Multitranscriptome analyses of keloid fibroblasts reveal the role of the HIF-1α/HOXC6/ERK axis in keloid development

CD147 inhibition reduced fibronectin expression in TGF-β1-induced keloid fibroblasts by targeting Smad2 signaling pathway

BACKGROUND

CD147 is closely involved in the progression of fibrosis and tumor formation in various tissues, however, its role in keloid formation remains unknown. In this study, we investigate the expression of CD147 in keloids and explore its functional roles.

METHODS

CD147 expression in human keloid tissues was assessed using immunohistopathology and western blot analysis. Human keloid fibroblasts (KFs) were cultured and treated with TGF-β1 alone or in combination with the CD147 inhibitor AC-73. Western blot and immunofluorescence were employed to examine CD147 and fibronectin expression levels in KFs post-treatment. Additionally, the effect of CD147 inhibitor on Smad2 phosphorylation and fibronectin protein levels in TGF-β1-induced KFs was evaluated by western blot. Finally, a keloid-bearing nude mouse model was established to investigate the therapeutic effect of AC-73 in vivo.

RESULTS

CD147 expression was significantly higher in keloid tissues compared to normal skin. TGF-β1 treatment upregulated CD147 and fibronectin expressions in cultured KFs. Inhibition of CD147 with AC-73 reduced the expression levels of both CD147 and fibronectin in KFs. Additionally, AC-73 markedly attenuated TGF-β1-induced fibronectin expression and suppressed Smad2 phosphorylation. In the nude mouse model, AC-73 significantly reduced the gross weight of xenotransplanted keloid tissues.

CONCLUSION

These findings suggest that CD147 is closely involved in keloid progression. Inhibition of CD147 downregulates TGF-β1-induced fibronectin expression in KFs by targeting Smad2 signaling pathway. Thus, CD147 may serve as a promising therapeutic target for keloid treatment.

Multiomics analysis elucidated the role of inflammatory response and bile acid metabolism disturbance in electric shock-induced liver injury in mice

PURPOSE

Organ damage caused by electric shock has attracted great attention. Some animal investigations and clinical cases have suggested that electric shock can induce liver injury. This study aimed to investigate the potential mechanism of liver injury induced by electric shock.

METHODS

Healthy male C57BL/6J mice aged 6-8 weeks were romandly divided into two groups: control group and electric shock group. Mice in the electric shock group were shocked on the top of the skull with an electric baton (20 kV) for 5 sec, while mice in the control group were exposed to only the acoustic and light stimulation produced by the electric baton. The effect of electric shock on liver function was evaluated by histological and biochemical analysis, and a metabolomics and transcriptomics study was performed to investigate how electric shock might induce liver damage. All data of this study were analyzed using a two-tailed unpaired Student's t-test in SPSS 22.0 Statistical Package.

RESULTS

The electric shock group had significantly higher serum aspartate aminotransferase and alanine aminotransferase levels than the control group (p < 0.001), and the shock notably caused cytoplasmic swelling and vacuolization, mild inflammatory cell (mainly macrophages and monocytes) infiltration and acute focal necrosis in hepatocytes (p < 0.001). A total of 47 differential metabolites and 249 differentially expressed genes (DEGs) were detected using metabolomic and transcriptomic analyses. These differential metabolites were significantly enriched in primary bile acid biosynthesis (p < 0.05). Gene ontology functional analysis of the DEGs revealed that electric shock disturbed a key biological process involved in the inflammatory response in the mouse liver, and a significant number of DEGs were enriched in Kyoto Encyclopedia of Genes and Genomes-identified pathways related to inflammation, such as the interleukin-17, tumor necrosis factor and mitogen-activated protein kinase signalling pathway. Transcriptomic and metabolomic analyses revealed that bile acid metabolism disturbance including up-regulation of the taurochenodesoxycholic acid, chenodeoxycholic acid and taurocholic acid, and down-regulation of chenodeoxycholic acid clycine conjugate may contribute to the electric shock-induced inflammatory response.

