patients with AF admitted to Beijing Chaoyang Hospital of Capital Medical University were enrolled from March 2016 to December 2018. Subjects with matched genetic backgrounds undergoing physical examination during the same period were selected as controls. Clinical baseline data and fecal samples were collected. Bacterial DNA was extracted and metagenomic sequencing was performed by using Illumina Novaseq. Based on metagenomic data, the relative abundances of KEGG Orthology (KO), enzymatic genes and species that harbored enzymatic genes were acquired. The key features were selected via the least absolute shrinkage and selection operator (LASSO) analysis. The role of GM-derived LPS biosynthetic feature in the development of AF was assessed by receiver operating characteristic (ROC) curve, partial least squares structural equation modeling (PLS-SEM) and logistic regression analysis. Results: Fifty nonvalvular AF patients (mean age: 66.0 (57.0, 71.3), 32 males(64%)) were enrolled as AF group. Fifty individuals (mean age 55.0 (50.5, 57.5), 41 males(82%)) were recruited as controls. Compared with the controls, AF patients showed a marked difference in the GM genes underlying LPS-biosynthesis, including 20 potential LPS-synthesis KO, 7 LPS-biosynthesis enzymatic genes and 89 species that were assigned as taxa harbored nine LPS-enzymatic genes. LASSO regression analysis showed that 5 KO, 3 enzymatic genes and 9 species could be selected to construct the KO, enzyme and species scoring system. Genes enriched in AF group included 2 KO (K02851 and K00972), 3 enzymatic genes (LpxH, LpxC and LpxK) and 7 species (Intestinibacter bartlettii、Ruminococcus sp. JC304、Coprococcus catus、uncultured Eubacterium sp.、Eubacterium sp. CAG:251、Anaerostipes hadrus、Dorea longicatena). ROC curve analysis revealed the predictive capacity of differential GM-derived LPS signatures to distinguish AF patients in terms of above KO, enzymatic and species scores: area under curve (AUC)=0.957, 95%CI: 0.918-0.995, AUC=0.940, 95%CI 0.889-0.991, AUC=0.972, 95%CI 0.948-0.997. PLS-SEM showed that changes in lipopolysaccharide-producing bacteria could be involved in the pathogenesis of AF. The key KO mediated 35.17% of the total effect of key bacteria on AF. After incorporating the clinical factors of AF, the KO score was positively associated with the significantly increased risk of AF (OR<0.001, 95%CI:<0.001-0.021, P<0.001). Conclusion: Microbes involved in LPS synthesis are enriched in the gut of AF patients, accompanied with up-regulated LPS synthesis function by encoding the LPS-enzymatic biosynthesis gene.

PTRF/Cavin-1 as a Novel RNA-Binding Protein Expedites the NF-κB/PD-L1 Axis by Stabilizing lncRNA NEAT1, Contributing to Tumorigenesis and Immune Evasion in Glioblastoma

Background

Immunotherapy, especially checkpoint inhibitors targeting PD-1 or PD-L1, has revolutionized cancer therapy. However, PD-1/PD-L1 inhibitors have not been investigated thoroughly in glioblastoma (GBM). Studies have shown that polymerase 1 and transcript release factor (PTRF/Cavin-1) has an immune-suppressive function in GBM. Thus, the relationship between PTRF and PD-L1 and their role in immune suppression requires further investigation in GBM.

Methods

We used public databases and bioinformatics analysis to investigate the relationship between PTRF and PD-L1. We next confirmed the predicted relationship between PTRF and PD-L1 in primary GBM cell lines by using different experimental approaches. RIP-Seq, RIP, ChIP, and qRT-PCR were conducted to explore the molecular mechanism of PTRF in immunosuppression.

Results

We found that PTRF stabilizes lncRNA NEAT1 to induce NF-κB and PD-L1 and promotes immune evasion in GBM. PTRF was found to correlate with immunosuppression in the public GBM databases. PTRF increased the level of PD-L1 in primary cell lines from GBM patients. We carried out RIP-Seq of GBM cells and found that PTRF interacts with lncRNA NEAT1 and stabilizes its mRNA. PTRF also promoted the activity of NF-κB by suppressing UBXN1 expression via NEAT1 and enhanced the transcription of PD-L1 through NF-κB activation. Finally, PTRF promoted immune evasion in GBM cells by regulating PD-1 binding and PD-L1 mediated T cell cytotoxicity.

Conclusions

In summary, our study identified the PTRF-NEAT1-PD-L1 axis as a novel immune therapeutic target in GBM.

Buntanetap, a Novel Translational Inhibitor of Multiple Neurotoxic Proteins, Proves to Be Safe and Promising in Both Alzheimer's and Parkinson's Patients

BACKGROUND

Previously we reported the clinical safety and pharmacological activity of buntanetap (known as Posiphen or ANVS401) in healthy volunteers and mild cognitive impaired (MCI) patients (21). The data supported continued clinical evaluation of buntanetap for treating Alzheimer's Disease (AD). Neurodegenerative diseases such as AD and Parkinson's disease (PD) share several pathological manifestations, including increased levels of multiple neurotoxic protein aggregates. Therefore, a treatment strategy that targets toxic species common to both disorders can potentially provide better clinical outcomes than attacking one neurotoxic protein alone. To test this hypothesis, we recently completed a clinical study in early AD and early PD participants and report the data here.

