The biomarkers associated with epithelial-mesenchymal transition in human keloids.

INTRODUCTION: A keloid is a type of benign fibrotic disease with similar features to malignancies, including anti-apoptosis, over-proliferation, and invasion. Epithelial-mesenchymal transition (EMT) is a crucial mechanism that regulates the metastatic behavior of tumors. Thus, identifying EMT biomarkers is paramount in comprehensively understanding keloid pathogenesis. METHODS: To identify the differentially expressed genes (DEGs) GSE92566 dataset, with 3 normal skin and 4 keloid tissues, was downloaded from GEO databases to identify the differentially expressed genes (DEGs). Further, EMT-related genes were downloaded from dbEMT 2.0 databases and intersected with GSE92566 DEGs to identify EMT-related-DEGs (ERDEGs). Subsequently, the ERDEGs were used for GO, KEGG, gene set enrichment analysis (GSEA), protein-protein interaction (PPI), and miRNAs-mRNAs network analysis. To predict small molecules for EMT inhibition, the ERDEGs were imported to cMAP databases, whereas hub genes were imported to DGidb databases. Finally, we carried out qRT-PCR and in vitro experiments to validate our findings. RESULTS: A total of 122 ERDEGs were identified, including 59 upregulated and 63 down-regulated genes. Moreover, enrichment analysis revealed that focal adhesion, AMPK signal pathway, Wnt signal pathway, and EMT biological process were significantly enriched. STRING databases and Cytoscape software were used to construct the PPI network and EMT-related hub genes. Further, 3 modules were explored from the PPI network using the Molecular Complex Detection (MCODE) plugin. In the Cytohubba plugin, 10 hub genes were explored, including FN1, EGF, SOX9, CDH2, PROM1, EPCAM, KRT19, ITGB1, CD24, and KRT18. These genes were then enriched for the focal adhesion pathway. We constructed a microRNA (miRNA)-mRNA network, which predicted hsa-miR-155-5p (8 edges), hsa-miR-124-3p (7 edges), hsa-miR-145-5p (5 edges), hsa-miR-20a-5p (5 edges) and hsa-let-7b-5p (4 edges) as the most connected miRNAs regulating EMT. Based on the ERDEGs and 10 hub genes mentioned above, ribavirin demonstrated high drug-targeting relevance. Subsequently, qRT-PCR confirmed that the expression of FN1, ITGB1, CDH2, and EPCAM corroborated with previous findings. qRT-PCR also showed that the expression levels of hsa-miR-124-3p and hsa-miR-145-5p were significantly lower in keloids and hsa-miR-155-5p was upregulated in keloids. Finally, by treating human keloid fibroblasts (HKFs) with ribavirin in vitro, we confirmed that ribavirin could inhibit HKFs proliferation and EMT. CONCLUSION: In summary, this work provides novel EMT biomarkers in keloids and predicts new small target molecules for keloid therapy. Our findings improve the understanding of keloid pathogenesis, providing new treatment options.

2-Methoxyestradiol inhibits the proliferation level in keloid fibroblasts through p38 in the MAPK/Erk signaling pathway.

BACKGROUND: The MAPK/Erk signaling pathway is a classic pathway in cell proliferation. Our former study showed that keloid tissue revealed a higher proliferation level than physiological scars and normal skin. As a natural metabolite of estradiol, 2-methoxyestradiol (2ME2) showed an inhibition proliferation effect on tumor cells. AIM: In this study, the treatment effect of 2ME2 and its potential mechanisms are explored. METHODS: Six keloid patients and six non-keloid patients were randomly selected from the Department of Plastic Surgery at our hospital during June 2021 to December 2021. Six groups were established: normal skin fibroblasts (N); keloid fibroblasts (K); keloid fibroblasts treated with 2ME2 (K + 2ME2); keloid fibroblasts treated with dimethyl sulfoxide (DMSO) (K + DMSO); keloid fibroblasts treated with doramapimod (K + IN); keloid fibroblasts treated with doramapimod (p38 inhibitor) and 2ME2 (K + IN+2ME2). The fibroblast activity and key factor expression of the MAPK/Erk signaling pathway were measured. RESULTS: In the results, 2ME2 significantly inhibited keloid fibroblast activity and key factor expression (except STAT1). CONCLUSION: The proliferation levels were reduced by both the p38 inhibitor and 2ME2, indicating 2ME2 may achieve an antiproliferation effect by targeting p38 in keloid fibroblasts.

Role of HIF-1α in pathogenic mechanisms of keloids.

BACKGROUDS AND OBJECTIVE: Keloids are defined as overrepairing products that develop after skin lesions. Keloids are characterized by the proliferation of fibroblasts and the overaccumulation of extracellular matrix components (mainly collagen), leading to a locally hypoxic microenvironment. Hence, this article was aimed to review hypoxia in pathogenesis of keloids. METHODS: We reviewed and summarized the relevant published studies. RESULTS: Hypoxia results in the accumulation of hypoxia-inducible factor 1α (HIF-1α) in keloids, contributing to overactivation of the fibrotic signaling pathway, epithelial-mesenchymal transition, and changes in metabolism, eventually leading to aggravated fibrosis, infiltrative growth, and radiotherapy resistance. CONCLUSION: It is, therefore, essential to understand the role of HIF-1α in the pathogenic mechanisms of keloids in order to develop new therapeutic approaches.

