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.

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.

Novel insights on oral squamous cell carcinoma management using long non-coding RNAs

Oral squamous cell carcinoma(OSCC)is one of the most prevalent forms of head and neck squamous cell carcinomas(HNSCC)with a poor overall survival rate(about 50%),particularly in cases of metastasis.RNA-based cancer biomarkers are a relatively advanced concept,and non-coding RNAs currently have shown promising roles in the detection and treatment of various malignancies.This review underlines the function of long non-coding RNAs(lncRNAs)in the OSCC and its subsequent clinical implications.LncRNAs,a class of non-coding RNAs,are larger than 200 nucleotides and resemble mRNA in numerous ways.However,unlike mRNA,lncRNA regulates multiple druggable and non-druggable signaling molecules through simultaneous interaction with DNA,RNA,proteins,or microRNAs depending on concentration and localization in cells.Upregulation of oncogenic lncRNAs and downregulation of tumor suppressor lncRNAs are evident in OSCC tissues and body fluids such as blood and saliva indicating their potential as valuable biomarkers.Targeted inhibition of candidate oncogenic lncRNAs or overexpression of tumor suppressor lncRNAs showed potential therapeutic roles in in-vivo animal models.The types of lncRNAs that are expressed differentially in OSCC tissue and bodily fluids have been systematically documented with specificity and sensitivity.This review thoroughly discusses the biological functions of such lncRNAs in OSCC cell survival,proliferation,invasion,migration,metastasis,angiogenesis,metabolism,epigenetic modification,tumor immune microenvironment,and drug resistance.Subsequently,we addressed the diagnostic and therapeutic importance of lncRNAs in OSCC pre-clinical and clinical systems,providing details on ongoing research and outlining potential future directions for advancements in this field.In essence,this review could be a valuable resource by offering comprehensive and current insights into lncRNAs in OSCC for researchers in fundamental and clinical domains.

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.

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.

Functional role of long non-coding RNA CASC19/miR-140-5p/CEMIP axis in colorectal cancer progression in vitro

BACKGROUND Long non-coding RNAs(lncRNAs) are widely involved in tumor regulation.Nevertheless, the role of the lncRNA cancer susceptibility 19(CASC19) in colorectal cancer(CRC) has yet to be fully clarified.AIM To explore the effect of CASC19 on proliferation and metastasizing ability of CRC cells.METHODS CASC19 expression in human CRC tissues, pair-matched adjacent normal colon tissues, and CRC cells was detected using quantitative real-time PCR(qRT-PCR).CASC19 expression, as well as its relation to overall survival, was extrapolated by Kaplan-Meier survival analysis together with multivariable Cox regression assay.In vitro experiments were performed to confirm whether CASC19 regulates CRC cell invasion, migration, proliferation, and apoptosis.RESULTS CASC19 expression was markedly upregulated in CRC tissues and CRC cell lines(P < 0.05). qRT-PCR revealed that CASC19 expression was higher in 25 tissue samples from patients with aggressive CRC compared with the 27 tissue samples from patients with nonaggressive CRC(P < 0.05). Higher CASC19 expression was associated with poorer patient prognoses. Furthermore, in vitro experiments demonstrated that CASC19 overexpression enhanced CRC cell invasion,migration, and proliferation. CASC19 overexpression enhanced the expression of cell migration inducing hyaluronidase 1(CEMIP) and epithelial-mesenchymal transition markers. MiR-140-5 p was found to be able to bind directly to CASC19 and CEMIP. Overexpression of miR-140-5 p reversed the effect of CASC19 on cellproliferation and tumor migration, as well as suppressed CASC19-induced CEMIP expression.CONCLUSION CASC19 positively regulates CEMIP expression through targeting miR-140-5 p.CASC19 may possess an oncogenic function in CRC progression, highlighting its potential as an essential biomarker in CRC diagnosis and therapy.

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.

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.

HOTAIR:an oncogenic long non-coding RNA in different cancers

Long non-coding RNAs （lncRNAs） refer to a group of RNAs that are usually more than 200 nucleotides and are not involved in protein generation. Instead, lncRNAs are involved in different regulatory processes, such as regulation of gene expression. Different lncRNAs exist throughout the genome. LncRNAs are also known for their roles in different human diseases such as cancer. HOTAIR is an lncRNA that plays a role as an oncogenic molecule in different cancer ceils, such as breast, gastric, colorectal, and cervical cancer cells. Therefore, HOTAIR expression level is a potential biomarker for diagnostic and therapeutic purposes in several cancers. This RNA takes part in epigenetic regulation of genes and plays an important role in different cellular pathways by interacting with Polycomb Repressive Complex 2 （PRC2）. In this review, we describe the molecular function and regulation of HOTAIR and its role in different types of cancers.

