HIF-1α pathway: role, regulation and intervention for cancer therapy

Unveiling EIF5A2: A multifaceted player in cellular regulation, tumorigenesis and drug resistance

The eukaryotic initiation factor 5A2 gene (EIF5A2) is a highly conserved and multifunctional gene that significantly influences various cellular processes, including translation elongation, RNA binding, ribosome binding, protein binding and post-translational modifications. Overexpression of EIF5A2 is frequently observed in multiple cancers, where it functions as an oncoprotein. Additionally, EIF5A2 is implicated in drug resistance through the regulation of various molecular pathways. In the review, we describe the structure and functions of EIF5A2 in normal cells and its role in tumorigenesis. We also elucidate the molecular mechanisms associated with EIF5A2 in the context of tumorigenesis and drug resistance. We propose that the biological roles of EIF5A2 in regulating diverse cellular processes and tumorigenesis are clinically significant and warrant further investigation.

Effect of Hypoxia on the Mucus System and Intragastric Microecology in the Gastrointestinal Tract

Digestive diseases have a high incidence worldwide, with various geographic, age, and gender factors influencing the occurrence and development of the diseases. The main etiologic factors involve genetics, environment, lifestyle, and dietary habits. In a low-oxygen environment, however, the body's tissue cells activate hypoxia-inducible factor (HIF), which produces different inflammatory mediators. Hypoxia impacts health at the molecular level by modulating cellular stress responses, metabolic pathways, and immune functions. It also alters gene expression and cellular behavior, thereby affecting gastrointestinal function. Under normal physiological conditions, the gastrointestinal mucus system serves as a crucial protective barrier, defending against mechanical injury, pathogenic invasion, and exposure to harmful chemicals. The integrity and functionality of this barrier are dependent on the synthesis and regulation of mucins and mucus, which are influenced by multiple factors. Additionally, the composition and diversity of the gastric microbiota are shaped by factors such as Helicobacter pylori infection, diet, and lifestyle. A balanced gastric microbiota supports gastrointestinal health and fortifies the mucus barrier. However, hypoxia can disrupt this equilibrium, leading to inflammation, alterations in the mucus layer, and destabilization of the gastric microbiota. Understanding the interplay between hypoxia, the mucus system, and the gastric microbiota is essential for identifying novel therapeutic strategies. Future research should elucidate the mechanisms through which hypoxia influences these systems and develop interventions to mitigate its adverse effects on gastrointestinal health. We examined the impact of hypoxia on the gastrointestinal mucus system and gastric microbiota, highlighting its implications for human health and potential therapeutic approaches.

Chronic Mountain Sickness: A Comprehensive Review of Current Management and Proposals for Novel Therapies

Chronic mountain sickness (CMS) is an acquired condition affecting 5%-10% of high-altitude residents. Lifelong exposure to chronic hypoxia triggers excessive erythrocytosis, resulting in an expanded hematocrit. Patients present with symptoms such as dyspnea, fatigue, and palpitations. Complications such as pulmonary hypertension and heart failure are often fatal. Relocation to sea level remains the only definitive management of CMS but poses an unacceptable personal burden. Long-term oxygen therapy provides symptomatic relief, but dependency issues remain a concern. Phlebotomy reduces hematocrit and offers short-term symptom relief. However, side effects and cultural conflicts continue to pose challenges. Acetazolamide, enalapril, and medroxyprogesterone have lowered hematocrit and alleviated symptoms in human trials. Further research into systemic side effects, application in women, and long-term use is required. Methylxanthines, adrenergic blockers, almitrine, and dopamine antagonists showed promise in murine and/or short-term human trials, highlighting the need for further long-term human trials. Inhibition of hypoxia-inducible factor and Janus Kinase-signal transducer and activator of transcription pathways is currently used to suppress hematocrit in polycythemia vera, demonstrating potential application in CMS. Topiramate may stimulate ventilation via acid-base modulation, thus providing therapeutic value. Similarly, the effect of aspirin and caffeine on ventilation may provide a low-cost, accessible intervention.

The Distinct Role of HIF-1α and HIF-2α in Hypoxia and Angiogenesis

Hypoxia results in a wide range of adaptive physiological responses, including metabolic reprogramming, erythropoiesis, and angiogenesis. The response to hypoxia at the cellular level is mainly regulated by hypoxia-inducible factors (HIFs): HIF1α and HIF2α isoforms. Although structurally similar and overlapping gene targets, both isoforms can exhibit distinct expression patterns and functions in some conditions of hypoxia. The interaction between these isoforms, known as the "HIF switch", determines their coordinated function under varying oxygen levels and exposure time. In angiogenesis, HIF-1α is rapidly stabilized under acute hypoxia, prompting a metabolic shift from oxidative phosphorylation to glycolysis and initiating angiogenesis by activating endothelial cells and extracellular matrix remodeling. Conversely, HIF-2α regulates cell responses to chronic hypoxia by sustaining genes critical for vascular remodeling and maturation. The current review highlights the different roles and regulatory mechanisms of HIF-1α and HIF-2α isoforms, focusing on their involvement in cell metabolism and the multi-step process of angiogenesis. Tuning the specific targeting of HIF isoforms and finding the right therapeutic window is essential to obtaining the best therapeutic effect in diseases such as cancer and vascular ischemic diseases.

Single-cell RNA sequencing highlights the role of proinflammatory fibroblasts, vascular endothelial cells, and immune cells in the keloid immune microenvironment

BACKGROUND

Keloids, characterized by an aberrant wound-healing process and a highly complex immune microenvironment, pose significant challenges for clinical management. Fibroblasts and vascular endothelial cells (VEC) were identified as the leading cells of keloid development. However, their roles in the keloid immune landscape have yet to be thoroughly elucidated.

METHODS

To explore the functional state of cells in the immune landscape of keloids, we conducted a single-cell RNA sequencing analysis on the tissue from three keloid lesions and two specimens of healthy skin. We simultaneously utilized available keloid data from the public database for external validation.

RESULTS

Specific subsets, such as proinflammatory fibroblasts (piF) and VEC, were markedly elevated in lesional skin compared to normal skin. Subsequent differential gene expression and Gene Ontology analyses indicated that these subsets may be involved in shaping the microenvironment. In keloids, there is an increased expression of immune-associated genes (P < 0.05), including TNFRSF6B, HGF, and TGFB3, alongside a decreased expression of inflammatory chemokines in the piF. Moreover, the significant upregulation of immune suppressive genes (P < 0.05), including CD39, CD73, and HIF1A, suggested the potential involvement of VEC as a conditional immune subpopulation in the keloid microenvironment. Immune cell communication analysis revealed preferential enrichment of macrophages and Tregs, highlighting intensified macrophage-centered interactions within the keloid microenvironment.

CONCLUSION

Our study highlighted the role of piF and VEC in the immune microenvironment of keloids for the first time, providing potential targets for therapeutic development.

Cd stabilizes HIF-1α under normoxic conditions via lysine-63-linked ubiquitination and induces ER stress and cell proliferation

Cadmium, a carcinogenic and toxic substance released into the environment, has emerged as a potent activator of lysine-63 ubiquitination, and lysine-63 is a crucial regulator of signal transduction pathways. Although critical, very little information is currently available about how the activation of lysine 63 ubiquitination by Cd might contribute to cancers and inflammatory diseases. The present study provides the first evidence that Cd stabilizes hypoxia-inducible factor-1-alpha, a transcription factor, under normoxic conditions via lysine 63 ubiquitination. Cd induces the accumulation of lysine 63 polyubiquitinated proteins. Importantly, Cd-induced ubiquitination does not prevent oxidative damage or proteasome impairment. Instead, we demonstrated that Cd activates lysine 63 ubiquitination and amplifies its accumulation by overloading the capacity of the autophagy pathway, thus promoting endoplasmic reticulum stress and cell death. At the molecular level, Cd-induced lysine 63 polyubiquitination is correlated with the stabilization of hypoxia-inducible factor-1-alpha, which translocates into the nucleus and promotes the expression of oncogenes such as interleukin 8 and vascular endothelial growth factor. Strikingly, prolonged cell exposure to high Cd concentrations induces increased lysine-63 polyubiquitination, which promotes aggresome formation, thus preventing this protein from interacting with its downstream nuclear targets. Our results showed that Cd is an activator of K63-linked ubiquitination that stabilizes and promotes the accumulation of HIF-1α, which blocks autophagy, thus resulting in endoplasmic reticulum stress. In addition, a small amount of HIF-1α was observed in the nucleus. We therefore propose that the aberrant activation of lysine 63 polyubiquitination by the carcinogen Cd could promote cell proliferation and inflammation at low levels, while high levels lead to cell death.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-024-00266-9.

