KDM8 is a histone demethylase initially characterized for its activity on H3K36me2, although its function is now more widely recognized as a hydroxylase. Through a high-throughput screening on histone demethylases, we id...KDM8 is a histone demethylase initially characterized for its activity on H3K36me2, although its function is now more widely recognized as a hydroxylase. Through a high-throughput screening on histone demethylases, we identified KDM8 as a regulator of the γH2AX response following ionizing radiation. Experiments using specific reporter substrates revealed that KDM8 depletion increases homologous recombination (HR), while its overexpression reduces HR. This shift is counterbalanced by a concomitant decrease in non-homologous end joining (NHEJ), an effect partly independent of its demethylase activity and unrelated to cell cycle alterations. Despite this imbalance, cellular sensitivity to DNA-damaging agents - such as ionizing radiation, mitomycin C, and camptothecin - remains unchanged. FRET experiments in living cells demonstrated an interaction between KDM8 and Rad51 after DNA damage induced by camptothecin. These findings identify KDM8 as a key player in DSB repair, specifically influencing HR.
Piwi-interacting RNAs (piRNAs) and PIWI proteins are emerging key players in the regulation of cancer gene expression and tumor biology. piRNAs (24-31 nucleotides), interact with PIWI proteins to regulate gene expression...Piwi-interacting RNAs (piRNAs) and PIWI proteins are emerging key players in the regulation of cancer gene expression and tumor biology. piRNAs (24-31 nucleotides), interact with PIWI proteins to regulate gene expression epigenetic mechanisms, modulating cell proliferation, apoptosis, and metastasis. Dysregulated piRNA-PIWI axis is implicated across cancer types - breast, colorectal, genitourinary, etc., and correlates with tumor progression and poor patient outcomes. Notably, piRNAs influence cancer stem cell maintenance, contributing to tumor aggressiveness and therapeutic resistance. We also highlight the significant diagnostic and prognostic potential of piRNAs (e.g. piRNA-823) due to their unique expression profiles in cancerous tissues potentially contributing to early detection and disease monitoring. Additionally, noninvasive detection of piRNAs in extracellular vesicles offers promise for liquid biopsy applications, enabling real-time monitoring of cancer progression and treatment response. On the therapeutic front, piRNA-PIWI protein axis offers innovative avenues - modulating piRNA expression or restoring normal PIWI function can limit tumor growth, metastasis, etc. Despite cumulative evidence supporting their role in cancer, challenges remain in translating piRNA research into clinical practice (lack of standardized protocols, effective therapeutic strategies). Ongoing studies into elucidating molecular implications of piRNA-PIWI axis are crucial for tapping this axis for diagnostic and therapeutic applications.
Migrasomes are a recently discovered class of organelles, typically generated at the intersections and tips of retraction fibers (RFs) in migrating cells. These monolayer vesicular structures encapsulate a variety of bio...Migrasomes are a recently discovered class of organelles, typically generated at the intersections and tips of retraction fibers (RFs) in migrating cells. These monolayer vesicular structures encapsulate a variety of bioactive molecules and have been shown to participate in essential physiological processes, including intercellular communication, embryonic development, immune microenvironment modulation, and mitochondrial homeostasis. Beyond their physiological roles, accumulating evidence has revealed that migrasomes are also closely associated with the pathogenesis of various diseases. These include kidney and retinal damage, vascular disorders, as well as the initiation and progression of multiple tumors such as glioma, osteosarcoma, liver cancer, and pancreatic cancer. Given their emerging significance in both normal physiology and disease, migrasomes hold promise as novel biomarkers and therapeutic targets, offering new avenues for research in cell biology and translational medicine.In this review, we summarize recent advances in migrasome research, with a particular emphasis on their involvement in disease mechanisms - an area of growing importance given the current limitations in clinical treatment. We also provide perspectives on future research directions and the potential translational applications of migrasomes.
