ALKBH5 facilitates the progression of skin cutaneous melanoma via mediating ABCA1 demethylation and modulating autophagy in an m6A-dependent manner.

Background: N6-methyladenosine (m6A) is the most common and abundant mRNA modification, playing an essential role in biological processes and tumor development. However, the role of m6A methylation in skin cutaneous melanoma (SKCM) is not yet clear. This study analyzed the expression of m6A-related functional genes in SKCM and aimed to explore the key demethylase ALKBH5 mediated m6A modification and its potential mechanism in human SKCM. Methods: Based on public databases, the m6A-related gene expression landscape in SKCM was portrayed. MeRIP-Seq and RNA-Seq were used to recognize the downstream target of ALKBH5. In vivo and in vitro functional phenotype and rescue functional experiments were performed to explore the mechanism of the ALKBH5-m6A-ABCA1 axis in SKCM. Results: We found ALKBH5 upregulated in SKCM, associated with poor prognosis. ALKBH5 can promote melanoma cell proliferation, colony formation, migration, and invasion and inhibit autophagy in vitro, facilitating tumor growth and metastasis in vivo. We identified ABCA1, a membrane protein that assists cholesterol efflux, as a downstream target of ALKBH5-mediated m6A demethylation. Finally, our data demonstrated that ALKBH5 promoted SKCM via mediating ABCA1 downregulation by reducing ABCA1 mRNA stability in an m6A-dependent manner. Conclusion: Our findings exhibited the functional value of the key demethylase ALKBH5 mediated m6A modification in the progression of SKCM, suggesting the ALKBH5-m6A-ABCA1 axis as a potential therapeutic target in SKCM.

Programmed microalgae-gel promotes chronic wound healing in diabetes.

Chronic diabetic wounds are at lifelong risk of developing diabetic foot ulcers owing to severe hypoxia, excessive reactive oxygen species (ROS), a complex inflammatory microenvironment, and the potential for bacterial infection. Here we develop a programmed treatment strategy employing live Haematococcus (HEA). By modulating light intensity, HEA can be programmed to perform a variety of functions, such as antibacterial activity, oxygen supply, ROS scavenging, and immune regulation, suggesting its potential for use in programmed therapy. Under high light intensity (658 nm, 0.5 W/cm2), green HEA (GHEA) with efficient photothermal conversion mediate wound surface disinfection. By decreasing the light intensity (658 nm, 0.1 W/cm2), the photosynthetic system of GHEA can continuously produce oxygen, effectively resolving the problems of hypoxia and promoting vascular regeneration. Continuous light irradiation induces astaxanthin (AST) accumulation in HEA cells, resulting in a gradual transformation from a green to red hue (RHEA). RHEA effectively scavenges excess ROS, enhances the expression of intracellular antioxidant enzymes, and directs polarization to M2 macrophages by secreting AST vesicles via exosomes. The living HEA hydrogel can sterilize and enhance cell proliferation and migration and promote neoangiogenesis, which could improve infected diabetic wound healing in female mice.

Inhibition of phosphatidylinositol 3-kinase catalytic subunit alpha by miR-203a-3p reduces hypertrophic scar formation via phosphatidylinositol 3-kinase/AKT/mTOR signaling pathway.

