NEAT1 Knockdown Inhibits Keloid Fibroblast Progression by miR-196b-5p/FGF2 Axis

Identification of potential therapeutic target SPP1 and related RNA regulatory pathway in keloid based on bioinformatics analysis

OBJECTIVE

To explore the complex mechanisms of keloid, new approaches have been developed by different strategies. However, conventional treatment did not significantly reduce the recurrence rate. This study aimed to identify new biomarkers and mechanisms for keloid progression through bioinformatics analyses.

METHODS

In our study, microarray datasets for keloid were downloaded from the GEO database. Differentially expressed genes (DEGs) were identified by R software. Multiple bioinformatics tools were used to identify hub genes, and reverse predict upstream miRNAs and lncRNA molecules of target hub genes. Finally, the total RNA-sequencing technique and miRNA microarray were combined to validate the identified genes.

RESULTS

Thirty-one DEGs were screened out and the upregulated hub gene SPP1 was finally identified, which was consistent with our RNA-sequencing analysis results and validation dataset. In addition, a ceRNA network of mRNA (SPP1)-miRNA (miR-181a-5p)-lncRNA (NEAT1, MALAT1, LINC00667, NORAD, XIST and MIR4458HG) was identified by the bioinformatics databases. The results of our miRNA microarray showed that miR-181a-5p was upregulated in keloid, also we found that the lncRNA NEAT1 could affect keloid progression by retrieving the relevant literature.

CONCLUSIONS

We speculate that SPP1 is a potential candidate biomarker and therapeutic target for patients with keloid, and NEAT1/miR-181a-5p/SPP1 might be the RNA regulatory pathway that regulates keloid formation.

Expression of lncRNA LINC00943 in lung squamous cell carcinoma and its relationship with tumor progression

BACKGROUND

Molecular biology has been applied to the diagnosis, prognosis and treatment of various diseases, and long noncoding RNA LINC00943 (lncRNA LINC00943; LINC00943) plays an important role in a variety of cancers. Therefore, this study explored the prognostic role of LINC00943 in lung squamous cell carcinoma (LUSC) and understood its impact on the development of LUSC.

METHODS

There are 89 LUSC patients were involved in current assay. By detecting the expression of LINC00943 and miR-196b-5p in tissues and cells, LINC00943 and its correlation with the characteristics of clinical data were analyzed. The biological function of LINC00943 was studied by Transwell migration and invasion assays. In addition, Pearson correlation coefficient and luciferase activity experiments were chosen to characterize the relationship between LINC00943 and miR-196b-5p and explore the mechanism of LINC00943.

RESULTS

Compared with normal controls, LINC00943 expression in LUSC tissues and cells was significantly reduced, miR-196b-5p was markedly increased, there was a negative correlation between LINC00943 and miR-196b-5p. According to the in vitro cell experiments, migration and invasion of LUSC cells were suppressed by overexpression of LINC00943. Besides, LINC00943 was demonstrated to have prognostic power and targeting miR-196b-5p was involved in the progression of LUSC.

CONCLUSIONS

Overexpression of LINC00943 was molecular sponge for miR-196b-5p that controlled the deterioration of LUSC, which had great potential as a prognostic biomarker for LUSC.

Epigenetic modification: A novel insight into diabetic wound healing

Wound healing is an intricate and fine regulatory process. In diabetic patients, advanced glycation end products (AGEs), excessive reactive oxygen species (ROS), biofilm formation, persistent inflammation, and angiogenesis regression contribute to delayed wound healing. Epigenetics, the fast-moving science in the 21st century, has been up to date and associated with diabetic wound repair. In this review, we go over the functions of epigenetics in diabetic wound repair in retrospect, covering transcriptional and posttranscriptional regulation. Among these, we found that histone modification is widely involved in inflammation and angiogenesis by affecting macrophages and endothelial cells. DNA methylation is involved in factors regulation in wound repair but also affects the differentiation phenotype of cells in hyperglycemia. In addition, noncodingRNA regulation and RNA modification in diabetic wound repair were also generalized. The future prospects for epigenetic applications are discussed in the end. In conclusion, the study suggests that epigenetics is an integral regulatory mechanism in diabetic wound healing.