Evaluation of hypoxia-inducible factor-1 and 2 alpha inhibitory compounds in the oral cavity and pharyngeal cancer

Hypoxia in the tumor environment leads to an activation of genotypes that favors the tumor, promoting angiogenesis, epithelial-mesenchymal transition, cell invasion, and metastasis. It is considered a prognostic factor related to the progression and aggressiveness of Head and Neck Cancer (HNC). Hypoxia-inducible factor (HIF) is the main gene activated by hypoxia and has been associated with tumor advancement. Thus, this work aims to evaluate the performance of the compounds Acriflavine, Resveratrol, Topotecan, and RNA interference (siRNA) as HIF inhibitors as well as a therapeutic approach. Molecular docking results have suggested that the evaluated compounds present potential interactions with HIF-1α and HIF-2α. In vitro analysis, they demonstrated that treatments with Acriflavine and Topotecan caused a decrease in the gene expression of HIFs in the HN13 cell line (carcinoma of the oral cavity). Furthermore, treatments performed with siRNAs effectively inhibited gene expression of HIFs in HN13 and FaDu (carcinoma of the pharynx) cell lines. Considering the role of hypoxia and HIFs in tumor aggressiveness; the present study shows the potential of the evaluated compounds as a therapeutic use for the prevention of tumor progression in head and neck cancer.

Isorhapontigenin Inhibits Cell Growth, Angiogenesis, Migration, and Invasion of Non-Small-Cell Lung Cancer Cells Through NEDD9 Signaling

Lung cancer is the leading cause of cancer deaths among American men, even though various treatments are available. The discovery and use of new alternative drugs to treat lung cancers are needed to reduce lung cancer mortality. Phytochemicals are potentially desirable therapeutic agents due to their better safety profiles. Isorhapontigenin (ISO) is an orally bioavailable dietary stilbene. Our studies show that treatment with ISO inhibits human lung cancer cell growth, angiogenesis, invasion, and migration. Neural precursor cell expressed developmentally downregulated 9 (NEDD9), a multi-domain scaffolding protein, regulates various processes crucial for tumorigenesis and metastasis. Our results show that NEDD9 is upregulated in the lung tissues from human lung adenocarcinomas (LUADs) and squamous-cell carcinomas (LUSCs) compared to normal lungs. Overexpression of NEDD9 elevates the invasion and migration of human lung cancer cells. Treatment of human lung cancer cells with ISO decreases NEDD9 protein levels. Our studies have also demonstrated that NEDD9 positively regulates angiogenesis, an essential factor in cancer progression. ISO treatment reduces angiogenesis. Moreover, ISO reduces the protein levels of hypoxia-inducible factor-1α (HIF-1α), a transcription factor critical for angiogenesis. Aberrant high expression of β-Catenin leads to various diseases including cancer. Our results show that ISO treatment reduces the activation of β-Catenin through the downregulation of NEDD9. Studies indicate that ISO decreases NEDD9, causing the suppression of cell growth, angiogenesis, invasion, and migration of human lung cancer cells. ISO is a potent therapeutic agent for lung cancer treatment.

Deciphering the Role of Innate Lymphoid Cells Group 3 in the Gut Microenvironment: A Narrative Review of Their Novel Contributions to Autoimmune Disease Pathogenesis

Type 3 Innate lymphoid cells (ILC3s) play a crucial role in intestinal immune function by serving as an innate effector that contributes to early-life defense against pathogens and helps protect the intestines from bacterial infections. ILC3s exert their immune function through cytokine secretion, patrolling actions and the generation of memory ILC3s that aid in repairing epithelial tissue and preserving mucosal barrier integrity. Moreover, dysregulation of ILC3s function has been implicated in the pathogenesis and progression of autoimmune diseases. This comprehensive review aims to explore the interactions between gut microbes, gut microbial metabolites, and diet in relation to ILC3s within the context of the gut microenvironment. Furthermore, the gut microenvironment has the potential to influence distant extra-intestinal sites through immunomodulation, thereby modifying their risk of inflammation. The gut has emerged as a significant focus of autoimmune disease research in recent years. However, the relationship between gut ILC3s and autoimmune diseases remains poorly understood. This paper aims to examine the potential association between ILC3s and autoimmune diseases.

Modulation of renal fibrosis-related signaling pathways by traditional Chinese medicine: molecular mechanisms and experimental evidence

Renal fibrosis (RF), characterized by excessive deposition of extracellular matrix leading to tissue damage and scar formation, represents a refractory disease and a pivotal pathological basis for the progression to end-stage renal disease. The pathogenesis of RF is intricate, prominently implicating multiple key signaling pathways, including adenosine monophosphate-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR), phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), transforming growth factor-β1/small mother against decapentaplegic (TGF-β1/Smad), toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB), wingless integrated/β-catenin (Wnt/β-catenin), hypoxia-inducible factor-1α (HIF-1α), Hedgehog, and mitogen-activated protein kinase (MAPK). The current Western medical practices primarily rely on supportive and replacement therapies, which are often costly and suboptimal in efficacy. In contrast, traditional Chinese medicine (TCM), with its inherent advantages of multi-target, multi-pathway, and multi-effect modulation, emerges as a promising new strategy for RF treatment. However, a systematic, comprehensive, and detailed summary of these advancements remains absent. Therefore, this review consolidates the recent research progress on TCM modulation of RF-related signaling pathways, aiming to provide a theoretical foundation for further investigations into RF and the development of TCM interventions.

Exosome-based immunotherapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a significant global health concern and ranks as the third leading cause of cancer-associated mortality. Systemic therapy faces the emergence of resistance, which hinders the clinical benefits. Recent evidence suggests that exosomes, measuring between 30 and 150 nm in size, which impact the antitumor immune responses, making them a promising candidate for cancer immunotherapy. Owing to their unique physical and chemical characteristics, exosomes can be tailored and engineered for a range of therapeutic objectives. In the present review, we outline the immunomodulatory functions of exosomes in the tumor microenvironment (TME) of HCC, aiming to decipher the underlying mechanisms of exosomes in remodeling suppressive TME. Moreover, we provide detailed and intuitive resource for leveraging the potential of exosomes in immunotherapy, presenting valuable strategies to improve and optimize HCC treatment. Despite the huge therapeutic potential of exosomes, significant challenges persist, including the need for standardization in exosome production, optimization of cargo loading techniques, and the assurance of safety and effectiveness in clinical applications. Addressing these challenges may pave the way for exosome-based immunotherapy for HCC patients.

Decoding tumor angiogenesis: pathways, mechanisms, and future directions in anti-cancer strategies

Angiogenesis, a crucial process in tumor growth and metastasis, necessitates targeted therapeutic intervention. This review reviews the latest knowledge of anti-angiogenesis targets in tumors, with emphasis on the molecular mechanisms and signaling pathways that regulate this process. We emphasize the tumor microenvironment's role in angiogenesis, examine endothelial cell metabolic changes, and evaluated potential therapeutic strategies targeting the tumor vascular system. At the same time, we analyzed the signaling pathway and molecular mechanism of tumor angiogenesis in detail. In addition, this paper also looks at the development trend of tumor anti-angiogenesis drugs, including their future development direction and challenges, aiming to provide prospective insight into the development of this field. Despite their potential, anti-angiogenic therapies encounter challenges like drug resistance and side effects, necessitating ongoing research to enhance cancer treatment strategies and the efficacy of these therapies.

Predator-Prey Model for Simulating the Genetic Carcinogenicity of Aggressive Toxicant-Related Cancer

The mechanism of how toxicant exposure leads to aggressive tumors remains unresolved. A genetic-based hypothesis predicts that under stress, the transcription of growth-related genes will be inhibited by the activation of mitogenic pathways, redirecting energy toward stress response and increasing survival. This hypothesis fails to explain why epidemiological data suggest that growth and stress response are activated, as patients exposed to toxicants exhibit more aggressive growth than nonexposed individuals. This co-occurrence requires increased energy availability to prevent the activation of mitogenic pathways, as seen in the Warburg effect. We hypothesize that if pollutant effects cease, it might drive aggressive cancer, as excess energy that is no longer used for stress response can fuel rapid growth. We model this allocation between growth and stress response as a trophic competition using the Lotka-Volterra equations and using as input RNA-Seq data from growth- and stress-related genes obtained from cancer cells exposed to copper, cadmium, and carboplatin. Our findings suggest that the energy allocation to growth and its rate of allocation is higher in exposed than nonexposed tumors and results in overgrowth in unexposed cells. This study helps to understand how certain scenarios, such as partial or total cessation of exposure, in toxicant-related cancer can drive cancer aggressiveness.

