[Keloid of the earlobe after ear piercing. Not only a surgical problem]

The PI3K-Akt-mTOR and Associated Signaling Pathways as Molecular Drivers of Immune-Mediated Inflammatory Skin Diseases: Update on Therapeutic Strategy Using Natural and Synthetic Compounds

The dysregulated phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway has been implicated in various immune-mediated inflammatory and hyperproliferative dermatoses such as acne, atopic dermatitis, alopecia, psoriasis, wounds, and vitiligo, and is associated with poor treatment outcomes. Improved comprehension of the consequences of the dysregulated PI3K/Akt/mTOR pathway in patients with inflammatory dermatoses has resulted in the development of novel therapeutic approaches. Nonetheless, more studies are necessary to validate the regulatory role of this pathway and to create more effective preventive and treatment methods for a wide range of inflammatory skin diseases. Several studies have revealed that certain natural products and synthetic compounds can obstruct the expression/activity of PI3K/Akt/mTOR, underscoring their potential in managing common and persistent skin inflammatory disorders. This review summarizes recent advances in understanding the role of the activated PI3K/Akt/mTOR pathway and associated components in immune-mediated inflammatory dermatoses and discusses the potential of bioactive natural products, synthetic scaffolds, and biologic agents in their prevention and treatment. However, further research is necessary to validate the regulatory role of this pathway and develop more effective therapies for inflammatory skin disorders.

Increased c-Met phosphorylation is related to keloid pathogenesis: implications for the biological behaviour of keloid fibroblasts

Keloid is induced by a pathological wound healing response, and hepatocyte growth factor (HGF) is known to be involved in tissue repair via the activation of its primary receptor, c-Met. We aimed to investigate whether c-Met activation is implicated in keloid pathogenesis. HGF, c-Met, phosphorylated c-Met (p-Met), Ki-67, collagen I protein, and MET gene expression were detected in five normal skin and 30 keloid tissues by immunohistochemistry and quantitative real-time polymerase chain reaction analysis, respectively. The influence of p-Met expression on the biological behaviour of keloid fibroblasts was further investigated with regard to cell proliferation, motility, invasiveness, collagen I expression, and intracellular signaling in vitro. p-Met protein and MET gene expression but not HGF or c-Met protein expression showed significant increases in keloid tissues than dermal layer of normal skin tissues. In keloid tissues, p-Met expression was significantly associated with keloid size, Ki-67 and collagen I expression. Moreover, p-Met expression was also related to proliferation, migration, invasiveness, collagen I expression and activation of AKT and Erk in keloid fibroblasts in vitro. c-Met activation may have a strong influence on keloid pathogenesis, and it can be investigated further as a potential molecular target for keloid therapy.

RUNX3 expression is associated with sensitivity to pheophorbide a-based photodynamic therapy in keloids

Runt-related transcription factor 3 (RUNX3) has recently been reported to be a possible predictor of sensitivity of cancer cells for photodynamic therapy (PDT), a promising therapeutic modality for keloids. In this study, we aimed to elucidate the implications of RUNX3 for keloid pathogenesis and sensitivity to pheophorbide a-based PDT (Pa-PDT). RUNX3 and proliferating cell nuclear antigen (PCNA) expression were examined in 6 normal skin samples and 32 keloid tissue samples by immunohistochemistry. We found that RUNX3 expression was detected more often in keloid tissues than in dermis of normal skin. In keloid tissues, RUNX3 expression was significantly increased in patients presenting with symptoms of pain or pruritus, and was also significantly related to PCNA expression. The therapeutic effect of Pa-PDT was comparatively investigated in keloid fibroblasts (KFs) with and without RUNX3 expression. Significant differences were found after Pa-PDT between KFs with and without RUNX3 expression in cell viability, proliferative ability, type I collagen expression, generation of reactive oxygen species (ROS), and apoptotic cell death. In addition, RUNX3 expression was significantly decreased after Pa-PDT in KFs, and KFs with downregulation of RUNX3 showed significantly increased cell viability after Pa-PDT. Pa-PDT may be a potential therapeutic modality for keloids, and RUNX3, as a possible contributor to keloid pathogenesis, may improve sensitivity to Pa-PDT in KFs.

Potent dual inhibitors of TORC1 and TORC2 complexes (KU-0063794 and KU-0068650) demonstrate in vitro and ex vivo anti-keloid scar activity

Mammalian target of rapamycin (mTOR) is essential in controlling several cellular functions. This pathway is dysregulated in keloid disease (KD). KD is a common fibroproliferative dermal lesion with an ill-defined treatment strategy. KD demonstrates excessive matrix deposition, angiogenesis, and inflammatory cell infiltration. In KD, both total and phosphorylated forms of mTOR and p70^S6K(Thr421/Ser424) are upregulated. Therefore, the aim of this study was to investigate adenosine triphosphate–competitive inhibitors of mTOR kinase previously unreported in keloid and their comparative efficacy with Rapamycin. Here, we present two mTOR kinase inhibitors, KU-0063794 and KU-0068650, that target both mTORC1 and mTORC2 signaling. Treatment with either KU-0063794 or KU-0068650 resulted in complete suppression of Akt, mTORC1, and mTORC2, and inhibition of keloid cell spreading, proliferation, migration, and invasive properties at a very low concentration (2.5 μmol l⁻¹). Both KU-0063794 and KU-0068650 significantly (P<0.05) inhibited cell cycle regulation and HIF1-α expression compared with that achieved with Rapamycin alone. In addition, both compounds induced shrinkage and growth arrest in KD, associated with the inhibition of angiogenesis, induction of apoptosis, and reduction in keloid phenotype–associated markers. In contrast, Rapamycin induced minimal antitumor activity. In conclusion, potent dual mTORC1 and mTORC2 inhibitors display therapeutic potential for the treatment of KD.

