Construction and validation of somatic mutation-derived long noncoding RNAs signatures of genomic instability to predict prognosis of hepatocellular carcinoma

BACKGROUND Long non-coding RNAs(LncRNAs)have been found to be a potential prognostic factor for cancers,including hepatocellular carcinoma(HCC).Some LncRNAs have been confirmed as potential indicators to quantify genomic instability(GI).Nevertheless,GI-LncRNAs remain largely unexplored.This study established a GI-derived LncRNA signature(GILncSig)that can predict the prognosis of HCC patients.AIM To establish a GILncSig that can predict the prognosis of HCC patients.METHODS Identification of GI-LncRNAs was conducted by combining LncRNA expression and somatic mutation profiles.The GI-LncRNAs were then analyzed for functional enrichment.The GILncSig was established in the training set by Cox regression analysis,and its predictive ability was verified in the testing set and TCGA set.In addition,we explored the effects of the GILncSig and TP53 on prognosis.RESULTS A total of 88 GI-LncRNAs were found,and functional enrichment analysis showed that their functions were mainly involved in small molecule metabolism and GI.The GILncSig was constructed by 5 LncRNAs(miR210HG,AC016735.1,AC116351.1,AC010643.1,LUCAT1).In the training set,the prognosis of high-risk patients was significantly worse than that of low-risk patients,and similar results were verified in the testing set and TCGA set.Multivariate Cox regression analysis and stratified analysis confirmed that the GILncSig could be used as an independent prognostic factor.Receiver operating characteristic curve analysis of the GILncSig showed that the area under the curve(0.773)was higher than the two LncRNA signatures published recently.Furthermore,the GILncSig may have a better predictive performance than TP53 mutation status alone.CONCLUSION We established a GILncSig that can predict the prognosis of HCC patients,which will help to guide prognostic evaluation and treatment decisions.

Lipid metabolism-related long noncoding RNAs:A potential prognostic biomarker for hepatocellular carcinoma

The incidence rates of hepatocellular carcinoma(HCC)have increased in recent decades.Despite advancements in therapy and early diagnosis improving shortterm prognosis,long-term outcomes remain poor.Long noncoding RNAs(lncRNAs)and lipid metabolism play crucial roles in the development and progression of HCC.Enhanced lipid synthesis promotes HCC progression,and lncRNAs can reprogram the expression of lipogenic enzymes.Consequently,lipid metabolism-related(LMR)-lncRNAs regulate lipid anabolism,accelerating the onset and progression of HCC.This suggests that LMR-lncRNAs could serve as novel prognostic biomarkers and therapeutic targets.

Curcumin inhibits the growth and invasion of gastric cancer by regulating long noncoding RNA AC022424.2

