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

Loss-of-function variants in CSDE1 have been strongly linked to neuropsychiatric disorders, yet the precise role of CSDE1 in neurogenesis remains elusive. In this study, we demonstrate that knockout of Csde1 during cortical development in mice results in impaired neural progenitor proliferation, leading to abnormal cortical lamination and embryonic lethality. Transcriptomic analysis revealed that Csde1 upregulates the transcription of genes involved in the cell cycle network. Applying a dual thymidine-labelling approach, we further revealed prolonged cell cycle durations of neuronal progenitors in Csde1-knockout mice, with a notable extension of the G1 phase. Intersection with CLIP-seq data demonstrated that Csde1 binds to the 3' untranslated region (UTR) of mRNA transcripts encoding cell cycle genes. Particularly, we uncovered that Csde1 directly binds to the 3' UTR of mRNA transcripts encoding Cdk6, a pivotal gene in regulating the transition from the G1 to S phases of the cell cycle, thereby maintaining its stability. Collectively, this study elucidates Csde1 as a novel regulator of Cdk6, sheds new light on its critical roles in orchestrating brain development, and underscores how mutations in Csde1 may contribute to the pathogenesis of neuropsychiatric disorders.
Animals ; Neurogenesis/genetics* ; Cell Cycle/genetics* ; Mice, Knockout ; Mice ; Neural Stem Cells/metabolism* ; DNA-Binding Proteins/metabolism* ; Cyclin-Dependent Kinase 6/genetics* ; Cell Proliferation ; 3' Untranslated Regions ; Cerebral Cortex/embryology* ; RNA-Binding Proteins ; Mice, Inbred C57BL

The inhibition of cyclin-dependent kinases (CDKs) is considered a promising strategy for cancer treatment due to their role in cell cycle regulation. However, CDK inhibitors with no selectivity among CDK families have not been approved. A CDK inhibitor with high selectivity for CDK4/6 exhibited significant treatment effects on breast cancer and has become a heavy bomb on the market. Subsequently, resistance gradually decreased the efficacy of selective CDK4/6 inhibitors in breast cancer treatment. In this review, we first introduce the development of selective CDK4/6 inhibitors and then explain the role of CDK2 activation in inducing resistance to CDK4/6 inhibitors. Moreover, we focused on the development of CDK2/4/6 inhibitors and selective CDK2 inhibitors, which will aid in the discovery of novel CDK inhibitors targeting the cell cycle in the future.
Humans ; Cell Cycle/drug effects* ; Protein Kinase Inhibitors/chemistry* ; Cyclin-Dependent Kinases/metabolism* ; Neoplasms/genetics* ; Antineoplastic Agents/pharmacology* ; Animals ; Breast Neoplasms/enzymology* ; Cyclin-Dependent Kinase 4/metabolism*

Gastric cancer (GC) is characterized by high morbidity and mortality rates. Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis (Lour.) Gilg., traditionally utilized for treating asthma, cardiac ischemia, and tumors. However, comprehensive research regarding its anti-GC effects and underlying mechanisms remains limited. In this study, Chinese agarwood petroleum ether extract (CAPEE) demonstrated potent cytotoxicity against human GC cells, with half maximal inhibitory concentration (IC₅₀) values for AGS, HGC27, and MGC803 cells of 2.89, 2.46, and 2.37 μg·mL^-1, respectively, at 48 h. CAPEE significantly induced apoptosis in these GC cells, with B-cell lymphoma-2 (BCL-2) associated X protein (BAX)/BCL-2 antagonist killer 1 (BAK) likely mediating CAPEE-induced apoptosis. Furthermore, CAPEE induced G₀/G₁ phase cell cycle arrest in human GC cells via activation of the deoxyribonucleic acid (DNA) damage-p21-cyclin D1/cyclin-dependent kinase 4 (CDK4) signaling axis, and increased Fe²⁺, lipid peroxides and reactive oxygen species (ROS) levels, thereby inducing ferroptosis. Ribonucleic acid (RNA) sequencing, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blotting analyses revealed CAPEE-mediated upregulation of heme oxygenase-1 (HO-1) in human GC cells. RNA interference studies demonstrated that HO-1 knockdown reduced CAPEE sensitivity and inhibited CAPEE-induced ferroptosis in human GC cells. Additionally, CAPEE administration exhibited robust in vivo anti-GC activity without significant toxicity in nude mice while inhibiting tumor cell growth and promoting apoptosis in tumor tissues. These findings indicate that CAPEE suppresses human GC cell growth through upregulation of the DNA damage-p21-cyclin D1/CDK4 signaling axis and HO-1-mediated ferroptosis, suggesting its potential as a candidate drug for GC treatment.
Animals ; Humans ; Mice ; Antineoplastic Agents, Phytogenic ; Apoptosis/drug effects* ; Cell Line, Tumor ; Cyclin D1/genetics* ; Cyclin-Dependent Kinase 4/genetics* ; DNA Damage/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Ferroptosis/drug effects* ; G1 Phase Cell Cycle Checkpoints/drug effects* ; Heme Oxygenase-1/genetics* ; Mice, Inbred BALB C ; Mice, Nude ; Plant Extracts/pharmacology* ; Stomach Neoplasms/physiopathology* ; Thymelaeaceae/chemistry* ; Up-Regulation/drug effects*

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*

Most tumor cells and healthy neurons are at rest during G0 phase.Once the cell cycle is abnormally re-entered under certain conditions,the proliferation of tumor cells and the degenerative necrosis of neurons can be initiated.From the perspective of the cell cycle,cancer and central nervous system diseases,two seemingly different disease types,have a common pathogenesis.This type of diseases is named aberrant cell cycle diseases.As a newly discovered microRNA(miR),miR-1976 is closely related to the regulation of the cell cycle.This review summarizes the progress in the research on miR-1976 in cancer and central nervous system diseases,aiming to provide a reference for the clinical application of miR-1976 in aberrant cell cycle diseases in the future.
MicroRNAs/genetics* ; Humans ; Cell Cycle/genetics* ; Neoplasms/genetics* ; Central Nervous System Diseases/genetics*

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