LKB1 controls inflammatory potential through CRTC2-dependent histone acetylation

Histone modification inhibitors: An emerging frontier in thyroid Cancer therapy

Thyroid cancer (TC) is the most common endocrine cancer and is a serious health concern due to its aggressiveness and high incidence. Histone modifications affect DNA accessibility and gene transcriptional activity by altering the structure of chromatin. Abnormal histone modifications may affect genome stability and disrupt gene expression patterns, leading to many diseases, including cancer. A growing body of research suggests that histone modifications and TC progression are inextricably linked. This article discusses the impact of aberrant histone modification patterns on TC. By targeting specific histone-modifying enzymes, it may be possible to regulate gene expression and inhibit the growth of TC. Finally, we summarize the relevant histone modification inhibitors to better understand the development stage of the use of these drugs to inhibit histone-modifying enzymes in cancer treatment.

Interleukin-11 expressed in the polyp-enriched fibroblast subset is a potential therapeutic target in Peutz-Jeghers syndrome

Peutz-Jeghers syndrome (PJS) is associated with early-onset gastrointestinal polyposis caused by hereditary inactivating pathogenic variants in the tumor suppressor gene STK11 (LKB1). Due to lack of prophylactic therapies, management of PJS polyps requires frequent surveillance. Interestingly, studies in mouse models have revealed that stromal cells drive the polyp formation, but detailed understanding of the cell types and interactions involved has been lacking. Using single-cell RNA sequencing of PJS mouse model polyps, we here identify a polyp-enriched crypt top fibroblast (pCTF) cluster characterized by a transcriptional signature also enriched in PJS patient polyps. The pCTF signature was also noted in primary fibroblasts in vitro following acute STK11 loss. Targeted deletion of Stk11 in crypt top fibroblasts using Foxl1-Cre led to upregulation of the pCTF signature genes and later to polyposis. pCTFs displayed similarity to inflammation-associated fibroblasts, and polyposis was exacerbated by inflammation. Cell-cell communication analysis identified interleukin 11 (IL-11) as a potential pCTF inducer, and consistent with this, IL-11 was required for fibroblast reprogramming toward pCTFs following STK11 loss. Importantly, a neutralizing IL-11 antibody efficiently reduced polyp formation in a PJS model indicating a key, targetable role for IL-11 in polyp development. Together the results characterize pCTFs as a PJS polyp-enriched fibroblast subset and identify IL-11 as a key mediator of fibroblast reprogramming and a potential therapeutic target in PJS. © 2025 The Pathological Society of Great Britain and Ireland.

Asparagine transporter supports macrophage inflammation via histone phosphorylation

Solute carrier (SLC) family is essential for immune responses; nevertheless, whether and how SLCs regulate macrophage inflammation remains unclear. Here, we demonstrate that K636 acetylation mediates high abundance of SLC6A14 in inflammatory macrophages. Notably, the pharmacological inhibition or genetic modulation of SLC6A14 reduces macrophage interleukin-1β (IL-1β) secretion dependently of lower asparagine uptake and subsequently enhanced nuclear LKB1. Mechanistically, nuclear LKB1 lessens MAPK pathway-mediated NLRP3 inflammasome activation by increased histone 3 S10/28 phosphorylation-dependent cyclin O transcription. Moreover, myeloid Slc6a14 deficiency alleviates pulmonary inflammation via suppressing inflammatory macrophage responses. Overall, these results uncover a network by which SLC6A14-mediated asparagine uptake orchestrates macrophage inflammation through histone phosphorylation, providing a crucial target for modulation of inflammatory diseases.

Gaping conditions of the Pectoralis minor (tenders) in commercial broilers: Prevalence, histology, and gene expression

