Differential expression of GAS5 in rapamycin-induced reversion of glucocorticoid resistance

Long non-coding RNAs as pathophysiological regulators, therapeutic targets and novel extracellular vesicle biomarkers for the diagnosis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic relapsing disease of the gastrointestinal (GI) system that includes two groups, Crohn's disease (CD) and ulcerative colitis (UC). To cope with these two classes of IBD, the investigation of pathogenic mechanisms and the discovery of new diagnostic and therapeutic approaches are crucial. Long non-coding RNAs (lncRNAs) which are non-coding RNAs with a length of longer than 200 nucleotides have indicated significant association with the pathology of IBD and strong potential to be used as accurate biomarkers in diagnosing and predicting responses to the IBD treatment. In the current review, we aim to investigate the role of lncRNAs in the pathology and development of IBD. We first describe recent advances in research on dysregulated lncRNAs in the pathogenesis of IBD from the perspective of epithelial barrier function, intestinal immunity, mitochondrial function, and intestinal autophagy. Then, we highlight the possible translational role of lncRNAs as therapeutic targets, diagnostic biomarkers, and predictors of therapeutic response in colon tissues and plasma samples. Finally, we discuss the potential of extracellular vesicles and their lncRNA cargo in the pathophysiology, diagnosis, and treatment of IBD.

Long Non-Coding RNAs and Their "Discrete" Contribution to IBD and Johne's Disease-What Stands out in the Current Picture? A Comprehensive Review

Non-coding RNAs (ncRNA) have paved the way to new perspectives on the regulation of gene expression, not only in biology and medicine, but also in associated fields and technologies, ensuring advances in diagnostic means and therapeutic modalities. Critical in this multistep approach are the associations of long non-coding RNA (lncRNA) with diseases and their causal genes in their networks of interactions, gene enrichment and expression analysis, associated pathways, the monitoring of the involved genes and their functional roles during disease progression from one stage to another. Studies have shown that Johne's Disease (JD), caused by Mycobacterium avium subspecies partuberculosis (MAP), shares common lncRNAs, clinical findings, and other molecular entities with Crohn's Disease (CD). This has been a subject of vigorous investigation owing to the zoonotic nature of this condition, although results are still inconclusive. In this review, on one hand, the current knowledge of lncRNAs in cells is presented, focusing on the pathogenesis of gastrointestinal-related pathologies and MAP-related infections and, on the other hand, we attempt to dissect the associated genes and pathways involved. Furthermore, the recently characterized and novel lncRNAs share common pathologies with IBD and JD, including the expression, molecular networks, and dataset analysis results. These are also presented in an attempt to identify potential biomarkers pertinent to cattle and human disease phenotypes.

Anti-Leukemic Effects of Idesia polycarpa Maxim Branch on Human B-Cell Acute Lymphoblastic Leukemia Cells

Patients with pediatric B-cell acute lymphoblastic leukemia (B-ALL) have a high survival rate, yet the prognosis of adults and patients with relapsed/refractory disease is relatively poor. Therefore, it is imperative to develop new therapeutic strategies. Here, we screened 100 plant extracts from South Korean Flora and investigated their anti-leukemic effect using CCRF-SB cells as a B-ALL model. The top cytotoxic extract identified in this screening was the Idesia polycarpa Maxim. branch (IMB), which efficiently inhibited the survival and proliferation of CCRF-SB cells, while having minimal to no impact on normal murine bone marrow cells. Mechanistically, the IMB-induced proapoptotic effect involves the increase of caspase 3/7 activity, which was shown to be associated with the disruption of the mitochondrial membrane potential (MMP) through the reduction in antiapoptotic Bcl-2 family expression. IMB also promoted the differentiation of CCRF-SB cells via the upregulation of the expression of differentiation-related genes, PAX5 and IKZF1. Given that resistance to glucocorticoid (GC) is often found in patients with relapsed/refractory ALL, we investigated whether IMB could restore GC sensitivity. IMB synergized GC to enhance apoptotic rate by increasing GC receptor expression and downmodulating mTOR and MAPK signals in CCRF-SB B-ALL cells. These results suggest that IMB has the potential to be a novel candidate for the treatment of B-ALL.

