Long intergenic non-coding RNA 00152 promotes tumor cell cycle progression by binding to EZH2 and repressing p15 and p21 in gastric cancer

The prognostic, diagnostic, and therapeutic impact of Long noncoding RNAs in gastric cancer

Gastric cancer (GC), ranking as the third deadliest cancer globally, faces challenges of late diagnosis and limited treatment efficacy. Long non-coding RNAs (lncRNAs) emerge as valuable treasured targets for cancer prognosis, diagnosis, and therapy, given their high specificity, convenient non-invasive detection in body fluids, and crucial roles in diverse physiological and pathological processes. Research indicates the significant involvement of lncRNAs in various aspects of GC pathogenesis, including initiation, metastasis, and recurrence, underscoring their potential as novel diagnostic and prognostic biomarkers, as well as therapeutic targets for GC. Despite existing challenges in the clinical application of lncRNAs in GC, the evolving landscape of lncRNA molecular biology holds promise for advancing the survival and treatment outcomes of gastric cancer patients. This review provides insights into recent studies on lncRNAs in gastric cancer, elucidating their molecular mechanisms and exploring the potential clinical applications in GC.

EZH2-interacting lncRNAs contribute to gastric tumorigenesis; a review on the mechanisms of action

Gastric cancer (GC) remains one of the deadliest malignancies worldwide, demanding new targets to improve its diagnosis and treatment. Long non-coding RNAs (lncRNAs) are dysregulated through gastric tumorigenesis and play a significant role in GC progression and development. Recent studies have revealed that lncRNAs can interact with histone-modifying polycomb protein, enhance Zeste Homolog 2 (EZH2), and mediate its site-specific functioning. EZH2, which functions as an oncogene in GC, is the catalytic subunit of the PRC2 complex that induces H3K27 trimethylation and epigenetically represses gene expression. EZH2-interacting lncRNAs can recruit EZH2 to the promoter regions of various tumor suppressor genes and cause their transcriptional deactivation via histone methylation. The interactions between EZH2 and this lncRNA modulate different processes, such as cell cycle, cell proliferation and growth, migration, invasion, metastasis, and drug resistance, in vitro and in vivo GC models. Therefore, EZH2-interacting lncRNAs are exciting targets for developing novel targeted therapies for GC. Subsequently, this review aims to focus on the roles of these interactions in GC progression to understand the therapeutic value of EZH2-interacting lncRNAs further.

A review on the role of LINC00152 in different disorders

LINC00152 is an important lncRNA in human disorders. It is mainly regarded as a tumor-promoting lncRNA. Mechanistically, LINC00152 serves as a molecular sponge for miR-143a-3p, miR-125a-5p, miR-139, miR-215, miR-193a/b-3p, miR-16-5p, miR-206, miR-195, miR-138, miR-185-5p, miR-103, miR-612, miR-150, miR-107, miR-205-5p and miR-153-3p. In addition, it can regulate activity of mTOR, EGFR/PI3K/AKT, ERK/MAPK, Wnt/β-Catenin, EGFR, NF-κB, HIF-1 and PTEN. In this review, we provide a concise but comprehensive explanation about the role of LINC00152 in tumor development and progression as well as its role in the pathology of non-malignant conditions with the aim of facilitating the clinical implementation of this lncRNA as a diagnostic or prognostic tumor marker and therapeutic target.

Thermodynamic and structural characterization of an EBV infected B-cell lymphoma transcriptome

Epstein-Barr virus (EBV) is a widely prevalent human herpes virus infecting over 95% of all adults and is associated with a variety of B-cell cancers and induction of multiple sclerosis. EBV accomplishes this in part by expression of coding and noncoding RNAs and alteration of the host cell transcriptome. To better understand the structures which are forming in the viral and host transcriptomes of infected cells, the RNA structure probing technique Structure-seq2 was applied to the BJAB-B1 cell line (an EBV infected B-cell lymphoma). This resulted in reactivity profiles and secondary structural analyses for over 10000 human mRNAs and lncRNAs, along with 19 lytic and latent EBV transcripts. We report in-depth structural analyses for the human MYC mRNA and the human lncRNA CYTOR. Additionally, we provide a new model for the EBV noncoding RNA EBER2 and provide the first reported model for the EBV tandem terminal repeat RNA. In-depth thermodynamic and structural analyses were carried out with the motif discovery tool ScanFold and RNAfold prediction tool; subsequent covariation analyses were performed on resulting models finding various levels of support. ScanFold results for all analyzed transcripts are made available for viewing and download on the user-friendly RNAStructuromeDB.

The LINC00152/miR-205-5p/CXCL11 axis in hepatocellular carcinoma cancer-associated fibroblasts affects cancer cell phenotypes and tumor growth

BACKGROUND

CXCL11 has been reported to be up-regulated in hepatocellular carcinoma (HCC) tissues and cancer-associated fibroblasts (CAFs), and CAF-secreted CXCL11 has been found to promote HCC cell proliferation and migration. Knowledge on how CAFs promote HCC progression is imperative for the future design of anti-tumor drugs addressing the high rates of disease recurrence. Herein, we propose a mechanism by which LINC00152 positively regulates CXCL11 expression and, subsequently, HCC cell phenotypes and growth characteristics via miR-205-5p in CAFs.

METHODS

The expression of LINC00152, miR-205-5p in HCC/non-cancerous tissues, CAFs/NFs and HCC cell lines was determined by RT-qPCR. The CXCL11 expression and secretion were determined by westernblot and ELISA. Different expressions of LINC00152, CXCL11 and miR-205-5p in CAFs were achieved by transfection with corresponding overexpression/knockdown vectors or mimics/inhibitor. The interactions among LINC00152, miR-205-5p and CXCL11 were confirmed by FISH, luciferase, AGO2 and RNA-pulldown assays. Transwell, colony formation and MTT assays were performed to assess the role of CAFs conditioned medium (CM) in HCC cell phenotype. BALB/c nude mice xenografts were used to determine the role of CAFs on HCC growth in vivo.

RESULTS

We found that in vitro, CM from CAFs transfected with sh-LINC00152 dramatically suppressed HCC cell viability, colony formation and migration, and that CM from CAFs transfected with miR-205-5p inhibitor (CAF-CM (miR-205-5p inhibitor)) exerted opposite effects on HCC cell phenotypes. Exogenous overexpression of CXCL11 in CAFs or CAF-CM (miR-205-5p inhibitor) could partially attenuate the effects of LINC00152 knockdown. In contrast, CM from CAFs transfected with LINC00152 dramatically increased HCC cell viability, colony formation and migration, and CM from CAFs transfected with miR-205-5p mimics (CAF-CM (miR-205-5p mimics)) exerted opposite effects on HCC cell phenotypes. Knockdown of CXCL11 in CAFs or CAF-CM (miR-205-5p mimics) could partially attenuate the effects of LINC00152 overexpression. In vivo, LINC00152 knockdown in CAFs inhibited tumor growth in a mouse model, which could be reversed by CXCL11 overexpression in CAFs. Mechanistically, we found that LINC00152 could act as a ceRNA to counteract miR-205-5p-mediated suppression on CXCL11 by directly binding to miR-205-5p and the 3'UTR of CXCL11.

