Phosphodiesterase 4 is overexpressed in keloid epidermal scars and its inhibition reduces keratinocyte fibrotic alterations.

BACKGROUND: Epidermal remodeling and hypertrophy are hallmarks of skin fibrotic disorders, and keratinocyte to mesenchymal (EMT)-like transformations drive epidermis alteration in skin fibrosis such as keloids and hypertrophic scars (HTS). While phosphodiesterase 4 (PDE4) inhibitors have shown effectiveness in various fibrotic disorders, their role in skin fibrosis is not fully understood. This study aimed to explore the specific role of PDE4B in epidermal remodeling and hypertrophy seen in skin fibrosis. METHODS: In vitro experiments examined the effects of inhibiting PDE4A-D (with Roflumilast) or PDE4B (with siRNA) on TGFß1-induced EMT differentiation and dedifferentiation in human 3D epidermis. In vivo studies investigated the impact of PDE4 inhibition on HOCl-induced skin fibrosis and epidermal hypertrophy in mice, employing both preventive and therapeutic approaches. RESULTS: The study found increased levels of PDE4B (mRNA, protein) in keloids > HTS compared to healthy epidermis, as well as in TGFß-stimulated 3D epidermis. Keloids and HTS epidermis exhibited elevated levels of collagen Iα1, fibronectin, αSMA, N-cadherin, and NOX4 mRNA, along with decreased levels of E-cadherin and ZO-1, confirming an EMT process. Inhibition of both PDE4A-D and PDE4B prevented TGFß1-induced Smad3 and ERK1/2 phosphorylation and mesenchymal differentiation in vitro. PDE4A-D inhibition also promoted mesenchymal dedifferentiation and reduced TGFß1-induced ROS and keratinocyte senescence by rescuing PPM1A, a Smad3 phosphatase. In vivo, PDE4 inhibition mitigated HOCl-induced epidermal hypertrophy in mice in both preventive and therapeutic settings. CONCLUSIONS: Overall, the study supports the potential of PDE4 inhibitors, particularly PDE4B, in treating skin fibrosis, including keloids and HTS, shedding light on their functional role in this condition.

Giant corneal keloid following Descemet stripping automated endothelial keratoplasty for the treatment of corneal decompensation secondary to trauma.

PURPOSE: This report aims to present a case of corneal keloid caused by chronic corneal insult after trauma and Descemet stripping automated endothelial keratoplasty (DSAEK). CASE PRESENTATION: A 35-year-old male with a history of vision loss in the right eye was referred to our hospital. The patient underwent Ahmed Glaucoma Valve Implantation to alleviate elevated intraocular pressure after ocular trauma to the same eye. One year following the procedure, the eye developed endothelial failure, leading to the performance of Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK) with repositioning of the shunt tube. Upon initial examination, a well-circumscribed elevated white opaque lesion involving the central corneal surface of the RE was observed. Based on the patient's clinical history, slit lamp examination, and UBM findings, the diagnosis of corneal keloid was established. Superficial keratectomy was performed. Histopathological analysis confirmed the diagnosis of corneal keloid. Following the procedure, BCVA improved slightly. However, 3 months later, the patient underwent a penetrating keratoplasty for visual rehabilitation. CONCLUSION: Corneal keloids should be considered following any form of ocular trauma, particularly in cases involving ocular surgery. Diagnosing corneal keloids can sometimes be challenging due to the variety of potential differentials; however, by carefully evaluating the patient's medical history and clinical presentation, we can effectively narrow down the differential diagnosis of corneal conditions.

[Effects of low dose skin tissue derived peptides on the function and collagen expression of keloid fibroblasts].

