Facial Plastic Surgery Controversies: Keloids

The m6A-methylated mRNA pattern and the activation of the Wnt signaling pathway under the hyper-m6A-modifying condition in the keloid

Purpose: The present study was carried out to investigate the global m⁶A-modified RNA pattern and possible mechanisms underlying the pathogenesis of keloid. Method: In total, 14 normal skin and 14 keloid tissue samples were first collected on clinics. Then, three samples from each group were randomly selected to be verified with the Western blotting to determine the level of methyltransferase and demethylase. The total RNA of all samples in each group was isolated and subjected to the analysis of MeRIP sequencing and RNA sequencing. Using software of MeTDiff and htseq-count, the m⁶A peaks and differentially expressed genes (DEGs) were determined within the fold change >2 and p-value < 0.05. The top 10 pathways of m⁶A-modified genes in each group and the differentially expressed genes were enriched by the Kyoto Encyclopedia of Genes and Genomes signaling pathways. Finally, the closely associated pathway was determined using the Western blotting and immunofluorescence staining. Results: There was a higher protein level of WTAP and Mettl3 in the keloid than in the normal tissue. In the keloid samples, 21,020 unique m⁶A peaks with 6,573 unique m⁶A-associated genetic transcripts appeared. In the normal tissue, 4,028 unique m⁶A peaks with 779 m⁶A-associated modified genes appeared. In the RNA sequencing, there were 847 genes significantly changed between these groups, transcriptionally. The genes with m⁶A-methylated modification and the upregulated differentially expressed genes between two tissues were both mainly related to the Wnt signaling pathway. Moreover, the hyper-m⁶A-modified Wnt/β-catenin pathway in keloid was verified with Western blotting. From the immunofluorescence staining results, we found that the accumulated fibroblasts were under a hyper-m⁶A condition in the keloid, and the Wnt/β-Catenin signaling pathway was mainly activated in the fibroblasts. Conclusion: The fibroblasts in the keloid were under a cellular hyper-m⁶A-methylated condition, and the hyper-m⁶A-modified highly expressed Wnt/β-catenin pathway in the dermal fibroblasts might promote the pathogenesis of keloid.

Challenges in the Management of Upper Lid Keloid

A middle-aged lady presented with a firm, nontender mass on the left upper lid and area behind the left ear following lid reconstruction with postauricular graft for cicatricial ectropion 11 months prior. She had a similar mass on the right shin. She was diagnosed as a case of multiple keloids. Intralesional injection of triamcinolone acetonide suspension and 5-Fluorouracil (5-FU) in the upper lid keloid resulted in ulceration of its surface. Surgical excision, injection of 5-FU in the keloid bed with temporal forehead flap reconstruction, was performed. Occurrence of inadvertent postoperative wound infection with Acinetobacter baumannii was treated with local dressing with colistimethate sodium. Adjuvant therapy with topical imiquimod cream 5% was given subsequently for 24 weeks with no recurrence of the lid keloid after 16 months. The patient was managed using a combination of conservative and surgical therapy and multidisciplinary team work and kept on a long term follow-up.

Adjuvant Radiotherapy for Keloids

Radiotherapy is one of the therapeutic methods for keloids, and the irradiation technique has innovated from superficial X-ray to brachytherapy after decades of clinical practice. At present, the application of adjuvant radiotherapy has been widely accepted by clinicians, while the consensus of optimal adjuvant radiotherapy strategies for keloids has not been reached. Factors such as radiation timing, dose, fractions, and lesion locations may be associated with the clinical outcomes of patients with keloids after radiotherapy while a comprehensive review is lacking. Herein, this review summarized the published literature of adjuvant radiotherapy for keloids involving mechanism, timing, dose, fractions, and complications, etc., which may facilitate clinical decision making.Level of Evidence III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

PAX5 activates telomerase activity and proliferation in keloid fibroblasts by transcriptional regulation of SND1, thus promoting keloid growth in burn-injured skin

OBJECTIVE

Staphylococcal nuclease domain-containing 1 (SND1) that functioned as an oncogene in a variety of tumors was upregulated in burn-injured skin tissues, and this study aims to investigate the effect of SND1 on keloid and elucidate the underlying mechanism.

METHODS

Keloid fibroblasts (KFs) and normal skin fibroblasts (NFs) were isolated from the keloid tissues and adjacent normal skin tissues of keloid patients. The SND1 expression was assessed in keloid tissues and KFs with Western blot assay. Gain- and loss-of-function experiments were performed to investigate the role of SND1 in proliferation, colony formation, telomerase activity, expression of fibrogenic genes and production of pro-inflammatory factors in KFs. Chromatin immunoprecipitation (CHIP) and Dual-luciferase reporter gene assays were used to verify the interaction of Paired-box gene 5 (PAX5) on SND1 promoter. Then, a series of rescue experiments were performed to verify the effects of SND1 overexpression on PAX5 knockdown-mediated KF functions. Finally, the role of SND1 in keloid formation in vivo was validated in mice with keloid implantation.