A comparison of proliferation levels in normal skin, physiological scar and keloid tissue.

Proliferation is an important characteristic of life, and many signaling pathways participate in this complicated process. The MAPK/Erk pathway is a classic pathway in cell proliferation. In this study, expression levels of key factors in the MAPK/Erk pathway were measured to assess the proliferation level among normal skin, physiological scar, and keloid tissue. Thirty patients were selected randomly from the Department of Plastic Surgery at Peking Union Medical College Hospital from January 2019 to December 2020. Histological appearance and fiber tissue content were observed by Hematoxylin and eosin staining and Masson staining. Expression levels of key factors in the MAPK/Erk pathway (ATF2, c-Jun, c-Myc, p38 and STAT1) and relative proteins (HIF-1α and PCNA) in tissues were detected by immunohistochemistry and analyzed as the percentage of positively stained cells in both the tissue epidermis and dermis. Western blot was used for quantitative analysis of the above factors. In results, keloid tissue showed a significantly higher fiber and less cell content. In the immunohistochemical result, higher expression of key factors was observed in the epidermis than in the dermal layer, and the expression of all factors was increased remarkably in keloid tissue. In western blot analysis, all factors (except STAT1) showed higher expression in keloid tissue. In our former research, keloid showed similar apoptosis level as physiological scar and normal skin. On combining our former conclusion and results in this study, an imbalance condition between the high proliferation level and normal apoptosis level may lead to the growth characteristics of keloid.

A new photodynamic therapy photosensitizer (p1) promotes apoptosis of keloid fibroblasts by targeting caspase-8.

Photodynamic therapy (PDT) is a new therapy for treating cancer with less toxicity, high selectivity, good cooperativity, and repetitive usability. However, keloid treatment by PDT is mainly focused on clinical appearance, and few studies have been conducted on the mechanisms of PDT. In this study, key factors of the classical mitochondrial apoptosis signaling pathway were measured to assess the effect of a new PDT photosensitizer (p1). A specific inhibitor of caspase-8 (Z-IETD-FMK) was also used to verify the possible mechanisms. Twelve samples were obtained from 12 patients (six with keloids and six without) selected randomly from the Department of Plastic Surgery at Peking Union Medical College Hospital from January to December 2020. After cell culture, fibroblasts were divided into 13 groups. The morphology of fibroblasts in each group was observed by microscopy. Cell activity was measured by cell counting kit-8, and cell apoptotic morphology was observed by TUNEL staining. The reactive oxygen species (ROS) relative value was measured by a ROS test kit. The expression levels of key mitochondrial factors (caspase-3, caspase-8, cytochrome-c, Bax, and Bcl-2) were assessed by western blot, and mRNA expression of caspase-3 and caspase-8 was measured by RT-qPCR. We showed that p1 had a satisfactory proapoptotic effect on keloid fibroblasts by increasing the expression of ROS, caspase-3, caspase-8, and cytochrome-c, and decreasing the Bcl-2/Bax ratio; however, this effect was partially inhibited by Z-IETD-FMK, indicating that caspase-8 may be one of the p1's targets to achieve the proapoptotic effect.

Sensitization of keloid fibroblasts by quercetin through the PI3K/Akt pathway is dependent on regulation of HIF-1α.

Keloids are raised, red, hard and irregular tumors that are prone to extend beyond the wound borders. Surgical excision is not sufficient to eradicate a keloid. Adjuvant therapy with radiation is a recommended treatment that reportedly achieves improved efficacy. However, radiation does not only kill cells in the keloid tissue but also stimulates their resistance, and intractable cases can display continuous recurrence. Quercetin was initially extracted from natural products and is used as a dietary supplement. The role of quercetin as an oxidant scavenger has been highlighted in many studies and has drawn interest to the application of ionizing radiation (IR) sensitization. In this study, we first demonstrate that keloid fibroblasts acquire resistance after IR treatment, and this can be relieved by treatment with quercetin. Further, we showed that hypoxia-inducible factor 1 (HIF-1), a prognostic marker used in clinical practice after radiation therapy, was associated with stronger radioresistance in keloid fibroblasts, which was downregulated after quercetin treatment. The inhibition of HIF-1 expression by quercetin was found to be dependent on the phosphatidylinositol-3-kinase (PI3K)/Akt pathway. Quercetin has been reported to reduce the phosphorylation of Akt. Taken together, we revealed one mechanism underlying the suppression of radioresistance by quercetin, which involved the regulation of HIF-1α by the PI3K/Akt pathway. Our study provides a molecular basis for the application of quercetin in radiation sensitization in the treatment of keloids.

MicroRNA-21 antisense oligonucleotide improves the sensitivity of A375 human melanoma cell to Cisplatin: An in vitro study.