The fidelity of mitotic chromosome segregation relies on kinetochores detecting sister chromatid bi-orientation to control error correction (EC) and the spindle assembly checkpoint (SAC). The kinetochore-microtubule atta...The fidelity of mitotic chromosome segregation relies on kinetochores detecting sister chromatid bi-orientation to control error correction (EC) and the spindle assembly checkpoint (SAC). The kinetochore-microtubule attachment state needs to be decoded, the signal processed, and transduced, resulting in either stabilization or destabilization of the attachment. Although many crucial players of this process have been identified, the molecular mechanisms underlying signal integration remain an open question. Focusing on the model system , we explore the interdependent contributions of the conserved protein kinases Mps1 and Ipl1, crucial regulators of mitotic chromosome segregation. We discuss how bi-orientation reorganizes the kinetochore attachment site and we present a perspective on how these structural changes can alter kinase localization and activity.
The process of DNA replication is inherently asymmetric. While the leading strand is synthesized continuously, the lagging strand is copied in small fragments, the Okazaki fragments, requiring the repeated priming by the...The process of DNA replication is inherently asymmetric. While the leading strand is synthesized continuously, the lagging strand is copied in small fragments, the Okazaki fragments, requiring the repeated priming by the DNA polymerase alpha/Primase complex (Pol α/Pri). Current evidence is consistent with a semi-distributive model for priming in the lagging strand, as Pol α/Pri acts associated to the replisome and also as a free complex. In addition, there is a strong link between the dynamics of replication in the lagging strand and the basal activation of the replication stress response (RSR) during an unperturbed S phase. We hypothesize that the RSR monitors the generation of Okazaki fragments to control the synthesis of DNA in what we call the DNA replication control (DRC) mode of the RSR. The DRC enforces a gradual progression of DNA replication by restricting origin firing, what is necessary to establish the replication program in the cell and to prevent the appearance of genomic instability. Thus, the RSR coordinates the replication program in the cell, modulating the progression of DNA replication to prevent the exhaustion of cellular resources that would endanger the stability of the genome.
Cellular phenotypes are shaped not only by current molecular states but by transient transcriptional programs that encode prior experiences and influence future behavior. Conventional transcriptomic approaches, including...Cellular phenotypes are shaped not only by current molecular states but by transient transcriptional programs that encode prior experiences and influence future behavior. Conventional transcriptomic approaches, including bulk and single-cell RNA sequencing, provide high-resolution snapshots of gene expression but are intrinsically destructive, precluding direct linkage between past transcriptional states and downstream cellular fate. In this context, "TimeVault" introduces a fundamentally new paradigm by enabling intracellular storage of endogenous transcriptomes within living cells. By repurposing vault ribonucleoprotein particles to sequester and stabilize polyadenylated mRNA, TimeVault preserves unbiased, transcriptome-wide records of transcriptional states over timescales far exceeding native mRNA half-lives. This capability allows retrospective reconstruction of molecular histories that would otherwise be lost, bridging a critical gap between transient gene expression and long-term phenotypic outcomes. Application of TimeVault to canonical stress responses demonstrates precise temporal gating and durable transcript preservation, while its use in cancer models reveals preexisting transcriptional programs that predict drug-tolerant persister cell formation prior to therapy. These findings highlight the power of molecular memory devices to uncover causal relationships that remain invisible to conventional endpoint analyses. TimeVault establishes intracellular transcriptome archiving as a versatile tool with broad implications for developmental biology, stress adaptation, and therapeutic resistance.
