Expression Levels Of XIST Research Articles

Circulating long noncoding RNA, Zfpm2-As1, and XIST based on medical data analysis are potential plasma biomarkers for gastric cancer diagnosis.

Long noncoding RNAs (lncRNAs) participate in diseases, especially tumorigenesis, including gastric cancer (GC). Although lncRNAs in GC tissues have been extensively studied in previous research, the possible significance of circulating lncRNAs in diagnosing GC is still unknown. The present work investigated lncRNAs ZFPM2-AS1 and XIST with high expression in GC tissues proved as potential plasma biomarkers from 20 early GC cases, 100 GC cases, and 90 normal subjects. The possible correlation between ZFPM2-AS1 and XIST expression levels was analyzed with general characteristics and clinicopathological features. The performance in diagnosis was assessed according to receiver operating characteristic (ROC) analysis. According to the results, XIST and ZFPM2-AS1 expression remarkably increased within GC plasma relative to normal subjects (P< 0.01); besides, lncRNA XIST expression after surgery had a tendency of downregulation compared with preoperative levels (P< 0.05). Moreover, the area under ROC curve (AUC) values were 0.62 for ZFPM2-AS1 and 0.68 for XIST, while the pooled AUC value of CA-724 and two lncRNAs was 0.751. Circulating lncRNAs ZFPM2-AS1 and XIST can serve as the candidate plasma biomarkers used to diagnose GC.

Dysregulation of the Long Noncoding RNA X-Inactive–Specific Transcript Expression in Male Patients with Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a sex-biased disease with female gender as a significant risk factor. Recently, we reported that increased expression of the long non-coding (lnc)RNA Xist, as induced by an intersectin-1s protein fragment with proliferative potential (EHITSN), may explain the sexual dimorphism of female pulmonary artery endothelial cells (ECs) and at least in part, the imbalance sex/ratio of PAH.Xist is essential for X-chromosome inactivation and dosage compensation of X-linked genes. Increased Xist expression was also detected in a subset of ECs and lung tissue samples of male PAH patients. The role of different Xist expression levels in ECs of male PAH patients (ECPAH) was studied in several lines of male ECPAH in conjunction with molecular, biochemical, morphological, and functional approaches. Male ECPAH showed on average 10.3-fold increase in high Xist vs. low Xist, a significant association between Xist levels and their proliferative potential, and a heterogeneous methylation of the Xist/Tsix locus. Interestingly, Xist up-regulation in male ECPAH decreases the expression of Klf2, via EHITSN interaction with EZH2, the catalytic subunit of the polycomb repressive complex 2. Moreover, the studies demonstrate that EHITSN-triggered p38/Elk1/c-Fos signaling is a pathological mechanism central to ECPAH proliferation and the dynamic crosstalk with cell cycle regulatory proteins ccna1/ccnd2, and Xist-EZH2-Klf2 interaction participate directly and differentially in establishing the proliferative profile of male ECPAH.

Analyzing the expression pattern of the noncoding RNAs (HOTAIR, PVT-1, XIST, H19, and miRNA-34a) in PBMC samples of patients with COVID-19, according to the disease severity in Iran during 2022-2023: A cross-sectional study.

MicroRNAs (miRNAs) and long noncoding RNAs (lncRNAs) are well-known types of noncoding RNAs (ncRNAs), which have been known as the key regulators of gene expression. They can play critical roles in viral infection by regulating the host immune response and interacting with genes in the viral genome. In this regard, ncRNAs can be employed as biomarkers for viral diseases. The current study aimed to evaluate peripheral blood mononuclear cell (PBMC) ncRNAs (lncRNAs-homeobox C antisense intergenic RNA [HOTAIR], -H19, X-inactive-specific transcript [XIST], plasmacytoma variant translocation 1 [PVT-1],and miR-34a) as diagnostic biomarkers to differentiate severe COVID-19 cases from mild ones. Candidate ncRNAs were selected according to previous studies and assessed by real-time polymerase chain reaction in the PBMC samples of patients with severe coronavirus disease 2019 (COVID-19)(n = 40), healthy subjects (n = 40), and mild COVID-19 cases (n = 40). Furthermore, the diagnostic value of the selected ncRNAs was assessed by analyzing the receiver-operating characteristic (ROC). The results demonstrated that the expression pattern of the selected ncRNAs was significantly different between the studied groups. The levels of HOTAIR, XIST, and miR-34a were remarkably overexpressed in the severe COVID-19 group in comparison with the mild COVID-19 group, and in return, the PVT-1 levels were lower than in the mild COVID-19 group. Interestingly, the XIST expression level in men with severe COVID-19 was higher compared to women with mild COVID-19. ROC results suggested that HOTAIR and PVT-1 could serve as useful biomarkers for screening mild COVID-19 from severe COVID-19. Overall, different expression patterns of the selected ncRNAs and ROC curve results revealed that these factors can contribute to COVID-19 pathogenicity and can be considered diagnostic markers of COVID-19 severe outcomes.

