A novel prognostic signature based on smoking-associated genes for predicting prognosis and immune microenvironment in NSCLC smokers.

BACKGROUND: As a highly heterogeneous tumor, non-small cell lung cancer (NSCLC) is famous for its high incidence and mortality worldwide. Smoking can cause genetic changes, which leading to the occurrence and progress of NSCLC. Nevertheless, the function of smoking-related genes in NSCLC needs more research. METHODS: We downloaded transcriptome data and clinicopathological parameters from Gene Expression Omnibus (GEO) databases, and screened smoking-related genes. Lasso regression were applied to establish the 7-gene signature. The associations between the 7-gene signature and immune microenvironment analysis, survival analysis, drug sensitivity analysis and enriched molecular pathways were studied. Ultimately, cell function experiments were conducted to research the function of FCGBP in NSCLC. RESULTS: Through 7-gene signature, NSCLC samples were classified into high-risk group (HRG) and low-risk group (LRG). Significant difference in overall survival (OS) between HRG and LRG was found. Nomograms and ROC curves indicated that the 7-gene signature has a stable ability in predicting prognosis. Through the analysis of immune microenvironment, we found that LRG patients had better tumor immune activation. FCGBP showed the highest mutation frequency among the seven prognostic smoking related genes (LRRC31, HPGD, FCGBP, SPINK5, CYP24A1, S100P and FGG), and was notable down-regulated in NSCLC smokers compared with non-smoking NSCLC patients. The cell experiments confirmed that FCGBP knockdown promoting proliferation, migration, and invasion in NSCLC cells. CONCLUSION: This smoking-related prognostic signature represents a promising tool for assessing prognosis and tumor microenvironment in smokers with NSCLC. The role of FCGBP in NSCLC was found by cell experiments, which can be served as diagnostic biomarker and immunotherapy target for NSCLC.

Co-transcriptional R-loops-mediated epigenetic regulation drives growth retardation and docetaxel chemosensitivity enhancement in advanced prostate cancer.

R-loops are prevalent three-stranded nucleic acid structures, comprising a DNA-RNA hybrid and a displaced single-stranded DNA, that frequently form during transcription and may be attributed to genomic stability and gene expression regulation. It was recently discovered that RNA modification contributes to maintain the stability of R-loops such as N6-methyladenosine (m6A). Yet, m6A-modified R-loops in regulating gene transcription remains poorly understood. Here, we demonstrated that insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) recognize R-loops in an m6A-dependent way. Consequently, IGF2BPs overexpression leads to increased overall R-loop levels, cell migration inhibition, and cell growth retardation in prostate cancer (PCa) via precluding the binding of DNA methyltransferase 1(DNMT1) to semaphorin 3 F (SEMA3F) promoters. Moreover, the K homology (KH) domains of IGF2BPs are required for their recognition of m6A-containing R-loops and are required for tumor suppressor functions. Overexpression of SEMA3F markedly enhanced docetaxel chemosensitivity in prostate cancer via regulating Hippo pathway. Our findings point to a distinct R-loop resolution pathway mediated by IGF2BPs, emphasizing the functional importance of IGF2BPs as epigenetic R-loop readers in transcriptional genetic regulation and cancer biology.The manuscript summarizes the new role of N6-methyladenosine in epigenetic regulation, we introduce the distinct R-loop resolution mediated by IGF2BP proteins in an m6A-dependent way, which probably lead to the growth retardation and docetaxel chemotherapy resistance in prostate cancer. Moreover, our findings first emphasized the functional importance of IGF2BPs as epigenetic R-loop readers in transcriptional genetic regulation and cancer biology. In addition, our research provides a novel RBM15/IGF2BPs/DNMT1 trans-omics regulation m6A axis, indicating the new crosstalk between RNA m6A methylation and DNA methylation in prostate cancer.

Cancer on motors: How kinesins drive prostate cancer progression?

