Genetic variants in long non-coding RNA MIAT contribute to risk of paranoid schizophrenia in a Chinese Han population

Genetic association between long non-coding RNA MIAT polymorphism and ischemic stroke susceptibility in the Chinese population

OBJECTIVES

The genetic association of long non-coding RNAs (lncRNAs) polymorphism with ischemic stroke (IS) susceptibility is not fully understood. To explore whether lncRNA MIAT rs1894720 polymorphism can predict the susceptibility of IS in the Chinese Han population.

MATERIALS AND METHODS

200 IS cases and 200 healthy controls were enrolled. Serum MIAT levels were tested via qRT-PCR. Rs1894720 genotyping was accomplished through Sanger sequencing.

RESULTS

MIAT rs1894720 genotypes were differentially distributed in IS and control groups. Rs1894720 TT genotype was considered to be a protective factor for IS risk in dominant model (GT + TT vs GG: OR = 0.630, 95 % CI = 0.412-0.962, P = 0.032). Further stratification results showed that individuals carrying the rs1894720 G allele in people older than 65 years, men, smokers, or those with hypertension had a higher risk of IS. MIAT rs1894720 GG genotype was positively related to the susceptibility to IS of LAA subtype compared with the healthy controls. GG genotype carriers had high serum MIAT levels compared to those with GT and TT genotypes.

CONCLUSIONS

MIAT rs1894720 polymorphism was associated with the risk of IS in the Chinese Han population, especially for LAA subtype. Rs1894720 GG genotype carriers were at greater risk of developing IS.

The Association Between Functional Variants in Long Non-coding RNAs and the Risk of Autism Spectrum Disorder Was Not Mediated by Gut Microbiota

The effect of functional variants in long non-coding RNA (lncRNA) gene regions on autism spectrum disorder (ASD) remains unclear. The present study aimed to investigate the association of functional variants located in lncRNA genes with the risk of ASD and explore whether gut microbiota would mediate the relationship. A total of 87 cases and 71 healthy controls were enrolled in the study. MassARRAY platform and 16S rRNA sequencing were respectively applied to assess the genotype of candidate SNPs and gut microbiota of children. The logistic regression models showed that the association between rs2295412 and the risk of ASD was statistically significant after Bonferroni adjustments. The risk of ASD decreased by 19% for each additional C allele carried by children in multiplicative models (OR = 0.81, 95% CI, 0.69-0.94, P = 0.007). Although we identified significant correlations between rs8113922 polymorphisms, Bifidobacteriales, and ASD, the mediating effect of gut microbiota on the relationship of the polymorphisms with the risk of ASD was not significant. The findings demonstrated that functional variants in lncRNA genes play an important role in ASD and gut microbiota could not mediate the association. Future studies are warranted to verify the results and search for more possible mechanisms of variants located in lncRNA genes implicated in ASD.

Puzzling out the role of MIAT LncRNA in hepatocellular carcinoma

A non-negligible part of our DNA has been proven to be transcribed into non-protein coding RNA and its intricate involvement in several physiological processes has been highly evidenced. The significant biological role of non-coding RNAs (ncRNAs), including long non-coding RNAs (lncRNAs) has been variously reported. In the current review, the authors highlight the multifaceted role of myocardial infarction-associated transcript (MIAT), a well-known lncRNA, in hepatocellular carcinoma (HCC). Since its discovery, MIAT has been described as a regulator of carcinogenesis in several malignant tumors and its overexpression predicts poor prognosis in most of them. At the molecular level, MIAT is closely linked to the initiation of metastasis, invasion, cellular migration, and proliferation, as evidenced by several in-vitro and in-vivo models. Thus, MIAT is considered a possible theranostic agent and therapeutic target in several malignancies. In this review, the authors provide a comprehensive overview of the underlying molecular mechanisms of MIAT in terms of its downstream target genes, interaction with other classes of ncRNAs, and potential clinical implications as a diagnostic and/or prognostic biomarker in HCC.

Downregulation of lncRNAs Gomafu, NONMMUT033604.2, and NONMMUT064397.2 in the hippocampus of mice with model of post-traumatic stress disorder

OBJECTIVES

Molecular mechanisms of post-traumatic stress disorder (PTSD) development have been analysed by evaluati-ng changes in the expression level of long non-coding RNA (lncRNA) as a potential biomarker of the disease and as one of the molecular aspects associated with the disease development.

METHODS

In our study, we used quantitative polymerase chain reaction (qPCR) to evaluate changes in the expression level of long non-coding RNA - Gomafu, NONMMUT033604.2, and NONMMUT064397.2 - in the hippocampus of mice that were subjected to an artificially induced middle single prolonged stress (mSPS) model of post-traumatic stress disorder.

RESULTS

We found a significant reduction in the expression levels of each of the three lncRNAs tested: Gomafu in 45.4 times, NONMMUT033604.2 in 53.4 times, and NONMMUT064397.2 in 5.2 times. The results of the present study provide evidence that the mSPS model effectively induces PTSD-like behaviour in mice leading to a significant decrease in the expression level of Gomafu, NONMMUT033604.2 and NONMMUT064397.2 lncRNA in mice hippocampus.

CONCLUSIONS

This data provides evidence that the three studied lncRNAs could be potential biomarkers of PTSD development.

MIAT LncRNA: A multifunctional key player in non-oncological pathological conditions

The discovery of non-coding RNAs (ncRNAs) has unveiled a wide range of transcripts that do not encode proteins but play key roles in several cellular and molecular processes. Long noncoding RNAs (lncRNAs) are specific class of ncRNAs that are longer than 200 nucleotides and have gained significant attention due to their diverse mechanisms of action and potential involvement in various pathological conditions. In the current review, the authors focus on the role of lncRNAs, specifically highlighting the Myocardial Infarction Associated Transcript (MIAT), in non-oncological context. MIAT is a nuclear lncRNA that has been directly linked to myocardial infarction and is reported to control post-transcriptional processes as a competitive endogenous RNA (ceRNA) molecule. It interacts with microRNAs (miRNAs), thereby limiting the translation and expression of their respective target messenger RNA (mRNA) and regulating protein expression. Yet, MIAT has been implicated in other numerous pathological conditions such as other cardiovascular diseases, autoimmune disease, neurodegenerative diseases, metabolic diseases, and many others. In this review, the authors emphasize that MIAT exhibits distinct expression patterns and functions across different pathological conditions and is emerging as potential diagnostic, prognostic, and therapeutic agent. Additionally, the authors highlight the regulatory role of MIAT and shed light on the involvement of lncRNAs and specifically MIAT in various non-oncological pathological conditions.

lncRNA-MIAT rs9625066 polymorphism could be a potential biomarker for ischemic stroke

BACKGROUND

Ischemic stroke (IS) is a common and serious neurological condition that is highly fatal but so far no early diagnostic markers are available. Myocardial infarction-associated transcript (MIAT) is a long non-coding RNA (lncRNA) that could lead to IS by inducing autophagy and apoptosis in neuronal cells. However, there has been no report on the link between susceptibility to IS and the single-nucleotide polymorphisms (SNPs) of MIAT. This study aimed to investigate the association between MIAT gene polymorphisms and IS risk.

METHODS

A total of 320 IS patients and 310 age-, sex- and race-matched controls were included in this study. Four polymorphisms (rs2157598, rs5761664, rs1894720, and rs9625066) were genotyped by using SNPscan technique.

RESULTS

Among the 4 polymorphisms of MIAT, only rs9625066 was associated with IS risk (CA vs. CC: adjusted OR = 0.55, 95% CI, 0.37-0.85, P = 0.006; AA vs. CC: adjusted OR = 0.39, 95% CI, 0.16-0.94, P = 0.036; (AA + CA vs. CC: adjusted OR = 0.53, 95% CI, 0.35-0.80, P = 0.002; A vs. C adjusted OR = 0.59, 95% CI, 0.42-0.82, P = 0.002). Haplotype analysis showed a 1.32-fold increase (95% CI, 1.05-1.67, P = 0.017) in IS risk for rs2157598-rs5761664-rs1894720-rs9625066 (A-C-G-C). Logistic regression analysis identified some independent impact factors for IS including rs9625066 AA/AC, TC, TG, HDL-C (P < 0.05).

