The Use of Chemotherapeutics for the Treatment of Keloid Scars

Comparing Combination Triamcinolone Acetonide and 5-Fluorouracil with Monotherapy Triamcinolone Acetonide or 5-Fluorouracil in the Treatment of Hypertrophic Scars: A Systematic Review and Meta-Analysis

BACKGROUND

Keloids and hypertrophic scars cause physical and psychosocial problems. A combination of 5-fluorouracil (5-FU) and triamcinolone acetonide (TAC) may enhance the treatment of pathologic scars, although the evidence base is limited. The authors compared the efficacy and complication rates of combination intralesional TAC and 5-FU with those of monotherapy intralesional TAC or 5-FU for the treatment of keloids and hypertrophic scars.

METHODS

Embase, MEDLINE, and CENTRAL were searched by two independent reviewers. The primary outcome was treatment efficacy (51% to 100% improvement). Study quality and risk of bias were assessed using the Cochrane risk of bias tool.

RESULTS

Of 277 articles screened, 13 studies were included, comprising 12 randomized control trials and one nonrandomized study. Six studies compared combination intralesional therapy versus monotherapy 5-FU, and nine studies compared combination intralesional therapy versus monotherapy TAC. The combined group demonstrated superior objective treatment efficacy compared with the monotherapy TAC group (OR, 3.45; 95% CI, 2.22 to 5.35; I 2 = 0%; P < 0.00001) and monotherapy 5-FU group (OR, 4.17; 95% CI, 2.21 to 7.87; I 2 = 0%; P < 0.0001). Telangiectasia was less frequent in combination therapy (OR, 0.24; 95% CI, 0.11 to 0.52; I 2 = 0%; P = 0.0003) compared with monotherapy TAC.

CONCLUSIONS

Combined intralesional TAC and 5-FU administration demonstrated superior treatment efficacy outcomes compared with monotherapy TAC or 5-FU. Patient-reported outcome measures should be incorporated in the design of future research to justify clinical recommendations.

CLINICAL RELEVANCE STATEMENT

Combined TAC and 5-FU has demonstrated superior treatment efficacy outcomes compared to monotherapy TAC or 5-FU in the treatment of hypertrophic scars and keloids.

Identifying potential drug targets for keloid: A Mendelian randomization study

Keloids are a skin fibrosis disease characterized by troublesome symptoms, a varying degree of recurrence and inevitable side effects from treatments. Thus, identifying their drug targets is necessary. A two-sample MR analysis was conducted using proteins from the intersection of the deCODE database and "The Druggable Genome and Support for Target Identification and Validation in Drug Development" as the exposure variable. The outcome variable was based on recently published GWAS of keloids. SMR and colocalization analysis was employed to distinguish pleiotropy from linkage. Candidate targets underwent drug target analysis. The primary findings were validated through scRNA-seq data, Western Blot and immunofluorescence staining on keloids. Seven proteins were identified as potential drug targets for keloids. Among these proteins, HHIP, NTM, KLKB1, and CRIPTO showed positive correlations with keloids, while PLXNC1, SCG3 and PDGF-D exhibited negative correlations. Combined with the scRNA-seq data, NTM, PLXNC1, and PDGF-D were found highly expressed in the fibroblasts. NTM showed a significant increase in keloids as compared to normal scars. In accordance with the analysis, higher levels of protein expression of NTM in keloids compared to normal skin was observed. The identified proteins may be appealing drug targets for keloids treatment with a special emphasis on NTM.

Pharmacotherapy for Keloids and Hypertrophic Scars

Keloids (KD) and hypertrophic scars (HTS), which are quite raised and pigmented and have increased vascularization and cellularity, are formed due to the impaired healing process of cutaneous injuries in some individuals having family history and genetic factors. These scars decrease the quality of life (QOL) of patients greatly, due to the pain, itching, contracture, cosmetic problems, and so on, depending on the location of the scars. Treatment/prevention that will satisfy patients' QOL is still under development. In this article, we review pharmacotherapy for treating KD and HTS, including the prevention of postsurgical recurrence (especially KD). Pharmacotherapy involves monotherapy using a single drug and combination pharmacotherapy using multiple drugs, where drugs are administered orally, topically and/or through intralesional injection. In addition, pharmacotherapy for KD/HTS is sometimes combined with surgical excision and/or with physical therapy such as cryotherapy, laser therapy, radiotherapy including brachytherapy, and silicone gel/sheeting. The results regarding the clinical effectiveness of each mono-pharmacotherapy for KD/HTS are not always consistent but rather scattered among researchers. Multimodal combination pharmacotherapy that targets multiple sites simultaneously is more effective than mono-pharmacotherapy. The literature was searched using PubMed, Google Scholar, and Online search engines.

Effective keloid management using a combinatorial continuous-wave and repeat fractionated ablative CO2 laser regimen

BACKGROUND

Keloids are benign proliferative scars that form as a result of dysregulated growth and collagen deposition in response to cutaneous injury. Laser therapies have emerged as promising options for the treatment of keloids, with performance varying by laser type and lesion characteristics.

PURPOSE

To assess the combined continuous wave and repetitive fractionated CO2 laser treatment of keloids.

METHODS

A retrospective chart review of 22 cases of keloid scars treated with combined CO2 laser modes. A single session of continuous wave followed by five sessions of fractional delivery. Efficacy was assessed using the Patient and Observer Scar Assessment Scale (POSAS) and the Vancouver Scar Scale. The Numeric Rating Scale was used to assess patient satisfaction and pain.

RESULTS

Most patients were female (77.3%) with skin type IV (72.7%), age was 24.3 ± 9.3 years, most keloids were located on the earlobe (56.5%) or arm or hand (17.4%), size ranged from 5 to 10 cm, and time since injury ranged from 3 months to 35 years. No serious adverse events were reported. At 6 months, significant improvements from baseline occurred in all characteristics, scar color (4.8 ± 2.8 to 1.9 ± 1.1), rigidity (5.0 ± 2.8 vs. 5.4 ± 2.8), thickness (5.4 ± 2.8 vs. 2.0 ± 1.1), and irregularity (5.9 ± 2.4 vs. 1.9 ± 0.9). The Vancouver scores followed a similar trend. Patient-rated overall improvement from 37 ± 17.6 at baseline to 16.1 ± 8.5 at 6 months, and improvement in associated pain and pruritus.

