The circadian clock is a highly conserved timekeeping system in organisms, which maintains physiological homeostasis by precisely regulating periodic fluctuations in gene expression. Substantial clinical and experimental evidence has established a close association between circadian rhythm disruption and the development of various malignancies. Research has revealed characteristic alterations in the circadian gene expression profiles in tumor tissues, primarily manifested as a dysfunction of core clock components (particularly circadian locomotor output cycles kaput (CLOCK) and brain and muscle ARNT-like 1 (BMAL1)) and the widespread dysregulation of their downstream target genes. Notably, CLOCK demonstrates non-canonical oncogenic functions, including epigenetic regulation via histone acetyltransferase activity and the circadian-independent modulation of cancer pathways. This review systematically elaborates on the oncogenic mechanisms mediated by CLOCK/BMAL1, encompassing multidimensional effects such as cell cycle control, DNA damage response, metabolic reprogramming, and tumor microenvironment (TME) remodeling. Regarding the therapeutic strategies, we focus on cutting-edge approaches such as chrononutritional interventions, chronopharmacological modulation, and treatment regimen optimization, along with a discussion of future perspectives. The research breakthroughs highlighted in this work not only deepen our understanding of the crucial role of circadian regulation in cancer biology but also provide novel insights for the development of chronotherapeutic oncology, particularly through targeting the non-canonical functions of circadian proteins to develop innovative anti-cancer strategies.
Humans ; ARNTL Transcription Factors/physiology* ; Neoplasms/therapy* ; CLOCK Proteins/physiology* ; Circadian Clocks/genetics* ; Animals ; Circadian Rhythm/genetics* ; Tumor Microenvironment ; Epigenesis, Genetic ; Gene Expression Regulation, Neoplastic

OBJECTIVES: To study the effect of CDC20 knockdown on proliferation, migration and invasion of cervical cancer cells and its underlying mechanism. METHODS: CDC20 expression in cervical cancer tissues was analyzed using the TCGA database, and the protein expressions of CDC20 and β-Catenin in clinical specimens of cervical cancer and adjacent tissues were detected using immunohistochemistry. A dual target sgRNA2&7 sequence for CDC20 gene was designed for CDC20 gene knockdown in cervical cancer C33A cells using CRISPR/Cas9 technology, and CDC20 mRNA and protein expression levels in the transfected cells were detected using qRT-PCR and Western blotting. The changes in proliferation, cell cycle, apoptosis, migration and invasiveness of the transfected cells were evaluated using colony-forming assay, fluorescence activated cell sorting (FACS) and Transwell assay. In the animal experiment, naïve C33A cells and the cells with CDC20 knockdown were injected subcutaneously into the left and right axillae of nude mice (n=5) to observe tumor growth. The expressions of CDC20 and β-Catenin proteins in transfected cells and the xenograft were analyzed using Western blotting, and their interaction was confirmed by co-immunoprecipitation (CoIP) and immunofluorescence co-localization assays. RESULTS: Cervical cancer tissues expressed significantly higher CDC20 and β‑Catenin levels than the adjacent tissues. C33A cells with CDC20 knockdown showed reduced proliferation, increased apoptosis, and lowered migration and invasion abilities. CDC20 knockdown significantly suppressed the growth of C33A cell xenograft in nude mice, and the tumor-bearing mice did not exhibit obvious body mass changes. CDC20 and β-Catenin levels were both significantly lowered in C33A cells with CDC20 knockdown. Co-immunoprecipitation and co-localization assays confirmed the interaction between CDC20 and β‑Catenin. CONCLUSIONS CDC20 is highly expressed in cervical cancer tissues, and CDC20 knockdown can suppress proliferation, invasion, and metastasis while enhancing apoptosis of C33A cells, which is closely related with the regulation of the Wnt/β-Catenin signaling pathway.
Humans ; Uterine Cervical Neoplasms/metabolism* ; Female ; Cdc20 Proteins/genetics* ; Cell Proliferation ; Animals ; Cell Movement ; Neoplasm Invasiveness ; Apoptosis ; Mice, Nude ; beta Catenin/metabolism* ; CRISPR-Cas Systems ; Mice ; Cell Line, Tumor ; Gene Knockout Techniques ; Neoplasm Metastasis