CONCLUSION

The rs9625066 polymorphism of MIAT might be associated with IS susceptibility in Chinese population, in which AA/CA plays a protective role in IS, whereas the CC genotype increases the risk of developing IS, suggesting it might be a marker predictive of IS risk.

Long non-coding RNAs in schizophrenia: Genetic variations, treatment markers and potential targeted signaling pathways

Schizophrenia (SZ), a complex and debilitating spectrum of psychiatric disorders, is now mainly attributed to multifactorial etiology that includes genetic and environmental factors. Long non-coding RNAs (lncRNAs) are gaining popularity as a way to better understand the comprehensive mechanisms beneath the clinical manifestation of SZ. Only in recent years has it been elucidated that mammalian genomes encode thousands of lncRNAs. Strikingly, roughly 30-40% of these lncRNAs are extensively expressed in different regions across the brain, which may be closely associated with SZ. The therapeutic and adverse effects of atypical antipsychotic drugs (AAPDs) are partially reflected by their role in the regulation of lncRNAs. This begs the question directly, do any lncRNAs exist as biomarkers for AAPDs treatment? Furthermore, we comprehend a range of mechanistic investigations that have revealed the regulatory roles for lncRNAs both involved in the brain and the periphery of SZ. More crucially, we also combine insights from a variety of signaling pathways to argue that lncRNAs probably play critical roles in SZ via their interactive downstream factors. This review provides a thorough understanding regarding dysregulation of lncRNAs, corresponding genetic alternations, as well as their potential regulatory roles in the pathology of SZ, which might help reveal useful therapeutic targets in SZ.

The human lncRNA GOMAFU suppresses neuronal interferon response pathways affected in neuropsychiatric diseases

Long noncoding RNAs (lncRNAs) play multifaceted roles in regulating brain gene networks. LncRNA abnormalities are thought to underlie the complex etiology of numerous neuropsychiatric disorders. One example is the human lncRNA gene GOMAFU, which is found dysregulated in schizophrenia (SCZ) postmortem brains and harbors genetic variants that contribute to the risk of SCZ. However, transcriptome-wide biological pathways regulated by GOMAFU have not been determined. How GOMAFU dysregulation contributes to SCZ pathogenesis remains elusive. Here we report that GOMAFU is a novel suppressor of human neuronal interferon (IFN) response pathways that are hyperactive in the postmortem SCZ brains. We analyzed recently released transcriptomic profiling datasets in clinically relevant brain areas derived from multiple SCZ cohorts and found brain region-specific dysregulation of GOMAFU. Using CRISPR-Cas9 to delete the GOMAFU promoter in a human neural progenitor cell model, we identified transcriptomic alterations caused by GOMAFU deficiency in pathways commonly affected in postmortem brains of SCZ and autism spectrum disorder (ASD), with the most striking effects on upregulation of numerous genes underlying IFN signaling. In addition, expression levels of GOMAFU target genes in the IFN pathway are differentially affected in SCZ brain regions and negatively associated with GOMAFU alterations. Furthermore, acute exposure to IFN-γ causes a rapid decline of GOMAFU and activation of a subclass of GOMAFU targets in stress and immune response pathways that are affected in SCZ brains, which form a highly interactive molecular network. Together, our studies unveiled the first evidence of lncRNA-governed neuronal response pathways to IFN challenge and suggest that GOMAFU dysregulation may mediate environmental risks and contribute to etiological neuroinflammatory responses by brain neurons of neuropsychiatric diseases.

Rac1 and Rac3 GTPases and TPC2 are required for axonal outgrowth and migration of cortical interneurons

Rho GTPases, among them Rac1 and Rac3, are major transducers of extracellular signals and are involved in multiple cellular processes. In cortical interneurons, the neurons that control the balance between excitation and inhibition of cortical circuits, Rac1 and Rac3 are essential for their development. Ablation of both leads to a severe reduction in the numbers of mature interneurons found in the murine cortex, which is partially due to abnormal cell cycle progression of interneuron precursors and defective formation of growth cones in young neurons. Here, we present new evidence that upon Rac1 and Rac3 ablation, centrosome, Golgi complex and lysosome positioning is significantly perturbed, thus affecting both interneuron migration and axon growth. Moreover, for the first time, we provide evidence of altered expression and localization of the two-pore channel 2 (TPC2) voltage-gated ion channel that mediates Ca2+ release. Pharmacological inhibition of TPC2 negatively affected axonal growth and migration of interneurons. Our data, taken together, suggest that TPC2 contributes to the severe phenotype in axon growth initiation, extension and interneuron migration in the absence of Rac1 and Rac3.

The rs3931283/PVT1 and rs7158663/MEG3 polymorphisms are associated with diabetic kidney disease and markers of renal function in patients with type 2 diabetes mellitus

BACKGROUND

Long non-coding RNAs (lncRNAs) are key regulators of gene expression. Some studies have reported the association of polymorphisms in lncRNA genes with diabetes mellitus (DM) and its chronic complications, including diabetic kidney disease (DKD); however, the results are still inconclusive. Thus, we investigated the association of the rs3200401/MALAT1, rs1894720/MIAT, rs3931283/PVT1, rs11993333/PVT1, rs5749201/TUG1, and rs7158663/MEG3 polymorphisms with DKD in patients with type 2 DM (T2DM).

METHODS AND RESULTS

This study comprised 902 patients with T2DM and DKD (cases) and 394 patients with T2DM without DKD (controls). The six polymorphisms of interest were genotyped by real-time PCR using TaqMan probes. Frequency of the rs3931283/PVT1 G/G genotype was 36.2% in cases and 31.9% in controls (P = 0.331). After adjustment for gender, glycated hemoglobin, HDL cholesterol, ethnicity, hypertension, and diabetic retinopathy, the G/G genotype was associated with risk for DKD (OR = 1.625, 95% CI 1.020-2.588; P = 0.041). The rs3931283/PVT1 G/G genotype was also associated with higher urinary albumin excretion levels compared to A allele carriers (P = 0.017). No difference was found in rs7158663/MEG3 genotype frequencies between T2DM controls and DKD patients (OR = 1.087, 95% CI 0.686-1.724; P = 0.722). However, the rs7158663/MEG3 G/G genotype was associated with protection against severe DKD (OR = 0.694, 95% CI 0.488-0.989; P = 0.043, for patients with severe DKD vs. T2DM controls). The rs7158663/MEG3 G/G genotype was also associated with lower creatinine levels (P = 0.007) and higher estimated glomerular filtration rate (P = 0.010) compared to A allele carriers. No association was found between the rs11993333/PVT1, rs3200401/MALAT1, rs1894720/MIAT, and rs5749201/TUG1 polymorphisms and DKD or its laboratory markers.

CONCLUSION

The rs3931283/PVT1 G/G and rs7158663/MEG3 G/G are associated with DKD and markers of renal function in T2DM patients from a Brazilian population.

Functional Relationships between Long Non-Coding RNAs and Estrogen Receptor Alpha: A New Frontier in Hormone-Responsive Breast Cancer Management

In the complex and articulated machinery of the human genome, less than 2% of the transcriptome encodes for proteins, while at least 75% is actively transcribed into non-coding RNAs (ncRNAs). Among the non-coding transcripts, those ≥200 nucleotides long (lncRNAs) are receiving growing attention for their involvement in human diseases, particularly cancer. Genomic studies have revealed the multiplicity of processes, including neoplastic transformation and tumor progression, in which lncRNAs are involved by regulating gene expression at epigenetic, transcriptional, and post-transcriptional levels by mechanism(s) that still need to be clarified. In breast cancer, several lncRNAs were identified and demonstrated to have either oncogenic or tumor-suppressive roles. The functional understanding of the mechanisms of lncRNA action in this disease could represent a potential for translational applications, as these molecules may serve as novel biomarkers of clinical use and potential therapeutic targets. This review highlights the relationship between lncRNAs and the principal hallmark of the luminal breast cancer phenotype, estrogen receptor α (ERα), providing an overview of new potential ways to inhibit estrogenic signaling via this nuclear receptor toward escaping resistance to endocrine therapy.