CONCLUSION

Electric shock can induce liver inflammatory injury through the interleukin-17, tumor necrosis factor, and mitogen-activated protein kinase signaling pathway, and the bile acid metabolism disturbance including up-regulation of the taurochenodesoxycholic acid, chenodeoxycholic acid and taurocholic acid, and down-regulation of chenodeoxycholic acid clycine conjugate may contribute to inflammatory liver injury following electric shock.

A pan-cancer analysis of the oncogenic role of N-acetyltransferase 8 like in human cancer

BACKGROUND

N-Acetyltransferase 8 Like (NAT8L) inhibits natural killer (NK)/T-cell cytotoxicity by impairing the formation of the immunological synapse via N-acetylaspartate (NAA). Existing research has predominantly focused on the metabolic functions of NAT8L, particularly in adipose tissues and myelination in the brain. However, in contrast to other N-acetyltransferases such as NAT1 and NAT2, the role of NAT8L in cancer has been less extensively studied. In this study, we conducted a comprehensive pan-cancer analysis to investigate the carcinogenic role of NAT8L in human cancers.

METHODS

We utilized the standardized TCGA pan-cancer dataset to analyze differential expression, clinical prognosis, gene mutation, immune infiltration, epigenetic modification, tumor stemness, and heterogeneity. Additionally, we evaluated the sensitivity of NAT8L to small molecule drugs using the GDSC and CTRP databases.

RESULTS

In this study, we identified that NAT8L expression was upregulated in 6 cancers and downregulated in 12 compared to normal tissues. We analyzed its prognostic value in 5 tumor types (KIRP, COAD, COADREAD, GBMLGG, LUSC) and found correlations with overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI). Furthermore, NAT8L expression was significantly correlated with levels of most immune checkpoints, immunomodulators, and immune cell infiltration. The mutation frequencies for bladder cancer (BLCA), glioblastoma multiforme and glioma (GBMLGG), lower-grade glioma (LGG), and KIRP were 1.2%, 0.9%, 0.8%, and 0.4%, respectively.

CONCLUSION

Our findings suggest that NAT8L may serve as a potential prognostic marker and therapeutic target across a variety of cancers, particularly in KIRP, COAD, COADREAD, GBMLGG, and lung squamous cell carcinoma (LUSC).

Construction of ceRNA Network and Disease Diagnosis Model for Keloid Based on Tumor Suppressor ERRFI1

The aim of this study is to identify the key biomarker of keloid (KD) with significant diagnostic value and to construct the related competing endogenous RNA (ceRNA) network and disease diagnostic model to provide new ideas for the early diagnosis and prevention of KD. Public databases were used to identify the key gene of KD. Enrichment analysis and immune cell infiltration (ICI) analysis revealed its functional and immune characteristics. Then, a ceRNA network was constructed to explore the potential pathways of it. Random forest (RF) analysis was applied to construct a predictive model for the disease diagnosis of KD. Finally, immunohistochemistry (IHC) and RT-qPCR were used to verify the differential expression of key gene. ERRFI1 was identified as a key biomarker in KD and was lowly expressed in KD. The ceRNA network revealed that H0TAIRM1-has-miR-148a-3p-ERRFI1 may be a potential pathway in KD. Finally, a 2-gene diagnostic prediction model (ERRFI1, HSD3B7) was constructed and externally validated and the results suggested that the model had good diagnostic performance. ERRFI1 is a downregulated gene in KD and is expected to be a promising predictive marker and disease diagnostic gene. ICI may play a role in the progression of KD. The ceRNA network may provide new clues to the potential pathogenesis of KD. Finally, the new KD diagnostic model could be an effective tool for assessing the risk of KD development.

