Genome-wide analyses of long noncoding RNA expression profiles in lung adenocarcinoma

NCK1-AS1 promotes the proliferation, migration, invasion, and EMT of non-small cell lung cancer by regulating the miR-361-5p/ADAM10 axis

Lung cancer, one of the most frequently diagnosed cancers, causes a huge number of mortalities globally. Among lung cancers, non-small cell lung cancer (NSCLC) is the most recorded. Despite accumulating research, the molecular basis of NSCLC progression remains poorly known. Therefore, we aim to assess the function of NCK1-AS1 in NSCLC and elucidate the molecular mechanism. Firstly, we quantified the NCK1-AS1 level in tumors and adjacent healthy tissues. NCK1-AS1 was significantly upregulated in NSCLC tumors, which was associated with poor prognosis in patients. Silencing NCK1-AS1 significantly inhibited the proliferation, migration, and invasion, as well as the EMT of NSCLC cell lines. Starbase bioinformatic prediction revealed that NCK1-AS1 targets miR-361-5p which acts to regulate ADAM10 gene expression. Our result showed that NCK1-AS1 upregulation markedly reduced miR-361-5p mRNA expression, while increasing ADAM10 expression. For the first time, we demonstrated that NCK1-AS1 regulates the miR-361-5p/ADAM10 axis, thereby promoting NSCLC progression. NCK1-AS1 might be developed as a therapeutic target for treating NSCLC.

Circadian gene ARNTL initiates circGUCY1A2 transcription to suppress non-small cell lung cancer progression via miR-200c-3p/PTEN signaling

BACKGROUND

As a subclass of endogenous stable noncoding RNAs, circular RNAs are beginning to be appreciated for their potential as tumor therapeutics. However, the functions and mechanisms by which circRNAs exert protective functions in non-small cell lung cancer (NSCLC) remain largely elusive.

METHODS

The prognostic role of circGUCY1A2 was explored in lung adenocarcinoma specimens. The overexpressed and knockdown plasmids were used to evaluate the effect of circGUCY1A2 on NSCLC cell proliferation and apoptosis efficacy. Luciferase reporter system is used to prove that circGUCY1A2 could bind to miRNA. Chip-PCR was used to prove that circGUCY1A2 could be initiated by transcription factors ARNTL. Subcutaneous tumorigenicity grafts models were established to validate findings in vivo.

RESULTS

The expression of circGUCY1A2 were significantly reduced (P < 0.001) and negatively correlated with tumor size (P < 0.05) in non-small cell lung cancer (NSCLC). CircGUCY1A2 upregulation promoted apoptosis and inhibits cell proliferation and growth of subcutaneous tumorigenicity grafts in nude mice (P < 0.01). In addition, intra-tumor injection of pLCDH-circGUCY1A2 inhibited tumor growth in patient-derived NSCLC xenograft models (PDX). Mechanism studies showed that circGUCY1A2 could act as a sponge to competitively bind miR-200c-3p, promote PTEN expression, and thereby inhibit PI3K/AKT pathway. In addition, we found that the circadian gene ARNTL, which was reduced in NSCLC and prolonged the overall survival of patients, could bind to the promoter of circGUCY1A2, thereby increasing its expression.

CONCLUSIONS

This study is an original demonstration that ARNTL can inhibit the development of lung adenocarcinoma through the circGUCY1A2/miR-200c-3p/PTEN axis, and this finding provides potential targets and therapeutic approaches for the treatment of lung adenocarcinoma.