Prostate cancer causes numerous male deaths annually. Although great progress has been made in the diagnosis and treatment of prostate cancer during the past several decades, much about this disease remains unknown, especially its pathobiology. The kinesin superfamily is a pivotal group of motor proteins, that contains a microtubule-based motor domain and features an adenosine triphosphatase activity and motility characteristics. Large-scale sequencing analyses based on clinical samples and animal models have shown that several members of the kinesin family are dysregulated in prostate cancer. Abnormal expression of kinesins could be linked to uncontrolled cell growth, inhibited apoptosis and increased metastasis ability. Additionally, kinesins may be implicated in chemotherapy resistance and escape immunologic cytotoxicity, which creates a barrier to cancer treatment. Here we cover the recent advances in understanding how kinesins may drive prostate cancer progression and how targeting their function may be a therapeutic strategy. A better understanding of kinesins in prostate cancer tumorigenesis may be pivotal for improving disease outcomes in prostate cancer patients.

Perioperative Adjunctive Esketamine for Postpartum Depression Among Women Undergoing Elective Cesarean Delivery: A Randomized Clinical Trial.

Importance: Postpartum depression (PPD) is one of the most common mental health conditions during the perinatal and postpartum periods, which can have adverse effects on both mother and infant. Objective: To investigate the efficacy of perioperative adjunctive esketamine administration after cesarean deliveries in the prevention of PPD. Design, Setting, and Participants: A single-center, double-blind, placebo-controlled, randomized clinical trial was conducted from January 1, 2022, to January 1, 2023, at Fujian Provincial Hospital among 298 women aged 18 to 40 years, with an American Society of Anesthesiologists grade I to III classification and singleton full-term pregnancies who were scheduled for elective cesarean deliveries. Primary analyses were performed on a modified intention-to-treat basis. Interventions: Patients were randomly assigned to the esketamine (n = 148) and control (n = 150) groups. Those in the esketamine group received a single intravenous injection of 0.25 mg/kg of esketamine immediately after fetal delivery, followed by 50 mg of esketamine as an adjuvant in patient-controlled intravenous analgesia for 48 hours after surgery. Saline was given to the control group of patients. Main Outcomes and Measures: The primary outcome was assessments of PPD symptoms by using the Edinburgh Postnatal Depression Scale (EPDS) at postpartum day 7. Positive screening for PPD was defined as a score of 10 or more points on the EPDS. In addition, the EPDS was analyzed as a continuous variable to evaluate depressive symptoms. Secondary outcomes included the Numeric Rating Scale (NRS) of postoperative pain, along with safety evaluations including adverse events and clinical assessments at postpartum days 14, 28, and 42. Results: A total of 298 pregnant women were included, with 150 in the control group (median age, 31.0 years [IQR, 29.0-34.0 years]) and 148 in the esketamine group (median age, 31.0 years [IQR, 28.0-34.0 years]). The prevalence of depression symptoms was significantly lower among patients given esketamine compared with controls (23.0% [34 of 148] vs 35.3% [53 of 150]; odds ratio, 0.55; 95% CI, 0.33-0.91; P = .02) on postpartum day 7. In addition, the esketamine group also showed a significantly lower change in EPDS scores (difference of least-squares means [SE], -1.17 [0.44]; 95% CI, -2.04 to -0.31; effect size, 0.74; P = .008). However, there were no differences between the groups in the incidence of positive screening results for PPD or in changes from the baseline EPDS scores at postpartum days 14, 28, and 42. There were no differences in NRS scores at rest and on movement except on movement at 72 hours postoperatively, when scores were significantly lower in the esketamine group (median, 3.0 [IQR, 2.0-3.0] vs 3.0 [IQR, 3.0-3.5]; median difference, 0 [95% CI, 0-0]; P = .03). Conclusions and Relevance: These results suggest that intravenous administration of esketamine during the perioperative period of elective cesarean delivery can improve depression symptoms during the early postpartum period. However, this antidepression effect may not be universally applicable to patients with low EPDS scores. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR2100054199.

PPT1 Promotes Growth and Inhibits Ferroptosis of Oral Squamous Cell Carcinoma Cells.