Ovarian cancer, one of the most lethal gynecologic malignancies, exhibits marked tumor heterogeneity. Potassium channel modulatory factor 1 (KCMF1), a RING zinc-finger protein with E3 ubiquitin ligase activity, has been...Ovarian cancer, one of the most lethal gynecologic malignancies, exhibits marked tumor heterogeneity. Potassium channel modulatory factor 1 (KCMF1), a RING zinc-finger protein with E3 ubiquitin ligase activity, has been implicated in tumorigenesis. However, the role of KCMF1 in ovarian cancer remains unclear. In this study, we found that KCMF1 was up-regulated in ovarian cancer tissues and that high KCMF1 expression correlated with poor survival of patients. Functional assays revealed that KCMF1 knockdown suppressed cell viability, hampered cell cycle progression, and inhibited proliferation in ovarian cancer cells. Moreover, silencing KCMF1 inhibited epithelial-mesenchymal transition (EMT), migration, and invasion in vitro. In vivo experiments confirmed that KCMF1 knockdown inhibited tumor growth and metastasis in nude mice. Conversely, KCMF1 overexpression had opposite effects in vitro and in vivo. IP-LC/MS and Label-free proteomic analysis identified nucleoredoxin (NXN), a multifunctional redox-active protein, as a potential substrate of KCMF1. Silencing NXN facilitated cell proliferation, migration, and invasion through activating the β-catenin signaling pathway. Mechanistically, we discovered that KCMF1 interacted with NXN and facilitates its degradation through K63-linked ubiquitination, thereby reducing NXN expression. Taken together, our study showed that KCMF1 promotes ovarian cancer progression through NXN, and KCMF1 might be a novel target for ovarian cancer therapy.
The aim of this investigation was to identify the hub genes associated with ferroptosis in keloid. We analyzed the correlation between differentially expressed genes Yin Yang-1 (YY1) and glutathione peroxidase-4 (GPX4) w...The aim of this investigation was to identify the hub genes associated with ferroptosis in keloid. We analyzed the correlation between differentially expressed genes Yin Yang-1 (YY1) and glutathione peroxidase-4 (GPX4) with keloid by quantitative Real‑Time PCR and Western blot. Molecular biological experiments were conducted to identify the role of YY1 and GPX4 in human keloid fibroblasts (HKFs). glutathione and oxidized glutathione kit, Malondialdehyde Assay Kit and C11-BODIPY (581/591) fluorescence probe were applied to monitor ferroptosis. Gain-of-function and loss-of-function assay demonstrated that YY1 regulated proliferation, migration, fibrosis of HKFs . YY1 bind to the promoter sequence of target gene GPX4. YY1-induced HKFs ferroptosis was dependent on GPX4 pathway. Furthermore, we discovered that the UCSC Genome Browser Database included an enrichment of H3K27ac signals at the YY1 promoter region. The inhibition of proliferation, migration, fibrosis, and the activation of ferroptosis in knockdown of YY1 HKFs was reversed by EP300 overexpression.
Hypertrophic scars (HS) frequently result from severe burns, surgical procedures and other causes of deep skin damage. The impact of serum/glucocorticoid regulated kinase family member 3 (SGK3) on the formation of HS rem...Hypertrophic scars (HS) frequently result from severe burns, surgical procedures and other causes of deep skin damage. The impact of serum/glucocorticoid regulated kinase family member 3 (SGK3) on the formation of HS remains unclear. HS model rats were constructed by the scalding method. In addition, tissue samples from clinical patients were collected to detect the SGK3 levels in normal skin and HS tissues by RT-qPCR and western blotting. Human-derived HS fibroblasts (HSFBs) were isolated and identified using immunofluorescence. Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine staining and scratch assays were applied to test the ability of the HSFBs to proliferate and migrate. The influence of an SGK3 inhibitor on wound healing in rats was assessed using hematoxylin and eosin staining, Masson staining, immunofluorescence and immunohistochemistry. In addition, the levels of collagen and the proteins involved in the mitogen-activated protein kinase (MAPK)/extracellular regulated protein kinase (ERK) pathway were measured by western blotting. SGK3 was highly expressed in HS tissues. Knockdown of SGK3 resulted in reduced SGK3 levels in HSFBs. Knockdown of SGK3 reduced the proliferation and migration ability of HSFBs and suppressed cellular fibrosis. Injection with an SGK3 inhibitor reduced the burn scar area, decreased epithelial thickness and inhibited collagen deposition in rats. This inhibitor also resulted in the downregulation of collagen and MAPK/ERK pathway-related proteins. In addition, MAPK/ERK pathway agonists attenuated the effect of SGK3 inhibition, promoting HS formation while inhibiting wound healing in rats; however, MAPK inhibitors had the opposite effect. In conclusion, inhibition of SGK3 reduces the proliferation, migration and fibrosis abilities of HSFBs as well as promotes wound healing and inhibits HS formation in rats by downregulating the MAPK/ERK pathway.