CONCLUSION

Our data indicate that a LINC00152/miR-205-5p/CXCL11 axis in HCC CAFs can affect the proliferative and migrative abilities of HCC cells in vitro and HCC tumor growth in vivo.

Abnormally Expressed lncRNAs as Potential Biomarkers for Gastric Cancer Risk: A Diagnostic Meta-Bioinformatics Analysis

Background and Aims

Abnormal expression of lncRNAs is relevant to the occurrence and development of gastric cancer (GC), but the significance remains inconclusive. We performed a diagnostic meta-bioinformatics analysis to elucidate the association between lncRNA expression and GC risk.

Methods

Published datasets were selected from PubMed, Embase, CNKI, and Web of Science, up to 1st December 2021. The pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated to evaluate the diagnostic value. RNA sequencing data were downloaded for validation.

Results

54 studies with 4671 patients and 4652 matched controls were included in the meta-analysis. The pooled SEN, SPE, PLR, NLR, DOR, and AUC were 0.71, 0.76, 2.9, 0.39, 8, and 0.79, respectively. Subgroup analyses showed that the DOR and AUC of intergenic lncRNAs, circulating lncRNAs, larger sample size (>200), and high-quality (NOS score ≥ 7) groups were superior to antisense lncRNAs, tissue lncRNAs, smaller sample size (≤200), and low-quality (NOS score < 7) groups, respectively. However, only circulating lncRNAs had significantly higher diagnostic utility than that tissue lncRNAs. Nine differentially expressed lncRNAs in the meta-analysis were verified in TCGA-STAD. PVT1 was the most effective single lncRNA, with AUC of 0.949, SEN of 0.808, and SPE of 0.969, while PVT1 and C5orf66-AS1 were the most effective combination, with AUC of 0.972, SEN of 0.941, and SPE of 0.937.

Conclusion

Abnormally expressed lncRNAs, especially circulating lncRNAs, might be potential diagnostic biomarkers for GC risk. A novel combined model of lncRNAs might achieve better GC diagnosis performance.

Identification of immune-related ferroptosis prognostic marker and in-depth bioinformatics exploration of multi-omics mechanisms in thyroid cancer

Background: Factors such as variations in thyroid carcinoma (THCA) gene characteristics could influence the clinical outcome. Ferroptosis and immunity have been verified to play an essential role in various cancers, and could affect the cancer patients’ prognosis. However, their relationship to the progression and prognosis of many types of THCA remains unclear.

Methods: First, we extracted prognosis-related immune-related genes and ferroptosis-related genes from 2 databases for co-expression analysis to obtain prognosis-related differentially expressed immune-related ferroptosis genes (PR-DE-IRFeGs), and screened BID and CDKN2A for building a prognostic model. Subsequently, multiple validation methods were used to test the model’s performance and compare its performance with other 4 external models. Then, we explored the mechanism of immunity and ferroptosis in the occurrence, development and prognosis of THCA from the perspectives of anti-tumor immunity, CDKN2A-related competitive endogenous RNA regulatory, copy number variations and high frequency gene mutation. Finally, we evaluated this model’s clinical practice value.

Results: BID and CDKN2A were identified as prognostic risk and protective factors, respectively. External data and qRT-PCR experiment also validated their differential expression. The model’s excellent performance has been repeatedly verified and outperformed other models. Risk scores were significantly associated with most immune cells/functions. Risk score/2 PR-DE-IRFeGs expression was strongly associated with BRAF/NRAS/HRAS mutation. Single copy number deletion of CDKN2A is associated with upregulation of CDKN2A expression and worse prognosis. The predicted regulatory network consisting of CYTOR, hsa-miRNA-873-5p and CDKN2A was shown to significantly affect prognosis. The model and corresponding nomogram have been shown to have excellent clinical practice value.

Conclusion: The model can effectively predict the THCA patients’ prognosis and guide clinical treatment. Ferroptosis and immunity may be involved in the THCA’s progression through antitumor immunity and BRAF/NRAS/HRAS mutation. CYTOR-hsa-miRNA-873-5p-CDKN2A regulatory networks and single copy number deletion of CDKN2A may also affect THCA′ progression and prognosis.

Identification of Differentially Expressed Long Noncoding RNAs as Functional Biomarkers and Construction of Function Enrichment Network in Oral Squamous Cell Carcinoma

Objective

This study aims to find the novel lncRNAs closely related to the progression of oral squamous cell carcinoma (OSCC) by comprehensively analyzing microarray.

Methods

Chip dataset GSE84805 was downloaded from the Gene Expression Omnibus (GEO) database, lncRNA expression profiles of OSCC and paracancerous tissue were obtained, probes sequences reannotation was conducted, and differentially expressed lncRNAs (DELs) and differentially expressed genes (DEGs) were identified. Finally, these data were analyzed by constructing the lncRNA-function enrichment network.

Results

We found that 465 lncRNAs are differentially expressed consisting of 193 upregulated lncRNAs and 272 downregulated lncRNAs. Meanwhile, 811 DEGs were identified with 498 upregulated genes and 313 downregulated genes. Analysis of the lncRNA-function enrichment network showed that these aberrant lncRNAs may be related to focal adhesion, inflammatory response pathway, cell cycle, matrix metalloproteinases, and other biological functions. Also, we found that some key lncRNAs such as LINC00152 and HOXA11-AS have been shown to play an important role in tumor proliferation and migration.

Conclusion

The key lncRNAs may serve as potential molecular markers or therapeutic targets in OSCC formation and development. It can also help us to understand the molecular mechanism of occurrence and development in OSCC.

