Disruption of β-catenin/CBP signaling inhibits human airway epithelial-mesenchymal transition and repair

Competitive-like binding between carbon black and CTNNB1 to ΔNp63 interpreting the abnormal respiratory epithelial repair after injury

Airway epithelium is extraordinary vulnerable to damage owning to continuous environment exposure. Subsequent repair is therefore essential to restore the homeostasis of respiratory system. Disruptions in respiratory epithelial repair caused by nanoparticles exposure have been linked to various human diseases, yet implications in repair process remain incompletely elucidated. This study aims to elucidate the key stage in epithelial repair disturbed by carbon black (CB) nanoparticles, highlighting the pivotal role of ΔNp63 in mediating the epithelium repair. A competitive-like binding between CB and beta-catenin 1 (CTNNB1) to ΔNp63 is proposed to elaborate the underlying toxicity mechanism. Specifically, CB exhibits a remarkable inhibitory effect on cell proliferation, leading to aberrant airway epithelial repair, as validated in air-liquid culture. ΔNp63 drives efficient epithelial proliferation during CB exposure, and CTNNB1 was identified as a target of ΔNp63 by bioinformatics analysis. Further molecular dynamics simulation reveals that oxygen-containing functional groups on CB disrupt the native interaction of CTNNB1 with ΔNp63 through competitive-like binding pattern. This process modulates CTNNB1 expression, ultimately restraining proliferation during respiratory epithelial repair. Overall, the current study elucidates that the diminished interaction between CTNNB1 and ΔNp63 impedes respiratory epithelial repair in response to CB exposure, thereby enriching the public health risk assessment on CB-related respiratory diseases.

The involvement of the Wnt/β-catenin signaling cascade in fibrosis progression and its therapeutic targeting by relaxin

Organ scarring, referred to as fibrosis, results from a failed wound-healing response to chronic tissue injury and is characterised by the aberrant accumulation of various extracellular matrix (ECM) components. Once established, fibrosis is recognised as a hallmark of stiffened and dysfunctional tissues, hence, various fibrosis-related diseases collectively contribute to high morbidity and mortality in developed countries. Despite this, these diseases are ineffectively treated by currently-available medications. The pro-fibrotic cytokine, transforming growth factor (TGF)-β1, has emerged as the master regulator of fibrosis progression, owing to its ability to promote various factors and processes that facilitate rapid ECM synthesis and deposition, whilst negating ECM degradation. TGF-β1 signal transduction is tightly controlled by canonical (Smad-dependent) and non-canonical (MAP kinase- and Rho-associated protein kinase-dependent) intracellular protein activity, whereas its pro-fibrotic actions can also be facilitated by the Wnt/β-catenin pathway. This review outlines the pathological sequence of events and contributing roles of TGF-β1 in the progression of fibrosis, and how the Wnt/β-catenin pathway contributes to tissue repair in acute disease settings, but to fibrosis and related tissue dysfunction in synergy with TGF-β1 in chronic diseases. It also outlines the anti-fibrotic and related signal transduction mechanisms of the hormone, relaxin, that are mediated via its negative modulation of TGF-β1 and Wnt/β-catenin signaling, but through the promotion of Wnt/β-catenin activity in acute disease settings. Collectively, this highlights that the crosstalk between TGF-β1 signal transduction and the Wnt/β-catenin cascade may provide a therapeutic target that can be exploited to broadly treat and reverse established fibrosis.

Approach for Elucidating the Molecular Mechanism of Epithelial to Mesenchymal Transition in Fibrosis of Asthmatic Airway Remodeling Focusing on Cl- Channels

Airway remodeling caused by asthma is characterized by structural changes of subepithelial fibrosis, goblet cell metaplasia, submucosal gland hyperplasia, smooth muscle cell hyperplasia, and angiogenesis, leading to symptoms such as dyspnea, which cause marked quality of life deterioration. In particular, fibrosis exacerbated by asthma progression is reportedly mediated by epithelial-mesenchymal transition (EMT). It is well known that the molecular mechanism of EMT in fibrosis of asthmatic airway remodeling is closely associated with several signaling pathways, including the TGF-β1/Smad, TGF-β1/non-Smad, and Wnt/β-catenin signaling pathways. However, the molecular mechanism of EMT in fibrosis of asthmatic airway remodeling has not yet been fully clarified. Given that Cl- transport through Cl- channels causes passive water flow and consequent changes in cell volume, these channels may be considered to play a key role in EMT, which is characterized by significant morphological changes. In the present article, we highlight how EMT, which causes fibrosis and carcinogenesis in various tissues, is strongly associated with activation or inactivation of Cl- channels and discuss whether Cl- channels can lead to elucidation of the molecular mechanism of EMT in fibrosis of asthmatic airway remodeling.

A roadmap for developing and engineering in vitro pulmonary fibrosis models

Idiopathic pulmonary fibrosis (IPF) is a severe form of pulmonary fibrosis. IPF is a fatal disease with no cure and is challenging to diagnose. Unfortunately, due to the elusive etiology of IPF and a late diagnosis, there are no cures for IPF. Two FDA-approved drugs for IPF, nintedanib and pirfenidone, slow the progression of the disease, yet fail to cure or reverse it. Furthermore, most animal models have been unable to completely recapitulate the physiology of human IPF, resulting in the failure of many drug candidates in preclinical studies. In the last few decades, the development of new IPF drugs focused on changes at the cellular level, as it was believed that the cells were the main players in IPF development and progression. However, recent studies have shed light on the critical role of the extracellular matrix (ECM) in IPF development, where the ECM communicates with cells and initiates a positive feedback loop to promote fibrotic processes. Stemming from this shift in the understanding of fibrosis, there is a need to develop in vitro model systems that mimic the human lung microenvironment to better understand how biochemical and biomechanical cues drive fibrotic processes in IPF. However, current in vitro cell culture platforms, which may include substrates with different stiffness or natural hydrogels, have shortcomings in recapitulating the complexity of fibrosis. This review aims to draw a roadmap for developing advanced in vitro pulmonary fibrosis models, which can be leveraged to understand better different mechanisms involved in IPF and develop drug candidates with improved efficacy. We begin with a brief overview defining pulmonary fibrosis and highlight the importance of ECM components in the disease progression. We focus on fibroblasts and myofibroblasts in the context of ECM biology and fibrotic processes, as most conventional advanced in vitro models of pulmonary fibrosis use these cell types. We transition to discussing the parameters of the 3D microenvironment that are relevant in pulmonary fibrosis progression. Finally, the review ends by summarizing the state of the art in the field and future directions.

