Characterization of N6-methyladenosine long non-coding RNAs in sporadic congenital cataract and age-related cataract

AIM:To characterize the N6-methyladenosine(m6A)modification patterns in long non-coding RNAs(lncRNAs)in sporadic congenital cataract(CC)and age-related cataract(ARC).METHODS:Anterior capsule of the lens were collected from patients with CC and ARC.Methylated RNA immunoprecipitation with next-generation sequencing and RNA sequencing were performed to identify m6A-tagged lncRNAs and lncRNAs expression.Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses and Gene Ontology annotation were used to predict potential functions of the m6A-lncRNAs.RESULTS:Large amount of m6A peaks within lncRNA were identified for both CC and ARC,while the level was much higher in ARC(49870 peaks)than that in CC(18688 peaks),yet those difference between ARC in younger age group(ARC-1)and ARC in elder age group(ARC-2)was quite slight.A total of 1305 hypermethylated and 1178 hypomethylated lncRNAs,as well as 182 differential expressed lncRNAs were exhibited in ARC compared with CC.On the other hand,5893 hypermethylated and 5213 hypomethylated lncRNAs,as well as 155 significantly altered lncRNA were identified in ARC-2 compared with ARC-1.Altered lncRNAs in ARC were mainly associated with the organization and biogenesis of intracellular organelles,as well as nucleotide excision repair.CONCLUSION:Our results for the first time present an overview of the m6A methylomes of lncRNA in CC and ARC,providing a solid basis and uncovering a new insight to reveal the potential pathogenic mechanism of CC and ARC.

Long non-coding RNAs with essential roles in neurodegenerative disorders

Recently,with the advent of high-resolution and high-throughput sequencing technologies,an increasing number of long non-coding RNAs(lncRNAs)have been found to be involved in the regulation of neuronal function in the central nervous system with specific spatiotemporal patterns,across different neurodegenerative diseases.However,the underlying mechanisms of lncRNAs during neurodegeneration remain poorly understood.This review provides an overview of the current knowledge of the biology of lncRNAs and focuses on introducing the latest identified roles,regulatory mechanisms,and research status of lncRNAs in Alzheimer's disease,Parkinson's disease,Huntington's disease,and amyotrophic lateral sclerosis.Finally,this review discusses the potential values of lncRNAs as diagnostic biomarkers and therapeutic targets for neurodegenerative diseases,hoping to provide broader implications for developing effective treatments.

Navigating the labyrinth of long non-coding RNAs in colorectal cancer:From chemoresistance to autophagy

Long non-coding RNAs(lncRNAs),with transcript lengths exceeding 200 nucleotides and little or no protein-coding capacity,have been found to impact colorectal cancer(CRC)through various biological processes.LncRNA expression can regulate autophagy,which plays dual roles in the initiation and progression of cancers,including CRC.Abnormal expression of lncRNAs is associated with the emergence of chemoresistance.Moreover,it has been confirmed that targeting autophagy through lncRNA regulation could be a viable approach for combating chemoresistance.Two recent studies titled“Human β-defensin-1 affects the mammalian target of rapamycin pathway and autophagy in colon cancer cells through long non-coding RNA TCONS_00014506”and“Upregulated lncRNA PRNT promotes progression and oxaliplatin resistance of colorectal cancer cells by regulating HIPK2 transcription”revealed novel insights into lncRNAs associated with autophagy and oxaliplatin resistance in CRC,respectively.In this editorial,we particularly focus on the regulatory role of lncRNAs in CRC-related autophagy and chemoresistance since the regulation of chemotherapeutic sensitivity by intervening with the lncRNAs involved in the autophagy process has become a promising new approach for cancer treatment.

Long Non-coding RNA PCED1B Antisense RNA 1 Promotes Cell Proliferation and Invasion in Hepatocellular Carcinoma by Regulating the MicroRNA-34a/CD44 Axis