Background: Hypertrophic scar (HS) is a common fibroproliferative skin disease that currently has no truly effective therapy. Given the importance of phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) in hypertrophic scar formation, the development of therapeutic strategies for endogenous inhibitors against PIK3CA is of great interest. Here, we explored the molecular mechanisms underlying the protective effects of miR-203a-3p (PIK3CA inhibitor) against excessive scar. Methods: Bioinformatic analysis, immunohistochemistry, immunofluorescence, miRNA screening and fluorescence in situ hybridization assays were used to identify the possible pathways and target molecules mediating HS formation. A series of in vitro and in vivo experiments were used to clarify the role of PIK3CA and miR-203a-3p in HS. Mechanistically, transcriptomic sequencing, immunoblotting, dual-luciferase assay and rescue experiments were executed. Results: Herein, we found that PIK3CA and the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathway were upregulated in scar tissues and positively correlated with fibrosis. We then identified miR-203a-3p as the most suitable endogenous inhibitor of PIK3CA. miR-203a-3p suppressed the proliferation, migration, collagen synthesis and contractility as well as the transdifferentiation of fibroblasts into myofibroblasts in vitro, and improved the morphology and histology of scars in vivo. Mechanistically, miR-203a-3p attenuated fibrosis by inactivating the PI3K/AKT/mTOR pathway by directly targeting PIK3CA. Conclusions: PIK3CA and the PI3K/AKT/mTOR pathway are actively involved in scar fibrosis and miR-203a-3p might serve as a potential strategy for hypertrophic scar therapy through targeting PIK3CA and inactivating the PI3K/AKT/mTOR pathway.

A nanocomposite hydrogel for co-delivery of multiple anti-biofilm therapeutics to enhance the treatment of bacterial biofilm-related infections.

The characteristics of biofilms have exacerbated the issue of clinical antibiotic resistance, rendering it a pressing challenge in need of resolution. The combination of biofilm-dispersing agents and antibiotics can eliminate biofilms and promote healing synergistically in infected wounds. In this study, we developed a novel nanocomposite hydrogel (NC gel) comprised of the poly(lactic acid)-hyperbranched polyglycerol (PLA-HPG) based bioadhesive nanoparticles (BNPs) and a hydrophilic carboxymethyl chitosan (CS) network. The NC gel was designed to co-deliver two biofilm-dispersing agents (an NO-donor SNO, and an α-amylase Am) and an antibiotic, cefepime (Cef), utilizing a synergistic anti-biofilm mechanism in which Am loosens the matrix structure and NO promotes the release of biofilm bacteria via quorum sensing, and Cef kills bacteria. The drug-loaded NC gel (SNO/BNP/CS@Am-Cef) demonstrated sustained drug release, minimal cytotoxicity, and increased drug-bacterial interactions at the site of infection. When applied to mice infected with methicillin-resistant Staphylococcus aureus (MRSA) biofilms in vivo, SNO/BNP/CS@Am-Cef enhanced biofilm elimination and promoted wound healing compared to traditional antibiotic treatments. Our work demonstrates the feasibility of the co-delivery of biofilm-dispersing agents and antibiotics using the NC gel and presents a promising approach for the polytherapy of bacterial biofilm-related infections.

Novel approach for enhancing skin allograft survival by bioadhesive nanoparticles loaded with rapamycin.

Skin graft rejection is a significant challenge in skin allografts for skin defects, particularly in extensive burn injury patients when autografts are insufficient. Enhancing the survival duration of allogeneic skin grafts can improve the success rate of subsequent autologous skin grafting, thereby promoting the therapeutic efficacy for wound healing. Rapamycin (Rapa), a potent immunosuppressant with favorable efficacy in organ transplantation, is limited by its systemic administration-associated toxicity and side effects. Therefore, addressing the short survival time of allogeneic skin grafts and minimizing the toxicity related to systemic application of immunosuppressive agents is an urgent requirement. Here, we present a topical formulation based on bioadhesive poly (lactic acid)-hyperbranched polyglycerol nanoparticles (BNPs) with surface-modified encapsulation of Rapamycin (Rapa/BNPs), applied for local immunosuppression in a murine model of allogeneic skin grafts. Our Rapa/BNPs significantly prolong nanoparticle retention, reduce infiltration of T lymphocytes and macrophages, decrease the level of pro-inflammatory cytokines and ultimately extend skin allograft survival with little systemic toxicity compared to free Rapa or Rapamycin-loaded non-bioadhesive nanoparticles (Rapa/NNPs) administration. In conclusion, Rapa/BNPs effectively deliver local immunosuppression and demonstrate potential for enhancing skin allograft survival while minimizing localized inflammation, thus potentially increasing patient survival rates for various types of skin defects.