N6-methyladenosine-induced SVIL antisense RNA 1 restrains lung adenocarcinoma cell proliferation by destabilizing E2F1

Accumulating evidence indicates that N6-methyladenosine (m6A) and long noncoding RNAs (lncRNAs) play crucial roles in cancer development. However, the biological roles of m6A and lncRNAs in lung cancer tumorigenesis are largely unknown. In this study, SVIL antisense RNA 1 (SVIL-AS1) was downregulated in lung adenocarcinoma (LUAD) tissues and was associated with a favorable prognosis in patients with LUAD. SVIL-AS1 overexpression suppressed LUAD cell proliferation and blocked cell cycle arrest. Mechanistically, METTL3 increased the m6A modification and transcript stability of SVIL-AS1. The enhanced SVIL-AS1 expression mediated by METTL3 suppressed E2F1 and E2F1-target genes. Moreover, SVIL-AS1 accelerated E2F1 degradation. The reduction in cell proliferation induced by SVIL-AS1 overexpression could be rescued by E2F1 overexpression or METTL3 knockdown. In conclusion, our work demonstrated the role and mechanism of METTL3-induced SVIL-AS1 in LUAD, which connects m6A and lncRNA in lung cancer carcinogenesis.

Lateral flow assay-based detection of long non-coding RNAs: A point-of-care platform for cancer diagnosis

Lateral flow assay (LFA) is a flexible, simple, low-costpoint-of-care platform for rapid detection of disease-specific biomarkers. Importantly, the ability of the assay to capture the circulating bio-molecules has gained significant attention, as it offers a potential minimal invasive system for early disease diagnosis and prognosis. In the present article, we review an innovative concept of LFA-based detection of circulating long non-coding RNAs (lncRNAs), one of the key regulators of fundamental biological processes. In addition, their disease-specific expression pattern and presence in biological fluids at differential levels make them excellent biomarker candidates for cancer detection. Our article also provides an update on the requirements for developing and improving such systems and discusses the key aspects of material selection, operational concepts, principles and conceptual design. We assume that the reviewed points will be helpful to improve the diagnostic applicability of LFA based lncRNA detection in cancer diagnosis.

Comprehensive Analysis of Differentially Expressed Long Noncoding RNA-mRNA in the Adenoma-Carcinoma Sequence of DNA Mismatch Repair Proficient Colon Cancer

DNA proficient mismatch repair colon cancer (pMMR CC) is the most common subtype of sporadic CC. We aimed to investigate the role of long noncoding RNAs (lncRNAs) in pMMR CC carcinogenesis. In the present study, we conducted transcriptomic analysis of lncRNAs-mRNAs in five low-grade intraepithelial neoplasia (LGIN), five high-grade intraepithelial neoplasia (HGIN), four pMMR CC, and five normal control (NC) tissues. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway, and coexpression network analyses were performed to elucidate the functions of lncRNAs and mRNAs as well as their interactions. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to validate five dysregulated lncRNAs in a large set of colon tissues. Receiver-operating characteristic (ROC) curves were employed to evaluate the performance of the candidate lncRNAs. A set of 5783 differentially expressed lncRNAs and 4483 differentially expressed mRNAs were detected among the LGIN, HGIN, pMMR CC, and NC samples. These differentially expressed lncRNAs and mRNAs were assigned to 275 significant GO terms and 179 significant KEGG enriched pathways. qRT-PCR confirmed that the expression of five selected lncRNAs (ENST00000521815, ENST00000603052, ENST00000609220, NR_026543, and ENST00000545920) were consistent with the microarray data. ROC analysis showed that four lncRNAs (ENST00000521815, ENST00000603052, ENST00000609220, and NR_026543) had larger area under the ROC curve (AUC) values compared to serum carcinoembryonic antigens, thereby distinguishing NC from pMMR CC. In conclusion, several lncRNAs play various roles in the adenoma-carcinoma sequence and may serve as potential biomarkers for the early diagnosis of pMMR CC.

Prognostic Signature for Lung Adenocarcinoma Patients Based on Cell-Cycle-Related Genes

Objective

To screen lung adenocarcinoma (LUAC)-specific cell-cycle-related genes (CCRGs) and develop a prognostic signature for patients with LUAC.