Objective This study aimed to examine the role of long non-coding RNA PCED1B antisense RNA 1(PCED1B-AS1)in the development of hepatocellular carcinoma(HCC).Methods A total of 62 pairs of HCC tissues and adjacent non-tumor tissues were obtained from 62 HCC patients.The interactions of PCED1B-AS1 and microRNA-34a(miR-34a)were detected by dual luciferase activity assay and RNA pull-down assay.The RNA expression levels of PCED1B-AS1,miR-34a and CD44 were detected by RT-qPCR,and the protein expression level of CD44 was determined by Western blotting.The cell proliferation was detected by cell proliferation assay,and the cell invasion and migration by transwell invasion assay.The HCC tumor growth after PCED1B-AS1 was downregulated was determined by in vivo animal study.Results PCED1B-AS1 was highly expressed in HCC tissues,which was associated with poor survival of HCC patients.Furthermore,PCED1B-AS1 interacted with miR-34a in HCC cells,but they did not regulate the expression of each other.Additionally,PCED1B-AS1 increased the expression level of CD44,which was targeted by miR-34a.The cell proliferation and invasion assay revealed that miR-34a inhibited the proliferation and invasion of HCC in vitro,while CD44 exhibited the opposite effects.Furthermore,PCED1B-AS1 suppressed the role of miR-34a.Moreover,the knockdown of PCED1B-AS1 repressed the HCC tumor growth in nude mice in vivo.Conclusion PCED1B-AS1 may play an oncogenic role by regulating the miR-34a/CD44 axis in HCC.

Expression and significant roles of the long non-coding RNA CASC19/miR-491-5p/HMGA2 axis in the development of gastric cancer

BACKGROUND Gastric cancer(GC)is a common malignant tumor,long non-coding RNA and microRNA(miRNA)are important regulators that affect tumor proliferation,metastasis and chemotherapy resistance,and thus participate in tumor progression.CASC19 is a new bio-marker which can promote tumor invasion and metastasis.However,the mechanism by which CASC19 affects the progression of GC through miRNA is not clear.AIM To explore the role of the CASC19/miR-491-5p/HMGA2 regulatory axis in GC.METHODS To explore the expression and prognosis of CASC19 in GC through clinical samples,and investigate the effects of inhibiting CASC19 on the proliferation,migration,invasion and other functions of GC cells through cell counting Kit-8(CCK-8),ethynyldeoxyuridine,Wound healing assay,Transwell,Western blot and flow cytometry experiments.The effect of miR-491-5p and HMGA2 in GC were also proved.The regulatory relationship between CASC19 and miR-491-5p,miR-491-5p and HMGA2 were validated through Dual-luciferase reporter gene assay and reverse transcription PCR.Then CCK-8,Transwell,Wound healing assay,flow cytometry and animal experiments verify the role of CASC19/miR-491-5p/HMGA2 regulatory axis.RESULTS The expression level of CASC19 is related to the T stage,N stage,and tumor size of patients.Knockdown of the expression of CASC19 can inhibit the ability of proliferation,migration,invasion and EMT conversion of GC cells,and knocking down the expression of CASC19 can promote the apoptosis of GC cells.Increasing the expression of miR-491-5p can inhibit the proliferation of GC cells,miR-491-5p mimics can inhibit EMT conversion,and promote the apoptosis of GC cells,while decreasing the expression of miR-491-5p can promote the proliferation and EMT conversion and inhibit the apoptosis of GC cells.The expression of HMGA2 in GC tissues is higher than that in adjacent tissues.At the same time,the expression level of HMGA2 is related to the N and T stages of the patients.Reducing the level of HMGA2 can promote cell apoptosis and inhibit the proliferation of GC cells.Cell experiments and animal experiments have proved that CASC19 can regulates the expression of HMGA2 through miR-491-5p,thereby affecting the biological functions of GC.CONCLUSION CASC19 regulates the expression of HMGA2 through miR-491-5p to affect the development of GC.This axis may serve as a potential biomarker and therapeutic target of GC.

Construction of prognostic markers for gastric cancer and comprehensive analysis of pyroptosis-related long non-coding RNAs