The role of β-catenin in cardiac diseases

The Wnt/β-catenin signaling pathway is a classical Wnt pathway that regulates the stability and nuclear localization of β-catenin and plays an important role in adult heart development and cardiac tissue homeostasis. In recent years, an increasing number of researchers have implicated the dysregulation of this signaling pathway in a variety of cardiac diseases, such as myocardial infarction, arrhythmias, arrhythmogenic cardiomyopathy, diabetic cardiomyopathies, and myocardial hypertrophy. The morbidity and mortality of cardiac diseases are increasing, which brings great challenges to clinical treatment and seriously affects patient health. Thus, understanding the biological roles of the Wnt/β-catenin pathway in these diseases may be essential for cardiac disease treatment and diagnosis to improve patient quality of life. In this review, we summarize current research on the roles of β-catenin in human cardiac diseases and potential inhibitors of Wnt/β-catenin, which may provide new strategies for cardiac disease therapies.

Inhibition of β-Catenin/CREB Binding Protein Signaling Attenuates House Dust Mite-Induced Goblet Cell Metaplasia in Mice

Excessive mucus production is a major feature of allergic asthma. Disruption of epithelial junctions by allergens such as house dust mite (HDM) results in the activation of β-catenin signaling, which has been reported to stimulate goblet cell differentiation. β-catenin interacts with various co-activators including CREB binding protein (CBP) and p300, thereby regulating the expression of genes involved in cell proliferation and differentiation, respectively. We specifically investigated the role of the β-catenin/CBP signaling pathway in goblet cell metaplasia in a HDM-induced allergic airway disease model in mice using ICG-001, a small molecule inhibitor that blocks the binding of CBP to β-catenin. Female 6- 8-week-old BALB/c mice were sensitized to HDM/saline on days 0, 1, and 2, followed by intranasal challenge with HDM/saline with or without subcutaneous ICG-001/vehicle treatment from days 14 to 17, and samples harvested 24 h after the last challenge/treatment. Differential inflammatory cells in bronchoalveolar lavage (BAL) fluid were enumerated. Alcian blue (AB)/Periodic acid–Schiff (PAS) staining was used to identify goblet cells/mucus production, and airway hyperresponsiveness (AHR) was assessed using invasive plethysmography. Exposure to HDM induced airway inflammation, goblet cell metaplasia and increased AHR, with increased airway resistance in response to the non-specific spasmogen methacholine. Inhibition of the β-catenin/CBP pathway using treatment with ICG-001 significantly attenuated the HDM-induced goblet cell metaplasia and infiltration of macrophages, but had no effect on eosinophils, neutrophils, lymphocytes or AHR. Increased β-catenin/CBP signaling may promote HDM-induced goblet cell metaplasia in mice.

Eosinophils Correlate with Epithelial-Mesenchymal Transition in Chronic Rhinosinusitis with Nasal Polyps

INTRODUCTION

Chronic inflammation and tissue remodeling always occur together in chronic rhinosinusitis (CRS). Epithelial-mesenchymal transition (EMT) plays a critical role in airway remodeling.

OBJECTIVE

Changes of epithelial cells in sinus mucosa in different subtypes of CRS, especially in eosinophilic chronic rhinosinusitis with nasal polyps, and the role of EMT and eosinophils (EOS) in airway remodeling are still unknown.

METHODS

We included 85 patients in this study. They were divided into 4 groups: a normal control (NC) group, a chronic rhinosinusitis without nasal polyps (CRSsNP) group, an eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) group, and a noneosinophilic chronic rhinosinusitis with nasal polyps (non-ECRSwNP) group. Clinical data were all collected and analyzed. Standard hematoxylin and eosin staining, immunohistochemical staining, and 2-color immunofluorescence staining were performed. Biomarkers of EMT, epithelial cadherin, and vimentin were labeled. The immunohistochemistry results of each group were counted and statistically analyzed.

RESULTS AND CONCLUSION

E-cadherin was downregulated, and vimentin was upregulated in epithelial tissue from the ECRSwNP group, compared with that from the control group and the other groups. The number of vimentin-expressing epithelial cells correlated with sinus CT imaging Lund-Mackay scores (r = 0.560, p < 0.001). Moreover, expression levels of vimentin in the epithelium were associated with numbers of infiltrating EOS in tissues (r = 0.710, p < 0.001) and the peripheral blood EOS ratio (r = 0.594, p < 0.001). EMT occurred in patients with CRSwNP, especially in those with ECRSwNP. Epithelial reprogramming correlates with eosinophil infiltration and disease severity. Eosinophils contributed to impairment of epithelial function and promoted EMT in CRSwNP.

Anti-VEGF treatment suppresses remodeling factors and restores epithelial barrier function through the E-cadherin/β-catenin signaling axis in experimental asthma models

Besides maintaining a physical barrier with adherens junctional (AJ) and tight junctional proteins, airway epithelial cells have important roles in modulating the inflammatory processes of allergic asthma. E-cadherin and β-catenin are the key AJ proteins that are involved in airway remodeling. Various mediators such as transforming growth factor-β (TGF-β), epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet derived growth factor (PDGF), insulin-like growth factor (IGF), tumor necrosis factor-α (TNF-α) and angiogenic factors, such as vascular endothelial growth factor (VEGF), are released by the airway epithelium in allergic asthma. The signaling pathways activated by these growth factors trigger epithelial-mesenchymal transition (EMT), which contributes to fibrosis and subsequent downregulation of E-cadherin. The present study used a mouse asthma model to investigate the effects of anti-VEGF, anti-TNF and corticosteroid therapies on growth factor and E-cadherin/β-catenin expression. The study used 38 male BALB/c mice, divided into 5 groups. A chronic mouse asthma model was created by treating 4 of the groups with inhaled and intraperitoneal ovalbumin (n= 8 per group). Saline, anti-TNF-α (etanercept), anti-VEGF (bevacizumab) or a corticosteroid (dexamethasone) were applied to each group by intraperitoneal injection. No medication was administered to the control group (n=6). Immunohistochemistry for E-cadherin, β-catenin and growth factors was performed on lung tissues and protein expression levels assessed using H-scores. Statistically significant differences were observed in E-cadherin, β-catenin, EGF, FG, and PFGF (P<0.001 for all) as well as the IGF H-scores between the five groups (P<0.005). Only anti-VEGF treatment caused E-cadherin and β-catenin levels to increase to the level of non-asthmatic control groups (P>0.005). All treatment groups had reduced TGF-β, PDGF and FGF H-scores in comparison with the untreated asthma group (P=0.001). The EGF and IGF levels were not significantly different between the untreated asthmatic and non-asthmatic controls. The results suggested that anti-VEGF and TNF-α inhibition treatments are effective in decreasing growth factors, in a similar manner to conventional corticosteroid treatments. Anti-VEGF and TNF inhibition therapy may be an effective treatment for remodeling in asthma while offering an alternative therapeutic option to steroid protective agents. The data suggested that anti-VEGF treatment offered greater restoration of the epithelial barrier than both anti-TNF-α and corticosteroid treatment.