BACKGROUND Gastric cancer,characterized by a multifactorial etiology and high heterogeneity,continues to confound researchers in terms of its pathogenesis.Curcumin,a natural anticancer agent,exhibits therapeutic promise in gastric cancer.Its effects include promoting cell apoptosis,curtailing tumor angiogenesis,and enhancing sensitivity to radiation and chemotherapy.Long noncoding RNAs(lncRNAs)have garnered significant attention as biomarkers for early screening,diagnosis,treatment,and drug response because of their remarkable specificity and sensitivity.Recent investigations have revealed an association between aberrant lncRNA expression and early diagnosis,clinical staging,metastasis,drug sensitivity,and prognosis in gastric cancer.A profound understanding of the intricate mechanisms through which lncRNAs influence gastric cancer develop-ment can provide novel insights for precision treatment and tailored management of patients with gastric cancer.This study aimed to unravel the potential of curcumin in suppressing the malignant behavior of gastric cancer cells by upregu-lating specific lncRNAs and modulating gastric cancer onset and progression.AIM To identify lncRNAs associated with curcumin treatment and investigate the role of lncRNA AC022424.2 in the effects of curcumin on gastric cancer cell apoptosis,proliferation,and invasion.Furthermore,these findings were validated in clinical samples.METHODS The study employed CCK-8 assays to assess the impact of curcumin on gastric cancer cell proliferation,flow cytometry to investigate its effects on apoptosis,and scratch and Transwell assays to evaluate its influence on the migration and invasion of BGC-823 and MGC-803 cells.Western blotting was used to gauge changes in the protein expression levels of CDK6,CDK4,Bax,Bcl-2,caspase-3,P65,and the PI3K/Akt/mTOR pathway in gastric cancer cell lines after curcumin treatment.Differential expression of lncRNAs before and after curcumin treatment was assessed using lncRNA sequencing and validated using quantitative reverse transcription polymerase chain reaction(qRT-PCR)in BGC-823 and MGC-803 cells.AC022424.2-1 knockdown BGC-823 and MGC-803 cells were generated to scrutinize the impact of lncRNA AC022424.2 on apoptosis,proliferation,migration,and invasion of gastric cancer cells.Western blotting was performed to ascertain changes in the expression of proteins implicated in the PI3K/Akt/mTOR and NF-κB signaling pathways.RT-PCR was employed to measure lncRNA AC022424.2 expression in clinical gastric cancer tissues and to correlate its expression with clinical pathological characteristics.RESULTS Curcumin induced apoptosis and hindered proliferation,migration,and invasion of gastric cancer cells in a dose-and time-dependent manner.LncRNA AC022424.2 was upregulated after curcumin treatment,and its knockdown enhanced cancer cell aggressiveness.LncRNA AC022424.2 may have affected cancer cells via the PI3K/Akt/mTOR and NF-κB signaling pathways.LncRNA AC022424.2 downregulation was correlated with lymph node metastasis,making it a potential diagnostic and prognostic marker.CONCLUSION Curcumin has potential anticancer effects on gastric cancer cells by regulating lncRNA AC022424.2.This lncRNA plays a significant role in cancer cell behavior and may have clinical implications in diagnosis and prognosis evaluation.The results of this study enhance our understanding of gastric cancer development and precision treatment.

Long noncoding RNAs HAND2-AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2 axis

BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2-AS1 was downregulated in HCC tissues,but its role in HCC progression is unclear.Ultrasound targeted microbubble destruction mediated gene transfection is a new method to overexpress genes.AIM To study the role of ultrasound microbubbles(UTMBs)mediated HAND2-AS1 in the progression of HCC,in order to provide a new reference for the treatment of HCC.METHODS In vitro,we transfected HAND2-AS1 siRNA into HepG2 cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,respectively.In addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell behavior.Next,the UTMBs treated HepG2 cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2(TIMP2)overexpression vector,and we detected cell proliferation,apoptosis,invasion and EMT.In vivo,we established a mouse model of subcutaneous transplantation of HepG2 cells and observed the effect of HAND2-AS1 silencing on tumor formation ability.RESULTS We found that UTMBs carrying HAND2-AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2-AS1 silencing eliminated the effect of UTMBs.Additionally,miR-873-5p targets the gene HAND2-AS1,which also targets the 3’UTR of TIMP2.And miR-873-5p mimic counteracted the impact of HAND2-AS1.Further,miR-873-5p mimic solely or in combination with pcDNA-TIMP2 had been transformed into HepG2 cells exposed to UTMBs.We discovered that TIMP2 reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2/MMP9.In vivo results showed that HAND2-AS1 silencing significantly inhibited tumor formation in mice.CONCLUSION LncRNA HAND2-AS1 promotes TIMP2 expression by targeting miR-873-5p to inhibit HepG2 cell growth and delay HCC progression.

Long noncoding RNA protein-disulfide isomerase-associated 3 regulated high glucose-induced podocyte apoptosis in diabetic nephropathy through targeting miR-139-3p

