A novel long noncoding RNA linc00460 up-regulated by CBP/P300 promotes carcinogenesis in esophageal squamous cell carcinoma

Mutual interaction of lncRNAs and epigenetics: focusing on cancer

Long noncoding RNAs are characterized as noncoding transcripts longer than 200 nucleotides in response to a variety of functions within the cells. They are involved in almost all cellular mechanisms so as epigenetics. Given that epigenetics is an important phenomenon, which participates in the biology of complex diseases, many valuable studies have been performed to demonstrate the control status of lncRNAs and epigenetics. DNA methylation and histone modifications as epigenetic mechanisms can regulate the expression of lncRNAs by affecting their coding genes. Reciprocally, the three-dimensional structure of lncRNAs could mechanistically control the activity of epigenetic-related enzymes. Dysregulation in the mutual interaction between epigenetics and lncRNAs is one of the hallmarks of cancer. These mechanisms are either directly or indirectly involved in various cancer properties such as proliferation, apoptosis, invasion, and metastasis. For instance, lncRNA HOTAIR plays a role in regulating the expression of many genes by interacting with epigenetic factors such as DNA methyltransferases and EZH2, and thus plays a role in the initiation and progression of various cancers. Conversely, the expression of this lncRNA is also controlled by epigenetic factors. Therefore, focusing on this reciprocated interaction can apply to cancer management and the identification of prognostic, diagnostic, and druggable targets. In the current review, we discuss the reciprocal relationship between lncRNAs and epigenetic mechanisms to promote or prevent cancer progression and find new potent biomarkers and targets for cancer diagnosis and therapy.

Regulatory Roles of Noncoding RNAs in the Progression of Gastrointestinal Cancers and Health Disparities

Annually, more than a million individuals are diagnosed with gastrointestinal (GI) cancers worldwide. With the advancements in radio- and chemotherapy and surgery, the survival rates for GI cancer patients have improved in recent years. However, the prognosis for advanced-stage GI cancers remains poor. Site-specific GI cancers share a few common risk factors; however, they are largely distinct in their etiologies and descriptive epidemiologic profiles. A large number of mutations or copy number changes associated with carcinogenesis are commonly found in noncoding DNA regions, which transcribe several noncoding RNAs (ncRNAs) that are implicated to regulate cancer initiation, metastasis, and drug resistance. In this review, we summarize the regulatory functions of ncRNAs in GI cancer development, progression, chemoresistance, and health disparities. We also highlight the potential roles of ncRNAs as therapeutic targets and biomarkers, mainly focusing on their ethnicity-/race-specific prognostic value, and discuss the prospects of genome-wide association studies (GWAS) to investigate the contribution of ncRNAs in GI tumorigenesis.

Oncogenic roles of the lncRNA LINC00460 in human cancers

Long noncoding RNAs (lncRNAs) represent an important group of endogenous RNAs with limit protein-encoding capability, with a length of more than 200 nucleotides. Emerging evidence have demonstrated that lncRNAs are greatly involved in multiple cancers by playing critical roles in tumor initiation and progression. Long intergenic non-protein coding RNA 460 (LINC00460), a novel cancer-related lncRNA, exhibits abnormal expression and oncogenic function in multiple cancers, and positively correlates with poor clinical characteristics of cancer patients. LINC00460 has also been shown to be a promising biomarker for diagnosis as well as prognostic evaluation in cancer patients. In this review, we briefly summarized recent knowledge on the expression, functional roles, molecular mechanisms, and diagnostic and prognostic values of LINC00460 in human malignancies.

Unraveling diverse roles of noncoding RNAs in various human papillomavirus negative cancers

Human papillomavirus (HPV)-negative tumors distinguish from cancers associated with HPV infection. Due to its high rate of lymph node metastasis and difficulty in inchoate discover and diagnosis, the treatment efficacy of HPV-negative cancers is unsatisfactory. Epidemiological evidence suggests that HPV-negative tumor patients have a poor prognosis, and the mortality is higher than that of cancer patients caused by HPV infection. Evidence has demonstrated that noncoding RNAs (ncRNAs) play a crucial role in regulation of physiological and developmental processes. Therefore, dysregulated ncRNAs are involved in the occurrence of diversified diseases, including cancer. In cumulative studies, ncRNAs are concerned with pathogenetic mechanisms of HPV-negative tumors via regulating gene expression and signal transduction. It is important to decipher the functions of ncRNAs in HPV-negative cancers and identify the potential biomarkers, which will bring new treatment strategies for improving outcome of cancer therapy. In this review, we demonstrated the effects of ncRNAs via regulating the development and progression of HPV- negative tumors by directly or indirectly acting on target molecules, which provide a basis for future tumor targeted therapy by targeting ncRNAs for HPV-negative cancers.

A Pleiotropic Role of Long Non-Coding RNAs in the Modulation of Wnt/β-Catenin and PI3K/Akt/mTOR Signaling Pathways in Esophageal Squamous Cell Carcinoma: Implication in Chemotherapeutic Drug Response

Despite the availability of modern techniques for the treatment of esophageal squamous cell carcinoma (ESCC), tumor recurrence and metastasis are significant challenges in clinical management. Thus, ESCC possesses a poor prognosis and low five-year overall survival rate. Notably, the origin and recurrence of the cancer phenotype are under the control of complex cancer-related signaling pathways. In this review, we provide comprehensive knowledge about long non-coding RNAs (lncRNAs) related to Wnt/β-catenin and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway in ESCC and its implications in hindering the efficacy of chemotherapeutic drugs. We observed that a pool of lncRNAs, such as HERES, TUG1, and UCA1, associated with ESCC, directly or indirectly targets various molecules of the Wnt/β-catenin pathway and facilitates the manifestation of multiple cancer phenotypes, including proliferation, metastasis, relapse, and resistance to anticancer treatment. Additionally, several lncRNAs, such as HCP5 and PTCSC1, modulate PI3K/Akt/mTOR pathways during the ESCC pathogenesis. Furthermore, a few lncRNAs, such as AFAP1-AS1 and LINC01014, block the efficiency of chemotherapeutic drugs, including cisplatin, 5-fluorouracil, paclitaxel, and gefitinib, used for ESCC treatment. Therefore, this review may help in designing a better therapeutic strategy for ESCC patients.

LncRNA LINC00460: Function and mechanism in human cancer

Long non-coding RNAs (LncRNAs), which are more than 200 nucleotides in length and with limited protein-coding potential, play vital roles in the pathogenesis, tumorigenesis, and angiogenesis of cancers. Aberrant expression of lncRNAs has been detected in various carcinomas and may be correlated with oncogenesis by affecting related genes expression. Recently, an increasing number of studies have reported on long intergenic non-protein coding RNA 460 (LINC00460) in human tumor fields. LINC00460 is upregulated in diverse cancer tissues and cells. The upregulated expression level of LINC00460 is correlated with larger tumor size, tumor node metastasis (TNM) stage, lymph node metastasis, and shorter overall survival. The regulatory mechanism of LINC00460 was complex and diverse. LINC00460 could act as a competitive endogenous RNA (ceRNA), directly bind with proteins or regulate multiple pathways, which affected tumor progression. Moreover, LINC00460 was also identified to increase drug resistance, and therefore, weaken the effectiveness of tumor treatment. It has become increasingly important to investigate the roles of LINC00460 in various cancers by different mechanisms. Therefore, a more comprehensive understanding of LINC00460 is crucial to expound on the cellular function and molecular mechanism of human cancers. In this review, we refer to studies concerning LINC00460 and provide the basis for the evaluation of LINC00460 as a predicted biomarker or potential therapeutic target in malignancies, and also provide ideas for the future research of lncRNAs similar to LINC00460.

Identification of a Somatic Mutation-Derived Long Non-Coding RNA Signatures of Genomic Instability in Renal Cell Carcinoma

Background

Renal cell carcinoma (RCC) is a malignant tumor with high morbidity and mortality. It is characterized by a large number of somatic mutations and genomic instability. Long non-coding RNAs (lncRNAs) are widely involved in the expression of genomic instability in renal cell carcinoma. But no studies have identified the genome instability-related lncRNAs (GInLncRNAs) and their clinical significances in RCC.

Methods

Clinical data, gene expression data and mutation data of 943 RCC patients were downloaded from The Cancer Genome Atlas (TCGA) database. Based on the mutation data and lncRNA expression data, GInLncRNAs were screened out. Co-expression analysis, Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted to explore their potential functions and related signaling pathways. A prognosis model was further constructed based on genome instability-related lncRNAs signature (GInLncSig). And the efficiency of the model was verified by receiver operating characteristic (ROC) curve. The relationships between the model and clinical information, prognosis, mutation number and gene expression were analyzed using correlation prognostic analysis. Finally, the prognostic model was verified in clinical stratification according to TCGA dataset.