BACKGROUND China's most frequent malignancy is gastric cancer(GC),which has a very poor survival rate,and the survival rate for patients with advanced GC is dismal.Pyroptosis has been connected to the genesis and development of cancer.The function of pyroptosis-related long non-coding RNAs(PRLs)in GC,on the other hand,remains uncertain.AIM To explore the construction and comprehensive analysis of the prognostic characteristics of long non-coding RNA(lncRNA)related to pyroptosis in GC patients.METHODS The TCGA database provided us with 352 stomach adenocarcinoma samples,and we obtained 28 pyroptotic genes from the Reactome database.We examined the correlation between lncRNAs and pyroptosis using the Pearson correlation coefficient.Prognosis-related PRLs were identified through univariate Cox analysis.A predictive signature was constructed using stepwise Cox regression analysis,and its reliability and independence were assessed.To facilitate clinical application,a nomogram was created based on this signature.we analyzed differences in immune cell infiltration,immune function,and checkpoints between the high-risk group(HRG)and low-risk group(LRG).RESULTS Five hundred and twenty-three PRLs were screened from all lncRNAs(absolute correlation coefficient>0.4,P<0.05).Nine PRLs were included in the risk prediction signature that was created through stepwise Cox regression analysis.We determined the risk score for GC patients and employed the median value as the dividing line between HRG and LRG.The ability of the risk signature to predict the overall survival(OS)of GC is demonstrated by the Kaplan-Meier analysis,risk curve,receiver operating characteristic curve,and decision curve analysis curve.The risk signature was shown to be an independent prognostic factor for OS in both univariate and multivariate Cox regression analyses.HRG showed a more efficient local immune response or modulation compared to LRG,as indicated by the predicted signal pathway analysis and examination of immune cell infiltration,function,and checkpoints(P<0.05).CONCLUSION In general,we have created a brand-new prognostic signature using PRLs,which may provide ideas for immunotherapy in patients with GC.

Long non-coding RNA GATA6-AS1 is mediated by N6-methyladenosine methylation and inhibits the proliferation and metastasis of gastric cancer

BACKGROUND Through experimental research on the biological function of GATA6-AS1,it was confirmed that GATA6-AS1 can inhibit the proliferation,invasion,and migration of gastric cancer cells,suggesting that GATA6-AS1 plays a role as an anti-oncogene in the occurrence and development of gastric cancer.Further experi-ments confirmed that the overexpression of fat mass and obesity-associated protein(FTO)inhibited the expression of GATA6-AS1,thereby promoting the occurrence and development of gastric cancer.AIM To investigate the effects of GATA6-AS1 on the proliferation,invasion and migration of gastric cancer cells and its mechanism of action.METHODS We used bioinformatics methods to analyze the Cancer Genome Atlas(https://portal.gdc.cancer.gov/.The Cancer Genome Atlas)and download expression data for GATA6-AS1 in gastric cancer tissue and normal tissue.We also constructed a GATA6-AS1 lentivirus overexpression vector which was transfected into gastric cancer cells to investigate its effects on proliferation,migration and invasion,and thereby clarify the expression of GATA6-AS1 in gastric cancer and its biological role in the genesis and development of gastric cancer.Next,we used a database(http://starbase.sysu.edu.cn/starbase2/)to analysis GATA6-AS1 whether by m6A methylation modify regulation and predict the methyltransferases that may methylate GATA6-AS1.Furthermore,RNA immunoprecipitation experiments confirmed that GATA6-AS1 was able to bind to the m6A methylation modification enzyme.These data allowed us to clarify the ability of m6A methylase to influence the action of GATA6-AS1 and its role in the occurrence and development of gastric cancer.RESULTS Low expression levels of GATA6-AS1 were detected in gastric cancer.We also determined the effects of GATA6-AS1 overexpression on the biological function of gastric cancer cells.GATA6-AS1 had strong binding ability with the m6A demethylase FTO,which was expressed at high levels in gastric cancer and negatively correlated with the expression of GATA6-AS1.Following transfection with siRNA to knock down the expression of FTO,the expression levels of GATA6-AS1 were up-regulated.Finally,the proliferation,migration and invasion of gastric cancer cells were all inhibited following the knockdown of FTO expression.CONCLUSION During the occurrence and development of gastric cancer,the overexpression of FTO may inhibit the expression of GATA6-AS1,thus promoting the proliferation and metastasis of gastric cancer.

Clinical application value of long non-coding RNAs signatures of genomic instability in predicting prognosis of hepatocellular carcinoma

Hepatocellular carcinoma(HCC)presents challenges due to its high recurrence and metastasis rates and poor prognosis.While current clinical diagnostic and prognostic indicators exist,their accuracy remains imperfect due to their biol-ogical complexity.Therefore,there is a quest to identify improved biomarkers for HCC diagnosis and prognosis.By combining long non-coding RNA(lncRNA)expression and somatic mutations,Duan et al identified five representative lncRNAs from 88 lncRNAs related to genomic instability(GI),forming a GI-derived lncRNA signature(LncSig).This signature outperforms previously re-ported LncSig and TP53 mutations in predicting HCC prognosis.In this editorial,we comprehensively evaluate the clinical application value of such prognostic evaluation model based on sequencing technology in terms of cost,time,and practicability.Additionally,we provide an overview of various prognostic models for HCC,aiding in a comprehensive understanding of research progress in pro-gnostic evaluation methods.