Non-Coding RNA Signatures of B-Cell Acute Lymphoblastic Leukemia

Non-coding RNAs (ncRNAs) comprise a diverse class of non-protein coding transcripts that regulate critical cellular processes associated with cancer. Advances in RNA-sequencing (RNA-Seq) have led to the characterization of non-coding RNA expression across different types of human cancers. Through comprehensive RNA-Seq profiling, a growing number of studies demonstrate that ncRNAs, including long non-coding RNA (lncRNAs) and microRNAs (miRNA), play central roles in progenitor B-cell acute lymphoblastic leukemia (B-ALL) pathogenesis. Furthermore, due to their central roles in cellular homeostasis and their potential as biomarkers, the study of ncRNAs continues to provide new insight into the molecular mechanisms of B-ALL. This article reviews the ncRNA signatures reported for all B-ALL subtypes, focusing on technological developments in transcriptome profiling and recently discovered examples of ncRNAs with biologic and therapeutic relevance in B-ALL.

miR-331-3p is involved in glucocorticoid resistance reversion by rapamycin through suppression of the MAPK signaling pathway

Glucocorticoids (GCs) are commonly used as therapeutic agents for immune-mediated diseases and leukemia. However, considerable inter-individual differences in efficacy have been reported. Several reports indicate that the inhibitor of mTOR rapamycin can reverse GC resistance, but the molecular mechanism involved in this synergistic effect has not been fully defined. In this context, we explored the differential miRNA expression in a GC-resistant CCRF-CEM cell line after treatment with rapamycin alone or in co-treatment with methylprednisolone (MP). The expression analysis identified 70, 99 and 96 miRNAs that were differentially expressed after treatment with MP, rapamycin and their combination compared to non-treated controls, respectively. Two pathways were exclusively altered as a result of the co-treatment: the MAPK and ErbB pathways. We validated the only miRNA upregulated specifically by the co-treatment associated with the MAPK signaling, miR-331-3p. Looking for miR-331-3p targets, MAP2K7, an essential component of the JNK/MAPK pathway, was identified. Interestingly, MAP2K7 expression was downregulated during the co-treatment, causing a decrease in terms of JNK activity. miR-331-3p in mimic-transfected cells led to a significant decrease in MAP2K7 levels and promoted the reversion of GC resistance in vitro. Interestingly, miR-331-3p expression was also associated with GC-resistance in patient leukemia cells taken at diagnosis. The combination of rapamycin with MP restores GC effectiveness through the regulation of different miRNAs, suggesting the important role of these pharmacoepigenetic factors in GC response.

Which long noncoding RNAs and circular RNAs contribute to inflammatory bowel disease?

Inflammatory bowel disease (IBD), a chronic relapsing gastrointestinal inflammatory disease, mainly comprises ulcerative colitis (UC) and Crohn’s disease (CD). Although the mechanisms and pathways of IBD have been widely examined in recent decades, its exact pathogenesis remains unclear. Studies have focused on the discovery of new therapeutic targets and application of precision medicine. Recently, a strong connection between IBD and noncoding RNAs (ncRNAs) has been reported. ncRNAs include microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs). The contributions of lncRNAs and circRNAs in IBD are less well-studied compared with those of miRNAs. However, lncRNAs and circRNAs are likely to drive personalized therapy for IBD. They will enable accurate diagnosis, prognosis, and prediction of therapeutic responses and promote IBD therapy. Herein, we briefly describe the molecular functions of lncRNAs and circRNAs and provide an overview of the current knowledge of the altered expression profiles of lncRNAs and circRNAs in patients with IBD. Further, we discuss how these RNAs are involved in the nosogenesis of IBD and are emerging as biomarkers.