BACKGROUND: Oral Squamous Cell Carcinoma (OSCC) is one of the most prevalent cancers with poor prognosis in the head and neck. Elucidating molecular mechanisms underlying OSCC occurrence and development is important for the therapy. Dysregulated palmitoylation-related enzymes have been reported in several cancers but OSCC. OBJECTIVE: To explore the role of palmitoyl protein thioesterase 1 (PPT1) in OSCC. METHODS: Differentially Expressed Genes (DEGs) and related protein-protein interaction networks between normal oral epithelial and OSCC tissues were screened and constructed via different online databases. Tumor samples from 70 OSCC patients were evaluated for the relationship between PPT1 expression level and patients'clinic characteristics. The role of PPT1 in OSCC proliferation and metastasis was studied by functional experiments, including MTT, colony formation, EdU incorporation and transwell assays. Lentivirus-based constructs were used to manipulate the gene expression. FerroOrange probe and malondialdehyde assay were used to determine ferroptosis. Growth of OSCC cells in vivo was investigated by a xenograft mouse model. RESULTS: A total of 555 DEGs were obtained, and topological analysis revealed that the PPT1 and GPX4 might play critical roles in OSCC. Increased PPT1 expression was found to be correlated with poor prognosis of OSCC patients. PPT1 effectively promoted the proliferation, migration and invasion while inhibiting the ferroptosis of OSCC cells. PPT1 affected the expression of glutathione peroxidase 4 (GPX4). CONCLUSION: PPT1 promoted growth and inhibited ferroptosis of OSCC cells. PPT1 might be a potential target for OSCC therapy.

A cuproptosis score model and prognostic score model can evaluate clinical characteristics and immune microenvironment in NSCLC.

BACKGROUND: Cuproptosis-related genes (CRGs) are associated with lung adenocarcinoma. However, the links between CRGs and non-small-cell lung cancer (NSCLC) are not clear. In this study, we aimed to develop two cuproptosis models and investigate their correlation with NSCLC in terms of clinical features and tumor microenvironment. METHODS: CRG expression profiles and clinical data from NSCLC and normal tissues was obtained from GEO (GSE42127) and TCGA datasets. Molecular clusters were classified into three patterns based on CRGs and cuproptosis cluster-related specific differentially expressed genes (CRDEGs). Then, two clinical models were established. First, a prognostic score model based on CRDEGs was established using univariate/multivariate Cox analysis. Then, through principal component analysis, a cuproptosis score model was established based on prognosis-related genes acquired via univariate analysis of CRDEGs. NSCLC patients were divided into high/low risk groups. RESULTS: Eighteen CRGs were acquired, all upregulated in tumor tissues, 15 of which significantly (P < 0.05). Among the three CRG clusters, cluster B had the best prognosis. In the CRDEG clusters, cluster C had the best survival. In the prognostic score model, the high-risk group had worse prognosis, higher tumor mutation load, and lower immune infiltration while in the cuproptosis score model, a high score represented better survival, lower tumor mutation load, and high-level immune infiltration. CONCLUSIONS: The cuproptosis score model and prognostic score model may be associated with NSCLC prognosis and immune microenvironment. These novel findings on the progression and immune landscape of NSCLC may facilitate the provision of more personalized immunotherapy interventions for NSCLC patients.

N6-methyladenosine-modified CircPSMA7 enhances bladder cancer malignancy through the miR-128-3p/MAPK1 axis.

Several studies have indicated that circular RNAs (circRNAs) play vital roles in the progression of various diseases, including bladder cancer (BCa). However, the underlying mechanisms by which circRNAs drive BCa malignancy remain unclear. In this study, we identified a novel circRNA, circPSMA7 (circbaseID:has_circ_0003456), showing increased expression in BCa cell lines and tissues, by integrating the reported information with circRNA-seq and qRT-PCR. We revealed that circPSMA7 is associated with a higher tumor grade and stage in BCa. M6A modification was identified in circPSMA7, and IGF2BP3 recognized this modification and stabilized circPSMA7, subsequently increasing the circPSMA7 expression. In vitro and in vivo experiments showed that circPSMA7 promoted BCa proliferation and metastasis by regulating the cell cycle and EMT processes. CircPSMA7 acted as a sponge for miR-128-3p, which showed antitumor effects in BCa cell lines, increasing the expression of MAPK1. The tumor proliferation and metastasis suppression induced by silencing circPSMA7 could be partly reversed by miR-128-3p inhibition. Thus, the METTL3/IGF2BP3/circPSMA7/miR-128-3p/MAPK1 axis plays a critical role in BCa progression. Furthermore, circPSMA7 may be a potential diagnostic biomarker and novel therapeutic target for patients with BCa.

