Immune checkpoint inhibitors (ICIs) are widely used in cancer treatment but can cause severe cardiotoxicity. Anti-inflammatory and cardioprotective effects of sinomenine have been documented in existing research. However, it remains unclear what role sinomenine plays in myocardial injury induced by PD-1 inhibitors. Myocardial injury in mice, induced by PD-1 inhibitors, was used to establish an experimental model. After administering sinomenine to the mice, assessments of cardiac function were conducted using echocardiographic techniques. Histological examination and ELISA were performed to evaluate myocardial injury, inflammation, and mitochondrial dysfunction. The expression of key proteins in the TLR4/NF-κB pathway was determined via Western blotting. Treatment with sinomenine notably enhanced cardiac function and mitigated myocardial injury in mice subjected to PD-1 inhibitors. It also attenuated myocardial inflammation and mitochondrial dysfunction. Mechanistic studies shed light on the fact that the activation of the TLR4/NF-κB pathway was inhibited by sinomenine. The alleviation of PD-1 inhibitor-induced myocardial injury by sinomenine is achieved through the reduction of inflammation and the restoration of mitochondrial function, with this process being regulated by the inhibition of the TLR4/NF-κB signaling pathway. These observations imply that sinomenine has the potential to serve as a therapeutic option for managing cardiotoxicity linked to immune checkpoint inhibitors.
Various cellular stressors inhibit translation initiation and promote ribosome disassembly, thereby transiently inducing stress granules (SGs), dynamic ribonucleoprotein condensates that contain mRNAs and RNA-binding proteins. Although SG assembly is usually reversible, dysregulated SG dynamics can trigger the formation of persistent ubiquitin-positive protein inclusions. There is increasing evidence that this conversion of SGs into insoluble aggregates represents a central pathogenic mechanism in neurodegenerative proteinopathies, such as amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD). TAR DNA-binding protein 43 (TDP-43) and Tau are causative factors in ALS and AD, respectively, and both localize to SGs under stress conditions. During disease progression, TDP-43 or Tau within SGs undergoes pathological changes that promote the formation of neurotoxic inclusions, which propagate neuronal dysfunction and death. This review summarizes recent advances in understanding the molecular factors that regulate SG assembly and disassembly, as well as the pathological processes that drive the conversion of SGs into aggregates associated with neurodegenerative diseases. Particular emphasis is placed on the role of the ubiquitin-specific protease 10 (USP10), which modulates SG dynamics and has been mechanistically implicated in both ALS and AD. Finally, we discuss the therapeutic potential of targeting these pathways to mitigate neurodegenerative disease progression.
Pyruvate kinase M (PKM) catalyzes the conversion of phosphoenolpyruvate to pyruvate in glycolysis and exists as two splice isoforms, PKM1 and PKM2, generated from alternative splicing of mutually exclusive exons 9 or 10, respectively. The expression balance between PKM1 and PKM2 is tightly regulated in a cell-type-specific manner. PKM1 is predominantly expressed in tissues such as skeletal muscle, heart, and brain, whereas PKM2 is prevalent in most other tissues and various cancer cells. Despite its importance, the trans-acting factors promoting exon 9 selection in a tissue-specific context remain largely unknown. Here, using a multi-color splicing reporter system for cell-based cDNA screening, we identified PUF60 as a novel trans-acting factor that promotes PKM1-type splicing. We also demonstrated that PUF60 induction and the resulting splicing switch are essential for myotube formation during C2C12 differentiation. This study establishes PUF60 as a critical regulator of muscle-specific splicing and provides new insights into the fundamental mechanisms governing skeletal muscle differentiation.