Long non-coding RNA GAS5 inhibits DDP-resistance and tumor progression of epithelial ovarian cancer via GAS5-E2F4-PARP1-MAPK axis

Background

Epithelial ovarian cancer (EOC) is the malignant tumor of the female reproductive system with the highest fatality rate. Tolerance of chemotherapeutic drugs like cisplatin (DDP) occurring in very early stage is one of the important factors of the poor prognosis of epithelial ovarian cancer. Here we aim to study the dysregulation of a particular long noncoding RNA, lncRNA GAS5, and its role in EOC progression.

Methods

The low expression of lncRNA GAS5 in EOC tissues and OC cell lines was determined by microarray analyses and Real-Time qPCR. Flow cytometer assays were used to detect cell cycle and apoptosis of OC cells. CCK8 assay were performed to investigate the DDP sensitivity of OC cells. Western blot was carried out to detect cell growth markers, apoptotic markers, PARP1, E2F4, MAPK pathway protein expression and other protein expression in OC cell lines. The binding of GAS5 and E2F4 were proved by RNA pull-down and RIP assay. The effect of E2F4 on PARP1 were determined by CHIP-qPCR assay and luciferase reporter assay. The effect of lncRNA GAS5 on OC cells was assessed in vitro and in vivo.

Results

By microarray (3 EOC tissues νs. 3 normal ovary tissues) and RT- qPCR (53 EOC tissues νs. 10 normal ovary tissues) we identified lncRNA GAS5 to be dramatically low expressed in EOC samples and correlated with prognosis. Compared with sensitive cell lines, GAS5 was also low expressed in DDP resistant OC cell lines, and over-expression of GAS5 significantly enhanced the sensitivity of OC cells to DDP in vivo and in vitro. Meanwhile the over-expression of GAS5 also caused OC cells G0/G1 arrest and apoptosis increase. Mechanistically, GAS5 might regulate PARP1 expression by recruiting the transcription factor E2F4 to its promoter, and then affect the MAPK pathway activity. Due to the 5’TOP structure, GAS5 could be regulated by transcription inhibitor rapamycin in OC cells.

Conclusion

Here we explored the specific mechanisms of EOC cisplatin resistance and tumor progress due to lncRNA-GAS5, presented the GAS5-E2F4-PARP1-MAPK axis and its role in OC drug-sensitivity and progression for the first time, and the results may provide experimental basis for clinical application.

The expression of GAS5, THRIL, and RMRP lncRNAs is increased in T cells of patients with rheumatoid arthritis

OBJECTIVE

Long non-coding RNAs (lncRNAs) comprise a large and diverse group of non-coding RNAs (ncRNAs) with important regulatory roles in various biological processes, including the immune system regulation. Rheumatoid arthritis (RA) as an autoimmune disease initiates inflammation in the synovial joints. T cells infiltrating into the synovial membrane have an important role in the pathogenesis of RA. The aim of the current investigation was to analyze the expression of four lncRNAs in the T cells from RA patients and healthy controls.

METHODS

In the current study, we investigated the expression of GAS5, RMRP, IFNϒ-AS1, and THRIL lncRNAs in circulating T cells from 20 patients with RA and 18 healthy matched controls by quantitative real-time PCR. T cell isolation was accomplished using the MAC method. We also analyzed the correlation between lncRNA expression and clinical parameters. Also, the mRNA expression levels of IL-17 and TNF-α and the association between lncRNAs and these cytokines were examined.

RESULTS

The results indicate that T cells of RA patients display increased levels of GAS5 (3.31-fold, p = 0.007), RMRP (2.43-fold, p = 0.02), and THRIL (2.14-fold, p = 0.03) lncRNAs compared with those of controls. Furthermore, a positive correlation was found between RMRP expression and disease duration in RA. Receiver operating characteristic (ROC) curve of GAS5, RMRP, and THRIL has a discriminative value in comparing RA patients and controls.

CONCLUSION

The results suggest lncRNAs may be involved in T cell dysfunction in RA. Further studies are required to see whether these lncRNAs have an effect on dysregulation of immune responses in RA disease. Key Points • 70% of non-coding sequences in the human genome are transcribed to RNA. • A growing body of evidence shows the importance of lncRNAs in innate and adaptive immune cell differentiation and functions. • Important recent works suggest a key role of immune cell lncRNAs in autoimmune processes and diseases including RA.

