Long non-coding RNA expression profiling in the lesional tissue and derived fibroblasts of keloid

Transcriptome-wide N6-methyladenosine (m6A) methylation profiling of long non-coding RNAs in ovarian endometriosis

N6-methyladenosine (m6A) methylation is the most prevalent internal epigenetic posttranscriptional mechanism for regulating mammalian RNA. Despite recent advances in determining the biological functions of m6A methylation, its association with the pathology of ovarian endometriosis remains uncertain. Herein, we performed m6A transcriptome-wide profiling to identify key lncRNAs with m6A modification involved in ovarian endometriosis development by bioinformatics analysis. We found the total m6A level was lower in ovarian endometriosis than in normal endometrium samples, with 9663 m6A peaks associated with 8989 lncRNAs detected in ovarian endometriosis and 9902 m6A peaks associated with 9210 lncRNAs detected in normal endometrium samples. These m6A peaks were primarily enriched within AAACU motifs. Functional enrichment analysis indicated that pathways involving the regulation of adhesion and development were significantly enriched in these differentially methylated lncRNAs. The regulatory relationships among lncRNAs, microRNAs (miRNAs), and mRNAs were identified by competing endogenous RNA (ceRNA) analysis and determination of the network regulating lncRNA-mRNA expression. Several specific lncRNA, including LINC00665, LINC00937, FZD10-AS1, DIO3OS and GATA2-AS1 which were differently expressed and modified by m6A, were validated using qRT-PCR and its interaction with infiltrating immune cells was explored. Furthermore, we found LncRNA DIO3OS promotes the invasion and migration of Human endometrial stromal cells (THESCs) and ALKBH5 regulates the expression of the lncRNA DIO3OS through m6A modification in vitro. Our study firstly revealed the transcriptome-wide map of m6A modification in lncRNAs of ovarian endometriosis. These findings may enable the determination of the underlying mechanism governing the pathogenesis of ovarian endometriosis and provide theoretical basis for further deeper research on the role of m6A in the development of ovarian endometriosis.

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.

Long Non-Coding RNA uc003jox.1 Promotes Keloid Fibroblast Proliferation and Invasion Through Activating the PI3K/AKT Signaling Pathway

The pathogenesis of keloids is complex and unclear, and the treatment of this condition remains challenging. The long non-coding RNA uc003jox.1 is highly expressed in keloid tissues compared with in normal skin tissues. We assessed the role of uc003jox.1 in keloid fibroblasts and its underlying mechanism, focusing on the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway. Keloid fibroblasts were transfected with a small interfering RNA targeting uc003jox.1. Colony formation, transwell, and flow cytometry assays were conducted to evaluate the proliferation, invasion, and apoptosis of keloid fibroblasts, respectively. The interaction between uc003jox.1 and the PI3K/AKT pathway was explored by using polymerase chain reaction and western blotting. Knockdown of uc003jox.1 markedly suppressed keloid fibroblast proliferation, clone-forming activity, and invasion, as well as promoted apoptosis. Silencing of uc003jox.1 decreased the phosphorylation levels of PI3K, AKT, and mammalian target of rapamycin and increased both the mRNA and protein expression levels of phosphatase and tensin homolog. Our in vitro results suggest that the long non-coding RNA uc003jox.1 can be used as a biomarker for keloid fibroblasts and that its expression is closely related to the proliferation and invasion of keloid fibroblasts through the PI3K/AKT/mammalian target of rapamycin pathway. Thus, uc003jox.1 shows potential as a treatment target for keloids.

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.

LncRNA H19 promotes keloid formation through targeting the miR-769-5p/EIF3A pathway

Keloid is a skin disease characterized by fibrous hyperplasia, which is often difficult to cure. Long non-coding RNAs (lncRNAs) have been shown to be associated with the development of many diseases. However, the role and mechanism of lncRNA H19 in keloid has been less studied. Our study found that lncRNA H19 expression was increased in keloid tissues and fibroblasts. Besides, H19 knockdown hindered the proliferation, migration, invasion, extracellular matrix (ECM) deposition, and enhanced the apoptosis of keloid fibroblasts. Further experiments showed that microRNA (miR)-769-5p could be sponged by H19, and its knockdown reversed the suppression effect of H19 knockdown on keloid formation. Eukaryotic initiation factor 3A (EIF3A) was found to be a target of miR-769-5p, and its overexpression inverted the inhibition effect of miR-769-5p overexpression on keloid formation. Moreover, the expression of EIF3A was regulated by H19 and miR-769-5p in keloid fibroblasts. Collectively, LncRNA H19 might play an active role in keloid formation, which might provide a new target for the treatment of keloid.