Colorectal cancer (CRC) remains one of the most frequently diagnosed and lethal malignancies. Recent studies showed that either adipose-derived mesenchymal stem cells (adMSCs) or the extracellular vesicles (EVs) they secrete retarded CRC progression. Here, we investigated the mechanism underlying the role of adMSCs-EVs in CRC. Here, we found that Krüppel-like factor 11 (KLF11) was upregulated in adMSCs-EVs. adMSCs-EVssh-KLF11 (EVs derived from KLF11-depleted adMSCs) effectively promoted lipogenesis, cell viability, proliferation, migration, and invasion of CRC cells, and accelerated tumor growth in mice. Furthermore, KLF11 carried by adMSCs-EVs dampened the PI3K/AKT signaling pathway by transcriptionally repressing sterol o-acyltransferase 1 (SOAT1) expression. SOAT1 knockdown blocked the enhanced lipogenesis, proliferation, migration and invasion induced by adMSCs-EVssh-KLF11. In conclusion, KLF11 derived from adMSCs-EVs inactivated the PI3K/AKT signaling pathway by transcriptionally downregulating SOAT1, therefore suppressing lipogenesis and malignant progression of CRC.
As tumors expand and encounter hypoxia and nutrient deprivation, cancer cells must establish tight coordination between metabolic reprogramming, protein synthesis and secretory activity to enable effective adaptation. The mechanistic target of rapamycin (mTOR) pathway plays a major role in coordinating protein synthesis and energy metabolism. Dysregulation of mTOR signaling is a hallmark of neoplasia and it contributes to tumorigenesis, metastasis, and therapeutic resistance. In this review, we discuss the emerging role of mTOR in shaping the cancer secretome and examine the implications of mTOR-dependent secretory regulation within the tumor microenvironment. Specifically, we highlight how alterations in secretory output downstream of mTOR influence extracellular matrix remodeling, angiogenesis, immune evasion, and the development of chemoresistance. This review integrates current evidence to provide a comprehensive perspective on the intersection between mTOR signaling, metabolism, protein synthesis and secretory remodeling in cancer. Specifically, we emphasize emerging links between aberrant mTOR function in cancer and secretory programs in the context of cancer cell plasticity and therapeutic resistance.
Gene expression regulated through a set of transcription factors orchestrates the physiologic processes that drive mammary gland development, breast cancer oncogenesis, and breast cancer progression. This review highlights recent progress in our understanding of how transcriptional regulators mediate mammary gland development, mammary oncogenesis and maintenance of breast cancer stem cells, breast cancer phenotype, metastasis, and efforts to target transcription factors as a therapeutic approach in breast cancer.
This research aims to investigate how aberrantly expressed miR-25-3p and EZH2 regulate T cell activation in aplastic anemia (AA) patients and to explore the underlying mechanisms. The study enrolled 26 severe AA (SAA) patients and 22 healthy subjects. Quantitative reverse transcription polymerase chain reaction was used to detect the miR-25-3p, EZH2 and CD69 expression. After establishing an AA mouse model, cell viability, proteins expression levels and cytokines levels were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Western blot analysis, and enzyme-linked immunosorbent assay. A luciferase reporter assay was performed to verify the interaction between miR-25-3p and EZH2. Serum miR-25-3p expression was decreased in SAA patients (P < 0.001). Overexpression of miR-25-3p reduced cell viability and decreased CD69, interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) levels; conversely, inhibition of miR-25-3p exerted the opposite effect (P < 0.001). EZH2 was a downstream target gene of miR-25-3p. Overexpression of EZH2 partially reversed the decrease in cell viability and the inhibition of CD69, IFN-γ and TNF-α levels caused by miR-25-3p upregulation (P < 0.01). MiR-25-3p was downregulated in SAA patients and regulated CD4+ T cell activation and proliferation by targeting EZH2. These findings provide novel insights into potential therapeutic targets for AA.
Facilitates chromatin transcription (FACT) is an evolutionarily conserved chromatin remodeling factor. It controls chromatin states in an ATP-independent manner via the regulation of chromatin assembly and disassembly. Through such regulation, FACT is involved in controlling transcription and other DNA-transacting processes such as replication and repair. However, it is surprisingly found to be upregulated in various cancers, and upregulated FACT induces oncogenesis and supports cancer cell survival, aggressiveness and metastasis, thus implying it to be a prognostic marker for cancer with an attractive targeted therapeutic potential. Here, we describe the involvement of FACT in various cancers with mechanistic insights and potential targeted therapeutic implications.