CONCLUSION

Combination of two ablative laser delivery modes within a single laser platform provided for effective and safe keloid management and left patients highly satisfied.

Recurrence rates in the treatment of keloids and hypertrophic scars with intralesional triamcinolone combined with other intralesional agents

Hypertrophic scars (HTS) and keloids are pathologic scars that are products of a wound healing pathway error attributed to genetic and inflammatory causes (Leventhal et al., Arch Facial Plast Surg 8(6):362-368. https://doi.org/10.1001/archfaci.8.6.362 , 2006). Methods of pathologic scar treatment include intralesional agents, cryotherapy, surgical excision, pressure dressings, topical agents, laser resurfacing, radiotherapy, and other investigational therapies (Leventhal et al. 2006). The recurrence of pathologic scar is high across all treatment modalities, including the use of intralesional agents (Trisliana Perdanasari et al., Arch Plast Surg 41(6):620-629. https://doi.org/10.5999/aps.2014.41.6.620 , 2014). In the treatment of pathologic scar, combination approaches using intralesional agents, such as triamcinolone (TAC), 5-fluorouracil (5FU), verapamil (VER), bleomycin (BLM), and botulinum toxin (BTX), are superior therapies when compared to monotherapy (Yosipovitch et al., J Dermatol Treat 12(2):87-90. https://doi.org/10.1080/095466301317085363 , 2001; Yang et al., Front Med 8:691628. https://doi.org/10.3389/fmed.2021.691628 , 2021; Sun et al., Aesthetic Plast Surg 45(2):791-805. https://doi.org/10.1007/s00266-019-01570-8 , 2021). This review assesses recurrence and the reporting of recurrence in pathologic scar after treatment with intralesional triamcinolone (TAC) in combination with another intralesional agent. A literature review was conducted using research journals from PubMed using the following search terms: [(keloid) AND (triamcinolone) AND (combination) AND (intralesional)], as well as [(keloid) AND (triamcinolone) AND (combination)]. Articles were reviewed and included if the article analyzed  or compared intralesional agents for pathologic scar treatment within the last 10 years. The average follow-up period of included articles (n = 14) that utilized combination intralesional therapy (TAC-X) was approximately 11 months (range 1-24 months). Consistent recurrence rate reporting across studies was lacking. The combination agent with the highest recurrence rate was TAC-5FU (23.3%). The range of reported recurrence rates was 7.5-23.3%. Six studies using various intralesional combination regimens reported 0% recurrence over the follow-up period (TAC-5FU, TAC-BTX, TAC-BLM, TAC-CRY). Three studies did not report recurrence rates. While the efficacy of combination therapy is typically assessed via scar scales, the assessment of recurrence across studies of combination therapy is inconsistent and inadequate, with truncated follow-up periods. While scar recurrence can take place during 1-year post-treatment, long-term follow-up (18-24 months) is needed to characterize recurrence in the treatment of pathologic scar using various intralesional agents. Long-term follow-up periods allow patients to receive accurate prognostic information regarding recurrence after combination intralesional therapy. There are limitations to this review in that comparisons were made across studies with varying outcome variables, including scar size, injection concentration and interval, and follow-up period. Standardized follow-up periods and recurrence rate reporting are integral to furthering the understanding of these therapies and enhancing patient care.

An Overview of Recent Developments in the Management of Burn Injuries

According to the World Health Organization (WHO), around 11 million people suffer from burns every year, and 180,000 die from them. A burn is a condition in which heat, chemical substances, an electrical current or other factors cause tissue damage. Burns mainly affect the skin, but can also affect deeper tissues such as bones or muscles. When burned, the skin loses its main functions, such as protection from the external environment, pathogens, evaporation and heat loss. Depending on the stage of the burn, the patient's condition and the cause of the burn, we need to choose the most appropriate treatment. Personalization and multidisciplinary collaboration are key to the successful management of burn patients. In this comprehensive review, we have collected and discussed the available treatment options, focusing on recent advances in topical treatments, wound cleansing, dressings, skin grafting, nutrition, pain and scar tissue management.

Efficacy and safety of the innovative cold atmospheric-pressure plasma technology in the treatment of keloid: A randomized controlled trial

BACKGROUND

Keloid (KD) treatment is challenging for both physicians and patients. It can be functional debilitating and psychologically distressing. Available current therapeutics modalities give inconsistently effective results.

OBJECTIVES

To evaluate the efficacy and safety of innovative cold atmospheric plasma (CAP) technology in the treatment of keloid.

METHODS

This prospective, randomized control trial, the assessor-blinded trial, includes 18 patients with keloids. The keloid lesion was divided into two halves. One side was randomly treated with CAP technology biweekly on the same treated side for five sessions with a follow-up 30 days after finishing the final treatment. Another half was left untreated as a control. Efficacy assessment using POSAS, VSS, Patients' satisfaction scale, Antera 3D® skin imaging system. The safety assessment using VAS and adverse effects monitoring was completed.

RESULTS

Objective assessment using Antera 3D® skin imaging system (Miravex, Dublin, Ireland) showed statistically significant improvement (p-value <0.05) on the treated side compared with the untreated side in all parameters, color, melanin, hemoglobin, texture, except for volume. POSAS, patient, and observer overall opinion score, and patient and observer total score in the summary of all rated characteristics, comparing the treated and untreated areas, showed a statistically significant reduction in all parameters after two treatments (*p-value <0.05). VSS showed statistically significant improvement after the second treatment and continued to the last follow-up. Most patients rated satisfaction scales up to 72.2% as moderate improvement, 11.1% as great improvement, 11.1% as slight improvement, and 5.6% as no change. The adverse effect was only a small scab in one patient.

CONCLUSION

CAP technology could be considered an alternative treatment for keloid offering mild-to-moderate improvement with minimal side effects.

Evaluating serum level of thymidylate synthase in post burn keloid patients before and after intralesional injection of 5-fluorouracil

Background

Keloids are fibrous lesions formed at the site of trauma due to types I and III collagen irregular production. The presence of thymidylate synthase (TS) is a must for DNA synthesis and repairs causing cell death. 5-fluorouracil (5-FU) is a fluorinated pyrimidine analogue acting as an anti-metabolic agent that inhibits thymidylate synthase and interferes with ribo-nucleic acid (RNA) synthesis.