LINC00152 Drives a Competing Endogenous RNA Network in Human Hepatocellular Carcinoma

Genomic and epigenomic studies revealed dysregulation of long non-coding RNAs in many cancer entities, including liver cancer. We identified an epigenetic mechanism leading to upregulation of the long intergenic non-coding RNA 152 (LINC00152) expression in human hepatocellular carcinoma (HCC). Here, we aimed to characterize a potential competing endogenous RNA (ceRNA) network, in which LINC00152 exerts oncogenic functions by sponging miRNAs, thereby affecting their target gene expression. Database and gene expression data of human HCC were integrated to develop a potential LINC00152-driven ceRNA in silico. RNA immunoprecipitation and luciferase assay were used to identify miRNA binding to LINC00152 in human HCC cells. Functionally active players in the ceRNA network were analyzed using gene editing, siRNA or miRNA mimic transfection, and expression vectors in vitro. RNA expression in human HCC in vivo was validated by RNA in situ hybridization. Let-7c-5p, miR-23a-3p, miR-125a-5p, miR-125b-5p, miR-143a-3p, miR-193-3p, and miR-195-5p were detected as new components of the potential LINC00152 ceRNA network in human HCC. LINC00152 was confirmed to sponge miR143a-3p in human HCC cell lines, thereby limiting its binding to their respective target genes, like KLC2. KLC2 was identified as a central mediator promoting pro-tumorigenic effects of LINC00152 overexpression in HCC cells. Furthermore, co-expression of LINC00152 and KLC2 was observed in human HCC cohorts and high KLC2 expression was associated with shorter patient survival. Functional assays demonstrated that KLC2 promoted cell proliferation, clonogenicity and migration in vitro. The LINC00152-miR-143a-3p-KLC2 axis may represent a therapeutic target in human HCC.

Identification of EMT-Related lncRNAs as Potential Prognostic Biomarkers and Therapeutic Targets for Pancreatic Adenocarcinoma

Epithelial-mesenchymal transition (EMT) can promote carcinoma progression by multiple mechanisms; many studies demonstrated the invasiveness of pancreatic adenocarcinoma (PAAD) associated with the EMT, but how it acts through an lncRNA-dependent manner is unknown. Here, we investigated 146 samples from The Cancer Genome Atlas (TCGA) and 92 samples from the International Cancer Genome Consortium (ICGC). By gene set variation analysis (GSVA) and weighted correlation network analysis (WGCNA), we explored the EMT-related long noncoding RNAs (EMTlnc). Then, we performed univariate Cox regression analysis to screen their prognostic value for PAAD. The least absolute contraction and selection operator (LASSO) Cox regression was used to establish EMT-related lncRNA prognostic signal (EMT-LPS). In addition, we established a competitive endogenous ceRNA network. Then, we identified 33 prognostic EMTlnc as prognostic lncRNAs and established an EMT-LPS which showed strong prognostic ability in stratification analysis. By corresponding risk scores, patients were divided into low-risk and high-risk subgroups. Principal component analysis (PCA) showed that these subgroups had individual EMT status. Enrichment analysis showed that in the high-risk subgroup, biological processes, pathways, and hallmarks related to malignant tumors are more common. What is more, we constructed a nomogram that had powerful ability to predict the overall survival rate (OS) of PAAD patients in two datasets. So, EMT-LPS are a principal element in PAAD's carcinoma progression and may help us in choosing the way of prognosis assessment and provide some clues to design the new drugs for PAAD.

Interaction of ncRNA and Epigenetic Modifications in Gastric Cancer: Focus on Histone Modification

Gastric cancer has developed as a very common gastrointestinal tumors, with recent effective advancements in the diagnosis and treatment of early gastric cancer. However, the prognosis for gastric cancer remains poor. As a result, there is in sore need of better understanding the mechanisms of gastric cancer development and progression to improve existing diagnostic and treatment options. In recent years, epigenetics has been recognized as an important contributor on tumor progression. Epigenetic changes in cancer include chromatin remodeling, DNA methylation and histone modifications. An increasing number of studies demonstrated that noncoding RNAs (ncRNAs) are associated with epigenetic changes in gastric cancer. Herein, we describe the molecular interactions of histone modifications and ncRNAs in epigenetics. We focus on ncRNA-mediated histone modifications of gene expression associated with tumorigenesis and progression in gastric cancer. This molecular mechanism will contribute to our deeper understanding of gastric carcinogenesis and progression, thus providing innovations in gastric cancer diagnosis and treatment strategies.

PBX1 Participates in Estrogen-mediated Bladder Cancer Progression and Chemo-resistance Affecting Estrogen Receptors

BACKGROUND

Bladder cancer (BCa) is a common cancer associated with high morbidity and mortality worldwide. Pre-B-cell leukemia transcription factor 1 (PBX1) has been reported to be involved in tumor progression.

OBJECTIVE

The aim of the study was to explore the specific role of PBX1 in BCa and its underlying mechanisms.

METHODS

The relative expressions of PBX1 in muscle-invasive BCa tissues and cell lines were analyzed through RT-qPCR and western blotting. Kaplan-Meier analysis was used to analyze the relationship between PBX1 levels and survival status. Co-immunoprecipitation (CO-IP) and chromatin immunoprecipitation (ChIP)-qPCR assays were adopted to verify the interaction between PBX1 and Estrogen receptors (ERs) and explore the estrogen receptors (ERs)-dependent genes transcription.

RESULTS

PBX1 was upregulated in invasive BCa patients and BCa cells, positively associated with tumor size, lymph node metastasis, distant metastasis and poorer survival status. The overexpression of PBX1 promoted cell growth, invasion, epithelial-mesenchymal transition (EMT) process and cisplatin resistance in BCa cells, while the silence of PBX1 showed opposite effects. Furthermore, PBX1 interacted with ERs and was required for ER function. PBX1 overexpression aggravated the tumorpromoting effect of estrogen on BCa cells, while it partially suppressed the inhibitory effects of ER antagonist AZD9496 on BCa cells.

CONCLUSION

This study revealed that PBX1 participated in estrogen mediated BCa progression and chemo-resistance through binding and activating estrogen receptors. Hence, PBX1 may serve as a potential prognostic and therapeutic target for BCa treatment.

Regulatory Mechanism of LINC00152 on Aggravating Heart Failure through Triggering Fibrosis in an Infarcted Myocardium

OBJECTIVE

To elucidate the role of LINC00152 in the progression of heart failure following myocardial infarction. Patients and Methods. Serum levels of LINC00152 in acute myocardial infarction (AMI) patients were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Receiver operating characteristic (ROC) curves were depicted for assessing the diagnostic value of LINC00152 in AMI. Subsequently, an in vivo AMI model was generated in mice. LINC00152 level in a mouse infarcted myocardium was detected. Echocardiogram was conducted to evaluate the influence of LINC00152 on cardiac function in AMI mice. Primary cardiac fibroblasts were isolated from neonatal mice. After knockdown of LINC00152, proliferative and migratory changes in primary cardiac fibroblasts were assessed by cell counting kit-8 (CCK-8) and transwell assay, respectively. The regulatory effect of LINC00152 on Smad7 level was determined by qRT-PCR. Finally, the involvement of Smad7 in LINC00152-regulated proliferative and migratory abilities in primary cardiac fibroblasts was explored by rescue experiments.