Epigenetics is the link between the genome and environment, which can respond to physiological (such as age) or environmental factors (such as diet, stress, and pollution) and induce changes in epigenetic modifications (such as DNA methylation, non-coding RNA, and histone modifications). It can also serve as cellular memory transmitted from generation to generation. Sperm is highly responsive to such environmental changes and has unique epigenetic profiles. The paternal inter-/trans-generational inheritance mediated by sperm epigenetic changes is closely related to the health of offspring, which is an issue of great concern. This review has summarized the epigenetic mechanisms of paternal inter-/trans-generational inheritance and recent studies on the paternal inheritance mediated by sperm epigenetic changes in human and mice, which may facilitate understanding of the relationship between paternal epigenetic changes and the health of offspring caused by physiological or environmental changes and provide a basis for genetic counseling and clinical intervention.
Epigenesis, Genetic ; Humans ; Male ; Animals ; Spermatozoa/metabolism* ; DNA Methylation ; Paternal Inheritance ; Mice

OBJECTIVE: To investigate the X-chromosome inactivation (XCI) patterns and origin in four children with Rett syndrome (RTT), and to explore the genetic basis of their phenotypic variability. METHODS: Four pediatric RTT cases diagnosed at Northwest Women's and Children's Hospital between August 1, 2022 and October 31, 2024 were enrolled. Clinical data were collected, and whole exome sequencing (WES) and Sanger sequencing were performed on the children and their parents to identify pathogenic variants. XCI analysis and linkage studies were conducted to determine the origin of variants and assess skewed XCI. This study was approved by the Medical Ethics Committee of the Northwest Women's and Children's Hospital (Ethics No. 21-036). RESULTS: WES and Sanger sequencing revealed that the four children carried the following MECP2 (NM_001110792.2) variants. c.916C>T (p.Arg306Cys), c.842delG (p.G281Afs*20), c.763C>T (p.R255X), and c.686C>T (p.Pro229Leu). The c.916C>T variant was maternally inherited, while the other three were de novo. All four variants have been previously reported: c.916C>T, c.842delG, and c.763C>T were classified as pathogenic, whereas c.686C>T was deemed likely pathogenic. XCI analysis demonstrated skewed inactivation in child 2 and 3 and their mothers, with maternal X-chromosome recombination during gametogenesis observed in child 3. All variants were located on the maternal X chromosome. CONCLUSION Skewed XCI is a common pathogenic mechanism in MECP2-related RTT, and MECP2 variants may exhibit a maternal origin bias. Clinical evaluation should incorporate XCI status for comprehensive genetic analysis.
Child ; Humans ; Chromosomes, Human, X/genetics* ; Exome Sequencing ; Methyl-CpG-Binding Protein 2/genetics* ; Mutation ; Rett Syndrome/genetics* ; X Chromosome Inactivation/genetics*

The exploration of pathogenic single nucleotide polymorphisms in the genome plays a pivotal role in the study of human disease-associated genetic mutations. However, there remains a lack of suitable high-throughput screening platforms to investigate the impact of point mutations on genomic structure and function. CRISPR/Cas9-mediated base editors has enabled large-scale annotation of the human genome and phenotypic characterization of monogenic disorders. Base editors, a precise gene-editing technique capable of achieving targeted base substitutions, can be employed to induce mutations at specific functional sites, thereby observing their effects on gene expression, protein function, and cellular phenotypes. Furthermore, integrating base editors with high-throughput screening technologies allows for large-scale evaluation of multiple candidate sites, accelerating the identification of functional loci and providing a powerful tool for disease research and therapeutic target discovery. This article aims to introduce the working principles of various base editors, including cytosine base editors, adenine base editors, and prime editors, and summarize recent advances in high-throughput screening of functional genomic sites using base-editing techniques.
Humans ; Gene Editing/methods* ; CRISPR-Cas Systems/genetics* ; Genome, Human ; Polymorphism, Single Nucleotide

In recent years, with the development of single-cell sequencing technology, spatial transcriptome technology and in vivo tracing technology, scientists have a deeper understanding of scientific issues about the in vivo development, functional regulation and ex vivo expansion of hematopoietic stem cells (HSCs). Among them, epigenetic modification plays an important role in the development and fate decisions, function maintenance and ex vivo expansion of HSCs, which has become a research hotspot in the field of stem cells in recent years. This article reviews the recent research progress of epigenetic modification in the development, functional regulation and expansion of HSCs.
Hematopoietic Stem Cells ; Epigenesis, Genetic ; Humans ; DNA Methylation

