Search Results (143)

The limitations of conventional cancer therapies, including toxicity and resistance, underscore the need for safer and more versatile alternatives that can either complement or substitute existing regimens. Garcinol, a polyisoprenylated benzophenone derived primarily from the rind and leaves of Garcinia indica and Garcinia cambogia, has drawn significant interest in recent decades. Although traditionally used to relieve inflammatory disorders, its biomedical relevance expanded considerably after reports in the late 20th century demonstrated antimicrobial and subsequently anti-cancer properties. A growing body of cell-based research, supported by a smaller set of animal experiments, now suggests that garcinol acts as a potent epigenetic modulator. Its activities include inhibition of histone acetyltransferases (HATs), a groundbreaking research followed by regulation of oncogenic microRNAs, and modulation of signaling pathways critical to tumor progression. This review integrates current findings on garcinol’s dual role as a HAT inhibitor and regulator of oncogenic networks with updates on in vitro and in vivo studies with a more focused approach on in vivo animal models, highlighting its potential as an emerging therapeutic against malignancies and inflammatory diseases. Nonetheless, translation into clinical settings remains premature, as robust in vivo evidence is sparse and human trials are lacking. Moving forward, systematic investigations are required to clarify safety profiles, establish effective dosing strategies, and evaluate its efficacy across different cancer types. Full article

The TIP60/NuA4 complex is a large, multifunctional histone acetyltransferase assembly of ~1.7 megadaltons, composed of 17–20 subunits, which plays a central role in epigenetic regulation. Through recognition of H3K4me3 by the ING3 reader, TIP60/NuA4 is recruited to sites of active transcription, where it remodels chromatin to regulate gene expression. Its activities include histone acetylation, histone variant exchange, transcriptional co-activation, and regulation of the cell cycle and apoptosis. In this review, we examine how altered subunit levels or mutations impact the chromatin structure and transcriptional activity, and how these changes influence differentiation across diverse cell types. We emphasize the molecular mechanisms by which TIP60/NuA4 shapes lineage specification, including histone H2A and H4 acetylation by the KAT5 catalytic subunit, H2A.Z incorporation by EP400, and interactions with transcription factors such as MyoD, PPARγ, and Myc. By integrating mechanistic and functional insights, we highlight how TIP60/NuA4 acts as a central epigenetic hub in differentiation and contributes to proper developmental transitions. Full article

We have previously established that bexarotene, a clinically approved agonist of retinoid X receptor (RXR), promotes the differentiation and fusion of skeletal myoblasts. We have also analyzed the genomic programs underlying rexinoid-enhanced myogenic differentiation to identify novel regulatory pathways. As such, we observed a significant upregulation of a transcript encoding a predicted transmembrane protein, Tmem182, during C2C12 myoblast differentiation. Despite the documentation of Tmem182 expression in skeletal muscles, its regulation had yet to be explored. Here, we show that Tmem182 gene expression is markedly augmented in early myoblast differentiation and further enhanced by RXR signaling. In addition, Tmem182 expression is specific to muscle tissues and related to muscle master regulator MyoD. We found that MyoD and histone acetyltransferase p300 are bound to the Tmem182 promoter, and Tmem182 expression is p300-dependent. Thus, our data display a putative epigenetic signature associated with p300 and histone acetylation in rexinoid-responsive locus activation and transcription of myogenic targets. Full article

Background/Objective: Aberrant acetylation and methylation of histone and non-histone proteins contribute to carcinogenesis. Among non-histone proteins, wild-type (wt) p53 is particularly notable for the critical role that acetylation and methylation play in regulating its stability and function. Although with opposite outcomes, these post-translational modifications (PTMs) can also affect mutant forms of p53 (mutp53), which are frequently detected in cancers. These proteins may acquire oncogenic properties, activating signaling pathways that promote carcinogenesis. Acetylation activates wtp53, while this PTM has been shown to destabilize mutp53, reducing cancer aggressiveness and improving the efficacy of anticancer therapies. In this study, we investigated the possibility of targeting mutp53 in pancreatic cancer cells by using a combination of EZH2 and HDAC inhibitors. Methods: Western blotting, qRT-PCR, and ChIP experiments were performed to address this question. Results: We found that the EZH2 inhibitor Valemetostat (DS) in combination with the histone deacetylase inhibitor SAHA displaced the SET/TAF-Iβ oncoprotein from mutp53 and increased its interaction with the acetyltransferase p300, which was responsible for p53 acetylation. Moreover, mutp53 was downregulated, p21 was upregulated, and CHK1 was reduced, increasing DNA damage and leading to a stronger impairment of pancreatic cancer cell survival compared with single-agent treatments. Conclusions: Our results reveal that combining epigenetic drugs such as Valemetostat and SAHA could be exploited to target mutp53 and improve the outcome of treatments for aggressive tumors harboring it, such as in pancreatic cancer. Full article