OBJECTIVES

We evaluated safety, pharmacokinetics, biomarkers, and efficacy of buntanetap in treating early AD and PD patients.

DESIGN

Double-blind, placebo-controlled, multi-center study.

SETTING

13 sites in the US participated in this clinical trial. The registration number is NCT04524351 at ClinicalTrials.gov.

PARTICIPANTS

14 early AD patients and 54 early PD patients.

INTERVENTION

AD patients were given either 80mg buntanetap or placebo QD. PD patients were given 5mg, 10mg, 20mg, 40mg, 80mg buntanetap or placebo QD.

MEASUREMENTS

Primary endpoint is safety and tolerability; secondary endpoint is pharmacokinetics of buntanetap in plasma; exploratory endpoints are 1) biomarkers in cerebrospinal fluid (CSF) in both AD and PD patients 2) psychometric tests specific for AD (ADAS-Cogs and WAIS coding test) or PD (MDS-UPDRS and WAIS coding test).

RESULTS

Buntanetap was safe and well tolerated. Biomarker data indicated a trend in lowering levels of neurotoxic proteins and inflammatory factors and improving axonal integrity and synaptic function in both AD and PD cohorts. Psychometric tests showed statistically significant improvements in ADAS-Cog11 and WAIS coding in AD patients and MDS-UPDRS and WAIS coding in PD patients.

CONCLUSIONS

Buntanetap is well tolerated and safe at doses up to 80mg QD in both AD and PD patients. Cmax and AUC increase with dose without evidence for a plateau up to 80mg QD. The drug shows promising evidence in exploratory biomarker and efficacy measures. Further evaluation of buntanetap in larger, longer-term clinical trials for the treatment of AD and PD are warranted.

PTRF/Cavin-1 enhances chemo-resistance and promotes temozolomide efflux through extracellular vesicles in glioblastoma

Background: The concentration and duration of intracellular drugs have always been the key factors for determining the efficacy of the treatment. Efflux of chemotherapeutic drugs or anticancer agents is a major reason for multidrug resistance generation in cancer cells. The high expression of polymerase I and transcript release factor (PTRF) is correlated with a worse prognosis in glioma patients. However, the importance of PTRF on temozolomide (TMZ) resistance in glioblastoma (GBM) is poorly understood.

Methods: TCGA data analysis, CGGA data analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM), clone formation, cell counting kit-8 (cck-8), western blot (WB), immunofluorescence (IF), immunohistochemistry (IHC) and flow cytometry assays were performed to investigate the underlying mechanism and effect of PTRF on TMZ-resistance in a variety of GBM cell lines and GBM patient-derived xenograft (PDX) models. Clone formation, WB, IF, IHC and flow cytometry assays were performed to examine the efficacy of sequential therapy of TMZ followed by CQ in GBM cells and PDX models.

Results: The prognosis of GBM patients treated with TMZ was negatively correlated with PTRF expression. Our results reveal that PTRF knockdown significantly decrease proliferation and increase apoptosis in GBM after TMZ treatment. Moreover, PTRF contribute to TMZ-resistance by increasing TMZ efflux through extracellular vesicles (EVs). Furthermore, our results demonstrate that sequential therapy of TMZ followed by CQ significantly promotes the TMZ efficacy against GBM by increasing intracellular TMZ concentration ([TMZ]i).

Conclusion: This study highlights that PTRF can act as an independent biomarker to predict the prognosis of GBM patients after TMZ treatment and describes a new mechanism contributing to TMZ-resistance. In addition, this study may provide a novel idea for GBM therapy.

ALKBH5 Facilitates Hypoxia-Induced Paraspeckle Assembly and IL8 Secretion to Generate an Immunosuppressive Tumor Microenvironment

The dynamic changes of RNA N6-methyl-adenosine (m⁶A) during cancer progression contribute to quick adaption to microenvironmental changes. Here, we profiled the cancer cell m⁶A dynamics in the hypoxic tumor niche and its pathological consequences in glioblastoma multiforme (GBM). The m⁶A demethylase ALKBH5 was induced in GBM models under hypoxic conditions and was associated with a hypoxic gene signature in GBM patient samples. Depletion or inactivation of ALKBH5 in GBM cells significantly suppressed hypoxia-induced tumor-associated macrophage (TAM) recruitment and immunosuppression in allograft tumors. Expression and secretion of CXCL8/IL8 were significantly suppressed in ALKBH5-deficient tumors. However, ALKBH5 did not regulate CXCL8 m⁶A directly. Instead, hypoxia-induced ALKBH5 erased m⁶A deposition from the lncRNA NEAT1, stabilizing the transcript and facilitating NEAT1-mediated paraspeckle assembly, which led to relocation of the transcriptional repressor SFPQ from the CXCL8 promoter to paraspeckles and, ultimately, upregulation of CXCL8/IL8 expression. Accordingly, ectopic expression of CXCL8 in ALKBH5-deficient GBM cells partially restored TAM recruitment and tumor progression. Together, this study links hypoxia-induced epitranscriptomic changes to the emergence of an immunosuppressive microenvironment facilitating tumor evasion. SIGNIFICANCE: Hypoxia induces tumor immune microenvironment remodeling through an ALKBH5-mediated epigenetic and epitranscriptomic mechanism, providing potential immunotherapeutic strategies for treating glioblastoma.