Gaping is a recently described condition that affects the Pectoralis minor (tender) muscle of broiler chickens, characterized by post-mortem separation of myofiber that leads to meat depreciation and economic losses. In this study, we aimed at understanding prevalence, morphological features, and transcriptomics signatures of this poorly understood myopathy. Between July 2022 and January 2023, a total of 5,180 chicken tenders were collected from 32 flocks across two plants in the USA, handling light (2.7 kg) and heavy (4.1 kg) birds. The prevalence of moderate and severe gaping was 24.8 % and 53.7 %, respectively. The light bird plant had a lower prevalence of moderate gaping (P < 0.001), while the heavy bird plant had a lower prevalence of severe gaping (P < 0.001). Spaghetti meat prevalence from 8,000 fillets was 46.9 % for moderate and 8.3 % for severe cases, with no significant inter-plant differences. Use of peracetic acid treatment at the poultry plants significantly increased the prevalence of severe gaping. Physical and histological features, along with gene expression, were evaluated in 120 samples representative of three gaping severity tiers. Severely gaped tenders showed greater width compared to normal and moderately gaped tenders in both light and heavy birds (P < 0.05). An increase of 1 cm in tender width was associated with a 1.99-fold increase in the odds of classification into a more severe gaping category (95 % CI: 1.15 - 3.46). Affected muscles revealed histological evidence of myodegeneration, inflammation, and lipidosis with fibrosis. For one-unit increase in the myodegeneration score, samples had a 1.75-fold increase in the odds of being classified into a more severe gaping category (95 % CI: 1.37 - 2.23). Gene expression analysis using droplet digital PCR showed differential expression of 19 genes involved in oxidative stress response, cellular signaling, muscle development, and collagen formation between weight groups and myopathy categories. Notably, 21 out of 22 differentially expressed genes showed higher expression in light birds. This study provides the comprehensive description of gaping in broiler chickens and lays a crucial benchmark for assessment of future mitigating strategies.

Glucose uptake in pigment glia suppresses Tau-induced inflammation and photoreceptor degeneration

Brain inflammation contributes to the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease (AD). Glucose hypometabolism and glial activation are pathological features seen in AD brains; however, the connection between the two is not fully understood. Using a Drosophila model of AD, we identified that glucose metabolism in glia plays a critical role in neuroinflammation under disease conditions. Expression of human MATP (hereafter referred to as Tau) in the retinal cells, including photoreceptor neurons and pigment glia, causes photoreceptor degeneration accompanied by the formation of dark-stained round inclusion-like structures and swelling of the lamina cortex. We found that inclusion-like structures are formed by glial phagocytosis, and swelling of the laminal cortex correlates with the expression of antimicrobial peptides. Coexpression of human glucose transporter 3 (SLC2A3, hereafter referred to as GLUT3) with Tau in the retina does not affect Tau levels but suppresses these inflammatory responses and photoreceptor degeneration. We also found that expression of GLUT3, specifically in the pigment glia, is sufficient to suppress inflammatory phenotypes and mitigate photoreceptor degeneration in the Tau-expressing retina. Our results suggest that glial glucose metabolism contributes to inflammatory responses and neurodegeneration in tauopathy.

Exploring the impact of environmental factors on male reproductive health through epigenetics

Male infertility has become an increasingly severe global health issue, with its incidence significantly rising over the past few decades. This paper delves into the crucial role of epigenetics in male reproductive health, focusing particularly on the effects of DNA methylation, histone modifications, chromatin remodeling and non-coding RNAs regulation on spermatogenesis. Exposure to various environmental factors can cause sperm DNA damage, leading to epigenetic abnormalities. Among these factors, we have discussed heavy metals (including Zinc, Cadmium, Arsenic, Copper), phthalates, electromagnetic radiation, and temperature in detail. Notably, aberrations in DNA methylation are closely associated with various symptoms of male infertility, and histone modifications and chromatin remodeling are essential for sperm maturation and function. By synthesizing existing literature and experimental data, this narrative review investigates how environmental factors influence male reproductive health through epigenetic mechanisms, thus providing new theoretical foundations and practical guidelines for the early diagnosis and treatment of male infertility.

Kat7 accelerates osteoarthritis disease progression through the TLR4/NF-κB signaling pathway

Osteoarthritis (OA) is a common degenerative bone and joint disease with an unclear pathogenesis. Our study identified that the histone acetyltransferase encoded by Kat7 is upregulated in the affected articular cartilage of OA patients and in a mice model of medial meniscal instability-induced OA. Chondrocyte-specific knockdown of Kat7 expression exhibited a protective effect on articular cartilage integrity. In vitro experiments demonstrated that KAT7 promotes cartilage catabolism, inhibits cartilage anabolism, and induces chondrocyte senescence and apoptosis. Conversely, knocking down Kat7 was shown to protect chondrocyte function. Corresponding in vivo results indicated that silencing Kat7 effectively enhances cartilage anabolism, prevents articular cartilage damage, and significantly slows OA progression. Mechanistically, KAT7 activates the TLR4/NF-κB signaling pathway, and inhibition of this pathway reverses the catabolic effects and restores anabolic activity in the presence of Kat7 overexpression. Collectively, these findings confirm the critical role of KAT7 in the pathogenesis of OA and suggest that Kat7 represents a potential therapeutic target for OA treatment. KEY MESSAGES: There is a lack of clinically effective drugs for the treatment of osteoarthritis (OA). Kat7 plays a key role in the development of OA. Knocking down Kat7 expression can alleviate the progression of OA. Kat7 accelerates the progression of OA by activating the TLR4/NF-KB signaling pathway.