Type 2 Diabetes Mellitus (T2DM) is increasingly affecting individuals across various age groups due to inadequate insulin action and secretion. It has become the leading cause of mortality worldwide, with an estimated 9.3% of the global population currently affected. Recent epigenetic studies have shown that variations such as DNA methylation and histone modifications are implicated in the development of T2DM. However, epigenetically related conditions are known to be reversible, which could potentially pave the way for predicting and treating T2DM. This has led to the development of epigenetic modifier drugs, including histone deacetylase inhibitors (HDACi), histone acetyltransferase inhibitors (HATi), protein arginine methyltransferase inhibitors (PRMTi), DNA methyltransferase inhibitors (DNMTi), histone demethylating inhibitors (HDMi), and sirtuin-activating compounds (STAC). A major challenge with these epigenetic drugs is that only a few have been approved for treating metabolic diseases due to their potential to negatively impact off-target genes. The low specificity of these drugs can lead to side effects and increased toxicity, contributing to complex diseases such as cancer. Hence, gaining a comprehensive understanding of the epigenetic mechanisms underlying metabolic diseases can provide new insights and strategies for preventing, diagnosing, and treating metabolic disorders, such as T2DM. This review summarizes the epigenetic variations in T2DM, pharmaco-epigenetics, and the challenges surrounding epigenetics. This provides basic insight into the discovery of novel drug targets, which can lead to the development of epigenetic therapies for T2DM. Hence, the reversible nature of epigenetic variations retains hope for future novel strategies to combat T2DM. Full article

Asthma is a chronic inflammatory airway disease influenced by both genetic and environmental factors. Recent insights have underscored the pivotal role of epigenetic regulation in the pathogenesis and heterogeneity of asthma. This review focuses on key epigenetically important regulators categorized as writers, erasers, and readers that govern DNA methylation, histone modifications, and RNA modifications. These proteins modulate gene expression without altering the underlying DNA sequence, thereby influencing immune responses, airway remodeling, and disease severity. We highlight the structural and functional dynamics of histone acetyltransferases (e.g., p300/CBP), histone deacetylases (e.g., SIRT family), DNA methyltransferases (DNMT1, DNMT3A), demethylases (TET1), and methyl-CpG-binding proteins (MBD2) in shaping chromatin accessibility and transcriptional activity. Additionally, the m6A RNA modification machinery including METTL3, METTL14, FTO, YTHDF1/2, IGF2BP2, and WTAP is explored for its emerging significance in regulating post-transcriptional gene expression during asthma progression. Structural characterizations of these proteins reveal conserved catalytic domains and interaction motifs, mirroring their respective families such as SIRTs, p300/CBP, DNMT1/3A, and YTHDF1/2 critical to their epigenetic functions, offering mechanistic insight into their roles in airway inflammation and immune modulation. By elucidating these pathways, this review provides a framework for the development of epigenetic biomarkers and targeted therapies. Future directions emphasize phenotype-specific epigenomic profiling and structure-guided drug design to enable precision medicine approaches in asthma management. Full article

Ischemic brain and retinal injuries trigger complex molecular cascades involving neuroinflammation, oxidative stress, and neuronal death. Among these mechanisms, epigenetic regulation has emerged as a critical modulator of the injury response. Histone deacetylases (HDACs) and histone acetyltransferases (HATs) dynamically control gene expression by altering chromatin structure. HDACs often promote neuroinflammation and neuronal apoptosis through repression of neuroprotective and anti-inflammatory genes, while HATs generally enhance the transcription of genes involved in cell survival and repair. In ischemia, specific HDAC isoforms (e.g., HDAC1, HDAC2, HDAC3, and HDAC6) have been implicated in microglial activation, glial reactivity, and disruption of immune balance. Conversely, HATs such as CBP/p300 and Tip60 contribute to neuronal resilience and immune regulation. Understanding the dual and context-dependent roles of these epigenetic enzymes offers promising therapeutic avenues. Selective HDAC inhibitors or HAT activators may represent novel strategies to mitigate ischemic damage, support neuroprotection, and facilitate functional recovery. Full article