RESULTS

Serum level of LINC00152 was elevated in AMI patients. ROC curves demonstrated the diagnostic potential of LINC00152 in AMI (95% CI: 0.806-0.940, p = 0.034). In myocardial tissues collected from AMI mice, LINC00152 level was higher than those collected from mice of the sham group. LVEF and FS markedly decreased in AMI mice overexpressing LINC00152 on the 4th week of AMI modeling. After knockdown of LINC00152 in primary cardiac fibroblasts, proliferative and migratory abilities were declined, which were abolished by Smad7 intervention.

CONCLUSIONS

By downregulating Smad7, LINC00152 aggravates heart failure following AMI via promoting the proliferative and migratory abilities in cardiac fibroblasts.

Long noncoding RNA CYTOR triggers gastric cancer progression by targeting miR-103/RAB10

Growing evidence has indicated that the long noncoding RNA (lncRNA) CYTOR is involved in the initiation and progression of malignancies, including gastric cancer. Nevertheless, the mechanisms of CYTOR in gastric cancer development are not fully understood. In the present study, we aimed to clarify the association of CYTOR, miR-103, and RAB10 in gastric cancer progression. We found that CYTOR expression was increased in metastatic gastric cancer biopsies compared with that in primary samples. CYTOR expression was significantly positively correlated with the invasiveness, lymph node metastasis, and advanced stages of gastric cancer. In addition, downregulation of CYTOR expression hampered cell proliferation and migration but induced cell apoptosis. Furthermore, CYTOR sponged miR-103 and diminished miR-103 expression, thus rescuing oncogene RAB10 expression. Knockdown of CYTOR suppressed tumor growth in human BGC823 mouse models. These findings suggest that the CYTOR/miR-103/RAB10 axis is a novel signaling pathway that facilitates gastric cancer progression. CYTOR-targeted interventions provide a rationale to improve therapies targeting gastric cancer progression.

LncRNA TP73-AS1 promotes the development of Epstein-Barr virus associated gastric cancer by recruiting PRC2 complex to regulate WIF1 methylation

BACKGROUND

Epstein-Barr virus associated gastric cancer (EBVaGC) become a growing health problem. TP73-AS1 showed high expression in EBVaGC cells. However, the function role and underlying mechanism of TP73-AS1 need further exploration.

METHODS

The expressions of TP73-AS1, WIF1, EZH2, β-catenin and epithelial-mesenchymal transition (EMT)-related proteins were detected using qRT-PCR and Western blotting. Cell proliferation, apoptosis, migration and invasion were measured by CCK-8, colony formation, flow cytometry, wound healing and transwell assays, respectively. WIF1 promoter methylation was analyzed by MS-PCR (MSP). RNA immunoprecipitation assay (RIP) and Chromatin immunoprecipitation assay (ChIP) measured the interactions of TP73-AS1/EZH2 and EZH2/WIF1. Subcutaneous tumor growth was monitored in nude mice and immunohistochemistry (IHC) detected proliferation marker Ki-67 expression.

RESULTS

TP73-AS1 was increased while WIF1 was decreased in EBVaGC cells. Silencing of TP73-AS1 or overexpression of WIF1 repressed the growth and migration while promoted apoptosis of EBVaGC cells. Knockdown of WIF1 reversed the anticancer effect of TP73-AS1 silencing. TP73-AS1 promoted the binding of EZH2 to the WIF1 promoter by directly binding to EZH2, and thus inhibiting the expression of WIF1 by enhancing H3K27me3 level of WIF1 promoter. Moreover, TP73-AS1 activated Wnt/β-catenin signaling pathway and promoted EMT by down-regulating WIF1. TP73-AS1 silencing inhibited the progression of EBVaGC in nude mice by epigenetically regulating WIF1.

CONCLUSION

TP73-AS1 regulated the promoter methylation of WIF1 by recruiting PRC2 complex to WIF1 promoter region, thereby promoting the progression of EBVaGC. These observations provided a novel theoretical basis to investigate more effective therapies of EBVaGC.

miR-193a Directly Targets PSEN1 and Inhibits Gastric Cancer Cell Growth, the Activation of PI3K/Akt Signaling Pathway, and the Epithelial-to-Mesenchymal Transition

Background

Gastric cancer, a kind of gastrointestinal malignancy, is the second type of leading death cancer. miR-193a is a key tumor suppressor in several diseases. PSEN1 is mainly related to Alzheimer's disease and may be involved in the cleavage of the Notch receptor. Material and Methods. RT-PCR and western blot were applied to evaluate miR-193a and the expression level of PSEN1. Luciferase reporter assay was applied to verify whether PSEN1 was a target of miR-193a. The Kaplan–Meier method was employed to calculate the 5-year overall survival of gastric cancer patients.

Results

miR-193a was downregulated in gastric cancer tissues and cell lines, and downregulation of miR-193a predicted poor 5-year overall survival of gastric cancer. miR-193a inhibited the proliferation and the activation of the PI3K/AKT signaling pathway in gastric cancer cells. miR-193a inhibited gastric cancer tumor growth in vivo. miR-193a impaired cell invasion and epithelial-to-mesenchymal transition (EMT) in HGC-27 cells. In addition, PSEN1 was a direct target of miR-193a and PSEN1 reversed partial functions of miR-193a in cell proliferation and invasion.

Conclusion

miR-193a prominently decreased the proliferation, invasion, and activation of the PI3K/Akt signaling pathway and the abilities of epithelial-to-mesenchymal transition in gastric cancer cells. The newly identified miR-193a/PSEN1 axis provides novel insight into the pathogenesis of gastric cancer.

Long Non-Coding RNA LINC00152 Regulates Self-Renewal of Leukemia Stem Cells and Induces Chemo-Resistance in Acute Myeloid Leukemia

Relapse of acute myeloid leukemia (AML) has a very poor prognosis and remains a common cause of treatment failure in patients with this disease. AML relapse is partially driven by the chemoresistant nature of leukemia stem cells (LSCs), which remains poorly understood, and our study aimed at elucidating the underlying mechanism. Accumulating evidences show that long noncoding RNAs (lncRNAs) play a crucial role in AML development. Herein, the lncRNA, LINC00152, was identified to be highly expressed in CD34+ LSCs and found to regulate the self-renewal of LSCs derived from AML patients. Importantly, LINC00152 upregulation was correlated with the expression of 16 genes within a 17-gene LSC biomarker panel, which contributed to the accurate prediction of initial therapy resistance in AML. Knockdown of LINC00152 markedly increased the drug sensitivity of leukemia cells. Furthermore, LINC00152 expression was found to be correlated with poly (ADP-ribose) polymerase 1 (PARP1) expression in AML, whereas LINC00152 knockdown significantly decreased the expression of PARP1. Upregulation of LINC00152 or PARP1 was associated with poor prognosis in AML patients. Collectively, these data highlight the importance and contribution of LINC00152 in the regulation of self-renewal and chemoresistance of LSCs in AML.