A Study of the Ionic Liquid-Based Ultrasonic-Assisted Extraction of Isoliquiritigenin from Glycyrrhiza uralensis

We successfully extracted isoliquiritigenin from Glycyrrhiza uralensis through the utilization of an ionic liquid-based ultrasonic-assisted extraction (ILUAE) approach. Briefly, we utilized the solution of 1-butyl-3-methylimidazolium bromide ([BMIM]Br) as solvent and optimized key ILUAE parameters such as solid-liquid ratios, concentrations of ionic liquids, and the times of ultrasonication. Based on a single-factor experiment, we utilized the response surface method (RSM) approach to optimize the extraction procedure. The approach revealed that the optimal energy consumption time was 120 min, with the ultrasonic extraction temperature of 60°C. Using these optimized parameters together with the solid-liquid ratio (dried G. uralensis powder: [BMIM]Br of 0.3 mol/L) of 1 : 16.163 and the [BMIM]Br of 0.3 mol/L, we achieved a 0.665 mg/g extraction yield. Overall, these findings thus indicate that we were able to effectively use ILUAE as an efficient approach to reliably extract isoliquiritigenin in a reproducible and environmentally friendly manner.

Azithromycin Partially Mitigates Dysregulated Repair of Lung Allograft Small Airway Epithelium

BACKGROUND

Dysregulated airway epithelial repair following injury is a proposed mechanism driving posttransplant bronchiolitis obliterans (BO), and its clinical correlate bronchiolitis obliterans syndrome (BOS). This study compared gene and cellular characteristics of injury and repair in large (LAEC) and small (SAEC) airway epithelial cells of transplant patients.

METHODS

Subjects were recruited at the time of routine bronchoscopy posttransplantation and included patients with and without BOS. Airway epithelial cells were obtained from bronchial and bronchiolar brushing performed under radiological guidance from these patients. In addition, bronchial brushings were also obtained from healthy control subjects comprising of adolescents admitted for elective surgery for nonrespiratory-related conditions. Primary cultures were established, monolayers wounded, and repair assessed (±) azithromycin (1 µg/mL). In addition, proliferative capacity as well as markers of injury and dysregulated repair were also assessed.

RESULTS

SAEC had a significantly dysregulated repair process postinjury, despite having a higher proliferative capacity than large airway epithelial cells. Addition of azithromycin significantly induced repair in these cells; however, full restitution was not achieved. Expression of several genes associated with epithelial barrier repair (matrix metalloproteinase 7, matrix metalloproteinase 3, the integrins β6 and β8, and β-catenin) were significantly different in epithelial cells obtained from patients with BOS compared to transplant patients without BOS and controls, suggesting an intrinsic defect.

CONCLUSIONS

Chronic airway injury and dysregulated repair programs are evident in airway epithelium obtained from patients with BOS, particularly with SAEC. We also show that azithromycin partially mitigates this pathology.

Transcriptomic and barrier responses of human airway epithelial cells exposed to cannabis smoke

Globally, many jurisdictions are legalizing or decriminalizing cannabis, creating a potential public health issue that would benefit from experimental evidence to inform policy, government regulations, and user practices. Tobacco smoke exposure science has created a body of knowledge that demonstrates the conclusive negative impacts on respiratory health; similar knowledge remains to be established for cannabis. To address this unmet need, we performed in vitro functional and transcriptomic experiments with a human airway epithelial cell line (Calu-3) exposed to cannabis smoke, with tobacco smoke as a positive control. Demonstrating the validity of our in vitro model, tobacco smoke induced gene expression profiles that were significantly correlated with gene expression profiles from published tobacco exposure datasets from bronchial brushings and primary human airway epithelial cell cultures. Applying our model to cannabis smoke, we demonstrate that cannabis smoke induced functional and transcriptional responses that overlapped with tobacco smoke. Ontology and pathway analysis revealed that cannabis smoke induced DNA replication and oxidative stress responses. Functionally, cannabis smoke impaired epithelial cell barrier function, antiviral responses, and increased inflammatory mediator production. Our study reveals striking similarities between cannabis and tobacco smoke exposure on impairing barrier function, suppressing antiviral pathways, potentiating of pro-inflammatory mediators, and inducing oncogenic and oxidative stress gene expression signatures. Collectively our data suggest that cannabis smoke exposure is not innocuous and may possess many of the deleterious properties of tobacco smoke, warranting additional studies to support public policy, government regulations, and user practices.

Epithelial cell dysfunction, a major driver of asthma development

Airway epithelial barrier dysfunction is frequently observed in asthma and may have important implications. The physical barrier function of the airway epithelium is tightly interwoven with its immunomodulatory actions, while abnormal epithelial repair responses may contribute to remodelling of the airway wall. We propose that abnormalities in the airway epithelial barrier play a crucial role in the sensitization to allergens and pathogenesis of asthma. Many of the identified susceptibility genes for asthma are expressed in the airway epithelium, supporting the notion that events at the airway epithelial surface are critical for the development of the disease. However, the exact mechanisms by which the expression of epithelial susceptibility genes translates into a functionally altered response to environmental risk factors of asthma are still unknown. Interactions between genetic factors and epigenetic regulatory mechanisms may be crucial for asthma susceptibility. Understanding these mechanisms may lead to identification of novel targets for asthma intervention by targeting the airway epithelium. Moreover, exciting new insights have come from recent studies using single‐cell RNA sequencing (scRNA‐Seq) to study the airway epithelium in asthma. This review focuses on the role of airway epithelial barrier function in the susceptibility to develop asthma and novel insights in the modulation of epithelial cell dysfunction in asthma.