Circulating micro RNAs and long non-coding RNAs in gastric cancer diagnosis:An update and review

Gastric cancer(GC) is the fourth most common cancer and the third leading cause of cancer mortality worldwide. Micro RNAs(mi RNAs) and long non-coding RNAs(lnc RNAs) are the most popular non-coding RNAs in cancer research. To date,the roles of mi RNAs and lnc RNAs have been extensively studied in GC,suggesting that mi RNAs and lnc RNAs represent a vital component of tumor biology. Furthermore,circulating mi RNAs and lnc RNAs are found to be dysregulated in patients with GC compared with healthy individuals. Circulating mi RNAs and lnc RNAs may function as promising biomarkers to improve the early detection of GC. Multiple possibilities for mi RNA secretion have been elucidated,including active secretion by microvesicles,exosomes,apoptotic bodies,highdensity lipoproteins and protein complexes as well as passive leakage from cells. However,the mechanism underlying lnc RNA secretion and the functions of circulating mi RNAs and lnc RNAs have not been fully illuminated. Concurrently,to standardize results of global investigations of circulating mi RNAs and lnc RNAs biomarker studies,several recommendations for preanalytic considerations are put forward. In this review,we summarize the known circulating mi RNAs and lnc RNAs for GC diagnosis. The possible mechanism of mi RNA and lnc RNA secretion as well as methodologies for identification of circulating mi RNAs and lnc RNAs are also discussed. The topics covered here highlight new insights into GC diagnosis and screening.

Value of long non-coding RNA Rpph1 in esophageal cancer and its effect on cancer cell sensitivity to radiotherapy

BACKGROUND Esophageal cancer is a common digestive tract tumor that is generally treated with radiotherapy.Poor responses to radiotherapy in most patients generally result in local radiotherapy failure,so it is essential to find new radiosensitizers that can enhance the response of cancer cells to radiotherapy and improve the survival of esophageal cancer patients with radiation resistance.The long noncoding RNA(lncRNA)Rpph1 is highly expressed in human gastric cancer tissues,and represses breast cancer cell proliferation and tumorigenesis.However,the expression of lncRNA Rpph1 in esophageal cancer and its relationship with radio-sensitivity has not been studied.AIM To explore the value of lncRNA Rpph1 in esophageal cancer and its effect on cancer cell sensitivity to radiotherapy.METHODS Eighty-three patients with esophageal cancer admitted to Qilu Hospital of Shandong University and 90 healthy participants who received physical examinations were collected as research participants.The expression of Rpph1 was determined by qRT-PCR.siRNA-NC and siRNA-Rpph1 were transfected into esophageal cancer cell lines,and cells without transfection were designated as the blank control group.Cell survival was tested by colony formation assays,and the levels of proteins related to apoptosis and epithelial-mesenchymal transitions were determined by Western blot assays.Cell proliferation was assessed by MTT assays,cell apoptosis by flow cytometry,and cell migration by wound-healing assays.Changes in cell cycle distribution were monitored.RESULTS Rpph1 was highly expressed in esophageal carcinoma,making it a promising marker for the diagnosis of esophageal cancer.Rpph1 could also be used to distinguish different short-term responses,T stages,N stages,and clinical stages of esophageal cancer patients.The results of 3-year overall survival favored patients with lower Rpph1 expression over patients with higher Rpph1 expression(P<0.05).In vitro and in vivo experiments showed that silencing Rpph1 expression led to higher sensitivity of esophageal cancer cells to radiotherapy,stronger apoptosis in esophageal cancer cells induced by radiotherapy,higher expression of Bax and caspase-3,and lower expression of Bcl-2(Bax,caspase-3,and Bcl-2 are apoptosis-related proteins).Additionally,silencing Rpph1 attenuated radiation-induced G2/M phase arrest,and significantly inhibited the expression of proteins involved in cell proliferation,migration,and epithelial-mesenchymal transition regulation in esophageal cancer cells.CONCLUSION Rpph1 is highly expressed in esophageal cancer.Silencing Rpph1 expression can promote cell apoptosis,inhibit cell proliferation and migration,and increase radio-sensitivity.