Methods

The GSE68465, GSE42127, and GSE30219 data sets were downloaded from the GEO database. Single-sample gene set enrichment analysis was used to calculate the cell cycle enrichment of each sample in GSE68465 to identify CCRGs in LUAC. The differential CCRGs compared with LUAC data from The Cancer Genome Atlas were determined. The genetic data from GSE68465 were divided into an internal training group and a test group at a ratio of 1:1, and GSE42127 and GSE30219 were defined as external test groups. In addition, we combined LASSO (least absolute shrinkage and selection operator) and Cox regression analysis with the clinical information of the internal training group to construct a CCRG risk scoring model. Samples were divided into high- and low-risk groups according to the resulting risk values, and internal and external test sets were used to prove the validity of the signature. A nomogram evaluation model was used to predict prognosis. The CPTAC and HPA databases were chosen to verify the protein expression of CCRGs.

Results

We identified 10 LUAC-specific CCRGs (PKMYT1, ETF1, ECT2, BUB1B, RECQL4, TFRC, COCH, TUBB2B, PITX1, and CDC6) and constructed a model using the internal training group. Based on this model, LUAC patients were divided into high- and low-risk groups for further validation. Time-dependent receiver operating characteristic and Cox regression analyses suggested that the signature could precisely predict the prognosis of LUAC patients. Results obtained with CPTAC, HPA, and IHC supported significant dysregulation of these CCRGs in LUAC tissues.

Conclusion

This prognostic prediction signature based on CCRGs could help to evaluate the prognosis of LUAC patients. The 10 LUAC-specific CCRGs could be used as prognostic markers of LUAC.

Heat shock protein B8 promotes proliferation and migration in lung adenocarcinoma A549 cells by maintaining mitochondrial function

Heat shock protein B8 (HSPB8) impacts on tumor proliferation and migration of malignancy. However, the role of HSPB8 in lung adenocarcinoma (LUAC) remains unclear. The aim of this study, therefore, was to clarify whether HSPB8 could bring benefits to proliferation and migration of LUAC and its underlying mechanisms. The expression of HSPB8 was first evaluated by immunohistochemistry in 35 LUAC samples. Then, A549 lung adenocarcinoma cells were transfected with pcDNA-HSPB8 or si-HSPB8 to induce HSPB8 overexpression and silence. Cellular activity was evaluated with a Cell Counting Kit-8 (CCK-8) assay. Cell proliferation and migration were observed by EdU assay and scratch assay. Mitochondria-specific reactive oxygen species (mtROS) and membrane potential were measured using MitoSOX Red probe and JC-1 staining. Superoxide dismutase (SOD) activities and malondialdehyde (MDA) level were measured using commercial kits, respectively. HSPB8 protein, mitochondrial fusion protein MFN2 and mitochondrial fission protein p-Drp1/Drp1 were measured using western blot. Compared with the normal tissues, the expression of HSPB8 protein was higher in LUAC tissues and upregulation of HSPB8 protein was related to tumor size and tumor location. Furthermore, HSPB8 overexpression aggravated cell proliferation and migration of A549 cells. Mechanistically, HSPB8 suppressed mitochondrial impairment, leading to promoting the progress of A549 lung adenocarcinoma cells. These data demonstrate that HSPB8 plays an important role in progression of LUAC and may be a new target to treat LUAC.

Comprehensive Analysis of Candidate Diagnostic and Prognostic Biomarkers Associated with Lung Adenocarcinoma

Background

We aimed to screen and identify central genetic and molecular targets involved in advancement of lung adenocarcinoma (LUAD) and to perform an integrated analysis and clinical validation.

Material/Methods

The GEO2R technique was utilized to assess differentially expressed genes (DEGs) among the gene sets GSE75037, GSE85716, and GSE118370. Subsequently, gene Ontology (GO) analyses and Kyoto Encyclopedia of Genes and Genomes (KEGG) analytical methods were executed to determine related biofunctions and signaling pathways, which were annotated with tools from the Database for Annotation, Visualization and Integrated Discovery (DAVID) resource. Then, a protein-protein interaction (PPI) network complex consisting of all detected DEGs was built with the STRING web interface. Cytohubba and MCODE plug-ins for Cytoscape software and Gene Expression Profiling Interactive Analysis (GEPIA) were employed to identify the hub genes. Finally, the mRNA expression of the identified hub genes was quantitatively validated by The Cancer Genome Atlas (TCGA) database analysis and real-time quantitative polymerase chain reaction (RT-qPCR).