Aligned electrospun fibers of different diameters for improving cell migration capacity

Electrospun fibers have gained significant attention as scaffolds in skin tissue engineering due to their biomimetic properties, which resemble the fibrous extracellular matrix. The morphological characteristics of electrospun fibers play a crucial role in determining cell behavior. However, the effects of electrospun fibers' arrangement and diameters on human skin fibroblasts (HSFs) remain elusive. Here, we revealed the impact of electrospun fiber diameters (700 nm, 2000 nm, and 3000 nm) on HSFs' proliferation, migration, and functional expression. The results demonstrated that all fibers exhibited good cytocompatibility. HSFs cultured on nanofibers (700 nm diameter) displayed a more dispersed and elongated morphology. Conversely, fibers with a diameter of 3000 nm exhibited a reduced specific surface area and lower adsorption of adhesion proteins, resulting in enhanced cell migration speed and effective migration rate. Meanwhile, the expression levels of migration-related genes and proteins were upregulated at 48 h for the 3000 nm fibers. This study demonstrated the unique role of fiber diameters in controlling the physiological functions of cells, especially decision-making and navigating migration in complex microenvironments of aligned electrospun fibers, and highlights the utility of these bioactive substitutes in skin tissue engineering applications.

Non-coding RNAs in hypertrophic scars and keloids: Current research and clinical relevance: A review

Hypertrophic scars (HS) and keloids (KD) are lesions that develop as a result of excessive fibroblast proliferation and collagen deposition in response to dermal injury, leading to dysregulation of the inflammatory, proliferative, and remodeling phases during wound healing. HS and KD affect up to 90 % of the population and are associated with lower quality of life, physical health, and mental status in patients. Efficient targeted treatment represents a significant challenge, primarily due to our limited understanding of their underlying pathogenesis. Non-coding RNAs (ncRNAs), which constitute a significant portion of the human transcriptome with minimal or no protein-coding capacity, have been implicated in various cellular physiologies and pathologies and may serve as diagnostic indicators or therapeutic targets. NcRNAs have been found to be aberrantly expressed and regulated in HS and KD. This review provides a summary of the expression profiles and molecular mechanisms of three common ncRNAs, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in HS and KD. It also discusses their potential as biomarkers for the diagnosis and treatment of these diseases and provides novel insights into epigenetic-based diagnosis and treatment strategies for HS and KD.

IncRNA MIAT Accelerates Keloid Formation by miR-411-5p/JAG1 Axis

The long non-coding RNA (lncRNA) myocardial infarction-associated transcript (MIAT) regulates the biological functions of many kinds of cells. The aim of this study is to explore the mechanism of MIAT and how it affects keloid progression. The expressions of MIAT, JAG1, and miR-411-5p in keloid tissues and keloid fibroblasts (KEL FIBs) were quantified by conducting Western blot and quantitative reverse transcription polymerase chain reaction analyses. The influences of MIAT, JAG1, and miR-411-5p on the abilities of KEL FIBs to proliferate, migrate, and invade were assessed by means of the CCK-8, wound healing, and Transwell experiments. To determine the binding relationship among MIAT, JAG1, and miR-411-5p, we performed luciferase reporter and RIP experiments. In keloid tissues and KEL FIBs, MIAT and JAG1 were upregulated while miR-411-5p was downregulated. Knocking-down MIAT or JAG1 significantly inhibited proliferation, migration and invasion. On the contrary, suppressing miR-411-5p expression produced an opposite effect. With regard to mechanisms, MIAT sponged miR-411-5p, which targeted JAG1. MIAT accelerates keloid formation by modulating the miR-411-5p/JAG1 axis.

Mechanisms underlying pathological scarring by fibroblasts during wound healing

Pathological scarring is an abnormal outcome of wound healing, which often manifests as excessive proliferation and transdifferentiation of fibroblasts (FBs), and excessive deposition of the extracellular matrix. FBs are the most important effector cells involved in wound healing and scar formation. The factors that promote pathological scar formation often act on the proliferation and function of FB. In this study, we describe the factors that lead to abnormal FB formation in pathological scarring in terms of the microenvironment, signalling pathways, epigenetics, and autophagy. These findings suggest that understanding the causes of abnormal FB formation may aid in the development of precise and effective preventive and treatment strategies for pathological scarring that are associated with improved quality of life of patients.

Advances in the pathogenesis and clinical application prospects of tumor biomolecules in keloid

Keloid scarring is a kind of pathological healing manifestation after skin injury and possesses various tumor properties, such as the Warburg effect, epithelial-mesenchymal transition (EMT), expression imbalances of apoptosis-related genes and the presence of stem cells. Abnormal expression of tumor signatures is critical to the initiation and operation of these effects. Although previous experimental studies have recognized the potential value of a single or several tumor biomolecules in keloids, a comprehensive evaluation system for multiple tumor signatures in keloid scarring is still lacking. This paper aims to summarize tumor biomolecules in keloids from the perspectives of liquid biopsy, genetics, proteomics and epigenetics and to investigate their mechanisms of action and feasibility from bench to bedside. Liquid biopsy is suitable for the early screening of people with keloids due to its noninvasive and accurate performance. Epigenetic biomarkers do not require changes in the gene sequence and their reversibility and tissue specificity make them ideal therapeutic targets. Nonetheless, given the ethnic specificity and genetic predisposition of keloids, more large-sample multicenter studies are indispensable for determining the prevalence of these signatures and for establishing diagnostic criteria and therapeutic efficacy estimations based on these molecules.

