Decoding the molecular landscape of keloids: new insights from single-cell transcriptomics.

Keloids are a fibrotic disease caused by an excessive accumulation of extracellular matrix in the dermis; they have neoplasia-like properties of aggressive growth and high posttreatment recurrence rates. Therefore, it is imperative to gain additional insight into the pathobiology of keloid formation. Single-cell RNA sequencing (scRNA-seq) technology has brought data-driven innovation to understanding the pathogenesis of keloids by breaking the limitations of traditional sequencing technologies to resolve cell composition and to distinguish functional cell subtypes at an unprecedented resolution. The present review aims to cover the application of scRNA-seq technology in keloids and its exploratory findings, including the depiction of the cellular landscape of keloids, fibroblast heterogeneity, the lineage development of Schwann cells and the mesenchymal-activation phenomenon of endothelial cells. Furthermore, scRNA-seq records the transcriptional profiles of fibroblasts and immune cells in a more refined manner, and this gene expression information provides excellent material for inferring intercellular communication networks and lays an important theoretical foundation for future studies.

Multi-omics integrative analysis reveals the role of tumor necrosis factor superfamily member 4 in keloidal scarring.

OBJECTIVES: To identify aberrantly expressed immune molecules in keloids and to explore their possible biologic significance. METHODS: Immune molecules with abnormal expression were identified based on immune gene sequencing of keloids, microarray datasets and high-throughput sequencing datasets and methylation microarray datasets from the Gene Expression Omnibus (GEO) database, and real-time quantitative PCR analysis. RESULTS: Upregulation of tumor necrosis factor superfamily member 4 (TNFSF4) in keloids was identified. Enrichment analysis found that high TNFSF4 expression was associated with immune processes, such as regulation of neutrophil chemotaxis, dendritic cell chemotaxis, and antigen processing and presentation. Single-cell RNA sequencing (scRNA) results suggested that TNFSF4 was upregulated in mesenchymal fibroblasts, which are the critical cells in skin fibrosis. This high expression of TNFSF4 enhanced cell-to-cell interactions in fibrosis-related pathways, including the fibronectin 1 (FN1) and collagen pathways. Mesenchymal fibroblasts expressing TNFSF4 significantly upregulated gene expression in extracellular matrix organization and wound healing processes. CONCLUSIONS: Our study revealed upregulation of the immune molecule TNFSF4 in keloids at the multi-omics level and its effects on intercellular crosstalk and transcriptional profiles of mesenchymal fibroblasts. Investigation of TNFSF4 as an immune checkpoint molecule may represent a new direction for keloid treatment research.

Risk factors associated with keloid infections: A five-year retrospective study.

Keloid infections reduce patient-reported quality of life greatly. Characteristics and risk factors of keloid infections have not been thoroughly studied. So, a retrospective cohort study was conducted focusing on the potential risk factors, microbiologic cultures and histological findings. Keloid patients consulting for surgical interventions were included in this study. Data were collected from their electronic medical records. 564 patients were recruited with the keloid infection rate being 22.4%. For adult patients, age above 40 years (OR, 2.84; P = .000), disease duration of 12 years or more (OR, 3.03; P = .000), the number of keloids over 3 (OR, 1.59; P = .050) and the presence of family history (OR, 1.91; P = .027) were significantly associated with keloid infections. Suppurative keloids were located mostly in thorax (61.79%). For the under-age subgroup(n = 25), family history was frequently seen in patients with infections. Microbiologic cultures revealed a mixed spectrum of bacteria including Staphylococcus (25%), Actinomyces (30%) and Prevotella (10%). The rate of epidermoid cysts was 19.7% in histological examination. Age > 40 years, disease duration ≥12 years, the number of keloids >3 and the presence of family history are risk factors for keloid infections.

A Nomogram with the Keloid Activity Assessment Scale for Predicting the Recurrence of Chest Keloid after Surgery and Radiotherapy.