This study aims to investigate the effects of the skin tissue derived peptides on proliferation, apoptosis, migration and collagen expressions in keloid fibroblasts. From January 2015 to January 2017, patients with hypertrophic scar who underwent surgical excision in department of plastic surgery of Nanjing maternal and child health hospital were included in this retrospective study. Four peptides were selected from the differential peptides between human hypertrophic scar and normal skin tissue. They were named as peptide deregulated in hypertrophic scar 2-5 (PDHPS2-5). Bioinformatics and functional analysis were performed. A low dose of 10 µmol/L of four peptides were respectively added to the culture medium of human primary keloid fibroblasts for 24 h. Cell counting kit-8 (CCK-8) were used to detect the changes in cell viability. Cell apoptosis was detected by flow cytometry. Cell migration ability was checked by Transwell chamber. The protein expressions of collagen COL1A2 (Collagen type I alpha 2) and the myofibroblast marker gene ACTA2 (Actin alpha 2) were analyzed by Western blot. The results showed that bioinformatics prediction analysis revealed that peptide PDHPS4 has the longest half-life and the highest thermal stability. Compared with the control group, low dose of four peptides had no significant effect on the survival rate and apoptosis of keloid fibroblasts tested by CCK-8 assay and flowcytometry. Transwell analysis showed that one peptides (PDHPS5) can significantly inhibit the cell migration ability (The optical density value in Control is 0.81±0.11, in PDHPS5 is 0.27±0.03, t=8.61, P=0.001). Western blot analysis showed that four peptides (PDHPS2, PDHPS3, PDHPS4, PDHPS5) can significantly inhibit the protein expressions of COL1A2 (The relative protein band intensity in Control is 1.02±0.02, in PDHPS2 is 0.21±0.04, in PDHPS3 is 0.26±0.03, in PDHPS4 is 0.53±0.04, in PDHPS5 is 0.73±0.04, t=31.38, 38.54, 18.88, 11.07 respectively, all P value are less than 0.01). Three peptides (PDHPS2, PDHPS3, PDHPS5) can significantly inhibit the protein expressions of ACTA2 (The relative protein band intensity in Control is 1.02±0.02, in PDHPS2 is 0.64±0.05, in PDHPS3 is 0.77±0.06, in PDHPS5 is 0.47±0.07, t=12.08, 6.38, 14.06 respectively, all P value are less than 0.01). In conclusion, the differentially expressed peptides in human hypertrophic scar tissue can affect the function of keloid fibroblasts and collagen expressions to varying degrees. Among them, two peptides (PDHPS2,PDHPS3) significantly inhibit the protein expressions of COL1A2 and ACTA2. The peptide PDHPS5 has high stability, significantly suppresses cell migration, and reduces the protein expressions of COL1A2 and ACTA2, which may provide a new strategy for scar prevention and treatment.

The role of IL-17 and Th17 cells in keloid pathogenesis.

Keloids are characterized histologically by excessive fibroblast proliferation and connective tissue deposition, and clinically by scar tissue extending beyond the original site of skin injury. These scars can cause pruritus, pain, physical disfigurement, anxiety, and depression. As a result, keloid patients often have a diminished quality of life with a disproportionate burden on ethnic minorities. Despite advances in understanding keloid pathology, there is no effective Food and Drug Administration (FDA)-approved pharmacotherapy. Recent studies have highlighted the possible pathologic role of T helper (Th)17 cells and interleukin (IL)-17 in keloid formation, as well as their implication in other inflammatory disorders. This systematic review characterizes the role of Th17 cells and IL-17 in keloid pathogenesis, highlighting this pathway as a potential therapeutic target. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive search on PubMed, Embase, MEDLINE, and Web of Science databases on June 5, 2024. The search included terms related to Th17 cells, IL-17, and keloids. Thirteen studies met the inclusion criteria, comprising basic science and bioinformatic studies focusing on Th17 cells and IL-17. Key findings include increased Th17 cell infiltration and IL-17 expression in keloids, IL-17's role in amplifying the inflammatory and fibrotic response via the promotion of IL-6 expression, and IL-17's involvement in upregulating fibrotic markers via SDF-1 and HIF-1α pathways. IL-17 also activates the transforming growth factor beta (TGF-ß)/Smad pathway in keloid fibroblasts. Th17 cells and IL-17 significantly contribute to the inflammatory and fibrotic processes in keloid pathogenesis. Therefore, targeting the IL-17 pathway offers a potential new therapeutic target to improve keloid patients' outcomes. Future research could further elucidate the role of Th17 cells and IL-17 in keloid pathogenesis and assess the safety and efficacy of targeting this pathway in human studies.

Adipose stem cell exosomes promote mitochondrial autophagy through the PI3K/AKT/mTOR pathway to alleviate keloids.