LncRNA CYTOR drives L-OHP resistance and facilitates the epithelial-mesenchymal transition of colon carcinoma cells via modulating miR-378a-5p/SERPINE1

Long non-coding RNAs (lncRNAs) play a vital regulatory role in many human cancers. However, their underlying effect and molecular mechanism in chemoresistance need to be fully researched. This study found that lncRNA CYTOR expression was significantly up-regulated in colon carcinoma tissue and cells. Silencing lncRNA CYTOR in vitro facilitated L-OHP sensitivity of colon carcinoma cells and restrained epithelial-mesenchymal transition (EMT). Furthermore, lncRNA CYTOR could inhibit miR-378a-5p expression, while suppressing miR-378a-5p could attenuate the inhibition of lncRNA CYTOR silencing on L-OHP resistance and EMT. The downstream target mRNA of miR-378a-5p was further explored, and it was discovered that miR-378a-5p restrained SERPINE1 expression. Rescue assay indicated that overexpressing miR-378a-5p or silencing SERPINE1 expression counteracted the promotion of lncRNA CYTOR overexpression on L-OHP resistance and EMT of colon carcinoma cells. In vivo experiment exhibited that silencing lncRNA CYTOR repressed colon carcinoma growth, while miR-378a-5p inhibition diminished the suppression of silencing lncRNA CYTOR on colon carcinoma. These results testified that lncRNA CYTOR enhanced L-OHP drug resistance and induced EMT in colon carcinoma. It was also suggested that lncRNA CYTOR/miR-378a-5p/SERPINE1 axis was a regulatory pathway of L-OHP resistance in colon carcinoma. They could be potential therapeutic targets and prognostic biomarkers.Abbreviations: ATG: autophagy related; EPG: ectopic PGL granules; GFP: green fluorescent protein; LGG-1: LC3, GABARAP and GATE-16 family; LPLA-2: lysosomal phospholipase A2; PGL: P granule abnormality protein; PLA2: phospholipase A2; SD: standard deviation; SEPA-1: suppressor of ectopic P granules in autophagy mutant; SQST-1: sequestosome related.

Long noncoding RNAs as diagnostic biomarkers for the early detection of digestive tract cancers: a systematic review and meta-analysis

BACKGROUND

long noncoding RNAs (lncRNAs) have attracted attention recently. However, many inconsistencies frequently appeared for the early diagnosis of digestive tract cancers (DTCs). We performed this meta-analysis to describe the diagnostic performance of lncRNAs in the discrimination of DTCs.

METHODS

data were extracted from PubMed, Web of Science, Embase, and Cochrane Library. Their quality was evaluated using the revised Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Such parameters as sensitivity and specificity were included for pooled analyses. The STATA 12.0 and Meta-Disc 1.4 software packages were used to perform the statistical analysis.

RESULTS

sixty-nine papers were included in this meta-analysis. The pooled analysis of DTCs showed that lncRNAs had a sensitivity of 0.78 and a specificity of 0.80. The area under the summary ROC curve (AUC) was 0.86. For gastric cancer (GC), the pooled sensitivity and specificity were 0.77 (95 % CI: 0.72-0.81) and 0.75 (95 % CI: 0.71-0.79), respectively, and the AUC was 0.83. For colorectal cancer (CRC), these three parameters were 0.82 (95 % CI: 0.76-0.86), 0.84 (95 % CI: 0.79-0.88), and 0.90, respectively. For esophageal cancer (EC) sensitivity was 0.74 (95 % CI: 0.67-0.80) and specificity reached 0.86 (95 % CI: 0.72-0.93), with an AUC of 0.82.

CONCLUSIONS

LncRNAs show potential diagnostic value for discrimination between DTCs.

Capsanthin induces G1/S phase arrest, erlotinib-sensitivity and inhibits tumor progression by suppressing EZH2-mediated epigenetically silencing of p21 in triple-negative breast cancer cells

Capsanthin is a naturally occurring red pepper carotenoid with possible antitumor activity, but its antitumor mechanisms have yet to be delineated. We tested the anti-proliferative activity of capsanthin with human triple-negative breast cancer (TNBC) and found that cell proliferation was inhibited after 24, 48 and 72 h of treatment. We also investigated the cellular and molecular mechanisms of the antitumor efficacy of capsanthin on TNBC cells and found that capsanthin delayed cell-cycle progression at the G1/S stage, that cyclin A expression was suppressed, and that p21 expression was upregulated. Capsanthin also inhibited the EZH2 expression and EZH2 could binding to the p21 promoter in TNBC cells. We further discovered that capsanthin has synthetic effects when combined with erlotinib (Tarceva). In the animal experiment, we found that the capsanthin-induced inhibition of TNBC cell proliferation decreased the incidence of the initiation and growth of TNBC cell–derived tumors in mice. Our study reveals that capsanthin exerted antitumor effects through delaying cell-cycle progression, induces erlotinib-sensitivity and inhibits tumor progression by inhibiting EZH2/p21 axis, and capsanthin is a potential drug candidate for development of a safe and effective therapy against TNBCs, especially for TNBCs that have developed resistance to targeting therapy.

A Positive Feedback Loop of Long Noncoding RNA LINC00152 and KLF5 Facilitates Breast Cancer Growth

The long noncoding RNA (lncRNA) LINC00152, also known as CYTOR, displays aberrant expression in various cancers. However, its clinical value and functional mechanisms in breast cancer remain insufficiently understood. Our study found that LINC00152 is significantly upregulated in breast cancer, and that it acts as an indicator of poor survival prognosis. Further studies revealed that LINC00152 knockdown suppresses cell proliferation and tumorigenicity in vitro and in vivo. Mechanistic analyses demonstrated that LINC00152 directly binds to KLF5 protein and increases KLF5 stability. Moreover, LINC00152 is also a KLF5-responsive lncRNA, and KLF5 activates LINC00152 transcription by directly binding to its promoter. Our study suggests that LINC00152 promotes tumor progression by interacting with KLF5. LINC00152 may be a valuable prognostic predictor for breast cancer, and the positive feedback loop of LINC00152-KLF5 could be a therapeutic target in pharmacological strategies.