Results

A total of 45 GInLncRNAs were screened out. Functional analysis showed that the functional genes of these GInLncRNAs were mainly enriched in chromosome and nucleoplasmic components, DNA binding in molecular function, transcription and complex anabolism in biological processes. Univariate and Multivariate Cox analyses further screened out 11 GInLncSig to construct a prognostic model (AL031123.1, AC114803.1, AC103563.7, AL031710.1, LINC00460, AC156455.1, AC015977.2, 'PRDM16-dt', AL139351.1, AL035661.1 and LINC01606), and the coefficient of each GInLncSig in the model was calculated. The area under the curve (AUC) value of the ROC curve was 0.770. Independent analysis of the model showed that the GInLncSig model was significantly correlated with the RCC patients' overall survival. Furthermore, the GInLncSig model still had prognostic value in different subgroups of RCC patients.

Conclusion

Our study preliminarily explored the relationship between genomic instability, lncRNA and clinical characteristics of RCC patients, and constructed a GInLncSig model consisted of 11 GInLncSig to predict the prognosis of patients with RCC. At the same time, our study provided theoretical support for the exploration of the formation and development of RCC.

Significance of LINC00460 in the progression and prognosis in digestive tract tumors

The long intergic non-protein coding RNA 460 (LINC00460) is abnormally highly expressed in gastrointestinal tumors and plays an important role in promoting tumor formation and development. LINC00460 is mainly distributed in cytoplasm and has many abnormal gene variants of single nucleotide polymorphism in tumors. LINC00460 can promote the proliferation, metastasis, angiogenesis, radiotherapy and chemotherapy resistance, inhibit the apoptosis of tumor cells, and further promote the malignant progression of tumors via involving in chromatin state maintenance, methylation modification, endogenous competition and transcriptional regulation. It may serve as a valuable tumor marker and therapeutic target.

Genome instability-related long non-coding RNA in clear renal cell carcinoma determined using computational biology

Background

There is evidence that long non-coding RNA (lncRNA) is related to genetic stability. However, the complex biological functions of these lncRNAs are unclear.

Method

TCGA - KIRC lncRNAs expression matrix and somatic mutation information data were obtained from TCGA database. “GSVA” package was applied to evaluate the genomic related pathway in each samples. GO and KEGG analysis were performed to show the biological function of lncRNAs-mRNAs. “Survival” package was applied to determine the prognostic significance of lncRNAs. Multivariate Cox proportional hazard regression analysis was applied to conduct lncRNA prognosis model.

Results

In the present study, we applied computational biology to identify genome-related long noncoding RNA and identified 26 novel genomic instability-associated lncRNAs in clear cell renal cell carcinoma. We identified a genome instability-derived six lncRNA-based gene signature that significantly divided clear renal cell samples into high- and low-risk groups. We validated it in test cohorts. To further elucidate the role of the six lncRNAs in the model’s genome stability, we performed a gene set variation analysis (GSVA) on the matrix. We performed Pearson correlation analysis between the GSVA scores of genomic stability-related pathways and lncRNA. It was determined that LINC00460 and LINC01234 could be used as critical factors in this study. They may influence the genome stability of clear cell carcinoma by participating in mediating critical targets in the base excision repair pathway, the DNA replication pathway, homologous recombination, mismatch repair pathway, and the P53 signaling pathway.

Conclusion subsections

These data suggest that LINC00460 and LINC01234 are crucial for the stability of the clear cell renal cell carcinoma genome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08356-9.

Long Intergenic Non-Coding RNAs in HNSCC: From "Junk DNA" to Important Prognostic Factor

Head and neck squamous cell carcinoma is one of the most common and fatal cancers worldwide. Even a multimodal approach consisting of standard chemo- and radiotherapy along with surgical resection is only effective in approximately 50% of the cases. The rest of the patients develop a relapse of the disease and acquire resistance to treatment. Especially this group of individuals needs novel, personalized, targeted therapy. The first step to discovering such solutions is to investigate the tumor microenvironment, thus understanding the role and mechanism of the function of coding and non-coding sequences of the human genome. In recent years, RNA molecules gained great interest when the complex character of their impact on our biology allowed them to come out of the shadows of the "junk DNA" label. Furthermore, long non-coding RNAs (lncRNA), specifically the intergenic subgroup (lincRNA), are one of the most aberrantly expressed in several malignancies, which makes them particularly promising future diagnostic biomarkers and therapeutic targets. This review contains characteristics of known and validated lincRNAs in HNSCC, such as XIST, MALAT, HOTAIR, HOTTIP, lincRNA-p21, LINC02487, LINC02195, LINC00668, LINC00519, LINC00511, LINC00460, LINC00312, and LINC00052, with a description of their prognostic abilities. Even though much work remains to be done, lincRNAs are important factors in cancer biology that will become valuable biomarkers of tumor stage, outcome prognosis, and contribution to personalized medicine.

Development and Interpretation of a Genomic Instability Derived lncRNAs Based Risk Signature as a Predictor of Prognosis for Clear Cell Renal Cell Carcinoma Patients

Background

Clear cell renal cell carcinoma (ccRCC) is a kind of frequently diagnosed cancer, leading to high death rate in patients. Genomic instability (GI) is regarded as playing indispensable roles in tumorigenesis and impacting the prognosis of patients. The aberrant regulation of long non-coding RNAs (lncRNAs) is a main cause of GI. We combined the somatic mutation profiles and expression profiles to identify GI derived lncRNAs (GID-lncRNAs) in ccRCC and developed a GID-lncRNAs based risk signature for prognosis prediction and medication guidance.

Methods

We decided cases with top 25% cumulative number of somatic mutations as genomically unstable (GU) group and last 25% as genomically stable (GS) group, and identified differentially expressed lncRNAs (GID-lncRNAs) between two groups. Then we developed the risk signature with all overall survival related GID-lncRNAs with least absolute shrinkage and selection operator (LASSO) Cox regression. The functions of the GID-lncRNAs were partly interpreted by enrichment analysis. We finally validated the effectiveness of the risk signature in prognosis prediction and medication guidance.

Results

We developed a seven-lncRNAs (LINC00460, AL139351.1, AC156455.1, AL035446.1, LINC02471, AC022509.2, and LINC01606) risk signature and divided all samples into high-risk and low-risk groups. Patients in high-risk group were in more severe clinicopathologic status (higher tumor grade, pathological stage, T stage, and more metastasis) and were deemed to have less survival time and lower survival rate. The efficacy of prognosis prediction was validated by receiver operating characteristic analysis. Enrichment analysis revealed that the lncRNAs in the risk signature mainly participate in regulation of cell cycle, DNA replication, material metabolism, and other vital biological processes in the tumorigenesis of ccRCC. Moreover, the risk signature could help assess the possibility of response to precise treatments.

Conclusion

Our study combined the somatic mutation profiles and the expression profiles of ccRCC for the first time and developed a GID-lncRNAs based risk signature for prognosis predicting and therapeutic scheme deciding. We validated the efficacy of the risk signature and partly interpreted the roles of the seven lncRNAs composing the risk signature in ccRCC. Our study provides novel insights into the roles of genomic instability derived lncRNAs in ccRCC.

Long non‑coding RNA LINC00460 serves as a potential biomarker and oncogene via regulation of the miR‑320b/PBX3 axis in acute myeloid leukemia

Long non-coding RNA 00460 (LINC00460) has been reported to be involved in the tumorigenesis of various cancer types. However, the function of LINC00460 in acute myeloid leukemia (AML) remains elusive. Therefore, the present study aimed to investigate the role of LINC00460 in AML. The expression of LINC00460 in the serum of 80 diagnosed patients with AML and 67 healthy controls was measured via reverse transcription-quantitative polymerase chain reaction, and the results were compared with clinical features and patient outcomes. The expression of LINC00460 in 45 patients with cytogenetically normal-AML (CN-AML) was also assayed. Receiver operating characteristic (ROC) curves were generated to evaluate the sensitivity and specificity of serum LINC00460. In addition, the effects of LINC00460 on the viability, cell cycle distribution and apoptosis of AML cells were investigated. Bioinformatics tools were used to identify the possible mechanisms of how LINC00460 affects AML cells. It was found that the expression of LINC00460 was significantly upregulated in the serum of patients with AML and those with CN-AML. Higher expression of serum LINC00460 was positively associated with French-American-British classification and cytogenetics. Furthermore, ROC curve analyses demonstrated that serum LINC00460 could differentiate patients with AML from healthy individuals with an area under the curve of 0.8488 (95% CI, 0.7697–0.9279). The serum LINC00460 expression was also significantly decreased when the patients achieved complete remission. Kaplan-Meier analysis indicated that patients with high serum LINC00460 expression had a shorter overall survival time compared with the low serum LINC00460 expression group. Knockdown of LINC00460 inhibited viability, while inducing cell cycle arrest and apoptosis in AML cells. LINC00460 was also a decoy of microRNA (miR)-320b, which can further inhibit the expression of PBX homeobox 3 (PBX3). Collectively, the results suggested that LINC00460 may be applied as a potential diagnostic and prognostic biomarker for patients with AML. It was identified that LINC00460 may exert its effects, at least partly, via the miR-320b/PBX3 axis in AML.