Verteporfin-Loaded Bioadhesive Nanoparticles for the Prevention of Hypertrophic Scar.

Hypertrophic scarring (HS) is a common skin injury complication with unmet needs. Verteporfin (VP) should be an ideal HS-targeted therapeutic drug due to its efficient fibrosis and angiogenesis inhibitory abilities. However, its application is restricted by its side effects such as dose-dependent cytotoxicity on normal cells. Herein, the bioadhesive nanoparticles encapsulated VP (VP/BNPs) are successfully developed to attenuate the side effects of VP and enhance its HS inhibition effects by limiting VP releasing slowly and stably in the lesion site but not diffusing easily to normal tissues. VP/BNPs displayed significant inhibition on the proliferation, migration, collagen deposition, and vessel formation of human hypertrophic scar fibroblasts (HSFBs) and dermal vascular endothelial cells (HDVECs). In a rat tail HS model, VP/BNPs treated HS exhibits dramatic scar repression with almost no side effects compared with free VP or VP-loaded non-bioadhesive nanoparticles (VP/NNPs) administration. Further immunofluorescence analysis on scar tissue serial sections validated VP/BNPs effectively inhibited the collagen deposition and angiogenesis by firmly confined in the scar tissue and persistently releasing VP targeted to nucleus Yes-associated protein (nYAP) of HSFBs and HDVECs. These findings collectively suggest that VP/BNPs can be a promising and technically advantageous agent for HS therapies.

Single-cell profiling reveals transcriptomic signatures of vascular endothelial cells in non-healing diabetic foot ulcers.

Background: The treatment of diabetic foot ulcers (DFUs) poses a challenging medical problem that has long plagued individuals with diabetes. Clinically, wounds that fail to heal for more than 12 weeks after the formation of DFUs are referred to as non-healing/chronic wounds. Among various factors contributing to the non-healing of DFUs, the impairment of skin microvascular endothelial cell function caused by high glucose plays a crucial role. Our study aimed to reveal the transcriptomic signatures of non-healing DFUs endothelial cells, providing novel intervention targets for treatment strategies. Methods: Based on the GEO dataset (GSE165816), we selected DFU-Healer, DFU-Non-healer, and healthy non-diabetic controls as research subjects. Single-cell RNA transcriptomic sequencing technology was employed to analyze the heterogeneity of endothelial cells in different skin tissue samples and identify healing-related endothelial cell subpopulations. Immunofluorescence was applied to validate the sequencing results on clinical specimens. Results: The number of endothelial cells and vascular density showed no significant differences among the three groups of skin specimens. However, endothelial cells from non-healing DFUs exhibited apparent inhibition of angiogenesis, inflammation, and immune-related signaling pathways. The expression of CCND1, ENO1, HIF1α, and SERPINE1 was significantly downregulated at the transcriptomic and histological levels. Further analysis demonstrated that healing-related endothelial cell subpopulations in non-healing DFUs has limited connection with other cell types and weaker differentiation ability. Conclusion: At the single-cell level, we uncovered the molecular and functional specificity of endothelial cells in non-healing DFUs and highlighted the importance of endothelial cell immune-mediated capability in angiogenesis and wound healing. This provides new insights for the treatment of DFUs.

System analysis based on the pyroptosis-related genes identifes GSDMD as a novel therapy target for skin cutaneous melanoma.