tPA promotes the proliferation of lung fibroblasts and activates the Wnt/β-catenin signaling pathway in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible and the most common fatal interstitial lung disease, which is characterized by damaged alveolar structure, the massive proliferation of fibroblasts and deposition of extracellular matrix (ECM). While the pathogenesis of IPF remains unclear, it has been clearly established that the excessive proliferation of lung fibroblasts is the most direct cause of fibrogenesis. Numerous proliferating fibroblasts form fibrous foci and secrete a large amount of ECM to aggravate the process of pulmonary fibrosis. Tissue plasminogen activator (tPA) is a kind of serine protease, its main function is to activate zymogens into active enzymes involved in fibrinolysis. Our study found tPA functioned as a cytokine to promote the proliferation of lung fibroblasts through intracellular signaling events involving Erk1/2, p90RSK, GSK-3β phosphorylation, and cyclinD1 induction. We also uncovered that tPA indirectly activated the Wnt/β-catenin signaling pathway by regulating the GSK-3β phosphorylation level. It's well-known that Wnt/β-catenin signaling pathway plays an important role in the pathogenesis of pulmonary fibrosis, in which the accumulation of β-catenin in the cytoplasm is an important signal of the activation of Wnt/β-catenin signaling pathway. Our study unveiled that tPA can serve as a cytokine involved in Wnt/β-catenin signaling pathway and be implicated in pulmonary fibrosis.

Glucocorticoids inhibits the repair of airway epithelial cells via the activation of wnt pathway

BACKGROUND

The purpose of this study was to explore the effect of Wnt pathway on the inhibition of airway epithelial cells repair by glucocorticoid.

MATERIALS AND METHODS

The expression of E-cadherin in asthma mice model was detected by immunocytochemistry. XAV939 was used to treat 16HBE, and the expressions of related genes were determined by western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability, migration and cell cycle were analyzed by methylthiazolyldiphenyl-tetrazolium bromide, wound healing and flow cytometry, respectively.

RESULTS

In asthma mice model, the lung tissue was impaired. After dexamethasone treatment, the airway inflammation was relieved and the expression of E-cadherin was reduced. Dexamethasone increased the expressions of Wnt7b, LRP5, β-catenin and CyclinD1, inhibited cell viability and migration and arrested cell cycle, whereas XAV939 produced the opposite effects. In addition, XAV939 suppressed Wnt pathway that activated by dexamethasone.

CONCLUSION

Glucocorticoid could inhibit cell proliferation and migration via regulating Wnt pathway to affect cell cycle, thus inhibiting the repair of airway epithelial after injury.

Chronic Obstructive Pulmonary Disease and Lung Cancer: Underlying Pathophysiology and New Therapeutic Modalities

Chronic obstructive pulmonary disease (COPD) and lung cancer are major lung diseases affecting millions worldwide. Both diseases have links to cigarette smoking and exert a considerable societal burden. People suffering from COPD are at higher risk of developing lung cancer than those without, and are more susceptible to poor outcomes after diagnosis and treatment. Lung cancer and COPD are closely associated, possibly sharing common traits such as an underlying genetic predisposition, epithelial and endothelial cell plasticity, dysfunctional inflammatory mechanisms including the deposition of excessive extracellular matrix, angiogenesis, susceptibility to DNA damage and cellular mutagenesis. In fact, COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution. In the early stages of smoking, body defences provide a combative immune/oxidative response and DNA repair mechanisms are likely to subdue these changes to a certain extent; however, in patients with COPD with lung cancer the consequences could be devastating, potentially contributing to slower postoperative recovery after lung resection and increased resistance to radiotherapy and chemotherapy. Vital to the development of new-targeted therapies is an in-depth understanding of various molecular mechanisms that are associated with both pathologies. In this comprehensive review, we provide a detailed overview of possible underlying factors that link COPD and lung cancer, and current therapeutic advances from both human and preclinical animal models that can effectively mitigate this unholy relationship.

Epithelial-mesenchymal transition is driven by transcriptional and post transcriptional modulations in COPD: implications for disease progression and new therapeutics

COPD is a common and highly destructive disease with huge impacts on people and health services throughout the world. It is mainly caused by cigarette smoking though environmental pollution is also significant. There are no current treatments that affect the overall course of COPD; current drugs focus on symptomatic relief and to some extent reducing exacerbation rates. There is an urgent need for in-depth studies of the fundamental pathogenic mechanisms that underpin COPD. This is vital, given the fact that nearly 40%-60% of the small airway and alveolar damage occurs in COPD well before the first measurable changes in lung function are detected. These individuals are also at a high risk of lung cancer. Current COPD research is mostly centered around late disease and/or innate immune activation within the airway lumen, but the actual damage to the airway wall has early onset. COPD is the end result of complex mechanisms, possibly triggered through initial epithelial activation. To change the disease trajectory, it is crucial to understand the mechanisms in the epithelium that are switched on early in smokers. One such mechanism we believe is the process of epithelial to mesenchymal transition. This article highlights the importance of this profound epithelial cell plasticity in COPD and also its regulation. We consider that understanding early changes in COPD will open new windows for therapy.

Effects of aminophylline on airway epithelial-mesenchymal transition in brown Norway rats after repeated allergen challenge

Purpose: Chronic asthma is characterized by airway inflammation and remodeling. The aim of this study is to evaluate the effects of aminophylline on airway epithelial-mesenchymal transition (EMT). Materials and methods: Two experimental groups of brown Norway rats that were repeatedly challenged with aerosolized ovalbumin (OA) were given oral aminophylline (OA-aminophylline group) or saline only (OA-saline group). A third group was challenged by saline as a control. The rats were anesthetized and pulmonary function were performed. Immuno-histochemical staining of epithelial markers (zonula occludens-1 (ZO-1)) and mesenchymal markers (vimentin) in the airway were performed. The protein expressions of ZO-1, E-cadherin, vimentin, fibronectine, TGF-ß1, SMAD 2/3, JNK, and p38 MAPK were examined by western blot. Results: Aminophylline had beneficial effects on airway inflammation, and airway remodeling in the OA-aminophylline group compared to the OA-saline group. The OA-saline group had decreased ZO-1 but increased vimentin according to immuno-histochemical staining. The protein expression indicated decreases in ZO-1 and E-cadherin but increases in vimentin, fibronectine, TGF-ß1, SMAD 2/3, JNK, and p38 MAPK in comparison to the other two groups. The OA-aminophylline group had higher ZO-1 but lower vimentin in immuno-histochemical staining compared to the OA-saline group. The protein expression showed higher ZO-1 and E-cadherin but lower vimentin, fibronectine, TGF-ß1, SMAD 2/3, JNK, and p38 MAPK when compared to the OA-saline group. Conclusions: Ovalbumin increases airway remodeling and airway EMT. Aminophylline is effective in preventing airway remodeling and airway EMT in Brown Norway rats after repeated allergen challenge.