LINC00152 mediates CD8+ T-cell infiltration in gastric cancer through binding to EZH2 and regulating the CXCL9, 10/CXCR3 axis

This study aimed to annotate the role of long intergenic non-coding RNA 152 (LINC00152) in CD8⁺ T cells mediated immune responses in gastric cancer (GC) and the underlying mechanism. LINC00152 expression levels were detected through RT-PCR. For tumor engraftment, HGC-27 cells that received LINC00152 shRNA, LINC00152 overexpression vectors, enhancer of zeste homolog 2 (EZH2) shRNA or combination transfection were injected into mice. Chromatin immunoprecipitation (ChIP) assay was used to explore the interaction between LINC00152, Cys-X-cys ligand 9 (CXCL9) and Cys-X-cys ligand 10 (CXCL10). Flow cytometry was adopted to measure the CD8⁺ T-cell infiltration in tumor issue. In this study, we found increased LINC00152 expression levels are positively associated with the poor prognosis of GC patients and negatively associated with the CD8 levels. ChIP assay verified that LINC00152 recruits EZH2 to the promoters of CXCL9 and CXCL10, thus the silencing of LINC00152 promoted the production of CXCL9 and CXCL10. Knockdown of LINC00152 suppressed tumor cells growth in vivo and in vitro, increased tumor-infiltrating CD8⁺ T cells numbers and promoted the expression of CXCL9, CXCL10 and C-X-C Motif Chemokine Receptor 3 (CXCR3) in xenograft tumors. While CD8⁺ T cell depletion reversed the tumor suppression effect of LINC00152 silence. Besides, the silencing of EZH2 partly inhibited the promotion effect LINC00152 on tumor growth. Our study indicated that LINC00152 inhibition suppressed the tumor progress may through promoting CD8⁺ T-cell infiltration.

Molecular determinants and heterogeneity underlying host response to EV-A71 infection at single-cell resolution

The pathogenic human enterovirus EV-A71 has raised serious public health concerns. A hallmark of EV-A71 infection is the distortion of host transcriptomes in favour of viral replication. While high-throughput approaches have been exploited to dissect these gene dysregulations, they do not fully capture molecular perturbations at the single-cell level and in a physiologically relevant context. In this study, we applied a single-cell RNA sequencing approach on infected differentiated enterocyte cells (C2BBe1), which model the gastrointestinal epithelium targeted initially by EV-A71. Our single-cell analysis of EV-A71-infected culture provided several lines of illuminating observations: 1) This systems approach demonstrated extensive cell-to-cell variation in a single culture upon viral infection and delineated transcriptomic differences between the EV-A71-infected and bystander cells. 2) By analysing expression profiles of known EV-A71 receptors and entry facilitation factors, we found that ANXA2 was closely correlated in expression with the viral RNA in the infected population, supporting its role in EV-A71 entry in the enteric cells. 3) We further catalogued dysregulated lncRNAs elicited by EV-A71 infection and demonstrated the functional implication of lncRNA CYTOR in promoting EV-A71 replication. Viewed together, our single-cell transcriptomic analysis illustrated at the single-cell resolution the heterogeneity of host susceptibility to EV-A71 and revealed the involvement of lncRNAs in host antiviral response.

Role of LINC00152 in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancer cases. The pathogenesis of NSCLC involves complex gene networks that include different types of non-coding RNAs, such as long non-coding RNAs (lncRNAs). The role of lncRNAs in NSCLC is gaining an increasing interest as their function is being explored in various human cancers. Recently, a new oncogenic lncRNA, LINC00152 (cytoskeleton regulator RNA (CYTOR)), has been identified in different tumor types. In NSCLC, the high expression of LINC00152 in tumor tissue and peripheral blood samples has been shown to be associated with worse prognoses of NSCLC patients. Overexpression of LINC00152 has been confirmed to promote the proliferation, invasion, and migration of NSCLC cells in vitro, as well as increase tumor growth in vivo. This review discusses the role of LINC00152 in NSCLC.

Long intergenic non-coding RNA Linc00485 promotes lung cancer progression by modulating miR-298/c-Myc axis

Long non‐coding RNAs (lncRNAs), which are non‐protein‐coding transcripts, are emerging as novel biomarkers for cancer diagnosis. Their dysregulation is increasingly recognized to contribute to the development and progression of human cancers, including lung cancer. Linc00485 is a newly discovered cancer‐related lncRNA; however, little is known about its role in lung cancer progression. In this study, we found that the expression of Linc00485 was significantly increased in human lung cancer tissue and associated with malignant phenotypes, including tumour‐node‐metastasis (TNM) stage, metastasis and relapse. Furthermore, the proliferative, migratory and invasive abilities of lung cancer cells in vitro were significantly enhanced by overexpression of Linc00485 but inhibited by its silencing. Mechanistically, Linc00485 regulated the expression of c‐Myc by directly binding to miR‐298; the effects of Linc00485 overexpression could be significantly reversed by a c‐Myc inhibitor or small interfering RNA. Xenotransplantation experiments showed that Linc00485 silencing significantly weakened the proliferation potential of A549 cells in vivo. Overall, these findings indicate that Linc00485 overexpression down‐regulates miR‐298, resulting in the up‐regulation of c‐Myc and thereby promoting the development of lung cancer.

TRIM29 inhibits miR-873-5P biogenesis via CYTOR to upregulate fibronectin 1 and promotes invasion of papillary thyroid cancer cells

Papillary thyroid cancer (PTC) is the most common endocrine tumor with an increasing incidence, has a strong propensity for neck lymph node metastasis. Limited treatment options are available for patients with advanced or recurrent metastatic disease, resulting in a poor prognosis. Tripartite motif protein 29 (TRIM29) is dysregulated in various cancer and functions as oncogene or tumor suppressor in discrete cancers. In this study, we found that both TRIM29 and fibronectin 1 (FN1) were upregulated with positive correlation in PTC tissues. Neither overexpression nor downregulation of TRIM29 altered the proliferation of PTC cells significantly. Overexpression of TRIM29 significantly promotes, while knockdown of TRIM29 significantly decreases migration and invasion by regulating FN1 expression in PTC cells. In terms of mechanism, we found that TRIM29 altered the stability of FN1 mRNA via regulation of miR-873-5p expression. The current study also demonstrated that long non-coding RNA (LncRNA) CYTOR suppressed maturation of miR-873-5p via interaction with premiR-873, and TRIM29 decreased miR-873-5p via upregulation of CYTOR. This study suggests that involvement of TRIM29 in migration and invasion in PTC cells may reveal potential metastatic mechanism of PTC and represent a novel therapeutic target and strategy.