BACKGROUND: Skin cutaneous melanoma (SKCM) is the most aggressive skin cancer, accounting for more than 75% mortality rate of skin-related cancers. As a newly identified programmed cell death, pyroptosis has been found to be closely associated with tumor progression. Nevertheless, the prognostic significance of pyroptosis in SKCM remains elusive. METHODS: A total of 469 SKCM samples and 812 normal samples were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. Firstly, differentially expressed pyroptosis-related genes (PRGs) between normal samples and SKCM samples were identified. Secondly, we established a prognostic model based on univariate Cox and LASSO Cox regression analyses, which was validated in the test cohort from GSE65904. Thirdly, a nomogram was used to predict the survival probability of SKCM patients. The R package "pRRophetic" was utilized to identify the drug sensitivity between the low- and high-risk groups. Tumor immune infiltration was evaluated using "immuneeconv" R package. Finally, the function of GSDMD and SB525334 was explored in A375 and A2058 cells. RESULTS: Based on univariate Cox and LASSO regression analyses, we established a prognostic model with identified eight PRGs (AIM2, CASP3, GSDMA, GSDMC, GSDMD, IL18, NLRP3, and NOD2), which was validated in the test cohort. SKCM patients were divided into low- and high-risk groups based on the median of risk score. Kaplan-Meier survival analysis showed that high-risk patients had shorter overall survival than low-risk patients. Additionally, time-dependent ROC curves validated the accuracy of the risk model in predicting the prognosis of SKCM. More importantly, 4 small molecular compounds (SB525334, SR8278, Gemcitabine, AT13387) were identified, which might be potential drugs for patients in different risk groups. Finally, overexpression of GSDMD and SB525334 treatment inhibit the proliferation, migration, and invasion of SKCM cells. CONCLUSION: In this study, we constructed a prognostic model based on PRGs and identified GSDMD as a potential therapeutic target, which provide new insights into SKCM treatment.

Mechanical pressure-induced dedifferentiation of myofibroblasts inhibits scarring via SMYD3/ITGBL1 signaling.

Pressure therapy (PT) is an effective intervention for reducing scarring, but its underlying mechanism remains largely unclear. Here, we demonstrate that human scar-derived myofibroblasts dedifferentiate into normal fibroblasts in response to PT, and we identify how SMYD3/ITGBL1 contributes to the nuclear relay of mechanical signals. In clinical specimens, reductions in SMYD3 and ITGBL1 expression levels are strongly associated with the anti-scarring effects of PT. The integrin ß1/ILK pathway is inhibited in scar-derived myofibroblasts upon PT, leading to decreased TCF-4 and subsequently to reductions in SMYD3 expression, which reduces the levels of H3K4 trimethylation (H3K4me3) and further suppresses ITGBL1 expression, resulting the dedifferentiation of myofibroblasts into fibroblasts. In animal models, blocking SMYD3 expression results in reductions of scarring, mimicking the positive effects of PT. Our results show that SMYD3 and ITGBL1 act as sensors and mediators of mechanical pressure to inhibit the progression of fibrogenesis and provide therapeutic targets for fibrotic diseases.

Collagen scaffolds derived from bovine skin loaded with MSC optimized M1 macrophages remodeling and chronic diabetic wounds healing.

Owing to the persistent inflammatory microenvironment and unsubstantial dermal tissues, chronic diabetic wounds do not heal easily and their recurrence rate is high. Therefore, a dermal substitute that can induce rapid tissue regeneration and inhibit scar formation is urgently required to address this concern. In this study, we established biologically active dermal substitutes (BADS) by combining novel animal tissue-derived collagen dermal-replacement scaffolds (CDRS) and bone marrow mesenchymal stem cells (BMSCs) for the healing and recurrence treatments of chronic diabetic wounds. The collagen scaffolds derived from bovine skin (CBS) displayed good physicochemical properties and superior biocompatibility. CBS loaded with BMSCs (CBS-MCSs) could inhibit M1 macrophage polarization in vitro. Decreased MMP-9 and increased Col3 at the protein level were detected in CBS-MSCs-treated M1 macrophages, which may be attributed to the suppression of the TNF-α/NF-κB signaling pathway (downregulating phospho-IKKα/ß/total IKKα/ß, phospho-IκB/total IκB, and phospho-NFκB/total NFκB) in M1 macrophages. Moreover, CBS-MSCs could benefit the transformation of M1 (downregulating iNOS) to M2 (upregulating CD206) macrophages. Wound-healing evaluations demonstrated that CBS-MSCs regulated the polarization of macrophages and the balance of inflammatory factors (pro-inflammatory: IL-1ß, TNF-α, and MMP-9; anti-inflammatory: IL-10 and TGF-ß3) in db/db mice. Furthermore, CBS-MSCs facilitated the noncontractile and re-epithelialized processes, granulation tissue regeneration, and neovascularization of chronic diabetic wounds. Thus, CBS-MSCs have a potential value for clinical application in promoting the healing of chronic diabetic wounds and preventing the recurrence of ulcers.