Macrophage plasticity: signaling pathways, tissue repair, and regeneration

Macrophages are versatile immune cells with remarkable plasticity, enabling them to adapt to diverse tissue microenvironments and perform various functions. Traditionally categorized into classically activated (M1) and alternatively activated (M2) phenotypes, recent advances have revealed a spectrum of macrophage activation states that extend beyond this dichotomy. The complex interplay of signaling pathways, transcriptional regulators, and epigenetic modifications orchestrates macrophage polarization, allowing them to respond to various stimuli dynamically. Here, we provide a comprehensive overview of the signaling cascades governing macrophage plasticity, focusing on the roles of Toll-like receptors, signal transducer and activator of transcription proteins, nuclear receptors, and microRNAs. We also discuss the emerging concepts of macrophage metabolic reprogramming and trained immunity, contributing to their functional adaptability. Macrophage plasticity plays a pivotal role in tissue repair and regeneration, with macrophages coordinating inflammation, angiogenesis, and matrix remodeling to restore tissue homeostasis. By harnessing the potential of macrophage plasticity, novel therapeutic strategies targeting macrophage polarization could be developed for various diseases, including chronic wounds, fibrotic disorders, and inflammatory conditions. Ultimately, a deeper understanding of the molecular mechanisms underpinning macrophage plasticity will pave the way for innovative regenerative medicine and tissue engineering approaches.

HOXC6-mediated transcriptional activation of ENO2 promotes oral squamous cell carcinoma progression through the Warburg effect

Oral squamous cell carcinoma (OSCC) requires an in-depth exploration of its molecular mechanisms. The Warburg effect, along with the oncogenes enolase 2 (ENO2) and homeobox C6 (HOXC6), plays a central role in cancer. However, the specific interaction between ENO2 and HOXC6 in driving the Warburg effect and OSCC progression remains poorly understood. Through differential gene expression analysis in head and neck squamous cell carcinomas using Gene Expression Profiling Interactive Analysis, we identified upregulated ENO2 in OSCC. Silencing ENO2 in OSCC cells revealed its involvement in migration, invasion, and aerobic glycolysis of OSCC cells. Further exploration of ENO2's regulatory network identified HOXC6 as a potential transcriptional regulator. Subsequently, HOXC6 was silenced in OSCC cells, and expressions of ENO2 were assessed to validate its relationship with ENO2. Chromatin Immunoprecipitation and luciferase assays were utilized to investigate the direct transcriptional activation of ENO2 by HOXC6. A rescue assay co-overexpressing ENO2 and silencing HOXC6 in OSCC cells affirmed HOXC6's role in ENO2-associated glycolysis. High ENO2 expression in OSCC was validated through quantitative real-time polymerase chain reaction, Western blot, and immunohistochemistry analyses, which correlated with poor patient survival. Functional assays demonstrated that ENO2 silencing inhibited glycolysis and attenuated the aggressiveness of OSCC cells. In vivo studies confirmed the oncogenic role of ENO2 in OSCC growth. Notably, HOXC6 exhibited a positive correlation with ENO2 expression in clinical samples. Mechanistically, HOXC6 was identified as a direct transcriptional activator of ENO2, orchestrating the Warburg effect in OSCC cells. This study reveals the intricate link between HOXC6-mediated ENO2 transcriptional activation and the Warburg effect in OSCC, offering a potential therapeutic target for treating OSCC patients.

Profibrotic Inflammatory Cytokines and Growth Factors Are Predicted as the Key Targets of Uncaria gambir (Hunter) Roxb. in Keloids: An Epistatic and Molecular Simulation Approach

Keloid is characterized as the fibrotic tissue resulting from the increase of fibroblast activity. Uncaria gambir (Hunter) Roxb. possesses bioactive compounds that have potential as antifibrotic agents, while the mechanism of action in keloid has not yet been elucidated. The aim of this study was to investigate the interaction of gambir bioactive compounds with keloid target proteins using an epistatic and molecular simulation approach. The known bioactive compounds of gambir targets and keloid-related protein targets were screened using databases. The network was constructed and analyzed to obtain the core protein targets. The targets were enriched to describe the Gene Ontology (GO) and pathway related to the proteins. Eleven targets were defined as the main targets of gambir bioactive compounds related to keloid disease. Gambiriin C, Isogambirine, and Procyanidin B1 were identified as the most promising compounds with the highest binding energy to transforming growth factor beta 1 (TGFβ1), AKT serine/threonine kinase 1 (AKT1), and matrix metallopeptidase 1 (MMP1) as the target proteins. GO enrichment and pathway analysis found that gambir bioactive compounds may act on keloid-related target proteins to regulate cell proliferation, migration, transcription, and signal transduction activity via profibrotic cytokine and growth factor signaling pathways. This study provides a reference for potential targets, compounds, and pathways to explain the mechanism of gambir against keloid.