Association of XIST/miRNA155/Gab2/TAK1 cascade with the pathogenesis of anti-phospholipid syndrome and its effect on cell adhesion molecules and inflammatory mediators.

Anti-phospholipid syndrome (APS) is an autoimmune disease characterized by thrombosis and miscarriage events. Still, the molecular mechanisms underlying APS, which predisposes to a wide spectrum of complications, are being explored. Seventy patients with primary and secondary APS were recruited, in addition to 35 healthy subjects. Among APS groups, the gene expression levels of XIST, Gab2, and TAK1 were higher along with declined miRNA155 level compared with controls. Moreover, the sera levels of ICAM-1, VCAM-1, IL-1ꞵ, and TNF-α were highly elevated among APS groups either primary or secondary compared with controls. The lncRNA XIST was directly correlated with Gab2, TAK1, VCAM-1, ICAM-1, IL-1ꞵ, and TNF-α. The miRNA155 was inversely correlated with XIST, Gab2, and TAK1. Moreover, ROC curve analyses subscribed the predictive power of the lncRNA XIST and miRNA155, to differentiate between primary and secondary APS from control subjects. The lncRNA XIST and miRNA155 are the upstream regulators of the Gab2/TAK1 axis among APS patients via influencing the levels of VCAM-1, ICAM-1, IL1ꞵ, and TNF-α which propagates further inflammatory and immunological streams. Interestingly, the study addressed that XIST and miRNA155 may be responsible for the thrombotic and miscarriage events associated with APS and provides new noninvasive molecular biomarkers for diagnosing the disease and tracking its progression.

LncRNA XIST Inhibits Gastric Cancer Progression Through the Wnt Pathway by Regulating the miR-30a-5p/SOX9 Axis

We aimed to investigate the impact of XIST on the pathogenesis of gastric cancer (GC). We used quantitative real-time polymerase chain reaction (RT-qPCR) to determine the expression levels of XIST, SOX9, and miR-30a-5p in GC cells. Western blot assay was used to measure the protein levels of SOX9, β-catenin, and c-Myc. We also performed MTT and transwell assays to assess proliferation, apoptosis, and invasion. Dual-luciferase reporter assays and RNA immunoprecipitation (RIP) assays were used to confirm the interaction between miR-30a-5p and XIST or SOX9. We found that GC tumor cells express high levels of XIST and SOX9, which promote cell proliferation, invasion, and resistance to apoptosis. Specifically, we observed that XIST acts as a sponge for miR-30a-5p in GC cell line SGC-7901, while miR-30a-5p targets SOX9. SOX9 expression is regulated by XIST via miR-30a-5p acting as a competitive endogenous RNA. Furthermore, we identified a miR-30a-5p/SOX9 axis that modulates the Wnt/β-catenin signaling pathway. In conclusion, our study demonstrates that LncXIST interacts with miR-30a-5p as a competitive endogenous RNA to promote GC cell proliferation, migration, invasion, and inhibition of apoptosis through the regulation of SOX9 expression.