BACKGROUND: Fibrosis with unrelieved chronic inflammation is an important pathological change in keloids. Mitochondrial autophagy plays a crucial role in reducing inflammation and inhibiting fibrosis. Adipose stem cell-derived exosomes, a product of adipose stem cell paracrine secretion, have pharmacological effects, such as anti-inflammatory and antiapoptotic effects, and mediate autophagy. Therefore, this study aims to investigate the function and mechanism of adipose stem cell exosomes in the treatment of keloids. METHOD: We isolated adipose stem cell exosomes under normoxic and hypoxic condition to detect their effects on keloid fibroblast proliferation, migration, and collagen synthesis. Meanwhile, 740YPDGFR (PI3K/AKT activator) was applied to detect the changes in autophagic flow levels and mitochondrial morphology and function in keloid fibroblasts. We constructed a human keloid mouse model by transplanting human keloid tissues into six-week-old (20-22 g; female) BALB/c nude mice, meanwhile, we applied adipose stem cell exosomes to treat the mouse model and observed the retention and effect of ADSC exosomes in vivo. RESULTS: ADSC exosomes can inhibit the PI3K/AKT/mTOR signaling pathway. The exosomes of ADSCs decreased the inflammatory level of KFs, enhanced the interaction between P62 and LC3, and restored the mitochondrial membrane potential. In the human keloid mouse model, ADSC exosomes can exist stably, promote mitochondrial autophagy in keloid tissue, improve mitochondrial morphology, reduce inflammatory reaction and fibrosis. Meanwhile, At the same time, the exosomes derived from hypoxic adipose stem cells have played a more effective role in both in vitro and in vivo experiments. CONCLUSIONS: Adipose stem cell exosomes inhibited the PI3K/AKT/mTOR pathway, activated mitochondrial autophagy, and alleviated keloid scars.

The diagnostic value and associated molecular mechanism study for fibroblast-related mitochondrial genes on keloid.

PURPOSE: This study aims to reveal the mechanism of fibroblast-related mitochondrial genes on keloid formation and explore promising signature genes for keloid diagnosis. METHOD: The distribution of fibroblasts between the keloid sample and control sample based on three keloid datasets, followed by the differentially expressed genes (DEGs) investigation and associated enrichment analysis. Then, hub genes were explored based on DEGs, mitochondrial genes from an online database, as well as fibroblast-related genes that were revealed by WCGNA. Subsequently, signature genes were screened through machine learning, and their diagnostic value was validated by nomogram. Moreover, the targeted drugs and related transcriptional regulation of these genes were analyzed. Finally, the verification analysis was performed on signature genes using qPCR analysis. RESULT: A total of totally 329 DEGs were revealed based on three datasets, followed by enrichment analysis. WGCNA revealed a total of 258 fibroblast-related genes, which were primarily assembled in functions like muscle tissue development. By using machine learning, we screened four signature genes (ACSF2, ALDH1B1, OCIAD2, and SIRT4) based on eight hub genes (fibroblast-related mitochondrial genes). Nomogram and validation analyses confirmed the well-diagnostic performance of these four genes in keloid. Immune infiltration and drug correlation analyses showed that SIRT4 was significantly associated with immune cell type 2 T helper cells and molecular drug cyclosporin. All these findings provided new perspectives for the clinical diagnosis and therapy of keloid. CONCLUSION: The fibroblast-related mitochondrial genes including SIRT4, OCIAD2, ALDH1B1, and ACSF2 were novel signature genes for keloid diagnosis, offering novel targets and strategies for diagnosis and therapy of keloid.

Phosphodiesterase 4 is overexpressed in human keloids and its inhibition reduces fibroblast activation and skin fibrosis.

There is a pressing medical need for improved treatments in skin fibrosis including keloids and hypertrophic scars (HTS). This study aimed to characterize the role of phosphodiesterase 4 (PDE4), specifically PDE4B in fibrotic skin remodeling in vitro and in vivo. In vitro, effects of PDE4A-D (Roflumilast) or PDE4B (siRNA) inhibition on TGFß1-induced myofibroblast differentiation and dedifferentiation were studied in normal (NHDF) and keloid (KF) human dermal fibroblasts. In vivo, the role of PDE4 on HOCl-induced skin fibrosis in mice was addressed in preventive and therapeutic protocols. PDE4B (mRNA, protein) was increased in Keloid > HTS compared to healthy skin and in TGFß-stimulated NHDF and KF. In Keloid > HTS, collagen Iα1, αSMA, TGFß1 and NOX4 mRNA were all elevated compared to healthy skin confirming skin fibrosis. In vitro, inhibition of PDE4A-D and PDE4B similarly prevented TGFß1-induced Smad3 and ERK1/2 phosphorylation and myofibroblast differentiation, elevated NOX4 protein and proliferation in NHDF. PDE4A-D inhibition enabled myofibroblast dedifferentiation and curbed TGFß1-induced reactive oxygen species and fibroblast senescence. In KF PDE4A-D inhibition restrained TGFß1-induced Smad3 and ERK1/2 phosphorylation, myofibroblast differentiation and senescence. Mechanistically, PDE4A-D inhibition rescued from TGFß1-induced loss in PPM1A, a Smad3 phosphatase. In vivo, PDE4 inhibition mitigated HOCl-induced skin fibrosis in mice in preventive and therapeutic protocols. The current study provides novel evidence evolving rationale for PDE4 inhibitors in skin fibrosis (including keloids and HTS) and delivered evidence for a functional role of PDE4B in this fibrotic condition.