Viscoelasticity of 3D actin networks dictated by the mechanochemical characteristics of cross-linkers

In this study, we report a computational investigation on how the mechanochemical characteristics of crosslinking molecules influence the viscoelasticity of three dimensional F-actin networks, an issue of key interest in analyzing the behavior of living cells and biological gels. In particular, it was found that the continuous breakage and rebinding of cross-linkers result in a locally peaked loss modulus in the rheology spectrum of the network, reflecting the fact that maximum energy dissipation is achieved when the driving frequency of the applied oscillating shear becomes comparable to the dissociation/association rate of crosslinking molecules. In addition, we showed that when subjected to constant rate of shear, an actin network can exhibit either strain hardening or softening depending on the ratio between the loading rate and unbinding speed of cross-linkers. A criterion for predicting the transition from softening to hardening was also obtained, in agreement with recent experiments. Finally, significant structural evolution was found to occur in random networks undergoing mechanical "training" (i.e. under a constant applied shear stress over a period of time), eventually leading to a pronounced anisotropic response of the network afterward which again is consistent with experimental observations.

Connectomic mapping of brain-spinal cord neural networks: future directions in assessing spinal cord injury at rest

Following spinal cord injury (SCI), the central nervous system undergoes significant reconstruction. The dynamic change in the interaction of the brain-spinal cord axis as well as in structure-function relations plays a vital role in the determination of neurological functions, which might have important clinical implications for the treatment and its efficacy evaluation of patients with SCI. Brain connectomes based on neuroimaging data is a relatively new field of research that maps the brain's large-scale structural and functional networks at rest. Importantly, increasing evidence shows that such resting-state signals can also be seen in the spinal cord. In the present review, we focus on the reconstruction of multi-level neural circuits after SCI. We also describe how the connectome concept could further our understanding of neuroplasticity after SCI. We propose that mapping the cortical-subcortical-spinal cord networks can provide novel insights into the pathologies of SCI.

Sustainable bio-bricks prepared with synthetic urine enabled by biomineralization reactions

In this study, mineralization during brick preparation was performed with ureolytic bacterium, Lysinibacillus fusiformis that use urine as a substrate, omitting the heat that is normally required. Artificial urine for reasons of standardization was used to grow the bacterium for bio-bricks made of clay and cement, but their mineralization was enabled by biological activity instead of by heat. Scanning electron microscopy and energy dispersion X-ray spectroscopy were conducted to analyse the microstructures formed by L. fusiformis that precipitated various minerals in synthetic urine. The brick specimens were tested for compressive strength that was 59% more than control ones, whereas porosity of bio-bricks was 13% compared to 22% of control specimens. The minerals formed in the bio-bricks confirmed as struvite, apatite and calcite by Fourier-transform infrared spectroscopy and X-ray diffraction spectra, were responsible for improved strength and reduced porosity. The research provided evidence in utilizing ureolytic bacteria as a mode to mineralize clay in brick production with the use of (artificial) urine as a substrate.

Pro-inflammatory and proliferative microglia drive progression of glioblastoma

Scant understanding of the glioblastoma microenvironment and molecular bases hampers development of efficient treatment strategies. Analyses of gene signatures of human gliomas demonstrate that the SETD2 mutation is correlated with poor prognosis of IDH1/2 wild-type (IDH-WT) adult glioblastoma patients. To better understand the crosstalk between SETD2 mutant (SETD2-mut) glioblastoma cells and the tumor microenvironment, we leverage single-cell transcriptomics to comprehensively map cellular populations in glioblastoma. In this study, we identify a specific subtype of high-grade glioma-associated microglia (HGG-AM). Further analysis shows that transforming growth factor (TGF)-β1 derived from SETD2-mut/IDH-WT tumor cells activates HGG-AM, exhibiting pro-inflammation and proliferation signatures. Particularly, HGG-AM secretes interleukin (IL)-1β via the apolipoprotein E (ApoE)-mediated NLRP1 inflammasome, thereby promoting tumor progression. HGG-AM present extensive proliferation and infiltration to supplement the activated microglia pool. Notably, TGF-β1/TβRI depletion dramatically reduces HGG-AM density and suppresses tumor growth. Altogether, our studies identify a specific microglia subpopulation and establish the cellular basis of interactions between HGG-AM and glioblastoma cells.

