To identify how circular RNA circRNA_0082835 impacts melanoma cells and lymphatic metastasis to observe whether it exerts effects through its action mechanism of sponging microRNA miR-429. Clinical baseline information was collected, and clinical samples were used for detection on circRNA_0082835 and EZH2. The expression of circRNA_0082835, EZH2, and miR-429 was detected by quantitative real-time PCR (RT-qPCR). Cell proliferation was tested with cell counting kit-8 (CCK-8). Flow cytometry was applied to examination of cell cycle levels. Cell invasion and migration were observed by transwell and wound healing. The expression of Wnt/β-catenin pathway, cell cycle and epithelial-mesenchymal transition (EMT) marker proteins was analyzed by western blot. Dual-luciferase determined the binding of miR-429 and circ_0082835. As a result, the expression of circRNA_0082835 was increased and that of miR-429 was decreased with the increase in lymphatic metastasis level. CircRNA_0082835 expression was downregulated by circ_0082835 interference, upregulated by EZH2 interference and also downregulated after transfection of both shRNA-circ_0082835 and shRNA-EZH2. Inhibiting circ_0082835 and EZH2 suppressed the proliferation, invasion and migration, regulated the cell cycle levels, inhibited Wnt/βcatenin and attenuated EMT in melanoma cells. Inhibition of circ_0082835 and/or EZH2 elevated miR-429 expression. The binding among miR-429 and circ_0082835 was verified. MiR-429 inhibitor reversed the effect of circ_0082835 interference while having no significant impact on EZH2. In conclusion, circRNA_0082835 sponges miR-429 to affect the anti-tumor effect of miR-429 in primary melanoma and lymphatic metastasis.

Background: Current studies have revealed that RNA-binding protein RBM38 is closely related to tumor development, while its role in malignant melanoma remains unclear. Therefore, this research aimed to investigate the function of RBM38 in melanoma and the prognosis of the disease. Methods: Functional experiments (CCK-8 assay, cell colony formation, transwell cell migration/invasion experiment, wound healing assay, nude mouse tumor formation, and immunohistochemical analysis) were applied to evaluate the role of RBM38 in malignant melanoma. Immune-associated differentially expressed genes (DEGs) on RBM38 related immune pathways were comprehensively analyzed based on RNA sequencing results. Results: We found that high expression of RBM38 promoted melanoma cell proliferation, invasion, and migration, and RBM38 was associated with immune infiltration. Then, a five-gene (A2M, NAMPT, LIF, EBI3, and ERAP1) model of RBM38-associated immune DEGs was constructed and validated. Our signature showed superior prognosis capacity compared with other melanoma prognostic signatures. Moreover, the risk score of our signature was connected with the infiltration of immune cells, immune-regulatory proteins, and immunophenoscore in melanoma. Conclusions: We constructed an immune prognosis model using RBM38-related immune DEGs that may help evaluate melanoma patient prognosis and immunotherapy modalities.

Background In recent years, there has been growing evidence indicating a relationship between liquid–liquid phase separation (LLPS) and cancer development. However, to date, the clinical significance of LLPS in skin cutaneous melanoma (SKCM, hereafter referred to as melanoma) remains to be elucidated. In the current study, the impact of LLPS-related genes on melanoma prognosis has been explored. Methods LLPS-related genes were retrieved from the DrLLPS database. The prognostic feature for LLPS in melanoma was developed in The Cancer Genome Atlas (TCGA) dataset and verified in the GSE65904 cohort. Based on risk scores, melanoma patients were categorized into high- and low-risk groups. Thereafter, the differences in clinicopathological correlation, functional enrichment, immune landscape, tumor mutational burden, and impact of immunotherapy between the two groups were investigated. Finally, the role of key gene TROAP in melanoma was validated by in vitro and in vivo experiments. Results The LLPS-related gene signature was developed based on MLKL, PARVA, PKP1, PSME1, RNF114, and TROAP. The risk score was a crucial independent prognostic factor for melanoma and patients with high-risk scores were related to a worse prognosis. Approximately, all immune-relevant characteristics, such as immune cell infiltration and immune scores, were extremely evident in patients with low-risk scores. The findings from the in vitro and in vivo experiments indicated that the viability, proliferation, and invasion ability of melanoma cells were drastically decreased after the knockdown of TROAP. Conclusion Our gene signature can independently predict the survival of melanoma patients. It provides a basis for the exploration of the relationship between LLPS and melanoma and can offer a fresh perspective on the clinical diagnosis and treatment of the disease.