Emerging roles for ncRNAs in alcohol use disorders

Potential Molecular Mechanisms of Alcohol Use Disorder with Non-Coding RNAs and Gut Microbiota for the Development of Superior Therapeutic Application

Many investigations have evaluated the expression of noncoding RNAs (ncRNAs) as well as their related molecular functions and biological machineries in individuals with alcohol dependence. Alcohol dependence may be one of the most prevailing psychological disorders globally, and its pathogenesis is intricate and inadequately comprehended. There is substantial evidence indicating significant links between multiple genetic factors and the development of alcohol dependence. In particular, the critical roles of ncRNAs have been emphasized in the pathology of mental illnesses, probably including alcohol dependence. In the comprehension of the action of ncRNAs and their machineries of modification, furthermore, they have emerged as therapeutic targets for a variety of psychiatric illnesses, including alcohol dependence. It is worth mentioning that the dysregulated expression of ncRNAs has been regularly detected in individuals with alcohol dependence. An in-depth knowledge of the roles of ncRNAs and m6A modification may be valuable for the development of a novel treatment against alcohol dependence. In general, a more profound understanding of the practical roles of ncRNAs might make important contributions to the precise diagnosis and/or actual management of alcohol dependence. Here, in this review, we mostly focused on up-to-date knowledge regarding alterations and/or modifications in the expression of ncRNAs in individuals with alcohol dependence. Then, we present prospects for future research and therapeutic applications with a novel concept of the engram system.

Mutation of novel ethanol-responsive lncRNA Gm41261 impacts ethanol-related behavioral responses in mice

Chronic alcohol exposure results in widespread dysregulation of gene expression that contributes to the pathogenesis of Alcohol Use Disorder (AUD). Long noncoding RNAs are key regulators of the transcriptome that we hypothesize coordinate alcohol-induced transcriptome dysregulation and contribute to AUD. Based on RNA-Sequencing data of human prefrontal cortex, basolateral amygdala and nucleus accumbens of AUD versus non-AUD brain, the human LINC01265 and its predicted murine homolog Gm41261 (i.e., TX2) were selected for functional interrogation. We tested the hypothesis that TX2 contributes to ethanol drinking and behavioral responses to ethanol. CRISPR/Cas9 mutagenesis was used to create a TX2 mutant mouse line in which 306 base-pairs were deleted from the locus. RNA analysis revealed that an abnormal TX2 transcript was produced at an unchanged level in mutant animals. Behaviorally, mutant mice had reduced ethanol, gaboxadol and zolpidem-induced loss of the righting response and reduced tolerance to ethanol in both sexes. In addition, a male-specific reduction in two-bottle choice every-other-day ethanol drinking was observed. Male TX2 mutants exhibited evidence of enhanced GABA release and altered GABAA receptor subunit composition in neurons of the nucleus accumbens shell. In C57BL6/J mice, TX2 within the cortex was cytoplasmic and largely present in Rbfox3+ neurons and IBA1+ microglia, but not in Olig2+ oligodendrocytes or in the majority of GFAP+ astrocytes. These data support the hypothesis that TX2 mutagenesis and dysregulation impacts ethanol drinking behavior and ethanol-induced behavioral responses in mice, likely through alterations in the GABAergic system.

Functional roles, regulatory mechanisms and theranostics applications of ncRNAs in alcohol use disorder

Alcohol use disorder (AUD) is one of the most prevalent neuropsychological disorders worldwide, and its pathogenesis is convoluted and poorly understood. There is considerable evidence demonstrating significant associations between multiple heritable factors and the onset and progression of AUD. In recent years, a substantial body of research conducted by emerging biotechnologies has increasingly highlighted the crucial roles of noncoding RNAs (ncRNAs) in the pathophysiology of mental diseases. As in-depth understanding of ncRNAs and their mechanisms of action, they have emerged as prospective diagnostic indicators and preclinical therapeutic targets for a variety of psychiatric illness, including AUD. Of note, dysregulated expression of ncRNAs such as circRNAs, lncRNAs and miRNAs was routinely found in AUD individuals, and besides, exogenous regulation of partial ncRNAs has also been shown to be effective in ameliorating alcohol preference and excessive alcohol consumption. However, the exact molecular mechanism still remains elusive. Herein, we systematically summarized current knowledge regarding alterations in the expression of certain ncRNAs as well as their-mediated regulatory mechanisms in individuals with AUD. And finally, we detailedly reviewed the potential theranostics applications of gene therapy agents targeting ncRNAs in AUD mice. Overall, a deeper comprehension of functional roles and biological mechanisms of ncRNAs may make significant contributions to the accurate diagnosis and effective treatment of AUD.

Hippocampal ceRNA networks from chronic intermittent ethanol vapor-exposed male mice and functional analysis of top-ranked lncRNA genes for ethanol drinking phenotypes

The molecular mechanisms regulating the development and progression of alcohol use disorder (AUD) are largely unknown. While noncoding RNAs have previously been implicated as playing key roles in AUD, long-noncoding RNA (lncRNA) remains understudied in relation to AUD. In this study, we first identified ethanol-responsive lncRNAs in the mouse hippocampus that are transcriptional network hub genes. Microarray analysis of lncRNA, miRNA, circular RNA, and protein coding gene expression in the hippocampus from chronic intermittent ethanol vapor- or air- (control) exposed mice was used to identify ethanol-responsive competing endogenous RNA (ceRNA) networks. Highly interconnected lncRNAs (genes that had the strongest overall correlation to all other dysregulated genes identified) were ranked. The top four lncRNAs were novel, previously uncharacterized genes named Gm42575, 4930413E15Rik, Gm15767, and Gm33447, hereafter referred to as Pitt1, Pitt2, Pitt3, and Pitt4, respectively. We subsequently tested the hypothesis that CRISPR/Cas9 mutagenesis of the putative promoter and first exon of these lncRNAs in C57BL/6J mice would alter ethanol drinking behavior. The Drinking in the Dark (DID) assay was used to examine binge-like drinking behavior, and the Every-Other-Day Two-Bottle Choice (EOD-2BC) assay was used to examine intermittent ethanol consumption and preference. No significant differences between control and mutant mice were observed in the DID assay. Female-specific reductions in ethanol consumption were observed in the EOD-2BC assay for Pitt1, Pitt3, and Pitt4 mutant mice compared to controls. Male-specific alterations in ethanol preference were observed for Pitt1 and Pitt2. Female-specific increases in ethanol preference were observed for Pitt3 and Pitt4. Total fluid consumption was reduced in Pitt1 and Pitt2 mutants at 15% v/v ethanol and in Pitt3 and Pitt4 at 20% v/v ethanol in females only. We conclude that all lncRNAs targeted altered ethanol drinking behavior, and that lncRNAs Pitt1, Pitt3, and Pitt4 influenced ethanol consumption in a sex-specific manner. Further research is necessary to elucidate the biological mechanisms for these effects. These findings add to the literature implicating noncoding RNAs in AUD and suggest lncRNAs also play an important regulatory role in the disease.