Role of long non-coding RNAs in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease(NAFLD)is emerging as a common cause of chronic liver disease in children and adults.NAFLD can progress to steatohepa-titis and potentially even hepatocellular carcinoma.Early identification of pati-ents at risk for progressive disease is crucial for managing NAFLD.Recent studies have identified long noncoding RNAs(lncRNAs),circular RNAs,and microRNAs as playing important roles in the pathogenesis of NAFLD.These noncoding RNAs are involved in modulating several metabolic pathways such as hepatic glucose and lipid metabolism,oxidative stress,and even carcinogenesis.Elevated levels of lncARSR and lncRNA nuclear-enriched abundant transcript 1 have been found in patients with NAFLD.In addition,lncRNAs such as PRYP4-3 and RP11-128N14.5 can distinguish patients with NAFLD from healthy indi-viduals.Increased MEG3 expression has been observed in both NAFLD and non-alcoholic steatohepatitis,suggesting that it may help predict patients at risk for disease progression.With advances in transcriptomics,we may discover additional targets to help in the identification and prognostication of NAFLD.

Non-coding RNAs in acute ischemic stroke:from brain to periphery

Acute ischemic stroke is a clinical emergency and a condition with high morbidity,mortality,and disability.Accurate predictive,diagnostic,and prognostic biomarkers and effective therapeutic targets for acute ischemic stroke remain undetermined.With innovations in high-throughput gene sequencing analysis,many aberrantly expressed non-coding RNAs(ncRNAs)in the brain and peripheral blood after acute ischemic stroke have been found in clinical samples and experimental models.Differentially expressed ncRNAs in the post-stroke brain were demonstrated to play vital roles in pathological processes,leading to neuroprotection or deterioration,thus ncRNAs can serve as therapeutic targets in acute ischemic stroke.Moreover,distinctly expressed ncRNAs in the peripheral blood can be used as biomarkers for acute ischemic stroke prediction,diagnosis,and prognosis.In particular,ncRNAs in peripheral immune cells were recently shown to be involved in the peripheral and brain immune response after acute ischemic stroke.In this review,we consolidate the latest progress of research into the roles of ncRNAs(microRNAs,long ncRNAs,and circular RNAs)in the pathological processes of acute ischemic stroke–induced brain damage,as well as the potential of these ncRNAs to act as biomarkers for acute ischemic stroke prediction,diagnosis,and prognosis.Findings from this review will provide novel ideas for the clinical application of ncRNAs in acute ischemic stroke.

Urgent need for prognostic markers for hepatocellular carcinoma in the light of genomic instability and non-coding RNA signatures

In this editorial,we comment on an original article by Duan et al.Despite ad-vancements in the diagnosis and treatment of hepatocellular carcinoma(HCC),the identification of suitable prognostic factors remains challenging.In their paper,Duan et al identified long non-coding RNAs(LncRNAs)to quantify ge-nomic instability(GI)by combining LncRNA expression and somatic mutation profiles.They confirmed that the GI-derived LncRNA signature(GI-LncSig)could be an independent prognostic factor with the area under the curve of 0.773.Fur-thermore,the authors stated that GI-LncSig may have a better predictive perfor-mance than TP53 mutation status alone.However,studies exploring genetic markers for predicting the prognosis of HCC are crucial for identifying thera-peutic targets and enhancing diagnostic and treatment strategies to mitigate the global burden of liver cancer.