Objectives

we aimed to evaluate the level of thymidylate synthase in post burn keloid patients before and after intralesional injection of 5-fluorouracil.

Methods

The study included 20 keloid patients and 20 healthy subjects as a control. Serum TS was estimated using commercially available enzyme-linked immunosorbent assay (ELISA) kits before and after treatment with 5-fluorouracil.

Results

There was a statistically significant difference in TS levels before and after 5-FU treatment (p < 0.05). Also, results have shown that 5-FU injection has good satisfactory results in treatment of keloid causing reduction in scar volume and symptoms improvement (90% of the patients improved). On the other hand, there was no statistically significant difference in TS levels and the outcomes of the treatment.

Conclusion

Our findings suggest that intralesional 5-FU injection in keloid has very satisfactory results. However, thymidylate synthase enzyme has a minimal role in evaluating the treatment of keloid, so further studies are required to elaborate the relation between this enzyme and keloid scars.

Tauroursodeoxycholic Acid Decreases Keloid Formation by Reducing Endoplasmic Reticulum Stress as Implicated in the Pathogenesis of Keloid

Keloids are a common form of pathologic wound healing and are characterized by an excessive production of extracellular matrix. This study examined the major contributing mechanism of human keloid pathogenesis using transcriptomic analysis. We identified the upregulation of mitochondrial oxidative stress response, protein processing in the endoplasmic reticulum, and TGF-β signaling in human keloid tissue samples compared to controls, based on ingenuity pathway and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Electron microscopic examinations revealed an increased number of dysmorphic mitochondria and expanded endoplasmic reticulum (ER) in human keloid tissue samples than that in controls. Western blot analysis performed using human tissues suggested noticeably higher ER stress signaling in keloids than in normal tissues. Treatment with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor, significantly decreased scar formation in rabbit models, compared to normal saline and steroid injections. In summary, our findings demonstrate the contributions of mitochondrial dysfunction and dysregulated ER stress signaling in human keloid formation and the potential of TUDCA in the treatment of keloids.

Update on management of keloid and hypertrophic scars: A systemic review

Numerous therapeutic strategies have been described for prevention and reduction of hypertrophic scars and keloids, but none of the treatments is effective in all patients. No universal consensus in treatment regimen has been established, and there is limited evidence-based literature to guide the correct management. The process of scar development is complex and requires deeper understanding of the molecular mechanisms that cause their development and recurrences. Despite many available modes of targeting keloid and hypertrophic scars, yet they remain an ongoing challenge to patients and clinicians. To date, no one therapy has been universally accepted as the gold standard for the treatment of all excessive scars nor has the capability of complete scar resolution The search of literature included peer-reviewed articles including clinical trials and scientific reviews. Literature was identified from electronic databases (MEDLINE/PubMed) through May 2021 and references of respective articles and only the articles published in English language were included.

Current Advances in Hypertrophic Scar and Keloid Management

Hypertrophic scars and keloids are caused by excessive tissue response to dermal injury due to local fibroblast proliferation and collagen overproduction. This response occurs because of pathologic wound healing due to dysregulation in the inflammatory, proliferative, and/or remodeling phase. Patients with hypertrophic scars or keloids report reduced quality of life, physical status, and psychological health. Hypertrophic scars or keloids will develop in 30 to 90% of individuals, and despite their prevalence, treatment remains a challenge. Of the treatments currently available for hypertrophic scars and keloids few have been adequately supported by studies with appropriate experimental design. Here, we aim to review the available literature to provide up-to-date information on the etiology, epidemiology, histology, pathophysiology, prevention, and management options available for the treatment of hypertrophic scars and keloids and highlight areas where further research is required.

LINC01116 regulates proliferation, migration, and apoptosis of keloid fibroblasts by the TGF-β1/SMAD3 signaling via targeting miR-3141

BACKGROUND

Keloids are benign fibroproliferative skin tumors. Long non-coding RNAs (lncRNAs) have been implicated in the pathogenesis of keloid formation. In this paper, we explored the precise actions of LINC01116 in keloid formation.

METHODS

The targeted relationship between microRNA (miR)-3141 and LINC01116 or transforming growth factor β1 (TGF-β1) was verified by dual-luciferase reporter, RNA immunoprecipitation (RIP), and RNA pull-down assays. The expression levels of LINC01116, miR-3141, TGF-β1, and SMAD family member 3 (SMAD3) were gauged by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Cell proliferation, migration, and apoptosis were assessed by the Cell Counting Kit-8 (CCK-8) assay, wound-healing assay, and flow cytometry, respectively. Animal studies were used to assess the role of LINC01116 in the subcutaneous keloid growth in vivo.

RESULTS

Our data showed that LINC01116 targeted miR-3141 by directly binding to miR-3141. LINC01116 was up-regulated and miR-3141 was down-regulated in human keloid tissues and fibroblasts. LINC01116 knockdown or miR-3141 overexpression suppressed keloid fibroblast proliferation, migration, and promoted cell apoptosis. Moreover, miR-3141 was a downstream mediator of LINC01116 function. MiR-3141 regulated the TGF-β1/SMAD3 signaling by directly targeting TGF-β1. Furthermore, TGF-β1 was identified as a direct and functional target of miR-3141. LINC01116 regulated the TGF-β1/SMAD3 signaling through miR-3141. Additionally, LINC01116 knockdown diminished the subcutaneous keloid growth in vivo.

CONCLUSION

Our findings demonstrated a novel mechanism, the miR-3141/TGF-β1/SMAD3 regulatory pathway, at least partially for the oncogenic role of LINC01116 in keloid formation.

Management of keloid scars: noninvasive and invasive treatments

Scars vary from mature linear scars to abnormal excessive scars such as hypertrophic scars and keloid scars. Keloid scars are fibro-proliferative disease entities that reflect an abnormal process of wound healing. They can cause pain, itching, stiffness, and psychological distress, all of which can affect quality of life. Various treatment options have been advocated as ways to prevent and treat keloid scars. These include noninvasive treatments such as use of silicone gel sheeting and compression therapy, and invasive treatments such as intralesional corticosteroid injections, surgery, and radiotherapy. Novel treatments include chemotherapy, immunotherapy, and anti-inflammatory therapies. Unfortunately, keloids continue to pose a significant challenge due to the lack of efficacious treatments. Therefore, clinicians should be familiar with various therapeutic options and apply the most suitable treatment plan for patients. In this review, we introduce the current therapeutic options for the management of keloid scars.

