Therapeutic role of exosomes and conditioned medium in keloid and hypertrophic scar and possible mechanisms.

Exosomes, ranging from 40 to 160 nm in diameter, are extracellular lipid bilayer microvesicles that regulate the body's physiological and pathological processes and are secreted by cells that contain proteins, nucleic acids, amino acids and other metabolites. Previous studies suggested that mesenchymal stem cell (MSC)-derived exosomes could either suppress or support keloid and hypertrophic scar progression. Although previous research has identified the potential value of MSC-exosomes in keloid and hypertrophic scar, a comprehensive analysis of different sources of MSC-exosome in keloid and hypertrophic scar is still lacking. This review mainly discusses different insights regarding the roles of MSC-exosomes in keloid and hypertrophic scar treatment and summarizes possible underlying mechanisms.

Development and validation of ferroptosis-related lncRNA signature and immune-related gene signature for predicting the prognosis of cutaneous melanoma patients.

Ferroptosis, a form of cell death caused by iron-dependent peroxidation of lipids, plays an important role in cancer. Recent studies have shown that long noncoding RNAs (lncRNAs) are involved in the regulation of ferroptosis in tumor cells and are also closely related to tumor immunity. Immune cell infiltration in the tumor microenvironment affects the prognosis and clinical outcome of immunotherapy in melanoma patients, and immune cell classification may be able to accurately predict the prognosis of melanoma patients. However, the prognostic value of ferroptosis-related lncRNAs (FRLs) in melanoma has not been thoroughly explored, and it is difficult to define the immune characteristics of melanoma. We used The Cancer Genome Atlas (TCGA), the Genotype-Tissue Expression (GTEx) database, and the FerrDb database to identify FRLs. FRLs with prognostic value were evaluated in an experimental cohort utilizing univariate, LASSO (least absolute shrinkage and selection operator) and multivariate Cox regression, followed by in vitro assays evaluating the expression levels and the biological functions of three candidate FRLs. Kaplan-Meier (K-M) and receiver operating characteristic (ROC) curve analyses were used to assess the validity of the risk model, and the drug sensitivity of FRLs was examined by drug sensitivity analysis. The differentially expressed genes between the high- and low-risk groups in the risk model were enriched in the immune pathway, and we further found immune gene signatures (IRGs) that could predict the prognosis of melanoma patients through a series of methods including single-sample Gene Set Enrichment Analysis (ssGSEA). Finally, two GEO cohorts were used to validate the predictive accuracy and reliability of these two signature models. Our findings suggest that FRLs and IRGs have the potential to predict the prognosis of patients with cutaneous melanoma.

The role of tumor-associated macrophages and soluble mediators in pulmonary metastatic melanoma.

Skin malignant melanoma is a highly aggressive skin tumor, which is also a major cause of skin cancer-related mortality. It can spread from a relatively small primary tumor and metastasize to multiple locations, including lymph nodes, lungs, liver, bone, and brain. What's more metastatic melanoma is the main cause of its high mortality. Among all organs, the lung is one of the most common distant metastatic sites of melanoma, and the mortality rate of melanoma lung metastasis is also very high. Elucidating the mechanisms involved in the pulmonary metastasis of cutaneous melanoma will not only help to provide possible explanations for its etiology and progression but may also help to provide potential new therapeutic targets for its treatment. Increasing evidence suggests that tumor-associated macrophages (TAMs) play an important regulatory role in the migration and metastasis of various malignant tumors. Tumor-targeted therapy, targeting tumor-associated macrophages is thus attracting attention, particularly for advanced tumors and metastatic tumors. However, the relevant role of tumor-associated macrophages in cutaneous melanoma lung metastasis is still unclear. This review will present an overview of the origin, classification, polarization, recruitment, regulation and targeting treatment of tumor-associated macrophages, as well as the soluble mediators involved in these processes and a summary of their possible role in lung metastasis from cutaneous malignant melanoma. This review particularly aims to provide insight into mechanisms and potential therapeutic targets to readers, interested in pulmonary metastasis melanoma.