Involvement of long non-coding RNAs in pear fruit senescence under high-and low-temperature conditions

Pear fruit senescence under high-and low-temperature conditions has been reported to be mediated by microRNAs.Long non-coding RNAs(lncRNAs),which can function as competing endogenous RNAs that interact with microRNAs,may also be involved in temperature-affected fruit senescence.Based on the transcriptome and microRNA sequencings,in this study,3330 lncRNAs were isolated from Pyrus pyrifolia fruit.Of these lncRNAs,2060 and 537 were responsive to high-and low-temperature conditions,respectively.Of these differentially expressed lncRNAs,82 and 24 correlated to the mRNAs involved in fruit senescence under high-and low-temperature conditions,respectively.Moreover,three lncRNAs were predicted to be competing endogenous RNAs(ceRNAs)that interact with the microRNAs involved in fruit senescence,while one and two ceRNAs were involved in fruit senescence under high-and low-temperature conditions,respectively.A dual-luciferase assay showed that the interaction of an lncRNA with a microRNA disrupts the action of the microRNA on the expression of its target mRNA(s).Furthermore,four alternative splicing-derived lncRNAs interacted with miR172i homologies(Novel_88 and Novel_69)to relieve the repressed expression of their target and produce an miR172i precursor.Correlation analysis of microRNA expression suggested that Novel_69 is likely involved in the cleavage of the pre-miR172i hairpin to generate mature miR172i.Taken together,lncRNAs are involved in pear fruit senescence under high-or low-temperature conditions through ceRNAs and the production of microRNA.

Expression profile of long non-coding RNAs in the intestine of black rockfish Sebastes schlegelii in response to Edwardsiella tarda infection

Long non-coding RNAs(lncRNAs)are a class of transcripts longer than 200 bp,which have been emerged as essential regulators in numerous biological processes.Black rockfish(Sebastes schlegelii)is an economic fish that widely cultured in the coastal areas of China,Japan,and South Korea.With the expansion of aquacultural scale,various pathogens have threatened its industry and reduced its economic values.It has been reported that lncRNA were involved in the immune response and metabolic pathway in teleost,while no study is available on identification and functional analysis of lncRNAs in black rockfish so far.Herein,this study was performed to identify lncRNAs in the intestine of black rockfish after Edwardsiella tarda infection.In our results,a total of 9311 lncRNAs were identified through highthroughput sequencing,and 102 lncRNAs were significantly regulated following challenge,which were predicted to target 3348 mRNAs.Results of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses of the se target genes showed they were function in catalytic activity,hydrolase activity,defense response and peptidase activity,which involved in metabolic pathways and immune related pathways.In addition,47 lncRNAs and 8 differentially expressed mRNAs(DEmRNAs)showed co-expression at two or more infection time points with metabolism and immunity functions.Moreover,real-time quantitative PCR(qRT-PCR)was performed to verify the reliability of sequencing gene expression analysis results.This research laid the foundation for further investigation of the regulatory roles of lncRNAs in the intestinal immune response of black rockfish.

Identification and Characterization of Long Non-Coding RNAs Involved in Sex-Related Gene Regulation in Kelp Saccharina japonica

Long non-coding RNAs(lncRNAs)regulate a variety of biological processes,including sexual reproduction and differentiation.Saccharina japonica,a commercially important brown alga in China,shows remarkable sexual dimorphism in haploid gametophytes.The sex of Saccharina japonica gametophytes is determined by UV sexual system.However,no results have been reported on the lncRNAs involved in the sex-related gene regulation of S.japonica.This study identified a number of lncRNAs and assessed their expression levels in male and female gametophytes.Among them,a total of 405 lncRNAs and 211 mRNAs showed differential expressions.Furthermore,the functions of target genes of differentially expressed lncRNAs(DELs)differed from those of differentially expressed genes(DEGs),suggesting that lncRNA may interact with other functional proteins,in addition to DEGs,to involve sex regulation in S.japonica.There were 32 and 90 potential cis-regulatory and trans-regulatory interactions between DELsDEGs,respectively.Five of these lncRNAs(LNC_002974,LNC_021059,LNC_038466,LNC_051584,and LNC_027400)interacted with putative male sex determination region(SDR)genes,suggesting that they act as regulators in gametophytes'sex regulation potentially.Findings from this study contribute to our understanding of the roles of lncRNAs in sex differentiation and lay the foundation for functional studies of candidate lncRNAs in the future.

