Transcriptomic profiling of long non-coding RNAs in dermatomyositis by microarray analysis
SCIENTIFIC REPORTS
Authors: Peng, Qing-Lin; Zhang, Ya-Mei; Yang, Han-Bo; Shu, Xiao-Ming; Lu, Xin; Wang, Guo-Chun
Abstract
Long non-coding RNAs (lncRNAs) are prevalently transcribed in the genome and have been found to be of functional importance. However, the potential roles of lncRNAs in dermatomyositis (DM) remain unknown. In this study, a lncRNA + mRNA microarray analysis was performed to profile lncRNAs and mRNAs from 15 treatment-naive DM patients and 5 healthy controls. We revealed a total of 1198 lncRNAs (322 up-regulated and 876 down-regulated) and 1213 mRNAs (665 up-regulated and 548 down-regulated) were significantly differentially expressed in DM patients compared with the healthy controls (fold change > 2, P < 0.05). Subgrouping DM patients according to the presence of interstitial lung disease and anti-Jo-1 antibody revealed different expression patterns of the lncRNAs. Pathway and gene ontology analysis for the differentially expressed mRNAs confirmed that type 1 interferon signaling was the most significantly dysregulated pathway in all DM subgroups. In addition, distinct pathways that uniquely associated with DM subgroup were also identified. Bioinformatics prediction suggested that linc-DGCR6-1 may be a lncRNA that regulates type 1 interferon-inducible gene USP18, which was found highly expressed in the perifascicular areas of the muscle fibers of DM patients. Our findings provide an overview of aberrantly expressed lncRNAs in DM muscle and further broaden the understanding of DM pathogenesis.
Dual regulation of Stat1 and Stat3 by the tumor suppressor protein PML contributes to interferon alpha-mediated inhibition of angiogenesis
JOURNAL OF BIOLOGICAL CHEMISTRY
Authors: Hsu, Kuo-Sheng; Zhao, Xuan; Cheng, Xiwen; Guan, Dongyin; Mahabeleshwar, Ganapati H.; Liu, Yu; Borden, Ernest; Jain, Mukesh K.; Kao, Hung-Ying
Abstract
IFNs are effective in inhibiting angiogenesis in preclinical models and in treating several angioproliferative disorders. However, the detailed mechanisms of IFN alpha-mediated anti-angiogenesis are not completely understood. Stat1/2/3 and PML are IFN alpha downstream effectors and are pivotal regulators of angiogenesis. Here, we investigated PML's role in the regulation of Stat1/2/3 activity. In Pml knock-out (KO) mice, ablation of Pml largely reduces IFN alpha angiostatic ability in Matrigel plug assays. This suggested an essential role for PML in IFN alpha's anti-angiogenic function. We also demonstrated that PML shared a large cohort of regulatory genes with Stat1 and Stat3, indicating an important role of PML in regulating Stat1 and Stat3 activity. Using molecular tools and primary endothelial cells, we demonstrated that PML positively regulates Stat1 and Stat2 isgylation, a ubiquitination-like protein modification. Accordingly, manipulation of the isgylation system by knocking down USP18 altered IFN alpha-PML axis-mediated inhibition of endothelial cell migration and network formation. Furthermore, PMLpromotes turnover of nuclear Stat3, and knockdown of PML mitigates the effect of LLL12, a selective Stat3 inhibitor, on IFN alpha-mediated anti-angiogenic activity. Taken together, we elucidated an unappreciated mechanism in which PML, an IFN alpha-inducible effector, possess potent angiostatic activity, doing so in part by forming a positive feedforward loop with Stat1/2 and a negative feedback loop with Stat3. The interplay between PML, Stat1/Stat2, and Stat3 contributes to IFN alpha-mediated inhibition of angiogenesis, and disruption of this network results in aberrant IFN alpha signaling and altered angiostatic activity.