Geolocation Inference of Forensic Individual Origin by Soil Metagenomic Analysis

Abstract

Objective To preliminarily discuss the feasibility of geolocation inference of forensic individual origin by soil metagenomic analysis. Methods The 33 soil samples from Heilongjiang, Qinghai and Tibet were collected, total bacterial DNA in the samples were extracted, and universal primers were used to amplify the V3 and V4 hypervariable region of bacterial 16S rDNA. The region was sequenced by high-throughput sequencing （HTS） with the MiSeq sequencer. Bioinformatics analysis such as species composition and sample comparison was performed on sequencing data. The richness index and diversity index were calculated based on operational taxonomic unit （OTU） results. Results A total of 2 720 149 sequences were generated by sequencing. Those sequences were clustered into 114 848 OTUs. The Chao1 indexes of soil microorganisms in Heilongjiang, Qinghai, and Tibet were 797.45, 745.11 and 535.98, respectively, and Shannon indexes were 6.46, 6.36 and 6.25, respectively. The number of bacterial species and the community diversity in the soil from high to low were Heilongjiang > Qinghai > Tibet. The composition of soil bacteria in three provinces at various classification levels were obtained, the dominant genuses in Heilongjiang were Chthoniobacteraceae DA101 and an unannotated genus of Thermogemmatisporaceae; the dominant genuses in Qinghai were an unannotated genus of Cytophagaceae and an unannotated genus of Nocardioidaceae; the dominant genuses in Tibet were an unannotated genus of Comamonadaceae and Verrucomicrobiaceae Luteolibacter. The results of principal co-ordinates analysis demonstrated that, according to the weighted UniFrac analysis, the three principle components represented 56.36% of the total variable, and according to the unweighted UniFrac analysis, the three principle components represented 34.81% of the total variable. The samples from the same province could be clustered together, and the species and content of soil microorganisms from different provinces were significantly different. Conclusion Based on the metagenomic analysis method, soil samples from different regions can be effectively distinguished, which has potential application value in geolocation inference of forensic individual origin in the future.

Identification and characterization of N6-methyladenosine modification of circRNAs in glioblastoma

This research systematically profiled the global N6‐methyladenosine modification pattern of circular RNAs (circRNAs) in glioblastoma (GBM). Based on RNA methylation sequencing (MeRIP sequencing or N6‐methyladenosine sequencing) and RNA sequencing, we described the N6‐methyladenosine modification status and gene expression of circRNAs in GBM and normal brain tissues. N6‐methyladenosine–related circRNAs were immunoprecipitated and validated by real‐time quantitative PCR. Bioinformatics analysis and related screening were carried out. Compared with those of the NC group, the circRNAs from GBM exhibited 1370 new N6‐methyladenosine peaks and 1322 missing N6‐methyladenosine peaks. Among the loci associated with altered N6‐methyladenosine peaks, 1298 were up‐regulated and 1905 were down‐regulated. The N6‐methyladenosine level tended to be positively correlated with circRNA expression. Bioinformatics analysis was used to predict the biological function of N6‐methyladenosine–modified circRNAs and the corresponding signalling pathways. In addition, through PCR validation combined with clinical data mining, we identified five molecules of interest (BUB1, C1S, DTHD1, F13A1 and NDC80) that could be initial candidates for further study of the function and mechanism of N6‐methyladenosine–mediated GBM development. In conclusion, our findings demonstrated the N6‐methyladenosine modification pattern of circRNAs in human GBM, revealing the possible roles of N6‐methyladenosine–mediated novel noncoding RNAs in the origin and progression of GBM.

Safety and efficacy of irreversible electroporation treatment in hepatobiliary and pancreatic tumours: a single-centre experience

AIM

To report initial experience with irreversible electroporation (IRE) in a single tertiary oncology centre and to describe its role in the management of liver and pancreatic tumours.

MATERIALS AND METHODS

The present study was a retrospective review of the technical success rate, complications, and treatment efficacy of patients who had undergone IRE treatment for hepatobiliary and pancreatic tumours between February 2014 to January 2020. The patients were divided into two cohorts: first 30 patients (cohort A) and subsequent 70 patients (cohort B) after a change in protocol.

RESULTS

One hundred IRE procedures (n=69 liver lesions; n=28 pancreatic lesions, n=3 nodal disease) were reviewed. The overall technical success rate was 99%. Early and immediate complications were 4% and 3%, respectively. In cohort A, the complete tumour ablation rate was 65% (13/20) for hepatic tumours, 20% (1/5) for locally advanced pancreatic adenocarcinoma, 50% (2/4) for pancreatic neuroendocrine tumours, and 0% (0/1) for nodal metastasis. For cohort B, the rate improved to 87.76% (43/49) for hepatic tumours, 28.57% (4/14) for locally advanced pancreatic adenocarcinoma, 80% (4/5) for pancreatic neuroendocrine, and 50% (1/2) for nodal metastasis. After the initial cohort A, cohort B showed a significant increase in the initial complete ablation rate in hepatic tumours (p=0.028).

CONCLUSION

IRE is a complex technique with a steep learning curve. It is safe, effective, and is valuable in the treatment of liver tumours that are unsuitable or considered high risk for conventional thermal ablation. Its role in the management of pancreatic tumours is less clear and requires larger studies.

PTRF/cavin-1 remodels phospholipid metabolism to promote tumor proliferation and suppress immune responses in glioblastoma by stabilizing cPLA2

BACKGROUND

Metabolism remodeling is a hallmark of glioblastoma (GBM) that regulates tumor proliferation and the immune microenvironment. Previous studies have reported that increased polymerase 1 and transcript release factor (PTRF) levels are associated with a worse prognosis in glioma patients. However, the biological role and the molecular mechanism of PTRF in GBM metabolism remain unclear.

METHODS

The relationship between PTRF and lipid metabolism in GBM was detected by nontargeted metabolomics profiling and subsequent lipidomics analysis. Western blotting, quantitative real-time PCR, and immunoprecipitation were conducted to explore the molecular mechanism of PTRF in lipid metabolism. A sequence of in vitro and in vivo experiments (both xenograft tumor and intracranial tumor mouse models) were used to detect the tumor-specific impacts of PTRF.