A critical developmental process affecting aging and age-associated disease, cell senescence is characterized by persistent growth arrest and adaptive gene expression patterns. A common RNA modification, N6-methyladenosine (m6A), regulates gene expression profiles but its impact on senescence has not been studied globally. Here, we elucidated the m6A landscape in proliferating and senescent human fibroblasts using epitranscriptomic microarray and m6A-crosslinking and immunoprecipitation followed by sequencing (CLIP-Seq) analyses. Our findings revealed that while global m6A levels remain stable between proliferating and senescent cells, several transcripts display altered methylation patterns, particularly in senescence-associated pathways like cell cycle, DNA repair, and inflammation. We observed that m6A deposition shifted toward 3'-untranslated regions (UTRs) in senescent cells, although the m6A site modified (the DRACH motif) was unchanged, and we found a positive correlation between m6A levels and transcript abundance. Interestingly, m6A was particularly enriched in mRNAs encoding senescence-associated secretory phenotype (SASP) factors, and silencing METTL3, a major m6A methyltransferase, reduced the stability of certain SASP mRNAs such as IL6 mRNA, suggesting a selective function of m6A in fine-tuning the senescent transcriptome. These findings provide insights into the epitranscriptomic regulation of senescence, and highlight m6A as a potential intervention target in age-related conditions influenced by senescent cells.
Noncoding RNAs are emerging players in cell signaling and diseases. Recently, we discovered a series of novel lncRNAs that are critical players in inflammation. Here, we demonstrate that hLinfRNA7, a long human noncoding inflammation-associated RNA 7 (also termed as IDO1-AS6.4) located on the antisense-strand of IDO1 (Indoleamine-2,3 -dioxygenase 1, a tryptophan catabolizing enzyme), plays critical roles in the regulation of inflammation and tryptophan (Trp) catabolism. Our studies demonstrated that hLinfRNA7 expression is induced in human THP1-derived macrophages under inflammation (LPS or IFNγ- stimulation) and is localized in the nucleus. hLinfRNA7 knockdown suppressed LPS-induced IL-6, IL-1β, and iNOS expression and reduced nitric oxide production. Interestingly, hLinfRNA7 knockdown also downregulated the inflammation-induced expression of IDO1 as well as the tryptophan catabolite kynurenine level in macrophages, suggesting critical roles of hLinfRNA7 in inflammation, cytokine regulation, and Trp-catabolism. Furthermore, IDO1 also regulate hLinfRNA7 expression, suggesting their interplay in inflammation and Trp-catabolism. hLinfRNA7 also modulates NF-κB signaling and interacts with an RNA-binding protein, YBX1, which also regulates cytokines, IDO1, hLinfRNA7, and Trp-catabolism under inflammation. Our study demonstrates lncRNA hLinfRNA7 is a novel regulator of inflammation and tryptophan catabolism. By delineating an hLinfRNA7-YBX1-IDO1 axis, our study expands lncRNA roles in immune-metabolic control and inflammatory disease.