Hydrogel Loaded with Components for Therapeutic Applications in Hypertrophic Scars and Keloids

Hypertrophic scars and keloids are common fibroproliferative diseases following injury. Patients with pathologic scars suffer from impaired quality of life and psychological health due to appearance disfiguration, itch, pain, and movement disorders. Recently, the advancement of hydrogels in biomedical fields has brought a variety of novel materials, methods and therapeutic targets for treating hypertrophic scars and keloids, which exhibit broad prospects. This review has summarized current research on hydrogels and loaded components used in preventing and treating hypertrophic scars and keloids. These hydrogels attenuate keloid and hypertrophic scar formation and progression by loading organic chemicals, drugs, or bioactive molecules (such as growth factors, genes, proteins/peptides, and stem cells/exosomes). Among them, smart hydrogels (a very promising method for loading many types of bioactive components) are currently favoured by researchers. In addition, combining hydrogels and current therapy (such as laser or radiation therapy, etc.) could improve the treatment of hypertrophic scars and keloids. Then, the difficulties and limitations of the current research and possible suggestions for improvement are listed. Moreover, we also propose novel strategies for facilitating the construction of target multifunctional hydrogels in the future.

The mechanism and targeted intervention of the HIF-1 pathway in improving atherosclerotic heart's sensitivity to ischemic postconditioning

BACKGROUND

IPoC possesses a preventive effect against IR injury in healthy myocardium, but IPoC's protective effect on atherosclerotic myocardium is controversial. The current investigation aims to determine whether IPoC remains protective in atherosclerotic myocardium subjected to ischemia-reperfusion (IR) injury; to explore the specific mechanisms by which IPoC exerts cardioprotection; to explore whether HIF-1 upregulation combined with IPoC could further the provide cardioprotection; and to gaze at the specific mechanism whereby combined treatment expert the cardioprotection.

METHODS

ApoE-/- mice fed with a high-fat diet (HFD) were used to develop a model of atherosclerosis. The myocardial IR model was induced by occlusion of the left anterior descending (LAD) artery for 45 min, followed by reperfusion for 120 min. The protection of IPoC in both healthy and atherosclerotic myocardium was evaluated by measuring oxidative stress, apoptosis, infarct size, pathology, mitochondrial dysfunction and morphology of myocardium. The specific mechanism by which IPoC exerts cardioprotection in healthy and atherosclerotic myocardium was observed by measuring the expression of proteins involved in HIF-1, APMK and RISK pathways. The effect of HIF-1α overexpression on the cardioprotection by IPoC was observed by intravenous AAV9 -HIF-1α injection.

RESULTS

In healthy ischemic myocardium, IPoC exerted myocardial protective effects (antioxidant, anti-apoptosis, and improved mitochondrial function) through the activation of HIF-1, AMPK and RISK pathways. In atherosclerotic ischemic myocardium, IPoC exerted cardioprotection only through the activation of HIF-1 pathway; however, HIF-1 overexpression combined IPoC restored the activation of AMPK and RISK pathways, thereby further alleviating the myocardial IR injury.

CONCLUSIONS

In the atherosclerotic state, the HIF-1 pathway is the intrinsic mechanism by which IPoC exerts cardioprotective effects. The combination of HIF-1 upregulation and IPoC has a significant effect in reducing myocardial injury, which is worth being promoted and advocated. In addition, HIF-1-AMPK and HIF-1-RISK may be two endogenous cardioprotective signalling pathways with great value, which deserve to be thoroughly investigated in the future.