Integration of single-cell and bulk transcriptomics reveals immune-related signatures in keloid.

BACKGROUND: Keloid is a pathological dermatological condition that manifests as an overgrowth scar secondary to skin trauma. This study endeavored to excavate immune-related signatures of keloid based on single-cell RNA (scRNA) sequencing data and bulk RNA sequencing data. METHOD: The keloid-relevant scRNA sequencing dataset GSE163973 and bulk RNA sequencing dataset GSE113619 were mined from the GEO database. The "Seurat" R package was utilized for data quality control, cell clustering, and investigation of marker genes of each cell cluster. The "SingleR" package helped match the marker genes of the corresponding cluster to specific cell types. Moreover, the R package "Monocle" was deployed for pseudotemporal ordering analysis, and the "clusterProfiler" was applied for functional and pathway enrichment analysis. The immune-related signatures were then identified, and potential targeted drugs were predicted via the DGIdb database. Verification of the immune-related signatures in clinical validation samples was implemented by RT-qPCR. RESULTS: Totally 23 cell clusters were screened and classified into 10 cell types based on the scRNA sequencing data. The keloid group had a significantly higher endothelial cell proportion than the control group. As enrichment analysis was applied in both differentially expressed genes (DEGs) of scRNA and bulk RNA sequencing data, we found they were enriched in multiple common immune-related pathways and biological processes. Meanwhile, we acquired three immune-related signatures (VCAM1, CALCRL, and HLA-DPB1) by intersecting the above DEGs with immune-related genes (IRGs). Then, we predicted 16 drugs potentially targeting the biomarkers through the DGIdb database. Finally, the outcome of RT-qPCR of clinical validation samples further verified the results. CONCLUSION: In conclusion, we analyzed the cell types and functional differences in the keloid through scRNA and bulk RNA sequencing data. We identified three immune-related signatures (VCAM1, CALCRL, and HLA-DPB1) in keloid, providing a basis for further in-depth investigation of the molecular mechanisms of keloid and exploration of therapeutic targets.

High Expression of TIMELESS Predicts Poor Prognosis: A Potential Therapeutic Target for Skin Cutaneous Melanoma.

Background: Skin cutaneous melanoma (SKCM) is the most lethal skin cancer with an increasing incidence worldwide. The poor prognosis of SKCM urgently requires us to discover prognostic biomarkers for accurate therapy. As a regulator of DNA replication, TIMELESS (TIM) has been found to be highly expressed in various malignancies but rarely reported in SKCM. The objective of this study was to evaluate the relationship between TIM and SKCM tumorigenesis and prognosis. Methods: We obtained RNA sequencing data from TCGA and GTEx to analyze TIM expression and differentially expressed genes (DEGs). Subsequently, GO/KEGG, GSEA, immune cell infiltration analysis, and protein-protein interaction (PPI) network were used to perform the functional enrichment analysis of TIM-related DEGs. Moreover, the receiver operating characteristic (ROC) curves, Cox regression analysis, Kaplan-Meier (K-M) analysis, and nomograms were applied to figure out the clinical significance of TIM in SKCM. In addition, we investigated the relationship between TIM promoter methylation and SKCM prognosis through the UALCAN database. Finally, the immunohistochemical (IHC) results of normal skin and SKCM were analyzed to determine expression differences. Results: TIM was significantly elevated in various malignancies, including SKCM, and high expression of TIM was associated with poor prognosis. Moreover, a total of 402 DEGs were identified between the two distinct TIM expression groups, and functional annotation showed enrichment with positive regulation of cell cycle and classic oncogenic pathways in the high TIM expression phenotype, while keratinization pathways were negatively regulated and enriched. Further analysis showed that TIM was correlated with infiltration of multiple immune cells. Finally, IHC validated the differential expression of TIM in SKCM. Conclusion: TIM might play a pivotal role in tumorigenesis of SKCM and is closely related to its prognosis.