Small-molecule inhibitors represent a novel potential therapeutic for tumors. Our previous work identified SIC-19, a small molecule compound that induces degradation of salt-inducible kinase 2 (SIK2), leading to apoptosis and reduced proliferation in tumor, expecting to be a promising clinical treatment for ovarian cancer. While we initially observed that SIC-19 triggers SIK2 ubiquitination, the underlying mechanism was unknown. Here we elucidate this process by demonstrating that SIC-19 promotes the interaction between SIK2 and the CUL4B-DDB1 E3 ubiquitin ligase. Mass spectrometry discovered several ubiquitin ligases that bind to SIK2. Immunoprecipitation assays revealed that the CUL4B-DDB1 ligase is an interaction partner of SIK2. Through Western blot analysis, we demonstrated that CUL4B is functionally required for SIC-19-induced ubiquitination and SIK2 degradation. The ubiquitination and half-life of SIK2 are directly correlated with the dosage of SIC-19 and the expression of CUL4B. Site-directed mutagenesis and ubiquitination assays further confirmed that lysine 144 (K144) is the critical residue in SIK2 that regulates cancer behavior as cell proliferation and migration by leading to the degradation of SIK2. Our findings define a novel mechanism wherein SIC-19 induces CUL4B-dependent ubiquitination and degradation of SIK2, possesses the potential to act as an inhibitor, and may subsequently be developed as a targeted agent.
Nuclear envelope (NE) proteins are essential for maintaining nuclear morphology, a central process controlling cellular phenotypes. While these proteins and structures are largely characterized in developmental biology, their function and associated abnormal nuclear morphology in disease, in particular cancer, remain elusive. We reported that throughout pancreatic transformation, oncogenic mutant KRAS (mKRAS) alters cancer cells nuclear size. Furthermore, we identified the NE protein Emerin as a mediator of these nuclear changes. Emerin's function is versatile and dynamic depending on its protein interactions. Here, using a BioID approach we identified the NE protein, Nesprin-3, as a novel Emerin interactor in mKRAS pancreatic cancer cells. Transcriptomic and epigenomic analyses revealed that mKRAS increases Nesprin-3 expression using the transcription factor KLF5 as an effector. Functional studies demonstrated that Nesprin-3 phenocopies Emerin, where knockdown of Nesprin-3 impaired nuclear morphology, proliferation, and gene expression changes induced by mKRAS. Notably, Nesprin-3 overexpression can rescue the nuclear morphology and proliferative phenotype in pancreatic cancer cells with mKRAS knockdown. Finally, utilizing an Emerin mutant that cannot interact with Nesprin-3 we failed to rescue these nuclear size changes. Our data demonstrate a novel mechanism underlying the oncogenic function of KRAS, a major driver of this dismal condition.
The AP-1-like protein Yap8 is required for arsenic tolerance in the yeast Saccharomyces cerevisiae. Previous work has shown that Yap8 binds to arsenic via critical cysteine residues, which converts Yap8 into an active transcriptional regulator of the arsenic detoxification genes ACR2 and ACR3. However, how Yap8 couples arsenic sensing to gene activation is not fully understood. Here, we provide mechanistic insights into Yap8-dependent gene regulation by identifying cis-regulatory elements and regulatory factors involved. We show that full activation of ACR3 expression requires two Yap8 binding elements in the ACR3 promoter, one accessible and one occluded by a nucleosome. Arsenic stress leads to Yap8-dependent chromatin remodeling which enables Yap8 to bind also to the occluded site. We also demonstrate that Yap8 directly interacts with components of the SWI/SNF chromatin remodeling and SAGA histone acetyl transferase complexes and recruits them to the ACR3 promoter. Accordingly, the cis-regulatory elements and the SAGA and SWI/SNF complexes are all required for arsenic tolerance. Our data is consistent with a model in which arsenic binding to Yap8 results in gene activation and arsenic tolerance via Yap8-dependent recruitment of coactivators and chromatin remodeling factors to the ACR3 promoter.
