Frontiers in Cell and Developmental Biology最新文献

Localization of the actin-, lipid- and mRNA-binding protein Annexin A2 (AnxA2) in dividing cells revealed its presence in large spherical structures which are confined to the cell periphery and frequently co-align with astral microtubules. These structures appear during prometaphase and disappear at telophase, coinciding with the mitotic breakdown and subsequent reformation of the nuclear lamina and envelope. Their size increases as cells progress to anaphase, while their number decreases, suggesting that they are capable of fusion. Treatment of cells with the aliphatic alcohol propylene glycol led to rapid and reversible disassembly of the structures, providing further evidence that they correspond to biomolecular condensates. Notably, the condensates enclose compartments involved in biosynthetic or endocytic membrane recycling - defined by Rab1, Rab11, or endocytosed transferrin-but lack other membrane organelles, indicating that they may serve as mitotic reservoirs for selected endomembranes. Additionally, the condensates incorporate lamin B, which connects with the pericentrosomal membrane recycling compartments during prometaphase, when the nuclear lamina disassembles in conjunction with centrosome separation. These findings show similarities between the peripheral mitotic condensates and the membranous lamin B spindle matrix which has been proposed to act in spindle organization and organelle inheritance. The separating daughter cells at late anaphase contain equal numbers of the condensates, in accordance with their potential role in mitotic partitioning of endomembranes and other cytoplasmic components.

Background: The phosphatase and tensin homolog (PTEN) is a classical tumor-suppressor gene. Its expression deficiency concurrently drives disease progression in approximately 30% of melanomas and is closely associated with radiotherapy tolerance. However, there is a lack of systematic evidence regarding whether and how PTEN regulates the radiosensitivity of melanoma.

Methods: The expression of PTEN was validated using TCGA database, clinical tissue microarrays, and multiple melanoma cell lines. PTEN knockdown (PTEN-KD) and PTEN overexpression (PTEN-OE) stable cell lines were constructed using lentiviral vectors. CCK-8, colony formation assay, annexin V/PI flow cytometry, neutral comet assay, cell-cycle analysis, and Western blotting were used to assess the biological changes in cells after 0 Gy-8 Gy γ-ray irradiation (IR). A cell-derived xenograft model was established, and the tumor volume was observed after local 10 Gy IR for 28 days; in addition, H&E, Ki67, and TUNEL evaluations were performed.

Results: The expression of PTEN in melanoma tissues and cell lines was significantly lower than that in normal controls. IR could induce a transient upregulation of PTEN followed by rapid downregulation. PTEN-OE significantly inhibited proliferation, reduced the clone survival rate, increased apoptosis, and weakened radiation-induced G₂/M phase arrest; however, the opposite was true for PTEN-KD. Mechanistically, PTEN-OE inhibited the DNA-PKcs axis, reduced NHEJ-mediated rapid repair, and increased the persistent expression of γ-H2AX. PTEN-KD activated the p-ATM/p-Chk2 signaling. Animal experiments confirmed that the tumor volume in the PTEN-OE + IR group was significantly lower than that in the NC + IR group, with an expanded necrotic area, a decreased Ki67 index, and an increased TUNEL-positive rate.

Conclusion: PTEN enhances the radiosensitivity of melanoma by inhibiting the DNA-PKcs signal, weakening NHEJ repair, and delaying cell-cycle recovery. PTEN can serve as a biomarker for radiotherapy response prediction and a target for sensitization intervention, providing an experimental basis for precise radiotherapy strategies for melanoma.

Introduction: The cryopreservation of semen from the Inner Mongolia cashmere goat, a valuable dual-purpose breed in China, results in a sharp decline in sperm motility, hindering genetic improvement and germplasm propagation. This study aimed to investigate the protective effects and underlying mechanisms of skim milk as a supplement in a cryopreservation extender.

Methods: Skim milk was added stepwise (2%-3.6%) to an egg yolk-soy lecithin basal extender, with 2.8% identified as the optimal concentration. Tandem mass tag (TMT) quantitative proteomics, coupled with parallel reaction monitoring (PRM) validation, was employed to analyze the proteomic profiles of post-thaw sperm and elucidate homeostatic mechanisms related to sperm membrane stability.

Results: The addition of 2.8% skim milk significantly increased post-thaw sperm motility to 68.23%, reduced ultrastructural abnormalities, elevated acrosomal integrity by 18.7%, and decreased lipid peroxidation by 29% (P < 0.05). Proteomic analysis identified 32 differentially expressed proteins. Gene Ontology (GO) enrichment revealed significant involvement in processes related to purine ribonucleoside triphosphate metabolism and transmembrane transporter activity. KEGG pathway analysis indicated predominant enrichment in energy metabolism and signal transduction pathways. PRM validation confirmed that proteins NDUFA8, PGAM2, ACTL7A, PRXL2B, ATP6V0C, and LELP1 exhibited expression patterns consistent with the proteomic data, serving as core biomarkers for skim milk-mediated membrane stabilization.