Behind the curtain of non-coding RNAs; long non-coding RNAs regulating hepatocarcinogenesis

Hepatocellular carcinoma(HCC) is one of the most common and aggressive cancers worldwide. HCC is the fifth common malignancy in the world and the second leading cause of cancer death in Asia. Long non-coding RNAs(lncRNAs) are RNAs with a length greater than 200 nucleotides that do not encode proteins. lncRNAs can regulate gene expression and protein synthesis in several ways by interacting with DNA, RNA and proteins in a sequence specific manner. They could regulate cellular and developmental processes through either gene inhibition or gene activation. Many studies have shown that dysregulation of lncRNAs is related to many human diseases such as cardiovascular diseases, genetic disorders, neurological diseases, immune mediated disorders and cancers. However, the study of lncRNAs is challenging as they are poorly conserved between species, their expression levels aren't as high as that of m RNAs and have great interpatient variations. The study of lncRNAs expression in cancers have been a breakthrough as it unveils potential biomarkers and drug targets for cancer therapy and helps understand the mechanism of pathogenesis. This review discusses many long non-coding RNAs and their contribution in HCC, their role in development, metastasis, and prognosis of HCC and how to regulate and target these lncRNAs as a therapeutic tool in HCC treatment in the future.

Identification of a five-long non-coding RNA signature to improve the prognosis prediction for patients with hepatocellular carcinoma

AIM To construct a long non-coding RNA(lnc RNA) signature for predicting hepatocellular carcinoma(HCC) prognosis with high efficiency.METHODS Differentially expressed lnc RNAs(DELs) between HCC specimens and peritumor liver specimens were identified using the edge R package to analyze The Cancer Genome Atlas(TCGA) LIHC dataset.Univariate Cox proportional hazards regression was performed to obtain the DELs significantly associated with overall survival(OS) in a training set.These OS-related DELs were further analyzed using a stepwise multivariate Cox regression model.Those lnc RNAs fitted in the multivariate Cox regression model and independently associated with overall survival were chosen to build a prognostic risk formula.The prognostic value ofthis formula was then validated in the test group and the entire cohort and further compared with two previously identified prognostic signatures for HCC.Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to explore the potential biological functions of the lnc RNAs in the signature.RESULTS Based on lnc RNA expression profiling of 370 HCC patients from the TCGA database,we constructed a 5-lnc RNA signature(AC015908.3,AC091057.3,TMCC1-AS1,DCST1-AS1 and FOXD2-AS1) that was significantly associated with prognosis.HCC patients with high-risk scores based on the expression of the 5 lnc RNAs had significantly shorter survival times compared to patients with low-risk scores in both the training and test groups.Multivariate Cox regression analysis demonstrated that the prognostic value of the 5 lnc RNAs was independent of clinicopathological parameters.A comparison study involving two previously identified prognostic signatures for HCC demonstrated that this 5-lnc RNA signature showed improved prognostic power compared with the other two signatures.Functional enrichment analysis indicated that the 5 lnc RNAs were potentially involved in metabolic processes,fibrinolysis and complement activation.CONCLUSION Our present study constructed a 5-lnc RNA signature that improves survival prediction and can be used as a prognostic biomarker for HCC patients.

Long Non-coding RNA MEG3 Induces Renal Cell Carcinoma Cells Apoptosis by Activating the Mitochondrial Pathway

Summary： This study aimed to examine the effect of long non-coding RNA （LncRNA） MEG3 on the biological behaviors of renal cell carcinoma （RCC） cells 786-0 and the possible mechanism. MEG3 expression levels were detected by RT-qPCR in Rmaor tissues and adjacent non-tumor tissues from 29 RCC patients and in RCC lines 786-0 and SN12 and human embryonic kidney cell line 293T. Plasmids GV144-MEG3 （MEG3 overexpression plasmid） and GV144 （control plasmid） were stably transfected into 786-0 cells by using lipofectamine 2000. Cell viabilities were determined by MTT, cell apoptosis rates by flow cytometry following PE Annexin V and 7AAD staining, apoptosis-related protein expressions by Western blotting, and Bcl-2 mRNA by RT-qPCR in the transfected cells. The results showed that MEG3 was evidently downregulated in RCC tissues （P〈0.05） and RCC cell lines （P〈0.05）. The viabilities of 786-0 cells were decreased significantly after transfection with GV144-MEG3 for over 24 h （P〈0.05）. Consistently, the apoptosis rate was significantly increased in 786-0 cells transfected with GV144-MEG3 for 48 h （P〈0.05）. Furthermore, overexpression of MEG3 could reduce the expression of Bcl-2 and procaspase-9 proteins, enhance the expression of cleaved caspase-9 protein, and promote the release of cytochrome c protein to cytoplasm （P〈0.05）. Additionally, Bcl-2 mRNA level was declined by MEG3 overexpression （P〈0.05）. It was concluded that MEG3 induces the apoptosis of RCC cells possibly by activating the mitochondrial pathway.