Results

We screened 146 upregulated DEGs and 431 downregulated DEGs with the criteria of |logFC| >1 and P<0.05, and the GO analysis indicated that DEGs were implicated in mitotic nuclear division (biological process, BP), the nucleus (cellular component, CC), and protein binding (molecular function, MF) and were associated with multiple KEGG pathways, such as the p53 signaling pathway in cancer. Then, the top 8 genes that predicted significantly different outcomes in LUAD patients were filtered from the DEGs and selected as hub genes. The TCGA database analysis and RT-qPCR results demonstrated that these genes were differentially expressed with the same trends in LUAD tissues compared with normal tissues.

Conclusions

Overall, we propose that 8 genes (PECAM1, CDK1, MKI67, SPP1, TOP2A, CHEK1, CCNB1, and RRM2) might be novel hub genes strongly associated with the progression and prognosis of LUAD.

Long non-coding RNAs: How to regulate the metastasis of non-small-cell lung cancer

Non–small‐cell lung cancer (NSCLC) has become the most lethal human cancer because of the high rate of metastasis. Hence, clarifying the molecular mechanism underlying NSCLC metastasis is very important to improve the prognosis of patients with NSCLC. Long non‐coding RNAs (LncRNAs) are a class of RNA molecules longer than 200 nucleotides, which can participate in diverse biological processes. About 18% of human LncRNAs were recently found to be associated with tumours. Many studies indicated that aberrant expression of LncRNAs played key roles in the progression and metastasis of NSCLC. According to the function in tumours, LncRNAs can be divided into two classes: oncogenic LncRNAs and tumour‐suppressor LncRNAs. In this review, we summarized the main molecular mechanism of LncRNAs regulating NSCLC metastasis, including three aspects: (a) LncRNAs interact with miRNAs as ceRNAs; (b) LncRNAs bind with target proteins; and (c) LncRNAs participate in the transduction of different signal pathways. Then, LncRNAs can exert their function to regulate the metastasis of NSCLC through influencing the progression of epithelial‐mesenchymal transition (EMT) and the properties of cancer stem cell (CSC). But, it is necessary to do some further research to demonstrate the LncRNAs particular regulatory mechanism of inhibiting the metastasis of NSCLC and explore new drugs targeting LncRNAs.

Genome-wide analysis reveals the emerging roles of long non-coding RNAs in cancer

Cancer is the most intractable human disease that is primarily caused by genetic alterations. Recently, the general application of microarrays and high-throughput sequencing technology has revealed various important roles of long noncoding RNAs (lncRNAs) in cancer. This review summarizes the function, mechanism, diagnostic and treatment potential of lncRNAs identified through genome-wide analysis in cancer. Cell-, tissue- and development stage-specific expression patterns are major characteristics of cancer-associated lncRNAs, and various genetic alterations are also implicated. Microarray and sequencing analyses serve important roles in mechanistic studies of either nuclear or cytoplasmic lncRNAs. Collectively, genome-wide analysis is the inexorable trend of future studies or clinical applications of lncRNAs and offers a novel perspective regarding the prognosis and treatment of cancer.

Are Long Noncoding RNAs New Potential Biomarkers in Gastrointestinal Stromal Tumors (GISTs)? The Role of H19 and MALAT1

Long noncoding RNAs (lncRNAs) are emerging as key regulators of genetic and epigenetic networks, and their deregulation may underlie complex diseases, such as carcinogenesis. Several studies described lncRNA alterations in patients with solid tumors. In particular, HOTAIR upregulation has been associated with tumor aggressiveness, metastasis, and poor survival in gastrointestinal stromal tumor (GIST) patients. We analyzed expression levels of other lncRNAs, H19 and MALAT1, in FFPE tissue specimens from 40 surgically resected and metastatic GIST patients, using real-time PCR analysis. H19 and MALAT1 were both upregulated in 50% of GIST patients. MALAT1 lncRNA expression levels seem to be correlated with c-KIT mutation status. The percentage of both H19 and MALAT1 upregulation was significantly higher in patients with time to progression (TTP) < 6 months as compared to patients with TTP > 6 months. The median TTP was significantly lower in patients with both H19 and MALAT1 lncRNA upregulation as compared to those with lncRNA downregulation. These data suggest a potential role for both H19 and MALAT1 lncRNAs as prognostic biomarker for the clinical selection of the best candidate to first-line treatment with imatinib.