RNA biomarkers for alcohol use disorder

Alcohol use disorder (AUD) is highly prevalent and one of the leading causes of disability in the US and around the world. There are some molecular biomarkers of heavy alcohol use and liver damage which can suggest AUD, but these are lacking in sensitivity and specificity. AUD treatment involves psychosocial interventions and medications for managing alcohol withdrawal, assisting in abstinence and reduced drinking (naltrexone, acamprosate, disulfiram, and some off-label medications), and treating comorbid psychiatric conditions (e.g., depression and anxiety). It has been suggested that various patient groups within the heterogeneous AUD population would respond more favorably to specific treatment approaches. For example, there is some evidence that so-called reward-drinkers respond better to naltrexone than acamprosate. However, there are currently no objective molecular markers to separate patients into optimal treatment groups or any markers of treatment response. Objective molecular biomarkers could aid in AUD diagnosis and patient stratification, which could personalize treatment and improve outcomes through more targeted interventions. Biomarkers of treatment response could also improve AUD management and treatment development. Systems biology considers complex diseases and emergent behaviors as the outcome of interactions and crosstalk between biomolecular networks. A systems approach that uses transcriptomic (or other -omic data, e.g., methylome, proteome, metabolome) can capture genetic and environmental factors associated with AUD and potentially provide sensitive, specific, and objective biomarkers to guide patient stratification, prognosis of treatment response or relapse, and predict optimal treatments. This Review describes and highlights state-of-the-art research on employing transcriptomic data and artificial intelligence (AI) methods to serve as molecular biomarkers with the goal of improving the clinical management of AUD. Considerations about future directions are also discussed.

Long Non-Coding RNAs: The New Frontier into Understanding the Etiology of Alcohol Use Disorder

Alcohol use disorder (AUD) is a complex, chronic, debilitating condition impacting millions worldwide. Genetic, environmental, and epigenetic factors are known to contribute to the development of AUD. Long non-coding RNAs (lncRNAs) are a class of regulatory RNAs, commonly referred to as the "dark matter" of the genome, with little to no protein-coding potential. LncRNAs have been implicated in numerous processes critical for cell survival, suggesting that they play important functional roles in regulating different cell processes. LncRNAs were also shown to display higher tissue specificity than protein-coding genes and have a higher abundance in the brain and central nervous system, demonstrating a possible role in the etiology of psychiatric disorders. Indeed, genetic (e.g., genome-wide association studies (GWAS)), molecular (e.g., expression quantitative trait loci (eQTL)) and epigenetic studies from postmortem brain tissues have identified a growing list of lncRNAs associated with neuropsychiatric and substance use disorders. Given that the expression patterns of lncRNAs have been associated with widespread changes in the transcriptome, including methylation, chromatin architecture, and activation or suppression of translational activity, the regulatory nature of lncRNAs may be ubiquitous and an innate component of gene regulation. In this review, we present a synopsis of the functional impact that lncRNAs may play in the etiology of AUD. We also discuss the classifications of lncRNAs, their known functional roles, and therapeutic advancements in the field of lncRNAs to further clarify the functional relationship between lncRNAs and AUD.

Identifying a novel biological mechanism for alcohol addiction associated with circRNA networks acting as potential miRNA sponges

Our lab and others have shown that chronic alcohol use leads to gene and miRNA expression changes across the mesocorticolimbic (MCL) system. Circular RNAs (circRNAs) are noncoding RNAs that form closed-loop structures and are reported to alter gene expression through miRNA sequestration, thus providing a potentially novel neurobiological mechanism for the development of alcohol dependence (AD). Genome-wide expression of circRNA was assessed in the nucleus accumbens (NAc) from 32 AD-matched cases/controls. Significant circRNAs (unadj. p ≤ 0.05) were identified via regression and clustered in circRNA networks via weighted gene co-expression network analysis (WGCNA). CircRNA interactions with previously generated mRNA and miRNA were detected via correlation and bioinformatic analyses. Significant circRNAs (N = 542) clustered in nine significant AD modules (FWER p ≤ 0.05), within which we identified 137 circRNA hubs. We detected 23 significant circRNA-miRNA-mRNA interactions (FDR ≤ 0.10). Among these, circRNA-406742 and miR-1200 significantly interact with the highest number of mRNA, including genes associated with neuronal functioning and alcohol addiction (HRAS, PRKCB, HOMER1, and PCLO). Finally, we integrate genotypic information that revealed 96 significant circRNA expression quantitative trait loci (eQTLs) (unadj. p ≤ 0.002) that showed significant enrichment within recent alcohol use disorder (AUD) and smoking genome-wide association study (GWAS). To our knowledge, this is the first study to examine the role of circRNA in the neuropathology of AD. We show that circRNAs impact mRNA expression by interacting with miRNA in the NAc of AD subjects. More importantly, we provide indirect evidence for the clinical importance of circRNA in the development of AUD by detecting a significant enrichment of our circRNA eQTLs among GWAS of substance abuse.

Targeting Epigenetic Mechanisms to Treat Alcohol Use Disorders (AUD)

BACKGROUND

The impact of abusive alcohol consumption on human health is remarkable. According to the World Health Organization (WHO), approximately 3.3 million people die annually because of harmful alcohol consumption (the figure represents around 5.9% of global deaths). Alcohol Use Disorder (AUD) is a chronic disease where individuals exhibit compulsive alcohol drinking and present negative emotional states when they do not drink. In the most severe manifestations of AUD, the individuals lose control over intake despite a decided will to stop drinking. Given the multiple faces and the specific forms of this disease, the term AUD often appears in the plural (AUDs). Since only a few approved pharmacological treatments are available to treat AUD and they do not apply to all individuals or AUD forms, the search for compounds that may help to eliminate the burden of the disease and complement other therapeutical approaches is necessary.

