Long Noncoding RNA SNHG5 Induces the NF-κB Pathway by Regulating miR-181c-5p/CBX4 Axis to Promote the Progression of Non-Small Cell Lung Cancer

ObjectiveExplorations have been progressing in decoding the mechanism of non-small cell lung cancer (NSCLC). However, long noncoding RNA small nucleolar RNA host gene 5/microRNA-181c-5p/chromobox protein 4 (SNHG5/miR-181c-5p/CBX4) axis-oriented mechanisms in NSCLC is still in infancy. Therein, this study is proposed to probe this axis in NSCLC progression.MethodsSamples of 86 NSCLC patients were collected and SNHG5, miR-181c-5p and CBX4 expression was detected in NSCLC tissues and cells. NSCLC cells were transfected with plasmids to change SNHG5, miR-181c-5p or CBX4 expression, after which cell functions and phosphorylated (p)-nuclear factor (NF)-κB protein expression were evaluated. The relationships among SNHG5, miR-181c-5p and CBX4 were validated. Tumor xenografts were implemented to verify the roles of SNHG5, miR-181c-5p and CBX4 in tumor growth.ResultsLow miR-181c-5p and high SNHG5 and CBX4 levels were found in NSCLC tissues and cells. Restoration of miR-181c-5p or knockdown of SNHG5 or CBX4 restrained NSCLC cell progression and inactivated the NF-κB pathway. Upregulated CBX4 abolished the effects of miR-181c-5p on reducing NSCLC cell progression. SNHG5 regulated the interaction between miR-181c-5p and CBX4. In vivo, restoration of miR-181c-5p or knockdown of SNHG5 or CBX4 retarded the tumor growth.ConclusionThis study has delineated that SNHG5 induces the NF-κB pathway by regulating the miR-181c-5p/CBX4 axis to promote NSCLC progression, which may pave a novel path for NSCLC treatment.     

SNHG16 promotes hepatocellular carcinoma development via activating ECM receptor interaction pathway

Background:Accumulating data have suggested that long non-coding RNAs(lncRNAs)play important roles in regulating tumor cell growth.This study was designed to investigate the role of SNHG16 in hep-atocellular carcinoma(HCC).Methods:SNHG16 expression was detected with real-time polymerase chain reaction(PCR).The cut-offvalue of SNHG16 for tumor-free survival(TFS)was determined with receiver operating characteristic curve analysis.Small interfering RNA was used to inhibit the expression of SNHG16 in HCC cell lines.The biologic behavior of HCC cell was determined with cell viability assay and Transwell assay in vitro.The potential predictive value of SNHG16 on prognosis was analyzed by Kaplan-Meier curves and Cox proportional hazards regression model.Results:SNHG16 expression was upregulated in tumor tissues and HCC cell lines.High expression of SNHG16 was associated with tumor recurrence and poor prognosis after surgery.Multivariate analysis revealed that SNHG16 was an independent prognostic factor for poor recurrence-free survival.Moreover,inhibition of SNHG16 in HepG2,Hep3B,and BEL-7402 cells significantly reduced cell invasiveness and proliferation.Mechanistic analyses indicated that the ECM-receptor interaction pathway was remarkably activated by SNHG16.Conclusions:SNHG16 might be a promising biomarker for predicting tumor recurrence in HCC patients after surgery and a potential therapeutic target for HCC.     

lncRNA-SNHG15 accelerates the development of hepatocellular carcinoma by targeting mi R-490-3p/histone deacetylase 2 axis

BACKGROUND Hepatocellular carcinoma(HCC) has become a great threat for people's health.Many long noncoding RNAs are involved in the pathogenesis of HCC.SNHG15,as a tissue specific long noncoding RNAs,has been studied in many human cancers,except HCC.AIM To explore the regulatory mechanism of SNHG15 in HCC METHODS In the present research,101 HCC patient samples,two HCC cell lines and one normal liver cell line were used.RT-qPCR and Western blot analysis were applied to detect SNHG15,miR-490-3 p and histone deacetylase 2(HD AC2)expression.The regulatory mechanism of SNHG15 was investigated using CCK8,Transwell and luciferase reporter assays.RESULTS Our research showed that up-regulation of SNHG15 was found in HCC and was related to aggressive behaviors in HCC patients.Moreover,knockdown of SNHG15 restrained HCC cell proliferation,migration and invasion.In addition,SNHG15 served as a molecular sponge for miR-490-3 p.Further,miR-490-3 p directly targets HDAC2.HD AC2 was involved in HCC progression by interacting with the SNHG15/miR-490-3 p axis.CONCLUSION In conclusion,long noncoding RNA SNHG15 promotes HCC progression by mediating the miR-490-3 p/HDAC2 axis in HCC.     