LINC81507 act as a competing endogenous RNA of miR-199b-5p to facilitate NSCLC proliferation and metastasis via regulating the CAV1/STAT3 pathway

Lung cancer is the leading cause of cancer-related mortality worldwide. Recently, accumulating data indicate that long noncoding RNAs (LncRNAs) function as novel crucial regulators of diverse biological processes, including proliferation and metastasis, in tumorigenesis. Lnc NONHSAT081507.1 (LINC81507) is associated with lung adenocarcinoma. However, its pathological role in non-small cell lung cancer (NSCLC) remains unknown. In our study we investigated the role of LINC81507 in NSCLC. The expression of LINC81507 was analyzed in 105 paired NSCLC tumor specimens and paired adjacent non-tumorous tissues from NSCLC patients by real-time quantitative PCR (RT-qPCR). Gain- and loss-of-function experiments were conducted to investigate the functions of LINC81507, miR-199b-5p and CAV1. Reduced expression of LINC81507 resulted in cell growth, proliferation, migration and epithelial–mesenchymal transition (EMT) in NSCLC cells, whereas ectopic overexpression of LINC81507 resulted in the opposite effects both in vitro and in vivo. Nuclear and Cytoplasmic fractionation assays showed LINC81507 mainly resided in cytoplasm. Bioinformatics analysis and dual-luciferase assays revealed that miR-199b-5p was a direct target of LINC81507 through binding Ago2. Mechanistic analysis demonstrated that miR-199b-5p specifically targeted the Caveolin1 (CAV1) gene, and LINC81507 inactivated the STAT3 pathway in a CAV1-dependent manner. Taken together, LINC81507 is decreased in NSCLC and functions as a sponge to miR-199b-5p to regulate CAV1/STAT3 pathway, which suggests that LINC81507 serve as a tumor suppressor and potential therapeutic target and biomarker for metastasis and prognosis in NSCLC.

Microarray analysis of infectious bronchitis virus infection of chicken primary dendritic cells

Background

Avian infectious bronchitis virus (IBV) is a major respiratory disease-causing agent in birds that leads to significant losses. Dendritic cells (DCs) are specialised cells responsible for sampling antigens and presenting them to T cells, which also play an essential role in recognising and neutralising viruses. Recent studies have suggested that non-coding RNAs may regulate the functional program of DCs. Expression of host non-coding RNAs changes markedly during infectious bronchitis virus infection, but their role in regulating host immune function has not been explored. Here, microarrays of mRNAs, miRNAs, and lncRNAs were globally performed to analyse how avian DCs respond to IBV.

Results

First, we found that IBV stimulation did not enhance the maturation ability of avian DCs. Interestingly, inactivated IBV was better able than IBV to induce DC maturation and activate lymphocytes. We identified 1093 up-regulated and 845 down-regulated mRNAs in IBV-infected avian DCs. Gene Ontology analysis suggested that cellular macromolecule and protein location (GO-BP) and transcription factor binding (GO-MF) were abundant in IBV-stimulated avian DCs. Meanwhile, pathway analysis indicated that the oxidative phosphorylation and leukocyte transendothelial migration signalling pathways might be activated in the IBV group. Moreover, alteration of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) was detected in IBV-stimulated avian DCs. In total, 19 significantly altered (7 up and 12 down) miRNAs and 101 (75 up and 26 down) lncRNAs were identified in the IBV-treated group. Further analysis showed that the actin cytoskeleton and MAPK signal pathway were related to the target genes of IBV-stimulated miRNAs. Finally, our study identified 2 TF-microRNA and 53 TF–microRNA–mRNA interactions involving 1 TF, 2 miRNAs, and 53 mRNAs in IBV-stimulated avian DCs.