BACKGROUND Podocyte apoptosis plays a vital role in proteinuria pathogenesis in diabetic nephropathy(DN).The regulatory relationship between long noncoding RNAs(lncRNAs)and podocyte apoptosis has recently become another research hot spot in the DN field.AIM To investigate whether lncRNA protein-disulfide isomerase-associated 3(Pdia3)could regulate podocyte apoptosis through miR-139-3p and revealed the underlying mechanism.METHODS Using normal glucose or high glucose(HG)-cultured podocytes,the cellular functions and exact mechanisms underlying the regulatory effects of lncRNA Pdia3 on podocyte apoptosis and endoplasmic reticulum stress(ERS)were explored.LncRNA Pdia3 and miR-139-3p expression were measured through quantitative real-time polymerase chain reaction.Relative cell viability was detected through the cell counting kit-8 colorimetric assay.The podocyte apoptosis rate in each group was measured through flow cytometry.The interaction between lncRNA Pdia3 and miR-139-3p was examined through the dual luciferase reporter assay.Finally,western blotting was performed to detect the effect of lncRNA Pdia3 on podocyte apoptosis and ERS via miR-139-3p.RESULTS The expression of lncRNA Pdia3 was significantly downregulated in HG-cultured podocytes.Next,lncRNA Pdia3 was involved in HG-induced podocyte apoptosis.Furthermore,the dual luciferase reporter assay confirmed the direct interaction between lncRNA Pdia3 and miR-139-3p.LncRNA Pdia3 overexpression attenuated podocyte apoptosis and ERS through miR-139-3p in HG-cultured podocytes.CONCLUSION Taken together,this study demonstrated that lncRNA Pdia3 overexpression could attenuate HG-induced podocyte apoptosis and ERS by acting as a competing endogenous RNA of miR-139-3p,which might provide a potential therapeutic target for DN.

Integrating disulfidptosis-related long noncoding RNAs in colorectal cancer prognosis:A path to precision medicine

This commentary explores the burgeoning field of disulfidptosis-related long noncoding RNAs(lncRNAs)in the prognosis and therapeutic targeting of colorectal cancer(CRC).By evaluating recent research,including the pivotal study"Predicting colorectal cancer prognosis based on long noncoding RNAs of disulfidptosis genes"by Wang et al,this analysis underscores the critical role of lncRNAs in deciphering the molecular complexities of CRC.Highlighting the innovative methodologies and significant findings,I discuss the implications for patient survival,therapeutic response,and the potential of lncRNAs as biomarkers for precision medicine.The integration of bioinformatics,clinical databases,and molecular biology in these studies offers a promising avenue for advancing CRC treatment strategies and improving patient outcomes.

Prognostic value of the long noncoding RNA AFAP1-AS1 in cancers

Objective This meta-analysis explored whether the expression of actin filament-associated protein 1 antisense RNA 1(AFAP1-AS1)is related to the prognosis and clinicopathological features of patients with cancer.Methods PubMed,EMBASE,and Cochrane Library were systematically searched.Hazard ratios(HRs)with 95%confidence intervals(CIs)were used to assess the prognostic value based on overall survival(OS),disease-free survival(DFS),and progression-free survival(PFS).Odds ratios(ORs)with 95%CIs were used to determine the relationships between AFAP1-AS1 and clinicopathological features,such as large tumor size(LTS),high tumor stage(HTS),poor histological grade(PHG),lymph node metastasis(LNM),and distant metastasis(DM).Results Thirty-five eligible articles and 3433 cases were analyzed.High AFAP1-AS1 expression,compared to low AFAP1-AS1 expression,correlated with significantly shorter OS(HR=2.15,95%CI=1.97-2.34,P<0.001),DFS(HR=1.37,95%CI=1.19-1.57,P<0.001),and PFS(HR=1.97,95%CI=1.56-2.50,P<0.001)in patients with cancer.In various cancers,elevated AFAP1-AS1 expression was significantly associated with LTS(OR=2.76,95%CI=2.16-3.53,P<0.001),HTS(OR=2.23,95%CI=1.83-2.71,P<0.001),and PHG(OR=1.39,95%CI=1.08-1.79,P=0.01)but not LNM(OR=1.59,95%CI=0.88-2.85,P=0.12)or DM(OR=1.81,95%CI=0.90-3.66,P=0.10).Conclusion High AFAP1-AS1 expression was associated with prognostic and clinicopathological features,suggesting that AFAP1-AS1 is a prognostic biomarker for human cancers.