Emerging and Novel Therapies for Keloids: A compendious review

Keloids are abnormal fibroproliferative scars with aggressive dermal growth expanding beyond the borders of the original injury. Different therapeutic modalities, such as corticosteroids, surgical excision, topical silicone gel sheeting, laser therapy, cryotherapy, photodynamic therapy and radiotherapy, have been used to treat keloids; however, none of these modalities has proven completely effective. Recently, researchers have devised several promising anti-keloid therapies including anti-hypertensive pharmaceuticals, calcineurin inhibitors, electrical stimulation, mesenchymal stem cell therapy, microneedle physical contact and ribonucleic acid-based therapies. The present review summarises emerging and novel treatments for keloids. PubMed^® (National Library of Medicine, Bethesda, Maryland, USA), EMBASE (Elsevier, Amsterdam, Netherlands) and Web of Science (Clarivate Analytics, Philadelphia, Pennsylvania, USA) were searched for relevant literature published between January 1987 to June 2020. A total of 118 articles were included in this review. A deeper understanding of the molecular mechanisms underlying keloid scarring pathogenesis would open further avenues for developing innovative treatments.

Treatment of Small Keloids Using Intralesional 5-fluorouracil and Triamcinolone Acetonide versus Intralesional Bleomycin and Triamcinolone Acetonide

BACKGROUND: The aberration of wound healing leads to scar formation in the form of hypertrophic scars and keloids. Various modalities with variable results have been used in the treatment of keloids. OBJECTIVE: We sought to evaluate outcomes in the treatment of small keloids with the combination of intralesional 5-fluorouracil (5-FU) and triamcinolone acetonide versus intralesional bleomycin and triamcinolone acetonide. DESIGN: Sixty clinically diagnosed keloid lesions in 40 patients aged 18 to 60 years were divided equally into Groups A (n=30) and B (n=30). The combination of intralesional 5-FU and triamcinolone acetonide (TAC) was given to Group A and the combination of intralesional bleomycin and triamcinolone acetonide was given to Group B. Treatment was repeated in both groups at three-week intervals until keloid flattening was achieved or a maximum of 10 treatments were completed. Before treatment, the lesions were assessed using the Vancouver Scar Scale and their size was measured using vernier calipers. RESULTS: In Group A, 15 (50%) keloids showed an excellent response, 10 (33.33%) keloids showed a good response, three (10%) keloids showed a fair response, and two (6.66%) keloids showed a poor response. In Group B, 23 (76%) keloids showed an excellent response, three (10%) keloids showed a good response, two (6.66%) keloids showed a fair response, and two (6.66%) keloids showed a poor response. CONCLUSION: Patient response regarding treatment duration, flattening of lesions, improvements in the Vancouver Scar Scale score, and recurrence rates were statistically significant in Group B. A greater improvement in the signs and symptoms of keloids (with respect to cosmetic problems, restriction of movement, and tenderness) was observed in the patients treated with a combination of intralesional bleomycin and triamcinolone acetonide compared to those treated with a combination of intralesional 5-FU and triamcinolone acetonide.

Treatment of hypertrophic scars and keloids using an intralesional 1470 nm bare-fibre diode laser: a novel efficient minimally-invasive technique

Hypertrophic and keloid scars result from abnormal wound healing and can have a variable response to a number of available treatment modalities. The evolution of laser treatments in recent years has shown a wide range of clinical applications including their use in the treatment of scars. We investigated the effectiveness of a 1470 nm diode laser using an intralesional optical fibre delivery device in the treatment of hypertrophic and keloid scars. We evaluated its safety and efficacy as a novel and minimally invasive treatment alternative for scar modulation and volume reduction. A prospective cohort study was performed involving 21 patients with hypertrophic scars (HS) (n = 9) and keloids (n = 12) resulting from various aetiology. Patients were treated with one to three treatment sessions. Comprehensive evaluations were performed using the Vancouver Scar Scale, Doppler ultrasound, Cutometer, Mexameter and PeriCam PSI. Scar thickness was reduced by an average of 0.308 ± 0.138 cm (p < 0.001). In particular the two subgroups showed a significant 27.7% and 28.2% reduction in scar thickness of HS and Keloids, respectively. Scar firmness showed a significant improvement of 1.2% (p < 0.05) for HS, though for keloids this was 0.4% (p = 0.26). Keloids had a significant reduction in pigmentation at 21.3%. Blood perfusion had a significant reduction of 29.6% in HS and 22.7% in Keloids. Overall VSS total score improvement of 42% in the HS and at 37.9% in the Keloid subgroup. No adverse events such as hypo/hyperpigmentation, skin infection, or recurrence were reported. This study shows that the intralesional 1470 nm bare-fibre diode laser significantly improved hypertrophic and keloid scars based on both subjective and objective analyses and supports this type of laser therapy as a safe and effective minimally-invasive treatment option.

[Application status and prospect of botulinum toxin A in otorhinolaryngological treatment]

Botulinum toxin A is a kind of neurotoxin produced by clostridium botulinum, and has been applied for nearly thirty years in China.The target of BTX-A is to selectively cleave the synaptosome-associated protein of 25 KD molecular mass, commonly abbreviated SNAP-25, thereby inhibiting neurotransmitter release and causing chemodenervation. The potential application of botulinum toxin A in treating the spasmodic dysphonia, hemifacial spasm, tinnitus, rhinitis has been confirmed both in clinical practice and previous studies. This paper is to review comprehensively the application status and the prospect of botulinum toxin A in otorhinolaryngological treatment.