Miat and interacting protein Metadherin maintain a stem-like niche to promote medulloblastoma tumorigenesis and treatment resistance

Long noncoding RNAs (lncRNAs) play essential roles in the development and progression of many cancers. However, the contributions of lncRNAs to medulloblastoma (MB) remain poorly understood. Here, we identify Miat as an lncRNA enriched in the sonic hedgehog group of MB that is required for maintenance of a treatment-resistant stem-like phenotype in the disease. Loss of Miat results in the differentiation of tumor-initiating, stem-like MB cells and enforces the differentiation of tumorigenic stem-like MB cells into a nontumorigenic state. Miat expression in stem-like MB cells also facilitates treatment resistance by down-regulating p53 signaling and impairing radiation-induced cell death, which can be reversed by therapeutic inhibition of Miat using antisense oligonucleotides. Mechanistically, the RNA binding protein Metadherin (Mtdh), previously linked to resistance to cytotoxic therapy in cancer, binds to Miat in stem-like MB cells. Like the loss of Miat, the loss of Mtdh reduces tumorigenicity and increases sensitivity to radiation-induced death in stem-like MB cells. Moreover, Miat and Mtdh function to regulate the biogenesis of several microRNAs and facilitate tumorigenesis and treatment resistance. Taken together, these data reveal an essential role for the lncRNA Miat in sustaining a treatment-resistant pool of tumorigenic stem-like MB cells.

The Long Non-Coding RNA GOMAFU in Schizophrenia: Function, Disease Risk, and Beyond

Neuropsychiatric diseases are among the most common brain developmental disorders, represented by schizophrenia (SZ). The complex multifactorial etiology of SZ remains poorly understood, which reflects genetic vulnerabilities and environmental risks that affect numerous genes and biological pathways. Besides the dysregulation of protein-coding genes, recent discoveries demonstrate that abnormalities associated with non-coding RNAs, including microRNAs and long non-coding RNAs (lncRNAs), also contribute to the pathogenesis of SZ. lncRNAs are an actively evolving family of non-coding RNAs that harbor greater than 200 nucleotides but do not encode for proteins. In general, lncRNA genes are poorly conserved. The large number of lncRNAs specifically expressed in the human brain, together with the genetic alterations and dysregulation of lncRNA genes in the SZ brain, suggests a critical role in normal cognitive function and the pathogenesis of neuropsychiatric diseases. A particular lncRNA of interest is GOMAFU, also known as MIAT and RNCR2. Growing evidence suggests the function of GOMAFU in governing neuronal development and its potential roles as a risk factor and biomarker for SZ, which will be reviewed in this article. Moreover, we discuss the potential mechanisms through which GOMAFU regulates molecular pathways, including its subcellular localization and interaction with RNA-binding proteins, and how interruption to GOMAFU pathways may contribute to the pathogenesis of SZ.

Genome-wide association studies-supported rs12966547 variant of the long noncoding RNA LOC105372125 is significantly associated with susceptibility to schizophrenia and bipolar disorder in Han Chinese women

OBJECTIVE

Genome-wide association studies have found that rs12966547 polymorphism was associated with susceptibility to schizophrenia in European populations. Recent studies showed that a genetic overlap may exist in schizophrenia and bipolar disorder. Here, we analyzed the associations between LOC105372125 rs12966547 polymorphism and schizophrenia and bipolar disorder in the Han Chinese population.

METHODS

Our study recruited 548 schizophrenia patients, 512 bipolar disorder patients, and 598 healthy controls. Genotyping of rs12966547 were performed using the Sequenom MassARRAY platform.

RESULTS

A significant association between rs12966547 polymorphism and susceptibility to bipolar disorder was observed after adjusting for sex and age (additive model: Padj = 0.040, recessive model: Padj = 0.044). However, no significant association was found between rs12966547 polymorphism and schizophrenia risk (all P > 0.05). In the analysis of gender, rs12966547 polymorphism was significantly associated with bipolar disorder (additive model: Padj = 0.027) and schizophrenia (dominant model: Padj = 0.039) in women. However, no significant association was found between rs12966547 polymorphism and the risk of bipolar disorder or schizophrenia in men (all Padj > 0.05).

CONCLUSIONS

Polymorphism of rs12966547 on the long noncoding RNA LOC10537215 are a shared genetic variant of schizophrenia and bipolar disorder in Han Chinese women.

LncRNA MIAT can regulate the proliferation, apoptosis, and osteogenic differentiation of bone marrow-derived mesenchymal stem cells by targeting miR-150-5p

Osteoporosis (OP) is a systemic bone metabolic disease with complicated pathogenesis and is difficult to cure clinically. The regulatory mechanisms of OP are needed to be further investigated. In the present study, we focused on the role of myocardial infarction-associated transcript (MIAT) in OP development and examined the underlying mechanism. The serum expression levels of MIAT in samples from patients with OP and healthy controls were compared using quantitative reverse transcription-PCR (qRT-PCR). The dual-luciferase reporter assay was used to confirm the relationship between MIAT and its potential target microRNA, i.e., miR-150-5p. Moreover, bone marrow-derived mesenchymal stem cells (BMSCs) were cultured and transfected with MIAT shRNA, with or without miR-150-5p inhibitor. EdU staining and colony formation analysis were performed to determine the proliferation ability of these cells. Furthermore, the TUNEL assay and flow cytometry were used to assess BMSC apoptosis. Finally, RT-PCR and Western blot assays were employed to assess the expression of osteogenic differentiation biomarkers. Compared with controls, the expression of MIAT was significantly increased, whereas that of miR-150-5p was markedly decreased in patients with OP. MIAT and miR-150-5p expression levels exhibited a strong negative correlation. Furthermore, osteogenic differentiation indicators were suppressed in serum of OP patients. MIAT was downregulated, and miR-150-5p was upregulated in induced to osteogenic differentiation BMSCs. Furthermore, downregulation of MIAT dramatically promoted osteogenic differentiation, increased proliferation, and inhibited apoptosis in BMSCs; miR-150-5p inhibitor abrogated the effects of MIAT. In conclusion, lncRNA MIAT can regulate the proliferation, apoptosis, and osteogenic differentiation of BMSCs.

Involvement of the long intergenic non-coding RNA LINC00461 in schizophrenia

OBJECTIVE

LINC00461 is a highly conserved intergenic non-protein coding RNA that was implicated in schizophrenia at the genome-wide level. We aim to explore potential mechanisms underlying the involvement of LINC00461 in schizophrenia.

METHODS

We performed a meta-analysis to investigate the association of LINC00461 rs410216 with schizophrenia, and evaluate the effects of the rs410216 on hippocampal volume and function using the functional magnetic resonance imaging (fMRI) analysis. We utilized the GTEx dataset to profile the expression distribution of LINC00461 across different brain regions, and to investigate the potential impact of the risk SNPs on the expression of LINC00461 and other nearby genes. We compared blood expression levels of LINC00461 between schizophrenia patients and controls.

RESULTS

Here we show that single-nucleotide polymorphisms (SNPs) located in regulatory elements spanning the LINC00461 region are significantly associated with schizophrenia (index SNP rs410216, P_meta = 1.43E-05); subjects carrying the risk allele of rs410216 showed decreased hippocampal volume. However, no significant association of the rs410216 variant with hippocampal activation was observed. Moreover, the expression level of LINC00461 mRNA was significantly lower in first-onset schizophrenia patients, and the risk allele also predicts a lower transcriptional level of LINC00461 in the hippocampus.