Circular RNA hsa_circ_0043688 serves as a competing endogenous RNA for microRNA-145-5p to promote the progression of Keloids via Fibroblast growth factor-2

Background

Keloids are benign fibroproliferative skin tumors. Circular RNA (circRNA) hsa_circ_0043688 has been exhibited to the freakishly expressed in keloid tissues. Here, we aimed to investigate the regulatory network of hsa_circ_0043688 in the pathological process of keloid.

Methods

Hsa_circ_0043688, microRNA‐145‐5p (miR‐145‐5p), and Fibroblast growth factor‐2 (FGF2) level were detected using RT‐qPCR. Cell viability, proliferation, apoptosis, invasion, and migration were investigated using Cell Counting Kit‐8 (CCK‐8), 5‐ethynyl‐2′‐deoxyuridine (EdU), flow cytometry, transwell, and wound healing assays, respectively. Western blot analysis of protein levels of FGF2, CyclinD1, Collagen I, and Collagen III. After the prediction of Circinteractome and Starbase, their interaction was verified based on a dual‐luciferase reporter and RIP assays.

Results

Increased hsa_circ_0043688 and FGF2, and decreased miR‐145‐5p in keloids samples and fibroblasts were found. Also, hsa_circ_0043688 absence hindered proliferation, invasion, migration, and boost apoptosis of keloid fibroblasts. In mechanism, hsa_circ_0043688 modulated FGF2 content via sponging miR‐145‐5p.

Conclusion

Hsa_circ_0043688 knockdown inhibited cell growth and metastasis of keloid fibroblasts via miR‐145‐5p/FGF2, providing a new mechanism to understand the keloid progression.

Silencing circular RNAPTPN12 promoted the growth of keloid fibroblasts by activating Wnt signaling pathway via targeting microRNA-21-5p

Keloid is a skin disease marked by fibroplasia, and fibroblasts viability plays a considerable part in keloid. Our research was devoted to assessing the involvement and mechanism of circPTPN12 in keloid. The level of circPTPN12 and miR-21-5p was estimated by qRT-PCR in keloid tissues and cells. MTT analysis was devoted to evaluating the multiplication of keloid fibroblasts. Additionally, transwell assay was dedicated to verifying cell migration and invasion. Furthermore, keloid fibroblasts apoptosis level was assessed adopting flow cytometry, and the relevancy between miR-21-5p and circPTPN12, miR-21-5p, and SMAD7 was assessed by dual luciferase assay. Similarly, RIP and RNA pull-down assay verified the relevance between genes. Moreover, levels of SMAD7 and proteins concerned in Wnt signaling pathway were appraised by Western blot. The level of circPTPN12 declined in keloid. circPTPN12 knockout could enhance the multiplication, migration, invasion, and decline apoptosis of keloid fibroblasts. Indeed, miR-21-5p could be packed with circPTPN12 sponge, SMAD7 was downstream effect factor of miR-21-5p, and miR-21-5p inhibitors partially reversed the promoting effect of silencing circPTPN12 on keloid formation. Otherwise, the level of SMAD7 was adjusted by circPTPN12 and miR-21-5p. Silencing circPTPN12 targeted miR-21-5p and activated Wnt pathway to accelerate keloid fibroblasts growth. Taken together, silencing circPTPN12 promotes the growth of keloid fibroblasts by activating Wnt pathway targeting miR-21-5p. CircPTPN12 may play a considerable part in keloid formation, which supplies a reference for molecularly targeted therapy keloid.

Long non-coding RNA H19 aggravates keloid progression by upregulating SMAD family member 5 expression via miR-196b-5p