Identification and functional analysis of LncRNA-XIST ceRNA network in prostate cancer

BackgroundLong non-coding RNAs (lncRNAs) play a functional role in the progression of prostate cancer (PCa). However, the molecular mechanism, expression, or function of the lncRNA XIST in PCa is not well understood. Therefore, the major goal of this study was to investigate the involvement of XIST in PCa.MethodsWe used the The Cancer Genome Atlas (TCGA) database to conduct a pan-cancer bioinformatics analysis of XIST and identified that it may play an important role in prostate cancer. This finding was verified using clinical samples and in vitro assays. Finally, we constructed an XIST ceRNA network for prostate cancer.ResultsOur in vitro and in vivo results showed that the XIST gene expression level was higher in PCa derived cells and tissues compared to that in normal cells and tissues. XIST gene expression level was positively correlated with the invasion and proliferation of tumour cells. Furthermore, the downregulation of XIST inhibited the growth of subcutaneous 22Rv1 xenografts in nude mice. In addition, we constructed a XIST ceRNA network. Consistent with previous studies, we found that the role of XIST is mediated through via sponges, such as miRNA -96-5p, miRNA -153-3p, and miRNA-182-5p.ConclusionHigh expression level of XIST can lead to enhanced carcinogenicity in PCa. Therefore, XIST has the potential to be used as a prognostic marker and may become a new research focus for the treatment of PCa.

A novel lncRNA-miRNA-mRNA triple network identifies lncRNA XIST as a biomarker for acute myocardial infarction.

Despite the well-established role of long non-coding RNAs (lncRNAs) across various biological processes, their mechanisms in acute myocardial infarction (AMI) are not fully elucidated. The GSE34198 dataset from the Gene Expression Omnibus (GEO) database, which comprised 49 specimens from individuals with AMI and 47 specimens from controls, was extracted and analysed using the weighted gene co-expression network analysis (WGCNA) package. Twenty-seven key genes were identified through a combination of the degree and gene significance (GS) values, and the CDC42 (degree = 64), JAK2 (degree = 41), and CHUK (degree = 30) genes were identified as having the top three-degree values among the 27 genes. Potential interactions between lncRNA, miRNAs and mRNAs were predicted using the starBase V3.0 database, and a lncRNA-miRNA-mRNA triple network containing the lncRNA XIST, twenty-one miRNAs and three hub genes (CDC42, JAK2 and CHUK) was identified. RT–qPCR validation showed that the expression of the JAK2 and CDC42 genes and the lncRNA XIST was noticeably increased in samples from patients with AMI compared to normal samples. Pearson’s correlation analysis also proved that JAK2 and CDC42 expression levels correlated positively with lncRNA XIST expression levels. The area under ROC curve (AUC) of lncRNA XIST was 0.886, and the diagnostic efficacy of the lncRNA XIST was significantly better than that of JAK2 and CDC42. The results suggested that the lncRNA XIST appears to be a risk factor for AMI likely through its ability to regulate JAK2 and CDC42 gene expressions, and it is expected to be a novel and reliable biomarker for the diagnosis of AMI.

YY1-induced lncRNA XIST inhibits cartilage differentiation of BMSCs by binding with TAF15 to stabilizing FUT1 expression.

IntroductionThe functional roles and mechanism of the XIST in osteoarthritis and the chondrogenic differentiation of BMSCs were clarified.MethodsThe expression levels of XIST, TAF15, FUT1 and YY1 were detected through quantitative RT-PCR. The protein expression of Sox9, ACAN, COL2A1 and FUT1 were detected by western blot and immunohistochemistry. The damage of cartilage tissue was detected by HE staining, and Safranin O-fast green. Alcian-Blue and Alizarin red S staining were performed to evaluate BMSCs chondrogenic differentiation. The relationship between XIST and TAF15, XIST and TAF15 were analyzed by RNA immunoprecipitation assay. Luciferase reporter assays and chromatin immunoprecipitation were performed to detect the interaction relationship between XIST and YY1. In addition, osteoarthritis mice were built to assess the function of XIST in vivo.ResultsThe levels of XIST, TAF15 and FUT1 were upregulated in cartilage tissues from osteoarthritis patient. The level of XIST was decreased in BMSCs during chondrogenic differentiation. XIST overexpression inhibited the chondrogenic differentiation of BMSCs. Moreover, silencing of FUT1 reversed the effects of XIST overexpression on BMSCs chondrogenic differentiation. Mechanistically, in BMSCs, YY1 induced the expression of XIST in BMSCs, and XIST regulated FUT1 mRNA stability through targeting TAF15. Furthermore, silencing of XIST alleviated the symptoms of cartilage injury in OA mice.ConclusionTaken together, these results suggested that YY1 induced XIST was closely related to the chondrogenic differentiation of BMSCs and the progression of osteoarthritis by TAF15/FUT1 axis, and may be a new OA therapeutic target.

