Frontiers in Cell and Developmental Biology最新文献

Background: Programmed cell death 1 (PD-1) or PD-ligand 1 (PD-L1) blocker-based strategies have improved the survival outcomes of clear cell renal cell carcinomas (ccRCCs) in recent years, but only a small number of patients have benefited from them.

Methods: In this study, we developed a multi-omics machine learning model based on inflammatory and immune signatures (TIs) to predict the response and survival of ccRCC patients to immune checkpoint blockade (ICB) therapy. The research collected RNA-seq and single-cell RNA-seq (scRNA-seq) data from more than 1,900 patients with autoimmune nephropathy and analyzed the genomic and transcriptome profiles of ccRCC patients. The predictive power of the method was validated in more than 1,000 ccRCC patients treated with ICB, and compared to single biomarkers (e.g., PD-L1 expression, TMB).

Results: Inflammatory signaling was found to be strongly associated with ICB outcome, and 716 inflammation-related genes were identified that are enriched in the "lymphocyte activation regulation" pathway. The findings suggested that ccRCC patients can be categorized into two subtypes with different treatment responses and prognosis by these features. In addition, the TIs-ML model exhibited superior predictive capabilities compared to an individual biomarker (AUC > 0.997) across multiple independent datasets. It demonstrated the capacity to accurately differentiate between responders and non-responders. Furthermore, the model performed more effectively than existing genetic models and functional scores in predicting survival.

Conclusion: We propose a TIs-ML prediction model based on multi-omics features that can effectively predict ICB treatment response in ccRCC patients. The model integrates inflammatory and immune features, and its high generalization ability was validated in multiple cohorts. Overall, the TIs-ML approach provides a novel method for guiding precise immunotherapy in ccRCC.

Plasma cell mastitis (PCM), also termed ductal dilatation or periductal mastitis (PDM), is a benign, non-bacterial inflammatory breast disorder predominantly affecting non-lactating women. Its incidence continues to rise, yet diagnosis and therapeutic approaches remain under development. Consequently, elucidating the pathogenesis is essential for identifying the disease's root cause and facilitating breakthroughs. PCM is increasingly regarded as an autoimmune disorder, highlighting the crucial role of immune factors in its development; however, the precise immune mechanisms involved remain incompletely understood. Against these backgrounds, this review aims to: (1) discuss the contributions of various innate and adaptive immune cells within the PCM-associated immune microenvironment; (2) describe the relationship between imbalances in key immune cells (including M1/M2 macrophages, Th1/Th2 lymphocytes, Th17/Treg cells) and the progression of PCM; (3) explore potential future research areas, the underlying immunopathogenesis of PCM, and prospective therapeutic targets, the activation of the complement system, regulation of immune homeostasis, the role of immune cell circadian rhythms, and modulation of key immune pathways.

Skeletal muscle regeneration depends on muscle stem cells (MuSCs), in which cadherin-mediated adhesion and planar cell polarity (PCP) signaling play critical roles. M-Cadherin is the major cadherin expressed in MuSCs; however, its functional link to PCP proteins remains unclear. In this study, we demonstrate that the PCP core component Vangl2 co-localizes with M-cadherin at the MuSC-myofiber boundary and directly interacts with it in C2C12 cells. Mutagenesis analyses revealed that the catenin-binding domain of M-cadherin and the C-terminal domain of Vangl2 are required for this interaction, which uniquely enables M-cadherin to form a ternary complex with Vangl2 and β-catenin. Knockdown of Vangl2 impaired myoblast fusion, reduced the expression of MyoD and Myomixer, and decreased the cell surface stability of M- and N-cadherins, while canonical Wnt/β-catenin and Akt signaling were unaffected. These findings demonstrate that Vangl2 stabilizes cadherins at the plasma membrane and promotes myogenic differentiation, suggesting a previously unrecognized role of PCP signaling in skeletal muscle maintenance and regeneration.

