Malignant melanoma is fatal in its metastatic stage. It is therefore essential to unravel the molecular mechanisms that govern disease progression to metastasis. MicroRNAs (miRs) are endogenous non‐coding RNAs involved in tumourigenesis. Using a melanoma progression model, we identified a novel pathway controlled by miR‐214 that coordinates metastatic capability. Pathway components include TFAP2C, homologue of a well‐established melanoma tumour suppressor, the adhesion receptor ITGA3 and multiple surface molecules. Modulation of miR‐214 influences in vitro tumour cell movement and survival to anoikis as well as extravasation from blood vessels and lung metastasis formation in vivo. Considering that miR‐214 is known to be highly expressed in human melanomas, our data suggest a critical role for this miRNA in disease progression and the establishment of distant metastases. There is a [Have you seen?][1] (May 2011) associated with this Article. [1]: http://dx.doi.org/10.1038/emboj.2011.132

Objective— Inflammatory stimuli released into atherosclerotic plaque microenvironment regulate vessel formation by modulating gene expression and translation. microRNAs are a class of short noncoding RNAs, acting as posttranscriptional regulators of protein-coding genes involved in various biological processes, including vascular cell biology. Among them, microRNA-221/222 (miR-221/222) seem to negatively modulate vascular remodeling by targeting different target genes. Here, we investigated their potential contribution to inflammation-mediated neovessel formation. Methods and Results— We used quantitative real-time RT-PCR amplification to analyze expression of 7 microRNAs previously linked to vascular biology, such as miR-17-5p, miR-21, miR-126, miR-210, miR-221, miR-222, and miR-296 and found high levels of expression for all of them in quiescent endothelial cells. However, miR-126, miR-221, miR-222, and miR-296 turned out to be down-modulated in endothelial cells exposed to inflammatory stimuli. Applying a gain-of-function approach, we demonstrated that, among them, only miR-222 was involved in inflammation-mediated vascular remodeling. In addition, we identified signal transducer and activator of transcription 5A (STAT5A) as a bona fide target of miR-222 and observed that miR-222 negatively correlated with STAT5A expression in human endothelial cells from advanced neovascularized atherosclerotic lesions. Conclusion— We identified STAT5A as a novel miR-222 target, and this finding opens up new perspectives for treatment of vascular diseases.

PD-L1 up-regulation in melanoma increases disease aggressiveness and is mediated through miR-17-5p