BACKGROUND: Patients with chest keloids undergoing surgery and adjuvant radiotherapy still have a high recurrence rate, which is a critical problem. The level of keloid activity has not been studied, and a nomogram model for predicting keloid recurrence has not been established in previous studies. METHODS: A total of 145 patients with chest keloids who underwent surgery and radiotherapy between January 2015 and January 2019 at Peking Union Medical College Hospital were included in our study. Demographic and clinical features and the score of KAAS were analyzed. We compared the area under the curve (AUC) and decision curve analysis (DCA) between KAAS and the Vancouver scar scale (VSS) and established a nomogram model for predicting the risk of recurrence. We used bootstrap and calibration plots to evaluate the performance of the nomogram. RESULTS: The KAAS can predict recurrence in patients with chest keloids after surgery and radiotherapy. Areas under the curve (AUCs) of KAAS and VSS were 0.858 and 0.711, respectively (p < 0.001). Decision curve analysis (DCA) demonstrated that the KAAS was better than the VSS. Complications after treatment may be risk factors for keloid recurrence. We created a nomogram by using complications and KAAS. The AUC was 0.871 (95% CI 0.812-0.930). The ROC of the model's bootstrap was 0.865 and was well calibrated. CONCLUSIONS: The KAAS can be used to predict the recurrence and we developed a nomogram for predicting the recurrence of chest keloids after surgery and adjuvant radiotherapy. LEVEL OF EVIDENCE IV: 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 .

Single-cell RNA sequencing reveals distinct immunology profiles in human keloid.

Keloids, characterized by skin fibrosis and excessive accumulation of extracellular matrix, remain a therapeutic challenge. In this study, we systematically capture the cellular composition of keloids by the single-cell RNA sequencing technique. Our results indicated that there are significant differences in most cell types present between 12 pairs of keloid and adjacent normal tissue. We found that fibroblasts, endothelial cells, mast cells, mural cells, and Schwann cells increased significantly in keloid. The proportion of mesenchymal fibroblast subpopulations in keloids was markedly higher than those in the surrounding normal skin tissue. Furthermore, we found that the immune profiles between two groups varied significantly. The proportion of macrophages in the keloid was significantly elevated compared to the surrounding normal tissue, while cDC2 cells significantly decreased. Hotspot and pseudotime trajectory analysis indicated two modules of macrophage cells (Module2: highly expresses RNASE1, C1QA, CD163, CD14, C1QC, FCGRT, MS4A7; Module10: highly expresses APOC1, CTSB, CTSL, TYROBP), which exhibited the characteristics of tumor-associated macrophages, were upregulated in more-advanced keloid cells. Subsequently, the analysis of cellular communication networks suggested that a macrophage-centered communication regulatory network may exist in keloids and that fibroblasts in keloids may facilitate the transition and proliferation of M2 macrophages, which contributes to further comprehension of the immunological features of keloids. Overall, we delineate the immunology landscape of keloids and present new insights into the mechanisms involved in its formation in this study.

Advances in the pathogenesis and clinical application prospects of tumor biomolecules in keloid.

Keloid scarring is a kind of pathological healing manifestation after skin injury and possesses various tumor properties, such as the Warburg effect, epithelial-mesenchymal transition (EMT), expression imbalances of apoptosis-related genes and the presence of stem cells. Abnormal expression of tumor signatures is critical to the initiation and operation of these effects. Although previous experimental studies have recognized the potential value of a single or several tumor biomolecules in keloids, a comprehensive evaluation system for multiple tumor signatures in keloid scarring is still lacking. This paper aims to summarize tumor biomolecules in keloids from the perspectives of liquid biopsy, genetics, proteomics and epigenetics and to investigate their mechanisms of action and feasibility from bench to bedside. Liquid biopsy is suitable for the early screening of people with keloids due to its noninvasive and accurate performance. Epigenetic biomarkers do not require changes in the gene sequence and their reversibility and tissue specificity make them ideal therapeutic targets. Nonetheless, given the ethnic specificity and genetic predisposition of keloids, more large-sample multicenter studies are indispensable for determining the prevalence of these signatures and for establishing diagnostic criteria and therapeutic efficacy estimations based on these molecules.

Giant pilomatrixoma with bullous appearance on the back: A case report and discussion of misdiagnosis.