LINC00460 Is a Dual Biomarker That Acts as a Predictor for Increased Prognosis in Basal-Like Breast Cancer and Potentially Regulates Immunogenic and Differentiation-Related Genes

Breast cancer (BRCA) is a serious public health problem, as it is the most frequent malignant tumor in women worldwide. BRCA is a molecularly heterogeneous disease, particularly at gene expression (mRNAs) level. Recent evidence shows that coding RNAs represent only 34% of the total transcriptome in a human cell. The rest of the 66% of RNAs are non−coding, so we might be missing relevant biological, clinical or regulatory information. In this report, we identified two novel tumor types from TCGA with LINC00460 deregulation. We used survival analysis to demonstrate that LINC00460 expression is a marker for poor overall (OS), relapse-free (RFS) and distant metastasis-free survival (DMFS) in basal-like BRCA patients. LINC00460 expression is a potential marker for aggressive phenotypes in distinct tumors, including HPV-negative HNSC, stage IV KIRC, locally advanced lung cancer and basal-like BRCA. We show that the LINC00460 prognostic expression effect is tissue-specific, since its upregulation can predict poor OS in some tumors, but also predicts an improved clinical course in BRCA patients. We found that the LINC00460 expression is significantly enriched in the Basal-like 2 (BL2) TNBC subtype and potentially regulates the WNT differentiation pathway. LINC00460 can also modulate a plethora of immunogenic related genes in BRCA, such as SFRP5, FOSL1, IFNK, CSF2, DUSP7 and IL1A and interacts with miR-103-a-1, in-silico, which, in turn, can no longer target WNT7A. Finally, LINC00460:WNT7A ratio constitutes a composite marker for decreased OS and DMFS in Basal-like BRCA, and can predict anthracycline therapy response in ER-BRCA patients. This evidence confirms that LINC00460 is a master regulator in BRCA molecular circuits and influences clinical outcome.

Bioinformatics-based analysis of the lncRNA-miRNA-mRNA and TF regulatory networks reveals functional genes in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a 5-year survival rate unsatisfied malignancies. The study aimed to identify the novel diagnostic and prognostic targets for ESCC. Expression profiling (GSE89102, GSE97051, and GSE59973) data were downloaded from the GEO database. Then, differentially expressed (DE) lncRNAs, DEmiRNAs, and genes (DEGs) with P-values < 0.05, and |log₂FC| ≥ 2, were identified using GEO2R. Functional enrichment analysis of miRNA-related mRNAs and lncRNA co-expressed mRNA was performed. LncRNA–miRNA–mRNA, protein–protein interaction of miRNA-related mRNAs and DEGs, co-expression, and transcription factors-hub genes network were constructed. The transcriptional data, the diagnostic and prognostic value of hub genes were estimated with ONCOMINE, receiver operating characteristic (ROC) analyses, and Kaplan–Meier plotter, respectively. Also, the expressions of hub genes were assessed through qPCR and Western blot assays. The CDK1, VEGFA, PRDM10, RUNX1, CDK6, HSP90AA1, MYC, EGR1, and SOX2 used as hub genes. And among them, PRDM10, RUNX1, and CDK6 predicted worse overall survival (OS) in ESCC patients. Our results showed that the hub genes were significantly up-regulated in ESCA primary tumor tissues and cell lines, and exhibited excellent diagnostic efficiency. These results suggest that the hub genes may server as potential targets for the diagnosis and treatment of ESCC.

Multifaceted Roles of Long Non-coding RNAs in Head and Neck Cancer

The majority of RNA transcripts are non-coding RNA (ncRNA) transcripts with lengths exceeding 200 nucleotides that are not translated into protein. Unlike microRNAs (miRNAs), long ncRNAs (lncRNAs) are not confined to a single mechanism of action but have a large and diverse role in biological processes as they can function as transcription regulators, decoys, scaffolds, and enhancer RNAs. Currently, many lncRNA molecules are under investigation for their role in tumorigenesis, metastasis, and prognosis in different types of cancer. This review not only summarizes the characteristics and functions of lncRNAs but also discusses the therapeutic implications and applications of lncRNAs with roles associated with head and neck cancer. Our aim is to pinpoint the potential way to perturb specific lncRNAs for future therapeutic use.

Involvement of long non-coding RNAs in the progression of esophageal cancer

Esophageal cancer (EC) is one of the most common malignant tumors of the digestive system with high incidence and mortality rate worldwide. Therefore, exploring the pathogenesis of EC and searching for new targeted therapies are the current research hotspot for EC treatment. Long non‐coding RNAs (lncRNAs) are endogenous RNAs with more than 200 nucleotides, but without protein‐coding function. In recent years, lncRNAs have gradually become the focuses in the field of non‐coding RNA. Some lncRNAs have been proved to be closely related to the pathogenesis of EC. Many lncRNAs are abnormally expressed in EC and participate in many biological processes including cell proliferation, apoptosis, and metastasis by inhibiting or promoting target gene expression. LncRNAs can also regulate the progression of EC through epithelial‐mesenchymal transformation (EMT), which is closely related to the occurrence, development, and prognosis of EC. In this article, we review and discuss the involvement of lncRNAs in the progression of EC.

Long Noncoding RNA FAM225A Promotes Esophageal Squamous Cell Carcinoma Development and Progression via Sponging MicroRNA-197-5p and Upregulating NONO

Esophageal squamous cell carcinoma (ESCC) is the major subclass of esophageal cancer and one of the most life-threatening malignancies with high morbidity and mortality. Long noncoding RNAs (lncRNAs) participate in tumorigenesis and metastasis of various tumors. Here, we investigated the function of a newly identified lncRNA FAM225A in ESCC. LncRNA FAM225A expression was significantly higher in ESCC and predicted poor prognosis of ESCC patients. We confirmed that upregulation of FAM225A in ESCC and overexpression of FAM225A was associated with poor outcome in ESCC patients using TCGA ESCC cohort. Knockdown of FAM225A significantly inhibited cell growth, migration and invasion of ESCC cells in vitro and inhibited ESCC xenograft development in vivo. Mechanistically, we demonstrated that lncRNA FAM225A functioned as a competing endogenous RNA (ceRNA) via sponging miR-197-5p. LncRNA FAM225A exerted its regulatory function on ESCC proliferation and metastasis via modulating expression of miR-197-5p. MiR-197-5p overexpression antagonized the function of FAM225A, with decreased cell growth and invasion. Moreover, we identified that RNA binding protein NONO was a direct target of miR-197-5p and miR-197-5p negatively regulated NONO expression and TGF-β signaling in ESCC cells. In summary, our findings suggest that lncRNA FAM225A promotes ESCC development and progression via sponging miR-197-5p and upregulating NONO expression. These results suggest that lncRNA FAM225A could be explored as a new therapy target in ESCC treatment.

Comprehensive analysis of prognostic biomarkers in lung adenocarcinoma based on aberrant lncRNA-miRNA-mRNA networks and Cox regression models

Lung adenocarcinoma (LUAD) is the leading cause of cancer-related death worldwide, and its underlying mechanism remains unclear. Accumulating evidence has highlighted that long non-coding RNA (lncRNA) acts as competitive endogenous RNA (ceRNA) and plays an important role in the occurrence and development of LUAD. Here, we comprehensively analyzed and provided an overview of the lncRNAs, miRNAs, and mRNAs associated with LUAD from The Cancer Genome Atlas (TCGA) database. Then, differentially expressed lncRNAs (DElncRNA), miRNAs (DEmiRNA), and mRNAs (DEmRNA) were used to construct a lncRNA–miRNA–mRNA regulatory network according to interaction information from miRcode, TargetScan, miRTarBase, and miRDB. Finally, the RNAs of the network were analyzed for survival and submitted for Cox regression analysis to construct prognostic indicators. A total of 1123 DElncRNAs, 95 DEmiRNAs, and 2296 DEmRNAs were identified (|log₂FoldChange| (FC) > 2 and false discovery rate (FDR) or adjusted P value < 0.01). The ceRNA network was established based on this and included 102 lncRNAs, 19 miRNAs, and 33 mRNAs. The DEmRNAs in the ceRNA network were found to be enriched in various cancer-related biological processes and pathways. We detected 22 lncRNAs, 12 mRNAs, and 1 miRNA in the ceRNA network that were significantly associated with the overall survival of patients with LUAD (P < 0.05). We established three prognostic prediction models and calculated the area under the 1,3,5-year curve (AUC) values of lncRNA, mRNA, and miRNA, respectively. Among them, the prognostic index (PI) of lncRNA showed good predictive ability which was 0.737, 0.702 and 0.671 respectively, and eight lncRNAs can be used as candidate prognostic biomarkers for LUAD. In conclusion, our study provides a new perspective on the prognosis and diagnosis of LUAD on a genome-wide basis, and develops independent prognostic biomarkers for LUAD.