Regulation of Human Airway Epithelial Tissue Stem Cell Differentiation by β-Catenin, P300, and CBP

The wingless/integrase-1 (WNT)/β-catenin signaling pathway is active in several chronic lung diseases including idiopathic pulmonary fibrosis, asthma, and chronic obstructive pulmonary disease. Although this WNT/β-catenin pathway activity is associated with an increase in mucus cell frequency and a decrease in ciliated cell frequency, a cause and consequence relationship between signaling and cell frequency has not been established. We previously demonstrated that genetic stabilization of β-catenin inhibited differentiation of mouse bronchiolar tissue stem cells (TSC). This study determined the effect of β-catenin and its co-factors P300 (E1A-binding protein, 300 kDa) and cAMP response element binding (CREB)-binding protein (CBP) on human bronchial epithelial TSC differentiation to mucus and ciliated cells. We developed a modified air-liquid interface (ALI) culture system in which mucus and ciliated cell frequency is similar. These cultures were treated with the β-catenin agonist CHIR99021 (CHIR) and antagonists to β-catenin (XAV939), P300 (IQ1), and CBP (ICG001). We report that human TSC differentiation to mucus and ciliated cells can be divided into two stages, specification and commitment. CHIR treatment inhibited mucus and ciliated cell commitment while XAV939 treatment demonstrated that β-catenin was necessary for mucus and ciliated cell specification. Additional studies demonstrate that a β-catenin/P300 complex promotes mucus cell specification and that β-catenin interacts with either P300 or CBP to inhibit ciliated cell commitment. These data indicate that activation of β-catenin-dependent signaling in chronic lung disease leads to changes in mucus and ciliated cell frequency and that P300 and CBP tune the β-catenin signal to favor mucus cell differentiation. Stem Cells 2018;36:1905-12.

RAGE mediates β-catenin stabilization via activation of the Src/p-Cav-1 axis in a chemical-induced asthma model

We previously demonstrated receptor for advanced glycation end products (RAGE) was required for β-catenin stabilization in a toluene diisocyanate (TDI)-induced asthma model, suggesting it plays an important role in TDI-induced airway inflammation. The aim of this study was to examine whether RAGE mediates β-catenin stabilization via activation of the Src/p-Cav-1 axis in TDI-induced asthma model. To generate a chemical-induced asthma model, male BALB/c mice were sensitized and challenged with TDI. Before each challenge, FPS-ZM1 (RAGE inhibitor) and PP2 (Src inhibitor) was given via intraperitoneal injection. In the TDI-exposed mice, airway reactivity, airway inflammation, goblet cell metaplasia, and the release of Th2 cytokines and IgE increased significantly. The level of membrane β-catenin decreased but was increased in the cytoplasm. Increased expression of RAGE, p-Src, and p-Cav-1 was also detected in TDI-exposed lungs. However, all these changes were inhibited by FPS-ZM1 and PP2. In TDI-HSA stimulated human airway epithelial (16HBE) cells, the expression of p-Src and p-Cav-1, and the abnormal distribution of β-catenin were significantly increased, and then inhibited in RAGE knockdown cells. Similarly, PP2 or non-phosphorylatable Cav-1 mutant (Y14F-Cav-1) treated 16HBE cells had the same effect on the distribution of β-catenin. In addition, blockage of RAGE signaling and phosphorylation of Cav-1 eliminated the translocation of β-catenin from cytomembrane to cytoplasm. Our results showed that RAGE modulates β-catenin aberrant distribution via activation of Src/p-Cav-1 in a chemical-induced asthma model.

Inhibition of Wnt/β-catenin signaling suppresses myofibroblast differentiation of lung resident mesenchymal stem cells and pulmonary fibrosis

An emerging paradigm proposes a crucial role for lung resident mesenchymal stem cells (LR-MSCs) via a fibroblastic transdifferentiation event in the pathogenesis of idiopathic pulmonary fibrosis (IPF). Aberrant activation of Wnt/β-catenin signaling occurs in virtually all fibrotic lung diseases and is relevant to the differentiation of mesenchymal stem cells (MSCs). In vitro, by measuring the protein levels of several key components involved in Wnt/β-catenin signaling, we confirmed that this signaling pathway was activated in the myofibroblast differentiation of LR-MSCs. Targeted inhibition of Wnt/β-catenin signaling by a small molecule, ICG-001, dose-dependently impeded the proliferation and transforming growth factor-β1 (TGF-β1)-mediated fibrogenic actions of LR-MSCs. In vivo, ICG-001 exerted its lung protective effects after bleomycin treatment through blocking mesenchymal-myofibroblast transition, repressing matrix gene expression, and reducing cell apoptosis. Moreover, delayed administration of ICG-001 attenuated bleomycin-induced lung fibrosis, which may present a promising therapeutic strategy for intervention of IPF. Interestingly, these antifibrotic actions of ICG-001 are operated by a mechanism independent of any disruption of Smad activation. In conclusion, our study demonstrated that Wnt/β-catenin signaling may be an essential mechanism underlying the regulation of myofibroblast differentiation of LR-MSCs and their further participation in the development of pulmonary fibrosis.