Discussion: This study provides the first proteomic-level evidence that skim milk enhances the cryotolerance of Inner Mongolia cashmere goat spermatozoa. The mechanism involves the modulation of an energy-membrane protein network, which stabilizes sperm membranes during cryopreservation. The identified proteins establish molecular biomarkers for optimizing semen cryopreservation protocols in this breed.

The remodeling of synapses in the hippocampus is intricately linked to processes of learning and memory. Research indicates that high-intensity interval training (HIIT) enhances cognitive functions reliant on the hippocampus in mice, although the specific receptor-mediated molecular pathways involved are not fully elucidated. Lactate, which is produced in significant amounts during HIIT, may function as a signaling agent in the brain through the lactate receptor G protein-coupled receptor 81 (GPR81), classified as a Gi-type G protein-coupled receptor. This investigation focused on the lactate/GPR81 pathway's contribution to synaptic remodeling in the hippocampus induced by HIIT and examined its downstream signaling characteristics. In vivo results demonstrated that HIIT led to an increase in dendritic spine density and presynaptic vesicle density, enhancing learning and memory; however, these structural and cognitive improvements were negated by the knockdown of GPR81 in the hippocampus. In vitro experiments with Neuro-2a (N2a) cells, when treated with a GPR81 agonist alongside an adenyl cyclase (AC) agonist, a phospholipase C (PLC) inhibitor, and an extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor, revealed that GPR81 activation resulted in elevated ERK1/2 phosphorylation and increased levels of proteins associated with synaptic remodeling. Further pharmacological interventions reinforced a dual downstream signaling mechanism that involves the inhibition of the AC pathway and the activation of the PLC pathway, both of which converge on ERK1/2. Overall, these results suggest that the lactate/GPR81 pathway is essential for the critical aspects of HIIT-induced synaptic remodeling in the hippocampus and the enhancement of memory, supporting a GPR81-dependent dual-branch model that converges on ERK1/2 in a simplified in vitro context.

Atrial fibrillation (AF) is the most common type of arrhythmia encountered in the clinical setting, and its occurrence is influenced by various factors, particularly aging. Senescence of atrial myocytes plays an important role in the development of AF, although the precise mechanisms underlying this association remain unclear. This review explores the pivotal role of atrial myocyte senescence in AF pathogenesis, moving beyond chronological age. It provides evidence that aging creates a pro-arrhythmic substrate via three interconnected mechanisms: 1) inflammatory activation (mitochondrial ROS, NLRP3, and SASP), 2) dysregulated calcium handling (RyR2 and SERCA2), and 3) cell cycle disruption (p16, p21, and p53). These pathways, compounded by epigenetic changes and SIRT1/mTOR signaling dysregulation, drive the electrical and structural remodeling that triggers and sustains AF. The review highlights promising therapeutic targets such as SIRT1 activators and NLRP3 inhibitors, proposing an integrated "senescence-AF axis" model, while identifying key research gaps in cell-type specificity and clinical translation. This comprehensive review outlines current progress in research in this area and future research directions and provides valuable references for forthcoming studies.

Introduction: Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia (AML) with unique clinical features. Flow cytometry (FCM) immunophenotyping analysis is crucial for accurate diagnosis and prognostic stratification. This study aims to explore the association between specific immune phenotype markers in APL patients and overall survival (OS).

Methods: In this retrospective cohort study, immunophenotypic data from 72 APL patients were analyzed by FCM. Continuous and categorical variables are presented as mean ± standard deviation and frequency (percentage), respectively. Group comparisons were performed using ANOVA and Chi-square tests. Cox proportional hazards models were used to identify prognostic factors for OS, with results expressed as hazard ratios (HRs) and 95% confidence intervals (CIs). Kaplan-Meier survival analysis was employed to assess the impact of CD56, CD2, CD34, and CD200 expression on OS. Subgroup analyses were conducted based on age, gender, white blood cell count (WBC), and disseminated intravascular coagulation (DIC).

Results: The baseline age (p = 0.513) and gender (p = 0.881) were comparable across different PML-RARα isoform groups. Compared to non-APL AML, APL blasts were characterized by significantly higher expression of CD33, CD13, CD9, and MPO (all p < 0.05), and lower expression of CD7, CD34, CD56, CD38, CD200, and HLA-DR (all p < 0.001). The PML-RARα (S-type) group showed relatively higher expression of CD34, CD2, and CD200 than the L-type group. Univariate Cox analysis revealed that expression of CD34, CD2, CD56, and CD200 were all significantly associated with poorer OS. After multivariate adjustment, CD2 (adjusted HR = 1.04, 95% CI: 1.01-1.07, p = 0.004) and CD200 (adjusted HR = 1.04, 95% CI: 1.01-1.06, p = 0.009) remained independent adverse prognostic factors. Subgroup analysis confirmed that the negative prognostic impact of CD2 and CD200 expression was consistent across different patient subgroups.

Conclusion: Compared with non-APL-AML patients, APL patients (PML-RARα (S-type) and PML-RARα (L-type)) exhibit unique immunophenotypic changes. The expression frequencies of CD56, CD2, CD34, and CD200 in leukemia cells are significantly correlated with the OS of APL patients, and the high expression of these indicators before treatment may be an adverse prognostic factor for APL patients.