Comprehensive Insights into Keloid Pathogenesis and Advanced Therapeutic Strategies.

Keloid scars, characterized by abnormal fibroproliferation and excessive extracellular matrix (ECM) production that extends beyond the original wound, often cause pruritus, pain, and hyperpigmentation, significantly impacting the quality of life. Keloid pathogenesis is multifactorial, involving genetic predisposition, immune response dysregulation, and aberrant wound-healing processes. Central molecular pathways such as TGF-ß/Smad and JAK/STAT are important in keloid formation by sustaining fibroblast activation and ECM deposition. Conventional treatments, including surgical excision, radiation, laser therapies, and intralesional injections, yield variable success but are limited by high recurrence rates and potential adverse effects. Emerging therapies targeting specific immune pathways, small molecule inhibitors, RNA interference, and mesenchymal stem cells show promise in disrupting the underlying mechanisms of keloid pathogenesis, potentially offering more effective and lasting treatment outcomes. Despite advancements, further research is essential to fully elucidate the precise mechanisms of keloid formation and to develop targeted therapies. Ongoing clinical trials and research efforts are vital for translating these scientific insights into practical treatments that can markedly enhance the quality of life for individuals affected by keloid scars.

Systematic review of dupilumab safety and efficacy for treatment of keloid scars.

Keloids, characterized by excessive scar formation following dermal inflammation, pose a therapeutic challenge due to high recurrence rates. Radiation therapy, contraindicated in children, can minimize recurrence post-surgical removal. Dupilumab, which inhibits the pro-fibrotic interleukin-4/interleukin-13 axis, may effectively manage keloids when intralesional corticosteroid injections are unsuccessful. It may also prevent recurrence post-surgery in pediatric patients. This systematic review assesses the efficacy and safety of dupilumab for the treatment of keloids. Through a systematic search adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we identified and analyzed outcomes from three case reports and three case series studies, totaling 15 patients. Results indicate variable responses to treatment, including significant improvements, no clinical change, and worsening of keloid symptoms. Additional research is needed to recommend using dupilumab to treat keloids (Grade D). Treatment response variability may be linked to differences in interleukin-4/interleukin-13 activity between active and inactive keloids. Additionally, the unintended promotion of T helper 17 cell differentiation by dupilumab may worsen keloids.

Using Neuromodulators to Improve Scar Formation, Keloids, Rosacea, and Antiaging.

BACKGROUND: Botulinum toxin A (BoNT-A) treatment has many uses in dermatology. Its mechanism of action and long-term effects for scar formation, rosacea, and antiaging are still being investigated. OBJECTIVE: To conduct a literature review on BoNT-A to further investigate its use in scar formation, rosacea, and antiaging. METHODS: A literature review was conducted using PubMed on botulinum toxin treatment for scar formation, rosacea, and antiaging. Studies discussing the toxin mechanism of action and treatment algorithm were included. The authors also provided their personal experience in BoNT-A use for these 3 conditions. RESULTS: The mechanism of action of Botulinum toxin A in improving scar formation, rosacea, and antiaging is now better understood. While it is effective in the short term, little is still known about how frequently treatment needs to be repeated and if there are any long-term effects. CONCLUSION: While in vitro studies have supporting evidence on the mechanism of action of BoNT-A on scar formation, rosacea, and antiaging, further studies are needed to identify long-term treatment effects.

Zinc-Alpha-2-Glycoprotein Peptide Downregulates Type I and III Collagen Expression via Suppression of TGF-ß and p-Smad 2/3 Pathway in Keloid Fibroblasts and Rat Incisional Model.

