N⁶-methyladenosine (m⁶A) modification plays a critical role in cell cycle regulation, while the mechanism of m⁶A in regulating mitosis remains underexplored. Here, we found that the total m⁶A modification level in cells increased during mitosis by the liquid chromatography-mass spectrometry/mass spectrometry and m⁶A dot blot assays. Silencing methyltransferase-like 3 (METTL3) or METTL14 results in delayed mitosis, abnormal spindle assembly, and chromosome segregation defects by the immunofluorescence. By analyzing transcriptome-wide m⁶A targets in HeLa cells, we identified polo-like kinase 1 (PLK1) as a key gene modified by m⁶A in regulating mitosis. Specifically, through immunoblotting and RNA pulldown, m⁶A modification inhibits PLK1 translation via YTH N⁶-methyladenosine RNA binding protein 1, thus mediating cell cycle homeostasis. Demethylation of PLK1 mRNA leads to significant mitotic abnormalities. These findings highlight the critical role of m⁶A in regulating mitosis and the potential of m⁶A as a therapeutic target in proliferative diseases such as cancer.
Humans ; Polo-Like Kinase 1 ; Cell Cycle Proteins/metabolism* ; Proto-Oncogene Proteins/metabolism* ; Protein Serine-Threonine Kinases/metabolism* ; Mitosis/physiology* ; HeLa Cells ; Adenosine/genetics* ; Methyltransferases/metabolism* ; RNA, Messenger/metabolism* ; RNA-Binding Proteins/metabolism*

OBJECTIVE: To evaluate the protective effects of resveratrol against acute lung injury (ALI) and investigate the potential mechanisms underlying the reactive oxygen species (ROS)-triggered thioredoxin-interacting protein (TXNIP)/NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) pathway. METHODS: C57BL/6 mice and J774A.1 cells were selected as the research subjects. Thirty Mice were randomly divided into 5 groups of 6 in each group: control with 0.9% saline, 5 mg/kg lipopolysaccharide (LPS) 24 h, 25 mg/kg resveratrol + 5 mg/kg LPS, 100 mg/kg resveratrol + 5 mg/kg LPS, and 4 mg/kg NLRP3 inhibitor CY-09 + 5 mg/kg LPS. For cell stimulation, cells were pretreated with 5 and 20 µmol/L resveratrol for 2 h, and stimulated with or without 1 µg/mL LPS and 3 mmol/L ATP for 2 h. The antioxidant N-acetyl-L-cysteine (NAC, 2 µmol/L) was used as the positive control group. Hematoxylin and eosin staining was used to evaluate the degree of lung LPS-induced tissue damage, and enzyme-linked immunosorbent assay was used to evaluate the contents of interleukin-1 β (IL-1 β) and IL-18 in the serum and cell supernatant. ROS and malondialdehyde (MDA) levels in the lung tissue were detected using the corresponding kits. Western blotting was used to detect the expressions of TXNIP, high-mobility group box 1 (HMGB1), NLRP3, as well as cysteine-aspartic acid protease 1 (caspase-1) and gasdermin D (GSDMD) along with their cleaved forms in lung tissue. Additionally, reverse transcription quantitative polymerase chain reaction was performed to analyze the expression of related inflammatory cytokines. ROS content was detected using flow cytometry and confocal laser microscopy. Mitochondrial morphological changes were observed using transmission electron microscopy, and HMGB1 expression was detected using immunofluorescence. RESULTS: Resveratrol significantly alleviated LPS-induced lung damage with reduced inflammation, interstitial edema, and leukocyte infiltration (P<0.01). It also decreased serum levels of IL-1 β and IL-18 (P<0.05), while downregulating the expressions of NLRP3, IL-6, and other inflammatory markers at both the protein and mRNA levels (P<0.05). Notably, the higher dose (100 mg/kg) demonstrated a better effect than the lower dose (25 mg/kg). In macrophages, resveratrol reduced IL-1 β and IL-18 following LPS and ATP stimulation, suppressed HMGB1 translocation, and inhibited formation and activation of the NLRP3 inflammasome (P<0.05 or P<0.01). These anti-inflammatory effects were mediated through the suppression ROS accumulation (P<0.01) and mitochondrial dysfunction. Transmission electron microscopy revealed that resveratrol preserved mitochondrial structure, preventing the mitochondrial damage seen in LPS-treated groups (P<0.01). The expressions of cleaved caspase-1, cleaved GSDMD, and cytoplasmic HMGB1 were all reduced following resveratrol treatment (P<0.01). Moreover, resveratrol inhibited dissociation of TXNIP from thioredoxin, blocking subsequent activation of NLRP3 and downstream inflammatory cytokines (P<0.01). Similarly, the higher concentration of resveratrol (20 µ mol/L) exhibited superior efficacy in vitro. CONCLUSION Resveratrol can reduce the inflammatory response following ALI and inhibit the activation of NLRP3 inflammasome and the level of HMGB1 in the cytoplasm by inhibiting ROS overproduction.
Acute Lung Injury/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Animals ; Resveratrol/pharmacology* ; Reactive Oxygen Species/metabolism* ; Inflammation/complications* ; Mice, Inbred C57BL ; Carrier Proteins/metabolism* ; Signal Transduction/drug effects* ; Lipopolysaccharides ; Thioredoxins/metabolism* ; Mice ; Lung/drug effects* ; Male ; Cell Line ; Interleukin-1beta/metabolism* ; Cell Cycle Proteins ; Stilbenes/therapeutic use*