RESULTS

Here, we show that PTRF triggers a cytoplasmic phospholipase A2 (cPLA2)-mediated phospholipid remodeling pathway that promotes GBM tumor proliferation and suppresses tumor immune responses. Research in primary cell lines from GBM patients revealed that cells overexpressing PTRF show increased cPLA2 activity-resulting from increased protein stability-and exhibit remodeled phospholipid composition. Subsequent experiments revealed that PTRF overexpression alters the endocytosis capacity and energy metabolism of GBM cells. Finally, in GBM xenograft and intracranial tumor mouse models, we showed that inhibiting cPLA2 activity blocks tumor proliferation and prevents PTRF-induced reduction in CD8+ tumor-infiltrating lymphocytes.

CONCLUSIONS

The PTRF-cPLA2 lipid remodeling pathway promotes tumor proliferation and suppresses immune responses in GBM. In addition, our findings highlight multiple new therapeutic targets for GBM.

LncRNA PRADX-mediated recruitment of PRC2/DDX5 complex suppresses UBXN1 expression and activates NF-κB activity, promoting tumorigenesis

Rationale: Accumulating evidence indicates that long noncoding RNAs (lncRNAs) play crucial roles in cancer progression; however, only few have been characterized in detail. The current study aimed to identify a novel cancer driver lncRNA in glioblastoma and colon adenocarcinoma.

Methods: We performed whole transcriptome analysis of TCGA pan-cancer datasets to compare the lncRNA expression profiles of tumor and paired normal tissues. In situ hybridization of tissue sections was performed to validate the expression data and determine the localization of lncRNAs that may be linked to glioblastoma and colon adenocarcinoma. Chromatin isolation by RNA purification (ChIRP), chromatin immunoprecipitation (ChIP), and Co-immunoprecipitation (Co-IP) assays were performed to assess the interaction between lncRNA, proteins, and chromatin. The functional significance of the identified lncRNAs was verified in vitro and in vivo by knockdown or exogenous expression experiments.

Results: We found a lncRNA ENST00000449248.1 termed PRC2 and DDX5 associated lncRNA (PRADX) that is highly expressed in glioblastoma and colon adenocarcinoma cells and tissues. PRADX, mainly located in the nucleus of tumor cells, could bind to EZH2 protein via the 5' terminal sequence. Moreover, PRADX increased the trimethylation of H3K27 in the UBXN1 gene promoter via PRC2/DDX5 complex recruitment and promoted NF-κB activity through UBXN1 suppression. Knockdown of PRADX significantly inhibited tumor cell viability and clonogenic growth in vitro. In xenograft models, PRADX knockdown suppressed tumor growth and tumorigenesis and prolonged the survival of tumor-bearing mice.

Conclusions: PRADX acts as a cancer driver and may serve as a potential therapeutic target for glioblastoma and colon adenocarcinoma.

Intestinal epithelium-derived BATF3 promotes colitis-associated colon cancer through facilitating CXCL5-mediated neutrophils recruitment

Inflammation is a critical player in the development and progression of colon cancer. Basic leucine zipper transcription factor ATF-like 3 (BATF3) plays an important role in infection and tumor immunity through regulating the development of conventional type 1 dendritic cells (cDC1s). However, the function of BATF3 in colitis and colitis-associated colon cancer (CAC) remains unclear. Here, BATF3 wild-type and knockout mice were used to construct an AOM/DSS-induced CAC model. In addition, DSS-induced chronic colitis, bone marrow cross-transfusion (BMT), neutrophil knockout, and other animal models were used for in-depth research. We found that BATF3 deficiency in intestinal epithelial cells rather than in cDC1s inhibited CAC, which was depended on inflammatory stimulation. Mechanistically, BATF3 directly promoted transcription of CXCL5 by forming a heterodimer with JunD, and accelerated the recruitment of neutrophils through the CXCL5-CXCR2 axis, ultimately increasing the occurrence and development of CAC. Tissue microarray and TCGA data also indicated that high expression of BATF3 was positively correlated with poor prognosis of colorectal cancer and other inflammation-related tumors. In summary, our results demonstrate that intestinal epithelial-derived BATF3 relies on inflammatory stimulation to promote CAC, and BATF3 is expected to be a novel diagnostic indicator for colitis and CAC.

Predictors of plaque erosion in current smokers and non-current smokers presented with ST-segment elevation myocardial infarction: an optical coherence tomography study

Background

Plaque erosion with subsequent coronary thrombosis is considered as an important cause of ST-segment elevation myocardial infarction (STEMI). Smoking is a major risk factor for acute coronary thrombosis. However, the relationship between current smoking status and plaque erosion has not been systematically investigated.

Purpose

The present study aimed to investigate predictors of plaque erosion in current smokers and non-current smokers with STEMI by using optical coherence tomography (OCT).

Methods

Between January 2015 to December 2017, a total of 1313 STEMI patients underwent pre-intervention OCT of culprit lesion were enrolled and divided into two groups based on current smoking status: current smoking group (n=713) and non-current smoking group (n=600). Using established criteria, quantitative and qualitative underlying plaque characteristics were assessed by OCT. Clinical, angiographic and OCT characteristics of all enrolled patients were recorded. Univariable and multivariable logistic regression analyses were used to identify predictors of plaque erosion in two groups.