Topical formulation based on disease-specific nanoparticles for single-dose cure of psoriasis.

First-line treatments for mild to moderate psoriasis are typically topical formulations containing corticosteroids, however, the therapeutic efficacy of these formulations is compromised by limited penetration and skin retention. Even more challenging, off-target corticosteroids are known to adversely affect healthy skin, including induction of epidermal and dermal atrophy. Here, we report a nanoparticle-based topical formulation that cures psoriasis in a single dose, but leaves healthy skin intact. Specifically, we developed tris(hydroxymethyl)aminomethane-modified bioadhesive nanoparticles (Tris-BNPs) that exploit the high permeability characteristic of psoriasis to penetrate only psoriatic skin but not the healthy skin. Furthermore, as Tris-BNPs diffuse and penetrate into the epidermis, the Tris molecules slowly diffuse away, exposing the aldehyde groups of BNPs, which can bind to amine groups present within lesional skin, leading to long local retention of BNPs in lesions of psoriatic skin. The accumulated BNPs within lesions release corticosteroids over a ~ 3 day period to maintain local drug concentration above the therapeutic level. In addition to deeper penetration and longer retention compared with commercial psoriasis treatments, the topical applied Tris-BNPs were not affected by sweating, humidity, or active wiping due to their preferential accumulation between the stratum corneum and the basal cells of the epidermis. Overall, Tris-BNP as a topical formulation hold promise to overcome the limitations of current psoriasis treatment.

Identification and validation of HOXD3 and UNC5C as molecular signatures in keloid based on weighted gene co-expression network analysis.

BACKGROUND: Keloid is a benign proliferative disease characterized by excessive deposition of extracellular matrix collagen during skin wound healing. The mechanisms of keloid formation have not been fully elucidated, and the current treatment methods are not effective for all keloid patients. Therefore, there is an urgent need to find more effective therapies, and our research focused on identifying characteristic molecular signatures of keloid to explore potential therapeutic targets. METHODS: Gene expression profiles of keloid and control group samples were retrieved from the GEO database. Taking the GSE113619 dataset as the training set, the dataset collected skin tissues from non-lesion sites of healthy and keloid-prone individuals, denoted as Day0. The second sampling was performed 42 days later at the original sampling site of control and keloid groups, denoted as Day42.The 'limma' package and Venn diagram identified differentially expressed genes (DEGs) specific to keloid day42 versus day0 samples. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome pathway functional enrichment, and annotation of the characteristic genes were conducted on the Metascape website. Ingenuity canonical pathways, disease & function enrichment analysis and gene interaction network were performed and predicted in Ingenuity Pathway Analysis (IPA) software. Key module genes related to keloid were filtered out by Weighted Gene Co-expression Network Analysis (WGCNA). We utilized the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm to screen the characteristic genes in keloid by the 'glmnet' package. The area under the curve (AUC) of receiver operating characteristic (ROC) was utilized to determine the effectiveness of potential signatures in discriminating keloid samples from normal samples and performed by using the 'pROC' package. The enrich scores of 24 immune cells in each sample were calculated by the single-sample gene set enrichment analysis (ssGSEA) algorithm， and then the Gene Set Variation Analysis (GSVA) was performed. Finally, RNA from 4 normal and 6 keloid samples was extracted, and RT-qPCR and Western Blot validated the expression of characteristic genes. RESULTS: A total of 640 DEGs specific to keloid day42 versus day0 samples were detected. 69 key module genes were uncovered and implicated in 'NCAM signaling for neurite out-growth', 'oncogenic MAPK signaling', 'transmission across chemical synapses' pathways, and the mitotic cell cycle-related processes. Five characteristic genes (MTUS1, UNC5C, CEP57, NAA35, and HOXD3) of keloid were identified by LASSO, and among which UNC5C and HOXD3 were validated by ROC plot in external dataset, RT-qPCR and Western Blot in validation samples. The result of ssGSEA indicated that the infiltration of neutrophils showed a relatively higher abundance and natural killer cells with relatively low enrichment in the keloid group compared to the control group. UNC5C was correlated with more immune cells compared with other characteristic genes. CONCLUSION: In this study, characteristic genes associated with keloid were identified by bioinformatic approaches and verified in clinical validation samples, providing potential targets for the diagnosis and treatment of keloid.