CONCLUSION

Together, these convergent lines of evidence implicate inadequate LINC00461 expression in the hippocampus in the development of schizophrenia, providing novel insight into the genetic architecture and biological etiology of schizophrenia.

Curcumin improves atherosclerosis by inhibiting the epigenetic repression of lncRNA MIAT to miR-124

Objectives: Atherosclerosis is a dominant cardiovascular disease. Curcumin has protective effect on atherosclerosis. However, the mechanisms remain to be explored. Methods: Atherosclerosis was induced by feeding mice with high-fat diet (HFD) and ox-low-density lipoprotein (LDL)-induced human umbilical vein endothelial cells (HUVECs) were structured. Oil Red O staining was used to evaluate the plaques in the artery. Quantitative real-time PCR (qRT-PCR) was conducted to detect the level of myocardial infarction associated transcript (MIAT), miR-124, and enhancer of zeste homolog 2 (EZH2). We performed western blotting and enzyme linked immunosorbent assay to examine the expression of EZH2 and cytokines including IL-1β, TNFα, IL-6, and IL-8, respectively. RNA immunoprecipitation and chromatin immunoprecipitation (ChIP) were used to validate the interaction between myocardial infarction associated transcript and EZH2. Flow cytometry and CCK-8 assay were used to examine cell apoptosis and proliferation, respectively. Results: Curcumin suppressed inflammation in atherosclerosis mouse model and ox-LDL-induced cell model. MIAT overexpression and miR-124 inhibition relieved the anti-inflammation effect of curcumin in ox-LDL-induced cell. MIAT regulated miR-124 by interacting with EZH2. Curcumin relieved ox-LDL-induced cell inflammation via regulating MIAT/miR-124 pathway. Conclusion: MIAT/miR-124 axis mediated the effect of curcumin on atherosclerosis and altered cell apoptosis and proliferation, both in vivo and in vitro. These data further support the application of curcumin in control of atherosclerosis advancement.

The emerging role of long non-coding RNAs in schizophrenia

Schizophrenia (SZ) is a severe psychiatric disorder which is contributed by both genetic and environmental factors. However, at present, its specific pathogenesis is still not very clear, and there is a lack of objective and reliable biomarkers. Accumulating evidence indicates that long non-coding RNAs (lncRNAs) are involved in the pathophysiology of several psychiatric disorders, including SZ, and hold promise as potential biomarkers and therapeutic targets for psychiatric disorders. In this review, we summarize and discuss the role of lncRNAs in the pathogenesis of SZ and their potential value as biomarkers and therapeutic targets.

LncRNA-MIAT promotes thyroid cancer progression and function as ceRNA to target EZH2 by sponging miR-150-5p

While long noncoding RNAs (lncRNAs) have been reported to play an important role in human cancer types, they remain poorly understood in papillary thyroid carcinoma (PTC). The aim of this study was to use genome-wide expression profiling to identify lncRNAs acting as competing endogenous RNAs (ceRNAs) in PTC. We constructed a ceRNA network based on our lncRNA microarray data and validated the correlation between myocardial infarction-associated transcript lncRNA (MIAT), miRNA-150-5p, and EZH2 in vitro and in vivo. We found 15 lncRNAs, 28 miRNAs, and hundreds of mRNAs involved in this ceRNA network. Splendid positive correlations were found between the MIAT and EZH2 expression in types of cancer in TCGA data. Besides, significant differences in MIAT/EZH2 expression were found among various clinicopathological features. Gain- and loss-of-function experiments revealed that MIAT inhibited cell proliferation and migration in vitro. Moreover, EZH2 was identified as a direct downstream target of miR-150-5p in PTC cells. Restoration of EZH2 expression partially abolished the biological effects of miR-150-5p. Furthermore, overexpression of MIAT was inversely correlated with miR-150-5p expression. Knockdown of MIAT produced significant behavioral alter maybe partly due to the function of the MIAT-150-5p-EZH2 network. Our findings suggest MIAT may inhibit EZH2 expression and promote PTC cell invasion via the miR-150/EZH2 pathway. Therefore, MIAT may serve as a valuable prognostic biomarker and therapeutic target for PTC.

Regulatory role of long non coding RNAs (lncRNAs) in neurological disorders: From novel biomarkers to promising therapeutic strategies

Long non coding RNAs (lncRNAs) are non-protein or low-protein coding transcripts that contain more than 200 nucleotides. They representing a large share of the cell's transcriptional output, demonstrate functional attributes viz. tissue-specific expression, determination of cell fate, controlled expression, RNA processing and editing, dosage compensation, genomic imprinting, conserved evolutionary traits etc. These long non coding variants are well associated with pathogenicity of various diseases including the neurological disorders like Alzheimer's disease, schizophrenia, Huntington's disease, Parkinson's disease etc. Neurological disorders are widespread and there knowing the underlying mechanisms become crucial. The lncRNAs take part in the pathogenesis by a plethora of mechanisms like decoy, scaffold, mi-RNA sequestrator, histone modifiers and in transcriptional interference. Detailed knowledge of the role of lncRNAs can help to use them further as novel biomarkers for therapeutic aspects. Here, in this review we discuss regulation and functional roles of lncRNAs in eight neurological diseases and psychiatric disorders, and the mechanisms by which they act. With these, we try to establish their roles as potential markers and viable diagnostic tools in these disorders.

Neuroepigenetics of psychiatric disorders: Focus on lncRNA

Understanding the pathology of psychiatric disorders is challenging due to their complexity and multifactorial origin. However, development of high-throughput technologies has allowed for better insight into their molecular signatures. Advancement of sequencing methodologies have made it possible to study not only the protein-coding but also the noncoding genome. It is now clear that besides the genetic component, different epigenetic mechanisms play major roles in the onset and development of psychiatric disorders. Among them, examining the role of long noncoding RNAs (lncRNAs) is a relatively new field. Here, we present an overview of what is currently known about the involvement of lncRNAs in schizophrenia, major depressive and bipolar disorders, as well as suicide. The diagnosis of psychiatric disorders mainly relies on clinical evaluation without using measurable biomarkers. In this regard, lncRNA may open new opportunities for development of molecular tests. However, so far only a small set of known lncRNAs have been characterized at molecular level, which means they have a long way to go before clinical implementation. Understanding how changes in lncRNAs affect the appearance and development of psychiatric disorders may lead to a more classified and objective diagnostic system, but also open up new therapeutic targets for these patients.

Brain Long Noncoding RNAs: Multitask Regulators of Neuronal Differentiation and Function

The extraordinary cellular diversity and the complex connections established within different cells types render the nervous system of vertebrates one of the most sophisticated tissues found in living organisms. Such complexity is ensured by numerous regulatory mechanisms that provide tight spatiotemporal control, robustness and reliability. While the unusual abundance of long noncoding RNAs (lncRNAs) in nervous tissues was traditionally puzzling, it is becoming clear that these molecules have genuine regulatory functions in the brain and they are essential for neuronal physiology. The canonical view of RNA as predominantly a 'coding molecule' has been largely surpassed, together with the conception that lncRNAs only represent 'waste material' produced by cells as a side effect of pervasive transcription. Here we review a growing body of evidence showing that lncRNAs play key roles in several regulatory mechanisms of neurons and other brain cells. In particular, neuronal lncRNAs are crucial for orchestrating neurogenesis, for tuning neuronal differentiation and for the exact calibration of neuronal excitability. Moreover, their diversity and the association to neurodegenerative diseases render them particularly interesting as putative biomarkers for brain disease. Overall, we foresee that in the future a more systematic scrutiny of lncRNA functions will be instrumental for an exhaustive understanding of neuronal pathophysiology.