Upregulation of long noncoding RNA W42 promotes tumor development by binding with DBN1 in hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC)is a malignancy found globally.Accumulating studies have shown that long noncoding RNAs(lncRNAs)play critical roles in HCC.However,the function of lncRNA in HCC remains poorly understood.AIM To understand the effect of lncRNA W42 on HCC and dissect the underlying molecular mechanisms.METHODS We measured the expression of lncRNA W42 in HCC tissues and cells(Huh7 and SMMC-7721)by quantitative reverse transcriptase polymerase chain reaction.Receiver operating characteristic curves were used to assess the sensitivity and specificity of lncRNA W42 expression.HCC cells were transfected with pcDNA3.1-lncRNA W42 or shRNA-lncRNA W42.Cell functions were detected by cell counting Kit-8(CCK-8),colony formation,flow cytometry and Transwell assays.The interaction of lncRNA W42 and DBN1 was confirmed by RNA immunoprecipitation and RNA pull down assays.An HCC xenograft model was used to assess the role of lncRNA W42 on tumor growth in vivo.The Kaplan-Meier curve was used to evaluate the overall survival and recurrence-free survival after surgery in patients with HCC.RESULTS In this study,we identified a novel lncRNA(lncRNA W42),and investigated its biological functions and clinical significance in HCC.LncRNA W42 expression was upregulated in HCC tissues and cells.Overexpression of lncRNA W42 notably promoted the proliferative and invasion of HCC,and inhibited cell apoptosis.LncRNA W42 directly bound to DBN1 and activated the downstream pathway.LncRNA W42 knockdown suppressed HCC xenograft tumor growth in vivo.The clinical investigation revealed that HCC patients with high lncRNA W42 expression exhibited shorter survival times.CONCLUSION In vitro and in vivo results suggested that the novel lncRNA W42,which is upregulated in HCC,may serve as a potential candidate prognostic biomarker and therapeutic target in HCC patients.

Plasma long noncoding RNA expression profile identified by microarray in patients with Crohn's disease

AIM: To investigate the expression pattern of plasma long noncoding RNAs (lncRNAs) in Chrohn&#x02019;s disease (CD) patients.METHODS: Microarray screening and qRT-PCR verification of lncRNAs and mRNAs were performed in CD and control subjects, followed by hierarchy clustering, GO and KEGG pathway analyses. Significantly dysregulated lncRNAs were categorized into subgroups of antisense lncRNAs, enhancer lncRNAs and lincRNAs. To predict the regulatory effect of lncRNAs on mRNAs, a CNC network analysis was performed and cross linked with significantly changed lncRNAs. The overlapping lncRNAs were randomly selected and verified by qRT-PCR in a larger cohort.RESULTS: Initially, there were 1211 up-regulated and 777 down-regulated lncRNAs as well as 1020 up-regulated and 953 down-regulated mRNAs after microarray analysis; a heat map based on these results showed good categorization into the CD and control groups. GUSBP2 and {'type':'entrez-nucleotide','attrs':{'text':'AF113016','term_id':'6642755','term_text':'AF113016'}}AF113016 had the highest fold change of the up- and down-regulated lncRNAs, whereas TBC1D17 and CCL3L3 had the highest fold change of the up- and down-regulated mRNAs. Six (SNX1, CYFIP2, CD6, CMTM8, STAT4 and IGFBP7) of 10 mRNAs and 8 ({'type':'entrez-nucleotide','attrs':{'text':'NR_033913','term_id':'299890801','term_text':'NR_033913'}}NR_033913, {'type':'entrez-nucleotide','attrs':{'text':'NR_038218','term_id':'333360887','term_text':'NR_038218'}}NR_038218, {'type':'entrez-nucleotide','attrs':{'text':'NR_036512','term_id':'302393555','term_text':'NR_036512'}}NR_036512, {'type':'entrez-nucleotide','attrs':{'text':'NR_049759','term_id':'388240827','term_text':'NR_049759'}}NR_049759, {'type':'entrez-nucleotide','attrs':{'text':'NR_033951','term_id':'300068996','term_text':'NR_033951'}}NR_033951, {'type':'entrez-nucleotide','attrs':{'text':'NR_045408','term_id':'354548835','term_text':'NR_045408'}}NR_045408, {'type':'entrez-nucleotide','attrs':{'text':'NR_038377','term_id':'335334999','term_text':'NR_038377'}}NR_038377 and {'type':'entrez-nucleotide','attrs':{'text':'NR_039976','term_id':'337756399','term_text':'NR_039976'}}NR_039976) of 14 lncRNAs showed the same change trends on the microarray and qRT-PCR results with statistical significance. Based on the qRT-PCR verified mRNAs, 1358 potential lncRNAs with 2697 positive correlations and 2287 negative correlations were predicted by the CNC network.CONCLUSION: The plasma lncRNAs profiles provide preliminary data for the non-invasive diagnosis of CD and a resource for further specific lncRNA-mRNA pathway exploration.