Drug Resistance-Related Competing Interactions of lncRNA and mRNA across 19 Cancer Types

Drug resistance is a common cause of treatment failure in cancer therapy, and molecular mechanisms need further exploration. Competing endogenous RNAs (ceRNAs) can influence drug response by participating in various biological processes, including regulation of cell cycle, signal transduction, and so on. In this study, we systematically explored resistance from the perspective of ceRNA modules. First, we constructed a general ceRNA network, involving 83 long non-coding RNAs (lncRNAs) and 379 mRNAs. Next, we identified the drug resistance-related modules for 138 drugs and 19 cancer types, totaling 758 drug-cancer conditions. Function analysis showed that resistance-related biological processes were enriched in these modules, such as regulation of cell proliferation, DNA damage repair, and so on. Pan-drug and pan-cancer analyses revealed some common and specific modules across multiple drugs or cancers. In addition, we also found that drug pairs with common modules have similar structure, indicating high risk for multidrug resistance (MDR). Finally, we speculated that ceRNA pair GAS5-RPL8 could regulate drug resistance because low expression of GAS5 would enhance microRNA (miRNA)-mediated inhibition of RPL8. In total, we investigated the drug resistance by using ceRNA modules and proposed that ceRNA modules may be new markers for drug resistance that indicated a possible novel mechanism.

Pharmacogenetics of treatments for inflammatory bowel disease

INTRODUCTION

Inflammatory bowel disease is a chronic inflammation of the gut whose pathogenesis is still unclear. Although no curative therapy is currently available, a number of drugs are used in induction and maintenance therapy; however, for most of these drugs, a high inter-individual variability in response is observed. Among the factors of this variability, genetics plays an important role. Areas covered: This review summarizes the results of pharmacogenetic studies, considering the most important drugs used and in particular aminosalycilates, glucocorticoids, thiopurines, monoclonal antibodies and thalidomide. Most studies used a candidate gene approach, even if significant breakthroughs have been obtained recently from applying genome-wide studies. When available, also investigations considering epigenetics and pharmacogenetic dosing guidelines have been included. Expert opinion: Only for thiopurines, genetic markers identified as predictors of efficacy or adverse events have allowed the development of dosing guidelines. For the other drugs, encouraging results are available and great expectations rely on the study of epigenetics and integration with pharmacokinetic information, especially useful for biologics. However, to improve therapy of IBD patients with these drugs, for implementation in the clinics of pharmacogenetics, informatic clinical decision support systems and training about pharmacogenetics of health providers are needed.

Downregulation of serum long noncoding RNA GAS5 may contribute to insulin resistance in PCOS patients

Polycystic ovary syndrome (PCOS) is a common endocrine disease that affects reproductive-aged women and mostly characterized by insulin resistance (IR). The underlying mechanism remains unknown. Long noncoding RNAs (lncRNAs) have been demonstrated to be involved in various levels of biological regulation process of cell development, metabolism, and differentiation. This study aims to investigate the relationship between IR and differential expression of lncRNA Growth-arrest specific transcript 5 (GAS5) in patients' serum with and without PCOS. A total of 76 cases of serum was collected from non-PCOS and PCOS patients with and without IR to measure interleukin-18 (IL-18) and GAS5 expression, which were correlated with IR status. The IL-18 concentration in serums was significantly increased in PCOS patients with IR. GAS5 expression was decreased in serums in PCOS patients with IR. Result of correlation analysis shows that there is a negative association between GAS5 expression and homeostasis model of assessment for insulin resistance (HOMA-IR). GAS5 was yielded the ROC curve (AUC). Our study implied that elevated IL-18 expression and downregulation of GAS5 in serums might contribute to IR in PCOS patients.

Down-regulation of lncRNA, GAS5 decreases chemotherapeutic effect of dendrosomal curcumin (DNC) in breast cancer cells

BACKGROUND

Despite positive results obtained from anticancer activities of curcumin, there are some obstacles that limit its use as an anticancer agent.