A novel long noncoding RNA, LOC440173, promotes the progression of esophageal squamous cell carcinoma by modulating the miR-30d-5p/HDAC9 axis and the epithelial-mesenchymal transition

Countless evidence suggests that long noncoding RNAs (lncRNAs) are involved in human malignant cancers, including esophageal squamous cell carcinoma (ESCC), although their exact function remains unclear. In the present study, we aimed to investigate the roles and molecular mechanisms of the lncRNA LOC440173 in ESCC progression. Microarray analysis and quantitative real-time polymerase chain reaction were conducted to measure the expression levels of LOC440173 and miR-30d-5p. The biological function of this lncRNA was investigated using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, clone formation, and transwell assays, as well as flow cytometry and Western blot analysis. The function of LOC440173 was validated in vivo using tumor xenografts. The regulatory network of LOC440173/miR-30d-5p/HDAC9 was established using bioinformatic analysis and verified with dual-luciferase reporter assays, RNA immunoprecipitation assay, and rescue experiments. The expression level of LOC440173 was significantly increased in ESCC tissues and esophageal carcinoma cells. High LOC440173 expression was correlated with histological grade, tumor invasion depth, lymph node metastasis, and TNM stage. Overexpression of LOC440173 promoted esophageal cancer cell proliferation, migration, and invasion, as well as the epithelial-mesenchymal transition (EMT) process in vitro, and facilitated tumor growth in vivo. MicroRNA-30d-5p (miR-30d-5p) was downregulated in ESCC tissues and acted as a direct binding target of LOC440173 during the regulation of HDAC9 expression in esophageal carcinoma cells. In conclusion, LOC440173 exerts a promotive role in ESCC tumorigenesis by targeting the miR-30d-5p/HDAC9 axis and regulating the EMT process. LOC440173 might be a new therapeutic target for the treatment of ESCC.

LINC00460-miR-149-5p/miR-150-5p-Mutant p53 Feedback Loop Promotes Oxaliplatin Resistance in Colorectal Cancer

Oxaliplatin resistance is a major challenge in the clinical treatment for advanced colorectal cancer (CRC). Long non-coding RNAs (lncRNAs) are involved in tumorigenesis and progression as critical regulators, while their potential roles in chemoresistance are poorly understood. In this study, we report that the LINC00460-miR-149-5p/miR-150-5p-mutant p53 feedback loop is responsible for oxaliplatin resistance in CRC. First, LINC00460 was found to exhibit higher expression in oxaliplatin-resistant CRC (CRC/OxR) cells compared with parental oxaliplatin-sensitive ones, and this expression pattern depends on mutant p53 (SW480/OxR), not wild-type p53 (HCT116/OxR). Oxaliplatin-induced LINC00460 in SW480/OxR cells was mainly located in the cytoplasm and was associated with AGO2 protein. LINC00460 functions as a competing endogenous RNA (ceRNA) to promote oxaliplatin resistance through sequestering miR-149-5p/miR-150-5p and upregulating the expression of the microRNA (miRNA) target p53. Knockdown of LINC00460 sensitized SW480/OxR cells to oxaliplatin by modulating p53 in vitro and in vivo. In turn, mutant p53 positively regulated the expression of LINC00460, thus forming a feedback loop. Clinical data showed that LINC00460 was upregulated in CRC tissues compared with paired normal tissues and was significantly correlated with clinical stage and node (N) status. Our findings uncover a mechanism for the LINC00460-miR-149-5p/miR-150-5p-mutant p53 feedback loop in oxaliplatin resistance of CRC, and they provide potential therapeutic targets for tumor chemoresistance.

LINC00460 Enhances Bladder Carcinoma Cell Proliferation and Migration by Modulating miR-612/FOXK1 Axis

INTRODUCTION

LincRNA (long intergenic noncoding RNA) has been indicated as a mediator in tumorigenesis of bladder carcinoma. This study was performed to evaluate the role of LINC00460 in bladder carcinoma progression.

METHODS

Expression levels of LINC00460 in bladder carcinoma tissues and cell lines were analyzed via qRT-PCR. MTT, EdU (5-ethynyl-2'-deoxyuridine) staining, and colony formation assays were utilized to evaluate cell viability and proliferation. The wound healing assay was performed to evaluate bladder cancer cell migration, and the transwell assay was used to evaluate cell invasion. The microRNA (miRNA) target of LINC00460 and the corresponding target gene were validated via the dual luciferase activity assay. The tumorigenic function of LINC00460 was determined via establishment of a xenotransplanted tumor model.

RESULTS

LINC00460 was elevated in bladder carcinoma tissues and cell lines. Elevated LINC00460 was associated with shorter overall survival of bladder carcinoma patients. Overexpression of LINC00460 promoted cell viability, proliferation, invasion, and migration, while silencing of LINC00460 indicated the opposite effect on bladder carcinoma progression. LINC00460 could directly bind to miR-612 and inhibit miR-612 expression. Moreover, LINC00460 expression was negatively correlated with miR-612 in patients with bladder carcinoma. FOXK1 (Forkhead Box K1) was identified as the target of miR-612 and upregulated in patients with bladder carcinoma. Overexpression of FOXK1 attenuated interference of LINC00460-inhibited bladder carcinoma progression. Knockdown of LINC00460 suppressed in vivo bladder carcinoma growth.

CONCLUSIONS

LINC00460 promoted bladder carcinoma progression via sponging miR-612 to facilitate FOXK1 expression, suggesting that LINC00460 might have the potential of being explored as a therapeutic target for treatment of bladder carcinoma.

Lnc-MCEI mediated the chemosensitivity of esophageal squamous cell carcinoma via miR-6759-5p to competitively regulate IGF2

Large amounts of long non-coding RNAs (lncRNAs) have been annotated whereas most of them have not been functionally characterized. Here we identified lncRNA ENST00000441932 as an oncogenic lncRNA in esophageal squamous cell carcinoma (ESCC) and named lnc-MCEI (lncRNA mediated the chemosensitivity of ESCC by regulating IGF2). What's more, the effect of lnc-MCEI on the chemosensitivity of ESCC was further evaluated. Bioinformatics analysis demonstrated that lnc-MCEI was involved in the tumorigenesis of ESCC and lnc-MCEI levels were significantly increased in ESCC cells and tissues. Additionally, lnc-MCEI knockdown retarded cell proliferation, colony formation of ESCC cells, but induced cell apoptosis. Moreover, lnc-MCEI knockdown significantly improved the chemosensitivity of ESCC to cisplatin (DDP) both in vivo and in vitro. Further mechanisms disclosed that lnc-MCEI functioned as a competing endogenous RNA (ceRNA) via sponging miR-6759-5p and IGF2 was a target of miR-6759-5p. Meanwhile, we found that IGF2 suppressed chemosensitivity of ESCC cells via PI3K/AKT pathway. These data suggested that lnc-MCEI was an oncogenic lncRNA and lnc-MCEI knockdown enhanced chemosensitivity of ESCC cells to cisplatin by targeting miR-6759-5p /IGF2/PI3K/AKT axis.

Long Noncoding RNA LINC00460 Facilitates Colorectal Cancer Progression by Negatively Regulating miR-613

Background

Long-noncoding RNAs (lncRNAs) could exert a crucial effect on the development of human cancers, including CRC. However, the biological function and underlying mechanism of LINCRNA00460 in the development of CRC still need deeper exploration.

Materials and Methods

The expression of LINC00460 in CRC tissues and cell lines was assessed by qRT-PCR. Cell proliferation, migration, and invasion were measured by the respective cell counting Kit-8 (CCK-8), wound healing assay and transwell invasion assay. Cell apoptosis and caspase-3 activity were detected by flow cytometry and caspase-3 activity assay. The relationship between LINC00460 and miR-613 expression was explored by Dual-luciferase reporter assay. Protein expression was measured by Western blotting. In vivo tumour growth was evaluated using a xenograft model of nude mice.

Results

LINC00460 was markedly up-regulated in CRC tissues and cell lines compared to their corresponding controls, which was closely correlated with clinical stage, TNM (T) classification, nodal (N) classification, metastasis (M) classification, liver metastasis and pathological differentiation, and survival rate of CRC patients. Functionally, LINC00460 knockdown decreased the proliferative, migrative and invasive abilities, and enhanced apoptosis rates and caspase-3 activity in HT29 and LOVO cells. Mechanistic studies indicated that miR-613 was targeted by LINC00460, and SphK1 was targeted and inversely regulated by miR-613 in HT29 and LOVO cells. In vivo studies, LINC00460 knockdown attenuated tumour growth. MiR-613 downregulation and SphK1 upregulation in the CRC tissues, and LINC00460 expression levels were inversely correlated with miR-613 expression and positively correlated with the SphK1 mRNA expression. Overall, LINC00460 modulated cell proliferation, migration, invasion and sphingosine kinase 1 (SphK1) expression in HT29 and LOVO cells, at least in most part, by regulating miR‐613.