Keloids: Current and emerging therapies

Keloids are pathological scars that grow over time and extend beyond the initial site of injury after impaired wound healing. These scars frequently recur and rarely regress. They are aesthetically disfiguring, can cause pain, itching, discomfort as well as psychological stress, often affecting quality of life. Many treatment modalities, including surgical and non-surgical, have been explored and have been reported to be beneficial; however, none have been absolutely satisfactory or optimal for the treatment of all keloid subtypes to date. This poses a major challenge to clinicians. Often, a combinational therapeutic approach appears to offer the best results with higher patient satisfaction compared to monotherapy. The aetiopathogenesis of keloids is not fully elucidated; however, with recent advances in molecular biology and genetics, insight is being gained on the complex process of scar formation and hence new therapeutic and management options for keloids. In this paper, we explore the literature and summarise the general concepts surrounding keloid development and review both current (corticosteroids, surgical excision, silicone-based products, pressure therapy, radiotherapy, cryotherapy, laser therapy, imiquimod and 5-fluorouracil) and emerging (stem cell therapy, mitomycin C, verapamil, interferons, bleomycin, botulinum toxin type A and angiotensin-converting enzyme inhibitors) treatments. Increased knowledge and understanding in this area may potentially lead to the discovery and development of novel therapeutic options that are more efficacious for all keloid types.

LAY SUMMARY

Keloids are problematic scars that are difficult to treat and manage. The aetiopathogenesis of keloids is not clear; however, recent advances in molecular biology and genetics are beginning to shed light on the underlying mechanisms implicated in keloid scar formation which will hopefully lead to the development of treatment options for all keloid types. This review summarises current and emerging therapies.

In Vitro and Ex Vivo Models for Functional Testing of Therapeutic Anti-scarring Drug Targets in Keloids

Significance: Keloids are benign fibro-proliferative raised dermal lesions that spread beyond the original borders of the wound, continue to grow, rarely regress, and are the most common in pigmented individuals after an abnormal wound healing response. The current treatment failure and respective challenges involved highlighting the underlying issue that the etiopathogenesis of keloids is still not well understood. Disease models are required to better understand the disease pathogenesis. It is not possible to establish keloids in animals because of the uniqueness of this disease to human skin. To address this challenge, along these lines, non-animal reproducible models are vital in investigating molecular mechanisms of keloid pathogenesis and therapeutics development. Recent Advances: Various non-animal models have been developed to better understand the molecular mechanisms involved in keloid scarring and aid in identifying and evaluating the therapeutic potential of novel drug candidates. In this scenario, the current review aims at describing in vitro monocultures, co-cultures, organotypic cultures, and ex vivo whole skin keloid tissue organ culture models. Critical Issues and Future Directions: Current treatment options for keloids are far from securing a cure or preventing disease recurrence. Identifying universally accepted effective therapy for keloids has been hampered by the absence of appropriate disease model systems. Animal models do not accurately mimic the disease, thus non-animal model systems are pivotal in keloid research. The use of these models is essential not only for a better understanding of disease biology but also for identifying and evaluating novel drug targets.

MiR-152-3p regulates cell proliferation, invasion and extracellular matrix expression through by targeting FOXF1 in keloid fibroblasts

Emerging evidence has revealed that microRNAs (miRNAs) play critical roles in keloid pathogenesis. However, potential molecular mechanism of keloid formation remains unclear. In the present study, our findings showed that miR-152-3p mRNA expression level was notably up-regulated in keloid tissues and keloid fibroblasts compared with that of normal skin tissues and normal skin fibroblasts, respectively. Furthermore, miR-152-3p inhibition remarkably suppressed cell proliferation, which was increased by miR-152-3p overexpression. Cell invasion was also significantly decreased by miR-152-3p inhibition, whereas was increased by miR-152-3p overexpression. The mRNA and protein expression levels of extracellular matrix components including type I collagen, type III collagen and fibronectin were decreased by miR-152-3p inhibition, but were increased by miR-152-3p overexpression. In addition, results of dual-luciferase reporter assay indicated that FOXF1 is a direct target of miR-152-3p. FOXF1 overexpression significantly inhibits cell proliferation, invasion, and extracellular matrix in keloid fibroblasts, and the suppressive effects of miR-152-3p mimic on these functions were notably partly reversed by FOXF1 overexpression. Taken together, these findings indicated that miR-152-3p regulates cell proliferation, invasion and extracellular matrix expression through targeting FOXF1 in keloid fibroblasts, suggesting that miR-152-3p is a novel and promising molecular target for keloid treatment.

Original Method to Repigment Achromic Laser Tattoo Removal Scars

Laser tattoo removal is expensive, painful, and time-consuming. Even with the use of the right laser equipment, it is often impossible to eliminate all pigments. Incomplete tattoo removal, one of the undesired effects of laser treatment, is widely disseminated in the media and accepted by most patients. However, few patients know that laser tattoo removal can cause permanent scars. Some patients who develop achromic scars can feel disappointed with the results of laser tattoo removal and take legal action against the physician responsible for the treatment. This paper describes our experience with a drug delivery treatment called MMP® (“Microinfusão de Medicamentos na Pele,” Portuguese acronym for “Microinfusion of Drugs in the Skin”) that repigments and improves the final esthetic results of achromic laser tattoo removal scars.

Analysis of Keloid Response to 5-Fluorouracil Treatment and Long-Term Prevention of Keloid Recurrence

Keloids are benign fibroproliferative skin tumors that can cause disfigurement and disability. Although they frequently recur after excision or medical management and can affect 6 to 16 percent of African Americans, there is no gold standard therapy. Keloids are challenging to study because there are no animal or in vitro models of this disorder. This makes it very difficult to validate data from treated tissue samples or cells and develop targeted therapies for this disease. In this study, the authors demonstrate that intralesional 5-fluorouracil injection after keloid excision prevents recurrence for 2 years, with no reported adverse events. The authors analyze the expression of treated and untreated biopsy specimens of the same keloids in their native context to capture insights that may be missed by in vitro cell culture models and correct for intrakeloid variability. Random forest analysis of the microarray data dramatically increased the statistical power of the authors' results, permitting hypothesis-free creation of a gene expression profile of 5-fluorouracil-treated keloids. Through this analysis, the authors found a set of genes, including YAP1 and CCL-2, whose expression changes predict 5-fluorouracil therapy status and include genes that have not previously been associated with keloid biology and are of unknown function. The authors further describe keloid heterogeneity for the first time using multidimensional analysis of their microarray results. The methods and tools the authors developed in this research may overcome some of the challenges in studying keloids and developing effective treatments for this disease. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, V.