Inhibition of Wnt/β-catenin signaling suppresses myofibroblast differentiation of lung resident mesenchymal stem cells and pulmonary fibrosis

An emerging paradigm proposes a crucial role for lung resident mesenchymal stem cells (LR-MSCs) via a fibroblastic transdifferentiation event in the pathogenesis of idiopathic pulmonary fibrosis (IPF). Aberrant activation of Wnt/β-catenin signaling occurs in virtually all fibrotic lung diseases and is relevant to the differentiation of mesenchymal stem cells (MSCs). In vitro, by measuring the protein levels of several key components involved in Wnt/β-catenin signaling, we confirmed that this signaling pathway was activated in the myofibroblast differentiation of LR-MSCs. Targeted inhibition of Wnt/β-catenin signaling by a small molecule, ICG-001, dose-dependently impeded the proliferation and transforming growth factor-β1 (TGF-β1)-mediated fibrogenic actions of LR-MSCs. In vivo, ICG-001 exerted its lung protective effects after bleomycin treatment through blocking mesenchymal-myofibroblast transition, repressing matrix gene expression, and reducing cell apoptosis. Moreover, delayed administration of ICG-001 attenuated bleomycin-induced lung fibrosis, which may present a promising therapeutic strategy for intervention of IPF. Interestingly, these antifibrotic actions of ICG-001 are operated by a mechanism independent of any disruption of Smad activation. In conclusion, our study demonstrated that Wnt/β-catenin signaling may be an essential mechanism underlying the regulation of myofibroblast differentiation of LR-MSCs and their further participation in the development of pulmonary fibrosis.

Influenza A virus infection dysregulates the expression of microRNA-22 and its targets; CD147 and HDAC4, in epithelium of asthmatics

Background

Specific microRNAs (miRNAs) play essential roles in airway remodeling in asthma. Infection with influenza A virus (IAV) may also magnify pre-existing airway remodeling leading to asthma exacerbation. However, these events remain to be fully defined. We investigated the expression of miRNAs with diverse functions including proliferation (miR-20a), differentiation (miR-22) or innate/adaptive immune responses (miR-132) in primary bronchial epithelial cells (pBECs) of asthmatics following infection with the H1N1 strain of IAV.

Methods

pBECs from subjects (n = 5) with severe asthma and non-asthmatics were cultured as submerged monolayers or at the air-liquid-interface (ALI) conditions and incubated with IAV H1N1 (MOI 5) for up to 24 h. Isolated miRNAs were subjected to Taqman miRNAs assays. We confirmed miRNA targets using a specific mimic and antagomir. Taqman mRNAs assays and immunoblotting were used to assess expression of target genes and proteins, respectively.

Results

At baseline, these miRNAs were expressed at the same level in pBECs of asthmatics and non-asthmatics. After 24 h of infection, miR-22 expression increased significantly which was associated with the suppression of CD147 mRNA and HDAC4 mRNA and protein expression in pBECs from non-asthmatics, cultured in ALI. In contrast, miR-22 remained unchanged while CD147 expression increased and HDAC4 remained unaffected in cells from asthmatics. IAV H1N1 mediated increases in SP1 and c-Myc transcription factors may underpin the induction of CD147 in asthmatics.

Conclusion

The different profile of miR-22 expression in differentiated epithelial cells from non-asthmatics may indicate a self-defense mechanism against aberrant epithelial responses through suppressing CD147 and HDAC4, which is compromised in epithelial cells of asthmatics.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0851-7) contains supplementary material, which is available to authorized users.

Identification of Differentially Expressed Genes between Original Breast Cancer and Xenograft Using Machine Learning Algorithms

Breast cancer is one of the most common malignancies in women. Patient-derived tumor xenograft (PDX) model is a cutting-edge approach for drug research on breast cancer. However, PDX still exhibits differences from original human tumors, thereby challenging the molecular understanding of tumorigenesis. In particular, gene expression changes after tissues are transplanted from human to mouse model. In this study, we propose a novel computational method by incorporating several machine learning algorithms, including Monte Carlo feature selection (MCFS), random forest (RF), and rough set-based rule learning, to identify genes with significant expression differences between PDX and original human tumors. First, 831 breast tumors, including 657 PDX and 174 human tumors, were collected. Based on MCFS and RF, 32 genes were then identified to be informative for the prediction of PDX and human tumors and can be used to construct a prediction model. The prediction model exhibits a Matthews coefficient correlation value of 0.777. Seven interpretable interactions within the informative gene were detected based on the rough set-based rule learning. Furthermore, the seven interpretable interactions can be well supported by previous experimental studies. Our study not only presents a method for identifying informative genes with differential expression but also provides insights into the mechanism through which gene expression changes after being transplanted from human tumor into mouse model. This work would be helpful for research and drug development for breast cancer.

Interleukin-37 alleviates airway inflammation and remodeling in asthma via inhibiting the activation of NF-κB and STAT3 signalings

Asthma is a common respiratory inflammatory disorder disease of childhood, and airway smooth muscle cells (ASMCs) play an important role in this disease. Recently, studies have found that interleukin (IL)-37 inhibits allergic airway inflammation of asthmatic mouse models. The aim of this study was to investigate the exact mechanism of IL-37 in asthma. In this study, we found recombinant human IL-37 protein significantly reduced ovalbumin (OVA)-induced airway hyperresponsiveness, inflammatory cell infiltration, the epithelial-mesenchymal-transition (EMT) process, and levels of IL-4, IL-6 and IL-13, but increased interferon (IFN)-γ expression. Moreover, IL-37 treatment remarkably inhibited transforming growth factor (TGF)-β1-induced cell proliferation, migration, EMT, and inflammatory response in ASMCs. IL-37 notably upregulated IκB expression and downregulated levels of NF-κB p65, phospho-NF-κB p65, STAT3 and phospho-STAT3 both in OVA-induced mice and in TGF-β1-stimulated ASMCs. The effects of IL-37 on TGF-β1-induced ASMCs were abrogated by STAT3 upregulation. Additionally, PDTC, a NF-κB inhibitor, showed the similar effects as IL-37 in ASMCs. In conclusion, IL-37 may alleviate airway inflammation and remodeling in asthma through suppressing the activation of NF-κB and STAT3.

Conditionally reprogrammed primary airway epithelial cells maintain morphology, lineage and disease specific functional characteristics

Current limitations to primary cell expansion led us to test whether airway epithelial cells derived from healthy children and those with asthma and cystic fibrosis (CF), co-cultured with an irradiated fibroblast feeder cell in F-medium containing 10 µM ROCK inhibitor could maintain their lineage during expansion and whether this is influenced by underlying disease status. Here, we show that conditionally reprogrammed airway epithelial cells (CRAECs) can be established from both healthy and diseased phenotypes. CRAECs can be expanded, cryopreserved and maintain phenotypes over at least 5 passages. Population doublings of CRAEC cultures were significantly greater than standard cultures, but maintained their lineage characteristics. CRAECs from all phenotypes were also capable of fully differentiating at air-liquid interface (ALI) and maintained disease specific characteristics including; defective CFTR channel function cultures and the inability to repair wounds. Our findings indicate that CRAECs derived from children maintain lineage, phenotypic and importantly disease-specific functional characteristics over a specified passage range.