A Review on the Expression Pattern of Non-coding RNAs in Patients With Schizophrenia: With a Special Focus on Peripheral Blood as a Source of Expression Analysis

Schizophrenia is a destructive neuropsychiatric disease with a median prevalence of 4.0 per 1,000 during the whole life. Genome-wide association studies have shown the role of copy number variants (generally deletions) and certain alleles of common single nucleotide polymorphisms in the pathogenesis of schizophrenia. This disorder predominantly follows the polygenic inheritance model. Schizophrenia has also been linked with various alterations in the transcript and protein content of the brain tissue. Recent studies indicate that alterations in non-coding RNAs (ncRNAs) signature underlie a proportion of this dysregulation. High throughput microarray investigations have demonstrated momentous alterations in the expression of long non-coding RNAs (lncRNA) and microRNAs (miRNAs) in the circulation or post-mortem brain tissues of patients with schizophrenia compared with control samples. While Gomafu, PINT, GAS5, TCONS_l2_00021339, IFNG-AS1, FAS-AS1, PVT1, and TUG1 are among down-regulated lncRNAs in schizophrenia, MEG3, THRIL, HOXA-AS2, Linc-ROR, SPRY4-IT1, UCA1, and MALAT1 have been up-regulated in these patients. Moreover, several miRNAs, such as miR-30e, miR-130b, hsa-miR-130b, miR-193a-3p, hsa-miR-193a-3p, hsa-miR-181b, hsa-miR-34a, hsa-miR-346, and hsa-miR-7 have been shown to be dysregulated in blood or brain samples of patients with schizophrenia. Dysregulation of these transcripts in schizophrenia not only provides insight into the pathogenic processes of this disorder, it also suggests these transcripts could serve as diagnostic markers for schizophrenia. In the present paper, we explore the changes in the expression of miRNAs and lncRNAs in patients with schizophrenia.

Lyme Neuroborreliosis: Mechanisms of B. burgdorferi Infection of the Nervous System

Lyme borreliosis is the most prevalent tick-borne disease in the United States, infecting ~476,000 people annually. Borrelia spp. spirochetal bacteria are the causative agents of Lyme disease in humans and are transmitted by Ixodes spp ticks. Clinical manifestations vary depending on which Borrelia genospecies infects the patient and may be a consequence of distinct organotropism between species. In the US, B. burgdorferi sensu stricto is the most commonly reported genospecies and infection can manifest as mild to severe symptoms. Different genotypes of B. burgdorferi sensu stricto may be responsible for causing varying degrees of clinical manifestations. While the majority of Lyme borreliae-infected patients fully recover with antibiotic treatment, approximately 15% of infected individuals experience long-term neurological and psychological symptoms that are unresponsive to antibiotics. Currently, long-term antibiotic treatment remains the only FDA-approved option for those suffering from these chronic effects. Here, we discuss the current knowledge pertaining to B. burgdorferi sensu stricto infection in the central nervous system (CNS), termed Lyme neuroborreliosis (LNB), within North America and specifically the United States. We explore the molecular mechanisms of spirochete entry into the brain and the role B. burgdorferi sensu stricto genotypes play in CNS infectivity. Understanding infectivity can provide therapeutic targets for LNB treatment and offer public health understanding of the B. burgdorferi sensu stricto genotypes that cause long-lasting symptoms.

Promoter polymorphisms in the lncRNA-MIAT gene associated with acute myocardial infarction in Chinese Han population: a case-control study

BACKGROUND

Coronary atherosclerotic disease (CAD) is one of the greatest causes of death and disability around the world, and has emerged as a major public health problem. Acute myocardial infarction (AMI) is the most serious type of CAD. Myocardial infarction (MI) association transcript (MIAT) has demonstrated that it plays an important role in AMI.

PURPOSE

To investigate the association between MIAT promoter polymorphisms and AMI in Chinese Han population.

METHODS

A total of 212 AMI patients and 218 healthy controls were recruited. The long non-coding RNA (lncRNA)-MIAT promoter polymorphisms (single nucleotide polymorphisms (SNPs)) were obtained using polymerase chain reaction (PCR) and sequencing techniques. Chi-square test was used to analyze the allele and genotype frequencies of each SNP in two groups. Logistic regression analysis was used to analyze the association of each SNP with AMI. Linkage disequilibrium (LD) and haplotype analysis were performed using SHEsis software. A JASPAR database search predicts transcription factors transition of linked polymorphism in MIAT promoter.

RESULTS

Ten SNPs were found, including rs56371714, rs55892869, rs151057042, rs2157598, rs150465374, rs5761664, rs8142890, rs5752375, rs9608515 and rs1055293700, whereas rs1055293700 was found only in the control group. Single and logistic regression analysis showed that there was a significant correlation between rs5752375 and rs9608515 polymorphisms and AMI, while other sites had no relationship with AMI. These MI association polymorphisms may change the binding sites with transcription factor.

CONCLUSIONS

The polymorphisms of lncRNA-MIAT promoter rs5752375 and rs9608515 were significantly associated with AMI in Chinese Han population. This result would be of clinical importance for the early diagnosis of AMI.

Non-Syndromic Intellectual Disability and Its Pathways: A Long Noncoding RNA Perspective

Non-syndromic intellectual disability (NS-ID or idiopathic) is a complex neurodevelopmental disorder that represents a global health issue. Although many efforts have been made to characterize it and distinguish it from syndromic intellectual disability (S-ID), the highly heterogeneous aspect of this disorder makes it difficult to understand its etiology. Long noncoding RNAs (lncRNAs) comprise a large group of transcripts that can act through various mechanisms and be involved in important neurodevelopmental processes. In this sense, comprehending the roles they play in this intricate context is a valuable way of getting new insights about how NS-ID can arise and develop. In this review, we attempt to bring together knowledge available in the literature about lncRNAs involved with molecular and cellular pathways already described in intellectual disability and neural function, to better understand their relevance in NS-ID and the regulatory complexity of this disorder.

Epigenomic Dysregulation in Schizophrenia: In Search of Disease Etiology and Biomarkers

Schizophrenia is a severe psychiatric disorder with a complex array of signs and symptoms that causes very significant disability in young people. While schizophrenia has a strong genetic component, with heritability around 80%, there is also a very significant range of environmental exposures and stressors that have been implicated in disease development and neuropathology, such as maternal immune infection, obstetric complications, childhood trauma and cannabis exposure. It is postulated that epigenetic factors, as well as regulatory non-coding RNAs, mediate the effects of these environmental stressors. In this review, we explore the most well-known epigenetic marks, including DNA methylation and histone modification, along with emerging RNA mediators of epigenomic state, including miRNAs and lncRNAs, and discuss their collective potential for involvement in the pathophysiology of schizophrenia implicated through the postmortem analysis of brain tissue. Given that peripheral tissues, such as blood, saliva, and olfactory epithelium have the same genetic composition and are exposed to many of the same environmental exposures, we also examine some studies supporting the application of peripheral tissues for epigenomic biomarker discovery in schizophrenia. Finally, we provide some perspective on how these biomarkers may be utilized to capture a signature of past events that informs future treatment.

Significance of Single-Nucleotide Variants in Long Intergenic Non-protein Coding RNAs

Single-nucleotide variants (SNVs) are the most common genetic variants and universally present in the human genome. Genome-wide association studies (GWASs) have identified a great number of disease or trait-associated variants, many of which are located in non-coding regions. Long intergenic non-protein coding RNAs (lincRNAs) are the major subtype of long non-coding RNAs; lincRNAs play crucial roles in various disorders and cellular models via multiple mechanisms. With rapid growth in the number of the identified lincRNAs and genetic variants, there is great demand for an investigation of SNVs in lincRNAs. Hence, in this article, we mainly summarize the significant role of SNVs within human lincRNA regions. Some pivotal variants may serve as risk factors for the development of various disorders, especially cancer. They may also act as important regulatory signatures involved in the modulation of lincRNAs in a tissue- or disorder-specific manner. An increasing number of researches indicate that lincRNA variants would potentially provide additional options for genetic testing and disease risk assessment in the personalized medicine era.