New technologies in global burn care - a review of recent advances

There have been truly incredible strides in the standard of burn care. The mortality from burn injuries has more than halved since the 1950s, making it hugely unique among major diseases of the developed world. There can be no doubt technology and technological advances have driven this process, dramatically improved every aspect of burn care, from the intensive care management, the surgical management, management of the healing wound to the post burn sequelae, specifically scar management. This review aims to identify key technological advances in burns, in both the developed and developing world, and evaluate their influence in the continued strategy to improve the standards of global burn care.

5-fu for problematic scarring: a review of the literature

Keloids and hypertrophic scars represent a common complaint for plastic surgeons. These scars often leave patients with severe morbidity due to their resistance to therapy. A variety of therapeutic options exist, yet none seem to offer a permanent solution, and scars frequently reoccur. The antineoplastic drug 5-fluorouracil (5-FU) has been shown to inhibit fibroblast proliferation in vitro and has been used as a treatment modality for these pathologic and problematic scars. We present a review of literature on treatment protocols, and on the efficacy and safety profile of this drug in the treatment of problematic scarring in terms of size reduction and symptom resolution. Current evidence suggests that 5-FU is effective in treating keloids and hypertrophic scars, but further research must be done to correlate therapeutic response with the age of the scar. In addition, larger randomized control trials must be conducted with longer follow up periods to assess recurrence rates with better accuracy.

Recent Understandings of Biology, Prophylaxis and Treatment Strategies for Hypertrophic Scars and Keloids

Hypertrophic scars and keloids are fibroproliferative disorders that may arise after any deep cutaneous injury caused by trauma, burns, surgery, etc. Hypertrophic scars and keloids are cosmetically problematic, and in combination with functional problems such as contractures and subjective symptoms including pruritus, these significantly affect patients’ quality of life. There have been many studies on hypertrophic scars and keloids; but the mechanisms underlying scar formation have not yet been well established, and prophylactic and treatment strategies remain unsatisfactory. In this review, the authors introduce and summarize classical concepts surrounding wound healing and review recent understandings of the biology, prevention and treatment strategies for hypertrophic scars and keloids.

Induction of apoptosis in nasal polyp-derived fibroblasts by bleomycin A5 in vitro

The present study aimed to evaluate the pro-apoptotic effects of bleomycin A5 on nasal polyp‑derived fibroblasts (NPDFs) and the underlying molecular mechanisms. Nasal polyp tissue was acquired from 10 patients during surgery and NPDFs were isolated from surgical tissues. Fibroblasts were identified using immunohistochemistry. Bleomycin A5 was used to treat NPDFs along a concentration gradient. Cell viability was evaluated using a Cell Counting Kit‑8 assay. A flow cytometric Annexin V‑fluorescein isothiocyanate/propidium iodide assay was used to determine the percentage of apoptotic NPDFs. The mRNA expression levels of apoptotic genes were determined by reverse transcription‑quantitative polymerase chain reaction and levels of proteins associated with apoptosis were determined by western blotting. The results indicated that bleomycin A5 was able to induce apoptosis in NPDFs in a dose‑dependent manner. NPDFs treated with bleomycin A5 were identified to contain significantly high amounts of the active forms of caspase‑3 and showed considerable cleavage of poly(ADP‑ribose) polymerase. The mRNA and protein expression levels of the pro‑apoptotic molecule Bcl‑2‑associated X protein were significantly higher in treated NPDFs than in untreated NPDFs. In contrast, the mRNA and protein expression of the anti‑apoptotic molecule B‑cell lymphoma 2 (Bcl‑2) was significantly lower in treated NPDFs. These results indicated that bleomycin A5 could induce apoptosis in primary NPDFs through activation of the Bcl‑2 family and caspase cascades in a time-, and concentration-dependent manner.

Autofluorescence of collagen fibres in scar

BACKGROUND/PURPOSE

Autofluorescence has become an important factor associated with diagnosis and treatment of many diseases.

METHODS

Full thickness skin grafts and scar biopsies were obtained from five volunteers. The normal skin or scar tissue paraffin-wax sections were stained with HE and the autofluorescence of collagen fibres was viewed under fluorescence microscopy.

RESULTS

In normal skin, the autofluorescence was showed in dermis, specifically in collagen fibres. There was very weak autofluorescence in epidermis. The spectrum was excited at 488 nm and the peak value of autofluorescence was significantly different between reticular layer (169.24±9.18) and papillar layer of dermis (103.91±15.23). In scar tissue, the autofluorescence was showed in collagen fibres and the peak value was 176.71±20.69. The structure of collagen fibres in normal skin or scar tissue was different in loose degree, thickness, boundle size, and morphology by their autofluorescence.

CONCLUSION

The different peak value of autofluorescence between scar and normal skin may due to the different density of collagen fibtes in them. This study may provide us a simple and effective assessment indicator and method for diagnosis and treatment of scar.

Combined effects of long-pulsed neodymium-yttrium-aluminum-garnet laser, diprospan and 5-fluorouracil in the treatment of keloid scars

Keloids are benign tumors that originate from scar tissues, but they usually overgrow beyond the original wounds. In a three-month single-center clinical trial, 69 patients were randomly divided into three groups. Patients in group 1 were treated with intralesional injection of diprospan (2 mg betamethasone disodium phosphate and 5 mg betamethasone dipropionate in 1 ml) with one-month intervals for three months. Patients in groups 2 and 3 were injected with a combination of 0.5 ml 5-fluorouracil (5-FU; 25 mg/ml) and diprospan as above for three months also. Prior to each injection, the keloids of patients in group 3 were additionally irradiated by a 1,064-nm neodymium-yttrium-aluminum-garnet (Nd:YAG) laser with a single pulse at an energy density of 90-100 J/cm² and a pulse width of 12 msec. Clinical responses were evaluated by patient self-assessment and overall assessment by an observer according to the clinical signs of erythema, pruritus and pliability. A total of sixty-two patients completed the tests of the present study. At 2 and 3 months, the patients in all treatment groups showed an acceptable improvement in nearly all measurements. At the end of the study, the erythema and toughness score was significantly reduced and itch reduction was significantly greater in the diprospan + 5-FU + Nd:YAG group when compared to those in the other groups (P<0.05 for all indexes). The acceptable responses (good to excellent improvements) reported by blinded observers were as follows: 12% in the diprospan group, 48% in the diprospan + 5-FU group and 69% in the diprospan + 5-FU + Nd:YAG group. All of the results indicated that the combination of diprospan + 5-FU + Nd:YAG was the most efficacious therapy for keloid scars.

