We aimed to identify an expression profile of lncRNAs potentially related to treatment response in Psoriatic arthritis (PsA) patients, to be used as potential genomic biomarkers predictors of drug treatment effectiveness. In addition, we evaluated a possible association between lncRNAs genetic variants and the response to therapy using the clinical parameter of Disease Activity Index. For the expression study, we collected 48 treated PsA patients, monitoring the treatment response for 12 months. We initially used PCR Array and, then, we validated the results with qRT-PCR. We also retrospectively genotyped 163 treated PsA patients. Firstly, we observed a significant difference in the expression level between Responder and non-Responder patients, of 4 lncRNAs in the group of PsA patients treated with TNFi and of 3 lncRNAs in the group of patients treated with IL17i. Then, we confirmed a significant decrease of MEG3 expression in non-Responder patients compared to Responders, also considering separately the single groups of patients treated with TNFi and IL17i. In addition, our results seem to highlight a potential dose-dependent effect of rs941576 (MEG3) variant allele on Disease Activity Index. Our study suggests a possible role of the lncRNA MEG3 in the treatment response to biological drugs.

BACKGROUND: LncRNA MEG3 expressed abnormally in various cancers including breast cancer, but no studies reported the correlation between MEG3 SNPs and breast cancer susceptibility among Chinese women.
METHODS: This study is aimed to explore the association between three SNPs of MEG3 (rs3087918, rs7158663, rs11160608) and breast cancer. The study is a population-based case-control study including 434 breast cancer patients and 700 healthy controls. Genotyping was performed using Sequenom MassArray technique. Function prediction of rs3087918 were based on RNAfold and lncRNASNP2 databases.
RESULTS: Pooled analysis indicated that rs3087918 was related to a decreased risk of breast cancer [GG vs. TT: OR (95%) = 0.67(0.45-0.99), P = 0.042; GG vs. TT + TG: OR (95%) = 0.69(0.48-0.99), P = 0.046], especially for women aged <=49 [GG vs. TT: OR (95%) = 0.40(0.22-0.73), P = 0.02]. Comparison between case groups showed genotype GG and TG/GG of rs3087918 were associated with her-2 receptor expression [GG vs. TT: OR (95%) = 2.37(1.24-4.63), P = 0.010; TG + GG vs. TT: OR (95%) = 1.50(1.01-2.24), P = 0.045]. We didn\'t find statistical significance for rs11160608, rs7158663 and breast cancer. Structure prediction based on RNAfold found rs3087918 may influence the secondary structure of MEG3. The results based on lncRNASNP2 indicated that rs3087918 may gain the targets of hsa-miR-1203 to MEG3, while loss the target of hsa-miR-139-3p and hsa-miR-5091 to MEG3.
CONCLUSIONS: MEG3 rs3087918 was associated with a decreased risk of breast cancer. MEG3 haplotype TCG may increase the risk of breast cancer.

Previous studies have indicated that long non-coding RNAs (lncRNAs) were closely related to diabetes. In this study, we aimed to explore the possible role and mechanism of lncRNA MEG3 in the occurrence and development of type 2 diabetes mellitus (T2DM) and its vascular complications. A case-control study involving 115 subjects was conducted, including 53 T2DM patients (37 patients with vascular complication and 16 patients without vascular complications) and 62 healthy subjects. We performed real-time polymerase chain reaction (RT-PCR) analysis of the lncRNA MEG3 and miR-146a levels in peripheral blood mononuclear cells (PBMCs) in the 115 samples. We found that the expression of lncRNA MEG3 was upregulated in the T2DM patients with vascular complication (DC group) compared with T2DM patients without vascular complication (D group) (P < 0.05) and the control group (P < 0.01). miR-146a levels in DC group were significantly lower compared with control group. There was a significant positive correlation between the expression of lncRNA MEG3 and glucose (GLU) (r = 0.301, P = 0.0011) and hemoglobin A1C (HbA1c) (r = 0.477, P = 0.0006). Our study suggests MEG3 may play as an important role in progression of diabetes-related vascular complications, contributing to a novel understanding of pathogenesis and prognosis for diabetes and its complications.

Accumulating evidence suggest that dysregulated expression of long non-coding RNA (lncRNA) plays a critical role in human tumorigenesis. However, little is known about the lncRNA implicated in the epithelial-to-mesenchymal transition (EMT) process. In this study, we performed data mining in The Cancer Genome Atlas (TCGA) hepatocellular carcinoma (HCC) data set and identified the a spectrum of differentially expressed lncRNAs implicated the EMT process of HCC, and functionally validated their roles in LM3 cells. Especially, lncRNA WDFY3-AS2-, LINC00472-, MIAT-, and MEG3-associated genes were significantly enriched in EMT-linked pathways. Loss-of-function study showed that genetic silencing of WDFY3-AS3, MIAT, and MEG3, but not LINC00472, resulted in reduced N-cadherin expression, cell migration, and cell invasion. Collectively, our results identify several lncRNAs that regulate the EMT process of HCC, which provides critical information for HCC tumorigenesis and potential therapeutic targets.

With the development of whole genome and transcriptome sequencing technologies, long noncoding RNAs (lncRNAs) have received increased attention. Multiple studies indicate that lncRNAs act not only as the intermediary between DNA and protein but also as important protagonists of cellular functions. LncRNAs can regulate gene expression in many ways, including chromosome remodeling, transcription and post-transcriptional processing. Moreover, the dysregulation of lncRNAs has increasingly been linked to many human diseases, especially in cancers. Here, we reviewed the rapidly advancing field of lncRNAs and described the relationship between the dysregulation of lncRNAs and human diseases, highlighting the specific roles of lncRNAs in human diseases.