Ubiquitination of transcription factors in cancer: unveiling therapeutic potential

Transcription factors, pivotal in gene expression regulation, are essential in cancer progression. Their function is meticulously regulated by post-translational modifications, including ubiquitination. This process, which marks proteins for degradation, can either enhance or inhibit the function of transcription factors, contingent on the context. In cancers, dysregulated ubiquitination of transcription factors contributes to the hallmark of uncontrolled growth and survival of tumors. For example, tumor suppressors such as p53 might be degraded prematurely due to abnormal ubiquitination, causing genomic instability. On the other hand, oncogenic transcription factors may gain stability via ubiquitination, thus facilitating tumorigenesis. Targeting the ubiquitin-proteasome system (UPS) therefore could be a viable therapeutic approach in cancer. Emerging treatments aim to block the ubiquitination of oncogenic transcription factors or to stabilize tumor suppressors. This review underscores the critical impact of transcription factor-altered ubiquitination on cancer progression. Additionally, it outlines innovative therapeutic approaches that involve inhibitors or drugs directed at specific ubiquitin E3 ligases and deubiquitinases (DUBs) that regulate transcription factor activity.

Small extracellular vesicles (sEVs) in pancreatic cancer progression and diagnosis

Pancreatic cancer is one of the most aggressive malignancies with poor prognostic outcomes, necessitating the exploration of novel biomarkers and therapeutic targets for early detection and effective treatment. Small extracellular vesicles (sEVs) secreted by cells, have gained considerable attention in cancer research due to their role in intercellular communication and their potential as non-invasive biomarkers. This review focuses on the role of sEVs in the progression of pancreatic cancer and their application as biomarkers. We delve into the biogenesis, composition, and functional implications of sEVs in pancreatic tumor biology, emphasizing their involvement in processes such as tumor growth, metastasis, immune modulation, and chemotherapy resistance. In addition, we discuss the challenges in isolating and characterizing sEVs. The review also highlights recent advances in the utilization of sEV-derived biomarkers for the early diagnosis, prognosis, and monitoring of pancreatic cancer. By synthesizing the latest findings, we aim to underscore the significance of sEVs in pancreatic cancer and their potential to revolutionize patient management through improved diagnostics and targeted therapies.

Unraveling the role of hypoxia-inducible factors in cutaneous melanoma: from mechanisms to therapeutic opportunities

Hypoxia is a common feature of solid malignancies, including cutaneous melanoma (CM). Hypoxia-inducible factor (HIF)-1α and HIF-2α orchestrate cellular responses to hypoxia and coordinate a transcriptional program that promote several aggressive features in CM, such as angiogenesis, epithelial-mesenchymal transition, metastasis formation, metabolic rewiring, and immune escape. BRAFV600E, which is the most frequent mutation observed in CM patients, usually increases HIF-α signaling not only in hypoxia, but also in normoxic CM cells, enabling HIF-1α and HIF-2α to continuously activate downstream molecular pathways. In this review, we aim to provide a comprehensive overview of the intricate role and regulation of HIF-1α and HIF-2α in CM, with a brief focus on the complex interactions between HIF-α subunits and non-coding RNAs. We also discuss HIF-α-mediated cellular responses in normoxia along with the mechanisms that allow HIF-α subunits to maintain their stability under normal oxygen conditions. Finally, we resume available evidence on potential therapeutic approaches aimed at targeting HIF-1α and/or HIF-2α.

dFLASH; dual FLuorescent transcription factor activity sensor for histone integrated live-cell reporting and high-content screening

Live-cell transcription factor (TF) activity reporting is crucial for synthetic biology, drug discovery and functional genomics. Here we present dFLASH (dual FLuorescent transcription factor Activity Sensor for Histone-integrated live-cell reporting), a modular, genome-integrated TF sensor. dFLASH homogeneously and specifically detects endogenous Hypoxia Inducible Factor (HIF) and Progesterone Receptor (PGR) activities, as well as coactivator recruitment to synthetic TFs. The dFLASH system produces dual-color nuclear fluorescence, enabling normalized, dynamic, live-cell TF activity sensing with strong signal-to-noise ratios and robust screening performance (Z' = 0.61-0.74). We validate dFLASH for functional genomics and drug screening, demonstrating HIF regulation via CRISPRoff and application to whole-genome CRISPR KO screening. Additionally, we apply dFLASH for drug discovery, identifying HIF pathway modulators from a 1600-compound natural product library using high-content imaging. Together, this versatile platform provides a powerful tool for studying TF activity across diverse applications.

Mechanisms of HDACs in cancer development

Histone deacetylases (HDACs) are a class of epigenetic regulators that play pivotal roles in key biological processes such as cell proliferation, differentiation, metabolism, and immune regulation. Based on this, HDAC inhibitors (HDACis), as novel epigenetic-targeted therapeutic agents, have demonstrated significant antitumor potential by inducing cell cycle arrest, activating apoptosis, and modulating the immune microenvironment. Current research is focused on developing highly selective HDAC isoform inhibitors and combination therapy strategies tailored to molecular subtypes, aiming to overcome off-target effects and resistance issues associated with traditional broad-spectrum inhibitors. This review systematically elaborates on the multidimensional regulatory networks of HDACs in tumor malignancy and assesses the clinical translation progress of next-generation HDACis and their prospects in precision medicine, providing a theoretical framework and strategic reference for the development of epigenetic-targeted antitumor drugs.

Elucidating the Molecular Mechanisms of Hederagenin-Regulated Mitophagy in Cervical Cancer SiHa Cells through an Integrative Approach Combining Proteomics and Advanced Network Association Algorithm

Hederagenin (Hed), a natural triterpenoid, exhibits antitumor potential in cervical cancer. The present study was designed to explore Hed's regulatory mechanisms on mitophagy in SiHa cervical cancer cells, employing tandem mass tag (TMT) proteomics and an advanced network association algorithm (NAA). Our findings revealed that Hed decreased SiHa cell viability, induced apoptosis, and altered mitochondrial membrane potential. Notably, Hed inhibited mitophagic flux under both normoxic and hypoxic conditions. Through TMT proteomics analysis and innovative NAA, we identified a close association between the HIF-1 signaling pathway and mitophagy. Network analysis further suggested that Hed acts on a target network centered on SRC, STAT3, AKT1, and HIF1A. Western blot analysis confirmed the expression and phosphorylation status of these targets in response to Hed. This study elucidates the molecular mechanisms underlying Hed's regulation of mitophagy in SiHa cells, offering novel insights and potential therapeutic targets for cervical cancer treatment.

The role and mechanism of aerobic glycolysis in nasopharyngeal carcinoma

This review delves into the pivotal role and intricate mechanisms of aerobic glycolysis in nasopharyngeal carcinoma (NPC). NPC, a malignancy originating from the nasopharyngeal epithelium, displays distinct geographical and clinical features. The article emphasizes the significance of aerobic glycolysis, a pivotal metabolic alteration in cancer cells, in NPC progression. Key enzymes such as hexokinase 2, lactate dehydrogenase A, phosphofructokinase 1, and pyruvate kinase M2 are discussed for their regulatory functions in NPC glycolysis through signaling pathways like PI3K/Akt and mTOR. Further, the article explores how oncogenic signaling pathways and transcription factors like c-Myc and HIF-1α modulate aerobic glycolysis, thereby affecting NPC's proliferation, invasion, metastasis, angiogenesis, and immune evasion. By elucidating these mechanisms, the review aims to advance research and clinical practice in NPC, informing the development of targeted therapeutic strategies that enhance treatment precision and reduce side effects. Overall, this review offers a broad understanding of the multifaceted role of aerobic glycolysis in NPC and its potential impact on therapeutic outcomes.

Age-Related Macular Degeneration Pathophysiology and Therapeutic Potential of Tocotrienols: An Update

Age-related macular degeneration (AMD) poses a significant threat to visual health among the elderly, necessitating urgent preventive measures as the global population ages. Extensive research has implicated oxidative stress (OS)-induced retinal damage as a primary contributor to AMD pathogenesis, prompting investigations into potential therapeutic interventions. Among the various nutrients studied for their potential in AMD risk reduction, antioxidants have shown promise, with initial findings from the Age-Related Eye Disease Study suggesting a correlation between antioxidant supplementation and decreased AMD progression. This article explores the scientific foundation supporting the therapeutic efficacy of tocotrienol-rich fraction (TRF) as a viable candidate for slowing AMD progression, based on interventional studies. AMD is characterized by OS, inflammation, dysregulated lipid metabolism, and angiogenesis, all of which TRF purportedly addresses through its potent anti-inflammatory, lipid-lowering, antiangiogenic, and antioxidant properties. The review underscores TRF's promising attributes, aiming to deepen understanding of AMD pathogenesis and advocate for TRF-based pharmacological interventions to enhance therapeutic outcomes. Given the pressing need for effective AMD treatments, TRF represents a promising avenue for intervention, offering hope for improved vision outcomes and enhanced quality of life for individuals affected by this debilitating condition.