HYPOTHESIS/PURPOSE

Different methods such as employing the dendrosomal curcumin (DNC) were examined to overcome such problems. There is increasing evidence representing long non-coding RNAs play important roles in biological processes. In this study, we focused on the roles of GAS5 in the anti-cancer effects of DNC on breast cancer.

METHODS

We used several methods including MTT assay, apoptosis assay, cell cycle analysis, transwell migration assay and RT-PCR.

RESULTS

We observed a significant increase in the expression of Tusc7, and GAS5 genes with DNC treatment of MCF7, MDA-MB231, and SKBR3 cells. Also, the combination of GAS5 down-regulation and DNC treatment showed lower percentages of apoptotic cells and a higher level of penetration through the membrane compared with DNC treatment alone. Furthermore, DNC induced a significant increase in the number of cells in sub G1/G1 phase and a decrease in the G2/M phase of the cell cycle. But, after GAS5 down-regulation alone opposite results was observed compared to DNC.

CONCLUSION

We observed that GAS5 down-regulation can suppress many aspects of DNC anti-cancer effects in breast cancer cells, it seems that co-treatment with DNC and GAS5 over-expression may provide a clinically useful tool for drug-resistance breast cancer cells.

Association of long non-coding RNA GAS5 and miR-21 levels in CD4+ T cells with clinical features of systemic lupus erythematosus

The present study aimed to assess the expression of growth arrest-specific 5 (GAS5) and microRNA (miR)-21 in systemic lupus erythematosus (SLE), and attempted to explore their association with clinical features. CD4⁺ T cells were isolated from peripheral blood of healthy donors and SLE patients by magnetic-activated cell sorting. GAS5 and miR-21 expression levels in cluster of differentiation (CD)4⁺ T cells were measured by reverse-transcription quantitative polymerase chain reaction. The results revealed that GAS5 and miR-21 levels were significantly elevated in CD4⁺ T cells of patients with SLE compared with those in control subjects (P<0.05). Regarding clinical features, SLE patients with ulceration had higher GAS5 expression levels in CD4⁺ T cells than those without ulceration (P<0.05), and the expression of miR-21 was significantly higher in CD4⁺ T cells of SLE patients with low levels of complement component 3 (C3) than in those with normal levels of complement C3 (P<0.05). In conclusion, GAS5 and miR-21 in CD4⁺ T cells may serve as potential biomarkers for the diagnosis and monitoring of the progression of SLE.

Role of the Long Non-Coding RNA Growth Arrest-Specific 5 in Glucocorticoid Response in Children with Inflammatory Bowel Disease

Glucocorticoids (GCs) are widely employed in inflammatory, autoimmune and neoplastic diseases, and, despite the introduction of novel therapies, remain the first-line treatment for inducing remission in inflammatory bowel disease (IBD). Given the high incidence of suboptimal response, associated with a significant number of side-effects, that are particularly severe in paediatric patients, the identification of subjects that are most likely to respond poorly to GCs is extremely important. Recent evidence suggests that the long non-coding RNA (lncRNA) GAS5 could be a potential marker of GC resistance. To address this issue, we evaluated the association between the lncRNA GAS5 and the efficacy of steroids, in terms of inhibition of proliferation, in two cell lines derived from colon and ovarian cancers, to confirm the sensitivity and specificity of these lncRNAs. These cells showed a different sensitivity to GCs and revealed differential expression of GAS5 after treatment. GAS5 was up-regulated in GC-resistant cells and accumulated more in the cytoplasm compared to the nucleus in response to the drug. The functions of GAS5 were assessed by silencing, and we found that GAS5 knock-down reduced the proliferation during GC treatment. Furthermore, for the first time, we measured GAS5 levels in 19 paediatric IBD patients at diagnosis and after the first cycle of GCs, and we demonstrated an up-regulation of the lncRNA in patients with unfavourable steroid response. Our preliminary results indicate that GAS5 could be considered a novel pharmacogenomic marker useful for the personalization of GC therapy.