Abstract P4-02-09: The lncRNA XIST mediates sensitivity to ERβ targeted therapies in triple negative breast cancer

Abstract Background:. Poor patient outcomes in triple negative breast cancer (TNBC) largely stem from a lack of understanding of therapeutic vulnerabilities and an insufficient armamentarium of effective drugs. The standard of care for most early stage TNBC patients continues to be (neo)adjuvant chemotherapy and radiation. Identifying additional therapeutic options for this subset of patients represents a major unmet need. We and others demonstrated that estrogen receptor beta (ERβ) is expressed in about 20% of TN tumors. Prior research has shown that ligand-mediated activation of ERβ decreases proliferation, invasion, and migration in TNBC cell lines. In vivo, ERβ suppresses the growth of cell line xenograft models and prevents the development of metastatic lesions in a ligand dependent manner. Mechanistically, we found that ERβ repurposes EZH2 to suppress oncogenic NFκB signaling and that pharmacologic inhibition of EZH2 diminishes ERβ function and its anti-cancer effects. This research has led to an ongoing clinical trial (NCT03941730) assessing the efficacy of estradiol in ERβ+ TNBC patients with chemorefractory disease. As with all therapies, patients will exhibit de novo and acquired resistance and therefore we sought to understand the mechanisms of resistance to ERβ targeted therapies. Methods:. Using multiple models of ERβ positive TNBC, we developed ERβ resistant cell lines through chronic exposure to estradiol and the ERβ specific agonist LY500307 over a period of 8 months. We employed RNA sequencing to characterize the transcriptomic changes which occurred following ERβ resistance. We profiled XIST expression across multiple publicly available datasets, including TCGA, Metabric, BEAUTY, and GTEx. XIST expression was also modulated using CRISPR/Cas9 to assess subsequent effects on TNBC cell biology, ERβ function, and response to ERβ targeted therapies. Results:. Our resistant cell line models of ERβ positive TNBC maintained ERβ expression, but were no longer growth inhibited by ERβ agonists. RNAseq revealed substantial differences comparing the transcriptome of resistant versus sensitive cell lines, of which the most increased transcript in the resistant setting was the lncRNA XIST. XIST is best known for its role in X-chromosome inactivation through recruitment and association with the PRC2 complex, and thus EZH2. However, little is known about its functions in breast cancer. We therefore assessed the expression levels of XIST in breast tumors and cell lines. XIST expression was highly variable in breast cancer, was found in a proportion of all breast cancer sub-types and did not correlate with ERβ status. However, XIST expression was up-regulated in ERβ expressing cell lines following long term estrogen treatment. No effects on XIST expression were identified in multiple ERα positive models following estrogen, SERM/SERD treatment, or estrogen deprivation. Furthermore, upregulation of XIST was not associated with resistance to Paclitaxel or Doxorubicin, suggesting XIST is not a part of a broad resistance phenotype. Strikingly, CRISPR mediated knockout of XIST in ERβ resistant cells completely re-sensitized cells to ERβ targeted therapies suggesting that XIST expression is a critical component of ERβ resistance. Conclusions:. ERβ represents a relevant therapeutic target that is being tested in clinical trials. Using multiple in vitro models, we provide evidence that XIST expression is sufficient to induce resistance to. ERβ targeted therapies in TNBC and may therefore represent a relevant biomarker for patient stratification. Further strategies to suppress XIST expression may elicit anti-cancer effects on their own and may resensitize a sub-set of ERβ resistant tumors to ERβ agonists. Citation Format: Michael J Emch, Kirsten GM Aspros, Elizabeth S Bruinsma, Krishna R Kalari, Calley J Jones, Brandon W Simone, Matthew P Goetz, John R Hawse. The lncRNA XIST mediates sensitivity to ERβ targeted therapies in triple negative breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-02-09.