非编码RNA在分化型甲状腺癌分子诊断中的作用

分化型甲状腺癌占全部甲状腺癌的90％以上,主要包括乳头状癌和滤泡状癌.目前,细针穿刺抽吸活检是术前诊断甲状腺肿瘤的金标准,但仍存在一定的局限性,且临床上尚无理想的分子标志物用于确诊.非编码RNA是无蛋白编码功能的RNA,主要包括微小RNA (miRNA)和长链非编码RNA (lncRNA),二者在甲状腺癌的发生、发展中起重要作用,其在分化型甲状腺癌分子诊断中的作用日益受到人们的关注,有望成为甲状腺癌诊断与分类的理想标志物.     

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

Long noncoding RNAs(lnc RNAs) and micro RNAs(mi RNAs) are noncoding RNAs(nc RNAs) that occupy over 90% of the human genome, and their main function is to directly or indirectly regulate messenger RNA(m RNA) expression and participate in the tumorigenesis and progression of malignances. In particular, some lnc RNAs can interact with mi RNAs as competing endogenous RNAs(ce RNAs) to modulate m RNA expression. Accordingly, these RNA molecules are interrelated and coordinate to form a dynamic lnc RNA-mediated ce RNA regulatory network. Mounting evidence has revealed that lnc RNAs that act as ce RNAs are closely related to tumorigenesis. To date, numerous studies have established many different regulatory networks in hepatocellular carcinoma(HCC), and perturbations in these ce RNA interactions may result in the initiation and progression of HCC. Herein, we emphasize recent advances concerning the biological function of lnc RNAs as ce RNAs in HCC, with the aim of elucidating the molecular mechanism underlying these HCC-related RNA molecules and providing novel insights into the diagnosis and treatment of HCC.     

长链非编码核仁小分子RNA宿主基因1对类风湿关节炎成纤维样滑膜细胞增殖的影响

目的 初步探讨长链非编码核仁小分子RNA宿主基因1(SNHG1)对RA-成纤维样滑膜细胞(FLS)增殖的影响及可能的机制.方法 组织块培养法培养RA和创伤患者FLS,用实时荧光定量PCR(qPCR)法检测二者SNHG1的表达情况;在RA-FLS中,用小干扰RNA(siRNA)沉默SNHG1表达后,CCK-8法检测细胞增殖活力,流式细胞术检测细胞周期分布,蛋白质印迹法检测周期蛋白(cyclin)D1的表达情况;2组样本比较用独立样本t检验,多组样本间比较采用单因素方差分析.结果 与创伤患者FLS相比,RA-FLS中SNHG1表达上调[(2.13±0.55)与(1.00±0.01)](t=-5.87,P=0.004);在RA-FLS中,沉默SNHG1表达后,与阴性对照相比,SNHG1-siRNA处理组细胞增殖活力下调[(0.930±0.033)与(0.759±0.027)](t=6.879,P=0.002),G2/M+S期细胞所占比例下调[(28.2±1.5)%与(9.7±2.6)%](t=10.715,P<0.01),cyclinD1蛋白表达下调(t=6.168,P=0.004).结论 RA患者滑膜细胞中SNHG1的表达增高,SNHG1可能通过影响cyclinD1蛋白表达参与FLS增殖调控,从而促进滑膜增生.     

RNA interference in mammalian cell systems

In the last decade, few areas of biology have been transformed as thoroughly as RNA molecular biology. Without any doubt, one of the most significant advances has been the discovery of small (20-30 nucleotide) noncoding RNAs that regulate genes and genomes. The effects of small RNAs on gene expression and control are generally inhibitory, and the corresponding regulatory mechanisms are therefore collectively subsumed under the heading of RNA silencing and/or RNA interference. Two primary categories of these small RNAs - short interfering RNAs (siRNAs) and microRNAs (miRNAs) - act in both somatic and germline lineages of eukaryotic species to regulate endogenous genes and to defend the genome from invasive nucleic acids. Recent advances have revealed unexpected diversity in their biogenesis pathways and the regulatory mechanisms that they access. Our understanding of siRNA and miRNA-based regulation has direct implications for fundamental biology as well as disease aetiology and treatment as it is discussed in this review on 'new techniques in molecular biology'.     