Long noncoding RNA X-inactive specific transcript regulates NLR family pyrin domain containing 3/caspase-1-mediated pyroptosis in diabetic nephropathy

BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.

Epigenetic regulation by long noncoding RNAs in osteo-/adipogenic differentiation of mesenchymal stromal cells and degenerative bone diseases

Bone is a complex tissue that undergoes constant remodeling to maintain homeostasis,which requires coordinated multilineage differentiation and proper proliferation of mesenchymal stromal cells(MSCs).Mounting evidence indicates that a disturbance of bone homeostasis can trigger degenerative bone diseases,including osteoporosis and osteoarthritis.In addition to conventional genetic modifications,epigenetic modifications(i.e.,DNA methylation,histone modifications,and the expression of noncoding RNAs)are considered to be contributing factors that affect bone homeostasis.Long noncoding RNAs(lncRNAs)were previously regarded as‘transcriptional noise’with no biological functions.However,substantial evidence suggests that lncRNAs have roles in the epigenetic regulation of biological processes in MSCs and related diseases.In this review,we summarized the interactions between lncRNAs and epigenetic modifiers associated with osteo-/adipogenic differentiation of MSCs and the pathogenesis of degenerative bone diseases and highlighted promising lncRNA-based diagnostic and therapeutic targets for bone diseases.

Long noncoding RNAs in neurodevelopment and Parkinson’s disease

Long noncoding RNAs(lnc RNAs) are RNA molecules comprising more than 200 nucleotides, which are not translated into proteins. Many studies have shown that lnc RNAs are involved in regulating a variety of biological processes, including immune, cancer, stress, development and differentiation at the transcriptional, epigenetic or post-transcriptional levels. Here, we review the role of lnc RNAs in the process of neurodevelopment, neural differentiation, synaptic function, and pathogenesis of Parkinson’s disease(PD). These pathomechanisms include protein misfolding and aggregation, disordered protein degradation, mitochondrial dysfunction, oxidative stress, autophagy, apoptosis, and neuroinflammation. This information will provide the basis of lnc RNA-based disease diagnosis and drug treatment for PD.

Role of long noncoding RNA-mediated competing endogenous RNA regulatory network in hepatocellular carcinoma

Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are noncodingRNAs (ncRNAs) that occupy over 90% of the human genome, and their mainfunction is to directly or indirectly regulate messenger RNA (mRNA) expressionand participate in the tumorigenesis and progression of malignances. Inparticular, some lncRNAs can interact with miRNAs as competing endogenousRNAs (ceRNAs) to modulate mRNA expression. Accordingly, these RNAmolecules are interrelated and coordinate to form a dynamic lncRNA-mediatedceRNA regulatory network. Mounting evidence has revealed that lncRNAs thatact as ceRNAs are closely related to tumorigenesis. To date, numerous studieshave established many different regulatory networks in hepatocellular carcinoma(HCC), and perturbations in these ceRNA interactions may result in the initiationand progression of HCC. Herein, we emphasize recent advances concerning thebiological function of lncRNAs as ceRNAs in HCC, with the aim of elucidating themolecular mechanism underlying these HCC-related RNA molecules andproviding novel insights into the diagnosis and treatment of HCC.

Long noncoding RNA ZNFX1-AS1 promotes the invasion and proliferation of gastric cancer cells by regulating LIN28 and CAPR1N1