Keloid disease can be inhibited by antagonizing excessive mTOR signaling with a novel dual TORC1/2 inhibitor

Keloid disease (KD) is a fibroproliferative lesion of unknown etiopathogenesis that possibly targets the PI3K/Akt/mTOR pathway. We investigated whether PI3K/Akt/mTOR inhibitor, Palomid 529 (P529), which targets both mammalian target of rapamycin complex 1 (mTORC-1) and mTORC-2 signaling, could exert anti-KD effects in a novel KD organ culture assay and in keloid fibroblasts (KF). Treatment of KF with P529 significantly (P < 0.05) inhibited cell spreading, attachment, proliferation, migration, and invasive properties at a low concentration (5 ng/mL) and induced substantial KF apoptosis when compared with normal dermal fibroblasts. P529 also inhibited hypoxia-inducible factor-1α expression and completely suppressed Akt, GSK3β, mTOR, eukaryotic initiation factor 4E-binding protein 1, and S6 phosphorylation. P529 significantly (P < 0.05) inhibited proliferating cell nuclear antigen and cyclin D and caused considerable apoptosis. Compared with rapamycin and wortmannin, P529 also significantly (P < 0.05) reduced keloid-associated phenotypic markers in KF. P529 caused tissue shrinkage, growth arrest, and apoptosis in keloid organ cultures and substantially inhibited angiogenesis. pS6, pAkt-Ser473, and mTOR phosphorylation were also suppressed in situ. P529 reduced cellularity and expression of collagen, fibronectin, and α-smooth muscle actin (substantially more than rapamycin). These pre-clinical in vitro and ex vivo observations are evidence that the mTOR pathway is a promising target for future KD therapy and that the dual PI3K/Akt/mTOR inhibitor P529 deserves systematic exploration as a candidate agent for the future treatment of KD.

Promising Results from a Pilot Study on Compression Treatment of Ear Keloids

Background:

Ear keloids continue to be a therapeutic challenge.

Objective:

To evaluate the clinical success of a modified “oyster splint technique.”

Methods:

Ten patients with an ear keloid agreed to receive the compression therapy. After surgical removal, a compressive device made of acrylic resin was applied on top of a silicone gel sheet and patients were asked to wear the splint 23 hours a day for at least 8 months. If the scar showed a tendency to grow, corticosteroids were injected intralesionally. In addition to recurrence rate, other parameters and wearing times were obtained by an interview.

Results:

Two of 10 patients experienced a recurrence in a mean follow-up period of 18.2 months (range 4–44 months). The daily wearing time of the compression splint was critical for the success of the treatment ( p = .022). The splint had to be worn at least 10 hours a day for a minimum of 8 months to prevent recurrence. However, the need for additional intralesional steroid injections was significantly lower in patients wearing the splint for more than 20 hours per day ( p = .048). The splint treatment was painless for 80% of patients. The therapeutic result was given a median mark of 1.75 (1 = best, 6 = worst).

Conclusion:

Although it requires considerable time and effort, the technique seems to be a promising therapy.

Therapy of auricular keloids: review of different treatment modalities and proposal for a therapeutic algorithm

Keloids are abnormal wound reactions of connective tissue. Auricular keloids can develop as a result of, e.g., otoplasty, ear piercing, or skin trauma. A wide variety of therapeutic options exists, including surgery as primary treatment. Furthermore, there are medical, physical, radiotherapeutic and experimental options. The present paper focuses on the different techniques including the therapeutic outcome and quality rating for each chosen pathway. In addition to the experience of the university hospitals, a thorough review of the literature was performed in order to update and compare today's therapeutic options. Surgical techniques are customized to the lesion's specific localization and extent. They may include revision of otoplasty. With medical treatment, established modalities such as steroid injection have to be distinguished from experimental methods like interferon, 5-FU, verapamil, imiquimod, or mitomycin C. Radiation is generally accepted to be effective, especially applied accompanying surgery, but needs to be restricted due to possible side effects. Physical therapy, e.g., pressure in a variety of application modalities, has gained a profound position in the therapy of auricular keloids. The success rates of the different treatment modalities vary markedly, and the number of patients per study is considerably low. Resuming the results, a periodic follow-up and good patients' compliance are mandatory to early realize and treat auricular keloids. However, studies are needed to evaluate accepted and experimental therapies including larger number of patients.

Cryosurgery in the Treatment of Earlobe Keloids: Report of Seven Cases

BACKGROUND

Keloids are benign cutaneous lesions that result from excessive collagen synthesis and deposition. Earlobe keloids in particular are seen as a complication of plastic surgery or piercing. Many different treatment modalities have been used, often with unsatisfactory results.

METHODS

We have made a retrospective analysis of seven young patients (ages 9 to 22 years) with earlobe keloids. Scarring followed plastic surgery in six cases and piercing in one case. All patients were treated with cryosurgery as the monotherapy. The freeze time and the number of sessions varied depending on the clinical findings, the effect of the treatment, and the patients' tolerance. Cryotherapy was started 6 to 24 months after keloid development.

RESULTS

Scar volume was reduced in all cases. Complete flattening in five patients and a pronounced reduction to a maximum of 25% of the previous thickness in one other patient were achieved. One patient discontinued the therapy because of soreness after only partial improvement. The procedure was painful for all patients; no further side effects were noticed. No recurrence was observed within 1 to 4.5 years of follow-up.

CONCLUSION

We present an excellent effect of cryosurgery as the monotherapy for the treatment of earlobe keloid scars of young patients.