Bioinformatics Analysis and Experimental Verification of Prognostic and Biological Significance of Autophagy-Related Long Non-Coding RNAs in Gastric Carcinoma

Background:Long non-coding RNAs(lncRNAs)play a vital role in autophagy modulation and tumor progression.However,the key lncRNAs and their functions in gastric cancer(GC)remain largely unknown.Methods:A bioinformatic analysis of GC patients’gene expression profiling data from the Cancer Genome Atlas database was performed to identify autophagy-related lncRNAs that are associated with predictive risk.Through Cox regression and Lasso regression analyses,the autophagy-related lncRNAs that are associated with prognosis were identified,and a novel prognostic model for GC was established.The model was then used to evaluate the clinical features and predictive risk of individuals with GC.By using two datasets,GSE 62254(n=300)and GSE 15459(n=192),from Gene Expression Omnibus,its effectiveness was verified.Gene set enrichment analysis according to hallmark and Kyoto Encyclopedia of Genes and Genomes were used to determine the possible biological roles of these lncRNAs.Furthermore,the HOXD antisense growth-associated long non-coding RNA(HAGLR)mechanism in GC was discovered through in vitro and in vivo experiments.Results:Six lncRNAs associated with autophagy in GC were identified,and a new prognostic risk model based on these lncRNAs was established.The six-lncRNA signature was significantly associated with adverse clinicopathological features and found to be an independent GC prognostic factor.The model was proven to be effective and robust by GSE62254 and GSE15459.According to gene set enrichment analysis,the six lncRNAs appeared to be tightly linked to autophagy-related and cancer-related mechanisms.HAGLR was also found to promote tumor growth by enhancing autophagy signaling in GC.Conclusion:A novel prognostic model integrating HAGLR that can effectively evaluate and predict the prognostic risk of GC patients was established.The results indicated that HAGLR promotes gastric cancer progression by enhancing autophagy and is anticipated to be a potential new target for the treatment of gastric cancer.

Long noncoding RNA steroid receptor RNA activator 1 inhibits proliferation and glycolysis of esophageal squamous cell carcinoma

BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary sites between lncRNA SRA1,miRNA-363-5p,and phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)predicted via bioinformatics analysis stimulated us to hypothesize that miRNA-363-5p/LHPP axis might be required for SRA1-mediated ESCC progression.AIM To investigate the molecular events of SRA1 in the malignant behavior in ESCC.METHODS Thirty-eight ESCC tissues and paired adjacent normal tissues were acquired.SRA1 expression was detected in ESCC tissues and cell lines using quantitative reverse transcription-polymerase chain reaction.Cell counting Kit-8 assay,transwell invasion assay,glycolysis assay,and xenograft tumor model were performed to address the malignant biological behaviors of ESCC cells after the introduction of SRA1.The t-test and theχ2 test were used for comparison between groups.Survival curve analysis was performed using the Kaplan-Meier method.RESULTS SRA1 downregulation was identified in ESCC.ESCC patients exhibiting a low SRA1 expression faced shorter overall survival than those with a high SRA1 expression.The introduction of SRA1 inhibited cell proliferation,glucose uptake,and lactate production in ESCC.In vivo,the growth of ESCC was hindered by SRA1 overexpression.Then,SRA1 overexpresses the LHPP by inhibiting miRNA-363-5p.Lastly,the introduction of small interfering RNA si-LHPP or miRNA-363-5p mimic could abrogate the inhibition roles triggered by SRA1.CONCLUSION SRA1 inhibits the oncogenicity of ESCC via miRNA-363-5p/LHPP axis.The SRA1/miRNA-363-5p/LHPP pathway may be a therapeutic target for ESCC.

The Dual Role of Non-coding RNAs in the Development of Periodontitis

This review aims to sum up how Non-coding RNAs(ncRNAs)regulate the development of periodontitis and provides a new perspective for understanding the pathogenesis of periodontitis.We explored the ncRNA's dual role in the development of periodontitis by summarizing evidence from previous in vivo and in vitro studies as well as clinical samples.In our review,the downregulation of 18 miRNAs,22 lncRNAs and 10 circRNAs demonstrates protective roles in periodontitis.In contrast,the expression of other 11 miRNAs,7 lncRNAs and 6 circRNAs are upregulated in periodontitis,which promote the progression of periodontitis.These dysregulated ncRNAs exert their protective or destructive roles by mainly influencing cell proliferation,differentiation and apoptosis via cross-talking with various molecules or signaling pathways.Our findings suggested which and how ncRNAs promote or delay the progression of periodontitis,which may greatly contribute to diagnose and therapy development of periodontitis based on ncRNAs in the future.