METHODS

This work reviews recent research focused on the involvement of epigenetic mechanisms in the pathophysiology of AUD. Excessive drinking leads to chronic and compulsive consumption that eventually damages the organism. The central nervous system is a key target and is the focus of this study. The search for the genetic and epigenetic mechanisms behind the intricated dysregulation induced by ethanol will aid researchers in establishing new therapy approaches.

CONCLUSION

Recent findings in the field of epigenetics are essential and offer new windows for observation and research. The study of small molecules that inhibit key epienzymes involved in nucleosome architecture dynamics is necessary in order to prove their action and specificity in the laboratory and to test their effectivity and safety in clinical trials with selected patients bearing defined alterations caused by ethanol.

Alcohol induced impairment/abnormalities in brain: Role of MicroRNAs

Alcohol is a highly toxic substance and has teratogenic properties that can lead to a wide range of developmental disorders. Excessive use of alcohol can change the structural and functional aspects of developed brain and other organs. Which can further lead to significant health, social and economic implications in many countries of the world. Convincing evidence support the involvement of microRNAs (miRNAs) as important post-transcriptional regulators of gene expression in neurodevelopment and maintenance. They also show differential expression following an injury. MiRNAs are the special class of small non coding RNAs that can modify the gene by targeting the mRNA and fine tune the development of cells to organs. Numerous pieces of evidences have shown the relationship between miRNA, alcohol and brain damage. These studies also show how miRNA controls different cellular mechanisms involved in the development of alcohol use disorder. With the increasing number of research studies, the roles of miRNAs following alcohol-induced injury could help researchers to recognize alternative therapeutic methods to treat/cure alcohol-induced brain damage. The present review summarizes the available data and brings together the important miRNAs, that play a crucial role in alcohol-induced brain damage, which will help in better understanding complex mechanisms. Identifying these miRNAs will not only expand the current knowledge but can lead to the identification of better targets for the development of novel therapeutic interventions.

The importance of non-coding RNAs in environmental stress-related developmental brain disorders: A systematic review of evidence associated with exposure to alcohol, anesthetic drugs, nicotine, and viral infections

Brain development is a dynamic and lengthy process that includes cell proliferation, migration, neurogenesis, gliogenesis, synaptogenesis, and pruning. Disruption of any of these developmental events can result in long-term outcomes ranging from brain structural changes, to cognitive and behavioral abnormality, with the mechanisms largely unknown. Emerging evidence suggests non-coding RNAs (ncRNAs) as pivotal molecules that participate in normal brain development and neurodevelopmental disorders. NcRNAs such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are transcribed from the genome but not translated into proteins. Many ncRNAs have been implicated as tuners of cell fate. In this review, we started with an introduction of the current knowledge of lncRNAs and miRNAs, and their potential roles in brain development in health and disorders. We then reviewed and discussed the evidence of ncRNA involvement in abnormal brain development resulted from alcohol, anesthetic drugs, nicotine, and viral infections. The complex connections among these ncRNAs were also discussed, along with potential overlapping ncRNA mechanisms, possible pharmacological targets for therapeutic/neuroprotective interventions, and potential biomarkers for brain developmental disorders.

Differential expression of H19, BC1, MIAT1, and MALAT1 long non-coding RNAs within key brain reward regions after repeated morphine treatment

Morphine-induced analgesic tolerance and dependence are significant limits of pain control; however, the exact molecular mechanisms underlying morphine tolerance and dependence have remained unclear. The role of long non-coding RNAs (lncRNAs) in morphine tolerance and dependence is yet to be determined. We aimed to explore the association of specific lncRNAs expression in key brain reward regions after repeated injection of morphine. Male Wistar rats received subcutaneous injections of twice-daily morphine (10 mg/kg) or saline (1 mL/kg) for eight days. On day 8 of the repeated injections, induction of morphine analgesic tolerance and dependence was confirmed through a hotplate test and a naloxone-precipitated withdrawal analysis, respectively. Expression of H19, BC1, MIAT1, and MALAT1 lncRNAs was determined from the midbrain, striatum, hypothalamus, prefrontal cortex (PFC), and hippocampus by real-time PCR on day 8 of the repeated injections. The H19 expression was significantly different between morphine-treated and control saline-treated rats in all investigated areas except for the hippocampus. The BC1 expression significantly altered in the midbrain, hypothalamus, and hippocampus, but not in the striatum and PFC after repeated morphine treatment. The MIAT1 and MALAT1 expression site-specifically altered in the midbrain, hypothalamus, and striatum; however, no significant changes were detected in their expression in the PFC and hippocampus after repeated morphine treatment. We conclude that alterations in the expression of these lncRNAs in the brain reward regions especially in the midbrain, striatum and hypothalamus may have critical roles in the development of morphine dependence and tolerance, which need to be considered in future researches.

High ethanol preference and dissociated memory are co-occurring phenotypes associated with hippocampal GABAAR-δ receptor levels

Alcohol use disorder (AUD) frequently co-occurs with dissociative disorders and disorders with dissociative symptoms, suggesting a common neurobiological basis. It has been proposed that facilitated information processing under the influence of alcohol, resulting in the formation of dissociated memories, might be an important factor controlling alcohol use. Access to such memories is facilitated under the effect of alcohol, thus further reinforcing alcohol use. To interrogate possible mechanisms associated with these phenotypes, we used a mouse model of dissociative amnesia, combined with a high-alcohol preferring (HAP) model of AUD. Dissociated memory was induced by activation of hippocampal extrasynaptic GABA type A receptor delta subunits (GABA_AR-δ), which control tonic inhibition and to which ethanol binds with high affinity. Increased ethanol preference was associated with increased propensity to form dissociated memories dependent on GABA_AR-δ in the dorsal hippocampus (DH). Furthermore, the DH level of GABA_AR-δ protein, but not mRNA, was increased in HAP mice, and was inversely correlated to the level of miR-365-3p, suggesting an miRNA-mediated post-transcriptional mechanism contributing to elevated GABA_AR-δ. The observed changes of DH GABA_AR-δ were associated with a severe reduction of excitatory projections stemming from GABA_AR-δ-containing pyramidal neurons in the subiculum and terminating in the mammillary body. These results suggest that both molecular and circuit dysfunction involving hippocampal GABA_AR-δ receptors might contribute to the co-occurrence of ethanol preference and dissociated information processing.

