Objective To map the genome-wide distribution profile of histone H3K27me3 modification in diffuse gastric cancer tissues,identify target genes regulated by H3K27me3,and primarily explore the potential mechanism of its modification reprogramming in the occurrence and development of the tumor.Methods Normal gastric mucosal tissues and diffuse gastric cancer tissues were harvested from the patients who underwent examinations or treatments in the departments of gastroenterology and gastrointestinal surgery of our medical center between 2021 and 2023.There were 14 patients in the normal group(6 males and 8 females,average age of 46 years)and 14 patients in the gastric cancer group(8 males and 6 females,average age of 63 years).Cleavage under target and tagmentation(CUT&Tag)technology was employed to capture genomic regions modified by H3K27me3,and analyze the reprogramming characteristics of these modifications.RNA sequencing data,data from high-throughput chromosome conformation capture(Hi-C)technology,and publicly available single-cell data were integrated to investigate the target genes regulated by the reprogramming of H3K27me3 modifications in diffuse gastric cancer cells.Results The quality of the CUT&Tag and RNA sequencing data met the standards required for subsequent analysis.Histone H3K27me3 modifications in normal gastric mucosa and diffuse gastric cancer tissues were primarily distributed in distal intergenic regions and intronic regions.In gastric cancer tissues,compared to normal tissues,there was significant reprogramming of H3K27me3 modifications,characterized by a marked reduction in overall H3K27me3 signal intensity.The loss of 2 912 H3K27me3 signal peaks might lead to the up-regulation of 822 tumor-associated genes.Among them,56 genes displayed the most significant up-regulation(fold change in signal intensity≥2,P<0.05),with notable enrichment in the mammalian target of rapamycin complex 1(mTORC1)signaling pathway.Specifically,the methionine transporter SLC7A5 and the cystine transporter SLC7A11 were found to have the highest expression levels in gastric cancer tissues.Single-cell data revealed that the abnormal overexpression of SLC7A11 in diffuse gastric cancer was primarily observed in tumor epithelial cells.Further validation using public data and immunohistochemical experiments confirmed the elevated expression of SLC7A11 in diffuse gastric cancer,which is associated with poor prognosis in gastric cancer patients.Conclusion The reprogramming of histone H3K27me3 modification is an important epigenetic characteristic in diffuse gastric cancer.Loss of H3K27me3 signal peaks may up-regulate the expression of SLC7A11 in diffuse gastric cancer cells,and thereby promote tumor progression.

Objective To map the super-enhancers remodeling of intestinal gastric cancer and reveal the tumor biological functions of the super-enhancers and the downstream target genes that may be activated.Methods A total of 31 normal gastric mucosal tissues,23 intestinal gastric cancer tissues and 9 intestinal gastric cancer organoids were collected from the Department of Gastroenterology of Army Medical Center of PLA from January to December 2022.Chromatin targeting histone H3K27ac modified chromatin targeting cleavage under targets and tagmentation(CUT&Tag)sequencing was conducted on above tissues.The remodeling profiles of super-enhancers in intestinal gastric cancer were analyzed and the key target genes were identified based on bioinformation tools.CRISPRi technology was used to intervene with the super-enhancers,the expression of target genes was detected with Western blotting,and the proliferation,migration and invasion abilities were detected by CCK-8 assay and Transwell chambers in the control group and the intervention group.Results There was a significant difference in the signal of super-enhancers between intestinal gastric cancer tissues and normal gastric mucosal tissues(P<0.05),and the active super-enhancers in cancer tissues may be involved in biological processes such as negative regulation of the immune system and cell adhesion.The expression of up-regulated cell migration-inducing protein(CEMIP)in tumor cells was regulated by the super-enhancers,and intervening the super-enhancers down-regulated the expression of CEMIP(P<0.05),and inhibited the cell proliferation,invasion and migration abilities of tumor cells(P<0.05).Conclusion Super-enhancer remodeling is observed in intestinal gastric cancer,and they can up-regulate the expression of CEMIP gene and promote the growth,migration and invasion of cancer cells.