Uterine leiomyomas (ULM) and uterine leiomyosarcomas (ULMS) represent smooth muscle tumors with similar initial presentations but drastically different outcomes. This literature review analyzes the similarities and differences in their epigenetic profiles to identify diagnostic biomarkers and potential therapeutic targets that could improve clinical management. Both tumor types exhibit mostly distinct epigenetic signatures while sharing key pathway dysregulations. ULMS demonstrates global DNA hypomethylation, increased histone acetyltransferase activity, elevated Histone Deacetylase (HDAC) class I expression, and characteristic microRNA profiles. ULM displays focal methylation patterns and specific microRNA alterations that promote extracellular matrix accumulation. Despite these differences in epigenetic mechanisms, both tumors converge on dysregulation of signaling pathways including PI3K/AKT/mTOR, Wnt/β-catenin, and Transforming Growth Factor beta (TGF-β) signaling, suggesting common downstream effects from distinct epigenetic origins. Understanding the shared and distinct epigenetic landscape between ULM and ULMS will enhance our insights into tumor pathogenesis and may offer promising biomarkers and therapeutic targets. Full article

In this study, we investigated the mitochondrial defects resulting from the deletion of GCN5, a lysine-acetyltransferase, in the yeast Saccharomyces cerevisiae. Gcn5 serves as the catalytic subunit of the SAGA acetylation complex and functions as an epigenetic regulator, primarily acetylating N-terminal lysine residues on histones H2B and H3 to modulate gene expression. The loss of GCN5 leads to mitochondrial abnormalities, including defects in mitochondrial morphology, a reduced mitochondrial DNA copy number, and defective mitochondrial inheritance due to the depolarization of actin filaments. These defects collectively trigger the activation of the mitophagy pathway. Interestingly, deleting CSN5, which encodes to Csn5/Rri1 (Csn5), the catalytic subunit of the COP9 signalosome complex, rescues the mitochondrial phenotypes observed in the gcn5Δ strain. Furthermore, these defects are suppressed by exogenous ergosterol supplementation, suggesting a link between the rescue effect mediated by CSN5 deletion and the regulatory role of Csn5 in the ergosterol biosynthetic pathway. Full article

Aurora kinase B (AURKB), a serine/threonine protein kinase, is essential for accurate chromosome segregation and cytokinesis during mitosis. Dysregulation of AURKB, often characterized by its overexpression, has been implicated in various malignancies, including breast cancer. However, the mechanisms governing its dysregulation remain incompletely understood. Here, we identify a pivotal role for the MOF/MSL complex—which includes the histone acetyltransferase MOF (KAT8)—in modulating AURKB stability through acetylation at lysine 215 (K215). This post-translational modification inhibits AURKB ubiquitination, thereby stabilizing its protein levels. MOF/MSL-mediated AURKB stabilization promotes the proper assembly of the chromosomal passenger complex (CPC), ensuring mitotic fidelity. Notably, inhibition of MOF reduces AURKB K215 acetylation, leading to decreased AURKB expression and activity. Consequently, this downregulation suppresses expression of the downstream oncogene c-MYC, ultimately attenuating the malignant proliferation of breast cancer cells. Collectively, our findings reveal a novel mechanism by which lysine acetylation regulates AURKB stability, highlight the significance of the MOF-AURKB-c-MYC axis in breast cancer progression, and suggest potential therapeutic strategies targeting this pathway in clinical settings. Full article

Lysine acetyltransferase 8 (KAT8) is a member of the MYST family of histone acetyltransferases. It catalyzes the acetylation of histone H4 at lysine 16 (H4K16ac) and non-histone proteins. Abnormal upregulation or downregulation of KAT8 and its associated H4K16ac have been observed in malignant tumors, suggesting its close association with tumorigenesis and progression. Characterized by structural diversity and multi-target mechanisms, natural agents have been increasingly shown to possess significant antitumor activity. This review focuses on KAT8, summarizing its molecular mechanisms in regulating tumor development by catalyzing substrate protein acetylation, which impacts tumor cell proliferation, cell cycle regulation, apoptosis, DNA damage repair, and autophagy. It also systematically discusses the pharmacological activities and molecular mechanisms of small-molecule agents that target KAT8 to inhibit tumor proliferation, including natural compounds, synthetic drugs, and non-coding RNAs. Full article