Long non-coding RNA SNHG16 as a potential biomarker in hepatocellular carcinoma: A meta-analysis

Small nucleolar RNA host gene 16 (SNHG16) has recently been reported as a potential biomarker in various cancers. However, the prognostic value of SNHG16 in hepatocellular carcinoma (HCC) has not been investigated yet. Therefore, the purpose of this study was to reveal the association between SNHG16 expression and clinicopathological characteristics of HCC.Standards-compliant literature was retrieved from multiple public databases, and data on overall survival, disease-free survival, and clinicopathological characteristics related to SNGH16 were extracted and meta-analysis was performed. Additionally, the Cancer Genome Atlas data were analyzed through the gene expression profiling interactive analysis database to verify previous results.A total of 5 reports involving 410 patients with HCC were enrolled. The high expression of SNHG16 indicated worse overall survival (hazard ratio, 2.10; 95% CI, 1.22–3.60; P = .007) and disease-free survival (hazard ratio, 3.38; 95% CI, 1.10–10.40; P = .03). Additionally, the high expression of SNHG16 predicted a larger tumor size, metastasis, and advanced TNM stage.SNHG16 could serve as a potential biomarker of poor prognosis in HCC.     

MicroRNA and gene expression analysis of melatonin-exposed human breast cancer cell lines indicating involvement of the anticancer effect

MicroRNAs (miRNAs) are small, noncoding RNAs that play a crucial role in regulation of gene expression. Recent studies have shown that miRNAs implicated in initiation and progression of various human cancers, including breast cancer and also analysis of miRNA expression profiles in cancer provide new insights into potential mechanisms of carcinogenesis. Melatonin, N-acetyl-5-methoxytryptamine, is synthesized by the pineal gland in response to the dark/light cycle and has been known to act as a synchronizer of the biological clock. Melatonin has a variety of therapeutic effects, such as immunomodulatory actions, anti-inflammatory effects, and antioxidant actions. Furthermore, melatonin is reported to have an anticancer function including suppression of the metabolism of tumor cells and induction of tumor suppressor genes in cancer cells, including breast cancer cells. In this study, we determined whether miRNAs play a role in regulation of various gene expression responses to melatonin in MCF-7 human breast cancer cells. We examined whole-genome miRNA and mRNA expression and found that 22 miRNAs were differentially expressed in melatonin-treated MCF-7 cells. We further identified a number of mRNAs whose expression level shows a high inverse correlation with miRNA expression. The Gene Ontology (GO) enrichment analysis and pathways analysis were performed for identification of the signaling pathways and biological processes affected by differential expression of miRNA and miRNA-related genes. Our findings suggested that melatonin may modulate miRNA and gene expression as an anticancer mechanism in human breast cancer cells.     

Circulating RNAs as new biomarkers for detecting pancreatic cancer

Pancreatic cancer remains difficult to treat and has a high mortality rate. It is difficult to diagnose early, mainly due to the lack of screening imaging modalities and specific biomarkers. Consequently, it is important to develop biomarkers that enable the detection of early stage tumors. Emerging evidence is accumulating that tumor cells release substantial amounts of RNA into the bloodstream that strongly resist RNases in the blood and are present at sufficient levels for quantitative analyses. These circulating RNAs are upregulated in the serum and plasma of cancer patients, including those with pancreatic cancer, compared with healthy controls. The majority of RNA biomarker studies have assessed circulating microRNAs (miRs), which are often tissue-specific. There are few reports of the tumor-specific upregulation of other types of small non-coding RNAs (ncRNAs), such as small nucleolar RNAs and Piwi-interacting RNAs. Long ncRNAs (lncRNAs), such as HOTAIR and MALAT1, in the serum/plasma of pancreatic cancer patients have also been reported as diagnostic and prognostic markers. Among tissue-derived RNAs, some miRs show increased expression even in pre-cancerous tissues, and their expression profiles may allow for the discrimination between a chronic inflammatory state and carcinoma. Additionally, some miRs and lncRNAs have been reported with significant alterations in expression according to disease progression, and they may thus represent potential candidate diagnostic or prognostic biomarkers that may be used to evaluate patients once detection methods in peripheral blood are well established. Furthermore, recent innovations in high-throughput sequencing techniques have enabled the discovery of unannotated tumor-associated ncRNAs and tumor-specific alternative splicing as novel and specific biomarkers of cancers. Although much work is required to clarify the release mechanism, origin of tumor-specific circulating RNAs, and selectivity of carrier complexes, and technical advances must also be achieved, such as creating a consensus normalization protocol for quantitative data analysis, circulating RNAs are largely unexplored and might represent novel clinical biomarkers.     