RESULTS

SND1 was upregulated in keloid tissues and KFs. SND1 positively regulated proliferation, colony formation, telomerase activity, production of pro-inflammatory factors and expression of fibrogenic genes. PAX5 directly bound to the SND1 promoter to transcriptionally regulate SND1 expression and positively regulated SND1-mediated KF functions via the ERK/JNK pathway. In vivo assay further demonstrated that SND1 displayed a positive effect on keloid formation.

CONCLUSION

SND1 transcriptionally regulated by PAX5 promotes keloid formation through activating telomerase activity via the ERK/JNK signaling pathways, which provides a promising therapeutic target for clinical treatment of burned skin keloid.

Long non-coding RNA CACNA1G-AS1 promotes proliferation and invasion and inhibits apoptosis by regulating expression of miR-205 in human keloid fibroblasts

Background: Keloid is a fibrous tissue proliferative disease in which proliferative scars grow beyond the boundary of the original wound skin. Long non-coding RNAs (lncRNAs), as competing endogenous RNAs (ceRNAs), bind to microRNAs (miRNAs) to regulate various biological processes. The present study was aim to illuminate the mechanism of calcium voltage-gated channel subunit alpha1 G antisense RNA 1 (CACNA1G-AS1) in human keloid fibroblasts. Methods: CACNA1G-AS1 and miR-205 levels were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8) assay was used to measure the proliferation and transwell assay was performed to evaluate cell invasion. Furthermore, the apoptosis rates of cells were evaluated by flow cytometry analysis, and the activity of caspase-3 in keloid fibroblasts was tested by Caspase-3 activity assay. Dual luciferase reporter assay was carried out to examine the relationship between CACNA1G-AS1 and miR-205 and RNA immunoprecipitation (RIP) assay was conducted to further confirm the relation. Results: CACNA1G-AS1 level was up-regulated in keloid tissues and keloid fibroblasts. CACNA1G-AS1 overexpression promoted proliferation and invasion and suppressed apoptosis of keloid fibroblasts. Moreover, miR-205 was targeted by CACNA1G-AS1 and miR-205 was markedly decreased in keloid tissues and keloid fibroblasts. Also, miR-205 expression was negatively regulated by CACNA1G-AS1 and miR-205 silencing enhanced proliferation and invasion and inhibited apoptosis. Furthermore, CACNA1G-AS1 and miR-205 played the antagonistic role in miR-205 expression, proliferation, invasion, and apoptosis of keloid fibroblasts. Conclusion: CACNA1G-AS1 suppressed miR-205 expression to promote proliferation and invasion and inhibit apoptosis in human keloid fibroblasts.

Influence of pharmacological preconditioning on the results of lifting operations efficiency

The main aim of the study is to determine the effectiveness and safety of lifting operations in women with varying degrees of involuntary changes of facial skin, in particular when applying pharmacological conditioning, with the objectification of the role of the latter.

Materials and methods

A research and surgical treatment were conducted to eliminate involutional changes of various degrees in the facial skin of 461 women aged 35–75 years. Surface lifting was performed in 20.2% of patients, SMAS-lifting – 49.0%, SMAS-lifting with a three-level endoscopic assist lift of the lower face zone was performed in 30.8% of women. Before the surgery in 13.2% of cases, I degree of involutional changes in facial skin was registered, 47.9% – grade II, 38.9% – grade III. Patients were divided into two comparable groups. With the standard preparation without additional drug correction, 299 women (64.9%) were operated on in the preoperative period, they made up a comparison group. The main group included 162 (35.1%) women who underwent therapeutic conditioning before the lifting operation (Cytoflavin, n = 86; Actovegin n = 23; Ethylmethylhydroxypyridine succinate, n = 32; Meldonium, n = 21; Pentoxifylline, n = 31; Vinpocetine n = 27). Instrumental evaluation of the skin dermal microcirculation was performed using laser Doppler flowmetry and estimation of transcutaneous oxygen tension. In the blood plasma, the parameters of free radical processes (FRP) were studied. FRP were studied in terms of generation of active oxygen forms by leukocytes – intensity of chemiluminescence basal and intensity of chemiluminescence stimulated, as well as antiperoxide plasma activity and malondialdehyde. Early postoperative complications were analyzed, the number of repeated lifting surgical corrections on the face was studied for 5 years.

Results

The role of FRP in the pathogenesis of involuntary changes in the facial skin has been established. The imbalance of FRP was expressed in the intensification of the reactive oxygen species generation and products of lipid peroxidation. This correlated with disorders of cutaneous microcirculation and a decrease in the saturation of the facial tissues with oxygen, manifested by an increasing energy deficit and the severity of involutional skin changes. The obtained data justify the expediency of using pharmacological conditioning with energy correcting antioxidant medicine. Preoperative conditioning allowed to reduce the number of early postlifting complications associated with tissue trophism in a quarter, especially during surface lifting. In addition, in the preconditioning group, the scar was more cosmetic already at the seventh day after the operation. Based on the study of postoperative catamnesis, self-assessment data and laboratory-instrumental methods of skin system examination in people of different ages, it was revealed that while using SMAS-lifting with a three-level endoscopic-assisted lifting of the lower part of the face, the lowest frequency of complications and the best 5-year effectiveness were established.