Evidence-Based Scar Management: How to Improve Results with Technique and Technology

BACKGROUND

Scars represent the visible sequelae of trauma, injury, burn, or surgery. They may induce distress in the patient because of their aesthetically unpleasant appearance, especially if they are excessively raised, depressed, wide, or erythematous. They may also cause the patient symptoms of pain, tightness, and pruritus. Numerous products are marketed for scar prevention or improvement, but their efficacy is unclear.

METHODS

A literature review of high-level studies analyzing methods to prevent or improve hypertrophic scars, keloids, and striae distensae was performed. The evidence from these articles was analyzed to generate recommendations. Each intervention's effectiveness at preventing or reducing scars was rated as none, low, or high, depending on the strength of the evidence for that intervention.

RESULTS

For the prevention of hypertrophic scars, silicone, tension reduction, and wound edge eversion seem to have high efficacy, whereas onion extract, pulsed-dye laser, pressure garments, and scar massage have low efficacy. For the treatment of existing hypertrophic scars, silicone, pulsed-dye laser, CO2 laser, corticosteroids, 5-fluorouracil, bleomycin, and scar massage have high efficacy, whereas onion extract and fat grafting seem to have low efficacy. For keloid scars, effective adjuncts to excision include corticosteroids, mitomycin C, bleomycin, and radiation therapy. No intervention seems to have significant efficacy in the prevention or treatment of striae distensae.

CONCLUSION

Although scars can never be completely eliminated in an adult, this article presents the most commonly used, evidence-based methods to improve the quality and symptoms of hypertrophic scars, as well as keloid scars and striae distensae.

Site-specific gene expression profiling as a novel strategy for unravelling keloid disease pathobiology

Keloid disease (KD) is a fibroproliferative cutaneous tumour characterised by heterogeneity, excess collagen deposition and aggressive local invasion. Lack of a validated animal model and resistance to a multitude of current therapies has resulted in unsatisfactory clinical outcomes of KD management. In order to address KD from a new perspective, we applied for the first time a site-specific in situ microdissection and gene expression profiling approach, through combined laser capture microdissection and transcriptomic array. The aim here was to analyse the utility of this approach compared with established methods of investigation, including whole tissue biopsy and monolayer cell culture techniques. This study was designed to approach KD from a hypothesis-free and compartment-specific angle, using state-of-the-art microdissection and gene expression profiling technology. We sought to characterise expression differences between specific keloid lesional sites and elucidate potential contributions of significantly dysregulated genes to mechanisms underlying keloid pathobiology, thus informing future explorative research into KD. Here, we highlight the advantages of our in situ microdissection strategy in generating expression data with improved sensitivity and accuracy over traditional methods. This methodological approach supports an active role for the epidermis in the pathogenesis of KD through identification of genes and upstream regulators implicated in epithelial-mesenchymal transition, inflammation and immune modulation. We describe dermal expression patterns crucial to collagen deposition that are associated with TGFβ-mediated signalling, which have not previously been examined in KD. Additionally, this study supports the previously proposed presence of a cancer-like stem cell population in KD and explores the possible contribution of gene dysregulation to the resistance of KD to conventional therapy. Through this innovative in situ microdissection gene profiling approach, we provide better-defined gene signatures of distinct KD regions, thereby addressing KD heterogeneity, facilitating differential diagnosis with other cutaneous fibroses via transcriptional fingerprinting, and highlighting key areas for future KD research.

Keloids and Hypertrophic Scars: Pathophysiology, Classification, and Treatment

BACKGROUND

Keloid and hypertrophic scars represent an aberrant response to the wound healing process. These scars are characterized by dysregulated growth with excessive collagen formation, and can be cosmetically and functionally disruptive to patients.

OBJECTIVE

Objectives are to describe the pathophysiology of keloid and hypertrophic scar, and to compare differences with the normal wound healing process. The classification of keloids and hypertrophic scars are then discussed. Finally, various treatment options including prevention, conventional therapies, surgical therapies, and adjuvant therapies are described in detail.

MATERIALS AND METHODS

Literature review was performed identifying relevant publications pertaining to the pathophysiology, classification, and treatment of keloid and hypertrophic scars.

RESULTS

Though the pathophysiology of keloid and hypertrophic scars is not completely known, various cytokines have been implicated, including interleukin (IL)-6, IL-8, and IL-10, as well as various growth factors including transforming growth factor-beta and platelet-derived growth factor. Numerous treatments have been studied for keloid and hypertrophic scars,which include conventional therapies such as occlusive dressings, compression therapy, and steroids; surgical therapies such as excision and cryosurgery; and adjuvant and emerging therapies including radiation therapy, interferon, 5-fluorouracil, imiquimod, tacrolimus, sirolimus, bleomycin, doxorubicin, transforming growth factor-beta, epidermal growth factor, verapamil, retinoic acid, tamoxifen, botulinum toxin A, onion extract, silicone-based camouflage, hydrogel scaffold, and skin tension offloading device.

CONCLUSION

Keloid and hypertrophic scars remain a challenging condition, with potential cosmetic and functional consequences to patients. Several therapies exist which function through different mechanisms. Better understanding into the pathogenesis will allow for development of newer and more targeted therapies in the future.

Botulinum Toxin Off-Label Use in Dermatology: A Review

BACKGROUND

Botulinum toxin is a neurotoxin produced by the bacterium Clostridium botulinum which causes a flaccid muscle paralysis. It is currently used for aesthetic treatments and in the focal hyperhidrosis. Recently, botulinum toxin has also been used experimentally in many other dermatological conditions with good results.

OBJECTIVE

To review and analyze the possible botulinum toxin off-label applications published.

METHODS

A retrospective review of the published data was conducted.

CONCLUSIONS

this potent drug can lead to several off-label indications of interest for dermatologists. Further clinical trials are still needed to better understand the real efficacy and safety of these applications and to standardize injection and dose protocols.