Conclusion

LINC00460 functions as a competing endogenous RNA to regulate SphK1 expression by sponging miR‐613 in CRC and provides a valuable therapeutic strategy for CRC patients.

Long intergenic non-coding RNA 00337 confers progression of esophageal cancer by mediating microrna-145-dependent fscn1

Long non-coding RNAs (lncRNAs) have been highlighted as prominent genetic modulators involved in multiple important biological processes of cancer cells, especially in esophageal cancer (EC). We tried to elucidate the potential role of LINC00337 in the progression of EC. Based on TCGA database analysis and Reverse transcription quantitative polymerase chain reaction determination, high expression of LINC00337 and FSCN1 was detected, while miR-145 exhibited a low expression in EC. LINC00337 was identified to bind to miR-145 to impair the miR-145-dependent FSCN1 inhibition. The underlying regulatory mechanisms were evaluated by transfection with LINC00337 overexpression plasmid, siRNA against LINC00337, miR-145 mimic, or anta-miR-145. Downregulation of LINC00337 results in increased Bax level, decreased FSCN1, Bcl-2, VEGF, and p53 levels, in addition to diminished cell proliferation, migration, invasion and tumor growth, with accelerated cell apoptosis by upregulating miR-145. Taken together, the findings obtained provided evidence suggesting that LINC00337 acts as a tumor promoter in EC, providing insight and advancements for EC treatment.

Long noncoding RNA LINC00460 conduces to tumor growth and metastasis of hepatocellular carcinoma through miR-342-3p-dependent AGR2 up-regulation

Hepatocellular carcinoma (HCC) is the fifth most common malignant tumor in the world. It ranks third among cancer-induced deaths worldwide and has the characteristics of high metastasis and high recurrence rate. Long non-coding RNA (LncRNA) LINC00460 is significantly up-regulated in multiple types of cancers and is closely related to the progression of tumors. However, effects of LINC00460 and corresponding regulatory path in HCC are still poorly investigated.

In our study, we found that expression of LINC00460 was up-regulated in HCC tissues and cell lines compared with the control. Then we revealed that knockdown of LINC00460 suppressed cell proliferation and cell mobility and induced cell apoptosis in HCC cells. Further study demonstrated that knockdown of LINC00460 suppressed the progression of HCC by elevating the expression of microRNA (miRNA, miR)-342-3p. Besides that, metastasis marker, Anterior gradient homolog 2 (AGR2) was found to be a target of miR-342-3p and overexpression of AGR2 promoted the progression of HCC. Finally, the in vivo experiments further verified the anti-tumor effects of LINC00460 / miR-342-3p / AGR2 axis in HCC.

The LINC00460 / miR-342-3p / AGR2 axis exerts anti-tumor effect in HCC in vitro and in vivo, consolidating and expanding the research about targeted gene therapy for early diagnosis and treatment of HCC.

LncRNA linc00460 sponges miR-1224-5p to promote esophageal cancer metastatic potential and epithelial-mesenchymal transition

BACKGROUND

Increasing studies highlight the crucial role of long non-coding RNAs (lncRNAs) in carcinogenesis of various human cancer types, including esophageal cancer (ESCA). Long intergenic non-coding RNA 00460 (Linc00460), a novel oncogenic lncRNA, has been reported to accelerate ESCA cell growth. This study aimed to investigate the role and possible regulatory mechanism of linc00460 in ESCA metastasis.

METHODS

Bioinformatics analysis and quantitative real time polymerase chain reaction (qRT-PCR) were used to detect linc00460 expression in ESCA. Wound healing assay, Transwell assay and Western blot were utilized to examine migration, invasion and epithelial-mesenchymal transition (EMT) of ESCA cells. The direct binding effect between linc00460 and microRNA-1224-5p (miR-1224-5p) was evaluated by the dual luciferase reporter assay.

RESULTS

In this study, we discovered that lncRNA linc00460 was obviously over-expressed in ESCA, both in tissues and cell lines. Down-regulation of linc00460 significantly suppressed the metastatic potential (including cell migration and invasion) and EMT of ESCA cells. In addition, miR-1224-5p, a potential tumor suppressor, was negatively correlated with linc00460 in ESCA. Linc00460 and miR-1224-5p could bind directly in ESCA cells. Inhibition of miR-1224-5p partially abrogated the effects of linc00460 decrease on metastatic potential and EMT of ESCA cells.

CONCLUSIONS

Taken together, linc00460 may function as a molecular sponge to adsorb miR-1224-5p, thereby promoting ESCA metastasis and EMT. Our findings suggest that linc00460/miR-1224-5p is a possible clinical target for ESCA.

Long non-coding RNA LINC00460 predicts poor survival and promotes cell viability in pancreatic cancer

Emerging evidence has demonstrated that long non-coding RNAs (lncRNAs) possess great potential as vital biomarkers and powerful therapeutic targets in various diseases. In the present study, differentially expressed transcripts in pancreatic cancer (PC) were identified, and a competing endogenous RNA (ceRNA) network was constructed using The Cancer Genome Atlas database. An independent cohort consisting of 59 patients with PC was used to validate the clinical value of the identified lncRNA. Cell viability and colony formation assays were used to evaluate the biological functions of the lncRNA in PC cells. The present bioinformatic analysis revealed that LINC00460 was upregulated in PC samples with a prognostic significance. In the ceRNA network, it potentially targeted the microRNA-503/cyclin D1 axis. The results of real-time quantitative PCR confirmed that LINC00460 was significantly upregulated in cancer tissues and was associated with poor survival of patients with PC. The expression levels of LINC00460 were significantly associated with tumor size, but not with age, sex, differentiation, lymph node metastasis, vascular invasion and tumor stage. Through univariate and multivariate analysis, LINC00460 was characterized as an independent prognostic biomarker for PC. Further in vitro experiments demonstrated that suppressing LINC00460 using small interfering RNA inhibited viability and colony formation of PC cells. In summary, LINC00460 may be an independent prognostic biomarker for PC and may serve as an oncogenic lncRNA that promotes PC cell growth. Further in-depth exploration is required to reveal the specific biological mechanism of LINC00460 in PC cells.

Long non-coding RNA DDX11-AS1 promotes non-small cell lung cancer development via regulating PI3K/AKT signalling

Non-small cell lung cancer (NSCLC) has been considered to be the most common category of lung cancer, comprising approximately 80% of lung cancers. Long non-coding RNAs (lncRNAs) were diffusely documented to modulate carcinogenesis or progression of tumours. However, the role of DDX11-AS1 was still unclear in NSCLC. Bioinformatics analysis and experimental assays including hematoxylin and eosin (H&E) staining, RT-qPCR, colony formation, CCK-8, flow cytometry, western blot and xenograft assays were applied to investigate the biological role and molecular mechanism of DDX11-AS1 in NSCLC. The level of lncRNA DDX11-AS1 was up-regulated in NSCLC tumour tissues and cells. In function aspect, knockdown of DDX11-AS1 caused an apparent inhibitive effect on cell proliferation in vitro and in vivo. DDX11-AS1 inhibition promoted cell apoptosis in vitro. In mechanism, the protein level of phosphorylated AKT was reduced by DDX11-AS1 inhibition but increased by DDX11-AS1 overexpression. These results indicated that DDX11-AS1 exacerbated NSCLC progression via activating PI3K/AKT signalling pathway. All in all, DDX11-AS1 promotes NSCLC development via regulating PI3K/AKT signalling.

Suppression of LINC00460 mediated the sensitization of HCT116 cells to ionizing radiation by inhibiting epithelial-mesenchymal transition

Radiation resistance is the most common challenge for improving radiotherapy. The mechanisms underlying the development of radioresistance remain poorly understood. This study aims to explore the role of LINC00460 in ionizing radiation-induced radioresistance as well as the mechanisms by which LINC00460 is regulated by radiation exposure. The expression of LINC00460 was measured. Cell proliferation and colony formation were measured in HCT116 cells after treatment by radiation. The development of epithelial-mesenchymal transition (EMT) was determined with or without knockdown LINC00460 expression using western blot analysis. Transcription activity was determined using a series of LINC00460-promoter luciferase reporter gene vectors. LINC00460 expression was significantly higher in HCT116 cells, relative to other cell types, with LINC00460 expression significantly affecting HCT116 cell proliferation. Suppression of LINC00460 inhibits EMT development in HCT116 cells via regulation of ZEB1 expression. Furthermore, LINC00460 expression was induced by irradiation via the activation of c-jun transcription factor-binding element located on the LINC00460 promoter. LINC00460 was shown to play a crucial role in EMT-associated progression of colorectal cancer, indicating that LINC00460 may be an indicator or new potential therapeutic target for colorectal cancer radiosensitization.