OBJECTIVES: Metastasis is the primary cause of death in osteosarcoma, and current clinical treatments remain limited. BRD4, a key epigenetic regulator, has shown therapeutic promise in various cancers through its inhibition. However, the mechanistic role of BRD4 in osteosarcoma remains poorly understood. This study aims to elucidate the molecular mechanisms by which BRD4 regulate osteosarcoma progression and to explore novel therapeutic strategies. METHODS: Immunofluorescence was used to assess BRD4 expression levels in a tissue microarray containing 80 osteosarcoma samples from different patients. The Gene Expression Omnibus (GEO) dataset (GSE42352, containing survival data from 88 osteosarcoma patients) was downloaded to perform Kaplan-Meier survival analysis based on BRD4 gene expression levels. In vivo, an orthotopic intramedullary osteosarcoma model was established using HOS cells in C57 mice, followed by treatment with varying doses of the BRD4 inhibitor (+)-JQ1. Micro-CT, 3D reconstruction of bone tissue, and HE staining were employed to evaluate pathological changes in bone and intestinal lymph nodes. In vitro, cell viability was measured using the methyl thiazolyl tetrazolium (MTT) assay, while colony formation and Transwell assays assessed proliferative and invasive capacities. Chromatin-bound BRD4 was analyzed via co-immunoprecipitation combined with mass spectrometry (Co-IP/MS), and O-GlcNAc glycosylation sites and glycan chains of BRD4 were identified using Co-IP with Nano-LC MS/MS. Real-time PCR and Western blotting were used to analyze the relative mRNA and protein expression levels of target genes, respectively. RESULTS: BRD4 was positively expressed in 61.25% (49/80) of osteosarcoma tissues. Patients with high BRD4 expression exhibited significantly shorter survival times (P<0.05). In the orthotopic mouse model, intervention with (+)-JQ1, a potent and commonly used BETi, significantly inhibited tumor growth in vivo and reduced bone destruction (P<0.05). (+)-JQ1 treatment significantly suppressed the proliferation (P<0.001), invasion (P<0.001), and migration (P<0.05) of HOS cells. In osteosarcoma cells, BRD4 exhibited O-GlcNAc modifications at both N- and C- C-termini, particularly at Thr73, which is essential for protein stability. This modification also contributed to the activation of the EGFR tyrosine kinase inhibitor resistance pathway (KEGG Pathway: hsa01521). (+)-JQ1 treatment displaced BRD4 from enhancers and downregulated the transcription of pathway-related genes, such as EGFR and PDGFC, thereby suppressing the malignant behavior of osteosarcoma cells. CONCLUSIONS BRD4 promotes osteosarcoma progression via O-GlcNAc modification at Thr73 and plays a crucial role in tumor growth and metastasis.
Osteosarcoma/drug therapy* ; Humans ; Transcription Factors/metabolism* ; Animals ; Cell Cycle Proteins ; Mice ; Bone Neoplasms/drug therapy* ; Azepines/pharmacology* ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Triazoles/pharmacology* ; Mice, Inbred C57BL ; Nuclear Proteins/metabolism* ; Gene Expression Regulation, Neoplastic ; Male ; Bromodomain Containing Proteins