Emerging Roles of Estrogen-Regulated Enhancer and Long Non-Coding RNAs

Genome-wide RNA sequencing has shown that only a small fraction of the human genome is transcribed into protein-coding mRNAs. While once thought to be “junk” DNA, recent findings indicate that the rest of the genome encodes many types of non-coding RNA molecules with a myriad of functions still being determined. Among the non-coding RNAs, long non-coding RNAs (lncRNA) and enhancer RNAs (eRNA) are found to be most copious. While their exact biological functions and mechanisms of action are currently unknown, technologies such as next-generation RNA sequencing (RNA-seq) and global nuclear run-on sequencing (GRO-seq) have begun deciphering their expression patterns and biological significance. In addition to their identification, it has been shown that the expression of long non-coding RNAs and enhancer RNAs can vary due to spatial, temporal, developmental, or hormonal variations. In this review, we explore newly reported information on estrogen-regulated eRNAs and lncRNAs and their associated biological functions to help outline their markedly prominent roles in estrogen-dependent signaling.

Rs1894720 polymorphism is associated with the risk of age-related cataract by regulating the proliferation of epithelial cells in the lens via the signalling pathway of MIAT/miR-26b/BCL2L2

INTRODUCTION

Cataracts caused by old age are one of the most frequent causes for blindness and poor vision worldwide. In this study, we aimed to clarify the possible role of rs1894720 polymorphism in the pathogenesis of age-related cataract.

MATERIAL AND METHODS

Rs1894720 polymorphism genotype was detected by TaqMan. Bioinformatics analysis, luciferase assay, real-time PCR, western blot, and protein density analysis were conducted to establish the correlations between MIAT and miR-26b as well as between BCL2L2 and miR-26b. Flow cytometry and MTT assay were also performed to observe the effect of MIAT/miR-26b/BCL2L2 signalling pathway on the status of cell apoptosis and viability.

RESULTS

MIAT functioned as an endogenous competing RNA to sponge miR-26b. In addition, BCL2L2 was identified as a target of miR-26b. Therefore, the expression of miR-26b was obviously suppressed by MIAT or anti-miR-26b, while the mRNA and protein expression of BCL2L2 was up-regulated in the presence of MIAT or anti-miR-26b. Moreover, the positive effect of MIAT on BCL2L2 expression was exerted via inhibition of the expression of miR-26b. In addition, the cells transfected with MIAT or anti-miR-26b showed suppressed expression of caspase-3 and reduced apoptosis index but higher cell viability, indicating that MIAT could suppress cell apoptosis via inhibition of miR-26b expression. Furthermore, the subjects carrying the GT and TT genotypes of single-nucleotide polymorphism (SNP) rs1894720 were associated with a higher risk of age-related cataracts, as indicated by their odds ratio (OR) and p-values.

CONCLUSIONS

Rs1894720 SNP could down-regulate the expression of MIAT, thus leading to reduced BCL2L2 expression and enhanced epithelial cell apoptosis in the lens, eventually increasing the incidence of age-related cataract.

Huo Xue Tong Luo capsule ameliorates osteonecrosis of femoral head through inhibiting lncRNA-Miat

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine has a long history of treating various bone diseases including osteoporosis and osteonecrosis etc. In clinical treatment, Huo Xue Tong Luo capsule (HXTL capsule) containing Peach kernel, Safflower carthamus, Angelica sinensis, Ligusticum wallichii etc, is one of the mostly used prescriptions for treating osteonecrosis of the femoral head (ONFH) with promising effects.

OBJECTIVES

This study aims to identify the underlying molecular mechanism of how HXTL capsule exerts its function to ameliorate ONFH.

MATERIALS AND METHODS

All femoral bone tissues were collected during surgeries. Rat bone marrow mesenchymal stem cells (rMSCs) were used. Quantitative real time PCR was used to check the relative expression levels of genes. ChIP assay was performed to evaluate the binding of H3K4me3 and H3K27me3 in Miat promoter.

RESULTS

We showed that HXTL capsule promoted osteogenesis in rat MSCs as demonstrated by quantitative real time PCR and Alizarin Red S staining. Then we found silencing the endogenous lncRNA-Miat could promote osteogenesis of rMSCs. In addition, the ChIP assay showed that HXTL capsule significantly increased occupancy of H3K27me3 and decreased H3K4me3 in promoter regions of Miat, meaning HXTL capsule inhibited Miat expression through histone modifications. At last, by examining the femoral heads samples obtained from patients with ONFH during total hip arthroplasty surgery, we found the RNA level of hMiat in necrotic tissue was much higher than that of normal tissue.

CONCLUSIONS

Taken together, our study shows that lncRNA-Miat might play an important role in pathogenesis of ONFH, and HXTL capsule can promote osteogenesis to ameliorate ONFH through inhibiting the transcriptional expression of Miat, at least partially.

SSS-test: a novel test for detecting positive selection on RNA secondary structure

BACKGROUND

Long non-coding RNAs (lncRNAs) play an important role in regulating gene expression and are thus important for determining phenotypes. Most attempts to measure selection in lncRNAs have focused on the primary sequence. The majority of small RNAs and at least some parts of lncRNAs must fold into specific structures to perform their biological function. Comprehensive assessments of selection acting on RNAs therefore must also encompass structure. Selection pressures acting on the structure of non-coding genes can be detected within multiple sequence alignments. Approaches of this type, however, have so far focused on negative selection. Thus, a computational method for identifying ncRNAs under positive selection is needed.

RESULTS

We introduce the SSS-test (test for Selection on Secondary Structure) to identify positive selection and thus adaptive evolution. Benchmarks with biological as well as synthetic controls yield coherent signals for both negative and positive selection, demonstrating the functionality of the test. A survey of a lncRNA collection comprising 15,443 families resulted in 110 candidates that appear to be under positive selection in human. In 26 lncRNAs that have been associated with psychiatric disorders we identified local structures that have signs of positive selection in the human lineage.

CONCLUSIONS

It is feasible to assay positive selection acting on RNA secondary structures on a genome-wide scale. The detection of human-specific positive selection in lncRNAs associated with cognitive disorder provides a set of candidate genes for further experimental testing and may provide insights into the evolution of cognitive abilities in humans.

AVAILABILITY

The SSS-test and related software is available at: https://github.com/waltercostamb/SSS-test . The databases used in this work are available at: http://www.bioinf.uni-leipzig.de/Software/SSS-test/ .

LncRNA MIAT overexpression reduced neuron apoptosis in a neonatal rat model of hypoxic-ischemic injury through miR-211/GDNF

OBJECTIVE

To investigate the underlying mechanism of lncRNA myocardial infarction-associated transcript (MIAT) in hypoxic-ischemic (HI)-induced neonatal cerebral palsy.

MATERIALS AND METHODS

Neonatal rat model of HI injury was established to detect the motor function. LncRNA MIAT, miR-211, glial cell line-derived neurotrophic factor (GDNF) and caspase-3 expressions were measured by qRT-PCR or western blot. The apoptosis of Neuro2A cells was detected by flow cytometry. RNA immunoprecipitation (RIP) and RNA pull-down assays were performed to confirm the interaction between MIAT and miR-211.

RESULTS

Compared with control group, lncRNA MIAT and GDNF were downregulated in striatal tissues of neonatal rats in HI group and oxygen glucose deprivation (OGD)-induced ischemic injury of Neuro2A cells, whereas miR-211 was up-regulated in striatal tissues of HI group and OGD-induced ischemic injury of Neuro2A cells. LncRNA MIAT interacted with miR-211, and lncRNA MIAT overexpression reduced neuron apoptosis through miR-211. Besides, GDNF expression was positively regulated by lncRNA MIAT and negatively regulated by miR-211 in Neuro2A cells. In vivo experiment proved MIAT promoted motor function and relieved HI injury.