This study explored Cisplatin resistance effect of microRNA-21 (miR-21) antisense oligonucleotide (AS-ODN) in human melanoma A375 cell. AS-ODN was transfected in melanoma A375 cells and Cisplatin-resistant cell line A375/CDDP, and divided into the AS-ODN, nonsense oligonucleotide (NS-ODN) and normal groups. Cell ultrastructure changes were observed through transmission electron microscope. MiR-21 AS-ODN could be tested cell growth effect in different time periods by trypan blue exclusion. MiR-21 mRNA expression change was detected by quantitative fluorescence PCR. Cell apoptosis, cycle distribution and miR-21 AS-ODN effect on proliferation and Cisplatin sensitivity were tested by flow cytometry, MTT assay, TUNEL, and Clonogenic assay. Cell apoptosis was observed after transfection 24 h with the AS-ODN group, while the NS-ODN and normal group cells had no apoptotic symptoms; Compared with the normal group, the AS-ODN group began to show obvious cell growth inhibition effect after transfection 24 h lasting 72 h (all P < 0.05), but the NS-ODN group had no significant difference (P > 0.05). miR-21 mRNA expression in the AS-ODN group was obviously decreased with rising apoptosis rate (all P < 0.05) and there was no significant difference in the NS-ODN group (P > 0.05). MiR-21 AS-ODN could remarkably increase A375 cell and A375/CDDP cell sensitivity to Cisplatin (P < 0.05), while A375 cell sensitivity to Cisplatin between the NS-ODN group and the normal group had no difference. MiR-21 AS-ODN decreased IC50 and increased Cisplatin sensitivity for A375 cells and A375/CDDP cells, which would be a new target of melanoma treatment.

A comparison of apoptosis levels in keloid tissue, physiological scars and normal skin.

Apoptosis is a process of programmed cell death that occurs in multicellular organisms. The mitochondrial pathway plays a paramount role in apoptosis. In this study, the expression levels of key factors in the mitochondrial pathway and the cell proliferation factor (PCNA) were measured to evaluate the level of apoptosis and proliferation in keloid scars, physiological scars and normal skin tissue. Thirty samples were taken from 30 patients: 10 keloid patients, 10 physiological scar patients and 10 patients without obvious scarring. All 30 patients were selected randomly from the Department of Plastic Surgery at Peking Union Medical College Hospital from June 2016 to December 2016. Hematoxylin and eosin staining and Masson staining were used to observe the differences in histology and fiber tissue content. Mitochondrial pathway factors (caspase-3, caspase-8, caspase-9, Bcl-2, Bax, cytochrome-c) and PCNA expression levels were detected by immunohistochemistry and were analyzed as the percentage of positively stained cells in the epidermis and dermis. Relative protein expression levels were measured by western blotting. Compared with physiological scars and normal skin tissue, keloid tissue had an increase in fiber number and decrease in cell content. In our immunohistochemical and western blot analyses, all tissue types showed similar expression levels of the mitochondrial pathway factors. However, the percentage of PCNA-positive cells and the relative protein expression level of PCNA were significantly higher in keloid tissue. Keloid has a similar apoptosis level as physiological scars and normal skin but has a higher expression of PCNA, indicating that keloid scars have high levels of proliferation and normal apoptosis.

[Acellular cadaveric dermis-assisted immediate breast reconstruction: the preliminary experience].

OBJECTIVE: To investigate the feasibility and therapeutic effect of acellular cadaveric dermis (ACD)-assisted immediate breast reconstruction. METHODS: From Sep. 2009 to May 2010, 10 cases received ACD-assisted immediate breast reconstruction. During the operation, the ACD was used to cover inferior and lateral portion of the implants in 2 cases and expanders in 8 cases. RESULTS: The patients were followed up for an average period of 4 months with satisfactory breast appearance. The complications included infection in 2 cases and dehiscence in 2 cases. But no implant or expander was taken out. CONCLUSIONS: The ACD-assisted immediate breast reconstruction is a technically simple procedure with minimal morbidity. Satisfactory clinical outcome can be achieved with appropriate candidates.

[The technique of periorbital defects reconstruction with island orbicularis oculi myocutaneous flap in orbital zone].

OBJECTIVE: To investigate the technique of periorbital defects reconstruction with island orbicularis oculi myocutaneous flap in orbital zone. METHODS: The upper or lower eyelid island orbicularis oculi myocutaneous flap,medially based,were used for the defects of the periorbital area, according to the position,shape and size of the defects. The donor site was closed directly. RESULTS: From July 2003 to October 2009, 24 patients were treated in this method, the flaps survived totally. The flap proved to be flexible, safe, relatively simple, and provided good functional and aesthetic results with follow up 6 to 24 months. Complications were minimal. CONCLUSIONS: The upper eyelid or lower eyelid island orbicularis oculi myocutaneous flap, medially based, is a satisfied method in repairing periorbital defects in one stage with good blood supply, excellent color texture matching and inconspicuous donor scar and deformity.