Targeted killing of myofibroblasts by biosurfactant di-rhamnolipid suggests a therapy against scar formation

Pathological myofibroblasts are often involved in skin scarring via generating contractile force and over-expressing collagen fibers, but no compound has been found to inhibit the myofibroblasts without showing severe toxicity to surrounding physiological cells. Here we report that di-rhamnolipid, a biosurfactant secreted by Pseudomonas aeruginosa, showed potent effects on scar therapy via a unique mechanism of targeted killing the myofibroblasts. In cell culture, the fibroblasts-derived myofibroblasts were more sensitive to di-rhamnolipid toxicity than fibroblasts at a concentration-dependent manner, and could be completely inhibited of their specific functions including α-SMA expression and collagen secretion/contraction. The anti-fibrotic function of di-rhamnolipid was further verified in rabbit ear hypertrophic scar models by presenting the significant reduction of scar elevation index, type I collagen fibers and α-SMA expression. In this regard, di-rhamnolipid treatment could be suggested as a therapy against skin scarring.

Novel Insights on Understanding of Keloid Scar: Article Review

Keloid scar, dermal benign fibro-proliferative growth that extends outside the original wound and invades adjacent dermal tissue due to extensive production of extracellular matrix, especially collagen, which caused by over expression of cytokines and growth factors. Although many attempts were made to understand the exact pathophysiology and the molecular abnormalities, the pathogenesis of keloid scar is yet to be determined. Even though there are several treatment options for keloid scars include combination of medical and surgical therapies like combination of surgical removal followed by cryotherapy or intralesional steroid therapy, the reoccurrence rate is still high despite the present treatment. In this review, PubMed, clinical key and Wright State Library web site have been used to investigate any update regarding Keloid disease. We used Keloid, scar formation, hypertrophic scar and collagen as key words. More than 40 articles have been reviewed. This paper reviews literature about keloid scar formation mechanism, the most recent therapeutic options including the ones under research.

Efficacy and safety of triamcinolone acetonide alone and in combination with 5-fluorouracil for treating hypertrophic scars and keloids: a systematic review and meta-analysis

Pathological scars, such as keloids and hypertrophic scars, readily cause physical and psychological problems. Combination 5-fluorouracil (5-FU) with triamcinolone acetonide (TAC) is presumed to enhance the treatment of pathological scars, although supportive evidence is lacking. We aimed to compare the efficacy and safety of TAC alone and in combination with 5-FU for the treatment of hypertrophic scars and keloids. Five databases (PubMed, Medline, Cochrane databases, Embase and CNKI) were searched with the limitations of human subjects and English-language text. Mean differences (MDs), odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. The Cochrane Collaboration's Risk of Bias Tool was used to assess the risk of bias. The control group received intralesional TAC alone, and the experimental group received TAC combined with 5-FU injection. A pooled analysis of the effectiveness based on patient self-assessment after treatment showed that the experimental group achieved better results than the control group (OR = 2·92, 95% CI = 1·63-5·22, P = 0·0003). Similarly, a pooled analysis of the effectiveness based on observer assessment following treatment produced the same conclusion (OR = 4·03, 95% CI = 1·40-11·61, P = 0·010). A meta-analysis of scar height after treatment showed that the experimental group performed better than the control group (MD = -0·14, 95% CI = -0·23-0·05, P = 0·002). The erythema score of the experimental group after treatment was superior (MD = -0·20, 95% CI = -0·34-0·06, P = 0·004). The heterogeneity test showed no heterogeneity among the studies (P > 0·1, I²  = 0%). TAC combined with 5-FU is more suitable for the treatment and prevention of hypertrophic scars and keloids, with greater improvement in scar height and patient satisfaction as well as fewer side effects.

5-Fluorouracil in the Treatment of Keloids and Hypertrophic Scars: A Comprehensive Review of the Literature

Hypertrophic (HTSs) and keloid scars are common dermatological complaints produced by disruption of the normal wound-healing process. Despite a wide array of therapeutic options available to treat these lesions, HTSs and keloids continue to pose a significant challenge to clinicians in everyday practice. The chemotherapeutic drug 5-fluorouracil (5-FU) is a well-known treatment option reserved for recalcitrant HTSs and keloid lesions. We present clinicians with a comprehensive review of the published data concerning the use of 5-FU in the treatment of HTSs and keloids. The current evidence suggests that 5-FU is a safe and practical alternative for the treatment of HTSs and keloids as it may substantially improve the appearance of proliferative scars and reduce the chance of recurrence. This therapeutic option is most effective in conjunction with adjuvant therapy such as corticosteroids. Additional randomized controlled clinical trials with large sample sizes should be conducted to corroborate the existing efficacy and safety data in patients with HTSs and keloids.

The Aldo-Keto Reductase AKR1B10 Is Up-Regulated in Keloid Epidermis, Implicating Retinoic Acid Pathway Dysregulation in the Pathogenesis of Keloid Disease

Keloid disease is a recurrent fibroproliferative cutaneous tumor of unknown pathogenesis for which clinical management remains unsatisfactory. To obtain new insights into hitherto underappreciated aspects of keloid pathobiology, we took a laser capture microdissection-based, whole-genome microarray analysis approach to identify distinct keloid disease-associated gene expression patterns within defined keloid regions. Identification of the aldo-keto reductase enzyme AKR1B10 as highly up-regulated in keloid epidermis suggested that an imbalance of retinoic acid metabolism is likely associated with keloid disease. Here, we show that AKR1B10 transfection into normal human keratinocytes reproduced the abnormal retinoic acid pathway expression pattern we had identified in keloid epidermis. Cotransfection of AKR1B10 with a luciferase reporter plasmid showed reduced retinoic acid response element activity, supporting the hypothesis of retinoic acid synthesis deficiency in keloid epidermis. Paracrine signals released by AKR1B10-overexpressing keratinocytes into conditioned medium resulted in up-regulation of transforming growth factor-β1, transforming growth factor-β2, and collagens I and III in both keloid and normal skin fibroblasts, mimicking the typical profibrotic keloid profile. Our study results suggest that insufficient retinoic acid synthesis by keloid epidermal keratinocytes may contribute to the pathogenesis of keloid disease. We refocus attention on the role of injured epithelium in keloid disease and identify AKR1B10 as a potential new target in future management of keloid disease.