Involvement of N6-methyladenosine modifications of long noncoding RNAs in systemic lupus erythematosus

BackgroundLncRNAs are potential biomarkers for SLE, but the epigenetic regulatory mechanisms of N6-methyladenosine (m6A) modification in SLE remain largely unclear. MethodsIn this study, we established m6A modification profile and investigated the potential roles of m6A-related lncRNAs in SLE. The m6A modification profile of SLE was established using MeRIP-seq. Four potential m6A related-lncRNAs (linc02446, linc01410, Xist, and PSMB8-AS1) were selected for validation using qRT-PCR, and their expression and association with clinical characteristics with SLE were evaluated. ResultsOverall, m6A level was lower in patients with SLE than in controls. Compared with controls, the expression of the two m6A related-lncRNAs (Xist and PSMB8-AS1) was downregulated in patients with SLE (all P < 0.05); the linc02446 was up-regulated in PBMCs of patients with SLE (Z=-2.738, P = 0.006), while it was not differentially expressed in T cells (Z=-0.387, P = 0.699). No significant alteration in linc01410 expression was observed in patients (Z=-0.940, P = 0.347). The lower expression levels of Xist and PSMB8-AS1 were associated with many clinical manifestations in patients with SLE (all P < 0.05). Additionally, mRNAs co-expressed with m6A related-lncRNAs (Xist, linc02446, and PSMB8-AS1) also participated in SLE. ConclusionThese results suggest that m6A methylation and m6A related-lncRNAs might be involved in the pathogenesis of SLE. Thus, our findings provide some clues on the potential function of lncRNAs that m6A modification may target in novel therapeutic or diagnostic strategies for SLE.

Zinc Promotes Microglial Autophagy Through NLRP3 Inflammasome Inactivation via XIST/miR-374a-5p Axis in Spinal Cord Injury.

Zinc has reported to play a neuroprotective role in the development of spinal cord injury (SCI). The protective mechanism of zinc remains to be uncovered. The aim of the current study was to investigate the neuroprotective mechanism of zinc in the progression of SCI. The C57BL/6J mouse SCI model was established to confirm the protective role of zinc in vivo, while the cellular model was induced in mouse microglial BV2 cells by using lipopolysaccharide (LPS). The expression levels of XIST, miR-374a-5p and NLRP3 inflammasome as well as the autophagy-related proteins were detected using real-time PCR and immunoblotting. Cell viability was assessed by CCK-8 assay. Apoptosis was evaluated by TUNEL staining, flow cytometry, the determination of apoptosis-related proteins. The target relationship was confirmed by luciferase reporter assays. Zinc improved locomotor function in SCI mice and alleviated LPS-induced BV2 cell injuries by inhibiting apoptosis and initiating autophagy processes. XIST and NLRP3 inflammasome was upregulated while miR-374a-5p was downregulated in spinal cords of SCI mice and LPS-treated BV2 cells. All these effects were inhibited by Zinc treatment. XIST knockdown triggered microglial autophagy-mediated NLRP3 inactivation in LPS-induced BV2 cells by regulating miR-374a-5p. Zinc treatment protected BV2 cells from LPS-induced cell injury by the downregulation of XIST. This process might be through autophagy‑mediated NLRP3 inflammasome inactivation by targeting miR-374a-5p. Zinc downregulates XIST and induces neuroprotective effects against SCI by promoting microglial autophagy-induced NLRP3 inflammasome inactivation through regulating miR-374a-5p. Our finding provides novel opportunities for the understanding of zinc-related therapy of SCI.