Objective:To investigate the molecular characteristics and clinical heterogeneity of Usher syndrome（USH） -related gene variants in patients with hereditary hearing loss in southwest China, providing a basis for early diagnosis and clinical management. Methods:Thirteen patients from twelve families with hearing loss who attended the Affiliated Children's Hospital of Kunming Medical University between January 2017 and March 2021 were enrolled. All patients were identified as carrying USH-related gene variants through next-generation sequencing. Sanger sequencing was performed for all patients and their parents to validate the pathogenic variants. Comprehensive clinical evaluations, including medical history collection, otologic and ophthalmologic examinations, and vestibular function assessments, were conducted. Results:Among the 13 patients, 4 were diagnosed with USH type 1 and 2 with USH type 2. A total of 19 pathogenic or likely pathogenic variants were detected in USH-related genes, including MYO7A,CDH23,USH1C, and USH2A. The causative gene was MYO7A in 3 probands, CDH23 in 5, USH1C in 3, and USH2Ain 2. All patients exhibited an autosomal recessive inheritance pattern. Vestibular dysfunction was observed in 4 patients, and retinitis pigmentosa（RP） in 3 patients. Based on the genotype-phenotype correlation, 6 patients were initially diagnosed with USH, while 7 were classified as having non-syndromic hearing loss（NSHL）. Conclusion:This study revealed the clinical heterogeneity of USH-related gene variants in patients with hereditary deafness in southwest China. Although the clinical manifestations of USH are complex and there are overlapping characteristics between different subtypes, genetic testing provides an important basis for early diagnosis and precise clinical management. Especially for those with typical hearing loss, early genetic diagnosis can provide a window of time for early detection and intervention of retinitis pigmentosa.
Humans ; Usher Syndromes/genetics* ; Myosin VIIa ; Phenotype ; Male ; Female ; Myosins/genetics* ; Mutation ; Cadherins/genetics* ; Child ; Extracellular Matrix Proteins/genetics* ; Adolescent ; Pedigree ; High-Throughput Nucleotide Sequencing ; Cadherin Related Proteins ; Cytoskeletal Proteins ; Cell Cycle Proteins

OBJECTIVE: To summarize the clinical characteristics, diagnosis, treatment and prognosis of dyskeratosis congenita (DC) in children, and to provide clinical experience for the diagnosis and treatment of DC. METHODS: The clinical data of children with dyskeratosis congenital admitted to Children's Hospital of Soochow University from May 2016 to May 2024 were retrospectively analyzed. Whole exome sequencing (WES) was performed, the patients were followed up and the related literature was reviewed. RESULTS: A total of 4 patients were enrolled. There were 1 male and 3 females. Two patients had spontaneous TINF2 mutation, one had TERT mutation, and one had DKC1 mutation. All of them had bone marrow hypoplasia. Two patients underwent allogeneic hematopoietic stem cell transplantation, and both had good engraftment. Anti-rejection drugs were stopped, and they survived more than 5 years of follow-up. One patient was followed up in outpatient department, and another patient was scheduled to undergo hematopoietic stem cell transplantation. CONCLUSION The onset of dyskeratosis congenita in children is insidious, so genetic diagnosis is particularly important. c.853_861delGTCATGCTG (p.285-287del) was a new mutation site of TINF2, which expanded the gene mutation spectrum of DC. Hematopoietic stem cell transplantation is an effective treatment for bone marrow failure, and the treatment of other organ complications depends on further genetic exploration.
Humans ; Dyskeratosis Congenita/therapy* ; Hematopoietic Stem Cell Transplantation ; Male ; Mutation ; Female ; Retrospective Studies ; Telomerase/genetics* ; Telomere-Binding Proteins/genetics* ; Child ; Cell Cycle Proteins/genetics* ; Nuclear Proteins/genetics* ; Child, Preschool ; Prognosis ; Exome Sequencing

OBJECTIVE: To investigate the role of nucleolin (NCL) in acute myeloid leukemia (AML) Kasumi-1 cells and its underlying mechanism. METHODS: The Kasumi-1 cells were infected with lentivirus carrying shRNA to downregulate NCL expression. Cell proliferation was detected by CCK-8 assay, and cell apoptosis and cell cycle were determined by flow cytometry. Transcriptome next-generation sequencing (NGS) was performed to predict associated signaling pathways, the expression levels of related genes were measured by RT-PCR. RESULTS: Down-regulation of NCL expression significantly inhibited the proliferation of Kasumi-1 cells (P <0.01) and markedly increased the apoptosis rate (P <0.001). Cell cycle analysis showed significant changes in the distribution of cells in the G₁ and S phases after NCL knockdown (P <0.05), while no significant difference was observed in the G₂ phase (P >0.05). Transcriptome sequencing analysis demonstrated that differentially expressed genes in Kasumi-1 cells with low expression of NCL were primarily enriched in key signaling pathways, including ribosome, spliceosome, RNA transport, cell cycle, and amino acid biosynthesis. qPCR validation showed that the expression of BAX, CASP3, CYCS, PMAIP1, TP53 , and CDKN1A was significantly upregulated after NCL downregulation (P <0.05), with CDKN1A exhibiting the most pronounced difference. CONCLUSION NCL plays a critical role in regulating the proliferation, apoptosis, and cell cycle progression of Kasumi-1 cells. The mechanism likely involves suppressing cell cycle progression through activation of the TP53-CDKN1A pathway and promoting apoptosis by upregulating apoptosis-related genes.
Humans ; Leukemia, Myeloid, Acute/pathology* ; Down-Regulation ; Cell Proliferation ; Apoptosis ; RNA-Binding Proteins/genetics* ; Nucleolin ; Cell Line, Tumor ; Phosphoproteins/metabolism* ; Cell Cycle ; Signal Transduction ; RNA, Small Interfering