Cell-type dependent effect of 3D collagen matrix on cancer cell resistance to suboptimal conditions: the case of serum deprivation, glucose starvation, and hypoxia

The extracellular matrix (ECM) and its primary chemical components, including collagen, play a pivotal role in carcinogenesis and tumor progression. The ECM actively regulates cell proliferation, migration, and, importantly, resistance to various adverse factors. It is widely recognized as a key factor in modifying the resistance of tumor cells to various treatment modalities and cytotoxic compounds. However, the role of the ECM in tumor cell adaptation to nutritional deficiencies and hypoxic conditions remains significantly less studied. Since it is generally accepted that tumor cells resistance increases when cultured in a three-dimensional matrix, we sought to experimentally test the universality of this statement. In this work, we analyzed the responses of tumor cells with varying origins and proliferative activities, including human bladder carcinoma, epidermoid carcinoma, and ovarian carcinoma, to deprivation of serum, glucose and oxygen. We compared cell resistance to suboptimal conditions when cultured in a monolayer on tissue culture (TC)-treated polystyrene, on collagen-coated surfaces, or within a three-dimensional hydrogel composed of collagen type I. All three cell lines were stably transfected with fluorescent protein genes. To register the cell growth dynamics, we used a fluorescence-based technique that allows long-term quantitative observations without disrupting the hydrogel. The analyzed cell lines demonstrated different patterns of relative sensitivity to suboptimal conditions. We revealed that the direction and intensity of the collagen matrix effect depend on the cell type. Slowly proliferating ovarian carcinoma cells showed no noticeable changes in their behavior when cultured in a gel compared to a monolayer. In the case of bladder carcinoma, we registered predominantly resistance-stimulating effect of the collagen matrix, but it was significant only under serum deprivation. The most pronounced effect of collagen was registered for epidermoid carcinoma. Importantly, this effect was ambivalent: gel-embedded cells demonstrated significantly enhanced resistance to serum deprivation, but, at the same time, they were more responsive to glucose starvation and hypoxic conditions. We attribute the registered phenomenon to the individual characteristics of tumor cells with different origins and metabolic activities.

Calpain 2 Isoform-Specific Cleavage of Filamin A Enhances HIF1α Nuclear Translocation, Promoting Metastasis in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) remains a challenge due to its aggressive nature and limited therapeutic options. Calpain 2, a member of the calcium-dependent cysteine protease family, is particularly associated with poor prognosis in TNBC. This study explores the isoform-specific role of calpain 2 in TNBC, examining its correlation with prognosis and its mechanistic impact on metastasis. Bioinformatic analyses, including Kaplan-Meier survival plots, univariate Cox proportional analysis, and gene set enrichment analysis (GSEA), assessed CAPN2 expression and its association with mesenchymal genes in TNBC. Results of cell-based experiments with CAPN2 knockdown or overexpression indicate that elevated CAPN2 expression correlates with poor clinical outcomes and enhanced metastatic potential in TNBC. CAPN2 knockdown inhibited the epithelial-mesenchymal transition (EMT), reducing cancer cell proliferation, migration, and invasion. Calpain 2 downregulation reversed the EMT by reducing isoform-specific cleavage of filamin A, HIF1α nuclear localization and TWIST1 transcription. CNa 29, a calpain 2-specific inhibitor, reduced cancer cell proliferation, decreased filamin A cleavage, downregulated TWIST1 expression, and significantly retarded metastasis,. In conclusion, calpain 2 plays a critical role in TNBC progression by modulating HIF1α and TWIST1, to promote the EMT and metastasis. Isoform-selective inhibition of calpain 2 with CNa 29 presents a promising therapeutic strategy for managing TNBC.

Hypoxia-Inducible Factor 1-Alpha Gene Polymorphisms Impact Risk of Severespectrum Hypertensive Disorders of Pregnancy: A Case-Control Study

Hypoxia-inducible factor 1-alpha (HIF-1α) regulates cellular responses to hypoxia. Overexpression of HIF-1α is associated with abnormal placental trophoblast invasion and hypertensive disorders of pregnancy. We evaluated the putative association between polymorphisms and haplotypes in parental and child HIF-1α genes and the risk of severe-spectrum hypertensive disorders of pregnancy. Case (N = 179) and control (N = 34) mother-father-child triads were recruited by an internet-based method. Cases were defined as HELLP (Hemolysis, Elevated Liver enzymes and Low Platelets) syndrome or pre-eclampsia with severe features. Four HIF-1α single nucleotide polymorphisms were genotyped: rs4902080, rs2057492, rs11549465, rs10144958. Relative risks and 95% confidence intervals were estimated using log-linear free response models, adjusting for correlation between familial genotypes. Relative risk of severe-spectrum hypertensive disorder of pregnancy was increased with double-dose carriage of the T allele for SNP rs4902080 in both mother [RR 6.96, p = 0.028] and child [RR 5.77, p = 0.031]. Child double-dose of the T allele for SNP rs10144958 [RR 5.52, p = 0.047] also increased risk. The heterozygous genotype (CT) for SNPs rs2057482 and rs11549465 was protective against hypertensive disorders of pregnancy when carried by mother [rs2057482: RR 0.34, p < 0.001; rs11549465: RR 0.23, p < 0.001] or child [rs2057482: RR 0.44, p < 0.001; rs11549465: RR 0.31, p < 0.001]. A single copy of the C-c-c-G haplotype (rs4902080-rs2057482-rs11549465-rs10144958, N = 147), conferred decreased risk versus the C-T-T-G haplotype in mother [RR 0.28, p < 0.001] and child [RR 0.36, p < 0.001]. No parent-of-origin effects were seen. We conclude that polymorphism changes and haplotypes in the HIF-1α gene of mothers, fathers, and children are associated with risk for severe-spectrum hypertensive disorders of pregnancy.

Biological pathways and mechanisms linking COPD and cardiovascular disease

Cardiovascular disease (CVD) still poses a significant risk for morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). For a long time, among functional parameters, only the forced expiratory volume in 1 s (FEV1) has been considered as predictive of cardiovascular (CV) mortality especially in elderly patients in fact, there is evidence that reductions in lung function indices can increase the risk of ischaemic heart diseases and cerebrovascular diseases, independently from other risk factors. Now, there is considerable evidence suggesting that hypoxemia, systemic inflammation, oxidative stress and hyperinflation may lead to an early sub-clinical CV involvement in patients affected by COPD. Ageing in itself impacts specific aspects of the CV system, including reduced beta-adrenergic responsiveness, increased vagal tone and myocardial and vascular stiffness, endothelial dysfunction, diminished arterial baroreflex and compromised diastolic function. The complex involved interactions include ageing mechanisms as well as multiple known and unknown (e.g. genetic) risk factors. CVDs are leading causes of mortality in individuals with impaired lung function and the two entities commonly coexist with poor outcomes in patients experiencing both conditions. However, the precise mechanisms responsible for this association remain largely unknown. In this narrative review, we summarize current knowledge regarding the co-occurrence of COPD and CVD focusing on the shared biological pathways and biological mechanisms involved in these conditions.

Nidogen-1 suppresses cell proliferation, migration, and glycolysis via integrin β1-mediated HIF-1α downregulation in triple-negative breast cancer

Nidogen-1 (NID1) is a secreted glycoprotein widely distributed in basement membranes. NID1 interacts with extracellular matrix proteins such as collagen and laminin and has been implicated in the progression of various cancers. However, study on the role of NID1 in breast cancer is scarce and inconsistent. In this work, we found that the expression of NID1 is significantly lower in breast cancer tissue than in normal tissue. In addition, NID1 expression correlated negatively with a poor prognosis for breast cancer patients. Based on those findings, we speculated that NID1 might act as a cancer suppressor in breast cancer. To investigate the role of NID1 in breast cancer, we constructed NID1-overexpressing cell lines. NID1 overexpression decreased breast cancer cell proliferation, migration, and in vivo tumor growth. Moreover, glucose metabolism, which is known to enhance cancer cell proliferation and migration, was also decreased by NID1 overexpression. Mechanistically, NID1 overexpression downregulated hypoxia-inducible factor-1α (HIF-1α) expression at the transcription level. Furthermore, we found that NID1 reduced integrin β1 stability and downregulated the transcription of HIF-1α through the FAK/Src/NF-κB p65 signaling axis, which is downstream of integrin β1. Together, the results of this study demonstrate the tumor suppressive role of NID1 in triple-negative breast cancer.