BACKGROUND Long noncoding RNA(lncRNA)ZNFX1-AS1(ZFAS1)is a newly discovered lncRNA,but its diagnostic value in gastric cancer is unclear.AIM To investigate the potential role of ZFAS1 in gastric cancer and to evaluate the clinical significance of ZFAS1 as a biomarker for gastric cancer screening.METHODS Quantitative real-time polymerase chain reaction(qRT-PCR)was used to screen for gastric cancer-associated lncRNAs in gastric cancer patients,gastric stromal tumor patients,gastritis or gastric ulcer patients,and healthy controls.Correlations between ZFAS1 expression and clinicopathological features were analyzed.The biological effects of ZFAS1 on the proliferation,migration,and invasion of gastric cancer cells were studied by MTT,colony formation,and transwell migration assays.The potential mechanism of ZFAS1 was demonstrated using enzyme-linked immunosorbent assay and qRT-PCR.The relationship between ZFAS1 and tumorigenesis was demonstrated using in vivo tumor formation assays.RESULTS The plasma level of lncRNA ZFAS1 was significantly higher in preoperative patients with gastric cancer than in individuals in the other 4 groups.Increased expression of ZFAS1 was significantly associated with lymph node metastasis,advanced TNM stage,and poor prognosis.ZFAS1 regulated the proliferation,migration,and invasion of gastric cancer cells and regulated the growth of gastric cancer cells in vivo.LIN28 and CAPRIN1 were identified as key downstream mediators of ZFAS1 in gastric cancer cells.CONCLUSION LncRNA ZFAS1 promoted the invasion and proliferation of gastric cancer cells by modulating LIN28 and CAPRIN1 expression,suggesting that ZFAS1 can be used as a potential diagnostic and prognostic biomarker in gastric cancer.

Long noncoding RNAs in gastric cancer: From molecular dissection to clinical application

Long noncoding RNAs(lncRNAs)are important regulators of cell processes that are usually dysregulated in gastric cancer(GC).Based on their high specificity and ease of detection in tissues and body fluids,increasing attention has spurred the study of the roles of lncRNAs in GC patients.Thus,it is necessary to elucidate the molecular mechanisms and further explore the clinical applications of lncRNAs in GC.In this review,we summarize current knowledge to examine dysregulated lncRNAs in GC and their underlying molecular mechanisms and activities in GC,which involve microRNA sponging,mRNA stability,genetic variants,alternative splicing,transcription factor binding,and epigenetic modification.More significantly,the potential of lncRNAs as prognostic,circulating,and drug-resistant biomarkers for GC is also described.This review highlights the method of dissecting molecular mechanisms to explore the clinical application of lncRNAs in GC.Overall,this review offers assistance in using lncRNAs as novel candidates for molecular mechanisms and for the identification of revolutionary biomarkers for GC.

Long noncoding RNA negative regulator of antiviral response contributes to pancreatic ductal adenocarcinoma progression via targeting miR-299-3p

BACKGROUND Pancreatic ductal cancer(PDAC)has high malignancy and poor prognosis.Long noncoding RNAs(lncRNAs)are associated with high levels of malignancy,including PDAC.However,the biological and clinical significance of negative regulator of antiviral response(NRAV)in PDAC is unclear.AIM To study the regulatory role of lncRNA NRAV in PDAC.METHODS GEPIA analyzed lncRNA NRAV and miRNA(miR-299-3p)expression levels in PDAC tissues and measured them in PDAC cells by quantitative measurements in real time.The specific role of NRAV and miR-299-3p in cell proliferation and transfer potential was evaluated by cell formation analysis,Cell Counting Kit-8 and Transwell analysis.The relationship between NRAV and miR-299-3p was studied by predictive bioinformatics,RNA immunoassay,and fluorescence enzyme analysis.In vivo experiments included transplantation of simulated tumor cells under naked mice.RESULTS The expression level of lncRNA NRAV was higher in both tumor tissues and cell lines of PDAC and was negatively associated with the clinical survival of PDAC patients.Functionally,overexpression of NRAV promoted cell proliferation and metastasis of PDAC cells,while knockdown of NRAV reversed these effects.Finally,NRAV was performed as a molecular sponge of miR-299-3p.Moreover,overexpression of miR-299-3p could reverse the promoting effects of NRAV on cell proliferation and metastasis of PDAC cells.CONCLUSION NRAV facilitates progression of PDAC as a molecular sponge of miR-299-3p and may be a potential molecular marker for diagnosis and treatment of PDAC.