An S=1 Iron(IV) Intermediate Revealed in a Non-Heme Iron Enzyme-Catalyzed Oxidative C-S Bond Formation.

Ergothioneine (ESH) and ovothiol A (OSHA) are two natural thiol-histidine derivatives. ESH has been implicated as a longevity vitamin and OSHA inhibits the proliferation of hepatocarcinoma. The key biosynthetic step of ESH and OSHA in the aerobic pathways is the O2 -dependent C-S bond formation catalyzed by non-heme iron enzymes (e.g., OvoA in ovothiol biosynthesis), but due to the lack of identification of key reactive intermediate the mechanism of this novel reaction is unresolved. In this study, we report the identification and characterization of a kinetically competent S=1 iron(IV) intermediate supported by a four-histidine ligand environment (three from the protein residues and one from the substrate) in enabling C-S bond formation in OvoA from Methyloversatilis thermotoleran, which represents the first experimentally observed intermediate spin iron(IV) species in non-heme iron enzymes. Results reported in this study thus set the stage to further dissect the mechanism of enzymatic oxidative C-S bond formation in the OSHA biosynthesis pathway. They also afford new opportunities to study the structure-function relationship of high-valent iron intermediates supported by a histidine rich ligand environment.

ADCY9 functions as a novel cancer suppressor gene in lung adenocarcinoma.

Background: The process of lucubrating into lung adenocarcinoma (LUAD) is of profound clinical and practical significance in improving the prognosis of LUAD patients. Multiple biomarkers are reportedly involved in the proliferation or metastasis of adenocarcinoma. However, whether the ADCY9 gene influences the development of LUAD remains unknown. Therefore, we aimed to elucidate the relationship between the expression of ADCY9 and the proliferation and migration of LUAD. Methods: The ADCY9 gene was filtered via a survival analysis of LUAD acquired from the Gene Expression Omnibus (GEO). Then, we conducted a validation analysis and ADCY9-microRNA, microRNA-lncRNA, and ADCY9-lncRNA targeting relationship analysis through the data obtained from The Cancer Genome Atlas (TCGA) dataset. The survival curve, correlation, and prognostic analysis were implemented through bioinformatics methods. Both protein and mRNA expression levels of LUAD cell lines and LUAD patient samples (80 pairs) were detected using western blot assays and quantitative real-time polymerase chain reaction (qRT-PCR). An immunohistochemistry assay was performed to display the correlation between the expression level of the ADCY9 gene and prognosis in LUAD patients (2012-2013; n=115). Overexpression of cell lines SPCA1 and A549 were used for a series of cell function assays. Results: Compared with the expression level in adjacent normal tissues, ADCY9 expression was downregulated in LUAD tissues. Based on the result of the survival curve analysis, high expression of ADCY9 may lead to a better prognosis and may be seen as an independent predictor for LUAD patients. High expression of ADCY9-related microRNA hsa-miR-7-5p may lead to a worse prognosis, and high expression of hsa-miR-7-5p-related lncRNAs may lead to the opposite effects. Overexpression of ADCY9 restrained the proliferation, invasion, and migration abilities of SPCA1, A549 cells. Conclusions: Results indicate that the ADCY9 gene acts as a tumor suppressor to restrain the proliferation, migration, and invasion in LUAD and can lead to a better survival or prognosis in LUAD patients.

Novel immunogenic cell death-related risk signature to predict prognosis and immune microenvironment in lung adenocarcinoma.