Valosin-containing protein (VCP) is a crucial ATPase involved in maintaining protein homeostasis through the ubiquitin-proteasome system (UPS) and endoplasmic reticulum-associated degradation (ERAD). Dysregulation of VCP has been implicated in neurodegenerative diseases, cancer, and myopathies, and has also been associated with cardiac dysfunction and hypertrophy remodeling. The roles of VCP in the context of cardiomyocyte function and protein homeostasis are still poorly understood. This study examines the effects of pharmacological Vcp inhibition in zebrafish embryos using CB-5083, a selective Vcp ATPase inhibitor. CB-5083-treated embryos exhibited cardiac and skeletal muscle abnormalities, including myofibrillar disorganization, impaired cardiac function, and locomotor defects, closely resembling CRISPR/Cas9-mediated vcp knockout phenotypes. Early developmental inhibition (24-72 hpf) led to severe cardiac impairment and apoptosis, whereas inhibition during late development (72-120 hpf) induced ventricular hypertrophy with preserved contractile function, suggesting a developmental stage-dependent effect. Furthermore, Vcp inhibition was associated with markers of disrupted proteostasis, suggesting UPS dysfunction and ER stress activation. These findings establish a zebrafish model of VCP-related cardiomyopathy, highlight its role in cardiac proteostasis and hypertrophic remodeling, and provide novel insights into disease mechanisms and potential therapeutic targets.
The fascinating world of long non-coding RNAs (lncRNAs) has expanded significantly over the past two decades, and their characterization has revealed their involvement in a variety of biological processes both in physiological and pathological contexts. Here, we review the crosstalk between lncRNAs and the p53 family of transcription factors in cancer, with particular emphasis on the molecular features that enable cells to become malignant, progress, and metastasize. Finally, we discuss how this knowledge is currently being translated into the clinic, including the use of lncRNAs as biomarkers and therapeutic targets.
Paeonol (Pae) exhibits potent anti-inflammatory and antitumor effects. Chronic atrophic gastritis (CAG) is considered a gastric precancerous lesion, and the JAK2/STAT3 pathway plays a key role in gastrointestinal inflammation and tumorigenesis. Whether Pae ameliorates CAG by regulating this pathway remains unclear. A 1-methyl-3-nitro-1-nitrosoguanidine (MNNG)-induced malignant transformed cell (MC) model and a CAG rat model were established. The malignant biological behaviors of MC cells were assessed using the Cell Counting Kit-8 (CCK-8) assay, clone formation, and Transwell assays. Gastric histopathological changes were examined by pathological staining, inflammatory factors and gastric mucosa-associated factors were detected via enzyme-linked immunosorbent assay (ELISA). Inflammation, proliferation, epithelial-mesenchymal transition (EMT), and the JAK2/STAT3 pathway-related protein expression was analyzed by Western blotting. MC cells exhibited enhanced proliferation, migration, invasion, and EMT, all of which were significantly suppressed by Pae treatment. CAG rats showed severe gastric mucosal damage, intestinal metaplasia, collagen fiber disorganization, and increased Ki-67 expression. Pae treatment alleviated histopathological injury, reduced inflammatory factor levels, and promoted gastric mucosa-associated factor synthesis. Furthermore, Pae markedly inhibited the JAK2/STAT3 pathway in MC cells and gastric tissues. In conclusion, Pae suppresses malignant transformation and alleviates gastric histopathological injury in CAG by modulating the JAK2/STAT3 pathway.
Acute pancreatitis (AP) is a life-threatening condition driven by premature pancreatic enzyme activation, leading to systemic complications and multi-organ dysfunction. Chaihu Shugan Powder (CSP) has been reported to mitigate pancreatic injury associated with AP, but the detailed regulatory mechanism was unclear. In our study, we investigated the fundamental mechanism of how CSP attenuated AP injury. The AP models were constructed by applying cerulein in AR42J cells and rats. Individual CSP interventions did not affect normal cell function. CSP partially reversed cerulein-induced cell damage, as reflected by increased cell viability, the level of glutathione (GSH), and ferroptosis protein markers but decreased the contents of inflammatory factor, reactive oxygen species (ROS), malondialdehyde (MDA), Fe2+ and iron. CSP activated the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α)/nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway, which in turn reduced ferroptosis in cerulein-exposed AR42J cells. Silencing the PGC-1α gene could partially inhibit the activation of the PGC-1α/Nrf2/HO-1 pathway by CSP in cerulein-induced AR42J cells. In AP rats, CSP alleviated AP-related pathomorphological changes and ferroptosis in rats by activating PGC-1α/Nrf2/HO-1 pathway. Altogether, the mechanism by which CSP alleviated AP injury in rats may be correlated with the activation of PGC-1α/Nrf2/HO-1 pathway.