Spatial proteomics identifies a CRTC-dependent viral signaling pathway that stimulates production of interleukin-11

Appropriate cellular recognition of viruses is essential for the generation of an effective innate and adaptive immune response. Viral sensors and their downstream signaling components thus provide a crucial first line of host defense. Many of them exhibit subcellular relocalization upon activation, resulting in the expression of interferon and antiviral genes. To comprehensively identify signaling factors, we analyzed protein relocalization on a global scale during viral infection. cAMP-responsive element-binding protein (CREB)-regulated transcription coactivators 2 and 3 (CRTC2/3) exhibited early cytoplasmic-to-nuclear translocation upon infection with multiple viruses in diverse cell types. This movement was dependent on mitochondrial antiviral signaling protein (MAVS), cyclo-oxygenase proteins, and protein kinase A. A key effect of CRTC2/3 translocation is transcription of the fibro-inflammatory cytokine interleukin (IL)-11. This may be important clinically in viral infections associated with fibrosis, including SARS-CoV-2. Nuclear translocation of CRTC2/3 is, therefore, identified as an important pathway in the context of viral infection.

Glucose uptake in pigment glia suppresses tau-induced inflammation and photoreceptor degeneration in Drosophila

Brain inflammation contributes to the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD). Glucose hypometabolism and glial activation are pathological features seen in AD brains; however, the connection between the two is not fully understood. Using a Drosophila model of AD, we identified that glucose metabolism in glia plays a critical role in neuroinflammation under disease conditions. Expression of human Tau in the retinal cells, including photoreceptor neurons and pigment glia, causes photoreceptor degeneration accompanied by inclusion formation and swelling of the lamina cortex. We found that inclusions are formed by glial phagocytosis, and swelling of the laminal cortex correlates with the expression of antimicrobial peptides. Co-expression of human glucose transporter 3 ( GLUT3 ) with Tau in the retina does not affect tau levels but suppresses these inflammatory responses and photoreceptor degeneration. We also found that expression of GLUT3 , specifically in the pigment glia, is sufficient to suppress inflammatory phenotypes and mitigate photoreceptor degeneration in the tau-expressing retina. Our results suggest that glial glucose metabolism contributes to inflammatory responses and neurodegeneration in tauopathy.

Summary Statement

Glucose uptake into pigment glia suppresses inflammatory responses and photoreceptor degeneration in the fly model of tauopathy.

DNAJB1-PRKACA Fusion Drives Fibrolamellar Liver Cancer through Impaired SIK Signaling and CRTC2/p300-Mediated Transcriptional Reprogramming

SIGNIFICANCE

This work combines functional studies in model systems and examination of human tumor specimens to define a central oncogenic pathway driven by DNAJB1-PRKACA fusions in FLC. DNAJB1-PRKACA-mediated inactivation of the SIK stimulates CRTC2-p300-mediated transcription to drive tumor growth. The findings illuminate pathogenic mechanisms and inform therapeutic development.

Microbiota governs host chenodeoxycholic acid glucuronidation to ameliorate bile acid disorder induced diarrhea

BACKGROUND

Disorder in bile acid (BA) metabolism is known to be an important factor contributing to diarrhea. However, the pathogenesis of BA disorder-induced diarrhea remains unclear.

METHODS

The colonic BA pool and microbiota between health piglets and BA disorder-induced diarrheal piglets were compared. Fecal microbiota transplantation and various cell experiments further indicated that chenodeoxycholic acid (CDCA) metabolic disorder produced CDCA-3β-glucuronide, which is the main cause of BA disorder diarrhea. Non-targeted metabolomics uncovered the inhibition of the BA glucuronidation by Lactobacillus reuteri (L. reuteri) is through deriving indole-3-carbinol (I3C). In vitro, important gene involved in the reduction of BA disorder induced-diarrhea were screened by RNA transcriptomics sequencing, and activation pathway of FXR-SIRT1-LKB1 to alleviate BA disorder diarrhea and P53-mediated apoptosis were proposed in vitro by multifarious siRNA interference, CO-IP, immunofluorescence, and so on, which mechanism was also verified in a variety of mouse models.