Lung development, regeneration and plasticity: From disease physiopathology to drug design using induced pluripotent stem cells

Lungs have a complex structure composed of different cell types that form approximately 17 million airway branches of gas-delivering bronchioles connected to 500 million gas-exchanging alveoli. Airways and alveoli are lined by epithelial cells that display a low rate of turnover at steady-state, but can regenerate the epithelium in response to injuries. Here, we review the key points of lung development, homeostasis and epithelial cell plasticity in response to injury and disease, because this knowledge is required to develop new lung disease treatments. Of note, canonical signaling pathways that are essential for proper lung development during embryogenesis are also involved in the pathophysiology of most chronic airway diseases. Moreover, the perfect control of these interconnected pathways is needed for the successful differentiation of induced pluripotent stem cells (iPSC) into lung cells. Indeed, differentiation of iPSC into airway epithelium and alveoli is based on the use of biomimetics of normal embryonic and fetal lung development. In vitro iPSC-based models of lung diseases can help us to better understand the impaired lung repair capacity and to identify new therapeutic targets and new approaches, such as lung cell therapy.

Pluripotent stem cell differentiation reveals distinct developmental pathways regulating lung- versus thyroid-lineage specification

The in vitro-directed differentiation of pluripotent stem cells (PSCs) through stimulation of developmental signaling pathways can generate mature somatic cell types for basic laboratory studies or regenerative therapies. However, there has been significant uncertainty regarding a method to separately derive lung versus thyroid epithelial lineages, as these two cell types each originate from Nkx2-1⁺ foregut progenitors and the minimal pathways claimed to regulate their distinct lineage specification in vivo or in vitro have varied in previous reports. Here, we employ PSCs to identify the key minimal signaling pathways (Wnt+BMP versus BMP+FGF) that regulate distinct lung- versus thyroid-lineage specification, respectively, from foregut endoderm. In contrast to most previous reports, these minimal pathways appear to be evolutionarily conserved between mice and humans, and FGF signaling, although required for thyroid specification, unexpectedly appears to be dispensable for lung specification. Once specified, distinct Nkx2-1⁺ lung or thyroid progenitor pools can now be independently derived for functional 3D culture maturation, basic developmental studies or future regenerative therapies.

ZEB1 Mediates Drug Resistance and EMT in p300-Deficient CRC

We discuss the hypothesis that ZEB1-Wnt-p300 signaling integrates epithelial to mesenchymal transition (EMT) and resistance to histone deacetylase inhibitors (HDACis) in colorectal cancer (CRC) cells. The HDACi butyrate, derived from dietary fiber, has been linked to CRC prevention, and other HDACis have been proposed as therapeutic agents against CRC. We have previously discussed that resistance to butyrate likely contributes to colonic carcinogenesis, and we have demonstrated that butyrate resistance leads to cross-resistance to cancer therapeutic HDACis. Deregulated Wnt signaling is the major initiating event in most CRC cases. One mechanism whereby butyrate and other HDACis exert their anti-CRC effects is via Wnt signaling hyperactivation, which promotes CRC cell apoptosis. The histone acetylases (HATs) CBP and p300 are mediators of Wnt transcriptional activity, and play divergent roles in the downstream consequences of Wnt signaling. CBP-mediated Wnt signaling is associated with cell proliferation and stem cell maintenance; whereas, p300-mediated Wnt activity is associated with differentiation. We have found that CBP and p300 differentially affect the ability of butyrate to influence Wnt signaling, apoptosis, and proliferation. ZEB1 is a Wnt signaling-targeted gene, whose product is a transcription factor expressed at the invasive front of carcinomas where it promotes malignant progression and EMT. ZEB1 is typically a transcriptional repressor; however, when associated with p300, ZEB1 enhances transcription. These changes in ZEB1 activity likely affect the cancer cell phenotype. ZEB1 has been shown to promote resistance to chemotherapeutic agents, and expression of ZEB1 is upregulated in butyrate-resistant CRC cells that lack p300 expression. Since the expression of ZEB1 correlates with poor outcomes in cancer, ZEB represents a relevant therapeutic target. Here we propose that targeting the signaling network established by ZEB1, Wnt signaling, and p300 signaling can reverse HDACi resistance and inhibit EMT.

Blockade of β-catenin signaling attenuates toluene diisocyanate-induced experimental asthma

BACKGROUND

Aberrant activation of β-catenin signaling by both WNT-dependent and WNT-independent pathways has been demonstrated in asthmatic airways, which is thought to contribute critically in remodeling of the airways. Yet, the exact role of β-catenin in asthma is very poorly defined. As we have previously reported abnormal expression of β-catenin in a toluene diisocyanate (TDI)-induced asthma model, in this study, we evaluated the therapeutic efficacy of two small molecules XAV-939 and ICG-001 in TDI-asthmatic male BALB/c mice, which selectively block β-catenin-mediated transcription.

METHODS

Male BALB/c mice were sensitized and challenged with TDI to generate a chemically induced asthma model. Inhibitors of β-catenin, XAV-939, and ICG-001 were respectively given to the mice through intraperitoneally injection.

RESULTS

TDI exposure led to a significantly increased activity of β-catenin, which was then confirmed by a luciferase assay in 16HBE transfected with the TOPFlash reporter plasmid. Treatment with either XAV-939 or ICG-001 effectively inhibited activation of β-catenin and downregulated mRNA expression of β-catenin-targeted genes in TDI-asthmatic mice, paralleled by dramatically attenuated TDI-induced hyperresponsiveness and inflammation of the airway, alleviated airway goblet cell metaplasia and collagen deposition, decreased Th2 inflammation, as well as lower levels of TGFβ1, VEGF, HMGB1, and IL-1β.

CONCLUSION

The results showed that β-catenin is a principal mediator of TDI-induced asthma, proposing β-catenin as a promising therapeutic target in asthma.