Conclusions

Our research suggests a new mechanism to explain why IBV actively blocks innate responses needed for inducing immune gene expression and also provides insight into the pathogenic mechanisms of avian IBV.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5940-6) contains supplementary material, which is available to authorized users.

Upregulated LncRNA-CCAT1 promotes hepatocellular carcinoma progression by functioning as miR-30c-2-3p sponge

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death over the world. It is well studied that long noncoding RNA colon cancer-associated transcript-1 (CCAT1) played important roles in variety of cancers promoting cell proliferation and metastasis by acting as a competing endogenous RNA (ceRNA) of microRNAs. However, whether CCAT1 could regulate HCC by serving as a ceRNA of microRNA remains to be revealed. In this study, we demonstrated that CCAT1 was highly expressed in HCC tissues and remarkably associated with metastasis. With a bioinformatics prediction and functional assay validation, we found a binding site of miR-30c-2-3p on CCAT1, which was important for CCAT1 to promote cell proliferation. Interestingly, we further revealed a novel recognition site for miR-30c-2-3p on the 3'UTR of CCNE1 by mutative method, luciferase assay, and cell viability confirmation. In general, CCAT1 regulate the expression of CCNE1 by acting as a ceRNA to sponge miR-30c-2-3p in regulating the cell proliferation of HCC. These results suggest that CCAT1 may be a new therapy target for HCC in the future. SIGNIFICANCE OF THE STUDY: Our findings may broaden the understanding of the role of CCAT1 in tumorigenesis and may provide a new therapy target for HCC.

The long noncoding RNA LINC00312 induces lung adenocarcinoma migration and vasculogenic mimicry through directly binding YBX1

Vasculogenic mimicry (VM) gives rise to tumor neovascularization that is critical for tumor growth and metastasis. Long non-coding RNAs (lncRNAs) have been implicated in diverse and fundamental biological processes. LINC00312 is associated with lung adenocarcinoma. In this study, we found that LINC00312 induced migration, invasion and VM of lung cancer cells by direct binding to the transcription factor Y-Box Binding Protein 1 (YBX1). Moreover, we demonstrated that YBX1 is associated with different fragments within 0-2410 nt 5'region of LINC00312. In addition, LINC00312 is associated with VM in 124 lung adenocarcinoma clinical specimens. The results suggest that LINC00312 is a promising therapeutic and diagnostic target for lung adenocarcinoma.

Uncovering association networks through an eQTL analysis involving human miRNAs and lincRNAs

Non-coding RNAs (ncRNA) have an essential role in the complex landscape of human genetic regulatory networks. One area that is poorly explored is the effect of genetic variations on the interaction between ncRNA and their targets. By integrating a significant amount of public data, the present study cataloged the vast landscape of the regulatory effect of microRNAs (miRNA) and long intergenic noncoding RNAs (lincRNA) in the human genome. An expression quantitative trait loci (eQTL) analysis was used to identify genetic variants associated with miRNA and lincRNA and whose genotypes affect gene expression. Association networks were built for eQTL associated to traits of clinical and/or pharmacological relevance.

Microarray expression profile of long non-coding RNAs in human lung adenocarcinoma

BACKGROUND

Long non-coding RNAs (lncRNAs) participate in many biological dynamics and play significant roles in gene regulation. LncRNA expression is altered in many cancers; however, the expressions and functions of lncRNA genes in lung adenocarcinoma (LAD) remain unknown.

METHODS

LncRNA and messenger RNA (mRNA) expression in LAD without lymphatic metastasis versus paired adjacent non-tumor (ANT) lung tissues and LAD with versus without lymphatic metastasis were analyzed using Human LncRNA Arraystar V3.0. The expression levels of four downregulated and four upregulated lncRNAs were verified using quantitative real-time PCR in cells and tissue specimens.