RESULTS

Here, we reveal for the first time that core microbiota derived I3C represses gut epithelium glucuronidation, particularly 3β-glucuronic CDCA production, which reaction is mediated by host UDP glucuronosyltransferase family 1 member A4 (UGT1A4) and necessary of BA disorder induced diarrhea. Mechanistically, L. reuteri derived I3C activates aryl hydrocarbon receptor to decrease UGT1A4 transcription and CDCA-3β-glucuronide content, thereby upregulating FXR-SIRT1-LKB1 signal. LKB1 binds with P53 based on protein interaction, ultimately resists to apoptosis and diarrhea. Moreover, I3C assists CDCA to attain the ameliorative effects of FXR activation in BA disorder diarrhea, through reversion of abnormal metabolism pathway, improving the outcomes of CDCA supplement.

CONCLUSION

These findings uncover the crucial interplay between gut epithelial cells and microbes, highlighting UGT1A4-mediated conversion of CDCA-3β-glucuronide as a key target for ameliorating BA disorder-induced diarrhea. Video Abstract.

Inhibition of ULK1/2 and KRASG12C controls tumor growth in preclinical models of lung cancer

Mutational activation of KRAS occurs commonly in lung carcinogenesis and, with the recent U.S. Food and Drug Administration approval of covalent inhibitors of KRASG12C such as sotorasib or adagrasib, KRAS oncoproteins are important pharmacological targets in non-small cell lung cancer (NSCLC). However, not all KRASG12C-driven NSCLCs respond to these inhibitors, and the emergence of drug resistance in those patients who do respond can be rapid and pleiotropic. Hence, based on a backbone of covalent inhibition of KRASG12C, efforts are underway to develop effective combination therapies. Here, we report that the inhibition of KRASG12C signaling increases autophagy in KRASG12C-expressing lung cancer cells. Moreover, the combination of DCC-3116, a selective ULK1/2 inhibitor, plus sotorasib displays cooperative/synergistic suppression of human KRASG12C-driven lung cancer cell proliferation in vitro and superior tumor control in vivo. Additionally, in genetically engineered mouse models of KRASG12C-driven NSCLC, inhibition of either KRASG12C or ULK1/2 decreases tumor burden and increases mouse survival. Consequently, these data suggest that ULK1/2-mediated autophagy is a pharmacologically actionable cytoprotective stress response to inhibition of KRASG12C in lung cancer.

Inhibition of ULK1/2 and KRAS G12C controls tumor growth in preclinical models of lung cancer

Mutational activation of KRAS occurs commonly in lung carcinogenesis and, with the recent FDA approval of covalent inhibitors of KRAS G12C such as sotorasib or adagrasib, KRAS oncoproteins are important pharmacological targets in non-small cell lung cancer (NSCLC). However, not all KRAS G12C -driven NSCLCs respond to these inhibitors, and the emergence of drug resistance in those patients that do respond can be rapid and pleiotropic. Hence, based on a backbone of covalent inhibition of KRAS G12C , efforts are underway to develop effective combination therapies. Here we report that inhibition of KRAS G12C signaling increases autophagy in KRAS G12C expressing lung cancer cells. Moreover, the combination of DCC-3116, a selective ULK1/2 inhibitor, plus sotorasib displays cooperative/synergistic suppression of human KRAS G12C -driven lung cancer cell proliferation in vitro and superior tumor control in vivo . Additionally, in genetically engineered mouse models of KRAS G12C -driven NSCLC, inhibition of either KRAS G12C or ULK1/2 decreases tumor burden and increases mouse survival. Consequently, these data suggest that ULK1/2-mediated autophagy is a pharmacologically actionable cytoprotective stress response to inhibition of KRAS G12C in lung cancer.

Positive feedback regulation between glycolysis and histone lactylation drives oncogenesis in pancreatic ductal adenocarcinoma

BACKGROUND

Metabolic reprogramming and epigenetic alterations contribute to the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). Lactate-dependent histone modification is a new type of histone mark, which links glycolysis metabolite to the epigenetic process of lactylation. However, the role of histone lactylation in PDAC remains unclear.