Galactosemia, a genetic disorder caused by mutations in the human GALT gene, often leads to multi-organ damage, with liver injury being particularly prominent. To elucidate the molecular mechanisms of Galt in liver injury, this study employed the CRISPR/Cas9 system to construct a Galt (c.847 + 1G > T) gene-edited mouse (GAL mouse) model. Quantitative Real-time PCR and Western blotting revealed a significant reduction of Galt gene in GAL mice. Elevated liver index, serum ALT and AST levels, and H&E staining results indicated significant hepatocyte edema in GAL mice, suggesting a pronounced liver injury phenotype. Single-cell transcriptomics further unveiled significant changes in hepatocyte subtype proportions, with downregulation of metabolism-related genes and upregulation of immune-related genes. Cell communication analysis demonstrated that the communication of HGF and VEGF signaling pathways was significantly enhanced following Galt gene editing. The enhancement of HGF and VEGF signaling pathways may lead to hepatocyte edema, thereby causing liver injury. The GAL mouse model constructed in this study not only revealed the crucial roles of the Galt gene in liver metabolism, immune regulation, and cell communication, but also provided new insights into the pathogenesis of galactosemia and potential therapeutic targets.

The question of heterogeneity among adipose tissue cells and mesenchymal stem/stromal cells mesenchymal stem cells derived from white adipose tissue has long been a subject of interest. In our study, we conducted a comprehensive single-cell RNA-seq analysis on MSCs isolated from human subcutaneous adipose tissue and maintained under control conditions or upon adipogenic induction. Our findings unveiled a distinct subpopulation of T-cadherin expressing cells, which co-expressed Dipeptidyl peptidase-4 (DPP4⁺), a marker of multipotent progenitors in the adipose tissue. Moreover, T-cadherin co-expressed with DPP4⁺ in early progenitors both, in vivo and in vitro. While adipogenic induction resulted in overall T-cadherin decline, in both the control and differentiated samples, there existed cells with high T-cadherin concurrently expressing stemness-related genes. Pseudotemporal trajectories analysis based on the scRNA-seq data, revealed that T-cadherin-expressing cells constituted a discrete cell subpopulation with stem-like properties, rather than participating in adipogenic differentiation. Using lentiviral transduction, we manipulated T-cadherin expression in MSCs and found that cells overexpressing T-cadherin also displayed an elevated level of DPP4. Strikingly, these cells exhibited significantly slower rates of proliferation compared to the controls. Long-term live-cell imaging, which allowed for the tracking of individual cell fates over a span of 10 days, together with classical adipogenic differentiation assays, revealed a substantial reduction in adipogenic differentiation capacity among MSCs overexpressing T-cadherin. Consequently, our experimental findings support a compelling model wherein T-cadherin, positioned upstream of DPP4, plays a pivotal role in maintaining a stem-like status within a distinct subpopulation of T-cadherin-expressing cells within MSCs.

Aging is the primary risk factor for prostate cancer (PCa), characterized biologically by a systemic collapse of proteostasis networks. Paradoxically, rather than succumbing to this decline, PCa cells exploit it, developing a "proteostasis addiction" to cope with persistent intrinsic stress. This review elucidates this paradox through three conceptual frameworks: the dynamic transition from age-related functional decay to tumorigenic hijacking; the specificity of oncogenic protein regulation; and the functional dichotomy (or "double-edged sword") of proteostatic components in tumor suppression versus promotion. We examine how declining molecular chaperone networks are co-opted to selectively stabilize the androgen receptor (AR) and its variants. Furthermore, we explore how the ubiquitin-proteasome system (UPS) is re-engineered via E3 ligases and deubiquitinases (DUBs) to orchestrate the precise turnover of tumor suppressors and oncoproteins. Special attention is given to chaperone-mediated autophagy (CMA), which undergoes a reversal from age-associated suppression to hyperactivation in advanced PCa, thereby fueling metabolic adaptation and therapy resistance. Beyond the intracellular context, we discuss how proteostatic imbalances drive the senescence-associated secretory phenotype (SASP) to remodel the tumor microenvironment. Finally, we assess emerging therapeutic strategies, arguing that precision modulation of specific proteostasis nodes-such as distinct E3/DUBs or CMA pathways-represents a promising frontier to overcome castration-resistant prostate cancer (CRPC).

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.