Objective·To investigate the differential gene expression of microglia in the gray and white matter of multiple sclerosis(MS)using single-nucleus transcriptomic analysis,aiming to explore their roles in disease progression,and identify key transcriptional regulatory networks associated with the disease.Methods·snRNA-seq data of frozen human brain tissue samples from MS patients and control individuals were obtained from the Gene Expression Omnibus(GEO)database.R language,along with R packages such as Seurat,was employed to identify cell types based on specific cell markers.Microglia were extracted from the identified cell populations and classified based on their anatomical origin,either gray matter or white matter.Dimensionality reduction and clustering techniques were utilized to identify distinct microglial subpopulations with differential characteristics.Differentially expressed genes(DEGs)between the MS and control groups at the subpopulation level were analyzed by using the Seurat package.Gene set enrichment analysis of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)was conducted on the DEGs to further explore the biological significance of these differences.Monocle3 was used for pseudotime analysis to study dynamic changes in microglia subpopulations during disease progression.Single cell regulatory network inference and clustering(SCENIC)method was applied to analyze transcription factor(TF)regulatory networks,aiming to identify key transcription factors potentially involved in MS regulation.Results·After quality control,a total of 149 062 nuclei were retained for analysis.Following dimensional reduction and clustering,12 238 microglia were identified by using key markers,including DOCK8,CSF1R,P2RY12,and CD74.The results of GO and KEGG pathway analysis showed that in gray matter microglia,functions such as endocytosis,ion homeostasis,and lipid localization were downregulated during disease progression,while in white matter microglia,functions such as protein folding,cytoplasmic translation,and response to thermal stimuli were upregulated.SCENIC analysis revealed that the expression of transcription factors such as FLI1,MITF,and FOXP1 was upregulated in MS.Conclusion·Microglia play a critical role in MS,with white matter microglia being more significantly impacted by MS than their gray matter counterparts.Transcription factors such as FLI1,MITF,and FOXP1 are identified as key regulators involved in disease modulation,with their associated transcriptional regulatory networks playing a central role in disease modulation.

Objective·To investigate the differential gene expression of microglia in the gray and white matter of multiple sclerosis(MS)using single-nucleus transcriptomic analysis,aiming to explore their roles in disease progression,and identify key transcriptional regulatory networks associated with the disease.Methods·snRNA-seq data of frozen human brain tissue samples from MS patients and control individuals were obtained from the Gene Expression Omnibus(GEO)database.R language,along with R packages such as Seurat,was employed to identify cell types based on specific cell markers.Microglia were extracted from the identified cell populations and classified based on their anatomical origin,either gray matter or white matter.Dimensionality reduction and clustering techniques were utilized to identify distinct microglial subpopulations with differential characteristics.Differentially expressed genes(DEGs)between the MS and control groups at the subpopulation level were analyzed by using the Seurat package.Gene set enrichment analysis of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)was conducted on the DEGs to further explore the biological significance of these differences.Monocle3 was used for pseudotime analysis to study dynamic changes in microglia subpopulations during disease progression.Single cell regulatory network inference and clustering(SCENIC)method was applied to analyze transcription factor(TF)regulatory networks,aiming to identify key transcription factors potentially involved in MS regulation.Results·After quality control,a total of 149 062 nuclei were retained for analysis.Following dimensional reduction and clustering,12 238 microglia were identified by using key markers,including DOCK8,CSF1R,P2RY12,and CD74.The results of GO and KEGG pathway analysis showed that in gray matter microglia,functions such as endocytosis,ion homeostasis,and lipid localization were downregulated during disease progression,while in white matter microglia,functions such as protein folding,cytoplasmic translation,and response to thermal stimuli were upregulated.SCENIC analysis revealed that the expression of transcription factors such as FLI1,MITF,and FOXP1 was upregulated in MS.Conclusion·Microglia play a critical role in MS,with white matter microglia being more significantly impacted by MS than their gray matter counterparts.Transcription factors such as FLI1,MITF,and FOXP1 are identified as key regulators involved in disease modulation,with their associated transcriptional regulatory networks playing a central role in disease modulation.

Hepatocellular carcinoma (HCC), which makes up the majority of liver cancer, is induced by the infection of hepatitis B/C virus. Biomarkers are needed to facilitate the early detection of HCC, which is often diagnosed too late for effective therapy. The tRNA-derived small RNAs (tsRNAs) play vital roles in tumorigenesis and are stable in circulation. However, the diagnostic values and biological functions of circulating tsRNAs, especially for HCC, are still unknown. In this study, we first utilized RNA sequencing followed by quantitative reverse-transcription PCR to analyze tsRNA signatures in HCC serum. We identified tRF-Gln-TTG-006, which was remarkably upregulated in HCC serum (training cohort: 24 HCC patients vs. 24 healthy controls). In the validation stage, we found that tRF-Gln-TTG-006 signature could distinguish HCC cases from healthy subjects with high sensitivity (80.4%) and specificity (79.4%) even in the early stage (Stage I: sensitivity, 79.0%; specificity, 74.8%; 155 healthy controls vs. 153 HCC patients from two cohorts). Moreover, in vitro studies indicated that circulating tRF-Gln-TTG-006 was released from tumor cells, and its biological function was predicted by bioinformatics assay and validated by colony formation and apoptosis assays. In summary, our study demonstrated that serum tsRNA signature may serve as a novel biomarker of HCC.
Biomarkers ; Biomarkers, Tumor/genetics* ; Carcinoma, Hepatocellular/diagnosis* ; Hepatitis B virus ; Humans ; Liver Neoplasms/diagnosis* ; RNA, Transfer/genetics*

Aneurysmal subarachnoid hemorrhage (aSAH) isa cerebrovascular event with serious health consequences and is characterized by a high incidence,high morbidity,high mortality and high recurrence rate.As global population aging intensifies,the prognosis of aSAH among the elderly has become a focus for researchers in various specialties.Consequently,the identification of risk factors for the prognosis of aSAH in the elderly carries enormous importance.In this article,we review the recent advances in factors and the genetics related to the prognosis of aSAHin elderly patients.