Objective To draw the genome-wide distribution and remodeling characteristics of H3K27me3 silencers in signet-ring cell carcinoma of the stomach(SRCC)through epigenetic sequencing technology,and to investigate their roles in transcriptional regulation in order to elucidate the regulatory mechanism of SRCC malignant progression.Methods The study was conducted on 35 gastric samples obtained by gastroendoscopic biopsy(15 normal and 20 SRCC tissues)from Department of Gastroenterology of Army Medical Center of PLA between January 2021 and December 2023.Multi-omics analyses,including assay for transposase-accessible chromatin with high-throughput sequencing(ATAC-seq),cleavage under targets and tagmentation(CUT&Tag)and transcriptome sequencing(RNA-seq),were performed to identify chromatin accessibility,H3K27me3 silencer regions,and transcriptional changes,with aid of Illumina NovaSeq 6000.H3K27me3 related differentially expressed genes(|Log2FC|>1,FDR<0.05)were screened using DESeq2.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were employed to analyze the enrichment function,and Homer was employed to identify transcription factor motifs.A regulatory network was constructed using Cytoscape,and then validated using immunohistochemistry to explore its regulatory mechanism.Results H3K27me3 silencers were primarily located in distal intergenic regions(37.06%)in SRCC.Compared with the normal tissues,SRCC showed a significant reduction in H3K27me3 silencer signals(95%CI:1.34～2.30,P=0.007)with 6 257 lost sites(FDR<0.01).Integrating CUT&Tag and RNA-seq revealed 380 up-regulated immune-related genes,particularly in T cell receptor signaling(OR=4.2,95%CI:2.8～6.3,P=0.002).Immunohistochemistry confirmed elevated expression of transcription factor EHF(P<0.05).Conclusion There is the remodeling of H3K27me3 silencers in SRCC,and EHF may potentially play a crucial role in the SRCC malignant progression.

Objective·To analyze the expression of mitochondrial related gene SFXN3(sideroflexin 3)in head and neck squamous cell carcinoma(HNSCC)and its effect on cell proliferation.Methods·Mitochondrial related genes and TCGA-HNSCC dataset were obtained from public databases to identify the target gene SFXN3 by using bioinformatic methods.The expression of SFXN3 in HNSCC patient samples was analysed by using the UALCAN database,and survival analyses of patients with different SFXN3 expression levels were performed according to TCGA-HNSCC cohort and GEO cohorts(GSE65858,GSE41613 and GSE27020).By using TCGA-HNSCC cohort and GEO cohorts(GSE40020,GSE210287),the differences in SFXN3 expression levels between therapeutic responders and non-responders were compared.Quantitative real-time PCR(qRT-PCR)was used to verify the expression of SFXN3 in the collected HNSCC tumor and para-tumor tissues,and the expression level of SFXN3 in human normal oral epithelial cells and HNSCC tumor cell lines was detected.With the construction of stable-SFXN3-knockdown HNSCC cell lines,the effect of SFXN3 on the proliferation ability of HNSCC cells was observed by using the Incucyte live-cell imaging analysis system and plate colony formation assay.Transcriptome sequencing was performed on the total RNA of stably-SFXN3-knockdown cells and control cells,and pathway enrichment analysis was performed on the genes with differentially down-regulated expression in knockdown group compared with control group.Results·SFXN3 was highly expressed in tumor tissues of HNSCC patients(P=0.000),and the prognosis of patients in the SFXN3-high-expression group was poor(all P＜0.05).The expression level of SFXN3 in the non-responders was higher than that in the responders(P=0.008),indicating an unfavorable prognosis.High expression of SFXN3 was verified in the collected HNSCC tumor tissues and HNSCC cell lines(all P＜0.05).After the knockdown of SFXN3 expression,the proliferation ability of HNSCC cells decreased,and the number of plate clones decreased(all P＜0.05).RNA sequencing showed that the differentially expressed down-regulated genes in HNSCC cells in the SFXN3-knockdown group were enriched in DNA replication,cell cycle,mitochondrial translation,mitochondrial RNA metabolic process and mitochondrial gene expression pathways.Conclusion·SFXN3 is highly expressed in HNSCC and it has negative correlation with the prognosis of patients.The proliferation ability and plate colony formation ability are inhibited in SFXN3-knockdown HNSCC cells,and these may work by affecting mitochondria function.