Alternative splicing is a fundamental mechanism that ensures accurate gene expression, supports cellular adaptability, and expands protein diversity beyond the limits of a fixed gene pool. With aging, splicing fidelity weakens, contributing to decline in RNA homeostasis and disrupting essential cellular functions, including mitochondrial oxidative phosphorylation, genome stability, and immune regulation, and in turn accelerating tissue and organ dysfunction. Evidence from senescent cells, aged tissues, and model organisms shows that altered levels of splicing factors and increased RNA polymerase II elongation rates impair co-transcriptional splicing and promote mis-spliced isoforms that reinforce senescence and drive pathology. Dysfunction of RNA-binding proteins further contributes to aberrant splicing, linking splicing defects to age-related diseases such as atherosclerosis, osteoarthritis, sarcopenia, and neurodegenerative disorders like Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Therapeutic strategies to correct splicing defects, such as antisense oligonucleotides, RNA interference, CRISPR-Cas systems, ADAR-mediated editing, and RNA aptamers, can restore a homeostatic balance of mRNA isoforms. However, major challenges remain, including distinguishing adaptive physiological from pathological splicing 'noise' and achieving targeted delivery to tissues. Despite these obstacles, RNA splicing dysregulation represents a promising avenue to extend health span by reestablishing homeostatic RNA programs, and reinforces the idea that "transcriptomic instability" is a hallmark of aging.
Gastrointestinal stromal tumor (GIST), the most common gastrointestinal mesenchymal neoplasm, remains poorly understood at the molecular level, limiting precise diagnosis and targeted therapy. This study aimed to systematically identify key GIST-associated genes through multiomic integration and experimental validation. We analyzed three GIST transcriptomic datasets from GEO, corrected batch effects via surrogate variable analysis (SVA), and identified 61 differentially expressed genes (DEGs) using limma. Weighted gene co-expression network analysis (WGCNA) highlighted progression-related modules, which were refined using random forests and LASSO regression to prioritize C3 and complement factor D (CFD), both of which showed robust diagnostic performance (AUC: 0.928 for C3; 0.955 for CFD). Experimental validation confirmed C3/CFD downregulation in GIST tissues, correlating with advanced stage and poor survival. Functional assays demonstrated their tumor-suppressive roles, inhibiting GIST cell proliferation, colony formation, and migration. CIBERSORT analysis linked C3/CFD to altered immune infiltration, while ssGSEA/GSEA implicated their involvement in lipid metabolism and oxidative phosphorylation. These findings establish C3 and CFD as critical tumor-suppressive biomarkers that modulate the immune response and reprogram metabolism, offering new avenues for GIST diagnosis and therapy.
Cancer develops from the unregulated proliferation of cells, influenced by a confluence of genetic mutations and epigenetic modifications that disrupt normal regulatory networks. In recent years, cellular metabolism has emerged as an important factor in controlling epigenetic states by connecting the availability of intracellular metabolites to changes in chromatin. One such metabolite is lactate, a glycolytic by-product produced in large amounts in tumor cells because of the Warburg effect. Lactate has been found to be a substrate for histone lactylation, a recently discovered epigenetic mark that affects gene expression. Although histone lactylation is gaining importance in cancer biology, its functional role in breast cancer remains inadequately elucidated. In this study, we utilized a lactate-deficient cell line created by the knockout of PKM2 to examine the effects of promoter-level histone H3 lysine 18 lactylation (H3K18la) on the regulation of the DNMT3A gene, which subsequently influences SMAD2 expression and modulates the TGF-β signaling pathway and cellular proliferation in breast cancer. Our findings elucidate a novel metabolic-epigenetic axis that cancer cells utilize to drive tumorigenesis.