Exosomes Derived from Epidermal Stem Cells Improve Diabetic Wound Healing.

Diabetic foot ulceration is a major diabetic complication with unmet needs. We investigated the efficacy of epidermal stem cells and epidermal stem cells-derived exosomes (ESCs-Exo) in improving impaired diabetic wound healing and their mechanisms of action. In vitro experiments showed that ESCs-Exo enhanced the proliferation and migration of diabetic fibroblasts and macrophages and promoted alternative or M2 macrophage polarization. In wounds of db/db mice, treatment with both epidermal stem cells and ESCs-Exo, when compared with fibroblast exosomes and PBS control, accelerated wound healing by decreasing inflammation, augmenting wound cell proliferation, stimulating angiogenesis, and inducing M2 macrophage polarization. Multiplex protein quantification of wound lysates revealed TGFß signaling influenced by ESCs-Exo. High-throughput sequencing of small RNAs contained in the ESCs-Exo showed higher proportions of microRNAs than those contained in fibroblast exosomes. In silico functional analysis showed that the ESCs-Exo microRNAs‒target genes were primarily involved in homeostatic processes and cell differentiation and highlighted regulatory control of phosphatidylinositol-3 kinase/protein kinase B and TGFß signaling pathways. This was also validated in vitro. Collectively, our results indicate that epidermal stem cells and ESCs-Exo are equally effective in promoting impaired diabetic wound healing and that ESCs-Exo treatment may be a promising and technically advantageous alternative to stem cell therapies.

CENPF as an independent prognostic and metastasis biomarker corresponding to CD4+ memory T cells in cutaneous melanoma.

Owing to recent advances in immunotherapies, the overall survival of patients with skin cutaneous melanoma (SKCM) has increased; however, the 5-year survival rate of metastatic patients remains poor. Skin cutaneous melanoma-upregulated genes were screened via analysis of differentially expressed genes (GSE3189 and GSE46517), and metastasis-related oncogenes were identified via weighted gene coexpression network analysis of the GSE46517 dataset. As confirmed by the Tumor Immune Estimation Resource, we found highly expressed centromere protein F (CENPF) in SKCM and its metastases. Immunostaining of human melanoma tissues demonstrated high CENPF expression. According to the Kaplan-Meier survival curve log-rank test, receiver-operating characteristic curve, and univariate and multivariate analyses, the Cancer Genome Atlas (TCGA) database suggested CENPF be a typical independent predictor of SKCM. The CIBERSORT algorithm classified the types of the immune cells from GSE46517 and showed higher proportion of CD4+ memory-activated T cells in metastatic melanoma. Single-sample gene set enrichment analysis of TCGA data confirmed the correlation between CENPF and activated CD4+ T cells. Centromere protein F was positively correlated with tumor mutational burden and CD4+ memory T cell markers (interleukin [IL]-23A, CD28, and CD62L), negatively associated with memory T cell maintenance factors (IL-7 and IL-15) by correlation analysis. Moreover, immunofluorescence showed high coexpression of CENPF and IL23A, CD4 in melanoma. Upregulated CENPF might lead to premature depletion of CD4+ memory T cells and immunosuppression. Nomogram indicated CENPF clinical predictive value for 1-, 3-, 5-, and 7-year melanoma overall survival. Therefore, CENPF plays a vital role in the progression and metastasis of melanoma and can be an effective therapeutic target.