PURPOSE: Immunogenic cell death (ICD) is a type of regulated cell death (RCD) which was discovered to activate adaptive immunity. To date, the effect of ICD on lung adenocarcinoma (LUAD) remains unclear. In this research, we will study the role of ICD-related genes (ICDG) in LUAD. METHODS: RNA sequencing and clinical data were gathered from TCGA-LUAD cohorts and GEO database. Using unsupervised cluster analysis, three clusters were identified with distinctive immune characteristics and significant overall survival based on 18 ICDG. Using LASSO Cox regression, three genes were identified and used to construct the prognosis signature. The association between the 3-ICDG risk signature and immune microenvironment analysis, somatic mutation, and enriched molecular pathways was investigated. RESULTS: Consensus clustering separated the LUAD samples into three clusters (ICDcluster A, B and C), and ICDcluster B had the best prognosis. Different TME cell infiltration characteristics and biological behavior were found in three ICD clusters. Prognostic risk model was contrasted based on the 3 best prognostic ICD-related genes. Subsequently, vitro experiments verified the above analysis results. The high-risk group showed a poor prognosis and enrichment of cancer promoting signal pathway. Multivariate analysis indicated that this 3-ICDG prognostic model might be an accurate prediction parameter for LUAD. Moreover, conducting immune related analysis, we found that the 3-ICDG risk signature was characterized by an immune-active subtype on account of the high infiltration of immune-active cells. CONCLUSION: This study expands our cognition of ICD in LUAD microenvironment, excavated prognostic biomarkers, and provided potential value for guiding immunotherapy and chemotherapy.

Characteristic of Molecular Subtypes in Lung Squamous Cell Carcinoma Based on Autophagy-Related Genes and Tumor Microenvironment Infiltration.

Background: Recently, a large number of studies have sought personalized treatment for lung squamous cell carcinoma (LUSC) by dividing patients into different molecular subtypes. Autophagy plays an important role in maintaining the tumor microenvironment and immune-related biological processes. However, the molecular subtypes mediated by autophagy in LUSC are not clear. Methods: Based on 490 LUSC samples, we systematically analyzed the molecular subtype modification patterns mediated by autophagy-related genes. The ssGSEA and CIBERSORT algorithm were utilized to quantify the relative abundance of TME cell infiltration. Principal component analysis was used to construct autophagy prognostic score (APS) model. Results: We identified three autophagy subtypes in LUSC, and their clinical outcomes and TME cell infiltration had significant heterogeneity. Cluster A was rich in immune cell infiltration. The enrichment of EMT stromal pathways and immune checkpoint molecules were significantly enhanced, which may lead to its immunosuppression. Cluster B was characterized by relative immunosuppression and relative stromal activation. Cluster C was activated in biological processes related to repair. Patients with high APS were significantly positively correlated with TME stromal activity and poor survival. Meanwhile, high APS showed an advantage in response to anti-PD1 and anti-CTLA4 immunotherapy. Conclusion: This study explored the autophagy molecular subtypes in LUSC. We also discovered the heterogeneity of TME cell infiltration driven by autophagy-related genes. The established APS model is of great significance for evaluating the prognosis of LUSC patients, the infiltration of TME cells, and the effect of immunotherapy.

Deciphering the Reaction Pathway of Mononuclear Iron Enzyme-Catalyzed N≡C Triple Bond Formation in Isocyanide Lipopeptide and Polyketide Biosynthesis.

Despite the diversity of reactions catalyzed by 2-oxoglutarate-dependent nonheme iron (Fe/2OG) enzymes identified in recent years, only a limited number of these enzymes have been investigated in mechanistic detail. In particular, several Fe/2OG-dependent enzymes capable of catalyzing isocyanide formation have been reported. While the glycine moiety has been identified as a biosynthon for the isocyanide group, how the actual conversion is effected remains obscure. To elucidate the catalytic mechanism, we characterized two previously unidentified (AecA and AmcA) along with two known (ScoE and SfaA) Fe/2OG-dependent enzymes that catalyze N≡C triple bond installation using synthesized substrate analogues and potential intermediates. Our results indicate that isocyanide formation likely entails a two-step sequence involving an imine intermediate that undergoes decarboxylation-assisted desaturation to yield the isocyanide product. Results obtained from the in vitro experiments are further supported by mutagenesis, the product-bound enzyme structure, and in silico analysis.

OvoAMtht from Methyloversatilis thermotolerans ovothiol biosynthesis is a bifunction enzyme: thiol oxygenase and sulfoxide synthase activities.

Mononuclear non-heme iron enzymes are a large class of enzymes catalyzing a wide-range of reactions. In this work, we report that a non-heme iron enzyme in Methyloversatilis thermotolerans, OvoAMtht, has two different activities, as a thiol oxygenase and a sulfoxide synthase. When cysteine is presented as the only substrate, OvoAMtht is a thiol oxygenase. In the presence of both histidine and cysteine as substrates, OvoAMtht catalyzes the oxidative coupling between histidine and cysteine (a sulfoxide synthase). Additionally, we demonstrate that both substrates and the active site iron's secondary coordination shell residues exert exquisite control over the dual activities of OvoAMtht (sulfoxide synthase vs. thiol oxygenase activities). OvoAMtht is an excellent system for future detailed mechanistic investigation on how metal ligands and secondary coordination shell residues fine-tune the iron-center electronic properties to achieve different reactivities.