Myocardial hypoxia-reoxygenation (H/R) injury is a frequently observed pathological event in various cardiovascular conditions. Despite the therapeutic promise of human umbilical cord mesenchymal stem cells (hUC-MSCs) in...Myocardial hypoxia-reoxygenation (H/R) injury is a frequently observed pathological event in various cardiovascular conditions. Despite the therapeutic promise of human umbilical cord mesenchymal stem cells (hUC-MSCs) in alleviating myocardial damage, their clinical use faces obstacles such as limited implantation efficiency, poor retention, and reduced post-transplantation viability. Exosomes secreted by hUC-MSCs have emerged as a viable alternative, potentially addressing these challenges. Nonetheless, the underlying mechanisms through which these exosomes confer cardioprotection have yet to be fully elucidated. This study aims to explore the protective effect of hUC-MSCs exosomes on myocardial H/R injury via the aryl hydrocarbon receptor (AHR)/NOD-like receptor family pyrin domain containing 3 (NLRP3) pathway and to assess their impact on immune cell phenotype conversion. hUC-MSCs exosomes significantly upregulated AHR expression, inhibited NLRP3-related inflammatory protein expression, enhanced myocardial cell survival, and reduced apoptosis. The protective effect of hUC-MSCs exosomes was abolished following AHR knockdown. Additionally, exosomes from AHR-overexpressing hUC-MSCs promoted the conversion of macrophages, dendritic cells (DCs), and T cells to an anti-inflammatory phenotype, thereby further enhancing myocardial protection. These findings indicted that exosomes from AHR-overexpressing hUC-MSCs protect myocardium via AHR/NLRP3 signaling, improving immune microenvironment and offering new therapeutic potential.
Growth hormone (GH) is given to GH-deficient but also to non-GH-deprived children to promote growth. Since standard treatment requires tedious daily injections, long-release formulations are sought. However, non-GH-defic...Growth hormone (GH) is given to GH-deficient but also to non-GH-deprived children to promote growth. Since standard treatment requires tedious daily injections, long-release formulations are sought. However, non-GH-deficient conditions require higher dosing, which could entail cancer risk. To evaluate the hepatic pro-oncogenic potential of continuous GH under non-GH-deprived conditions, mice were implanted with osmotic minipumps for 5 wk during the growth period. GH secretion and hepatic actions are sexually dimorphic, thus both sexes were studied. Body growth was assessed since birth, whereas the impact on liver, a major GH target organ, was evaluated upon treatment ending, at 8 wk of age. Used dose, 6 µg/g BW, effective when given intermittently, failed to promote growth when infused continuously. Hepatocytes presented higher PCNA-stain, indicative of proliferation, in GH-treated males. STAT5 phosphorylation, related to somatic growth and metabolic GH actions, was not affected by continuous GH levels, whereas STAT3, associated with cellular growth and proliferation, was activated in females. In males, continuous GH treatment induced a female-like hepatic expression of IGF1 and cyclin D1, as well as that of MUPs and EGFR, showing that they are regulated by GH but, moreover, by the GH continuous concentration pattern. GHR and SOCS2 mRNA levels were upregulated by continuous GH in both sexes, whereas c-myc and CIS mRNA were mainly induced in female liver. These results indicate that although continuous GH administration in the used dose is not sufficient to promote growth in non-GH-deprived conditions, it may foster hepatic molecular signatures associated with potentially prooncogenic signaling in mice.