Epigenetic modifying enzyme expression in asthmatic airway epithelial cells and fibroblasts

BACKGROUND

Recognition of the airway epithelium as a central mediator in the pathogenesis of asthma has necessitated greater understanding of the aberrant cellular mechanisms of the epithelium in asthma. The architecture of chromatin is integral to the regulation of gene expression and is determined by modifications to the surrounding histones and DNA. The acetylation, methylation, phosphorylation, and ubiquitination of histone tail residues has the potential to greatly alter the accessibility of DNA to the cells transcriptional machinery. DNA methylation can also interrupt binding of transcription factors and recruit chromatin remodelers resulting in general gene silencing. Although previous studies have found numerous irregularities in the expression of genes involved in asthma, the contribution of epigenetic regulation of these genes is less well known. We propose that the gene expression of epigenetic modifying enzymes is cell-specific and influenced by asthma status in tissues derived from the airways.

METHODS

Airway epithelial cells (AECs) isolated by pronase digestion or endobronchial brushings and airway fibroblasts obtained by outgrowth technique from healthy and asthmatic donors were maintained in monolayer culture. RNA was analyzed for the expression of 82 epigenetic enzymes across 5 families of epigenetic modifying enzymes. Western blot and immunohistochemistry were also used to examine expression of 3 genes.

RESULTS

Between AECs and airway fibroblasts, we identified cell-specific gene expression in each of the families of epigenetic modifying enzymes; specifically 24 of the 82 genes analyzed showed differential expression. We found that 6 histone modifiers in AECs and one in fibroblasts were differentially expressed in cells from asthmatic compared to healthy donors however, not all passed correction. In addition, we identified a corresponding increase in Aurora Kinase A (AURKA) protein expression in epithelial cells from asthmatics compared to those from non-asthmatics.

CONCLUSIONS

In summary, we have identified cell-specific variation in gene expression in each of the families of epigenetic modifying enzymes in airway epithelial cells and airway fibroblasts. These data provide insight into the cell-specific variation in epigenetic regulation which may be relevant to cell fate and function, and disease susceptibility.

The genetic and epigenetic landscapes of the epithelium in asthma

Asthma is a global health problem with increasing prevalence. The airway epithelium is the initial barrier against inhaled noxious agents or aeroallergens. In asthma, the airway epithelium suffers from structural and functional abnormalities and as such, is more susceptible to normally innocuous environmental stimuli. The epithelial structural and functional impairments are now recognised as a significant contributing factor to asthma pathogenesis. Both genetic and environmental risk factors play important roles in the development of asthma with an increasing number of genes associated with asthma susceptibility being expressed in airway epithelium. Epigenetic factors that regulate airway epithelial structure and function are also an attractive area for assessment of susceptibility to asthma. In this review we provide a comprehensive discussion on genetic factors; from using linkage designs and candidate gene association studies to genome-wide association studies and whole genome sequencing, and epigenetic factors; DNA methylation, histone modifications, and non-coding RNAs (especially microRNAs), in airway epithelial cells that are functionally associated with asthma pathogenesis. Our aims were to introduce potential predictors or therapeutic targets for asthma in airway epithelium. Overall, we found very small overlap in asthma susceptibility genes identified with different technologies. Some potential biomarkers are IRAKM, PCDH1, ORMDL3/GSDMB, IL-33, CDHR3 and CST1 in airway epithelial cells. Recent studies on epigenetic regulatory factors have further provided novel insights to the field, particularly their effect on regulation of some of the asthma susceptibility genes (e.g. methylation of ADAM33). Among the epigenetic regulatory mechanisms, microRNA networks have been shown to regulate a major portion of post-transcriptional gene regulation. Particularly, miR-19a may have some therapeutic potential.

The receptor for advanced glycation end products is required for β-catenin stabilization in a chemical-induced asthma model

BACKGROUND AND PURPOSE

Cytoplasmic retention of β-catenin will lead to its nuclear translocation and subsequent interaction with the transcription factor TCF/LEF that regulates target gene expression. We have previously demonstrated aberrant expression of β-catenin in a model of asthma induced by toluene diisocyanate (TDI). The aim of this study was to examine whether the receptor for advanced glycation end products (RAGE) can regulate β-catenin expression in TDI-induced asthma.

EXPERIMENTAL APPROACH

Male BALB/c mice were sensitized and challenged with TDI to generate a chemically-induced asthma model. Inhibitors of RAGE, FPS-ZM1 and the RAGE antagonist peptide (RAP), were injected i.p. after each challenge. Airway resistance was measured in vivo and bronchoalveolar lavage fluid was analysed. Lungs were examined by histology and immunohistochemistry. Western blotting and quantitative PCR were also used.

KEY RESULTS

Expression of RAGE and of its ligands HMGB1, S100A12, S100B, HSP70 was increased in TDI-exposed lungs. These increases were inhibited by FPS-ZM1 or RAP. Either antagonist blunted airway reactivity, airway inflammation and goblet cell metaplasia, and decreased release of Th2 cytokines. TDI exposure decreased level of membrane β-catenin, phosphorylated Akt (Ser(473) ), inactivated GSK3β (Ser(9) ), dephosphorylated β-catenin at Ser(33) /(37) /Thr(41) , which controls its cytoplasmic degradation, increased phosphorylated β-catenin at Ser(552) , raised cytoplasmic and nuclear levels of β-catenin and up-regulated its targeted gene expression (MMP2, MMP7, MMP9, VEGF, cyclin D1, fibronectin), all of which were reversed by RAGE inhibition.

CONCLUSION AND IMPLICATIONS

RAGE was required for stabilization of β-catenin in TDI-induced asthma, identifying protective effects of RAGE blockade in this model.

Aberrant lysine acetylation in tumorigenesis: Implications in the development of therapeutics

The 'language' of covalent histone modifications translates environmental and cellular cues into gene expression. This vast array of post-translational modifications on histones are more than just covalent moieties added onto a protein, as they also form a platform on which crucial cellular signals are relayed. The reversible lysine acetylation has emerged as an important post-translational modification of both histone and non-histone proteins, dictating numerous epigenetic programs within a cell. Thus, understanding the complex biology of lysine acetylation and its regulators is essential for the development of epigenetic therapeutics. In this review, we will attempt to address the complexities of lysine acetylation in the context of tumorigenesis, their role in cancer progression and emphasize on the modalities developed to target lysine acetyltransferases towards cancer treatment.