STEAP4 promoter methylation correlates with tumorigenesis of hepatocellular carcinoma.

BACKGROUND: The study was aimed to find promising targets for cancer therapy involved in the tumorigenesis of hepatocellular carcinoma (HCC). METHODS: Identification of STEAP4 in HCC between GSE54503 and TCGA datasets by performing RNA-seq. The STEAP4 mRNA expression level was determined by qRT-PCR. DNA methylation was measured by MSP and BSP. Besides, the effect of STEAP4 tumorigenesis was determined by in vivo experiments. The function of STEAP4 on methylation was further assessed by 5-Aza­dC, a demethylating agent. RESULTS: Reduced STEAP4 expression was found in HCC tissues. Promoter region methylation correlated with the downregulated expression of STEAP4. STEAP4 inhibited the proliferation and metastasis of HCC cells. Re-expression of STEAP4 was induced 5-Aza­dC. STEAP4 mediated the biological effects of HCC cells through PI3K/AKT/mTOR pathway inhibition. CONCLUSIONS: Our findings indicate that STEAP4 functions as a suppressor gene in HCC, and hypermethylation is a driving factor in cancer progression.

Relationship between circadian genes and memory impairment caused by sleep deprivation.

Background: Sleep deprivation (SD)-induced cognitive impairment is highly prevalent worldwide and has attracted widespread attention. The temporal and spatial oscillations of circadian genes are severely disturbed after SD, leading to a progressive loss of their physiological rhythms, which in turn affects memory function. However, there is a lack of research on the role of circadian genes and memory function after SD. Therefore, the present study aims to investigate the relationship between circadian genes and memory function and provide potential therapeutic insights into the mechanism of SD-induced memory impairment. Methods: Gene expression profiles of GSE33302 and GSE9442 from the Gene Expression Omnibus (GEO) were applied to identify differentially expressed genes (DEGs). Subsequently, both datasets were subjected to Gene Set Enrichment Analysis (GSEA) to determine the overall gene changes in the hippocampus and brain after SD. A Gene Oncology (GO) analysis and Protein-Protein Interaction (PPI) analysis were employed to explore the genes related to circadian rhythm, with their relationship and importance determined through a correlation analysis and a receiver operating characteristic curve (ROC), respectively. The water maze experiments detected behavioral changes related to memory function in SD rats. The expression of circadian genes in several critical organs such as the brain, heart, liver, and lungs and their correlation with memory function was investigated using several microarrays. Finally, changes in the hippocampal immune environment after SD were analyzed using the CIBERSORT in R software. Results: The quality of the two datasets was very good. After SD, changes were seen primarily in genes related to memory impairment and immune function. Genes related to circadian rhythm were highly correlated with engagement in muscle structure development and circadian rhythm. Seven circadian genes showed their potential therapeutic value in SD. Water maze experiments confirmed that SD exacerbates memory impairment-related behaviors, including prolonged escape latencies and reduced numbers of rats crossing the platform. The expression of circadian genes was verified, while some genes were also significant in the heart, liver, and lungs. All seven circadian genes were also associated with memory markers in SD. The contents of four immune cells in the hippocampal immune environment changed after SD. Seven circadian genes were related to multiple immune cells. Conclusions: In the present study, we found that SD leads to memory impairment accompanied by changes in circadian rhythm-related genes. Seven circadian genes play crucial roles in memory impairment after SD. Naïve B cells and follicular helper T cells are closely related to SD. These findings provide new insights into the treatment of memory impairment caused by SD.

Integrative Analysis of m6A RNA Methylation Regulators and the Tumor Immune Microenvironment in Non-Small-Cell Lung Cancer.