Exposure to drugs of abuse induce effects that persist across generations

Substance use disorders are highly prevalent and continue to be one of the leading causes of disability in the world. Notably, not all people who use addictive drugs develop a substance use disorder. Although substance use disorders are highly heritable, patterns of inheritance cannot be explained purely by Mendelian genetic mechanisms. Vulnerability to developing drug addiction depends on the interplay between genetics and environment. Additionally, evidence from the past decade has pointed to the role of epigenetic inheritance in drug addiction. This emerging field focuses on how environmental perturbations, including exposure to addictive drugs, induce epigenetic modifications that are transmitted to the embryo at fertilization and modify developmental gene expression programs to ultimately impact subsequent generations. This chapter highlights intergenerational and transgenerational phenotypes in offspring following a history of parental drug exposure. Special attention is paid to parental preconception exposure studies of five drugs of abuse (alcohol, cocaine, nicotine, cannabinoids, and opiates) and associated behavioral and physiological outcomes in offspring. The highlighted studies demonstrate that parental exposure to drugs of abuse has enduring effects that persist into subsequent generations. Understanding the contribution of epigenetic inheritance in drug addiction may provide clues for better treatments and therapies for substance use disorders.

Epigenetic mechanisms underlying pathobiology of alcohol use disorder

Purpose of review

Chronic alcohol use is a worldwide problem with multifaceted consequences including multiplying medical costs and sequelae, societal effects like drunk driving and assault, and lost economic productivity. These large-scale outcomes are driven by the consumption of ethanol, a small permeable molecule that has myriad effects in the human body, particularly in the liver and brain. In this review, we have summarized effects of acute and chronic alcohol consumption on epigenetic mechanisms that may drive pathobiology of Alcohol Use Disorder (AUD) while identifying areas of need for future research.

Recent findings

Epigenetics has emerged as an interesting field of biology at the intersection of genetics and the environment, and ethanol in particular has been identified as a potent modulator of the epigenome with various effects on DNA methylation, histone modifications, and non-coding RNAs. These changes alter chromatin dynamics and regulate gene expression that contribute to behavioral and physiological changes leading to the development of AUD psychopathology and cancer pathology.

Summary

Evidence and discussion presented here from preclinical results and available translational studies have increased our knowledge of the epigenetic effects of alcohol consumption. These studies have identified targets that can be used to develop better therapies to reduce chronic alcohol abuse and mitigate its societal burden and pathophysiology.

Single cell transcriptome profiling of the human alcohol-dependent brain

Alcoholism remains a prevalent health concern throughout the world. Previous studies have identified transcriptomic patterns in the brain associated with alcohol dependence in both humans and animal models. But none of these studies have systematically investigated expression within the unique cell types present in the brain. We utilized single nucleus RNA sequencing (snRNA-seq) to examine the transcriptomes of over 16 000 nuclei isolated from the prefrontal cortex of alcoholic and control individuals. Each nucleus was assigned to one of seven major cell types by unsupervised clustering. Cell type enrichment patterns varied greatly among neuroinflammatory-related genes, which are known to play roles in alcohol dependence and neurodegeneration. Differential expression analysis identified cell type-specific genes with altered expression in alcoholics. The largest number of differentially expressed genes (DEGs), including both protein-coding and non-coding, were detected in astrocytes, oligodendrocytes and microglia. To our knowledge, this is the first single cell transcriptome analysis of alcohol-associated gene expression in any species and the first such analysis in humans for any addictive substance. These findings greatly advance the understanding of transcriptomic changes in the brain of alcohol-dependent individuals.

LncRNA ANCR downregulates hypoxia‑inducible factor 1α and inhibits the growth of HPV‑negative cervical squamous cell carcinoma under hypoxic conditions

Long non‑coding RNA (lncRNA) anti‑differentiation non‑coding RNA (ANCR) has been reported to participate in numerous types of malignancies. The present study aimed to investigate the function of lncRNA ANCR in cervical squamous cell carcinoma (CSCC). The expression of ANCR in the cervical tissues (tumor tissues in patients with CSCC) and serum of patients with CSCC in addition to healthy female controls was detected using reverse transcription‑quantitative polymerase chain reaction. Diagnostic values of ANCR expression in cervical tissue and serum for CSCC were determined using receiver operating characteristic curve analysis. LncRNA ANCR and hypoxia‑inducible factor 1α (HIF‑1α) expression vectors were constructed and transfected into CSCC cell lines, and cell proliferation under normal O2 and hypoxic conditions (8% O2) was detected using a Cell Counting kit‑8 assay. Expression of HIF‑1α was determined using western blot analysis. It was observed that ANCR was downregulated in human papillomavirus (HPV)‑negative patients with CSCC compared with in normal female cases and HPV‑positive patients with CSCC in cervical tissues and in the serum, and the downregulation of ANCR effectively distinguished HPV‑negative patients with CSCC from healthy controls. ANCR overexpression inhibited the proliferation of HPV‑negative CSCC cells under hypoxic conditions, whilst HIF‑1α overexpression reversed this effect. ANCR overexpression inhibited HIF‑1α expression in HPV‑negative CSCC cells, while HIF‑1α overexpression exhibited no significant effect on ANCR expression. It was therefore concluded that ANCR may inhibit the growth of HPV‑negative cervical squamous cell carcinoma under hypoxic conditions by downregulating HIF‑1α.

LncRNA CAIF was downregulated in end-stage cardiomyopathy and is a promising diagnostic and prognostic marker for this disease

Cardiac autophagy inhibitory factor (CAIF) is a novel lncRNA with protective effects on myocardial infarction. We explored the involvement of CAIF in end-stage cardiomyopathy. Patients with end-stage cardiomyopathy and healthy volunteers were included in this study. Myocardial tissues and serum were collected. CAIF was detected by RT-qPCR. ROC curve was used for diagnostic analysis. Prognostic value of CAIF expression for end-stage cardiomyopathy was evaluated by survival curve analysis. Correlations between CAIF expression and clinicopathological data of patients with end-stage cardiomyopathy were analysed by chi-square test. Downregulated CAIF was observed in end-stage cardiomyopathy patients than in healthy controls. CAIF expression distinguished end-stage cardiomyopathy patients from healthy controls and predict the survival of patients. LncRNA CAIF was downregulated in end-stage cardiomyopathy and may serve as a promising prognostic and diagnostic marker for this disease.