LncRNA XIST is involved in rheumatoid arthritis fibroblast-like synoviocytes by sponging miR-126-3p via the NF-κB pathway

The role and mechanism of lncRNA XIST (XIST) in the development of rheumatoid arthritis (RA) was explored in this study. RT-qPCRs were performed to detect the expression of XIST and miR-126-3p in synovial tissues and cells. Target gene prediction and luciferase gene reporter assay were used to validate downstream target genes of XIST. MTT assay, EdU staining and Annexin V/PI staining were performed to explore the effects of XIST and miR-126-3p on cell proliferation and apoptosis. Western blotting analysis was used to detect the expression of related proteins. We found that the expression levels of XIST in tissues and cells were significantly higher than that in normal tissues and cells. Down-regulation of XIST could inhibit cell proliferation rate and increase apoptosis rate. Luciferase gene reporter assay showed that miR-126-3p was a downstream target gene of XIST. Overexpression of miR-126-3p significantly inhibited RA-FLS cell proliferation and induced RA-FLS cell apoptosis. In addition, down-regulation of XIST could increase the ratio of caspase-3 and Bax/Bcl-2. In addition, overexpression of miR-126-3p could inhibit the NF-κB signalling pathway by reducing the expression levels of p-p65 and p-IκBα in RA-FLS cells. In conclusion, down-regulation of XIST can inhibit the proliferation of synovial fibroblasts by increasing the expression levels of miR-126-3p/NF-κB, thereby inhibiting the occurrence and development of RA.

THE STUDY OFLONG NON-CODING RNAs(NAALADL2 AND XIST) GENEEXPRESSION IN DIFFUSE LARGE B CELL LYMPHOMA

Diffuse large B cell lymphoma (DLBCL) is the most predominant type of Non Hodgkin- Lymphomas, representing more than one third of all recently diagnosed cases. Long non-coding RNAs (lncRNAs) are a class of RNA not coding for protein having more than 200 nucleotides and have significant roles in tumor formation and they have been investigated in different types of solid and hematologic tumors, including DLBCL.This work aims to study the level of lncRNAs(NAALADL2 and XIST)gene expression in DLBCL.NAALADL2 and XIST gene expression levels in blood were performed by real time qPCR technique. Forty five DLBCL patients and forty five age and gender matched healthy controls were included in this study.There was significant statistical increase in the expression of NAALADL2 and decrease of XIST expression in patients compared to control group (p value 10.3 and<1.57 for NAALADL2 and XISTrespectively.There was significant positive correlation between NAALADL2 and advanced stage and a significant negative correlation is found between XIST and advanced stage. It may be concluded that NAALADL2 and XISTexpression levels were obviously associated with DLBCL and might determine the disease progression.

LncRNA XIST Inhibits the Progression of Oral Squamous Cell Carcinoma via Sponging miR-455-3p/BTG2 Axis.

ObjectiveOral squamous cell carcinoma (OSCC) is one of the most common cancers, accounting for over 90% of malignant lesions in the oral cavity. Long non-coding RNAs play an important role in the development of OSCC. This study aimed to investigate the effects of lncRNA XIST on the malignant behaviors of OSCC cells and its possible molecular mechanisms.MethodsReal-time quantitative PCR and Western blot were used to detect the RNA and protein level, respectively. CAL27 and SCC25 cells with the lowest expression level of XIST were used for further study. MTT, transwell assay, colony formation, and xenograft model were applied to examine the effect of XIST on the progression of OSCC. FISH assay was performed to investigate the co-location of XIST and miR-455-3p in OSCC cells. The bioinformatics analysis, luciferase, and RNA pull down assay were utilized to predict and verify the target genes of miR-455-3p.ResultsXIST was downregulated in OSCC tissues and cell lines. Overexpression of XIST inhibited the proliferation, migration, and invasion ability of OSCC cells. Bioinformatics analysis and luciferase reporter assay confirmed XIST could bind to miR-455-3p. Besides, miR-455-3p directly targeted BTG2 in OSCC cells. Rescue experiments further confirmed the positive interaction between miR-455-3p and XIST as well as between miR-455-3p and BTG2.ConclusionXIST was down-regulated in OSCC. XIST regulated the expression of BTG2 via sponging miR-455-3p. XIST/miR-455-3p/BTG2 signal axis inhibited the malignant progression of OSCC.

LncRNA XIST promotes migration of Wilms' tumor cells through modulation of microRNA-193a-5p.