OBJECTIVE: To explore the genetic basis for a girl with primary microcephaly and growth retardation. METHODS: A girl who was admitted to Guangdong Maternal and Child Health Care Hospital in was selected as the study subject. Peripheral blood samples were collected from the child and her parents. Trio whole exome sequencing was carried out, and candidate variants were verified by Sanger sequencing and bioinformatic analysis. This study was approved by the Medical Ethnics Committee of Guangdong Maternal and Child Health Care Hospital (Ethics No. 202201278). RESULTS: DNA sequencing revealed that the child has harbored compound heterozygous variants of the WDR62 gene, including a frameshifting c.2963delC (p.Pro988Argfs*80) variant in exon 24 which was inherited from the unaffected father, and a nonsense c.3163G>T (p.Glu1055*) variant in exon 26, which was inherited from her unaffected mother. Both variants were predicted to affect the reading frame of the WDR62 gene. CONCLUSION Based on the clinical manifestations, results of genetic testing and pedigree analysis, the compound heterozygous variants were predicted to underlay the pathogenesis of microcephaly and growth retardation in this child. Above discovery has expanded the mutational spectrum for WDR62-associated Primary microcephaly type 2, and facilitated genetic counseling for the family.
Female ; Humans ; Cell Cycle Proteins ; Heterozygote ; Microcephaly/genetics* ; Mutation ; Nerve Tissue Proteins/genetics* ; Pedigree

OBJECTIVE: To explore the genetic etiology of a Chinese pedigree with recurrent Joubert syndrome with negative results by whole-exome sequencing in the prior proband. METHODS: Chinese pedigree which opted elective abortion at the Women and Children's Hospital Affiliated to Chongqing Medical University in December 2024 was selected as the study subject. Whole-genome sequencing was carried out on fetal tissue after termination of pregnancy. Candidate variants were validated by Sanger sequencing and interpreted, while non-coding variant was analyzed using in silico prediction tools. RNA sequencing and cDNA sequencing were conducted on fetal brain tissue. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.2024YL045-02). RESULTS: Both the fetus and the affected child were found to harbor compound heterozygous variants of the CEP290 gene, namely c.7341dup (p.Leu2448fs*8) (pathogenic, maternally inherited) and c.1523-408G>A (likely pathogenic, paternally inherited). Both in silico analysis and fetal brain RNA sequencing confirmed aberrant RNA splicing caused by the intronic variant. CONCLUSION This case has highlighted the value of combining whole-genome sequencing with RNA functional validation. Above results not only enriched the spectrum of CEP290 gene mutations but also underscored its diagnostic value in resolving complex prenatal cases, providing critical clues for the prenatal diagnosis and recurrence risk assessment in genetic counseling.
Female ; Humans ; Pregnancy ; Abnormalities, Multiple/genetics* ; Antigens, Neoplasm/genetics* ; Cell Cycle Proteins/genetics* ; Cerebellum/abnormalities* ; Cytoskeletal Proteins/genetics* ; Eye Abnormalities/genetics* ; Introns/genetics* ; Kidney Diseases, Cystic/diagnosis* ; Pedigree ; Retina/abnormalities* ; Sequence Analysis, RNA/methods* ; Whole Genome Sequencing/methods* ; Child