Results

Plaque erosion were found in 30.9% (220/713) culprit lesions in current smoking group and 20.8% (125/600) of those in non-current smoking group detected by OCT. In multivariate regression analysis, the predictors that strongly related to plaque erosion in the current smoking group were nearby bifurcation (OR: 4.84; 95% CI:2.38–9.87; p&lt;0.001); the minimum fiber cap thickness (FCT, OR:1.05; 95% CI:1.03–1.08; p&lt;0.001); thin-cap fibroatheroma (TCFA, OR: 0.22; 95% CI: 0.07–0.67; p=0.007) and lipid core length (OR: 0.91; 95% CI: 0.84–0.97; p=0.007). The predictors in the non-current smoking group were nearby bifurcation (OR: 4.84; 95% CI: 2.38–9.87; p=0.006); the minimal FCT (OR: 1.09; 95% CI: 1.06–1.13; p&lt;0.001); multi-vessel disease (MVD, OR: 0.43; 95% CI: 0.19–0.97; p=0.042) and dyslipidemia (OR: 0.34; 95% CI: 0.14–0.84; p=0.020).

Conclusions

Predictors of plaque erosion causing STEMI onset are different between current smokers and non-current smoker, with nearby bifurcation and thicker minimal FCT both predicting plaque erosion in two groups of patients.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Key Research and Development Program of China, National Natural Science Foundation of China.

Coronary plaque characteristics associated with reduced thrombolysis in myocardial infarction flow in st-segment elevation myocardial infarction patients with plaque erosion

Background

It has been reported that the lumen factors of the culprit lesions are related to Thrombolysis in Myocardial Infarction (TIMI) flow grade in ST-Segment–Elevation Myocardial Infarction (STEMI) patients, but the factors of reduced TIMI flow in plaque erosion have not been studied.

Methods

329 STEMI patients with plaque erosion who underwent pre-intervention optical coherence tomography after thrombectomy were included and divided into 2 groups according to preprocedural TIMI flow grade [TIMI 0–1 (n=219) and TIMI 2–3 (n=110)].

Results

The patients with older age (55.7±11.1yrs vs. 51.8±10.6yrs, P=0.003) and diabetes patients (18.3% vs. 8.2%, P=0.015) had poorer TIMI flow, and the patients with reduced TIMI flow grade have lower initial cTnI (1.2ng/mL vs. 2.1ng/mL, P=0.023). The lesion in the LAD had better blood flow than the lesion in RCA (P=0.003), and the patients in TIMI 0–1 grade had more lipid plaques (53.9% vs. 41.8%, P=0.039), more macrophage (59.8% vs. 41.8%, P=0.002), and more calcification (34.2% vs. 21.8%, P=0.020). There was no statistically significant difference in the descriptive indicators of lipid or lumen between the two groups. And In a multivariate logistic regression model, the independent correlation factors of reduced TIMI flow grade in erosion patients were age, diabetes mellitus, lesion vessel, and macrophage.

Conclusions

In STEMI patients with plaque erosion non-lumen factors greatly affect flow, which suggests that systemic treatment is as important as local treatment for plaque erosion.

Flow Chart

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Natural Science Foundation of China (81827806, 81801861), National Key R&D Program of China (2016YFC1301100)

Morphological characteristics of plaque erosion with noncritical coronary stenosis: an optical coherence tomography study

Background

Plaque erosion is a frequent and important mechanism of acute coronary thrombosis only secondary to plaque rupture. Recent studies suggested plaque erosion with noncritical stenosis could be treated conservatively that distinct from those with critical stenosis. However, characteristics of plaque erosions with different coronary stenosis remain unknown.

Purpose

The present study aimed to investigate morphological features of plaque erosions with different coronary stenosis using optical coherence tomography (OCT).

Methods

Consecutive ST-segment elevated myocardial infarction (STEMI) patients with OCT images of culprit lesion between August 2014 and December 2017 were enrolled and 348 cases presented with plaque erosion identified by OCT. Based on the severity of lumen area stenosis [calculated by (1-minimal lumen area/reference lumen area) * 100%], all culprit plaque erosions were divided into three groups: Group A (area stenosis&lt;50%, n=50, 14.4%); Group B (50%≤area stenosis&lt;75%, n=146, 42.0%); Group C (area stenosis≥75%, n=152, 43.7%). Clinical characteristics, lesion features detected by coronary angiography and OCT were compared among three groups.

Results

Of all 348 STEMI patients with plaque erosions, patients in Group A were youngest (p=0.008) and had the lowest frequency of hypertension (p=0.029) as compared with those in Group B and C. Angiographic analysis showed 72.0% of plaque erosions in Group A located in LAD, while 67.8% in Group B and 53.9% in Group C (p=0.039). OCT findings (Figure 1-A) showed the prevalence of fibrous plaque was significantly highest in Group A than those in Group B and C (82.0% vs. 54.8% vs. 34.9%, p&lt;0.001), whereas lipid rich plaque was most frequent in Group C (16.0% vs. 43.8% vs. 62.5%, p&lt;0.001). The prevalence of macrophage (p&lt;0.001), microvessel (p=0.009) and cholesterol crystals (p&lt;0.001) increased gradually from plaque erosion with lumen area stenosis &lt;50% to 50–75% to ≥75%. Notably, compared with Group B and C, nearby bifurcation was most common in Group A (72.0% vs. 67.1% vs. 55.3%, p=0.036). Multivariable regression analyses (Figure 1-B) showed fibrous plaque and nearby bifurcation were independently associated with plaque erosion with noncritical stenosis (area stenosis&lt;75%).