OBJECTIVE: To identify the role of gene silencing or overexpression of Nemo-like kinase (NLK) during the process of neural differentiation of human mesenchymal stem cells (hBMSCs), and to explore the effect of NLK downregulation by transfection of small interfering RNA (siRNA) on promoting neuralized tissue engineered bone regeneration. METHODS: NLK-knockdown hBMSCs were established by transfection of siRNA (the experimental group was transfected with siRNA silencing the NLK gene, the control group was transfected with control siRNA and labeled as negative control group), and NLK-overexpression hBMSCs were established using lentivirus vector transfection technique (the experimental group was infected with lentivirus overexpressing the NLK gene, the control group was infected with an empty vector lentivirus and labeled as the empty vector group). After neurogenic induction, quantitative real-time polymerase chain reaction (qPCR) was used to detect the expression of neural-related gene, and Western blot as well as immunofluorescence staining about several specific neural markers were used to evaluate the neural differentiation ability of hBMSCs.6-week-old male nude mice were divided into 4 groups: ① β-tricalcium phosphate (β-TCP) group, ② β-TCP+ osteogenic induced hBMSCs group, ③ β-TCP+ siRNA-negative control (siRNA-NC) transfection hBMSCs group, ④ β-TCP+ siRNA-NLK transfection hBMSCs group. Four weeks after the subcutaneous ectopic osteogenesis models were established, the osteogenesis and neurogenesis were detected by hematoxylin-eosin (HE) staining, Masson staining and tissue immunofluorescence assay. Statistical analysis was conducted by independent sample t test. RESULTS: After gene silencing of NLK by siRNA in hBMSCs, neural-related genes, including the class Ⅲ β-tubulin (TUBB3), microtubule association protein-2 (MAP2), soluble protein-100 (S100), nestin (NES), NG2 proteoglycan (NG2) and calcitonin gene-related peptide (CGRP), were increased significantly in NLK-knockdown hBMSCs compared with the negative control group(P < 0.05), and the expression levels of TUBB3 and MAP2 of the NLK silencing group were also increased. Oppositely, after NLK was overexpressed using lentivirus vector transfection technique, TUBB3, MAP2, S100 and NG2 were significantly decreased in NLK-overexpression hBMSCs compared with the empty vector group (P < 0.05), and the expression level of TUBB3 was also decreased. 4 weeks after the subcutaneous ectopic osteogenesis model was established, more mineralized tissues were formed in the β-TCP+ siRNA-NLK transfection hBMSCs group compared with the other three groups, and the expression of BMP2 and S100 was higher in the β-TCP+ siRNA-NLK transfection hBMSCs group than in the other groups. CONCLUSION Gene silencing of NLK by siRNA promoted the ability of neural differentiation of hBMSCs in vitro and promoted neuralized tissue engineered bone formation in subcutaneous ectopic osteogenic models in vivo in nude mice.
Bone Regeneration/genetics* ; Animals ; Mesenchymal Stem Cells/cytology* ; Humans ; RNA, Small Interfering/genetics* ; Tissue Engineering/methods* ; Cell Differentiation ; Mice, Nude ; Gene Silencing ; Mice ; Male ; Protein Serine-Threonine Kinases/genetics* ; Intracellular Signaling Peptides and Proteins/genetics* ; Transfection ; Cells, Cultured ; Lentivirus/genetics*

OBJECTIVES: The purinergic receptor P2X2 (P2RX2) encodes an ATP-gated ion channel permeable to Na⁺, K⁺, and especially Ca²⁺. Loss-of-function mutations in P2RX2 are known to cause autosomal dominant nonsyndromic deafness 41 (DFNA41), which manifests as high-frequency hearing loss, accelerated presbycusis, and increased susceptibility to noise-induced damage. Zebrafish, owing to their small size, rapid development, high fecundity, transparent embryos, and high gene conservation with humans, provide an ideal model for studying human diseases and developmental mechanisms. This study aims to generate a p2rx2 knockout zebrafish model using CRISPR/Cas9 gene editing system to investigate the effect of p2rx2 deficiency on the auditory system, providing a basis for understanding P2RX2-related hearing loss and developing gene therapy strategies. METHODS: Two CRISPR targets (sgRNA1 and sgRNA2) spaced 47 bp apart were designed within the zebrafish p2rx2 gene. Synthesized sgRNAs and Cas9 protein were microinjected into single-cell stage Tübingen (TU)-strain zebrafish embryos. PCR and gel electrophoresis verified editing efficiency at 36 hours post-fertilization (hpf). Surviving embryos were raised to adulthood (F0), tail-clipped, genotyped, and screened for positive mosaics. F1 heterozygotes were generated by outcrossing, and F2 homozygous mutants were obtained by intercrossing. Polymerase chain reaction (PCR) combined with sequencing verified mutation type and heritability. At 5 days post-fertilization (dpf), YO-PRO-1 staining was used to examine hair cell morphology and count in lateral line neuromasts and the otolith region. Auditory evoked potential (AEP) thresholds at 600, 800, 1 000, and 2 000 Hz were measured in nine 4-month-old wild type and mutant zebrafish per group. RESULTS: A stable p2rx2 knockout zebrafish line was successfully established. Sequencing revealed a 66 bp insertion at the first target site introducing a premature stop codon (TAA), leading to early termination of protein translation and loss of function. Embryos developed normally with no gross malformations. At 5 dpf, mutants exhibited significantly reduced hair cell density in the otolith region compared with wild type, although lateral line neuromasts were unaffected. AEP testing showed significantly elevated auditory thresholds at all 4 frequencies in homozygous mutants compared with wild type (all P<0.001), indicating reduced hearing sensitivity. CONCLUSIONS We successfully generated a p2rx2 loss-of-function zebrafish model using CRISPR/Cas9 technology. p2rx2 deficiency caused hair cell defects in the otolith region and increased auditory thresholds across frequencies, indicating its key role in maintaining zebrafish auditory hair cell function and hearing perception. The phenotype's restriction to the otolith region suggests tissue-specific roles of p2rx2 in sensory organs. This model provides a valuable tool for elucidating the molecular mechanisms of P2RX2-related hearing loss and for screening otoprotective drugs and developing gene therapies.
Animals ; Zebrafish/genetics* ; Receptors, Purinergic P2X2/deficiency* ; CRISPR-Cas Systems/genetics* ; Gene Knockout Techniques ; Phenotype ; Zebrafish Proteins/genetics* ; Disease Models, Animal