Non-coding RNAs:The potential biomarker or therapeutic target in hepatic ischemia-reperfusion injury

Hepatic ischemia-reperfusion injury(HIRI)is the major complication of liver surgery and liver transplantation,that may increase the postoperative morbidity,mortality,tumor progression,and metastasis.The underlying mechanisms have been extensively investigated in recent years.Among these,oxidative stress,inflammatory responses,immunoreactions,and cell death are the most studied.Non-coding RNAs(ncRNAs)are defined as the RNAs that do not encode proteins,but can regulate gene expressions.In recent years,ncRNAs have emerged as research hotspots for various diseases.During the progression of HIRI,ncRNAs are differentially expressed,while these dysregulations of ncRNAs,in turn,have been verified to be related to the above pathological processes involved in HIRI.ncRNAs mainly contain microRNAs,long ncRNAs,and circular RNAs,some of which have been reported as biomarkers for early diagnosis or assessment of liver damage severity,and as therapeutic targets to attenuate HIRI.Here,we briefly summarize the common pathophysiology of HIRI,describe the current knowledge of ncRNAs involved in HIRI in animal and human studies,and discuss the potential of ncRNA-targeted therapeutic strategies.Given the scarcity of clinical trials,there is still a long way to go from pre-clinical to clinical application,and further studies are needed to uncover their potential as therapeutic targets.

Analysis of long non-coding RNA expression profiles in gastric cancer

AIM: To investigate the expression patterns of long non-coding RNAs (lncRNAs) in gastric cancer. METHODS: Two publicly available human exon arrays for gastric cancer and data for the corresponding normal tissue were downloaded from the Gene Expression Omnibus (GEO). We re-annotated the probes of the human exon arrays and retained the probes uniquely mapping to lncRNAs at the gene level. LncRNA expression profiles were generated by using robust multi-array average method in affymetrix power tools. The normalized data were then analyzed with a Bioconductor package linear models for microarray data and genes with adjusted P -values below 0.01 were considered differentially expressed. An independent data set was used to validate the results. RESULTS: With the computational pipeline established to re-annotate over 6.5 million probes of the Affymetrix Human Exon 1.0 ST array, we identified 136053 probes uniquely mapping to lncRNAs at the gene level. These probes correspond to 9294 lncRNAs, covering nearly 76% of the GENCODE lncRNA data set. By analyzing GSE27342 consisting of 80 paired gastric cancer and normal adjacent tissue samples, we identified 88 lncRNAs that were differentially expressed in gastric cancer, some of which have been reported to play a role in cancer, such as LINC00152, taurine upregulated 1, urothelial cancer associated 1, Pvt1 oncogene, small nucleolar RNA host gene 1 and LINC00261. In the validation data set GSE33335, 59% of these differentially expressed lncRNAs showed significant expression changes (adjusted P -value < 0.01) with the same direction. CONCLUSION: We identified a set of lncRNAs differentially expressed in gastric cancer, providing useful information for discovery of new biomarkers and therapeutic targets in gastric cancer.

Diagnostic and prognostic potential of tissue and circulating long non-coding RNAs in colorectal tumors

Long non-coding RNAs(lncRNAs)are members of the non-protein coding RNA family longer than 200 nucleotides.They participate in the regulation of gene and protein expression influencing apoptosis,cell proliferation and immune responses,thereby playing a critical role in the development and progression of various cancers,including colorectal cancer(CRC).As CRC is one of the most frequently diagnosed malignancies worldwide with high mortality,its screening and early detection are crucial,so the identification of disease-specific biomarkers is necessary.LncRNAs are promising candidates as they are involved in carcinogenesis,and certain lncRNAs(e.g.,CCAT1,CRNDE,CRCAL1-4)show altered expression in adenomas,making them potential early diagnostic markers.In addition to being useful as tissue-specific markers,analysis of circulating lncRNAs(e.g.,CCAT1,CCAT2,BLACAT1,CRNDE,NEAT1,UCA1)in peripheral blood offers the possibility to establish minimally invasive,liquid biopsy-based diagnostic tests.This review article aims to describe the origin,structure,and functions of lncRNAs and to discuss their contribution to CRC development.Moreover,our purpose is to summarise lncRNAs showing altered expression levels during tumor formation in both colon tissue and plasma/serum samples and to demonstrate their clinical implications as diagnostic or prognostic biomarkers for CRC.