Conclusion

56.3% plaque erosion in STEMI patients presented with noncritical stenosis, having distinct morphological features from erosion with critical stenosis. Fibrous plaque and nearby bifurcation were independently associated with the presence of noncritically stenotic plaque erosion, remaining a desire to tailor treatment therapy to individual patients.

Figure 1

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Key R&D Program of China

Relation of microchannel identified by optical coherence tomography to clinical, angiography and other plaque morphological characteristics in ST-segment Elevation myocardial infarction patients

Background

Previous studies have suggested that Microchannel (MC) is associated with plaque progression and vulnerability. Optical coherence tomography (OCT) could provide a chance to directly visualize plaque neovascularization in vivo.

Methods

1268 STEMI patients who underwent OCT examination of culprit lesion were included and divided into MC group (the culprit plaque with MC, n=560) and no-MC group (the culprit plaque without MC, n=708). MC was defined as a no-signal tubuloluminal structure on the cross-sectional optical coherence tomographic image. Clinical, angiography and other plaque morphological characteristics were compared between the two groups. Logistic regression analysis was used to identify independent predictors of MC in overall. In addition, the difference of predictors on MC was found in plaque rupture (PR) and plaque erosion (PE).

Results

Significant differences between MC group and no-MC group were found in the frequency of thin-cap fibroatheroma (74.6% vs 64.4%, p&lt;0.001), lipid plaque (91.8% vs 82.9%, p&lt;0.001), lipid core length (13.7±6.5mm vs 12.6±6.3mm, p=0.006) and the minimal lumen area (MLA, 1.95±0.98mm2 vs 2.10±1.58mm2, p=0.046). In MC group, the other vulnerable plaque morphological characteristics, such as macrophage (88.8% vs 75.1%, p&lt;0.001), cholesterol crystal (39.6% vs 32.9%, p=0.013), spotty calcification (38.6% vs 29.5%, p&lt;0.001) were more frequent. And compared with MLA the more locations of the culprit lesion in MC group was proximal (proximal, 47.3% vs 38.1%, at MLA, 38.2% vs 44.2%, distal, 14.5% vs 17.7%, p=0.004).The difference of Hemoglobin (Hb, 147.5±16.9g/L vs 144.1±18.2g/L, p&lt;0.001), lipidemia (TC, 188.7±43.6mmol/L vs 180.8±40.0mmol/L, p&lt;0.001, LDL-C, 121.5±37.4mmol/L vs 115.7±36.8mmol/L, p=0.005, and TC/HDL, 4.0±1.6 vs 3.8±1.0, p&lt;0.001), and hypertension (50.7% vs 44.2%, p=0.021) between 2 groups was statistically significant. Multivariable logistic regression models showed 7 independent parameters associated with MC in culprit plaque of overall: hypertension, Hb, TC, MLA, lesion location (compared with MLA), lipid core length, macrophage, spotty calcification. In addition, Hb, TC and MLA were common predictors of MC in PR and PE, however, the predictive effect of MLA on MC was opposite in PR [OR (95% CI)=1.266 (1.095–1.463), p=0.001] and PE [OR (95% CI)=0.742 (0.597–0.922), p=0.007].

Conclusions

MC in culprit plaque is associated with more lipid (especially cholesterol), higher Hb, hypertension, lesion location (compared with MLA) and the other vulnerable plaque morphological characteristics. The predictors of MC were different in plaque rupture and plaque erosion.

Flow chart

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Natural Science Foundation of China (81827806, 81801861); National Key R&D Program of China (2016YFC1301100)

Effect of TTLL12 on tubulin tyrosine nitration as a novel target for screening anticancer drugs in vitro

Nitrotyrosine, a structural analogue of tyrosine, is present in cells in pathological conditions and is incorporated into tubulin to form tubulin tyrosine nitration, which disrupts the normal function of microtubules. There is limited research on the functional aspects of tubulin tyrosine nitration in different types of tumor. In the present study, the effect of tubulin tyrosine nitration and tubulin tyrosine ligase like 12 (TTLL12) on the proliferation of SCC-25 cells was investigated. TTLL12-overexpressing cell lines were constructed and used to assess the effect of tubulin tyrosine nitration and TTLL12 on the proliferation of SCC-25 cells via western blotting, immunofluorescent and MTT assays. An TTLL12-stably overexpressing SCC-25 cell line and the enzyme-linked immunosorbent assay were used to establish a novel experiment in vitro for screening anticancer drugs targeting tubulin tyrosine nitration by assessing its sensitivity, specificity and repeatability, and using it to find an effective drug. The results demonstrated that the proliferative rate of the control cells was notably inhibited in the presence of nitrotyrosine compared with that of TTLL12-overexpressing cells. The results of the MTT assay revealed that the proliferation of TTLL12-silenced cells was significantly inhibited compared with that of the control group. The sensitivity, specificity and repeatability of the experiment were positive. It was found that nocodazole could have better anticancer effect than paclitaxel. Taken together, the results of the present study suggest that TTLL12 enhances SCC-25 cell survival in the presence of nitrotyrosine by disrupting nitration of the tyrosine residues of tubulin, and tubulin tyrosine nitration may be developed for the basic research of anticancer drugs.