Epigenetic modification mechanisms involved in keloid: current status and prospect

Keloid, a common dermal fibroproliferative disorder, is benign skin tumors characterized by the aggressive fibroblasts proliferation and excessive accumulation of extracellular matrix. However, common therapeutic approaches of keloid have limited effectiveness, emphasizing the momentousness of developing innovative mechanisms and therapeutic strategies. Epigenetics, representing the potential link of complex interactions between genetics and external risk factors, is currently under intense scrutiny. Accumulating evidence has demonstrated that multiple diverse and reversible epigenetic modifications, represented by DNA methylation, histone modification, and non-coding RNAs (ncRNAs), play a critical role in gene regulation and downstream fibroblastic function in keloid. Importantly, abnormal epigenetic modification manipulates multiple behaviors of keloid-derived fibroblasts, which served as the main cellular components in keloid skin tissue, including proliferation, migration, apoptosis, and differentiation. Here, we have reviewed and summarized the present available clinical and experimental studies to deeply investigate the expression profiles and clarify the mechanisms of epigenetic modification in the progression of keloid, mainly including DNA methylation, histone modification, and ncRNAs (miRNA, lncRNA, and circRNA). Besides, we also provide the challenges and future perspectives associated with epigenetics modification in keloid. Deciphering the complicated epigenetic modification in keloid is hopeful to bring novel insights into the pathogenesis etiology and diagnostic/therapeutic targets in keloid, laying a foundation for optimal keloid ending.

Long non-coding RNA LINC01116 accelerates the progression of keloid formation by regulating miR-203/SMAD5 axis

BACKGROUND

Emerging evidence reveals the importance of long non-coding RNAs (lncRNAs) in the development and progression of keloid formation. However, the roles and molecular mechanism of lncRNA LINC01116 in the progression of keloid formation remain largely unknown.

METHODS

The expression levels of LINC01116, microRNA-203 (miR-203) and SMAD family member 5 (SMAD5) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell proliferation, migration and invasion were detected by Cell counting Kit-8 (CCK-8) assay and transwell assay. Flow cytometry and western blot assay were used to examine cell apoptosis and extracellular matrix (ECM) production. The interaction between miR-203 and LINC01116 or SMAD5 was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA Immunoprecipitation (RIP) and RNA pull-down assays.

RESULTS

LINC01116 and SMAD5 were upregulated while miR-203 was downregulated in keloid tissues and keloid fibroblasts. LINC01116 knockdown suppressed the proliferation, migration, invasion, and ECM production but induced apoptosis in keloid fibroblasts through enhancing miR-203 and inhibiting SMAD5. Moreover, SMAD5 was identified as a direct target of miR-203 and miR-203 could directly bind to LINC01116. Besides, LINC01116 regulated SMAD5 expression by targeting miR-203.

CONCLUSION

Downregulation of LINC01116 inhibited the progression of keloid formation by regulating miR-203/SMAD5 axis, which might provide a novel target for keloid therapy.

Long non coding RNA H19: An emerging therapeutic target in fibrosing diseases

Fibrosis is characterised by excessive deposition of the extracellular matrix (ECM) and develops because of fibroblast differentiation during the process of inflammation. There are few effective treatment options for this diseases due to the aetiology of fibrosis is not completely clarified. Long non-coding RNAs (lncRNAs), a type of ncRNA with a length of greater than 200 nucleotides without evident protein coding function, are important regulators of most biological and pathological processes, including participation, regulation or mediation of disease development. Among them, H19 is recently discovered as a class of lncRNAs which is related to fibrotic disease and inflammation. These observations implied a potential role for H19 as a promising therapeutic targets for treatment of fibrotic diseases. In this review, we will describe the characteristics of H19 and summarise recent advances in the mechanisms of H19 in the process of fibrosis. Finally, we will succinctly discuss the recent progress of the involvement of H19 in the development and pathogenesis of fibrosis diseases.