Expression profiles of long noncoding RNAs in retinopathy of prematurity

Long noncoding RNA(lncRNA)regulates the proliferation and migration of human retinal endothelial cells,as well as retinal neovascularization in diabetic retinopathy.Based on similarities between the pathogenesis of retinopathy of prematurity(ROP)and diabetic retinopathy,lncRNA may also play a role in ROP.Seven-day-old mice were administered 75±2% oxygen for 5 days and normoxic air for another 5 days to establish a ROP model.Expression of lncRNA and mRNA in the retinal tissue of mice was detected by high-throughput sequencing technology,and biological functions of the resulted differentially expressed RNAs were evaluated by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses.The results showed that compared with the control group,57 lncRNAs were differentially expressed,including 43 upregulated and 14 downregulated,in the retinal tissue of ROP mice.Compared with control mice,42 mRNAs were differentially expressed in the retinal tissue of ROP mice,including 24 upregulated and 18 downregulated mRNAs.Differentially expressed genes were involved in ocular development and related metabolic pathways.The differentially expressed lncRNAs may regulate ROP in mice via microRNAs and multiple signaling pathways.Our results revealed that these differentially expressed lncRNAs may be therapeutic targets for ROP treatment.This study was approved by the Medical Ethics Committee of Shengjing Hospital of China Medical University on February 25,2016(approval No.2016PS074K).

Expression and regulatory network of long noncoding RNA in rats after spinal cord hemisection injury

Long noncoding RNAs(lncRNAs)participate in a variety of biological processes and diseases.However,the expression and function of lncRNAs after spinal cord injury has not been extensively analyzed.In this study of right side hemisection of the spinal cord at T10,we detected the expression of lncRNAs in the proximal tissue of T10 lamina at different time points and found 445 lncRNAs and 6522 mRNA were differentially expressed.We divided the differentially expressed lncRNAs into 26 expression trends and analyzed Profile 25 and Profile 2,the two expression trends with the most significant difference.Our results showed that the expression of 68 lncRNAs in Profile 25 rose first and remained high 3 days post-injury.There were 387 mRNAs co-expressed with the 68 lncRNAs in Profile 25.The co-expression network showed that the co-expressed genes were mainly enriched in cell division,inflammatory response,FcγR-mediated cell phagocytosis signaling pathway,cell cycle and apoptosis.The expression of 56 lncRNAs in Profile2 first declined and remained low after 3 days post-injury.There were 387 mRNAs co-expressed with the 56 lncRNAs in Profile 2.The co-expression network showed that the co-expressed genes were mainly enriched in the chemical synaptic transmission process and in the signaling pathway of neuroactive ligand-receptor interaction.The results provided the expression and regulatory network of the main lncRNAs after spinal cord injury and clarified their co-expressed gene enriched biological processes and signaling pathways.These findings provide a new direction for the clinical treatment of spinal cord injury.

Long noncoding RNAs:new insights in modulating mammalian spermatogenesis

Spermatogenesis is a complex differentiating developmental process in which undifferentiated spermatogonial germ cells differentiate into spermatocytes,spermatids,and finally,to mature spermatozoa.This multistage developmental process of spermatogenesis involves the expression of many male germ cell-specific long noncoding RNAs(lncRNAs)and highly regulated and specific gene expression.LncRNAs are a recently discovered large class of noncoding cellular transcripts that are still relatively unexplored.Only a few of them have postmeiotic;however,lncRNAs are involved in many cellular biological processes.The expression of lncRNAs is biologically relevant in the highly dynamic and complex program of spermatogenesis and has become a research focus in recent genome studies.This review considers the important roles and novel regulatory functions whereby lncRNAs modulate mammalian spermatogenesis.

S100 calcium binding protein A6 and associated long noncoding ribonucleic acids as biomarkers in the diagnosis and staging of primary biliary cholangitis