Therapeutic role of exosomes and conditioned medium in keloid and hypertrophic scar and possible mechanisms

Exosomes, ranging from 40 to 160 nm in diameter, are extracellular lipid bilayer microvesicles that regulate the body's physiological and pathological processes and are secreted by cells that contain proteins, nucleic acids, amino acids and other metabolites. Previous studies suggested that mesenchymal stem cell (MSC)-derived exosomes could either suppress or support keloid and hypertrophic scar progression. Although previous research has identified the potential value of MSC-exosomes in keloid and hypertrophic scar, a comprehensive analysis of different sources of MSC-exosome in keloid and hypertrophic scar is still lacking. This review mainly discusses different insights regarding the roles of MSC-exosomes in keloid and hypertrophic scar treatment and summarizes possible underlying mechanisms.

Roles of the HIF-1α pathway in the development and progression of keloids

Keloids, a pathological scar that is induced by the consequence of aberrant wound healing, is still a major global health concern for its unsatisfactory treatment outcomes. HIF-1α, a main regulator of hypoxia, mainly acts through some proteins or signaling pathways and plays important roles in a variety of biological processes. Accumulating evidence has shown that HIF-1α played a crucial role in the process of keloid formation. In this review, we attempted to summarize the current knowledge on the association between HIF-1α expression and the development and progression of keloids. Through a comprehensive analysis, the molecular mechanisms underlying HIF-1α in keloids were shown to be correlated to the proliferation of fibroblasts, angiogenesis, and collagen deposits. The affected proteins and the signaling pathways were multiple. For instance, HIF-1α was reported to promote keloids formation by enhancing angiogenesis, fibroblast proliferation, and collagen deposition through the activation of periostin PI3K/Akt, TGF-β/Smad and TLR4/MyD88/NF-κB pathway. However, the specific effects of HIF-1α on keloids keloid illnesses in clinical practice is are entirely unclear, and further studies in clinical trials are still warranted. Therefore, an in-depth understanding of the biological mechanisms of HIF-1α in keloid formation is significant to develop promising therapeutic targets for the treatment of keloids in clinical practice.

Evidence of inter- and intra-keloid heterogeneity through analysis of dermal fibroblasts: A new insight in deciphering keloid physiopathology

Keloid scars are hypertrophic and proliferating pathological scars extending beyond the initial lesion and without tendency to regression. Usually, keloids are considered and treated as a single entity but clinical observations suggest heterogeneity in keloid morphologies with distinction of superficial/extensive and nodular entities. Within a keloid, heterogeneity could also be detected between superficial and deep dermis or centre and periphery. Focusing on fibroblasts as main actors of keloid formation, we aimed at evaluating intra- and inter-keloid fibroblast heterogeneity by analysing their gene expression and functional capacities (proliferation, migration, traction forces), in order to improve our understanding of keloid pathogenesis. Fibroblasts were obtained from centre, periphery, papillary and reticular dermis from extensive or nodular keloids and were compared to control fibroblasts from healthy skin. Transcriptional profiling of fibroblasts identified a total of 834 differentially expressed genes between nodular and extensive keloids. Quantification of ECM-associated gene expression by RT-qPCR brought evidence that central reticular fibroblasts of nodular keloids are the population which synthesize higher levels of mature collagens, TGFβ, HIF1α and αSMA as compared to control skin, suggesting that this central deep region is the nucleus of ECM production with a centrifuge extension in keloids. Although no significant variations were found for basal proliferation, migration of peripheral fibroblasts from extensive keloids was higher than that of central ones and from nodular cells. Moreover, these peripheral fibroblasts from extensive keloids exhibited higher traction forces than central cells, control fibroblasts and nodular ones. Altogether, studying fibroblast features demonstrate keloid heterogeneity, leading to a better understanding of keloid pathophysiology and treatment adaptation.