LINC01980 facilitates esophageal squamous cell carcinoma progression via regulation of miR-190a-5p/MYO5A pathway

Understanding the role of Long non-coding RNAs (lncRNAs) in tumorigenesis in diverse human malignancies would helpful for targeted therapies, containing esophageal squamous cell carcinoma (ESCC). However, the specific role and molecular mechanisms of LINC01980 in ESCC remain unclarified. In this study, we investigated the expression level, function role, and molecular mechanisms of LINC01980 in esophageal cancer cells and ESCC tissues. The high expression of LINC01980 was detected in ESCC tissues and cells, and predicted poor prognosis. LINC01980 promoted the cell proliferation, migration, invasion ability and epithelial-mesenchymal transition (EMT) progress in ESCC cells. In addition, a negative correlation between LINC01980 and miR-190a-5p or miR-190a-5p and MYO5A was observed in ESCC. We found that miR-190a-5p could directly bind with the mRNA of LINC01980 and MYO5A, and it was detected low expression in ESCC. We further demonstrated that the downregulation of MYO5A caused by overexpressing miR-190a-5p was released via upregulation of LINC01980. Functionally, LINC01980 acted as a competitively endogenous RNA (ceRNA) to impact the expression of MYO5A by sponging miR-190a-5p in ESCC. Therefore, these findings suggest that LINC01980 may act as an oncogenic lncRNA in ESCC and LINC01980/miR-190a-5p/MYO5A pathway contributes to the development of ESCC.

LINC00460 accelerates progression of ovarian cancer by activating transcriptional factor ZNF703

Potential function of LINC00460 in the progression of ovarian cancer (OC) and its underlying mechanism were studied. LINC00460 level in OC tissues and normal ovarian tissues was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Correlation between LINC00460 level with tumor stage, tumor size and pathological subtypes of OC was analyzed. Potential influence of LINC00460 on proliferative ability and cell cycle progression was evaluated. In vivo tumorigenesis model was conducted by administration of A2780 cells transfected with sh-NC or sh-LINC00460 in nude mice. Predicted through JASPAR database, ZNF703 was screened out as the transcriptional factor binding to LINC00460 promoter region. Chromatin immunoprecipitation (ChIP) assay was performed to verify the binding relationship between ZNF703 and LINC00460. The potential role of ZNF703 in LINC00460-mediated OC progression was examined. LINC00460 was upregulated in OC tissues and cell lines. Its level increased with the deterioration of tumor stage and enlargement of tumor size. LINC00460 was highly expressed in serous ovarian cancer relative to other subtypes of OC. Knockdown of LINC00460 attenuated proliferative ability and arrested cell cycle of A2780 and HO8910 cells. ZNF703 was upregulated in OC tissues. ChIP assay showed pronounced enrichment of LINC00460 in ZNF703. Rescue experiments revealed that ZNF703 overexpression reversed the regulatory effects of LINC00460 on cellular behavior of OC cells. LINC00460 is upregulated in OC tissues and cell lines, which is closely related to tumor progression. It accelerates proliferative ability and cell cycle progression of OC cells via interacting with ZNF703.

Long noncoding RNA, LINC00460, as a prognostic biomarker in head and neck squamous cell carcinoma (HNSCC)

Head and neck squamous cell carcinoma (HNSCC) is an aggressive epithelial malignancy characterized by frequent mutations and metastasis. Long noncoding RNAs (lncRNAs) have been implicated in tumorigenesis and serve as novel prognostic biomarkers in different cancers. To enhance our understanding of lncRNAs that may have biological significance in HNSCC and may serve as prognostic biomarkers, we globally profiled lncRNAs in HNSCC by analyzing the RNA-seq data from The Atlas of Noncoding RNAs in Cancer (TANRIC) database. Of 3576 lncRNAs, we identified 926 (higher-688, lower-238) lncRNAs with a 2-fold abundance difference among the forty HNSCC and paired adjacent normal tissue. We investigated differential abundance of lncRNAs based on TP53 mutation and p16 status. We found 133 lncRNAs to have differential abundance by 2-fold among the mutant vs wild-type TP53 samples, whereas among p16-negative vs positive samples, we identified 710 lncRNAs with the same criteria. Meanwhile, analysis of the 15 most abundant lncRNAs in the tumor samples identified five lncRNAs whose higher abundance was associated with poor overall patient survival. Among these five, higher abundance of LINC00460 associated with poor patient survival in an independent cohort of 82 HNSCC patients. To further evaluate the potential function of LINC00460, we performed lncRNA-mRNAs co-expression analysis and found that higher abundance of LINC00460 associated with cancer-related biological pathways including EMT and other inflammatory response pathways. In summary, we report LINC00460 is more abundant in tumors compared to adjacent normal tissue and that it may serve as a potential prognostic biomarker in HNSCC.

Prognostic significance of LINC00460 overexpression in solid tumours: a meta-analysis

The prognostic value of long intergenic non-protein coding RNA 460 (LINC00460) overexpression in human solid malignant tumours remains unclear. Therefore, we conducted the meta-analysis to systematically review and assess the evidence for the correlation between LINC00460 overexpression and clinicopathological features and overall survival (OS) of patients with solid malignant tumour. An electronic search of PubMed, EMBASE, Web of Science, CNKI, Cochrane Library, Chinese Biological Medical Literature database and WanFang database was applied to select eligible articles. Pooled ORs or HRs with their 95% CIs were calculated to estimate the effects. 9 eligible studies with a total of 935 patients were enrolled in this meta-analysis. The results revealed that high LINC00460 expression was associated with positive lymph node metastasis (positive vs negative: OR=2.97, 95% CI 1.74 to 5.05, p=0.812), advanced tumour-node-metastasis stage (III+IV vs I+II: OR=2.82, 95% CI 1.64 to 4.85, p=0.193) and poorer differentiation (high vs low: OR=0.60, 95% CI 0.36 to 0.99, p=0.569). Additionally, the overexpression of LINC00460 could predict a poorer OS (HR=1.57, 95% CI 1.39 to 1.77) and the shorter disease-free survival (HR=2.32, 95% CI 1.25 to 4.31). Furthermore, according to subgroup analysis and meta-regression results, the heterogeneity of current meta-analysis may be attributed to the differences of cancer type and follow-up months. High expression of LINC00460 could predict poor prognosis in patients with solid malignant tumour. LINC00460 may serve as potential prognostic biomarker for clinical outcomes in various human solid malignant tumours.

Down-Regulation of LINC00460 Represses Metastasis of Colorectal Cancer via WWC2

BACKGROUND

Colorectal cancer (CRC) is one of the most prevalent cancers and a common cause of cancer-related death. Long noncoding RNAs have been reported to play an essential role in the development of CRC.

AIMS

This study aimed to investigate the possible function of LINC00460 in CRC.

METHODS

Initially, microarray-based gene expression profiling of CRC was employed to identify differentially expressed genes. Next, the expression of LINC00460 was examined and the cell line presenting with the highest LINC00460 expression was selected for subsequent experimentation. Then, the interaction among LINC00460, ERG, and WWC2 was identified. The effect of LINC00460 on proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT)-related factors as well as tumorigenicity of transfected cells was examined with gain- and loss-of-function experiments.

RESULTS

LINC00460 was robustly induced while WWC2 was poorly expressed in CRC. In addition, LINC00460 could down-regulate WWC2 through interaction with ERG, which led to promoted invasion, migration, and EMT of CRC cells in addition to tumor growth in vivo. Besides, down-regulation of LINC00460 exerted inhibitory effect on these biological activities.

CONCLUSION

Taken together, the key findings of the current study provided evidence suggesting that silencing of LINC00460 could potentially suppress EMT of CRC cells by increasing WWC2 via ERG, and highlighting that knockdown of LINC00460 could serve as a therapeutic target for CRC treatment.

Identification of BRMS1L as Metastasis Suppressing Gene in Esophageal Squamous Cell Carcinoma

Introduction

Breast cancer metastasis suppressor 1 like (BRMS1-like)was first reported to be a component of the Sin3-HDAC complex, but the role in the progression of cancers was largely unknown. Our previous study reported that BRMS1L promoted the metastasis of breast cancer through facilitating the recruitment of HDAC complex to the promoter FZD10, and hence suppressing the transcription of FZD10.

Methods

In this study, we detected the expression level of BRMS1L in esophageal squamous cell carcinoma (ESCC). The effect of BRMS1L in TE-1D (knockdown) and ECA-109 (overexpression) cell lines was explored by transwell assays, wound healing assays, and cell adhesion assays. Quantitative real‑time PCR, Western blot analysis, and luciferase assays were used to detect the interaction of the CBP/P300-BRMS1L-ITGA7 axis.