BACKGROUND Primary biliary cholangitis(PBC)is a chronic and slowly progressing cholestatic disease,which causes damage to the small intrahepatic bile duct by immunoregulation,and may lead to cholestasis,liver fibrosis,cirrhosis and,eventually,liver failure.AIM To explore the potential diagnosis and staging value of plasma S100 calcium binding protein A6(S100A6)messenger ribonucleic acid(mRNA),LINC00312,LINC00472,and LINC01257 in primary biliary cholangitis.METHODS A total of 145 PBC patients and 110 healthy controls(HCs)were enrolled.Among them,80 PBC patients and 60 HCs were used as the training set,and 65 PBC patients and 50 HCs were used as the validation set.The relative expression levels of plasma S100A6 mRNA,long noncoding ribonucleic acids LINC00312,LINC00472 and LINC01257 were analyzed using quantitative reverse transcription-polymerase chain reaction.The bile duct ligation(BDL)mouse model was used to simulate PBC.Then double immunofluorescence was conducted to verify the overexpression of S100A6 protein in intrahepatic bile duct cells of BDL mice.Human intrahepatic biliary epithelial cells were treated with glycochenodeoxycholate to simulate the cholestatic environment of intrahepatic biliary epithelial cells in PBC.RESULTS The expression of S100A6 protein in intrahepatic bile duct cells was up-regulated in the BDL mouse model compared with sham mice.The relative expression levels of plasma S100A6 mRNA,log10 LINC00472 and LINC01257 were upregulated while LINC00312 was down-regulated in plasma of PBC patients compared with HCs(3.01±1.04 vs 2.09±0.87,P<0.0001;2.46±1.03 vs 1.77±0.84,P<0.0001;3.49±1.64 vs 2.37±0.96,P<0.0001;1.70±0.33 vs 2.07±0.53,P<0.0001,respectively).The relative expression levels of S100A6 mRNA,LINC00472 and LINC01257 were up-regulated and LINC00312 was down-regulated in human intrahepatic biliary epithelial cells treated with glycochenodeoxycholate compared with control(2.97±0.43 vs 1.09±0.08,P=0.0018;2.70±0.26 vs 1.10±0.10,P=0.0006;2.23±0.21 vs 1.10±0.10,P=0.0011;1.20±0.04 vs 3.03±0.15,P<0.0001,respectively).The mean expression of S100A6 in the advanced stage(III and IV)of PBC was up-regulated compared to that in HCs and the early stage(II)(3.38±0.71 vs 2.09±0.87,P<0.0001;3.38±0.71 vs 2.57±1.21,P=0.0003,respectively);and in the early stage(II),it was higher than that in HCs(2.57±1.21 vs 2.09±0.87,P=0.03).The mean expression of LINC00312 in the advanced stage was lower than that in the early stage and HCs(1.39±0.29 vs 1.56±0.33,P=0.01;1.39±0.29 vs 2.07±0.53,P<0.0001,respectively);in addition,the mean expression of LINC00312 in the early stage was lower than that in HCs(1.56±0.33 vs 2.07±0.53,P<0.0001).The mean expression of log10 LINC00472 in the advanced stage was higher than those in the early stage and HCs(2.99±0.87 vs 1.81±0.83,P<0.0001;2.99±0.87 vs 1.77±0.84,P<0.0001,respectively).The mean expression of LINC01257 in both the early stage and advanced stage were up-regulated compared with HCs(3.88±1.55 vs 2.37±0.96,P<0.0001;3.57±1.79 vs 2.37±0.96,P<0.0001,respectively).The areas under the curves(AUC)for S100A6,LINC00312,log10 LINC00472 and LINC01257 in PBC diagnosis were 0.759,0.7292,0.6942 and 0.7158,respectively.Furthermore,the AUC for these four genes in PBC staging were 0.666,0.661,0.839 and 0.5549,respectively.The expression levels of S100A6 mRNA,log10 LINC00472,and LINC01257 in plasma of PBC patients were decreased(2.35±1.02 vs 3.06±1.04,P=0.0018;1.99±0.83 vs 2.33±0.96,P=0.036;2.84±0.92 vs 3.69±1.54,P=0.0006),and the expression level of LINC00312 was increased(1.95±0.35 vs 1.73±0.32,P=0.0007)after treatment compared with before treatment using the paired t-test.Relative expression of S100A6 mRNA was positively correlated with log10 LINC00472(r=0.683,P<0.0001);serum level of collagen type IV was positively correlated with the relative expression of log10 LINC00472(r=0.482,P<0.0001);relative expression of S100A6 mRNA was positively correlated with the serum level of collagen type IV(r=0.732,P<0.0001).The AUC for the four biomarkers obtained in the validation set were close to the training set.CONCLUSION These four genes may potentially act as novel biomarkers for the diagnosis of PBC.Moreover,LINC00472 acts as a potential biomarker for staging in PBC.