BACKGROUND: Keloids and hypertrophic scars result from abnormal collagen accumulation and the inhibition of its degradation. Although the pathogenesis remains unclear, excessive accumulation of the extracellular matrix (ECM) is believed to be associated with the TGF-ß/SMAD pathway. Zinc-alpha-2-glycoprotein (ZAG) inhibits TGF-ß-mediated epithelial-to-mesenchymal transdifferentiation and impacts skin barrier functions. In this study, we investigated the potential of a small ZAG-derived peptide against hypertrophic scars and keloids. METHODS: The study examined cell proliferation and mRNA expression of collagen types I and III in human dermal fibroblast (HDF) cell lines and keloid-derived fibroblasts (KF) following ZAG peptide treatment. A rat incisional wound model was used to evaluate the effect of ZAG peptide in scar tissue. RESULTS: Significantly lower mRNA levels of collagen types I and III were observed in ZAG-treated fibroblasts, whereas matrix metalloproteinase (MMP)-1 and MMP-3 mRNA levels were significantly increased in HDFs and KFs. Furthermore, ZAG peptide significantly reduced protein expression of collagen type I and III, TGF-ß1, and p-Smad2/3 complex in KFs. Rat incisional scar models treated with ZAG peptide presented narrower scar areas and reduced immature collagen deposition, along with decreased expression of collagen type I, α-SMA, and p-Smad2/3. CONCLUSION: ZAG peptide effectively suppresses the TGF-ß and p-Smad2/3 pathway and inhibits excessive cell proliferation during scar formation, suggesting its potential therapeutic implications against keloids and hypertrophic scars.

The Immunomodulatory Power of Dupilumab: -Implications for Keloid Scar Treatment.

Keloids are pathologic responses to cutaneous injury. Current treatments, such as topical and intralesional steroids and even surgical excision, have limited efficacy, creating a demand for improved therapies. Our study explores the functioning of dupilumab, an interleukin-4 and inter-leukin-13 signaling pathway inhibitor, in this context. We have reviewed the literature for using dupilumab to treat keloids, evaluating safety and efficacy and offering recommendations for its application. We searched PubMed and Google Scholar using "Dupilumab" and "Keloid" as keywords. To ensure relevance, we limited the search to English language publications of 2018-2023. Dupilumab exhibited efficacy in keloid treatment, with notable improvements in patients. One patient reported a 50% reduction in the fibrotic plaque and complete resolution of smaller keloids without adverse effects. Two other patients reported successful stabilization and reduction in keloids following dupilumab therapy; however, the 12-week treatment demonstrated no response or reduction in post-treatment size or height of keloidals, with disease progression observed in one patient. One report discouraged the use of dupilumab for keloids due to limited positive responses. Considering dupilumab as the last therapeutic option to treat keloids may benef patients resistant to standard therapies and/or those highly motivated to reduce keloids.

The fibroblast heterogeneity across keloid, normal and tumor samples from single-cell resolution.

Keloids are defined as a benign dermal fibroproliferative disorder, with excessive fibroblast proliferation, and excessive overproduction of collagen. Although the heterogeneity during keloid development has been extensively studied, the heterogeneity across different skin states is still unclear. So, a global comparison across skin states is needed. In this study, we collected samples from 5 states of skin, including melanoma, cutaneous squamous cell carcinoma, keloid skin, scar skin, and healthy control samples. The heterogeneity of cell types and subtypes was analyzed and compared across 5 states, and we observed significant differences among them. Our results showed a cancer-like fibroblast, which is not in normal samples, may play an important role in antigen processing and presentation. We also noticed that the mesenchymal fibroblast increased in keloid samples, which highly expressed POSTN. And POSTN may participate in epithelial-mesenchymal transition and collagen overexpression to promote keloid growth. These findings help to understand the alteration among different skin states and provide potential genetic basis for keloid therapies.

Development of huge keloid at donor site and recurrent keloid at graft site after excision of pubic keloid followed by split-thickness skin graft: A case report.

INTRODUCTION: Keloids are the result of abnormal tissue scarring that occur after skin injuries leading to pain, psychological distress, and impaired quality of life. Despite the high recurrence rate after surgical treatment, excision is often inevitable for symptom control. PATIENT CONCERNS: A 32-year-old female presented with a huge keloid on the pubic area accompanied by severe pain, pruritus, and infectious discharge. She also had multiple keloids on her chest and shoulders, indicating a strong predisposition to keloid formation. INTERVENTIONS: While high potential for recurrence was anticipated, surgical excision was inevitable for symptom control. Complete keloid excision followed by split-thickness skin graft was performed. DIAGNOSIS: Pathological report revealed keloid accompanied by ruptured epidermal inclusion cyst. OUTCOMES: Although postoperative care was highly recommended for prevention of keloid recurrence, the patient refused any additional management due to her financial difficulties. At postoperative 8 months, mild degree of keloid or hypertrophic scar at marginal area of the graft was observed, suggesting the potential sign of keloid recurrence. The patient voluntarily discontinued the outpatient follow-up for 2 years, and then returned with huge keloid not only at the graft site but also at the donor site. CONCLUSION: Keloid with inflamed epidermal inclusion cyst can cause severe pain where surgical excision is unavoidable, regardless of the high potential for recurrence. Additional postoperative care is necessary to prevent recurrence. Furthermore, attempts to minimize new keloid formation at the donor site after split-thickness skin graft, such as thin skin harvest or selecting the scalp as the donor site, should be considered.

