Experience with difficult keloids

Metformin Inhibits Epithelial-to-Mesenchymal Transition of Keloid Fibroblasts via the HIF-1α/PKM2 Signaling Pathway

Background: Epithelial-to-mesenchymal transition (EMT) is a process whereby epithelial cells lose cell-cell contacts and acquire expression of mesenchymal components and manifest a migratory phenotype. Recent studies indicated that EMT is involved in the development of keloids. Therefore, this study aims to investigate the mechanisms of the effects of metformin in hypoxia-induced EMT in keloid fibroblasts (KFs). Methods: KFs were cultured in a hypoxia incubator to induce EMT and were treated with or without metformin. Cell viability was evaluated by a cell counting kit 8 (CCK-8), and cell migration was measured by the transwell assay. The expression levels of HIF-1α, E-cadherin, vimentin, phosphorylated p70s6k (p-p70s6k) and pyruvate kinase M2 (PKM2) were evaluated by western blotting. Results: Hypoxia promoted EMT in KFs. Metformin significantly inhibited the expression of HIF-1α and partially abolished hypoxia-induced EMT. PKM2 is involved in hypoxia-induced EMT of KFs and metformin decreased the expression of p-p70s6k and PKM2. Conclusions: Metformin abolishes hypoxia-induced EMT in KFs by inhibiting the HIF-1α/PKM2 signaling pathway. Our study provides a novel mechanistic insight into potential use of metformin for treatment of keloids.

Hyperbaric oxygen therapy can ameliorate the EMT phenomenon in keloid tissue

BACKGROUND

Hyperbaric oxygen therapy (HBOT) has been widely used in the clinical setting. In this study, HBOT therapy was evaluated for its ability to ameliorate the epithelial-to-mesenchymal transition (EMT) phenomenon in keloid tissue.

METHODS

Keloid patients were randomly divided into two groups: keloid patients (K group, 9 patients) and keloid patients receiving HBOT (O group, 9 patients). A third group with normal skin (S group, 9 patients) was established for control. Before HBOT and surgery, a laser Doppler flowmeter was used to measure the keloid blood supply of patients in the O group. Hematoxylin and eosin (H&E) staining was used to observe morphology. E-cadherin, ZO-1, vimentin, fibronectin, vascular endothelial growth factor (VEGF), and hypoxia inducible factor (HIF)-1α were measured by immunofluorescence staining and Western blot analysis. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to evaluate the mRNA expression level of these factors as well.

RESULTS

In the O group, keloid blood perfusion was significantly reduced after patients received HBOT. Compared with the K group, lower expression levels of vimentin, vibronectin, VEGF, and HIF-1α were observed in the O group, whereas the expression of E-cadherin and ZO-1 was significantly higher. The mRNA expression of E-cadherin and ZO-1 was also increased after HBOT.

CONCLUSIONS

The expression levels of factors related to the EMT phenomenon were significantly reversed in keloid patients after they received HBOT, indicating that HBOT may be an effective therapy against the EMT phenomenon in keloid patients.

The Efficacy of Triamcinolone Acetonide in Keloid Treatment: A Systematic Review and Meta-analysis

Keloid is a cutaneous dermal outgrowth resulting from uncontrolled deposition of collagen and glycosaminoglycan around the wound. The uncontrolled and persistent growth of keloids scar will result in cosmetic disfigurement, functional impairment, and affect the quality of life. Triamcinolone acetonide (TAC) is traditionally employed in treating keloid scars. In this study, we aim to evaluate the effectiveness of TAC and compare it with other common therapy employed in keloid treatment. Only randomized controlled trial (RCT) and controlled trial were included. Inverse variance risk ratio, weighted mean difference, and corresponding 95% confidence intervals were calculated to evaluate the effect of intervention. Meta-analysis indicated that TAC treatment significantly reduced the size of keloid compared to untreated control. Reduction in size was statistically different in favor of TAC compared to silicone gel sheet. Significant difference in favor of TAC was observed compared with verapamil in term of vascularity and scar pliability. TAC treatment was more effective in reducing scar thickness in comparison with cryotherapy. However, the current meta-analysis has several limitations. Only a limited number of trials with the same comparison are available. Most trials recruited a small number of patients and used inconsistent outcome assessment. Most trials did not provide detail information on allocation concealment and blinding. Therefore, further evaluation in multi-center RCTs with consistent comparisons and outcome measurements are warrant to reach a consensus on the selection between TAC and different treatment modalities.

Chemokine-Like Factor 1 (CKLF-1) is Overexpressed in Keloid Patients: A Potential Indicating Factor for Keloid-Predisposed Individuals

Chemokine-like factor 1 (CKLF-1) is a novel cytokine which have a crucial role in immune and inflammatory responses. In this study, the expression level of CKLF-1 was measured to assess the difference between keloid patients and people without keloid. Fifty samples were taken from 30 patients: 10 keloid patients; 10 scar patients; and 10 patients without obvious scarring. Patients were randomly selected from the hospitalized patients of Peking Union Medical College Hospital from September 2013 to July 2015. Five groups of samples were established: keloid samples from keloid patients (K); normal skin samples from keloid patients (KS); scar samples from scar patients (C); normal skin samples from scar patients (CS); and normal skin samples from patients without obvious scarring (S). Hematoxylin and eosin (H&E) staining was used to observe morphological changes. CKLF-1, IL-6, IL-8, IL-18, and TGF-β were detected by immunohistochemical and western blot technology. The expression of CKLF-1's mRNA was also measured by the real-time quantitative polymerase chain reaction (RT-qPCR). Compared to the K group, the other 4 groups presented significantly less inflammatory infiltration and lower expression levels of CKLF-1, IL-6, IL-8, IL-18, and TGF-β. Among the 3 normal skin groups, the expression level of CKLF-1 was significantly higher in the KS group than in the CS or S group. The mRNA expression was also obvious in the K and KS groups. CKLF-1 and other inflammatory factors were overexpressed in the samples from keloid patients, indicating that the formation of keloid may be related to inflammation and that CKLF-1 may play an important role in this process.