Background: Glioblastoma (GBM) is an aggressive malignancy of the central nervous system characterized by rapid progression, therapeutic resistance, and poor prognosis. Epithelial-mesenchymal transition (EMT) contributes to tumor plasticity and immune remodeling in GBM. Identification of EMT-driving genes (EDGs) with prognostic and therapeutic relevance may provide insights into disease progression and precision management. This study aimed to systematically identify prognostic EDGs and to construct a robust EMT-based prognostic model for GBM.

Methods: Univariate Cox regression analyses were performed across five GBM cohorts (TCGA, CGGA-693, CGGA-325, GSE83300, and GSE74187) to rank genes according to hazard ratios, followed by Gene Set Enrichment Analysis (GSEA), which identified EMT as the pathway most strongly associated with adverse survival. EMT-related genes from MSigDB and dbEMT2.0 were intersected with TCGA-derived prognostic genes to obtain 145 EDGs. An EMT-related prognostic signature was generated using LASSO Cox regression and validated in independent datasets. Functional analyses, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), weighted gene co-expression network analysis (WGCNA), and GSEA, elucidated biological processes associated with the risk signature. Immune infiltration analyses (ESTIMATE, CIBERSORT) and drug sensitivity analyses characterized the tumor microenvironment and therapeutic response. Random Forest analysis and in vitro assays identified and validated GJB2 as a key mediator of GBM progression.

Results: A total of 145 EDGs were identified by integrating survival-associated genes from TCGA with EMT-related genes from MSigDB and dbEMT2.0. An EMT-related prognostic signature was developed and validated across five GBM cohorts. The risk score stratified patients into high- and low-risk groups with significantly different survival outcomes and remained an independent prognostic factor in multivariate Cox analyses. A nomogram integrating the risk score with age, IDH mutation status, and MGMT promoter methylation demonstrated strong predictive performance. Immune profiling revealed that the high-risk group exhibited an "immune-inflamed yet immunosuppressed" phenotype characterized by elevated macrophage and regulatory T-cell infiltration. Drug sensitivity analyses suggested that high-risk GBM may respond better to paclitaxel and tamoxifen. Random Forest modeling and in vitro experiments identified GJB2 as an oncogenic driver that promotes GBM cell proliferation and migration.

Conclusion: Our findings provide a clinically applicable EMT-based prognostic framework that links transcriptional plasticity to patient outcomes in GBM and identify GJB2 as a promising therapeutic target.

Malignant melanoma is an aggressive skin malignancy with a complex molecular landscape and limited treatment durability in advanced stages. Aberrations in the MAPK pathway-most notably BRAF and NRAS mutations-have catalyzed the development of targeted therapies, particularly BRAF/MEK inhibitors, which have transformed outcomes in BRAF-mutant melanoma. However, resistance remains prevalent, driven by MAPK reactivation, epigenetic rewiring, and tumor microenvironmental feedback. In NRAS-mutant subtypes, MEK inhibition, CDK4/6 blockade, and immune checkpoint inhibition offer partial efficacy, yet monotherapies fail to achieve sustained responses. Emerging strategies focus on combinatorial regimens targeting RAF-MEK-ERK and PI3K-AKT axes, alongside immunotherapeutic integration. Rarer alterations in KIT and RTKs also define actionable subsets. This review synthesizes recent mechanistic insights and therapeutic advances in mutation-driven melanoma, highlighting the promise of biomarker-guided combination strategies and signaling crosstalk disruption as the next frontier in precision oncology.

Background: Autophagy dysregulation plays an important role in the development and progression of lupus nephritis (LN). However, the key autophagy-related genes involved in LN and their underlying cellular mechanisms remain unclear. This study aims to systematically explore the autophagy-related molecular signatures of LN and to elucidate the relevant mechanisms.

Methods: Transcriptomic data from LN and control kidney tissues were analyzed to identify differentially expressed genes (DEGs), followed by KEGG, GSEA, and GSVA enrichment. Autophagy-related DEGs (ARDEGs) were obtained by intersecting DEGs with autophagy gene sets. Hub genes were screened using PPI network analysis, cytoHubba algorithms, and WGCNA. Diagnostic performance was assessed by ROC curves and a nomogram. Single-cell datasets and qRT-PCR, pathology, TEM, and immunohistochemistry were used for validation. Functional assays were conducted in CIHP-1 podocytes with stable EGFR overexpression.

Results: A total of 445 ARDEGs were identified, enriched in autophagy, PI3K-Akt/mTOR, and MAPK pathways. Eleven hub genes were obtained, among which EGFR and RAF1 showed strong diagnostic value (AUC >0.90) and correlations with immune infiltration. Single-cell and experimental validation revealed elevated EGFR expression in LN. EGFR-overexpressing podocytes exhibited increased MDC fluorescence by flow cytometry, autophagosome accumulation by TEM, and a significant increase in LC3-positive puncta by confocal microscopy.

Conclusion: EGFR is a key regulatory factor related to autophagy in LN. The excessive activation of EGFR affects the autophagy of LN podocytes, providing new mechanistic insights and potential therapeutic targets for LN.