Upregulation of lncRNA GATA6-AS suppresses the migration and invasion of cervical squamous cell carcinoma by downregulating MTK-1

The diagnosis and treatment of cervical squamous cell carcinoma is challenged by difficulties in the determination of tumor invasion. GATA binding protein 6 antisense (GATA6-AS) is a recently identified long non-coding RNA that exhibits critical functions in the growth of endothelial cells; however, to the best of our knowledge, its involvement in other physiological and pathological processes is unknown. By reverse transcription-quantitative polymerase chain reaction, the present study examined the expression of GATA6-AS in tumor tissues and adjacent healthy tissues, and the serum from patients with cervical squamous cell carcinoma and healthy controls. The diagnostic and prognostic potentials of GATA6-AS for cervical squamous cell carcinoma were analyzed by receiver operating characteristic curve analysis and survival curve analysis, respectively. Associations between the serum levels of GATA6-AS and clinical characteristics of patients with cervical squamous cell carcinoma were analyzed by a χ² test. A GATA6-AS overexpression vector was transfected into cervical squamous cell carcinoma cells, and the effects on cell migration and invasion were investigated by Transwell migration and invasion assays, respectively. The expression of mitogen-activated protein kinase kinase 4 (MTK-1) following transfection with the GATA6-AS overexpression vector was detected by western blot analysis. It was identified that the expression levels of GATA6-AS were lower in tumor tissues compared with healthy tissues. In addition, serum levels of GATA6-AS were higher in patients compared with healthy controls. The serum levels of GATA6-AS were associated with tumor metastasis, and may serve as a potential diagnostic and prognostic marker for cervical squamous cell carcinoma. Furthermore, GATA6-AS overexpression inhibited cancer cell migration and invasion. The expression levels of MTK-1 were also reduced following GATA6-AS overexpression. Therefore, the present study proposed that downregulated GATA6-AS expression was associated with tumor metastasis in cervical squamous cell carcinoma, and that GATA6-AS expression may inhibit cancer cell migration and invasion by downregulating MTK-1.

Silencing synaptic MicroRNA-411 reduces voluntary alcohol consumption in mice

Chronic alcohol consumption alters the levels of microRNAs and mRNAs in the brain, but the specific microRNAs and processes that target mRNAs to affect cellular function and behavior are not known. We examined the in vivo manipulation of previously identified alcohol-responsive microRNAs as potential targets to reduce alcohol consumption. Silencing of miR-411 by infusing antagomiR-411 into the prefrontal cortex of female C57BL/6J mice reduced alcohol consumption and preference, without altering total fluid consumption, saccharin consumption, or anxiety-related behaviors. AntagomiR-411 reduced alcohol consumption when given to mice exposed to a chronic alcohol drinking paradigm but did not affect the acquisition of consumption in mice without a history of alcohol exposure, suggesting that antagomiR-411 has a neuroadaptive, alcohol-dependent effect. AntagomiR-411 decreased the levels of miR-411, as well as the association of immunoprecipitated miR-411 with Argonaute2; and, it increased levels of Faah and Ppard mRNAs. Moreover, antagomiR-411 increased the neuronal expression of glutamate receptor AMPA-2 protein, a known alcohol target and a predicted target of miR-411. These results suggest that alcohol and miR-411 function in a homeostatic manner to regulate synaptic mRNA and protein, thus reversing alcohol-related neuroadaptations and reducing chronic alcohol consumption.

LncRNA AWPPH promotes the proliferation, migration and invasion of ovarian carcinoma cells via activation of the Wnt/β‑catenin signaling pathway

The oncogenic role of the long noncoding RNA associated with poor prognosis of hepatocellular carcinoma (lncRNA AWPPH) was reported in various types of malignancies; however, its involvement in ovarian carcinoma (OC) remains unknown. Thus, the present study investigated the role of AWPPH in OC. The expression of AWPPH in tissues and serum acquired from patients with OC, and healthy controls, was determined via reverse transcription‑quantitative polymerase chain reaction. The diagnostic value of serum AWPPH expression was evaluated by receiver operating characteristic curve analysis. Additionally, survival curve analysis was performed to determine the prognostic value of AWPPH for OC. An AWPPH overexpression vector was transfected into OC cell lines. Cell proliferation, migration and invasion were analyzed via Cell Counting Kit‑8, Transwell migration and invasion assays, respectively. The expression of β‑catenin was investigated via western blotting. It was revealed that the expression levels of AWPPH were significantly upregulated in OC tissues and serum compared with healthy controls. The serum levels of AWPPH were able to effectively diagnose and predict the prognosis of patients with OC. AWPPH overexpression promoted the proliferation, migration and invasion of OC cells, and upregulated β‑catenin expression. Treatment with a Wnt agonist markedly altered AWPPH expression; however, inhibition of Wnt suppressed the effects of AWPPH overexpression on proliferation, migration and invasion of OC cells. Therefore, it was revealed that AWPPH may promote OC via activation of the Wnt/β‑catenin signaling pathway.