METHODS

The level of histone lactylation in PDAC was identified by western blot and immunohistochemistry, and its relationship with the overall survival was evaluated using a Kaplan-Meier survival plot. The participation of histone lactylation in the growth and progression of PDAC was confirmed through inhibition of histone lactylation by glycolysis inhibitors or lactate dehydrogenase A (LDHA) knockdown both in vitro and in vivo. The potential writers and erasers of histone lactylation in PDAC were identified by western blot and functional experiments. The potential target genes of H3K18 lactylation (H3K18la) were screened by CUT&Tag and RNA-seq analyses. The candidate target genes TTK protein kinase (TTK) and BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) were validated through ChIP-qPCR, RT-qPCR and western blot analyses. Next, the effects of these two genes in PDAC were confirmed by knockdown or overexpression. The interaction between TTK and LDHA was identified by Co-IP assay.

RESULTS

Histone lactylation, especially H3K18la level was elevated in PDAC, and the high level of H3K18la was associated with poor prognosis. The suppression of glycolytic activity by different kinds of inhibitors or LDHA knockdown contributed to the anti-tumor effects of PDAC in vitro and in vivo. E1A binding protein p300 (P300) and histone deacetylase 2 were the potential writer and eraser of histone lactylation in PDAC cells, respectively. H3K18la was enriched at the promoters and activated the transcription of mitotic checkpoint regulators TTK and BUB1B. Interestingly, TTK and BUB1B could elevate the expression of P300 which in turn increased glycolysis. Moreover, TTK phosphorylated LDHA at tyrosine 239 (Y239) and activated LDHA, and subsequently upregulated lactate and H3K18la levels.

CONCLUSIONS

The glycolysis-H3K18la-TTK/BUB1B positive feedback loop exacerbates dysfunction in PDAC. These findings delivered a new exploration and significant inter-relationship between lactate metabolic reprogramming and epigenetic regulation, which might pave the way toward novel lactylation treatment strategies in PDAC therapy.

Noval advance of histone modification in inflammatory skin diseases and related treatment methods

Inflammatory skin diseases are a group of diseases caused by the disruption of skin tissue due to immune system disorders. Histone modification plays a pivotal role in the pathogenesis and treatment of chronic inflammatory skin diseases, encompassing a wide range of conditions, including psoriasis, atopic dermatitis, lupus, systemic sclerosis, contact dermatitis, lichen planus, and alopecia areata. Analyzing histone modification as a significant epigenetic regulatory approach holds great promise for advancing our understanding and managing these complex disorders. Additionally, therapeutic interventions targeting histone modifications have emerged as promising strategies for effectively managing inflammatory skin disorders. This comprehensive review provides an overview of the diverse types of histone modification. We discuss the intricate association between histone modification and prevalent chronic inflammatory skin diseases. We also review current and potential therapeutic approaches that revolve around modulating histone modifications. Finally, we investigated the prospects of research on histone modifications in the context of chronic inflammatory skin diseases, paving the way for innovative therapeutic interventions and improved patient outcomes.

Transcriptional co-activators: emerging roles in signaling pathways and potential therapeutic targets for diseases

Specific cell states in metazoans are established by the symphony of gene expression programs that necessitate intricate synergic interactions between transcription factors and the co-activators. Deregulation of these regulatory molecules is associated with cell state transitions, which in turn is accountable for diverse maladies, including developmental disorders, metabolic disorders, and most significantly, cancer. A decade back most transcription factors, the key enablers of disease development, were historically viewed as 'undruggable'; however, in the intervening years, a wealth of literature validated that they can be targeted indirectly through transcriptional co-activators, their confederates in various physiological and molecular processes. These co-activators, along with transcription factors, have the ability to initiate and modulate transcription of diverse genes necessary for normal physiological functions, whereby, deregulation of such interactions may foster tissue-specific disease phenotype. Hence, it is essential to analyze how these co-activators modulate specific multilateral processes in coordination with other factors. The proposed review attempts to elaborate an in-depth account of the transcription co-activators, their involvement in transcription regulation, and context-specific contributions to pathophysiological conditions. This review also addresses an issue that has not been dealt with in a comprehensive manner and hopes to direct attention towards future research that will encompass patient-friendly therapeutic strategies, where drugs targeting co-activators will have enhanced benefits and reduced side effects. Additional insights into currently available therapeutic interventions and the associated constraints will eventually reveal multitudes of advanced therapeutic targets aiming for disease amelioration and good patient prognosis.