OBJECTIVE: To explore the clinical features and genetic etiology of a child with Hoyeraal-Hreidarsson syndrome (HHS). METHODS: A child with HHS diagnosed at the Affiliated Hospital of Jining Medical University due to "developmental delay and anaemia" on April 27, 2024 was selected as the study subject. Clinical data of the child was collected. Genomic DNA was extracted from peripheral blood samples of the child and his family members. Whole-exome sequencing was carried out, and candidate variant was verified by Sanger sequencing of his family members and bioinformatics analysis using CASAVA v1.8.2. The pathogenicity of the candidate variant was rated according to the Standards and Guidelines for the Interpretation of Sequence Variants released by the American College of Medical Genetics and Genomics (ACMG). Relevant literature on HHS cases reported in China was reviewed to analyze the clinical and genetic characteristics. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2024-10-C003). RESULTS: The child, a 7-month-old boy, had mainly manifested with growth retardation, developmental delay, microcephaly, cerebellar hypoplasia, immunodeficiency and bone marrow failure. Routine blood test indicated pancytopenia. The immunological workup showed reduction of B cells, NK cells and immunoglobulins. Cranial MRI demonstrated the volume of bilateral cerebellar hemispheres and brainstem and corpus callosum was small. Whole-exome sequencing revealed that he has harbored a hemizygous c.103_105del (p.Glu35del) variant of the DKC1 gene. Sanger sequencing showed that his mother and two sisters have carried the same variant. Based on the ACMG guidelines, the variant was predicted to be likely pathogenic (PM1+PM4+PS4_Supporting+PM2_Supporting). Four relevant literature were retrieved, which has involved 8 HHS cases. Together with the patient from this study, they have consisted of 8 males and 1 females. The most common symptoms of the 9 patients were blood system abnormalities and developmental delay. All patients had shown cerebellar dysplasia and anemia/erythrocytopenia. Among them, 3 cases have harbored TINF2 gene variants, and 6 cases had harbored DKC1 gene variants. The c.103_105del variant has not been reported in China previously. CONCLUSION The hemizygous c.103_105del (p.Glu35del) variant of the DKC1 gene probably underlay the disease in this child. Above finding has expanded the mutational and phenotypic spectra of the DKC1 gene, and has facilitated early diagnosis of HHS in this child.
Humans ; Infant ; Male ; Cell Cycle Proteins/genetics* ; Dyskeratosis Congenita/genetics* ; Exome Sequencing ; Fetal Growth Retardation/genetics* ; Intellectual Disability/genetics* ; Microcephaly/genetics* ; Mutation ; Nuclear Proteins/genetics* ; X-Linked Intellectual Disability/genetics*

OBJECTIVES: To investigate the effect of BRD4 inhibition on migration of esophageal squamous cell carcinoma (ESCC) cells with low acetyl-CoA carboxylase 1 (ACC1) expression. METHODS: ESCC cell lines with lentivirus-mediated ACC1 knockdown or transfected with a negative control sequence (shNC) were treated with DMSO, JQ1 (a BRD4 inhibitor), co-transfection with shNC-siBRD4 or siNC with additional DMSO or C646 (an ahistone acetyltransferase inhibitor) treatment, or JQ1combined with 3-MA (an autophagy inhibitor). BRD4 mRNA expression in the cells was detected using RT-qPCR. The changes in cell proliferation, migration, autophagy, and epithelial-mesenchymal transition (EMT) were examined with CCK8 assay, Transwell migration assay, and Western blotting. RESULTS: ACC1 knockdown did not significantly affect BRD4 expression in the cells but obviously increased their sensitivity to JQ1. JQ1 treatment at 1 and 2 μmol/L significantly inhibited ESCC cell proliferation, while JQ1 at 0.2 and 2 μmol/L promoted cell migration. The cells with ACC1 knockdown and JQ1 treatment showed increased expresisons of vimentin and Slug and decreased expression of E-cadherin. BRD4 knockdown promoted migration of ESCC cells, and co-transfection with shACC1 and siBRD4 resulted in increased vimentin and Slug expressions and decreased E-cadherin expression in the cells. C646 treatment of the co-transfected cells reduced acetylation levels, decreased vimentin and Slug expressions, and increased E-cadherin expression. Treatment with JQ1 alone obviously increased LC3A/B-II levels in the cells either with or without ACC1 knockdown. In the cells with ACC1 knockdown and JQ1 treatment, additional 3-MA treatment significantly decreased the expressions of vimentin, Slug and LC3A/B-II and increased the expression of E-cadherin. CONCLUSIONS BRD4 inhibition promotes autophagy of ESCC cells via a histone acetylation-dependent mechanism, thereby enhancing EMT and ultimately increasing cell migration driven by ACC1 deficiency.
Humans ; Cell Movement ; Transcription Factors/metabolism* ; Esophageal Neoplasms/metabolism* ; Cell Line, Tumor ; Cell Cycle Proteins ; Azepines/pharmacology* ; Epithelial-Mesenchymal Transition ; Carcinoma, Squamous Cell/metabolism* ; Esophageal Squamous Cell Carcinoma ; Triazoles/pharmacology* ; Nuclear Proteins/genetics* ; Cell Proliferation ; Acetyl-CoA Carboxylase/genetics* ; Transfection ; Autophagy ; Bromodomain Containing Proteins