LINC00152 promotes pancreatic cancer cell proliferation, migration and invasion via targeting miR-150

Pancreatic cancer (PC) is one of the top deaths causing cancers with low 5-year survival rate. Long non-coding RNAs (lncRNAs) are recognized as a crucial type of nonprotein-coding transcripts implicated in tumorigenesis. Emerging evidence has implied that LINC00152 exerts the potential oncogenic functions in various cancers. Nevertheless, the role of LINC00152 in PC remains elusive. In the present study, we found that LINC00152 was significantly up-regulated while miR-150 was down-regulated both in tissues and cell lines of PC, indicating their negative correlation in PC progression. Functionally, overexpression of LINC00152 promoted cell proliferation, migration and invasion, while LINC00152 knockdown reversed these effects. Mechanistic experiments reveal that miR-150 acted as a target of LINC00152 confirmed by luciferase reporter assay. Moreover, inhibition of miR-150 could markedly attenuate the suppression of cell proliferation, migration and invasion by knocking down LINC00152. Altogether, our findings concluded that LINC00152 facilitated PC progression through inhibiting miR-150 expression, indicating an innovative therapeutic target for PC.

Promoter Hypomethylation and Increased Expression of the Long Non-coding RNA LINC00152 Support Colorectal Carcinogenesis

Up-regulation of the long non-coding RNA LINC00152 can contribute to cancer development, proliferation and invasion, including colorectal cancer, however, its mechanism of action in colorectal carcinogenesis and progression is only insufficiently understood. In this work we correlated LINC00152 expression with promoter DNA methylation changes in colorectal tissues along the normal-adenoma-carcinoma sequence and studied the effects of LINC00152 silencing on the cell cycle regulation and on the whole transcriptome in colon carcinoma cells using cell and molecular biology techniques. LINC00152 was significantly up-regulated in adenoma and colorectal cancer (p < 0.001) compared to normal samples, which was confirmed by real-time PCR and in situ hybridization. LINC00152 promoter hypomethylation detected in colorectal cancer (p < 0.01) was strongly correlated with increased LINC00152 expression (r=-0.90). Silencing of LINC00152 significantly suppressed cell growth, induced apoptosis and decreased cyclin D1 expression (p < 0.05). Whole transcriptome analysis of LINC00152-silenced cells revealed significant down-regulation of oncogenic and metastasis promoting genes (e.g. YES proto-oncogene 1, PORCN porcupine O-acyltransferase), and up-regulation of tumour suppressor genes (e.g. DKK1 dickkopf WNT signalling pathway inhibitor 1, PERP p53 apoptosis effector) (adjusted p < 0.05). Pathway analysis confirmed the LINC00152-related activation of oncogenic molecular pathways including those driven by PI3K/Akt, Ras, WNT, TP53, Notch and ErbB. Our results suggest that promoter hypomethylation related overexpression of LINC00152 can contribute to the pathogenesis of colorectal cancer by facilitating cell progression through the up-regulation of several oncogenic and metastasis promoting pathway elements.

Transcriptome Analysis Identifies LINC00152 as a Biomarker of Early Relapse and Mortality in Acute Lymphoblastic Leukemia

Evidence showing the role of long non-coding RNAs (lncRNAs) in leukemogenesis have emerged in the last decade. It has been proposed that these genes can be used as diagnosis and/or prognosis biomarkers in childhood acute lymphoblastic leukemia (ALL). To know if lncRNAs are associated with early relapse and early mortality, a microarray-based gene expression analysis in children with B-lineage ALL (B-ALL) was conducted. Cox regression analyses were performed. Hazard ratios (HR) and 95% confidence intervals (95% CI) were calculated. LINC00152 and LINC01013 were among the most differentially expressed genes in patients with early relapse and early mortality. For LINC00152 high expression, the risks of relapse and death were HR: 4.16 (95% CI: 1.46–11.86) and HR: 1.99 (95% CI: 0.66–6.02), respectively; for LINC01013 low expression, the risks of relapse and death were HR: 3.03 (95% CI: 1.14–8.05) and HR: 6.87 (95% CI: 1.50–31.48), respectively. These results were adjusted by NCI risk criteria and chemotherapy regimen. The lncRNA–mRNA co-expression analysis showed that LINC00152 potentially regulates genes involved in cell substrate adhesion and peptidyl–tyrosine autophosphorylation biological processes. The results of the present study point out that LINC00152 could be a potential biomarker of relapse in children with B-ALL.

Down-regulation of lncRNA LINC00152 Suppresses Gastric Cancer Cell Migration and Invasion Through Inhibition of the ERK/MAPK Signaling Pathway

Purpose

The aim of this study was to explore the regulatory role and mechanism of long noncoding RNA LINC00152 in gastric cancer (GC) cells.

Methods

LINC00152 expression in GC tissues and cells was detected by reverse transcription-polymerase chain reaction (qRT-PCR). MKN45 and MGC-803 cells were selected and assigned into different groups after transfection with si-LINC00152, activated ERK/MAPK signaling pathway (SA), or negative control. Cell proliferation, apoptosis, cycle, migration and invasion were assessed by CCK-8, flow cytometry, Transwell assay and Scratch test, respectively. Western blot analysis was conducted to detect the expression of E-cadherin, N-cadherin and ERK/MAPK signaling pathway protein.

Results

Compared with the normal tissues, higher expression of LINC00152 was found in GC tissues and LINC00152 was remarkably correlative with clinical stage and lymphatic metastasis. LINC00152 expression in GC cells was higher than that in GES-1 cells. Compared with the NC group, the cell proliferation rate, cells in G2/M phase, migration and invasion abilities as well as the expression of N-cadherin and p-ERK-1/2 were significantly decreased, and the expression of E-cadherin, cells in G0/G1 phase and cell apoptosis rate were significantly increased in the si-LINC00152-1 group. ERK/MAPK signaling pathway activator SA could reverse the biological role of LINC00152 in GC cells.

Conclusion

These results demonstrated that the interference of LINC00152 expression may inhibit the invasion and migration of GC cells by inhibiting the ERK/MAPK signaling pathway.