Accumulating evidence suggests that long non-coding RNAs (lncRNAs) participate in the formation and development of keloids, a benign tumor. In addition, lncRNA H19 has been shown to act on the biological processes of keloids. This study aimed to identify other important mechanisms of the effect of lncRNA H19 on keloid formation. The H19, miR-196b-5p, and SMAD family member 5 (SMAD5) expression levels were detected using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blotting. Subcellular localization of lncRNA H19 was detected using a nuclear-cytoplasmic separation assay. Cell viability and proliferation were measured using counting kit-8 and colony formation assays. Bax and Bcl-2 levels were examined using Western blot analysis. The interaction between H19 and miR-196b-5p or SMAD5 was verified using a dual-luciferase reporter assay. H19 and SMAD5 expression was upregulated in keloid tissue and fibroblasts, whereas miR-196b-5p expression was downregulated. Knockdown of H19, overexpression of miR-196b-5p, or knockdown of SMAD5 inhibited the viability and proliferation of keloid fibroblasts and promoted apoptosis. Overexpression of H19 or SMAD5 and knockdown of miR-196b-5p promoted viability and proliferation and inhibited apoptosis. miR-196b-5p was identified as a H19 sponge, and SMAD5 was identified as a miR-196b-5p target. The combination of lncRNA H19 and miR-196b-5p regulates SMAD5 expression and promotes keloid formation, thus providing a new direction for keloid treatment.

LncRNA HOXA11-AS aggravates the keloid formation by targeting miR-148b-3p/IGFBP5 axis

Long non-coding RNA (lncRNA) homeobox (HOX) A11 antisense (HOXA11-AS) mediates cell-biological phenotypes of keloid fibroblasts and influence the keloid progression, yet the underlying mechanism need to be further understood. HOXA11-AS, microRNA miR-148b-3p and Insulin like growth factor binding protein 5 (IGFBP5) expression were detected by RT-qPCR or western blot. CCK-8 and colony formation assays were applied to examine the cell proliferation. The cell migration was determined via Transwell migration assays. The cell apoptosis was determined by western blots with anti-Bax antibodies and anti-Cleaved Caspase-3 antibodies. The interplay between miR-148b-3p, HOXA11-AS and IGFBP5 was confirmed by luciferase reporter or RNA immunoprecipitation assay. The amplification of HOXA11-AS and IGFBP5 was detected in keloid and keloid fibroblasts, while miR-148b-3p expression was reduced. Moreover, downregulation of HOXA11-AS in keloid fibroblasts inhibited cell proliferation, migration and triggered apoptosis. Mechanically, HOXA11-AS was proved to sponge miR-148b-3p and abrogate the inhibition on miR-148b-3p target, IGFBP5 mRNA, thus promoting keloid fibroblasts proliferation, migration and inhibiting apoptosis. These results find that HOXA11-AS promotes keloid progression by miR-148b-3p/IGFBP5 axis, suggesting the potential of targeting HOXA11-AS/miR-148b-3p/IGFBP5 axis to combat keloid.

Long non-coding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) regulates fibroblast growth factor receptor substrate 2 (FRS2) by targeting microRNA (miR)-29-3p in hypertrophic scar fibroblasts

Long non-coding RNAs (lncRNAs) play crucial roles in human diseases. However, the detailed role of lncRNAs in hypertrophic scar fibroblasts (HSFs) is inadequately understood. This study aimed to investigate the potential role of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in hypertrophic scarring. Expression of lncRNAs, miRNAs, and genes were detected by polymerase chain reaction; protein expression was evaluated using western blotting. Cellular function was determined using the CCK-8 assay. The interaction between microRNA (miR)-29-3p and NEAT1 or fibroblast growth factor receptor substrate 2 (FRS2) was verified by luciferase and RNA pull-down assays. The results showed that NEAT1 was overexpressed in the hypertrophic dermis and in HSFs. However, knockdown of NEAT1 suppressed the proliferation and extracellular matrix (ECM) production of HSFs. Moreover, NEAT1 functioned as a competing endogenous RNA to upregulate FRS2 by sponging miR-29-3p. Downregulation of miR-29-3p or overexpression of FRS2 antagonized the effects of NEAT1 knockdown and promoted HSF proliferation and ECM release. In conclusion, NEAT1 knockdown protected against hypertrophic scarring by modulating the miR-29-3p/FRS2 axis, which is a viable target in scar treatment.

The epigenetics of keloids

Keloid scarring is a fibroproliferative disorder of the skin with unknown pathophysiology, characterised by fibrotic tissue that extends beyond the boundaries of the original wound. Therapeutic options are few and commonly ineffective, with keloids very commonly recurring even after surgery and adjunct treatments. Epigenetics, defined as alterations to the DNA not involving the base-pair sequence, is a key regulator of cell functions, and aberrant epigenetic modifications have been found to contribute to many pathologies. Multiple studies have examined many different epigenetic modifications in keloids, including DNA methylation, histone modification, microRNAs and long non-coding RNAs. These studies have established that epigenetic dysregulation exists in keloid scars, and successful future treatment of keloids may involve reverting these aberrant modifications back to those found in normal skin. Here we summarise the clinical and experimental studies available on the epigenetics of keloids, discuss the major open questions and future perspectives on the treatment of this disease.