The aim of this study was to investigate long non-coding RNA (lncRNA) XIST expression in Wilms' tumor (WT) and to further explore its relationship with clinical features and prognosis of WT patients. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was carried out to examine the expression level of XIST in tumor tissue samples and paracancerous ones collected from 43 patients with renal cell carcinoma, and the interplay between XIST expression and clinical indicators, as well as prognosis of patients was analyzed. Meanwhile, XIST level in the nephroblast cancer cell line was further confirmed by qRT-PCR. In addition, XIST knockdown model was constructed using lentivirus in the WT cell lines, including HFWT and 17-94, and the influence of XIST on WT cell functions was analyzed through transwell assay. Finally, we investigated whether lncRNA XIST plays a role in the progression of WT by modulating microRNA-193a-5p. In this research, qRT-PCR results revealed a significantly higher expression of lncRNA XIST in tumor tissue specimens of patients with renal cell carcinoma than that in adjacent ones. Compared with patients with low expression of lncRNA XIST, those with high XIST expression had a higher incidence of distant metastasis and a lower overall survival rate. Compared with the negative control group, the metastatic ability of WT cells in the lncRNA XIST knockdown group was markedly weakened. In addition, the results of qPCR showed that mRNA expression of lncRNA XIST and microRNA-193a-5p were negatively correlated in renal cell carcinoma tissue specimens. At the same time, silencing microRNA-193a-5p reversed the reduced metastasis ability of WT cells induced by knockdown of XIST. LncRNA XIST expression is dramatically enhanced in WT tissues and cell lines, which is closely associated with the incidence of distant metastasis and patients' poor prognosis. In addition, we demonstrated that lncRNA XIST may accelerate the malignant progression of WT via inhibiting microRNA-193a-5p.

XIST lost induces ovarian cancer stem cells to acquire taxol resistance via a KMT2C-dependent way

Background/aimsThe expression levels of long non-coding RNA XIST are significantly associated with paclitaxel (Pac) sensitivity in ovarian cancer, but the mechanism of action remains unclear. Therefore, this experimental design was based on lncRNA XIST analysis to regulate the effect of XIST on the tumor stem cell and paclitaxel sensitivity in ovarian cancer.MethodsSphere assay and fluorescence activated cell sorting (FACS) were used to determine the expression levels of XIST and sensitivity to paclitaxel treatment. The effect of the proliferation was detected by MTT assay. Target gene prediction and screening, luciferase reporter assays were used to validate downstream target genes for lncRNA XIS and KMT2C. The expression of KMT2C was detected by RT-qPCR and Western blotting. RT-qPCR was used to detect the expression of cancer stem cell-associated genes SOX2, OCT4 and Nanog. The tumor changes in mice were detected by in vivo experiments in nude mice.ResultsThere was an inverse correlation between the expression of XIST and cancer stem cell (CD44 + /CD24−) population. XIST promoted methylation of histone H3 methylation at lysine 4 by enhancing the stability of lysine (K)-specific methyltransferase 2C (KMT2C) mRNA. XIST acted on the stability of KMT2C mRNA by directly targeting miR-93-5p. Overexpression of miR-93-5p can reverse the XIST overexpression-induced KMT2C decrease and sphere number increase. Overexpression of KMT2C inhibited XIST silencing-induced proliferation of cancer stem cells, and KMT2C was able to mediate paclitaxel resistance induced by XIST in ovarian cancer. The study found that XIST can affect the expression of KMT2C in the ovarian cancer via targeting miR-93-5p.ConclusionXIST promoted the sensitivity of ovarian cancer stem cells to paclitaxel in a KMT2C-dependent manner.

Variation in the expression level of MALAT1, MIAT and XIST lncRNAs in coronary artery disease patients with and without type 2 diabetes mellitus

Background: The MALAT1, MIAT, and XIST long noncoding RNAs (lncRNAs) participate in the pathogenesis of complex diseases and also serve as diagnostic markers. The study aimed to assess their expressions in CAD patients with or without T2DM against diabetic and non-diabetic controls.Methods: The expression levels of three lncRNAs in 50 CAD patients (with or without diabetes) and 50 non-CAD subjects (with or without diabetes) were evaluated by using the TaqMan Assay method.Results: MALAT1 and MIAT were upregulated in CAD patients (p Value= .0008 and .0078, respectively). The expression level of XIST was significantly elevated diabetic compared to non-diabetic CAD patients (p Value= .0003). MALAT1 gene had the highest diagnostic power for discrimination of CAD patients from controls (AUC= 0.682, p Value=.001).Conclusions: The current study supports the participation of lncRNAs in the pathogenesis of CAD and T2DM and highlights their potential as diagnostic biomarkers.