A Single H2S-Releasing Nanozyme for Comprehensive Diabetic Wound Healing through Multistep Intervention

Diabetic wound healing presents a significant medical challenge and requires multistep interventions due to comprehensive wound environments, such as hyperglycemia, bacterial infection, and impaired angiogenesis. However, current multistep interventions are complicated and need on-demand sequential release and synergy of multicomponents. Herein, a H2S-releasing cascade nanozyme (FeS@Au), which is composed of ultrasmall gold nanocluster (AuNC) loaded on ferrous sulfide nanoparticle (FeSNP), is developed as a single component to regulate glucose level, eliminate infection, and promote angiogenesis, achieving multistep interventions for comprehensive diabetic wound treatment. The glucose oxidase-like activity of AuNC catalyzes glucose into gluconic acid and H2O2, which not only lowers the local glucose level but also decreases the local pH and increases H2O2 level to boost the peroxidase-like activity of FeSNP to generate abundant hydroxyl radical (reactive oxygen species, ROS), inducing ferroptosis-like death in drug-resistant bacteria. Additionally, FeSNP release H2S in the acidified environment to upregulate hypoxia-inducible factor-1 to enhance vascularization through upregulating the expression of vascular endothelial growth factor (VEGF) and other angiogenesis-related genes, reducing the damage to endothelial cells caused by excessive ROS produced by the nanozyme. In a full-thickness MRSA-infected diabetic rat model, FeS@Au significantly eliminates bacteria, enhances angiogenesis, promotes collagen deposition, and accelerates wound healing. This work presents a single nanozyme with H2S-release for multistep interventions, providing a versatile strategy for healing extensive tissue damage caused by diabetes.

Identification and Characterization of Oxidative Stress and Endoplasmic Reticulum Stress-Related Genes in Esophageal Cancer

Increasing evidence highlights the critical roles of oxidative stress and endoplasmic reticulum (ER) stress in tumor initiation and progression. However, the specific functions of related genes in esophageal cancer (ESCA) remain poorly understood. To investigate the impact of oxidative and ER stress on ESCA, this study analyzed the TCGA and GEO databases to identify 12 oxidative stress- and ER stress-related differentially expressed genes (OERDEGs). Pathway analysis revealed significant enrichment in critical processes such as PRC2-mediated methylation, oxidative stress-induced senescence, and NOTCH signaling. A novel LASSO regression model was developed to link gene expression with clinical prognosis, and the model was validated through ROC and Cox regression analyses. Four OERDEGs (CDKN3, PINK1, SPP1, and TFRC) were identified as key biomarkers for ESCA prognosis. Notably, TFRC expression was significantly upregulated in ESCA cells under both oxidative and ER stress conditions, in a dose- and time-dependent manner. Functional assays confirmed that TFRC promotes cell proliferation, migration, and invasion by regulating the HIF-1α and NOTCH1 signaling pathways. This study elucidates the complex interplay between oxidative/ER stress and ESCA progression and highlights the innovative application of bioinformatics to identify potential biomarkers for early diagnosis and therapeutic strategies. Targeting TFRC, in particular, may offer a novel approach to improving ESCA treatment and enhancing patient prognosis.

Potential Molecular Mechanism of Bajitian-Niuxi Formula Delays Intervertebral Disc Degeneration: An Animal Experiment and Network Pharmacology

Intervertebral disc degeneration (IDD) continues to be a major health concern. The combination of Bajitian and Niuxi (B&N) is commonly used to treat musculoskeletal degenerative diseases. This study aimed to explore the potential of B&N in treating IDD through in vivo experiments and bioinformatics approaches. In vivo experiments found that the process of IDD in rats treated with B&N extracts was delayed. Through database screening and network pharmacology analysis, it was discovered that multiple key drug-active ingredients (DAIs) of B&N, such as wogonin, baicalein, 1-hydroxy-3-methoxy-9,10-anthraquinone, and beta-sitosterol, might play a role in the treatment of IDD, among which signaling pathways, such as PI3K-AKT, MAPK, and senescence signaling, might be the main drug-regulated pathways. The binding potential and position of the main DAIs to the core targets were verified by structural bioinformatics. Immunohistochemistry and qRT-PCR results indicated that B&N treatment could improve the expressions of Type II collagen (Col-2) and aggrecan (ACAN) in IDD rats, which might be related to the phosphorylation levels of AKT and p38. Therefore, the B&N formula might delay IDD in rats by regulating multiple signaling pathways through DAIs, which provides new approaches for further exploring the prevention and treatment strategies of IDD with traditional Chinese medicine.

Construction of strontium-loaded injectable lubricating hydrogel and its role in promoting repair of cartilage defects

Injuries such as articular cartilage defects are prevalent factors in the development and progression of joint diseases. The discontinuity of the articular surface due to cartilage defects significantly accelerates the onset of arthritis. Cartilage tissue-engineered scaffolds are essential for restoring the continuity of the articular surface. This study presents a dual-network hydrogel, GelMA-FT/Sr2+, which demonstrates excellent lubrication properties and accelerates the healing of cartilage defects. The hydrogel is composed of a methacrylated gelatin (GelMA) network, an N-fluorenylmethoxycarbonyl-L-tryptophan (FT) network, and strontium ions (Sr2+). The results indicate that the hydrogel exhibits lubricating properties, and the incorporation of Sr2+ extends the degradation time of the hydrogel. Additionally, the hydrogel shows biocompatibility and enhances chondrogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) into cartilage. In vivo studies further confirm the hydrogel's efficacy in promoting the repair of cartilage defects in a rat model of cartilage injury. In conclusion, the GelMA-FT/Sr2+ hydrogel is a promising scaffold for cartilage tissue engineering, notable for its excellent lubrication properties, ability to recruit stem cells, and effectiveness in facilitating cartilage defect repair.

The multifaceted role of phosphodiesterase 4 in tumor: from tumorigenesis to immunotherapy

Phosphodiesterase 4 (PDE4) is an enzyme that specifically hydrolyzes the second messenger cAMP and has a critical role in the regulation of a variety of cellular functions. In recent years, PDE4 has attracted great interest in cancer research, and its role in tumorigenesis and development has been gradually elucidated. Research indicates that abnormal expression or heightened activity of PDE4 is associated with the initiation and progression of multiple cancers, including lung, colorectal, and hematological cancers, by facilitating cell proliferation, migration, invasion, and anti-apoptosis. Moreover, PDE4 also influences the tumor immune microenvironment, significantly immune evasion by suppressing anti-tumor immune responses, reducing T-cell activation, and promoting the polarization of tumor-associated macrophages toward a pro-tumorigenic phenotype. However, the PDE4 family may have both oncogenic and tumor-suppressive effects, which could depend on the specific type and grade of the tumor. PDE4 inhibitors have garnered substantial interest as potential anti-cancer therapeutics, directly inhibiting tumor cell growth and restoring immune surveillance capabilities to enhance the clearance of tumor cells. Several PDE4 inhibitors are currently under investigation with the aim of exploring their potential in cancer therapy, particularly in combination strategies with immune checkpoint inhibitors, to improve therapeutic efficacy and mitigate the side effects of conventional chemotherapy. This review provides an overview of PDE4 in tumorigenesis, drug resistance, immunotherapy, and the anti-tumor actions of its inhibitors, intending to guide the exploration of PDE4 as a new target in tumor therapy.

Unveiling ferroptosis genes and inhibitors in diabetic retinopathy through single-cell analysis and docking simulations

Diabetic retinopathy (DR) is a common microvascular complication of diabetes and a leading cause of vision loss worldwide. Although several mechanisms have been implicated in the pathogenesis of DR, emerging evidence suggests a link between ferroptosis and DR. Unfortunately, the exact mechanism underlying this connection is not clear. Therefore, investigating the role of ferroptosis in diabetic retinopathy holds promise for advancing our understanding of this complex disease and developing innovative treatments. We have identified differentially expressed genes (DEGs) and differentially expressed marker genes (DEMGs) from open-source single-cell RNA sequencing datasets by using in depth in silico approach. Subsequently, ferroptosis-associated DEGs (FA-DEGs), ferroptosis-associated DEMGs (FA-DEMGs), and ferroptosis-associated Hub Genes (FAHGs) were identified. The FDA-approved drugs for our target proteins were also identified, and their ADMET properties were assessed. Molecular docking and simulation were utilized to explore the interaction stability of the compounds with the target proteins. Overall, we identified 63 FA-DEMGs that were significantly enriched in Peroxiredoxin activity, Ferroptosis, Mitophagy, and Autophagy. Further analysis predicted that PRDX1 and UBC are candidate target proteins. Molecular docking results showed that dexamethasone has a high binding affinity for both PRDX1 and UBC. Additionally, molecular dynamics simulations revealed that dexamethasone (which showed the best hit in the docking analysis) exhibited a 'stable effect' on both PRDX1 and UBC. To summarize, this study showed that PRDX1 and UBC could be suitable therapeutic targets for dexamethasone, which might be helpful in the advance of DR treatments in the future.