BACKGROUND: Non-small-cell lung cancer (NSCLC) is a major component of lung cancer and is significantly correlated with poor prognosis. N6-methyladenosine (m6A) RNA methylation is closely related to the occurrence, progression, and prognosis of cancer. The potential biological functions and mechanisms of m6A RNA methylation in the immune microenvironment are still unclear. METHODS: We assessed m6A RNA methylation modification patterns in 1326 NSCLC patient samples based on 20 m6A regulators, linking these clusters to the tumor microenvironment and immune cell infiltration. The m6Ascore was created to quantify the m6A modification patterns of individual tumors. We then assessed the value of NSCLC patients in terms of clinical prognosis and immunotherapy response. RESULTS: According to different mRNA expression levels, two different m6A clusters were identified. m6A aggregation was significantly associated with clinical prognostic characteristics, the tumor microenvironment, and immune-related biological processes. Fifteen differential genes were screened based on these two m6A clusters, and to further investigate the mechanisms of action of these differential genes, they were subjected to unsupervised clustering analysis, which classified them into four different genomic isoforms. Prognostic analysis indicated that the survival advantage of the m6A gene cluster A modification mode was significantly prominent. We continued to construct the m6Ascore, which was used as a scoring tool to evaluate tumor typing, immunity, and prognosis. Patients with a low m6Ascore showed a significant survival advantage, and the group with a low m6Ascore had a better prognosis predicted by immunotherapy. The anti-PD-1/L1 immunotherapy cohort showed that a lower m6Ascore was associated with higher efficacy of immunotherapy. CONCLUSIONS: The results suggest that m6A RNA methylation regulators make an important difference in the tumor immune microenvironment of patients with NSCLC. m6A gene characterization and the construction of the m6Ascore provide us with a richer understanding of m6A RNA methylation modification patterns in NSCLC patients and help to predict clinical prognosis and immunotherapeutic response.

Relieving immunosuppression by Endo@PLT targeting anti-angiogenesis to improve the efficacy of immunotherapies.

Low levels of immune infiltrates in the tumor milieu hinder the effectiveness of immunotherapy against immune-cold tumors. In the current work, a tumor-targeting drug delivery system composed of Endo-loaded platelets (Endo@PLT) was developed to relieve immunosuppression by achieving tumor vascular normalization. Endo@PLT reprogrammed the immunostimulatory phenotype, achieving excellent PD-1 immunotherapy in vivo.

circRNAome profiling reveals circFgfr2 regulates myogenesis and muscle regeneration via a feedback loop.

BACKGROUND: Circular RNAs (circRNAs) represent a novel class of non-coding RNAs formed by a covalently closed loop and play crucial roles in many biological processes. Several circRNAs associated with myogenesis have been reported. However, the dynamic expression, function, and mechanism of circRNAs during myogenesis and skeletal muscle development are largely unknown. METHODS: Strand-specific RNA-sequencing (RNA-seq) and microarray datasets were used to profile the dynamic circRNAome landscape during skeletal muscle development and myogenic differentiation. Bioinformatics analyses were used to characterize the circRNAome and identify candidate circRNAs associated with myogenesis. Bulk and single-cell RNA-seq were performed to identify the downstream genes and pathways of circFgfr2. The primary myoblast cells, C2C12 cells, and animal model were used to assess the function and mechanism of circFgfr2 in myogenesis and muscle regeneration in vitro or in vivo by RT-qPCR, western blotting, dual-luciferase activity assay, RNA immunoprecipitation, RNA fluorescence in situ hybridization, and chromatin immunoprecipitation. RESULTS: We profiled the dynamic circRNAome in pig skeletal muscle across 27 developmental stages and detected 52 918 high-confidence circRNAs. A total of 2916 of these circRNAs are conserved across human, mouse, and pig, including four circRNAs (circFgfr2, circQrich1, circMettl9, and circCamta1) that were differentially expressed (|log2 fold change| > 1 and adjusted P value < 0.05) in various myogenesis systems. We further focused on a conserved circRNA produced from the fibroblast growth factor receptor 2 (Fgfr2) gene, termed circFgfr2, which was found to inhibit myoblast proliferation and promote differentiation and skeletal muscle regeneration. Mechanistically, circFgfr2 acted as a sponge for miR-133 to regulate the mitogen-activated protein kinase kinase kinase 20 (Map3k20) gene and JNK/MAPK pathway. Importantly, transcription factor Kruppel like factor 4 (Klf4), the downstream target of the JNK/MAPK pathway, directly bound to the promoter of circFgfr2 and affected its expression via an miR-133/Map3k20/JNK/Klf4 auto-regulatory feedback loop. RNA binding protein G3BP stress granule assembly factor 1 (G3bp1) inhibited the biogenesis of circFgfr2. CONCLUSIONS: The present study provides a comprehensive circRNA resource for skeletal muscle study. The functional and mechanistic analysis of circFgfr2 uncovered a circRNA-mediated auto-regulatory feedback loop regulating myogenesis and muscle regeneration, which provides new insight to further understand the regulatory mechanism of circRNAs.

