This study assessed miR-675-3p-related regulatory mechanisms in melanoma and the clinical relevance of such regulatory activities. We downloaded miRNA mature strand expression RNA-Seq, phenotypic, and DNA methylation data pertaining to the TCGA Melanoma cohort. Differentially expressed miRNAs (DEMs) between metastatic and primary melanoma patient tissues were then identified, and miR-675-3p expression in melanoma patient peripheral blood was confirmed using the GSE20994 GEO dataset, while its expression in melanoma cell lines was evaluated via qRT-RCR. The clinical and prognostic implications of miR-675-3p in melanoma were assessed, and miR-675-3p target genes were identified using bioinformatics tools. Functional roles of this miRNA were explored via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. We identified 3 and 22 miRNAs that were up- and downregulated, respectively, in metastatic melanoma samples relative to primary melanoma samples. Upregulation of miR-675-3p was associated with poorer overall patient survival, tumor histologic grade, and Clark's level. Consistently, miR-675-3p was also overexpressed in the peripheral blood of melanoma patients relative to healthy controls, and in melanoma cell lines relative to control cells. Gene regulatory networks indicated that 32 transcription factors control miR-675-3p expression, and that it, in turn, regulates 10 target genes. KEGG analyses indicated that these genes were associated with cell cycle, transcriptional misregulation in cancer, TGF-beta signaling, and HIF-1 signaling pathways. Gain-of-function assays revealed that miR-675-3p could promote cell proliferation via accelerating cell cycle progression. Western blotting results indicated that miR-675-3p could active TGF-beta and HIF-1 signaling. Through upstream and downstream analyses of miR-675-3p-related regulatory activity, we confirmed that this miRNA participates in key melanoma-related processes and offers value as a prognostic biomarker in melanoma patients.

本研究评估了黑色素瘤中 miR-675-3p 相关的调控机制以及此类调控活动的临床相关性。我们下载了与 TCGA 黑色素瘤队列相关的 miRNA 成熟链表达 RNA-Seq、表型和 DNA 甲基化数据。然后鉴定了转移性和原发性黑色素瘤患者组织之间差异表达的 miRNA (DEM)，并使用 GSE20994 GEO 数据集确认了黑色素瘤患者外周血中 miR-675-3p 的表达，同时通过 qRT-RCR 评估了其在黑色素瘤细胞系中的表达. 评估了 miR-675-3p 在黑色素瘤中的临床和预后意义，并使用生物信息学工具确定了 miR-675-3p 靶基因。通过基因本体论 (GO) 和京都基因和基因组百科全书 (KEGG) 分析探索了该 miRNA 的功能作用。我们在转移性黑色素瘤样品中分别鉴定了 3 和 22 种 miRNA，它们相对于原发性黑色素瘤样品分别上调和下调。miR-675-3p 的上调与较差的总体患者存活率、肿瘤组织学分级和克拉克水平相关。一致地，相对于健康对照，黑色素瘤患者的外周血中以及相对于对照细胞的黑色素瘤细胞系中，miR-675-3p 也过表达。基因调控网络表明，有 32 个转录因子控制 miR-675-3p 的表达，进而调控 10 个靶基因。KEGG 分析表明，这些基因与细胞周期、癌症中的转录失调、TGF-β 信号传导和 HIF-1 信号传导通路有关。功能获得试验表明，miR-675-3p 可以通过加速细胞周期进程来促进细胞增殖。蛋白质印迹结果表明 miR-675-3p 可以激活 TGF-β 和 HIF-1 信号。通过对 miR-675-3p 相关调节活性的上游和下游分析，我们证实该 miRNA 参与关键的黑色素瘤相关过程，并作为黑色素瘤患者的预后生物标志物提供价值。