Objective To explore the genome-wide distribution of histone H3K27ac in intestinal type gastric cancer,analyze remodeling features of enhancers and regulome and construct a prediction model for prognosis.Methods H3K27ac CUT&Tag sequencing and RNA sequencing were performed in intestinal type gastric cancer tissues from 15 patients and normal gastric mucosa tissues from 18 healthy volunteers.Bioinformatics analysis was performed to identify the differences in genome distribution of H3K27ac modifications.Based on the distribution characteristics of H3K27ac,the enhancer elements were identified and the remodeling characteristics of enhancer and related regulome were explored.The prediction model for prognosis based on enhancer related target genes was constructed by univariate Cox and multivariate Cox regression analyses.Results The histone H3K27ac modification was mainly distributed in the enhancer region and displayed no significant differences in the genomic distribution patterns between normal and cancer tissues.Compared with normal gastric mucosa,the level of enhancer H3K27ac modification was higher in intestinal type gastric cancer.A total of 8847 enhancers with increased activity in intestinal type gastric cancer were identified,accounting for 8.3%of all enhancers,which might promote malignant behaviors such as proliferation and adhesion of gastric cancer cells.A prognosis-predicting model established based on a panel of 6 genes that upregulated by the acquired enhancer in cancers,which was able to predict the overall survival of patients.Conclusion Enhancer remodeling is one of the significant epigenetic features of intestinal type gastric cancer.These enhancers may drive malignant growth and adhesion of cancer cells by upregulating the expression of MYC,E2F3 and other genes.A prognosis model based on enhancer target genes is constructed.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting both upper and lower motor neurons in the brain and spinal cord. One important aspect of ALS pathogenesis is superoxide dismutase 1 (SOD1) mutant-mediated mitochondrial toxicity, leading to apoptosis in neurons. This study aimed to evaluate the neural protective synergistic effects of ginsenosides Rg1 (G-Rg1) and conditioned medium (CM) on a mutational SOD1 cell model, and to explore the underlying mechanisms. We found that the contents of nerve growth factor, glial cell line-derived neurotrophic factor, and brain-derived neurotrophic factor significantly increased in CM after human umbilical cord mesenchymal stem cells (hUCMSCs) were exposed to neuron differentiation reagents for seven days. CM or G-Rg1 decreased the apoptotic rate of SOD1^G93A-NSC34 cells to a certain extent, but their combination brought about the least apoptosis, compared with CM or G-Rg1 alone. Further research showed that the anti-apoptotic protein Bcl-2 was upregulated in all the treatment groups. Proteins associated with mitochondrial apoptotic pathways, such as Bax, caspase 9 (Cas-9), and cytochrome c (Cyt c), were downregulated. Furthermore, CM or G-Rg1 also inhibited the activation of the nuclear factor-kappa B (NF-κB) signaling pathway by reducing the phosphorylation of p65 and IκBα. CM/G-Rg1 or their combination also reduced the apoptotic rate induced by betulinic acid (BetA), an agonist of the NF-κB signaling pathway. In summary, the combination of CM and G-Rg1 effectively reduced the apoptosis of SOD1^G93A-NSC34 cells through suppressing the NF-κB/Bcl-2 signaling pathway (Fig. 1 is a graphical representation of the abstract).
Humans ; NF-kappa B/metabolism* ; Ginsenosides/pharmacology* ; Amyotrophic Lateral Sclerosis/genetics* ; Culture Media, Conditioned/pharmacology* ; Superoxide Dismutase-1 ; Neurodegenerative Diseases ; Neurons/metabolism* ; Apoptosis

The epitranscriptomic mark N⁶-methyladenosine (m⁶A), which is the predominant internal modification in RNA, is important for plant responses to diverse stresses. Multiple environmental stresses caused by the tea-withering process can greatly influence the accumulation of specialized metabolites and the formation of tea flavor. However, the effects of the m⁶A-mediated regulatory mechanism on flavor-related metabolic pathways in tea leaves remain relatively uncharacterized. We performed an integrated RNA methylome and transcriptome analysis to explore the m⁶A-mediated regulatory mechanism and its effects on flavonoid and terpenoid metabolism in tea (Camellia sinensis) leaves under solar-withering conditions. Dynamic changes in global m⁶A level in tea leaves were mainly controlled by two m⁶A erasers (CsALKBH4A and CsALKBH4B) during solar-withering treatments. Differentially methylated peak-associated genes following solar-withering treatments with different shading rates were assigned to terpenoid biosynthesis and spliceosome pathways. Further analyses indicated that CsALKBH4-driven RNA demethylation can directly affect the accumulation of volatile terpenoids by mediating the stability and abundance of terpenoid biosynthesis-related transcripts and also indirectly influence the flavonoid, catechin, and theaflavin contents by triggering alternative splicing-mediated regulation. Our findings revealed a novel layer of epitranscriptomic gene regulation in tea flavor-related metabolic pathways and established a link between the m⁶A-mediated regulatory mechanism and the formation of tea flavor under solar-withering conditions.
RNA/metabolism* ; Epigenome ; Plant Proteins/metabolism* ; Plant Leaves/metabolism* ; Camellia sinensis/metabolism* ; Flavonoids ; Terpenes/metabolism* ; Tea/metabolism* ; Gene Expression Regulation, Plant