Landscape of tissue-specific RNA Editome provides insight into co-regulated and altered gene expression in pigs (Sus-scrofa).

RNA editing generates genetic diversity in mammals by altering amino acid sequences, miRNA targeting site sequences, influencing the stability of targeted RNAs, and causing changes in gene expression. However, the extent to which RNA editing affect gene expression via modifying miRNA binding site remains unexplored. Here, we first profiled the dynamic A-to-I RNA editome across tissues of Duroc and Luchuan pigs. The RNA editing events at the miRNA binding sites were generated. The biological function of the differentially edited gene in skeletal muscle was further characterized in pig muscle-derived satellite cells. RNA editome analysis revealed a total of 171,909 A-to-I RNA editing sites (RESs), and examination of its features showed that these A-to-I editing sites were mainly located in SINE retrotransposons PRE-1/Pre0_SS element. Analysis of differentially edited sites (DESs) revealed a total of 4,552 DESs across tissues between Duroc and Luchuan pigs, and functional category enrichment analysis of differentially edited gene (DEG) sets highlighted a significant association and enrichment of tissue-developmental pathways including TGF-beta, PI3K-Akt, AMPK, and Wnt signaling pathways. Moreover, we found that RNA editing events at the miRNA binding sites in the 3'-UTR of HSPA12B mRNA could prevent the miRNA-mediated mRNA downregulation of HSPA12B in the muscle-derived satellite (MDS) cell, consistent with the results obtained from the Luchuan skeletal muscle. This study represents the most systematic attempt to characterize the significance of RNA editing in regulating gene expression, particularly in skeletal muscle, constituting a new layer of regulation to understand the genetic mechanisms behind phenotype variance in animals.Abbreviations: A-to-I: Adenosine-to-inosine; ADAR: Adenosine deaminase acting on RNA; RES: RNA editing site; DEG: Differentially edited gene; DES: Differentially edited site; FDR: False discovery rate; GO: Gene Ontology; KEGG: Kyoto Encyclopaedia of Genes and Genomes; MDS cell: musclederived satellite cell; RPKM: Reads per kilobase of exon model in a gene per million mapped reads; UTR: Untranslated coding regions.

Sp1-Mediated circRNA circHipk2 Regulates Myogenesis by Targeting Ribosomal Protein Rpl7.

Circular RNAs (circRNAs) represent a class of covalently closed single-stranded RNA molecules that are emerging as essential regulators of various biological processes. The circRNA circHipk2 originates from exon 2 of the Hipk2 gene in mice and was reported to be involved in acute promyelocytic leukemia and myocardial injury. However, the functions and mechanisms of circHipk2 in myogenesis are largely unknown. Here, to deepen our knowledge about the role of circHipk2, we studied the expression and function of circHipk2 during skeletal myogenesis. We found that circHipk2 was mostly distributed in the cytoplasm, and dynamically and differentially expressed in various myogenesis systems in vitro and in vivo. Functionally, overexpression of circHipk2 inhibited myoblast proliferation and promoted myotube formation in C2C12 cells, whereas the opposite effects were observed after circHipk2 knockdown. Mechanistically, circHipk2 could directly bind to ribosomal protein Rpl7, an essential 60S preribosomal assembly factor, to inhibit ribosome translation. In addition, we verified that transcription factor Sp1 directly bound to the promoter of circHipk2 and affected the expression of Hipk2 and circHipk2 in C2C12 myoblasts. Collectively, these findings identify circHipk2 as a candidate circRNA regulating ribosome biogenesis and myogenesis proliferation and differentiation.