Development of Postsurgical Pyoderma Gangrenosum with New Keloid after Keloid Resection.

ABSTRACT: Keloids are a dermal fibroproliferative disorder and can arise from trauma, acne, vaccination, and herpes zoster. Pyoderma gangrenosum (PG) is a painful ulcerative skin disorder that is associated with neutrophilic dysfunction. However, the pathophysiologies of keloids and PG are not fully understood. The authors encountered an unusual case of a 24-year-old woman who presented with an anterior chest keloid that bore an ulcer. The keloid was resected along with the ulcer, and histology revealed the ulcer to be a neutrophilic PG ulcer. A year after surgery, another ulcer developed in the scar. The ulcer met the PARACELSUS criteria of a postsurgical PG ulcer. After treatment with systemic prednisone and adalimumab for 250 days, the ulcer re-epithelialized. However, relapsed keloids were then observed at the PG site. Corticosteroid taping may be the safest therapy for patients with a history of PG. Conversely, if there is suspicion that a patient is prone to keloid development, diagnostic biopsies and surgical management of PG ulcers should be avoided or conducted with care.

Effectiveness of postoperative superficial radiotherapy following the keloid-cross-flap surgery for auricular keloid: A prospective cohort study.

BACKGROUND AND PURPOSE: Retaining partial keloid skin to make cross flaps (keloid-cross-flap surgery) is a modification of the core excision. This study aimed to compare the effectiveness of superficial radiotherapy versus compression therapy after keloid-cross-flap surgery. MATERIALS AND METHODS: In this prospective cohort study, auricular keloid patients were consecutively screened from January 2019 to December 2021. They underwent keloid-cross-flap surgery and then enter either the superficial radiotherapy or the compression treatment group. The primary outcome was the one-year keloid recurrence rate. Secondary outcomes included: non-completion rate of adjuvant treatment; Patient and Observer Scar Assessment Scale (POSAS) scores and auricular aesthetics scores, evaluated by a four-point Likert scale (1 = poor to 4 = excellent) of non-recurring patients. Propensity score matching (PSM) was used to eliminate potential confounding factors. RESULTS: 123 patients were included in the superficial radiotherapy group and 128 in the compression treatment group. Non-completion rate was significantly higher in the compression treatment group (17.97 %), while the loss rate was comparable between the two groups. Overall, 13 patients (13.54 %) relapsed in superficial radiotherapy group, while 22 patients (25.58 %) in compression group (p < 0.05). After PSM, 59 patients in each group were analyzed, and the recurrence rate was lower in the superficial radiotherapy group (13.56 %). Of relapse-free patients, no significant difference was found in PSAS scores, OSAS scores or aesthetic scores between the two groups. CONCLUSION: Keloid-cross-flap surgery could provide favorable morphologic repair of the auricular keloid, and postoperative superficial radiotherapy shows higher compliance and lower recurrence rate comparing to compression treatment.

Remdesivir alleviates skin fibrosis by suppressing TGF-ß1 signaling pathway.

Fibrotic skin diseases, such as keloids, are pathological results of aberrant tissue healing and are characterized by overgrowth of dermal fibroblasts. Remdesivir (RD), an antiviral drug, has been reported to have pharmacological activities in a wide range of fibrotic diseases. However, whether RD function on skin fibrosis remains unclear. Therefore, in our study, we explored the potential effect and mechanisms of RD on skin fibrosis both in vivo and in vitro. As expected, the results demonstrated that RD alleviated BLM-induced skin fibrosis and attenuates the gross weight of keloid tissues in vivo. Further studies suggested that RD suppressed fibroblast activation and autophagy both in vivo and in vitro. In addition, mechanistic research showed that RD attenuated fibroblasts activation by the TGF-ß1/Smad signaling pathway and inhibited fibroblasts autophagy by the PI3K/Akt/mTOR signaling pathway. In summary, our results demonstrate therapeutic potential of RD for skin fibrosis in the future.