Results

In the present study, we found that knockdown of BRMS1L promoted the migration, invasion, and epithelial-mesenchymal transition (EMT). Conversely, overexpression of BRMS1L inhibited the migration and invasion of ESCC. Mechanistically, BRMS1L exerted their metastasis-suppressing role via transcriptionally repress ITGA7 expression. Moreover, we revealed that CBP/p 300 regulated the expression of BRMS1L and might be responsible for the down-regulation of BRMS1L in ESCC.

Conclusion

Collectively, we identified the role of CBP/p300-BRMS1L-ITGA7 axis in the metastasis of ESCC.

Comprehensive Analysis of Competitive Endogenous RNAs Network, Being Associated With Esophageal Squamous Cell Carcinoma and Its Emerging Role in Head and Neck Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is a common malignancy with poor prognosis and survival rate. To identify meaningful long non-coding RNA (lncRNA), microRNA (miRNA), and messenger RNA (mRNA) modules related to the ESCC prognosis, The Cancer Genome Atlas-ESCC was downloaded and processed, and then, a weighted gene co-expression network analysis was applied to construct lncRNA co-expression networks, miRNA co-expression networks, and mRNA co-expression networks. Twenty-one hub lncRNAs, seven hub miRNAs, and eight hub mRNAs were clarified. Additionally, a competitive endogenous RNAs network was constructed, and the emerging role of the network involved in head and neck squamous cell carcinoma (HNSCC) was also analyzed using several webtools. The expression levels of eight hub genes (TBC1D2, ATP6V0E1, SPI1, RNASE6, C1QB, C1QC, CSF1R, and C1QA) were different between normal esophageal tissues and HNSCC tissues. The expression levels of TBC1D2 and ATP6V0E1 were related to the survival time of HNSCC. The competitive endogenous RNAs network might provide common mechanisms involving in ESCC and HNSCC. More importantly, useful clues were provided for clinical treatments of both diseases based on novel molecular advances.

Long Noncoding RNA LINC00460 Modulates MMP-9 to Promote Cell Proliferation, Invasion and Apoptosis by Targeting miR-539 in Papillary Thyroid Cancer

BACKGROUND

Increasing evidence shows that Long non-coding RNAs (lncRNAs) involve in the development and progression processes of various cancers, including papillary thyroid cancer (PTC). In this study, we focused on the regulation function of lncRNA LINC00460 in the development of PTC.

METHODS

Expression of LINC00460 was detected using quantitative real-time PCR (qRT-PCR) and Western blot assay. Cell proliferation, cell apoptosis and cell invasion were determined through CCK-8 assay, flow cytometry, and Transwell assay, respectively. In addition, target sites were detected by the dual-luciferase reporter gene assay.

RESULTS

LINC00460 expression was markedly up-regulated in PTC tissues and cells compared to their corresponding controls by quantitative real-time PCR (qRT-PCR). Meanwhile, LINC00460 knockdown notably inhibited the proliferation capacity, accelerated the apoptosis and down-regulated the invasion-related proteins (MMP-2, MMP-9, ZEB1) expression. In addition, bioinformatics tools predicted that miR-539 both targeted with the 3'-UTR of LINC00460 and MMP-9, which was confirmed by luciferase reporter assay and Western blot.

CONCLUSION

These findings indicated that LINC00460 can modulate MMP-9 expression to promote cell proliferation, invasion and apoptosis through targeting miR-539, suggesting act as an oncogenic RNA in PTC and provide a new therapeutic perspective.

The exploration of new therapeutic targets for HPV-negative head and neck squamous cell cancer through the construction of a ceRNA network and immune microenvironment analysis

Previous studies have shown that human papillomavirus (HPV)-negative patients with head and neck squamous cell cancer (HNSCC) suffer from an unsatisfactory prognosis. Long noncoding RNAs (lncRNAs) have been verified to participate in many biological processes, including regulating gene expression as competing endogenous RNAs (ceRNAs), while few studies focused the ceRNA network regulation mechanism in patients with HPV-negative HNSCC tumor. Meanwhile, the immune microenvironment may be critical in the development and prognosis of HPV-negative tumors. Our study aimed to further investigate the pathogenesis and potential biomarkers for the diagnosis, therapy and prognosis of HPV-negative HNSCC through a ceRNA network. Comprehensively analyzing the sequencing data of lncRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs) in The Cancer Genome Atlas HNSCC dataset, we constructed a differentially expressed ceRNA network containing 131 lncRNAs, 35 miRNAs and 162 mRNAs. Then, survival analysis in the network was cited to explore the prognostic biomarkers. Eight mRNAs, nine lncRNAs, and one miRNA were identified to be associated with prognosis. Neuropilin (NRP) binding function, retinoid X receptor (RXR) binding, and the vascular endothelial growth factor (VEGF) signaling pathway were associated with the enrichment analysis, and they also related to the immune microenvironment. Combined with the analysis of the immune microenvironment differences, we obtained new targeted therapies using an RXR agonist, or a combination of the VEGF monoclonal antibody and an NRP antagonist, which may provide a promising future for HPV-negative HNSCC patients.

Garcinol inhibits esophageal cancer metastasis by suppressing the p300 and TGF-β1 signaling pathways

Metastasis causes the main lethality in esophageal cancer patient. Garcinol, a natural compound extracted from Gambogic genera, is a histone acetyltransferase (HAT) inhibitor that has shown anticancer activities such as cell cycle arrest and apoptosis induction. In this study, we investigated the effects of garcinol on the metastasis of esophageal cancer in vitro and in vivo. We found that garcinol (5–15 μM) dose-dependently inhibited the migration and invasion of human esophageal cancer cell lines KYSE150 and KYSE450 in wound healing, transwell migration, and Matrigel invasion assays. Furthermore, garcinol treatment dose-dependently decreased the protein levels of p300/CBP (transcriptional cofactors and HATs) and p-Smad2/3 expression in the nucleus, thus impeding tumor cell proliferation and metastasis. Knockdown of p300 could inhibit cell metastasis, but CBP knockdown did not affect the cell mobility. It has been reported that TGF-β1 stimulated the phosphorylation of Smad2/3, which directly interact with p300/CBP in the nucleus, and upregulating HAT activity of p300. We showed that garcinol treatment dose-dependently suppressed TGF-β1-activated Smad and non-Smad pathway, inhibiting esophageal cancer cell metastasis. In a tail vein injection pulmonary metastasis mouse model, intraperitoneal administration of garcinol (20 mg/kg) or 5-FU (20 mg/kg) significantly decreased the number of lung tumor nodules and the expression levels of Ki-67, p300, and p-Smad2/3 in lung tissues. In conclusion, our study demonstrates that garcinol inhibits esophageal cancer metastasis in vitro and in vivo, which might be related to the suppression of p300 and TGF-β1 signaling pathways, suggesting the therapeutic potential of Garcinol for metastatic tumors.

Long intergenic non‑protein coding RNA 00460 predicts a poor prognosis and promotes tumorigenesis of human osteosarcoma

Osteosarcoma (OS) is the most common type of primary malignant bone tumor, which has a high incidence rate in children and adolescents. This research aims to reveal the role of long intergenic non‑protein coding RNA 00460 (LINC00460) in OS by the loss‑of‑function experiment. LINC00460 is involved in the development of multiple types of tumor, but the role of LINC00460 in OS is unclear. To discover more effective molecular targets for the treatment of OS, the association between LINC00460 and OS prognosis was analyzed using the Gene Expression Profiling Interactive Analysis database. Additionally, small interfering RNA was used to knockdown LINC00460 gene expression in vitro to verify its biological effects on the viability, invasive and migratory potential of OS cells. LINC00460 knockdown significantly reduced the viability of OS cells and initiated cell cycle arrest within the G0/G1 phase through the decreased expression of cyclin D1 and CDK4/CDK6. In addition, LINC00460 knockdown promoted apoptosis of OS cells, and inhibited the migratory and invasive abilities of OS cells through the inhibition of the epithelial‑mesenchymal transition pathway. In conclusion, the present study reported that LINC00460 may predict OS prognosis, and may serve an important role in mediating the viability, invasive and migratory potential of OS cells. Based on these findings, LINC00460 demonstrated promising potential as a future therapeutic target for OS treatment.