Comprehensive analysis identifies IFI16 as a novel signature associated with overall survival and immune infiltration of skin cutaneous melanoma.

BACKGROUND: Skin cutaneous melanoma (SKCM) is the most common skin tumor with high mortality. The unfavorable outcome of SKCM urges the discovery of prognostic biomarkers for accurate therapy. The present study aimed to explore novel prognosis-related signatures of SKCM and determine the significance of immune cell infiltration in this pathology. METHODS: Four gene expression profiles (GSE130244, GSE3189, GSE7553 and GSE46517) of SKCM and normal skin samples were retrieved from the GEO database. Differentially expressed genes (DEGs) were then screened, and the feature genes were identified by the LASSO regression and Boruta algorithm. Survival analysis was performed to filter the potential prognostic signature, and GEPIA was used for preliminary validation. The area under the receiver operating characteristic curve (AUC) was obtained to evaluate discriminatory ability. The Gene Set Variation Analysis (GSVA) was performed, and the composition of the immune cell infiltration in SKCM was estimated using CIBERSORT. At last, paraffin-embedded specimens of primary SKCM and normal skin tissues were collected, and the signature was validated by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). RESULTS: Totally 823 DEGs and 16 feature genes were screened. IFI16 was identified as the signature associated with overall survival of SKCM with a great discriminatory ability (AUC > 0.9 for all datasets). GSVA noticed that IFI16 might be involved in apoptosis and ultraviolet response in SKCM, and immune cell infiltration of IFI16 was evaluated. At last, FISH and IHC both validated the differential expression of IFI16 in SKCM. CONCLUSIONS: In conclusion, our comprehensive analysis identified IFI16 as a signature associated with overall survival and immune infiltration of SKCM, which may play a critical role in the occurrence and development of SKCM.

Transient High Glucose Causes Persistent Vascular Dysfunction and Delayed Wound Healing by the DNMT1-Mediated Ang-1/NF-κB Pathway.

The progression of diabetic complications does not halt despite the termination of hyperglycemia, suggesting a metabolic memory phenomenon. However, whether metabolic memory exists in and affects the healing of diabetic wounds, as well as the underlying molecular mechanisms, remain unclear. In this study, we found that wound healing was delayed, and angiogenesis was decreased in mice with diabetes despite the normalization of glycemic control. Thus, we hypothesized that transient hyperglycemic spikes may be a risk factor for diabetic wound healing. We showed that transient hyperglycemia caused persistent damage to the vascular endothelium. Transient hyperglycemia directly upregulated DNMT1 expression, leading to the hypermethylation of Ang-1 and reduced Ang-1 expression, which in turn induced long-lasting activation of NF-κB and subsequent endothelial dysfunction. An in vivo study further showed that inhibition of DNMT1 promoted angiogenesis and accelerated diabetic wound healing by regulating the Ang-1/NF-κB signaling pathway. These results highlight the dramatic and long-lasting effects of transient hyperglycemic spikes on wound healing and suggest that DNMT1 is a target for diabetic vascular complications.

Correction to: Epidermal stem cells in wound healing and their clinical applications.

An amendment to this paper has been published and can be accessed via the original article.