An intrinsically disordered C terminus allows the La protein to assist the biogenesis of diverse noncoding RNA precursors

The La protein binds the 3' ends of many newly synthesized noncoding RNAs, protecting these RNAs from nucleases and influencing folding, maturation, and ribonucleoprotein assembly. Although 3' end binding by La involves the N-terminal La domain and adjacent RNA recognition motif (RRM), the mechanisms by which La stabilizes diverse RNAs from nucleases and assists subsequent events in their biogenesis are unknown. Here we report that a conserved feature of La proteins, an intrinsically disordered C terminus, is required for the accumulation of certain noncoding RNA precursors and for the role of the Saccharomyces cerevisiae La protein Lhp1p in assisting formation of correctly folded pre-tRNA anticodon stems in vivo. Footprinting experiments using purified Lhp1p reveal that the C terminus is required to protect a pre-tRNA anticodon stem from chemical modification. Although the C terminus of Lhp1p is hypersensitive to proteases in vitro, it becomes protease-resistant upon binding pre-tRNAs, U6 RNA, or pre-5S rRNA. Thus, while high affinity binding to 3' ends requires the La domain and RRM, a conformationally flexible C terminus allows La to interact productively with a diversity of noncoding RNA precursors. We propose that intrinsically disordered domains adjacent to well characterized RNA-binding motifs in other promiscuous RNA-binding proteins may similarly contribute to the ability of these proteins to influence the cellular fates of multiple distinct RNA targets.     

microRNA与肾上腺皮质肿瘤

microRNA(miRNA)是一类非编码小分子RNA,通过转录后机制抑制基因表达.其表达水平的异常和肿瘤的发生、发展关系密切.许多研究表明,异常表达的miRNA影响肾上腺皮质细胞的增殖、凋亡及功能,可作为良、恶性肾上腺皮质肿瘤的生物标志物.     

Epigenetics: An emerging player in gastric cancer

Cancers,like other diseases,arise from gene mutations and/or altered gene expression,which eventually cause dysregulation of numerous proteins and noncoding RNAs.Changes in gene expression,i.e.,upregulation of oncogenes and/or downregulation of tumor suppressor genes,can be generated not only by genetic and environmental factors but also by epigenetic factors,which are inheritable but nongenetic modifications of cellular chromosome components.Identification of the factors that contribute to individual cancers is a prerequisite to a full understanding of cancer mechanisms and the development of customized cancer therapies.The search for genetic and environmental factors has a long history in cancer research,but epigenetic factors only recently began to be associated with cancer formation,progression,and metastasis.Epigenetic alterations of chromatin include DNA methylation and histone modifications,which can affect gene-expression profiles.Recent studies have revealed diverse mechanisms by which chromatin modifiers,including writers,erasers and readers of the aforementioned modifications,contribute to the formation and progression of cancer.Furthermore,functional RNAs,such as microRNAs and long noncoding RNAs,have also been identified as key players in these processes.This review highlights recent findings concerning the epigenetic alterations associated with cancers,especially gastric cancer.     

Long noncoding RNA RP4 functions as a competing endogenous RNA through miR-7-5p sponge activity in colorectal cancer

AIM To investigate the role of long noncoding RNA(lnc RNA) RP4 in colorectal cancer.METHODS Lentivirus-mediated lnc RNA RP4 overexpression and knockdown were performed in the colorectal cancer cell line SW480. Cell proliferation, tumor growth, and early apoptosis were evaluated by a cell counting kit-8 assay, an in vivo xenograft tumor model, and annexin V/propidium iodide staining, respectively. Analysis of the lnc RNA RP4 mechanism involved assessment of the association of its expression with mi R-7-5 p and the SH3 GLB1 gene. Western blot analysis was also performed to assess the effect of lnc RNA RP4 on the autophagy-mediated cell death pathway and phosphatidylinositol-3-kinase(PI3 K)/Akt signaling.RESULTS Cell proliferation, tumor growth, and early apoptosis in SW480 cells were negatively regulated by lnc RNA RP4. Functional experiments indicated that lnc RNA RP4 directly upregulated SH3 GLB1 expression by acting as a competing endogenous RNA(ce RNA) for mi R-7-5 p. This interaction led to activation of the autophagy-mediated cell death pathway and de-repression of PI3 K and Akt phosphorylation in colorectal cancer cells in vivo.CONCLUSION Our results demonstrated that lnc RNA RP4 is a ce RNA that plays an important role in the pathogenesis of colorectal cancer, and could be a potential therapeutic target for colorectal cancer treatment.