RESULTS

In this study, 949 lncRNAs and 681 mRNAs had differential expression in LAD without lymphatic metastasis compared to ANT lung tissues, while 2740 lncRNAs and 1714 mRNAs were differentially expressed in LAD with lymphatic metastasis compared to LAD without lymphatic metastasis. The expression patterns of selected lncRNAs (LINC00113, AC005009.1, ARHGAP22-IT1, AC009411.1, SRGAP3-AS2, EGFEM1P, FAM66E, and HLA-F-AS1) were consistent with microarray data. Differentially expressed mRNA genes were enriched in crucial Gene Ontology terms and pathways.

CONCLUSION

Our results revealed differentially expressed lncRNAs in LAD, suggesting lncRNAs may be potential indicators for LAD diagnosis and therapy.

Integrated analysis of long non‑coding RNA competing interactions revealed potential biomarkers in cervical cancer: Based on a public database

Cervical cancer (CC) is a common gynecological malignancy in women worldwide. Using an RNA sequencing profile from The Cancer Genome Atlas (TCGA) and the CC patient information, the aim of the present study was to identify potential long non‑coding RNA (lncRNA) biomarkers of CC using bioinformatics analysis and building a competing endogenous RNA (ceRNA) co‑expression network. Results indicated several CC‑specific lncRNAs, which were associated with CC clinical information and selected some of them for validation and evaluated their diagnostic values. Bioinformatics analysis identified 51 CC‑specific lncRNAs (fold‑change >2 and P<0.05), and 42 of these were included in ceRNA network consisting of lncRNA‑miRNA‑mRNA interactions. Further analyses revealed that differential expression levels of 19 lncRNAs were significantly associated with different clinical features (P<0.05). A total of 11 key lncRNAs in the ceRNA network for reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis to detect their expression levels in 31 pairs of CC clinical samples. The results indicated that 7 lncRNAs were upregulated and 4 lncRNAs were downregulated in CC patients. The fold‑changes between the RT‑qPCR experiments and the TCGA bioinformatics analyses were the same. Furthermore, the area under the receiver operating characteristic (ROC) curve of four lncRNAs (EMX20S, MEG3, SYS1‑DBNDD2 and MIR9‑3HG) indicated that their combined use may have a significant diagnostic value in CC (P<0.05). To the best of our knowledge, the present study is the first to have identified CC‑specific lncRNAs to construct a ceRNA network and has also provided new insights for further investigation of a lncRNA‑associated ceRNA network in CC. In additon, the verification results suggested that the method of bioinformatics analysis and screening of lncRNAs was accurate and reliable. To conclude, the use of multiple lncRNAs may thus improve diagnostic efficacy in CC. In addition, these specific lncRNAs may serve as new candidate biomarkers for clinical diagnosis, classification and prognosis of CC.

Mechanistic Insights Into the Interaction Between Transcription Factors and Epigenetic Modifications and the Contribution to the Development of Obesity

Objective: The development of obesity is inseparable from genetic and epigenetic factors, and transcription factors (TFs) play an essential role in these two mechanisms. This review analyzes the interaction of TFs with epigenetic modifications and the epigenetic mechanisms underlying peroxisome proliferator-activated receptor (PPAR)γ, an important transcription factor, in the development of obesity. Methods: We describe the relationship between TFs and different epigenetic modifications and illustrate the several mechanisms described. Next, we summarize the epigenetic mechanisms of PPARs, an important class of transcription factors involved in obesity, that induce obesity with different triggering factors. Finally, we discuss the mechanisms of epigenetic modification of PPAR-related ligands in lipid metabolism and propose future avenues of research. Results: TFs participate in epigenetic modifications in different forms, causing changes in gene expression. The interactions between the different epigenetic modifications and PPARs are important biological developments that affect fat tissue differentiation, lipogenesis, and lipid metabolism, thereby inducing or inhibiting the development of obesity. We then highlight the need for more research to understand the role of epigenetic modifications and PPARs. Conclusions: Epigenetic mechanisms involved in the regulation of PPARs may be excellent therapeutic targets for obesity treatment. However, there is a need for a deeper understanding of how PPARs and other obesity-related transcription factors interact with epigenetic modifications.