Pilomatrixoma is a benign, asymptomatic skin tumor that forms from hair follicle matrix cells. Most are under 3 cm in diameter and occur on the head, face, or neck. Bullous appearance is very rare in pilomatrixoma. In this case report, we present a case of bullous pilomatrixoma of unusual size, region, symptoms, and patient age. It had been misdiagnosed as a keloid and as dermatofibrosarcoma protuberans. Early treatments were ineffective. The patient approached our outpatient facility and underwent excision. He was then diagnosed with pilomatrixoma by pathological examination. The clinical appearance of this case was quite difficult to diagnose, even MRI and B-ultrasonic examinations provided limited diagnostic evidence. Given the revelations from this case, we reemphasize the importance of performing a biopsy (if patients refused operation or preferred conservative treatment) before any invasive treatment to minimize economic or time loss of patients who have difficulties in diagnosis.

Fabrication of cobaltous telluride and carbon composite as a promising carrier for boosting electro oxidation of ethylene glycol on palladium in alkaline medium.

The development of highly active and earth-rich electrocatalysts remains a formidable challenge for the commercialization of fuel cells. Herein, a composite carrier composed of cobaltous telluride (CoTe) and carbon (C) has been designed for the first time to enhance the electrocatalytic performance of palladium (Pd) nanoparticles (NPs) for the electro-oxidation of ethylene glycol (EG). Remarkably, the mass activity for the as-prepared Pd/CoTe-C catalyst during the ethylene glycol oxidation reaction (EGOR) is found to reach up to 3917.3 mA mg-1, which is 2.2 times higher than that of Pd/Co-C (1785.0 mA mg-1) and 4.1 times greater than that of commercial Pd/C catalyst (962.4 mA mg-1), exceeding that obtained for most Pd-based electrocatalysts reported thus far. In particular, the Pd/CoTe-C catalyst shows better electrochemical stability toward the EGOR than the Pd/Co-C and commercial Pd/C catalysts. Thus, the Pd/CoTe-C electrocatalyst is expected to exhibit broad application prospects in the field of fuel cells.

Application and prospect of adipose stem cell transplantation in treating lymphedema.

BACKGROUND: Lymphedema is a chronic, debilitating and incurable disease that affects 0.13%-2% of the global population. Emerging evidence indicates that adipose-derived stem cells (ADSCs) might serve as suitable seed cells for lymphatic tissue engineering and lymphedema therapy. AIM: To summarize applications of ADSCs for treating lymphedema in both animal studies and clinical trials. METHODS: A systematic search was performed on four databases - PubMed, Clinicaltrials.gov, the evidence-based Cochrane Library, and OVID - using the following search string: ("lymphedema" or "lymphoedema" or "lymphangiogenesis") and ("adipose-derived stem cells" or "adipose-derived stromal cells" or "adipose-derived regenerative cells"). A manual search was performed by skimming the references of relevant studies. Animal studies and clinical trials using adipose-derived cells for the treatment of any kind of lymphedema were included. RESULTS: A total of eight research articles published before November 2019 were included for this analysis. Five articles focused on animal studies and another three focused on clinical trials. ADSC transplantation therapy was demonstrated to be effective against lymphedema in all studies. The animal studies found that coadministration of ADSCs and controlled-release vascular endothelial growth factor-C or platelet-rich plasma could improve the effectiveness of ADSC therapy. Three sequential clinical trials were conducted on breast cancer-related lymphedema patients, and all showed favorable results. CONCLUSION: ADSC-based therapy is a promising option for treating lymphedema. Large-scale, multicenter randomized controlled trials are needed to develop more effective and durable therapeutic strategies.

Effect of Clostridium perfringens enterotoxin on gastric cancer cells SGC7901 which highly expressed claudin-4 protein.

AIM: To investigate the effects of Clostridium perfringens enterotoxin (CPE) on gastric cancer cells which highly expressed claudin-4 (CL4) protein. METHODS: In this study, we detected expression of CL4 protein in different gastric cancer cell lines. Then, we investigated the effects of CPE on SGC7901 cells which highly expressed CL4 protein and the effects of CPE on subcutaneous tumor in nude mice models. RESULTS: CL4 are highly expressed in SGC7901 cells. CPE expressed significant cytotoxicity in SGC7901 cells. Suppression of CL4 expression significantly decreased CPE-mediated cytotoxicity. CPE also inhibited tumor growth in subcutaneous tumor xenograft models. CONCLUSION: CPE showed CL4 mediated cytotoxicity on gastric cancer cells SGC7901 and inhibited tumor growth in nude mice models.