Hypoxia-inducible factor-1α inhibitor promotes non-alcoholic steatohepatitis development and increases hepatocellular lipid accumulation via TSKU upregulation

Non-alcoholic steatohepatitis (NASH) is the progressive form of non-alcoholic fatty liver disease (NAFLD) which is the most common chronic liver disease worldwide. Hypoxia-inducible factor-1α (HIF1α) inhibitor is emerging as a promising therapeutic strategy for diseases. However, the role of HIF1α inhibitor in NASH is still unclear. A choline-deficient, l-amino acid-defined, high-fat diet (CDAHFD) -induced NASH mouse model was established to identify the impacts of HIF1α inhibitor KC7F2 on the development of NASH. We found that KC7F2 treatment substantially aggravated lipid accumulation, inflammation, and fibrosis in the liver of NASH mice presumably via increasing Tsukushi (TSKU) expression in the liver. Mechanistically, KC7F2 up-regulated expression of TSKU in hepatocyte in vitro, which led to increased hepatocellular lipid accumulation and was reversed when TSKU was knockdown in hepatocyte. Our findings indicated that HIF1α inhibitor promotes the development of NASH presumably via increasing TSKU expression in the liver, suggesting that HIF1α attenuates NASH, and that we should assess the potential liver toxicity when use HIF1α inhibitor or medicines that can decrease the expression of HIF1α to therapy other diseases.

Integrated GelMA and liposome composite hydrogel with effective coupling of angiogenesis and osteogenesis for promoting bone regeneration

In clinical scenarios, bone defects stemming from trauma, infections, degenerative diseases, or hereditary conditions necessitate considerable bone grafts. Researchers ardently focus on creating diverse biomaterials to expedite and enhance these intricate restorative processes. These biomaterials play a pivotal role in aiding osteogenesis and angiogenesis factors for reconstructing stable, fully developed bone tissue. We observed the utilization of Desferoxamine (DFO) facilitated angiogenesis, thereby enabling Kartogenin (KGN) to activate the β-catenin/Runx-2 pathway. Our study introduces a composite hydrogel loaded with KGN and DFO via liposomes to enhance the coupling of angiogenesis and osteogenesis. Within this composite hydrogel system, KGN and DFO undergo effective release. This controlled release substantially promotes a conducive microenvironment for angiogenesis and osteogenesis. Our in vitro studies provide compelling evidence of the synergistic impact between KGN and DFO on osteogenic processes. Moreover, the composite hydrogel exhibits the capability to enhance the expression of proteins and genes associated with both angiogenesis and osteogenesis. In rat skull defect model, the composite hydrogel notably stimulates vascularization and osteogenic differentiation without infection or mortality. In summary, results underscore the potential of this composite hydrogel as an alternative to autografts for bone defect repair, offering a promising approach for future clinical and regenerative applications.

Heterogeneous porous hypoxia-mimicking scaffolds propel urethral reconstruction by promoting angiogenesis and regulating inflammation

The nasty urine microenvironment (UME) impedes neourethral regeneration by inhibiting angiogenesis and inducing an excessive inflammatory response. Cellular adaptation to hypoxia improves regeneration in numerous tissues. In this study, heterogeneous porous hypoxia-mimicking scaffolds were fabricated for urethral reconstruction via promoting angiogenesis and modulating the inflammatory response based on sustained release of dimethyloxalylglycine (DMOG) to promote HIF-1α stabilization. Such scaffolds exhibit a two-layered structure: a dense layer composed of electrospun poly (l-lactic acid) (PLLA) nanofibrous mats and a loose layer composed of a porous gelatin matrix incorporated with DMOG-loaded mesoporous silica nanoparticles (DMSNs) and coated with poly(glycerol sebacate) (PGS). The modification of PGS could significantly increase rupture elongation, making the composite scaffolds more suitable for urethral tissue regeneration. Additionally, sustained release of DMOG from the scaffold facilitates proliferation, migration, tube formation, and angiogenetic gene expression in human umbilical vein endothelial cells (HUVECs), as well as stimulates M2 macrophage polarization and its regulation of HUVECs migration and smooth muscle cell (SMCs) contractile phenotype. These effects were downstream of the stabilization of HIF-1α in HUVECs and macrophages under hypoxia-mimicking conditions. Furthermore, the scaffold achieved better urethral reconstruction in a rabbit urethral stricture model, including an unobstructed urethra with a larger urethral diameter, increased regeneration of urothelial cells, SMCs, and neovascularization. Our results indicate that heterogeneous porous hypoxia-mimicking scaffolds could promote urethral reconstruction via facilitating angiogenesis and modulating inflammatory response.

Qishen Granules Modulate Metabolism Flexibility Against Myocardial Infarction via HIF-1 α-Dependent Mechanisms in Rats

OBJECTIVE

To assess the cardioprotective effect and impact of Qishen Granules (QSG) on different ischemic areas of the myocardium in heart failure (HF) rats by evaluating its metabolic pattern, substrate utilization, and mechanistic modulation.

METHODS

In vivo, echocardiography and histology were used to assess rat cardiac function; positron emission tomography was performed to assess the abundance of glucose metabolism in the ischemic border and remote areas of the heart; fatty acid metabolism and ATP production levels were assessed by hematologic and biochemical analyses. The above experiments evaluated the cardioprotective effect of QSG on left anterior descending ligation-induced HF in rats and the mode of energy metabolism modulation. In vitro, a hypoxia-induced H9C2 model was established, mitochondrial damage was evaluated by flow cytometry, and nuclear translocation of hypoxia-inducible factor-1 α (HIF-1 α) was observed by immunofluorescence to assess the mechanism of energy metabolism regulation by QSG in hypoxic and normoxia conditions.

RESULTS

QSG regulated the pattern of glucose and fatty acid metabolism in the border and remote areas of the heart via the HIF-1 α pathway, and improved cardiac function in HF rats. Specifically, QSG promoted HIF-1 α expression and entry into the nucleus at high levels of hypoxia (P<0.05), thereby promoting increased compensatory glucose metabolism; while reducing nuclear accumulation of HIF-1 α at relatively low levels of hypoxia (P<0.05), promoting the increased lipid metabolism.

CONCLUSIONS

QSG regulates the protein stability of HIF-1 α, thereby coordinating energy supply balance between the ischemic border and remote areas of the myocardium. This alleviates the energy metabolism disorder caused by ischemic injury.

Adrenomedullin Inhibits the Efficacy of Combined Immunotherapy and Targeted Therapy in Biliary Tract Cancer by Disrupting Endothelial Cell Functions

The global incidence of biliary tract cancer (BTC) is on the rise, presenting a substantial healthcare challenge. The integration of immune checkpoint inhibitors (ICIs) with molecularly targeted therapies is emerging as a strategy to enhance immune responses. However, the efficacy and underlying mechanisms of these treatments in BTC are still largely unexplored. In this study, tissue samples from 19 BTC patients treated with camrelizumab and apatinib were analysed using the NanoString 289-panel to identify key molecular biomarkers. Comparative analyses and subsequent experimental validations, including cell-based assays and histopathological examinations, identified adrenomedullin (ADM) as a critical molecular marker associated with treatment efficacy and poor prognosis. ADM has been shown to promote BTC cell proliferation, migration and angiogenesis, primarily by interacting with vascular endothelial growth factor (VEGF) and increasing AKT phosphorylation. Furthermore, ADM disrupts endothelial cell barrier function via the calcitonin receptor-like receptor (CRLR) and vascular endothelial (VE)-cadherin signalling pathway. Preclinical inhibition of ADM or CRLR resulted in suppressed tumour growth. Additionally, elevated ADM expression was correlated with increased tumour-infiltrating immune cells and higher immune checkpoint expression. These findings suggest that ADM plays a pivotal role in resistance to immunotherapy and anti-angiogenic treatment in BTC, and thus, targeting ADM may offer a promising therapeutic approach to enhance treatment efficacy.

HIF-1α Enhances Intestinal Injury and Inflammation in Severe Acute Pancreatitis Through NLRP3 Inflammasome Activation

BACKGROUND

Severe Acute Pancreatitis (SAP) is associated with significant intestinal injury and inflammation. Hypoxia-Inducible Factor-1α (HIF-1α) and NLRP3 inflammasome have been implicated in this process, but their specific roles remain unclear.

OBJECTIVE

This study aims to elucidate the roles of HIF-1α and NLRP3 in the pathogenesis of SAP and their effects on intestinal injury, barrier function, and inflammatory responses.

METHODS

A SAP rat model was established, and histological changes were assessed via HE staining. Western blot was used to analyze HIF-1α and NLRP3 expression in intestinal mucosa. The effects of HIF-1α modulation were examined using the activator DMOG and inhibitor BAY87-2243. Immunohistochemistry, ELISA, and TUNEL staining were used to evaluate intestinal barrier function, permeability markers, and apoptosis.