Transposable elements (TEs) are mobile DNA sequences capable of self-replication (especially retrotransposons) within the genome, which may lead to various forms of DNA damage. The introduction of this review encompasses...Transposable elements (TEs) are mobile DNA sequences capable of self-replication (especially retrotransposons) within the genome, which may lead to various forms of DNA damage. The introduction of this review encompasses the diverse classes and subclasses of TEs, particularly emphasizing the most active TEs present in the human genome. An analysis of the retrotransposition process of TEs is presented, illustrating how this mechanism can result in DNA damage and gene rearrangements. Furthermore, the review meticulously examines the implications of TE insertions on gene expression and genomic organization, which may contribute to the development of various diseases, including cancer. The relationship between TE activation and the aging process is also explored, with an emphasis on that epigenetic modifications associated with aging can lead to the derepression of TEs, thereby promoting genomic instability and inflammation. These factors may play a significant role in the pathogenesis of age-related diseases, such as cancer, cardiovascular disorders, and neurodegenerative conditions. Finally, the review considers potential therapeutic approaches aimed at targeting TE activity to alleviate the impacts of aging and associated diseases.
Glioblastoma multiforme (GBM) is the most common form of malignant brain cancer and is generally approached with palliative intent. Preclinical studies suggest that short-term fasting may be an effective tool for enhanci...Glioblastoma multiforme (GBM) is the most common form of malignant brain cancer and is generally approached with palliative intent. Preclinical studies suggest that short-term fasting may be an effective tool for enhancing existing cancer therapies by disrupting the glucose-dependent, oncogenic phenotype of many cancers. In this study, we investigated whether a fasting-mimicking environment (FME) enhances the efficacy of an emerging proapoptotic drug, procaspase-activating compound 1 (PAC-1), in 2D and 3D GBM cell models. Ad libitum food consumption (Fed) and FME conditions were simulated by modifying glucose, ketone and serum concentrations. The FME conditions enhanced PAC-1 in U87-MG, T98G and 9L-GS monolayer experiments by significantly reducing the PAC-1 50% inhibitory concentration (IC), delaying cell growth and increasing apoptosis. Similarly, in the 3D spheroid models, the minimum concentration of PAC-1 required to reduce U87-MG and 9L-GS spheroid area was lower in the FME conditions than the Fed conditions. Additionally, we discovered that serum restriction was primarily responsible for the FME-induced PAC-1 enhancement. These finding are the first to demonstrate that fasting-mimicking conditions sensitize 2D and 3D glioma cell models to PAC-1, supporting the use of short-term fasting as a low-cost and widely accessible strategy for enhancing cancer therapies.
The ability of tumor cells to migrate and invade adjacent tissue is a key property underlying the metastatic process. To ensure greater deformability and to facilitate movement, migratory cells undergo multiple changes i...The ability of tumor cells to migrate and invade adjacent tissue is a key property underlying the metastatic process. To ensure greater deformability and to facilitate movement, migratory cells undergo multiple changes in biophysical parameters, including those of stiffness and membrane viscosity. However, reports on correlations between cell motility and stiffness, or between cell motility and membrane microviscosity are rather limited and conflicting. Here, using atomic force microscopy (AFM) and fluorescence lifetime imaging (FLIM), we have investigated alterations in the mechanical properties of cancer cells and in the microviscosity of their plasma membranes that are associated with the migration process. It was found that upon activation of migration either through a "wound healing" test or by inducing epithelial-mesenchymal transition, human colorectal cancer cells undergo profound biomechanical remodeling characterized by simultaneous decreases in cell stiffness and in plasma membrane microviscosity. Our findings, therefore, support the results of previous studies that have shown cell softening and membrane fluidization to be critical adaptive responses enabling cell movement and that these can be regarded as potential biomarkers of tumor cell motility, offering scope for identifying new therapeutic targets.