Oolong tea is a semi-fermented tea with strong flavor, which is widely favored by consumers because of its floral and fruity aroma as well as fresh and mellow taste. During the processing of oolong tea, withering is the first indispensable process for improving flavor formation. However, the molecular mechanism that affects the flavor formation of oolong tea during withering remains unclear. Transcriptome sequencing was used to analyze the difference among the fresh leaves, indoor-withered leaves and solar-withered leaves of oolong tea. A total of 10 793 differentially expressed genes were identified from the three samples. KEGG enrichment analysis showed that the differentially expressed genes were mainly involved in flavonoid synthesis, terpenoid synthesis, plant hormone signal transduction and spliceosome pathways. Subsequently, twelve differentially expressed genes and four differential splicing genes were identified from the four enrichment pathways for fluorescence quantitative PCR analysis. The results showed that the expression patterns of the selected genes during withering were consistent with the results in the transcriptome datasets. Further analysis revealed that the transcriptional inhibition of flavonoid biosynthesis-related genes, the transcriptional enhancement of terpenoid biosynthesis-related genes, as well as the jasmonic acid signal transduction and the alternative splicing mechanism jointly contributed to the flavor formation of high floral and fruity aroma and low bitterness in solar-withered leaves. The results may facilitate better understanding the molecular mechanisms of solar-withering treatment in flavor formation of oolong tea.
Camellia sinensis/genetics* ; Gene Expression Profiling ; Plant Leaves ; Plant Proteins/metabolism* ; Taste ; Tea ; Transcriptome/genetics*

Resin cements have been widely employed for bonding all-ceramic restorations in clinical practice, its color stability is directly related to long-term prosthetic effect of restorations. Discoloration of resin cements can be attributed to two causes: endogenous factors are generally related to material compositions and initiation mechanism of polymerization; exogenous factors are mainly related to stimulation of local oral environment. Color stability of resin cements has close relationship with esthetic effect of all-ceramic restorations. The aim of this literature review was to make a presentation and discussion systematically about color stability of resin cements commonly used clinically, its influence factors and influence on all-ceramic restorations, so as to provide a reference for the application of all-ceramic restorations.

Objective To evaluate the efficacy of the bacterial lysate Broncho-vaxom on chronic obstructive pulmonary disease(COPD)in elderly patients.Methods A total of 150 patients with stable COPD were randomized into the Broncho-vaxom group(n=78)treated with Broncho-vaxom as add-on to conventional treatment and the control group(n=72)treated with conventional treatment.The number of acute exacerbation of COPD per patient per year,quality of life,lung function,T cell subsets were evaluated for the therapeutic effects.Results After one year of treatment,the number of acute exacerbation per patient per year was lower in Broncho-vaxom group than in control group[(1.44 ± 1.05) times/y vs.(1.82 ± 0.61) times/y,t =2.754,P =0.007].The proportions of acute exacerbationfree patients were higher in Broncho-vaxom group than in control group(20.5％ or 16/78 vs.4.2％ or 3/72,x2 =9.043,P =0.003).There were significant differences in the forced vital capacity(FVC),forced expiratory volume in one second(FEV1),and forced expiratory volume in one second/predicted value ratio(FEV1 ％)between the two groups at 5 different time points(before,at 3,6,9 and 12 months after treatment) (Broncho-vaxom group:F =90.819,50.674 and 51.233,P =0.000;control group:F =84.928,90.654 and 86.117,P =0.000).After treatment,the symptom scores were lower in Broncho-vaxom group than in control group,and the ratios of CD4/CD8 T-cell were increased and level of CD8 T-cell was decreased in Broncho-vaxom group(all P ＜ 0.05).The rate of adverse reactions had no significant difference between Broncho-vaxom group and control group(3/78 or 3.8％ vs.2/ 72 or 2.8％,x2 =0.132,P=0.717).Conclusions The oral administration of Broncho-vaxom for six months can modulate and enhance immune functions,significantly decrease acute exacerbation frequency,improve quality of life and delay the deterioration in lung function in elderly patients with stable COPD.