Long non-coding RNA LINC00460 promotes head and neck squamous cell carcinoma cell progression by sponging miR-612 to up-regulate AKT2

LncRNAs (long noncoding RNAs) have been shown to be potentially critical regulators in head and neck squamous cell carcinoma (HNSCC). LncRNA LINC00460 (long intergenic non-protein coding RNA 460), an "oncogene", regulates progression of various tumors. However, the tumorigenic mechanism of LINC00460 on HNSCC is yet to be investigated. In the current study, we discovered that LINC00460 was relatively up-regulated in both HNSCC cancer tissues and cell lines, and predicted a poor prognosis in HNSCC patients. Gain- and loss-of functional studies established that over-expression of LINC00460 promoted cell proliferation, invasion and migration of HNSCC cells in vitro, while the promotion abilities were suppressed via knockdown of LINC00460. Our results identified miR-612 as a novel target of LINC00460, whose expression suggested a negative correlation with LINC00460 in HNSCC tissues and cell lines. LINC00460 increased the expression of serine/threonine kinase AKT2 via sponging miR-612. Rescue experiments indicated that LINC00460 could promote HNSCC progression partially through inhibition of miR-612. Subcutaneous xenotransplanted tumor model confirmed that interference of LINC00460 suppressed in vivo tumorigenic ability of HNSCC via down-regulation of AKT2. In conclusion, our findings clarified the biologic significance of LINC00460/miR-612/AKT2 axis in HNSCC progression and provided novel evidence that LINC00460 may be a new potential therapeutic target for HNSCC.

LncRNA LINC00460 promotes EMT in head and neck squamous cell carcinoma by facilitating peroxiredoxin-1 into the nucleus

BACKGROUND

The lncRNA LINC00460 plays crucial roles in several epithelial cancers, although its mechanisms of action differ greatly in different cellular contexts. In this study, we aimed to determine the potential clinical applications of LINC00460 and elucidate the mechanisms by which LINC00460 affects the development and progression of head and neck squamous cell carcinoma (HNSCC).

METHODS

The biological functions of LINC00460 were assessed in several epithelial cancer cell lines. The subcellular localization of LINC00460 was evaluated by cell nuclear/cytoplasmic fractionation and fluorescence in situ hybridization. RNA pull-down assays, LS-MS/MS analysis, and RNA and chromatin immunoprecipitation assays were performed to identify the molecular mechanism by which LINC00460 promotes HNSCC progression. The clinical pathological features of LINC00460 and PRDX1 were evaluated in HNSCC tissues and paired adjacent normal tissues.

RESULTS

LINC00460 enhanced HNSCC cell proliferation and metastasis in vitro and in vivo and induced epithelial-mesenchymal transition (EMT). LINC00460 primarily localized within the cytoplasm of HNSCC cells, physically interacted with PRDX1 and facilitated PRDX1 entry into the nucleus. PRDX1 promoted the transcription of LINC00460, forming a positive feedback loop. In addition, PRDX1 also promoted the transcription of EMT-related genes (such as ZEB1, ZEB2 and VIM) through enrichment on gene promoters in the nucleus. LINC00460 effectively induced HNSCC cell EMT in a PRDX1-dependent manner, and PRDX1 mainly mediated the EMT-promoting effect of LINC00460. High levels of LINC00460 and PRDX1 expression were positively associated with lymph metastasis, pathological differentiation and tumor size in HNSCC patients.

CONCLUSIONS

LINC00460 promoted EMT in HNSCC cells by facilitating PRDX1 entry into the nucleus. LINC00460 and PRDX1 are promising candidate prognostic predictors and potential targets for cancer therapy for HNSCC.

Involvement of noncoding RNAs in epigenetic modifications of esophageal cancer

Esophageal cancer (EC) is a serious digestive malignancy and is a leading cause of cancer-related mortality. Apart from genetic mutations, many epigenetic alterations including DNA methylation and histone modifications associated with chromatin remodeling have been identified in the regulation of gene expression in EC. Recently, noncoding RNAs, and mainly lncRNAs and miRNAs, have been revealed to be involved in the epigenetic regulation of EC. In this review, we focus on describing new insights on epigenetic processes associated with noncoding RNAs, which have been characterized to be responsible for the development and progression of EC.

Long noncoding RNA Linc00460 promotes breast cancer progression by regulating the miR-489-5p/FGF7/AKT axis

Purpose: Evidence indicates that long noncoding RNAs (lncRNA) possess important roles in various cellular processes and that dysregulation of lncRNAs promotes tumor progression. However, the expression patterns and biological functions of many specific lncRNAs in breast cancer remain to be determined. Methods: Quantitative real-time polymerase chain reaction was performed to detect Linc00460, miR-489-5p and FGF7 expression. Protein levels were determined using Western blot. MTT and colony formation assay were used to measure cell proliferation. Transwell assays were conducted to determine cell migration and invasion. Luciferase reporter assays were carried out to assess the interaction between miR-489-5p and Linc00460 or FGF7. Biotin pull-down assay was used to detect the direct interaction between miR-489-5p and Linc00460. In vivo experiments were performed to measure tumor formation and lung metastasis. Results: We demonstrated that lncRNA Linc00460 was upregulated in breast cancer, and its expression level was positively associated with lymphatic metastasis and poor overall survival. Forced expression of Linc00460 increased, whereas Linc00460 silencing decreased, breast cancer cell viability, migration and invasion both in vitro and in vivo. Linc00460 was identified as a direct target of miR-489-5p, which further targeted FGF7 and exerted oncogenic functions in breast cancer. Mechanistically, Linc00460 served as a competing endogenous RNA of FGF-7 mRNA by sponging miR-489-5p, resulting in upregulated FGF7 expression and AKT activity. Notably, forced expression of miR-489-5p abrogated Linc00460-mediated oncogenic behavior and activation of the FGF7-AKT pathway in breast cancer cells. Conclusion: We have demonstrated that Linc00460 promotes breast cancer progression partly through the miR-489-5p/FGF7/AKT axis.

Nicotine promotes the development of non-small cell lung cancer through activating LINC00460 and PI3K/Akt signaling

Objective: Nicotine, the main ingredient in tobacco, is identified to facilitate tumorigenesis and accelerate metastasis in tumor. Studies in recent years have reported that long intergenic non-protein coding RNA 460 (LINC00460) is strongly associated with lung cancer poor prognosis and nicotine dependence. Nonetheless, it is unclear whether nicotine promotes the development of lung cancer through activation of LINC00460. Methods: We determined that LINC00460 expression in lung cancer tissues and the prognosis in patients with non-small cell lung carcinoma (NSCLC) using Gene Expression Profiling Interactive Analysis (GEPIA) website and The Cancer Genome Atlas (TCGA) database. Through in vitro experiments, we studied the effects of nicotine on LINC00460 in NSCLC cells lines using Cell Counting Kit-8 (CCK-8), transwell test, flow cytometry, quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Western blot assays. Results: We identified the significant up-regulated expression level of LINC00460 in NSCLC tissues and cell lines, especially, the negative correlation of LINC00460 expression level with overall survival (OS). In in vitro experiments, LINC00460 was overexpressed in NSCLC cell lines under nicotine stimulation. Nicotine could relieve the effect of LINC00460 knockdown on NSCLC cell proliferation, migration and apoptosis. The same influence was observed on PI3K/Akt signaling pathway. Conclusions: In summary, this is the first time to examine the potential roles of LINC00460 in lung cancer cell proliferation, migration and apoptosis induced by nicotine. This may help to develop novel therapeutic strategies for the prevention and treatment of metastatic tumors from cigarette smoke-caused lung cancer by blocking the nicotine-activated LINC00460 pathway.

Long noncoding RNA 00460 (LINC00460) promotes glioma progression by negatively regulating miR-320a

Objective

Long noncoding RNA 00460 (LINC00460) has been reported to contribute to tumorigenesis in multiple types of human malignancies. However, the biological role and the underlying molecular mechanism of LINC00460 in glioma remain unclear. The aim of this study was to investigate the clinical value, the biological function, and the potential mechanism of LINC00460 in glioma.

Methods

The expression level of LINC00460 in glioma tissues and cell lines was examined by quantitative real‐time polymerase chain reaction (qRT‐PCR). Cell Counting Kit‐8, flow cemetery, wound healing, and transwell invasion assays were used to explore the effect of LINC00460 on glioma cell proliferation, apoptosis, migration, and invasion. qRT‐PCR and reporter assays were used to further verify the regulatory mechanism of LINC00460 in glioma progression.

Results

LINC00460 expression was upregulated in glioma tissues and cell lines compared with non–tumor brain samples and astrocyte cell line (NHA), respectively. Moreover, increased LINC00460 expression was closely associated with glioma tumor grade. Loss‐of‐function assays revealed that knockdown of LINC00460 significantly inhibited glioma cell proliferation, induced cell apoptosis, and suppressed migration and invasion. The mechanistic assays disclosed that LINC00460 binded to miR‐320a in a sequence‐specific manner and regulated its expression. Moreover, miR‐320 inhibition partially attenuated LINC00460 knockdown‐mediated suppressive effects on glioma cell proliferation, migration, and invasion.

Conclusion

These findings suggested that LINC00460 might function as an oncogenic lncRNA in glioma development and could be explored as a potential therapeutic target for glioma.