RESULTS

HIF-1α and NLRP3 expression significantly increased in SAP rats, peaking at 72 h. HIF-1α activation aggravated intestinal injury and barrier dysfunction, decreasing tight junction protein levels and increasing epithelial apoptosis. Enhanced intestinal permeability and elevated pro-inflammatory cytokines were also observed. Furthermore, HIF-1α activation promoted NLRP3 inflammasome assembly, resulting in increased caspase-1 and IL-1β expression.

CONCLUSION

HIF-1α exacerbates intestinal injury and inflammation in SAP, likely through NLRP3 inflammasome activation. Targeting HIF-1α may offer a potential therapeutic approach for SAP-induced damage and inflammation.

Renal mitochondria response to sepsis: a sequential biopsy evaluation of experimental porcine model

BACKGROUND

The pathophysiology of sepsis-induced acute kidney injury remains elusive. Although mitochondrial dysfunction is often perceived as the main culprit, data from preclinical models yielded conflicting results so far. The aim of this study was to assess the immune-metabolic background of sepsis-associated renal dysfunction using sequential biopsy approach with mitochondria function evaluation in a large clinically relevant porcine models mimicking two different paces and severity of sepsis and couple this approach with traditional parameters of renal physiology.

METHODS

In this randomized, open-label study, 15 anaesthetized, mechanically ventilated and instrumented (renal artery flow probe and renal vein catheter) pigs were randomized in two disease severity groups-low severity (LS) sepsis (0.5 g/kg of autologous faeces intraperitoneally) and high severity (HS) sepsis (1 g/kg of autologous faeces intraperitoneally). Sequential cortical biopsies of the left kidney were performed and a pyramid-shaped kidney specimen with cortex, medulla and renal papilla was resected and processed at the end of the experiment. Oxygraphic data and western blot analysis of proteins involved in mitochondrial biogenesis and degradation were obtained.

RESULTS

In contrast to increased mitochondrial activity observed in LS sepsis, a significant decrease in the oxidative phosphorylation capacity together with an increase in the respiratory system uncoupling was observed during the first 24 h after sepsis induction in the HS group. Those changes preceded alterations of renal haemodynamics. Furthermore, serum creatinine rose significantly during the first 24 h, indicating that renal dysfunction is not primarily driven by haemodynamic changes. Compared to cortex, renal medulla had significantly lower oxidative phosphorylation capacity and electron-transport system activity. PGC-1-alfa, a marker of mitochondrial biogenesis, was significantly decreased in HS group.

CONCLUSIONS

In this experimental model, unique sequential tissue data show that the nature and dynamics of renal mitochondrial responses to sepsis are profoundly determined by the severity of infectious challenge and resulting magnitude of inflammatory insult. High disease severity is associated with early and stepwise progression of mitochondria dysfunction and acute kidney injury, both occurring independently from later renal macro-haemodynamic alterations. Our data may help explain the conflicting results of preclinical studies and suggest that sepsis encompasses a very broad spectrum of sepsis-induced acute kidney injury endotypes.

FOXO3a/miR-4259-driven LDHA expression as a key mechanism of gemcitabine sensitivity in pancreatic ductal adenocarcinoma

BACKGROUND

Lactate dehydrogenase A (LDHA) can regulate tumorigenesis and cancer progression. Nevertheless, whether the regulation of LDHA is involved in the development of gemcitabine resistance in PDAC has not yet been fully elucidated. Increasing studies have shown that cancer acquired drug resistance led to treatment failure is highly attributed to the cancer stem cell (CSC) properties. Therefore, we aim to demonstrate the functions and regulatory mechanisms of LDHA on cancer stem cell (CSC) properties and gemcitabine resistance in PDAC.

METHODS

We investigate the metabolite profiles by liquid chromatography-mass spectrometry between gemcitabine-resistant PDAC and parental PDAC cells. Additionally, gain-of-function and loss-of-function experiments were conducted to examine the roles of LDHA on CSC properties and gemcitabine resistance in the gemcitabine-resistant PDAC and parental PDAC cells. To investigate regulators involved in LDHA-mediated gemcitabine resistance and CSC of pancreatic cancer cells, we further used a combination of the miRNA microarray results and software predictions and confirmed that miR-4259 is a direct target of LDHA by luciferase assay. Furthermore, we constructed serial miR-4259 promoter reporters and searched for response elements using the TESS 2.0/TFSEARCH software to find the transcription factor binding site in the promoter region of miR-4259.

RESULTS

We observed that elevated LDHA expression significantly correlates with recurrent pancreatic cancer patients following gemcitabine treatment and with CSC properties. We further identify that FOXO3a-induced miR-4259 directly targets the 3'untranslated region of LDHA and reduced LDHA expression, leading to decreased gemcitabine resistance and a reduction in the CSC phenotypes of pancreatic cancer.

CONCLUSION

Our results demonstrated that LDHA plays a critical role in cancer stemness and gemcitabine resistance of pancreatic cancer, and indicate that targeting the FOXO3a/miR-4259/LDHA pathway might serve as a new treatment for pancreatic cancer patients with a poor response to gemcitabine chemotherapy.

The role of lipids in promoting hair growth through HIF-1 signaling pathway

Understanding the underlying mechanisms regulating hair regeneration is crucial, especially given the increasing demand for effective drugs to treat hair loss, which remain not fully elucidated. In the present study, we found that lipid metabolism was attenuated in the scalp tissues of patients with androgenetic alopecia. Lipid supplementation in the culture medium upregulated hair growth-related genes and promoted the proliferation of human dermal papilla cells (DPCs). By using RNA-sequencing analysis and HIF-1α knockdown in DPCs, we found that HIF-1α is a potential candidate that governs lipid-reinforced upregulation of trichogenic genes. Finally, we assessed the hair growth-promoting effects of lipids using in vitro hair follicle organoids and found that lipids accelerated the elongation of hair-shaft-like structures. Our results highlight the importance of lipids in promoting hair growth through HIF-1 signaling, suggesting that this may be a promising target for the treatment of hair loss.

EZH2 suppresses IR-induced ferroptosis by forming a co-repressor complex with HIF-1α to inhibit ACSL4: Targeting EZH2 enhances radiosensitivity in KDM6A-deficient esophageal squamous carcinoma

The mutation status of the lysine demethylase 6 A (KDM6A), a gene antagonist to Enhancer of zeste homolog 2 (EZH2), is closely related to the therapeutic efficacy of EZH2 inhibitors in several malignancies. However, the mutational landscape of KDM6A and the therapeutic targetability of EZH2 inhibitors in esophageal squamous carcinoma (ESCC) remain unreported. Here, we found that approximately 9.18% (9/98) of our study ESCC tissues had KDM6A mutations of which 7 cases resulted in a complete loss of expression and consequent loss of demethylase function. We found that KDM6A-deficient ESCC cells exhibited increased sensitivity to EZH2 inhibitor, and the radiosensitizing activity of EZH2 inhibitor was evident in KDM6A-dficient ESCC cells. Further transcriptome analysis revealed that ferroptosis is implicated in the radiosensitizing effect exerted by EZH2 inhibition on KDM6A-deficient ESCC cells. The following Chromatin Immunoprecipitation (ChIP), co-immunoprecipitation, and luciferase reporter assays demonstrated that in KDM6A-deficient ESCC cells, (1) Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) is the target gene for EZH2 to regulate ferroptosis; (2) The IR-induced hypoxia inducible factor 1 subunit alpha (HIF-1α) is a predominant mediator of EZH2 to repress ACSL4; (3) the HRE7-8 regions of the ACSL4 promoter are required for the repressive function of EZH2 on ACSL4; (4) EZH2 regulates ACSL4 by forming a co-repressive complex with HIF-1α. Our study provides preclinical evidence supporting that EZH2 inhibitors may confer therapeutic benefit in KDM6A-deficient ESCC patients.