Fibrosis is a pathological process characterized by excessive extracellular matrix (ECM) deposition, leading to tissue stiffening and organ dysfunction. It is a major contributor to chronic diseases affecting various organs, with limited therapeutic options available. Among the different forms of fibrosis, cardiac fibrosis is particularly relevant due to its impact on cardiovascular diseases (CVDs), which remain the leading cause of morbidity and mortality worldwide. This process is driven by activated cardiac fibroblasts (CFs), which promote ECM accumulation in response to chronic stressors. Epigenetic mechanisms, including DNA methylation, histone modifications, and chromatin remodeling, are key regulators of fibroblast activation and fibrotic gene expression. Enzymes such as DNA methyltransferases (DNMTs), histone methyltransferases (HMTs), histone acetyltransferases (HATs), and histone deacetylases (HDACs) have emerged as potential therapeutic targets, and epigenetic inhibitors have shown promise in modulating these enzymes to attenuate fibrosis by controlling fibroblast function and ECM deposition. These small-molecule compounds offer advantages such as reversibility and precise temporal control, making them attractive candidates for therapeutic intervention. This review aims to provide a comprehensive overview of the mechanisms by which epigenetic regulators influence cardiac fibrosis and examines the latest advances in preclinical epigenetic therapies. By integrating recent data from functional studies, single-cell profiling, and drug development, it highlights key molecular targets, emerging therapeutic strategies, and current limitations, offering a critical framework to guide future research and clinical translation. Full article

Cisplatin is a widely used DNA-targeting anticancer drug. Histone deacetylase inhibitors (HDACi) cause histone hyperacetylation, changing chromatin structure and accessibility of genomic DNA by the genotoxic drug. As a consequence, HDACi could promote cisplatin cytotoxicity. Hence, the underlying mechanisms by which HDACi alter the action pathways of cisplatin to promote its anticancer activity have attracted increasing attention during the past decades. It has been commonly accepted that HDACi elevate the acetylation level of histones to release genomic DNA to cisplatin attack, increasing the level of cisplatin-induced DNA lesions to promote cisplatin cytotoxicity. However, how the HDACi-enhanced cisplatin lesion on DNA impacts the downstream biological processes, and whether the promotion of HDACi to cisplatin activity is attributed to their inherent anticancer activity or to their induced elevation of histone acetylation, have been in debate. Several studies showed that HDACi-enhanced DNA lesion could promote cisplatin-induced apoptosis, cell cycle arrest, and reactive oxygen species (ROS) generation, subsequently promoting cisplatin efficiency. In contrast, HDACi-induced elimination of ROS and inhibition of ferroptosis were thought to be the main ways by which HDACi protect kidneys from acute injury caused by cisplatin. Based on our recent research, we herein review and discuss the advances in research on the mechanisms of HDACi-induced enhancement in cisplatin cytotoxicity. Given that histone acetyltransferase (HAT) inhibitors also show an effect enhancing cisplatin cytotoxicity, we will discuss the diverse roles of histone acetylation in cancer therapy in addition to the synergistic anticancer effect and potential of HDACi with genotoxic drugs and radiotherapy. Full article

Background/Objectives: Cucumber (Cucumis sativus) provides a model for exploring the molecular basis of sex determination, particularly the regulation of floral organ differentiation through gene expression. This complex process is modulated by epigenetic factors, such as histone acetyltransferases (HATs) and histone deacetylases (HDACs), which respectively activate and repress gene transcription by adding or removing acetyl groups from histone proteins. Despite their known functions, the roles of HATs and HDACs throughout cucumber’s floral developmental stages remain unclear. Methods: In this study, we conducted a genome-wide analysis of HAT and HDAC gene families in cucumber, examining their phylogenetic relationships, gene structures, protein domains, and expression profiles across various stages of floral development. Results: We identified 36 CsHAT and 12 CsHDAC genes, grouping them into families with evolutionary counterparts in other plant species. RNA sequencing revealed stage-specific expression patterns, suggesting dynamic roles for these gene families in floral organ development. Conclusions: These findings contribute valuable insights into the epigenetic regulation of gene expression in cucumber flower formation, presenting avenues for further research on the genetic control of plant reproductive development. Full article

Phyllanthus emblica is widely used in Ayurvedic preparations against multiple disorders and contains various bioactive components. This study aimed to determine the preventive effect of P. emblica on obesity by evaluating the inhibition of adipogenesis and the related regulatory epigenetic mechanisms during 3T3-L1 differentiation. The ethyl acetate fraction of P. emblica (EFPE) effectively inhibited lipid accumulation and triglyceride (TG) production in 3T3-L1 adipocytes. It also inhibited histone acetyltransferase (HAT) activity and regulated Pcaf-specific H3K9 acetylation and the expression of adipogenesis-related genes during adipocyte differentiation. Phenolic compounds were the main components of EFPE, of which gallic acid (GA) exhibited the strongest inhibitory effect on lipid accumulation and TG production. Notably, GA effectively regulated adipogenesis-mediated gene expression through H3K9 acetylation. These findings, along with the experiment results, suggest that EFPE containing GA is a potent agent for preventing obesity by regulating H3K9 acetylation. Full article