LncRNA GASL1 inhibits growth and promotes expression of apoptosis-associated proteins in prostate carcinoma cells through GLUT-1

Growth-arrest-associated long non-coding (lnc)RNA 1 (GASL1) is as newly identified lncRNA that is associated with liver cancer. The present study aimed to investigate the role of GASL1 in prostate carcinoma (PC). Expression levels of GASL1 in prostate tissues and sera from patients with PC and from healthy subjects were detected by reverse transcription-quantitative polymerase chain reaction. Receiver operating characteristic and survival curve analyses were performed to evaluate the diagnostic and prognostic values of GASL1 for patients with PC. A GASL1 expression vector was transfected into PC cells prior to assessment of cell proliferation and expression of B cell lymphoma 2 (Bcl-2) and glucose transporter 1 (GLUT-1) by Cell Counting Kit-8 and western blotting, respectively. The results demonstrated that GASL1 was significantly downregulated in the tissue and serum of patients with PC compared to those of healthy subjects. In addition, GASL1 was used to distinguish patients with PC from healthy controls, and low expression levels of GASL1 were associated with short survival time. Expression levels of GASL1 were significantly associated with tumor size. GASL1 overexpression inhibited PC cell growth. Overexpression of GASL1 upregulated Bcl-2 expression and downregulated GLUT-1 expression. In conclusion, these data suggested that lncRNA GASL1 may inhibit PC cell proliferation by targeting GLUT-1.

lncRNA AWPPH promotes proliferation and inhibits apoptosis of non‑small cell lung cancer cells by activating the Wnt/β‑catenin signaling pathway

AWPPH is a newly discovered long non‑coding (lnc)RNA that serves an oncogenic role in the development of several types of cancer; however, its involvement in non‑small cell lung cancer (NSCLC) is unknown. Therefore, the aim of the present study was to investigate the function of AWPPH in NSCLC. The results demonstrated that AWPPH expression levels were significantly upregulated in the lung tissues and serum samples of patients with NSCLC compared with in healthy controls. High expression levels of AWPPH effectively distinguished NSCLC patients from healthy controls. In addition, patients with high expression levels of AWPPH had significantly shorter survival time. AWPPH overexpression in NSCLC cells promoted proliferation and inhibited apoptosis, and activated the Wnt/β‑catenin signaling pathway, which is a classic signaling pathway involved in the development and progression of different types of cancers. Treatment with a Wnt/β‑catenin signaling pathway activator produced no significant effect on AWPPH expression. Therefore, it was concluded that lcRNA AWPPH could promote the growth of NSCLCs by activating the Wnt/β‑catenin signaling pathway.

Effect of ethanol on lipid metabolism

Hepatic lipid metabolism is a series of complex processes that control influx and efflux of not only hepatic lipid pools, but also organismal pools. Lipid homeostasis is usually tightly controlled by expression, substrate supply, oxidation and secretion that keep hepatic lipid pools relatively constant. However, perturbations of any of these processes can lead to lipid accumulation in the liver. Although it is thought that these responses are hepatic arms of the 'thrifty genome', they are maladaptive in the context of chronic fatty liver diseases. Ethanol is likely unique among toxins, in that it perturbs almost all aspects of hepatic lipid metabolism. This complex response is due in part to the large metabolic demand placed on the organ by alcohol metabolism, but also appears to involve more nuanced changes in expression and substrate supply. The net effect is that steatosis is a rapid response to alcohol abuse. Although transient steatosis is largely an inert pathology, the chronicity of alcohol-related liver disease seems to require steatosis. Better and more specific understanding of the mechanisms by which alcohol causes steatosis may therefore translate into targeted therapies to treat alcohol-related liver disease and/or prevent its progression.

EPEL promotes the migration and invasion of osteosarcoma cells by upregulating ROCK1

E2F-mediated cell proliferation enhancing long non-coding RNA (lncRNA) (EPEL) is a newly identified lncRNA involved in the regulation of lung cancer cell proliferation. However, its association with other types of cancer is unknown. The present study recruited patients with osteosarcoma and healthy controls. Tumor and adjacent healthy tissues were obtained from patients with osteosarcoma, and whole blood was extracted from patients and healthy controls. The expression levels of EPEL in tissues were detected by reverse transcription-quantitative polymerase chain reaction. The diagnostic value of serum EPEL for osteosarcoma was evaluated by receiver operating characteristic curve analysis. The association between serum levels of EPEL and basic clinical patient information was analyzed by χ² test. Subsequently, EPEL overexpression in osteosarcoma cell lines was established, and its effects on cell migration and invasion were explored by Transwell assay. The implications of EPEL overexpression on Rho-associated coiled-coil containing protein kinase 1 (ROCK1) expression were investigated by western blotting. The results revealed that EPEL was upregulated in tumor tissues compared with adjacent tissues. In addition, serum levels of EPEL were higher in patients with osteosarcoma compared with healthy controls, and were positively associated with distant tumor metastasis. Furthermore, EPEL overexpression promoted the migration and invasion of osteosarcoma cells and induced overexpression of ROCK1. In conclusion, these results suggested that EPEL may promote the migration and invasion of osteosarcoma cells by upregulating ROCK1.

The diagnostic value and pathogenetic role of lncRNA-ATB in patients with osteoarthritis

Background

In view of the roles of long non-coding RNAs (lncRNAs) in human diseases and the high incidence of osteoarthritis, we investigated the role of long non-coding RNA activated by transforming growth factor-β (lncRNA-ATB) in osteoarthritis and explored its diagnostic value for this disease.

Methods

The study involved 98 patients with osteoarthritis and 76 healthy subjects. Blood was extracted from each participant and the expression of lncRNA-ATB in the serum was detected using quantitative Real Time -PCR. ROC curve analysis was performed to evaluate the diagnostic value of lncRNA-ATB for osteoarthritis. Based on the median serum level of lncRNA-ATB, patients were divided into a high-level group and a low-level group. Correlations between the serum levels of lncRNA-ATB and basic information about the patients were analyzed using the chi-square test. LncRNA-ATB overexpression in human chondrocyte cell line CHON-001 (ATCC CRL-2846) was established to study the effects on chondrocyte proliferation (using the CCK-8 assay) and viability.

Results

LncRNA-ATB expression was significantly downregulated in the serum of osteoarthritis patients compared with the healthy controls, meaning this downregulation effectively distinguished osteoarthritis patients from healthy subjects. LncRNA-ATB expression in the serum was not significantly affected by the patients’ gender, age or habits, including smoking and alcohol consumption. LncRNA-ATB overexpression activated Akt signaling, promoted proliferation and increased the viability of the chondrocytes.

Conclusion

We conclude that downregulation of lncRNA-ATB in serum is a reliable diagnostic marker for osteoarthritis and that this lncRNA participates in the pathogenesis of osteoarthritis by regulating the proliferation and viability of chondrocytes through the activation of Akt signaling.

Electronic supplementary material

The online version of this article (10.1186/s11658-018-0118-9) contains supplementary material, which is available to authorized users.