Neuropsychiatric disorders arise from complex interactions between genetic and environmental factors. DNA methylation, a reversible and environmentally responsive epigenetic regulatory mechanism, serves as a crucial bridge linking environmental exposure, gene expression regulation, and neurobehavioral outcomes. During long-duration deep-space missions, astronauts face multiple stressors-including microgravity, cosmic radiation, circadian rhythm disruption, and social isolation, which can induce alterations in DNA methylation and increase the risk of neuropsychiatric disorders. Genome-wide DNA methylation research can be divided into 3 major methodological stages: Study design, sample preparation and detection, and data analysis, each of which can be applied to astronaut neuropsychiatric health monitoring. Systematic comparison of the Illumina MethylationEPIC array and whole-genome bisulfite sequencing reveals their complementary strengths in terms of genomic coverage, resolution, cost, and application scenarios: the array method is cost-effective and suitable for large-scale population studies and longitudinal monitoring, whereas sequencing provides higher resolution and coverage and is more suitable for constructing detailed methylation maps and characterizing individual variation. Furthermore, emerging technologies such as single-cell methylation sequencing, nanopore long-read sequencing, and machine-learning-based multi-omics integration are expected to greatly enhance the precision and interpretability of epigenetic studies. These methodological advances provide key support for establishing DNA-methylation-based monitoring systems for neuropsychiatric risk in astronauts and lay an epigenetic foundation for safeguarding neuropsychiatric health during future long-term deep-space missions.
DNA Methylation ; Humans ; Space Flight ; Mental Disorders/genetics* ; Epigenesis, Genetic ; Astronauts/psychology* ; Weightlessness/adverse effects* ; Epigenomics

Imprinted genes play a key role in regulating mammalian placental and embryonic development. Here, we generated glutaminyl-peptide cyclotransferase-knockout (Qpct^-/-) mice utilizing the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) platform and identified Qpct as a novel anti-angiogenic factor in regulating mouse placentation. Compared with Qpct^+/+ mice, placentae and embryos (Qpct^-/+ and Qpct^-/-) showed significant overgrowth at embryonic Day 12.5 (E12.5), E15.5, and E18.5. Using single-cell transcriptome analysis of 32 309 cells from Qpct^+/+ and Qpct^-/- mouse placentae, we identified 13 cell clusters via single-nucleus RNA sequencing (snRNA-seq) (8880 Qpct^+/+ and 13 577 Qpct^-/- cells) and 20 cell clusters via single-cell RNA sequencing (scRNA-seq) (6567 Qpct^+/+ and 3285 Qpct^-/- cells). Furthermore, we observed a global up-regulation of pro-angiogenic genes in the Qpct^-/- background. Immunohistochemistry assays revealed a notable increase in the number of blood vessels in the decidual and labyrinthine layers of E15.5 Qpct^-/+ and Qpct^-/- mice. Moreover, the elevation of multiple pairs of ligand-receptor interactions was observed in decidual cells, endothelial cells, and macrophages, promoting angiogenesis and inflammatory response. Our findings indicate that loss of maternal Qpct leads to altered phenotypic characteristics of placentae and embryos and promotes angiogenesis in murine placentae.
Animals ; Female ; Pregnancy ; Mice ; Placentation/genetics* ; Single-Cell Analysis ; Gene Expression Profiling ; Mice, Knockout ; Transcriptome ; Placenta/blood supply* ; Neovascularization, Pathologic/genetics* ; Genomic Imprinting ; Single-Cell Gene Expression Analysis ; Angiogenesis