Prevalence of hypoxia and correlation with glycolytic metabolism and angiogenic biomarkers in metastatic colorectal carcinoma

PURPOSE

Hypoxia is associated with aggressive tumour behaviour and can influence response to systemic therapy and radiotherapy. The prevalence of hypoxia in metastatic colorectal cancer is poorly understood, and the relationship of hypoxia to patient outcomes has not been clearly established. The aims of the study were to evaluate hypoxia in metastatic colorectal cancer with [¹⁸F]Fluoromisonidazole ([¹⁸F]FMISO PET) and correlate these findings with glycolytic metabolism ([¹⁸F]FDG PET) and angiogenic blood biomarkers and patient outcomes.

METHODS

Patients with metastatic colorectal cancer received routine staging investigations and both [¹⁸F] FMISO PET and [¹⁸F] FDG PET scans. Correlative blood specimens were also obtained at the time of the [¹⁸F] FMISO PET scan. Patient follow-up was performed to establish progression-free survival.

RESULTS

A total of 40 patients were recruited into the trial. [¹⁸F]FMISO and [¹⁸F]FDG PET scans showed a significant correlation of SUV_max (p = 0.003). A significant correlation of progression-free survival and [¹⁸F] FMISO TNR (p = 0.02) and overall survival with [¹⁸F]FMISO TNR (p = 0.003) and [¹⁸F]FDG TGV (p = 0.02) was observed. Serum levels of osteopontin, but not VEGF, correlated with [¹⁸F] FMISO and [¹⁸F]FDG PET scan parameters.

CONCLUSION

[¹⁸F]FMISO PET uptake in metastatic colorectal cancer significantly correlates with glycolytic metabolism and is predictive of progression-free and overall survival. These findings have implications for the assessment and treatment of metastatic colorectal cancer patients with novel therapies which affect tumour angiogenesis and hypoxia.

Extent of pulmonary thromboembolic disease in patients with COVID-19 on CT: relationship with pulmonary parenchymal disease

AIM

To report the severity and extent of pulmonary thromboembolic disease (PTD) in COVID-19 patients undergoing computed tomography pulmonary angiography (CTPA) in a tertiary centre.

MATERIALS AND METHODS

This is a retrospective analysis of COVID-19 patients undergoing CTPA over a period of 27 days. The presence, extent, and severity of PTD were documented. Two observers scored the pattern and extent of lung parenchymal disease including potential fibrotic features, as well as lymph node enlargement and pleural effusions. Consensus was achieved via a third observer. Interobserver agreement was assessed using kappa statistics. Student's t-test, chi-squared, and Mann-Whitney U-tests were used to compare imaging features between PTD and non-PTD sub-groups.

RESULTS

During the study period, 100 patients with confirmed COVID-19 underwent CTPA imaging. Ninety-three studies were analysed, excluding indeterminate CTPA examinations. Overall incidence of PTD was 41/93 (44%) with 28/93 patients showing small vessel PTD (30%). D-dimer was elevated in 90/93 (96.8%) cases. A high Wells' score did not differentiate between PTD and non-PTD groups (p=0.801). The interobserver agreement was fair (kappa=0.659) for parenchymal patterns and excellent (kappa=0.816) for severity. Thirty-four of the 93 cases (36.6%) had lymph node enlargement; 29/34 (85.3%) showed no additional source of infection. Sixteen of the 93 (17.2%) cases had potential fibrotic features.

CONCLUSION

There is a high incidence of PTD in COVID-19 patients undergoing CTPA and lack of a risk stratification tool. The present data indicates a higher suspicion of PTD is needed in severe COVID-19 patients. The concomitant presence of possible fibrotic features on CT indicates the need for follow-up.

m6A modification in RNA: biogenesis, functions and roles in gliomas

The chemical modification of RNA is a newly discovered epigenetic regulation mechanism in cells and plays a crucial role in a variety of biological processes. N6-methyladenine (m6A) mRNA modification is the most abundant form of posttranscriptional RNA modification in eukaryotes. Through the development of m6A RNA sequencing, the relevant molecular mechanism of m6A modification has gradually been revealed. It has been found that the effect of m6A modification on RNA metabolism involves processing, nuclear export, translation and even decay. As the most common malignant tumour of the central nervous system, gliomas (especially glioblastoma) have a very poor prognosis, and treatment efficacy is not ideal even with the application of high-intensity treatment measures of surgery combined with chemoradiotherapy. Exploring the origin and development mechanisms of tumour cells from the perspective of tumour biogenesis has always been a hotspot in the field of glioma research. Emerging evidence suggests that m6A modification can play a key role in gliomas through a variety of mechanisms, providing more possibilities for early diagnosis and targeted therapy of gliomas. The aim of the present review is to focus on the research progress regarding the association between m6A modification and gliomas. And to provide a theoretical basis according to the currently available literature for further exploring this association. This review may provide new insights for the molecular mechanism, early diagnosis, histologic grading, targeted therapy and prognostic evaluation of gliomas.