Downregulation of lncRNA CASC2 promotes the postoperative local recurrence of early oral squamous cell carcinoma

PURPOSE

LncRNA CASC2 plays a role as tumor suppressor gene in different types of human malignancies, while its involvement in oral squamous cell carcinoma (OSCC) is unknown. The present study aimed to investigate the involvement of lncRNA CASC2 in OSCC.

METHODS

In this study, the expression of lncRNA CASC2 in tumor tissues, adjacent healthy tissues, and plasma of 122 OSCC patients as well as in plasma of 52 healthy controls was detected by RT-qPCR. Diagnostic value of lncRNA CASC2 for OSCC was evaluated by ROC curve analysis. Patients were followed up for 5 years to record recurrence. LncRNA CASC2 expression vectors were transfected into cells of human OSCC cell lines, and the effects on cancer cell proliferation and miRNA-21 expression were analyzed by CCK-8 assay and RT-qPCR, respectively.

RESULTS

We found that CASC2 was significantly downregulated in OSCC patients than in healthy controls. Downregulation of CASC2 distinguished OSCC patients from healthy controls. Local recurrence was observed in 26 out of 122 patients and no distant recurrence was observed during follow-up. Compared with pretreatment levels, plasma levels of CASC2 were significantly increased in patients with local recurrence than in patients without recurrence. Transfection of CASC2 expression vectors led to significantly inhibited tumor cell proliferation and reduced miRNA-21 expression levels.

CONCLUSIONS

We, therefore, conclude that downregulation of lncRNA CASC2 may participate in the postoperative local recurrence of early OSCC through miRNA-21.

LncRNA HOTAIR improves diabetic cardiomyopathy by increasing viability of cardiomyocytes through activation of the PI3K/Akt pathway

The current study aimed to investigate the role of long non-coding RNA (lncRNA) homeobox transcript antisense RNA (HOTAIR) in the pathogenesis of diabetic cardiomyopathy. Patients with diabetic cardiomyopathy, patients with diabetes but without cardiomyopathy and healthy controls were included in the current study. All participants underwent myocardial biopsy to collect myocardial tissues. Blood samples were also collected from each participant to prepare serum. Expression of HOTAIR in myocardial tissues was detected by reverse transcription-quantitative polymerase chain reaction. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic value of serum HOTAIR for diabetic cardiomyopathy. AC16 human cardiomyocyte cells were treated with high glucose to observe the changes in expression of HOTAIR and phosphorylation of Akt. HOTAIR expression vector was transfected into cells of AC16 cell line and the effects of HOTAIR overexpression on cell viability and Akt phosphorylation were detected by MTT assay and western blot analysis, respectively. HOTAIR expression was significantly downregulated in myocardial tissues and serum of patients with diabetic cardiomyopathy compared with patients with diabetes and healthy controls. Serum HOTAIR could be used to effectively distinguish patients with diabetic cardiomyopathy from healthy controls. High glucose treatment inhibited HOTAIR expression and Akt phosphorylation. HOTAIR overexpression promoted Akt phosphorylation. HOTAIR overexpression improved AC16 cell viability, while PI3K/Akt inhibitor treatment reduced this effect. LncRNA HOTAIR may improve diabetic cardiomyopathy by increasing the viability of cardiomyocytes through activation of the PI3K/Akt pathway.

Neuroepigenetics and addictive behaviors: Where do we stand?

Substance use disorders involve long-term changes in the brain that lead to compulsive drug seeking, craving, and a high probability of relapse. Recent findings have highlighted the role of epigenetic regulations in controlling chromatin access and regulation of gene expression following exposure to drugs of abuse. In the present review, we focus on data investigating genome-wide epigenetic modifications in the brain of addicted patients or in rodent models exposed to drugs of abuse, with a particular focus on DNA methylation and histone modifications associated with transcriptional studies. We highlight critical factors for epigenomic studies in addiction. We discuss new findings related to psychostimulants, alcohol, opiate, nicotine and cannabinoids. We examine the possible transmission of these changes across generations. We highlight developing tools, specifically those that allow investigation of structural reorganization of the chromatin. These have the potential to increase our understanding of alteration of chromatin architecture at gene regulatory regions. Neuroepigenetic mechanisms involved in addictive behaviors could explain persistent phenotypic effects of drugs and, in particular, vulnerability to relapse.

lncRA ANCR Inhibits Non-Small Cell Lung Cancer Cell Migration and Invasion by Inactivating TGF-β Pathway

Background

lncRNA ANCR is proved to be a tumor suppressor gene only in colorectal cancer and breast cancer. Our study aimed to explore the possible involvement of ACNR in non-small cell lung cancer (NSCLC).

Material/Methods

In this study, we first detected the expression of ACNR in lung biopsies and plasma of both NSCLC patients and healthy controls. The diagnostic value of ANCR for NSCLC was analyzed by ROC curve analysis. Follow-up data of NSCLC patients was analyzed and the prognostic value of ANCR was analyzed by survival curve analysis. ANCR expression vector was transfected into cells of human NSCLC cell lines, and the effects on cell migration and invasion were explored by Transwell migration and invasion assays, respectively. TGF-β1 expression after ANCR overexpression was detected by Western blot analysis.

Results

ANCR was significantly downregulated in NSCLC patients compared with healthy controls in lung biopsies and plasma. Downregulated expression of ANCR distinguishes NSCLC patients from healthy controls and low NSCLC expression level indicates shorter postoperative survival time of NSCLC patients. ANCR overexpression inhibited NSCLC cell migration and invasion and downregulated TGF-β1 expression, while TGF-β1 treatment showed no significant effects on ANCR expression but promoted NSCLC cell migration and invasion. In addition, TGF-β1 treatment also attenuated the inhibitory effects of ANCR overexpression on NSCLC cell migration and invasion.

Conclusions

ANCR can inhibit NSCLC cell migration and invasion by downregulating TGF-β1 expression.