CONCLUSION

MIAT overexpression reduced apoptosis of Neuro2A cells through miR-211/GDNF, which relieved HI injury of neonatal rats.

Rs1894720 polymorphism in MIAT increased susceptibility to age-related hearing loss by modulating the activation of miR-29b/SIRT1/PGC-1α signaling

BACKGROUND

MIAT may be implicated in the pathogenesis of age-related hearing loss (AHL). This study aimed to clarify the effect of a MIAT signaling pathway on the risk of AHL.

METHODS

Terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, auditory brainstem response (ABR) and quantitative hair cell counts were used to compare the hearing functions in different groups of mice. 5,5,6,6-Tetrachloro-1,1,3,3-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) dye method was used to establish the potential association between mitochondrial dysfunction and aging. Real-time polymerase chain reaction, Western blot analysis, computational analysis, and luciferase assay were conducted to establish a myocardial infarction associated transcript (MIAT) signaling pathway, whose role in the pathogenesis of AHL was further validated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay and flow cytometry.

RESULTS

Aged C57BL/6 mice were associated with a more severe level of hair cell loss, while exhibiting a higher ABR threshold at various frequencies as well as a lower percentage of inner/outer hair cells. A reduced mitochondrial membrane potential in the cochleae of aged C57BL/6 mice indicated the presence of mitochondrial dysfunction in these mice. Relative expression of MIAT, Sirtuin1 (SIRT1), and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) was downregulated in aged mice, with microRNA-29b (miR-29b) being highly expressed. Also, MIAT binds to miR-29b, an inhibitor of SIRT1 expression. The regulatory relationship among MIAT, miR-29b, and SIRT1 was further validated by comparing the differentiated expression of these factors in cells treated with phosphate-buffered saline + H₂ O_2, a negative control + H₂ O_2, MIAT + H₂ O₂ , or H₂ O₂  + anti-miR-29b.

CONCLUSION

MIAT could elevate the expression of SIRT1/PGC-1α via downregulating miR-29b. And the downregulated SIRT/PGC-1α increased the incidence of AHL via promoting the apoptosis of cochlear hair cells.

Coregulatory long non-coding RNA and protein-coding genes in serum starved cells

Serum starvation is widely used in cell biology to trigger cell cycle arrest, apoptosis, autophagy, and metabolic adaptations. Serum starvation-related molecular events have been well characterized at protein level but not at transcript level: how long non-coding RNAs contribute to the regulation of protein-coding genes is largely unknown. Here, we captured the lncRNA transcriptome in serum starved mouse embryonic fibroblasts and identified three main modes of action: cis-acting/coregulatory, trans-acting, and "miRNA-carrier". Whole-genome and individual gene level analyses support that our annotation provides an important platform for understanding lncRNA/protein-coding gene coregulatory mechanisms in serum starvation.

WITHDRAWN: Single nucleotide polymorphism, a putative driver for the role of long intergeneric non-coding RNA

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Relationship between schizophrenia and changes in the expression of the long non-coding RNAs Meg3, Miat, Neat1 and Neat2

Schizophrenia (SZ) is a complex disease caused by multiple factors. The development of the disease is mediated by a number of neural growth and development factors, suggesting that extensive changes in nerve structure and abnormal expression of genes in some important signalling pathways occur. Based on accumulating evidence, long non-coding RNAs (lncRNAs) play a crucial role in regulating neural diseases, including SZ. In the current study, we used mouse models of methamphetamine (METH) - and MK801-induced SZ to investigate changes in the expression of four lncRNAs (Meg3, Miat, Neat1 and Neat2) in the prefrontal cortex (PFC). Miat and Neat2 expression was significantly decreased in the PFC of the SZ model mice, regardless of whether the disease was induced by MK801 or METH. We further measured the levels of these lncRNAs in the peripheral blood (PB) collected from treated and untreated patients with SZ and from healthy controls. Neat1 and Neat2 levels were significantly decreased in the PB of untreated patients with SZ, but the trends in the expression of these lncRNAs nearly reached a normal level in treated patients with SZ. In conclusion, Neat2 and Miat may function as important regulators of SZ. Our findings provide important clues for new targets of lncRNAs that are involved in SZ.

Long noncoding RNA MIAT regulates apoptosis and the apoptotic response to chemotherapeutic agents in breast cancer cell lines

The long noncoding RNA myocardial infarction associated transcript (MIAT) is involved in a number of diseases, including myocardial infarction and diabetic retinopathy. Emerging evidence suggests that MIAT expression levels are increased in different type of cancers, including breast cancer. In the present study, we further evaluated the role of MIAT in breast cancer and investigated the consequences of its silencing on breast cancer response to chemotherapeutic agents. Expression levels of MIAT mRNA in breast cancer were determined using TissueScan™ Breast Cancer cDNA Arrays. Breast cancer cell lines were transfected with MIAT specific siRNAs, with silencing confirmed using RT-qPCR and the effects on breast cancer cell survival and response to different apoptotic stimuli determined. MIAT transcript levels were significantly elevated in breast cancer samples. Such increase was specific to the early stages of the disease, ER, PR +ve, HER –ve, and triple negative breast cancer samples. Silencing of MIAT induced growth arrest and increased basal apoptosis. Reduced levels of MIAT augmented the apoptotic response of breast cancer cells to a wide range of apoptotic stimuli. Our results also showed that MIAT down-regulation was associated with a decrease in OCT4 mRNA, suggesting the existence of a MIAT/OCT4 regulatory loop, similar to that observed in malignant mature B cells. Taken together with the recent demonstration of oncogene characteristics, our observations suggest that MIAT plays an important role in breast tumorigenesis. Strategies to decrease MIAT expression levels may improve sensitivity to therapy in breast cancer by enhancing the apoptotic responses to conventional chemotherapies.

Long noncoding RNA myocardial infarction‑associated transcript is associated with the microRNA‑150‑5p/P300 pathway in cardiac hypertrophy

In numerous diseases, abnormal expression of myocardial infarction-associated transcript (MIAT) has been reported to be involved in cell proliferation, apoptosis and migration. However, whether this long non-coding RNA MIAT has a regulatory effect on heart hypertrophy requires further investigation. To this end, the present study evaluated MIAT in hypertrophic cardiomyocytes in vitro and in vivo. Neonatal rat ventricular myocytes (NRVMs) were induced by isoproterenol (ISO) to create a cell hypertrophy model, and mice were intraperitoneally injected with ISO to establish an animal model. Echocardiography, immunofluorescence staining, western blot analysis, RNA isolation and reverse transcription-polymerase chain reaction were applied to test the involvement of MIAT in cardiac hypertrophy. The results revealed that MIAT was upregulated under ISO stimulation at the mRNA level both in vivo and in vitro. Silencing of MIAT resulted in decreased expression levels of atrial natriuretic peptide and brain natriuretic peptide in ISO-treated NRVM cardiomyocytes, confirming the connection between MIAT and hypertrophy. Furthermore, MIAT small interfering RNA significantly increased microRNA (miR)-150 and decreased P300 expression in NRVMs. In conclusion, the MIAT/miR-150-5p axis targets P300 as a positive regulator of cardiomyocyte hypertrophy.

The lncRNA myocardial infarction associated transcript-centric competing endogenous RNA network in non-small-cell lung cancer

Background

The leading cause of death for cancer is lung cancer, of which the majority subtype is non-small cell lung cancer (NSCLC). Recent studies have shown long non-coding RNAs are transcribed and contribute to cancer. Previous study has shown that a few single nucleotide polymorphisms (SNPs) in myocardial infarction associated transcript (MIAT) were associated with some diseases or function as competing endogenous RNA (ceRNA) in some cancer.