Hypoxia studies in non‑small cell lung cancer: Pathogenesis and clinical implications (Review)

Non‑small cell lung cancer (NSCLC) is one of the most prevalent and lethal types of cancers worldwide and its high incidence and mortality rates pose a significant public health challenge. Despite significant advances in targeted therapy and immunotherapy, the overall prognosis of patients with NSCLC remains poor. Hypoxia is a critical driving factor in tumor progression, influencing the biological behavior of tumor cells through complex molecular mechanisms. The present review systematically examined the role of the hypoxic microenvironment in NSCLC, demonstrating its crucial role in promoting tumor cell growth, invasion and metastasis. Additionally, it has been previously reported that the hypoxic microenvironment enhances tumor cell resistance by activating hypoxia‑inducible factor and regulating exosome secretion. The hypoxic microenvironment also enables tumor cells to adapt to low oxygen and nutrient‑deficient conditions by enhancing metabolic reprogramming, such as through upregulating glycolysis. Further studies have shown that the hypoxic microenvironment facilitates immune escape by modulating tumor‑associated immune cells and suppressing the antitumor response of the immune system. Moreover, the hypoxic microenvironment increases tumor resistance to radiotherapy, chemotherapy and other types of targeted therapy through various pathways, significantly reducing the therapeutic efficacy of these treatments. Therefore, it could be suggested that early detection of cellular hypoxia and targeted therapy based on hypoxia may offer new therapeutic approaches for patients with NSCLC. The present review not only deepened the current understanding of the mechanisms of action and role of the hypoxic microenvironment in NSCLC but also provided a solid theoretical basis for the future development of precision treatments for patients with NSCLC.

Lung tumor organoids migrate as cell clusters containing cancer stem cells under hypoxic condition

BACKGROUND

Tumor hypoxia reshapes the microenvironment, driving progression, invasion, metastasis, and therapy resistance. Patient-derived tumor organoids, formed under three-dimensional conditions, preserve cellular heterogeneity and nutrient gradients, making them ideal for studying hypoxia-induced tumor responses. This study examines hypoxia-induced changes in lung tumor organoids from two patients, focusing on tumor-associated markers, stem cell markers, and migration capabilities.

RESULTS

Our findings demonstrate that hypoxia distinctively modulates the expression of lung cancer markers thyroid transcription factor-1, cytokeratin 7, and ΔNP63 variant. Hypoxia also induces the upregulation of stem cell-associated markers, resulting in an increased proportion of cancer stem cells. Furthermore, hypoxic lung tumor organoids exhibit unique migratory behavior upon reoxygenation, driven by epithelial-mesenchymal transition and the elevated expression of matrix metalloproteinases 7 and matrix metalloproteinases 9, indicating their enhanced invasive potential.

CONCLUSIONS

These findings highlight the value of lung tumor organoids as models for studying hypoxia's complex role in lung cancer. Hypoxia significantly modulates lung tumor organoids growth, stemness, and migratory behavior, providing critical insights into tumor progression and therapy resistance.

Valerenic acid attenuates pathological myocardial hypertrophy by promoting the utilization of multiple substrates in the mitochondrial energy metabolism

INTRODUCTION

Valerenic acid (VA) is a unique and biologically active component in Valeriana officinalis L., which has been reported to have a regulatory effect on the cardiovascular system. However, its therapeutic effects on pathological myocardial hypertrophy (PMH) and the underlying mechanisms are undefined.

OBJECTIVES

Our study aims to elucidate how VA improves PMH, and preliminarily discuss its mechanism.

METHODS

The efficacy of VA on PMH was confirmed by in vivo and in vitro experiments and the underlying mechanism was investigated by molecular dynamics (MD) simulations and specific siRNA interference.

RESULTS

VA enhanced cardiomyocyte fatty acid oxidation (FAO), inhibited hyper-activated glycolysis, and improved the unbalanced pyruvate-lactate axis. VA could significantly improve impaired mitochondrial function and reduce the triglyceride (TG) in the hypertrophic myocardium while reducing the lactate (LD) content. Molecular mechanistic studies showed that VA up-regulated the expression of peroxisome proliferator-activated receptor-α (PPARα) and downstream FAO-related genes including CD36, CPT1A, EHHADH, and MCAD. VA reduced the expression of ENO1 and PDK4, the key enzymes in glycolysis. Meanwhile, VA improved the pyruvate-lactate axis and promoted the aerobic oxidation of pyruvate by inhibiting LDAH and MCT4. MD simulations confirmed that VA can bind with the F273 site of PPARα, which proposes VA as a potential activator of the PPARα.

CONCLUSION

Our results demonstrated that VA might be a potent activator for the PPARα-mediated pathway. VA directly targets the PPARα and subsequently promotes energy metabolism to attenuate PMH, which can be applied as a potentially effective drug for the treatment of HF.

Hypoxia signaling in the adipose tissue

Obesity per se is rapidly emerging all over the planet and further accounts for many other life-threatening conditions, such as diabetes, cardiovascular diseases, and cancers. Decreased oxygen supply or increased relative oxygen consumption in the adipose tissue results in adipose tissue hypoxia, which is a hallmark of obesity. This review aims to provide an up-to-date overview of the hypoxia signaling in the adipose tissue. First, we summarize literature evidence to demonstrate that hypoxia is regularly observed during adipose tissue remodeling in humans and rodent models with obesity. Next, we discuss how hypoxia-inducible factors (HIFs) are regulated and how adipose tissues behave in response to hypoxia. Then, the differential roles of adipose HIF-1α and HIF-2α in adipose tissue biology and obesity pathology are highlighted. Finally, the review emphasizes the importance of modulating adipose hypoxia as a therapeutic avenue to assist adipose tissues in functionally adapting to hypoxic conditions, ultimately promoting adipose health and improving outcomes due to obesity.

Cellular and Molecular Mechanisms Modulated by Genistein in Cancer

Genistein (4',5,7-trihydroxyisoflavone) is a phytoestrogen belonging to a subclass of natural flavonoids that exhibits a wide range of pharmacological functions, including antioxidant and anti-inflammatory properties. These characteristics make genistein a valuable phytochemical compound for the prevention and/or treatment of cancer. Genistein effectively inhibits tumor growth and dissemination by modulating key cellular mechanisms. This includes the suppression of angiogenesis, the inhibition of epithelial-mesenchymal transition, and the regulation of cancer stem cell proliferation. These effects are mediated through pivotal signaling pathways such as JAK/STAT, PI3K/Akt/mTOR, MAPK/ERK, NF-κB, and Wnt/β-catenin. Moreover, genistein interferes with the function of specific cyclin/CDK complexes and modulates the activation of Bcl-2/Bax and caspases, playing a critical role in halting tumor cell division and promoting apoptosis. The aim of this review is to discuss in detail the key cellular and molecular mechanisms underlying the pleiotropic anticancer effects of this flavonoid.

Investigating the role of exosomal long non-coding RNAs in drug resistance within female reproductive system cancers

Exosomes, as key mediators of intercellular communication, have been increasingly recognized for their role in the oncogenic processes, particularly in facilitating drug resistance. This article delves into the emerging evidence linking exosomal lncRNAs to the modulation of drug resistance mechanisms in cancers such as ovarian, cervical, and endometrial cancer. It synthesizes current research findings on how these lncRNAs influence cancer cell survival, tumor microenvironment, and chemotherapy efficacy. Additionally, the review highlights potential therapeutic strategies targeting exosomal lncRNAs, proposing a new frontier in overcoming drug resistance. By mapping the interface of exosomal lncRNAs and drug resistance, this article aims to provide a comprehensive understanding that could pave the way for innovative treatments and improved patient outcomes in female reproductive system cancers.

UBE2Q2 promotes tumor progression and glycolysis of hepatocellular carcinoma through NF-κB/HIF1α signal pathway

PURPOSE

Metabolic reprogramming, particularly the Warburg effect, plays a crucial role in the onset and progression of tumors. The ubiquitin-conjugating enzyme E2 Q2 (UBE2Q2) has been identified overexpressed in hepatocellular carcinoma (HCC). Our aim was to determine if UBE2Q2 plays a role in regulating glycolysis, contributing to the carcinogenesis of HCC.

METHODS

Bioinformatics analysis, western blot and qPCR were used to detect the expression of UBE2Q2. Functional experiments, proteomics analysis and subcutaneous tumors were constructed to find the biological function of UBE2Q2 in HCC. Co-immunoprecipitation, western blot and ubiquitination assays were used to identify the mechanisms involved.

RESULTS

We found a significant association between high UBE2Q2 expression and poor prognosis in HCC patients. Functionally, UBE2Q2 was shown to advance tumor progression in HCC through both in vitro assays and in vivo assessments. Proteomics analysis and glycolysis stress tests corroborated an increase in glycolytic activity due to UBE2Q2. Our findings reveal that UBE2Q2 augments glycolysis by boosting the transcription levels of hypoxia-inducible factor 1α (HIF1α), primarily through the activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. At the molecular level, UBE2Q2 interaction with baculoviral IAP repeat-containing 2 (cIAP1) orchestrates the K63-linked ubiquitination of receptor-interacting serine/threonine-protein kinase 1 (RIP1), which in turn, activates the NF-κB signaling pathway.

CONCLUSIONS

Our investigation reveals that UBE2Q2 regulates the glycolysis in HCC through modulation of the NF-κB/HIF1α signaling pathway, pinpointing UBE2Q2 as a promising therapeutic target for the disease.