New insights on keloids, hypertrophic scars, and striae

This article presents an overview of the literature regarding treatments for keloid disease, hypertrophic scars, and striae distensae in dark pigmented skin. Striae, keloid, and hypertrophic scarring present a challenging problem for both the clinician and patient. No single therapy is advocated for hypertrophic scars, keloid scars, or striae distensae. New therapies have shown promise in the treatment of hypertrophic and keloid scars, and in patients with dark pigmented skin. This article provides guidance on the assessment and determination of patients' suitability for certain treatment options, as well as advice on the follow-up of patients affected with problematic scarring and striae.

Levels of evidence for the treatment of keloid disease

INTRODUCTION

Keloid disease presents a significant burden for patients and a significant therapeutic challenge for clinicians. Multiple treatments have been proposed, but with the increasing drive towards effective use of resources, therapeutic options need to be evaluated in terms of the levels of evidence supporting their use.

AIM

To retrieve and review the primary clinical studies evaluating keloid disease therapy over the last 25 years and assign levels of evidence for the treatment modalities evaluated.

METHOD

A Medline search was conducted to identify all primary clinical studies evaluating the treatment of keloid disease, published in English since 1980 (excluding single case reports). Studies were assigned a level of evidence (LOE-1, highest quality to LOE-5, lowest) adapted from the Oxford Centre for Evidence-based Medicine.

RESULTS

13 (12%) of 112 studies retrieved were assigned LOE-2, 99 (88%) assigned LOE-4. There were no LOE-1 studies. Ten of the LOE-2 studies evaluated silicone-based therapy or laser therapy. Most studies evaluating steroids, cryosurgery, laser therapy and post-surgical adjuvant therapy provide level 4 evidence.

CONCLUSION

High quality research in evaluating keloid therapy is lacking. There is a definite need for well designed and properly reported randomised controlled trials, to provide clinicians with a sound body of evidence on which to inform decision making.

Abnormal wound healing: keloids

Wound healing is a complex and carefully regulated physiologic response to a traumatic injury. Deregulation of this coordinated process can lead to exuberant scar formation as seen in keloids and hypertrophic scars. Despite their common occurrence, keloids remain one of the most challenging dermatologic conditions to successfully treat and may have significant psychosocial impact for the patient. In this review, we discuss the clinical features, genetics, epidemiology, and treatment of keloids.

Bleomycin tattooing as a promising therapeutic modality in large keloids and hypertrophic scars

BACKGROUND

Cryotherapy combined with intralesional triamcinolon injection is the most common traditional therapy for hypertrophic scars and keloids. The literature contains few articles on the use of bleomycin tattoo for treatment of these conditions.

OBJECTIVE

This study compares the efficacy of bleomycin tattoo with that of cryotherapy combined with intralesional triamcinolon injection for the treatment of keloids and hypertrophic scars.

MATERIALS AND METHODS

Forty-five patients with hypertrophic scars or keloids were randomly divided into two groups. Group A was treated with bleomycin tattoo, and group B, with cryotherapy combined with intralesional triamcinolon injection. There were four therapeutic sessions at 1-month intervals. All patients were followed for 3 months after the end of treatment.

RESULTS

Therapeutic response in lesions less than 100 mm2 was higher than 88% in both groups, but in larger lesions, the therapeutic response to bleomycin was significantly better than cryotherapy combined with intralesional triamcinolon injection (p = .03). In group A, no relationship was observed between therapeutic response and lesion size (p = .58); however, in group B smaller lesions (< 100 mm2) displayed better therapeutic response (p = .007).

CONCLUSIONS

Bleomycin tattoo may be more effective than cryotherapy combined with intralesional triamcinolon injection in treatment of larger keloids and hypertrophic scars (size > 100 mm2).

Hypertrophic scars and keloids: etiology and management

Keloid and hypertrophic scars have affected patients and frustrated physicians for centuries. Keloid and hypertrophic scars result from excessive collagen deposition, the cause of which remains elusive. Clinically, these scars can be disfiguring functionally, aesthetically, or both. A thorough understanding of the pathophysiology and clinical nature of the scar can help define the most appropriate treatment strategy. Although many articles have been published on the management of hypertrophic and keloid scars, there is no universally accepted treatment protocol. Prevention of keloid and hypertrophic scars remains the best strategy; therefore, those patients with a predisposition to develop excessive scar formation should avoid nonessential surgery. Once a scar is present, there are many treatments from which to choose. Hypertrophic scars and keloids have been shown to respond to radiation, pressure therapy, cryotherapy, intralesional injections of corticosteroid, interferon and fluorouracil, topical silicone or other dressings, and pulsed-dye laser treatment. Simple surgical excision is usually followed by recurrence unless adjunct therapies are employed. Biologic agents that are directed towards the aberrant collagen proliferation that characterizes keloid and hypertrophic scars might be an important addition to the current armamentarium of modalities in the near future.