Patients and methods

We performed bioinformatic methods for analyzing RNA-seq and miRNA-seq data of NSCLC from The Cancer Genome Atlas database. 1352 NSCLC patients and 1320 cancer-free controls for genotyping, and dual luciferase reporter assay, real-time PCR are performed in A549 and H1975 lung cancer cell lines. Results are analyzed by SPSS v16.0.

Results

In the present study, we focus on the role of over-expression MIAT in NSCLC. We confirmed that rs1061451 T>C (allele odds ratio = 0.22; P < 0.01) was associated with NSCLC. Furthermore, we constructed MIAT-centric ceRNA network, and three mRNAs (MYO1B, SGK1 and WNT9A) was identified as targets by MIAT via miR-133a-5p.

Conclusion

C-containing genotypes of MIAT rs1061451 were protective factor of NSCLC, and MIAT, which may act as ceRNA via miR-133a-5p, modulated MYO1B, SGK1 and WNT9A expression level.

Long Non-Coding RNAs in Multifactorial Diseases: Another Layer of Complexity

Multifactorial diseases such as cancer, cardiovascular conditions and neurological, immunological and metabolic disorders are a group of diseases caused by the combination of genetic and environmental factors. High-throughput RNA sequencing (RNA-seq) technologies have revealed that less than 2% of the genome corresponds to protein-coding genes, although most of the human genome is transcribed. The other transcripts include a large variety of non-coding RNAs (ncRNAs), and the continuous generation of RNA-seq data shows that ncRNAs are strongly deregulated and may be important players in pathological processes. A specific class of ncRNAs, the long non-coding RNAs (lncRNAs), has been intensively studied in human diseases. For clinical purposes, lncRNAs may have advantages mainly because of their specificity and differential expression patterns, as well as their ideal qualities for diagnosis and therapeutics. Multifactorial diseases are the major cause of death worldwide and many aspects of their development are not fully understood. Recent data about lncRNAs has improved our knowledge and helped risk assessment and prognosis of these pathologies. This review summarizes the involvement of some lncRNAs in the most common multifactorial diseases, with a focus on those with published functional data.

MIAT lncRNA is overexpressed in breast cancer and its inhibition triggers senescence and G1 arrest in MCF7 cell line

Long non-coding RNAs are known as key regulators in the progression and metastasis of breast cancer. MIAT originally has been considered as an lncRNA to be associated with a susceptibility to myocardial infarction. Here, we have detected the expression of MIAT in different cancer cells and a series of breast tumor tissue. MIAT expression was much higher in high-grade tumors compared to low-grade ones. Unlike P53 positive tumors, MIAT expression was upregulated in ER, PR, Her2 positive tumor tissues. Knockdown MIAT suppressed breast cancer cell proliferation and caused G1 arrest in cell cycle. Furthermore, downregulation of MIAT promoted apoptosis and significantly decreased migration of breast cancer cells. An increase in the expression of mir-302, mir-150, and a decrease in the expression of mir-29c were detected following MIAT silencing. More importantly, knockdown MIAT significantly elevated the expression of p16^Ink4A and Cox2, which commitment cellular senescence in breast cancer cells. Altogether, our results suggest that MIAT involved in breast cancer progression and could be candidate as a novel tumor marker for diagnosis and treatment of breast cancer.

Non-Coding RNA as Novel Players in the Pathophysiology of Schizophrenia

Schizophrenia is associated with diverse changes in the brain's transcriptome and proteome. Underlying these changes is the complex dysregulation of gene expression and protein production that varies both spatially across brain regions and temporally with the progression of the illness. The growing body of literature showing changes in non-coding RNA in individuals with schizophrenia offers new insights into the mechanisms causing this dysregulation. A large number of studies have reported that the expression of microRNA (miRNA) is altered in the brains of individuals with schizophrenia. This evidence is complemented by findings that single nucleotide polymorphisms (SNPs) in miRNA host gene sequences can confer an increased risk of developing the disorder. Additionally, recent evidence suggests the expression of other non-coding RNAs, such as small nucleolar RNA and long non-coding RNA, may also be affected in schizophrenia. Understanding how these changes in non-coding RNAs contribute to the development and progression of schizophrenia offers potential avenues for the better treatment and diagnosis of the disorder. This review will focus on the evidence supporting the involvement of non-coding RNA in schizophrenia and its therapeutic potential.

Long non-coding RNA MIAT in development and disease: a new player in an old game

Background

Long non-coding RNAs (lncRNAs), which are a portion of non-protein-coding RNAs (ncRNAs), have manifested a paramount role in the pathophysiology of human diseases, particularly in pathogenesis and progression of disease.

Main body of the abstract

Myocardial infarction associated transcript (MIAT), which was recently found to demonstrate aberrant expression in various diseases, such as myocardial infarction, schizophrenia, ischemic stroke, diabetic complications, age-related cataract and cancers, is a novel disease-related lncRNA. This work summarize current evidence regarding the biological functions and underlying mechanisms of lncRNA MIAT during disease development.

Short conclusion

LncRNA MIAT likely represents a feasible cancer biomarker or therapeutic target.

Ethical Application of Precision Medicine to Schizophrenia Management

A recent effort has been made to better characterize the genetic architecture of schizophrenia, and apply a precision medicine model to its treatment. In pursuing this approach, it is likely that ethical concerns regarding cost-benefit uncertainties, the duty to inform and confidentiality will arise. Due to the complexity of schizophrenia's genetic profile, research efforts must be weighed against the risk to human subjects and the required consumption of valuable healthcare resources. Genetic risk profiles must be judged in conjunction with actionability and must be fully explained to patients and others potentially affected. However, confidentiality should be of paramount importance due to the presence of a risk-state phenotype, meaning the associated presence of clinically detectable neurocognitive deficiencies in those with elevated schizophrenia risk profiles.

Long noncoding RNA MIAT promotes non-small cell lung cancer proliferation and metastasis through MMP9 activation

Long noncoding RNAs (lncRNAs) play crucial roles in carcinogenesis. Myocardial infarction-associated transcript (MIAT), originally isolated as a candidate gene for myocardial infarction, has been found to act as an oncogene in chronic lymphocytic leukaemias and neuroendocrine prostate cancer (NEPC); however, little is known about its expression pattern, biological function, and underlying mechanism in non-small cell lung cancer (NSCLC). In this study, we observed that MIAT expression was upregulated in NSCLC, and its overexpression was associated with advanced tumor stage. Moreover, MIAT knockdown decreased cell proliferation, migration, invasion, and cell cycle arrested in G1 phase. Mechanistic investigation revealed that MIAT could interact with histone methyltransferase mixed-lineage leukemia (MLL). MIAT silencing impeded the binding of MLL on the matrix metalloproteinase 9 (MMP9) promoter region and epigenetically reduced MMP9 transcriptional activity. Overall, our findings suggest that MIAT expression is associated with NSCLC and may be one of the critical targets in progression and metastasis in NSCLC.

Novel brain expressed RNA identified at the MIR137 schizophrenia-associated locus

Genome-wide association studies (GWAS) have identified a locus on chromosome 1p21.3 to be highly associated with schizophrenia. A microRNA, MIR137, within this locus has been proposed as the gene causally associated with schizophrenia, due to its known role as a regulator of neuronal development and function. However, the involvement of other genes within this region, including DPYD (dihydropyrimidine dehydrogenase), is also plausible. In this communication, we describe a previously uncharacterised, brain-expressed RNA, EU358092, within the schizophrenia-associated region at 1p21.3. As we observed for MIR137, EU358092 expression was modulated in response to psychoactive drug treatment in the human SH-SY5Y neuroblastoma cell line. Bioinformatic analysis of publically available CNS expression data indicates that MIR137 and EU358092 are often co-expressed in vivo. A potential regulatory domain for expression of EU358092 is identified by bioinformatic analysis and its regulatory function is confirmed by reporter gene assays. These data suggest a potentially important role for EU358092 in the aetiology of schizophrenia, either individually or in combination with other genes at this locus.