Downregulation of lncRNA TUG1 is involved in ankylosing spondylitis and is related to disease activity and course of treatment

Long non-coding RNA taurine-upregulated gene 1 (lncRNA TUG1) promotes osteosarcoma, while its involvement in other bone diseases, such as ankylosing spondylitis (AS) is unknown. Expression of TUG1 in serum and open sacroiliac biopsies of AS patents and healthy controls was detected by real-time quantitative PCR (qRT-PCR). Ankylosing spondylitis disease activity score (ASDAS) system was used to evaluate disease activity. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of lncRNA TUG1 for AS. Chi-square test was performed to analyze the correlations between TUG1 expression and patients' clinicopathological data. Patients were divided into 2 groups (high and low expression groups) according to the median expression level of TUG1 and were followed-up for 5 years after discharge. Treatment courses and rehospitalization rate were compared between two groups. It was observed that TUG1 expression level was significantly lower in AS patients than in healthy controls in both serum and biopsies. Reduced expression level of TUG1 distinguished AS patients from controls. LncRNA TUG1 expression was significantly correlated with patients' smoking habits, disease activity, and course of disease. Patients in high expression group showed longer hospitalization time and higher rehospitalization rate. We therefore conclude that expression of lncRNA TUG1 was inhibited in AS patients and downregulation of lncRNA TUG1 is related to higher disease activity, longer course of treatment and higher rehospitalization rate.

A non-coding CRHR2 SNP rs255105, a cis-eQTL for a downstream lincRNA AC005154.6, is associated with heroin addiction

Dysregulation of the stress response is implicated in drug addiction; therefore, polymorphisms in stress-related genes may be involved in this disease. An analysis was performed to identify associations between variants in 11 stress-related genes, selected a priori, and heroin addiction. Two discovery samples of American subjects of European descent (EA, n = 601) and of African Americans (AA, n = 400) were analyzed separately. Ancestry was verified by principal component analysis. Final sets of 414 (EA) and 562 (AA) variants were analyzed after filtering of 846 high-quality variants. The main result was an association of a non-coding SNP rs255105 in the CRH (CRF) receptor 2 gene (CRHR2), in the discovery EA sample (Pnominal = .00006; OR = 2.1; 95% CI 1.4-3.1). The association signal remained significant after permutation-based multiple testing correction. The result was corroborated by an independent EA case sample (n = 364). Bioinformatics analysis revealed that SNP rs255105 is associated with the expression of a downstream long intergenic non-coding RNA (lincRNA) gene AC005154.6. AC005154.6 is highly expressed in the pituitary but its functions are unknown. LincRNAs have been previously associated with adaptive behavior, PTSD, and alcohol addiction. Further studies are warranted to corroborate the association results and to assess the potential relevance of this lincRNA to addiction and other stress-related disorders.

Gender-Specific Effects of Selection for Drinking in the Dark on the Network Roles of Coding and Noncoding RNAs

BACKGROUND

Transcriptional differences between heterogeneous stock mice and high drinking-in-the-dark selected mouse lines have previously been described based on microarray technology coupled with network-based analysis. The network changes were reproducible in 2 independent selections and largely confined to 2 distinct network modules; in contrast, differential expression appeared more specific to each selected line. This study extends these results by utilizing RNA-Seq technology, allowing evaluation of the relationship between genetic risk and transcription of noncoding RNA (ncRNA); we additionally evaluate sex-specific transcriptional effects of selection.

METHODS

Naïve mice (N = 24/group and sex) were utilized for gene expression analysis in the ventral striatum; the transcriptome was sequenced with the Illumina HiSeq platform. Differential gene expression and the weighted gene co-expression network analysis were implemented largely as described elsewhere, resulting in the identification of genes that change expression level or (co)variance structure.

RESULTS

Across both sexes, we detect selection effects on the extracellular matrix and synaptic signaling, although the identity of individual genes varies. A majority of nc RNAs cluster in a single module of relatively low density in both the male and female network. The most strongly differentially expressed transcript in both sexes was Gm22513, a small nuclear RNA with unknown function. Associated with selection, we also found a number of network hubs that change edge strength and connectivity. At the individual gene level, there are many sex-specific effects; however, at the annotation level, results are more concordant.

CONCLUSIONS

In addition to demonstrating sex-specific effects of selection on the transcriptome, the data point to the involvement of extracellular matrix genes as being associated with the binge drinking phenotype.

LncRNA PlncRNA-1 overexpression inhibits the growth of breast cancer by upregulating TGF-β1 and downregulating PHGDH

OBJECTIVE

To investigate the role of lncRNA PlncRNA-1 in the pathogenesis of breast cancer.

METHODS

A total of 78 patients with breast cancer as well as 48 healthy females were included in this study. Expression in tumor tissues and adjacent healthy tissues of breast cancer patients, as well as in breast tissues and serum of both patients and healthy control was detected by qRT-PCR. Cell proliferation was detected by CCK-8 assay, and cell apoptosis was tested by MTT assay. PlncRNA-1 overexpression cell lines were constructed and the effects on TGF-β1 as well as phosphoglycerate dehydrogenase (PHGDH) were explored by western blot.

RESULTS

Expression levels of PlncRNA-1 were significantly lower in tumor tissues than those in adjacent healthy tissues. Significantly lower expression levels of PlncRNA-1 were also found in breast cancer patients than those in healthy controls in both breast tissue and serum. Upregulation of PlncRNA-1 promoted the expression of TGF-β1, but inhibited the expression of PHGDH. LncRNA PlncRNA-1 overexpression reduced the proliferation rate, but increased the apoptosis rate of breast cancer cells, while treatment with TGF-β inhibitor reduced those effects of PlncRNA-1 overexpression.

CONCLUSION

LncRNA PlncRNA-1 overexpression inhibits the growth of breast cancer by upregulating TGF-β1 and downregulating PHGDH.

Epigenetics as a Driver of Developmental Origins of Health and Disease: Did We Forget the Fathers?

What are the effects of our environment on human development and the next generation? Numerous studies have provided ample evidence that a healthy environment and lifestyle of the mother is important for her offspring. Biological mechanisms underlying these environmental influences have been proposed to involve alterations in the epigenome. Is there enough evidence to suggest a similar contribution from the part of the father? Animal models provide proof of a transgenerational epigenetic effect through the paternal germ line, but can this be translated to humans? To date, literature on fathers is scarce. Human studies do not always incorporate appropriate tools to evaluate paternal influences or epigenetic effects. In reviewing the literature, I stress the need to explore and recognize paternal contributions to offspring's health within the Developmental Origins of Health and Disease hypothesis, and coin this new concept the Paternal Origins of Health and Disease paradigm (POHaD). A better understanding of preconceptional origins of disease through the totality of paternal exposures, or the paternal exposome, will provide evidence-based public health recommendations for future fathers.