Expression of serum lncRNA-Xist in patients with polycystic ovary syndrome and its relationship with pregnancy outcome

ObjectiveLong non-coding RNA X-inactive specific transcript (LncRNA Xist) plays a pivotal role in various types of human diseases, while its involvement in polycystic ovary syndrome (PCOS) remains unknown. In the study we aimed to investigate if downregulate Xist expression is involved in PCOS and is correlated with adverse pregnant outcomes in PCOS. Materials and methodsIn this study, expression of lncRNA Xist in peripheral blood collected from both PCOS patients and controls were detected by qRT-PCR. Diagnostic values of Xist expression for PCOS were evaluated by ROC curve analysis. Correlation between Xist expression and pregnant outcomes of PCOS patients was analyzed. ResultsCompared with controls, Xist was significantly downregulated in patients with PCOS but not in patients with other types of diseases. Xist expression can be used to effectively distinguish PCOS patients from controls. Reduced expression level of Xist was significantly correlated with adverse pregnant outcomes of PCOS patients but not healthy controls. ConclusionThe downregulation of Xist expression may be involved in PCOS and is correlated with adverse pregnant outcomes in PCOS.

Long non-coding RNA XIST promotes hepatocellular carcinoma progression by sponging miR-200b-3p.

Recent studies have proved that long noncoding RNAs (lncRNAs) act as an important role in many diseases. In this research, lncRNA XIST was explored to identify how it functions in the development of hepatocellular carcinoma (HCC). Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was utilized to detect XIST expression in HCC patients. Then, we conducted Cell Counting Kit-8 (CCK-8) assay and colony formation assays in vitro. Furthermore, mechanism assays and the interaction between XIST and miR-200b-3p were conducted. By comparing with XIST expression in adjacent tissues, the XIST expression level was significantly higher in HCC samples. Moreover, functional assays showed that the cell growth ability of HCC cells was inhibited after XIST was silenced in vitro, and tumor formation was inhibited after XIST was silenced in vivo. Further experiments showed that miR-200b-3p was directly targeted by XIST. Above results suggest that XIST could enhance the cell growth ability of HCC by targeting miR-200b-3p, which suggest that XIST may be a potential therapeutic target in HCC.

Downregulation of long non-coding RNA XIST inhibits cell proliferation, migration, invasion and EMT by regulating miR-212-3p/CBLL1 axis in non-small cell lung cancer cells.

Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors in the world and its 5-year survival rate is very low. Long non-coding RNA X-inactive specific transcript (lncRNA XIST) has been demonstrated to play vital roles in NSCLC, but the exact molecular mechanisms underlying NSCLC still need to be further explored. Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) was performed to detect the expression of XIST, miR-212-3p and Casitas B-lineage proto-oncogene like 1 (CBLL1). Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted to analyze the relationship among XIST, miR-212-3p and CBLL1. Cell Counting Kit-8 (CCK-8) assay and transwell invasion assay were carried out to evaluate cell proliferation, migration and invasion, respectively. Western blot analysis was conducted to examine the protein expression of CBLL1, E-cadherin, N-cadherin and Vimentin. Murine xenograft assay was conducted to explore the role of XIST in vivo. Expression levels of XIST and CBLL1 were markedly upregulated, while the miR-212-3p level was markedly downregulated in NSCLC tissues and cells. MiR-212-3p was identified as a direct target of XIST, and miR-212-3p was predicted to target CBLL1. XIST knockdown repressed NSCLC cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro, and suppressed tumor growth in vivo, while miR-212-3p inhibition restored the effects. Furthermore, CBLL1 overexpression could abolish the effects of miR-212-3p overexpression on NSCLC cell proliferation, migration, invasion and EMT in vitro. XIST was significantly decreased in NSCLC tissues and cells, and XIST knockdown suppressed the proliferation, migration, invasion and EMT of NSCLC cells by miR-212-3p/CBLL1 axis. These findings facilitated our understanding of lncRNA regulation in NSCLC.