Carcinogenic roles and therapeutic effects of EZH2 in gynecological cancers

Enhancer of Zeste Homolog 2 (EZH2) is highly expressed in kinds of malignant tumors and related to tumor occurrence, development, and prognosis. EZH2 is the catalytic subunit of the polycomb repressive complex 2 (PRC2), which promotes cell proliferation, migration, and invasion by epigenetic regulation of anti-tumor gene. It can activate numerous tumor-associated signaling pathways and interfere with DNA damage repair. In recent years, large amounts of studies have shown that EZH2 is closely related to gynecologic-related malignancies and can be used as a potential target gene for the treatment of gynecological-related malignancies. This review summarizes the oncogenic function of EZH2 and introduces the recent advances in the development of EZH2 inhibitors. On this basis, future research prospect of EZH2 is proposed.

Master and servant: LINC00152 - a STAT3-induced long noncoding RNA regulates STAT3 in a positive feedback in human multiple myeloma

Background

The survival of INA-6 human multiple myeloma cells is strictly dependent upon the Interleukin-6-activated transcription factor STAT3. Although transcriptional analyses have revealed many genes regulated by STAT3, to date no protein-coding STAT3 target gene is known to mediate survival in INA-6 cells. Therefore, the aim here was to identify and analyze non-protein-coding STAT3 target genes. In addition to the oncogenic microRNA-21, we previously described five long noncoding RNAs (lncRNAs) induced by STAT3, named STAiRs. Here, we focus on STAT3-induced RNA 18 (STAiR18), an mRNA-like, long ncRNA that is duplicated in the human lineage. One STAiR18 locus is annotated as the already well described LINC00152/CYTOR, however, the other harbors the MIR4435-2HG gene and is, up to now, barely described.

Methods

CAPTURE-RNA-sequencing was used to analyze STAiR18 transcript architecture. To identify the STAiR18 and STAT3 phenotype, siRNA-based knockdowns were performed and microarrays were applied to identify their target genes. RNA-binding partners of STAiR18 were determined by Chromatin-Isolation-by-RNA-Purification (ChIRP) and subsequent sequencing. STAT3 expression in dependence of STAiR18 was investigated by immunoblots, chromatin- and RNA-immunoprecipitations.

Results

As identified by CAPTURE-RNA sequencing, a complex splice pattern originates from both STAiR18 loci, generating different transcripts. Knockdown of the most abundant STAiR18 isoforms dramatically decreased INA-6 cell vitality, suggesting a functional role in myeloma cells. Additionally, STAiR18 and STAT3 knockdowns yielded overlapping changes of transcription patterns in INA-6 cells, suggesting a close functional interplay between the two factors. Moreover, Chromatin isolation by RNA purification (ChIRP), followed by genome-wide RNA sequencing showed that STAiR18 associates specifically with the STAT3 primary transcript. Furthermore, the knockdown of STAiR18 reduced STAT3 levels on both the RNA and protein levels, suggesting a positive feedback between both molecules. Furthermore, STAiR18 knockdown changes the histone methylation status of the STAT3 locus, which explains the positive feedback and indicates that STAiR18 is an epigenetic modulator.

Conclusion

Hence, STAiR18 is an important regulator of myeloma cell survival and is strongly associated with the oncogenic function of STAT3. The close functional interplay between STAT3 and STAiR18 suggests a novel principle of regulatory interactions between long ncRNAs and signaling pathways.

Prognostic Values of Long Noncoding RNA linc00152 in Various Carcinomas: An Updated Systematic Review and Meta-Analysis

Dysregulation of the long noncoding RNA linc00152 has been reported in various solid tumors. Here, we performed a synthetic analysis to clarify the clinical value of linc00152 as a prognostic indicator in malignant tumors. Article collection was conducted using several electronic databases, including PubMed, Web of Science, Medline, OVID, and Embase (up to February 13, 2018). The meta-analysis comprised nine original studies and 808 total patients. The application of a random-effects model revealed significant positive association between high expression level of linc00152 and lymph node metastasis (odds ratio [OR] = 2.93, 95% confidence interval [CI]: 1.88-4.57, p < .0001; I2  = 48.8, p = .119) and negative association with low-grade cancer (OR = 2.43, 95% CI: 1.51-3.92; I2  = 61.7, p = .033), while with tumor recurrence (hazard ratio [HR] = 3.32, 95% CI: 1.98-5.57, p < .0001; I2  = 0, p = .451) by fixed-effects model as the low heterogeneity. As demonstrated via the application of the fixed-effects model, Linc00152 overexpression is positively related to poor overall survival (pooled HR = 1.98, 95% CI: 1.70-2.31, p < .0001; I2  = 0%, p = .756) and poor disease-free survival (HR = 1.66, 95% CI: 1.20-2.29, p < .0001; I2  = 75.8%, p = .042) in human solid cancers. Statistically significant associations were additionally found with cancer type, sample size, and follow-up time. In conclusion, linc00152 is of potential value as a novel biomarker of lymph node metastasis and prognosis in human cancer. IMPLICATIONS FOR PRACTICE: linc00152 is of potential value as a novel biomarker of lymph node metastasis and prognosis in human cancer.

Long non-coding RNA signature in gastric cancer

Gastric cancer as a common human malignancy has been associated with aberrant expressions of several coding and non-coding genes. Long non-coding RNAs (lncRNAs) as regulators of gene expressions at different genomic, transcriptomic and post-transcriptomic levels are among putative biomarkers and therapeutic targets in gastric cancer. In the present study, we have searched available literature and listed lncRNAs that are involved in the pathogenesis of gastric cancer. In addition, we discuss associations between expressions of these lncRNAs and tumoral features or risk factors for gastric cancer. Based on the established role of lncRNAs in regulation of genomic stability, cell cycle, apoptosis, angiogenesis and other aspects of cell physiology, the potential of these transcripts as therapeutic targets in gastric cancer should be evaluated in future studies.

Targeting Long Non-Coding RNAs in Nervous System Cancers: New Insights in Prognosis, Diagnosis and Therapy

Long non-coding RNAs (lncRNAs) constitute one of the most broad and diverse classes of cellular transcripts, playing key roles as regulatory molecules in many biological processes. Although the biology of lncRNAs is a new and emerging field of research, several studies have already shown that alterations in the expression of lncRNAs are associated with the development and progression of cancer in different organs and tissues, including central and peripheral nervous system. In this review, we summarize the oncogenic and tumor suppressive roles of lncRNAs in malignant tumors of the nervous system, such as glioma and neuroblastoma, focusing on their functional interactions with DNA, other RNA and protein molecules. We further discuss the potential use of lncRNAs as biomarkers for diagnosis, prognosis and tumor treatment. Gaining insight into the functional association between nervous system malignancies and lncRNAs could offer new perspectives to the development of promising therapeutic tools against cancer.

Long non-coding RNA linc00152 acting as a promising oncogene in cancer progression

The incidence and mortality rate of cancer continues to gradually increase, although considerable research effort has been directed at elucidating the molecular mechanisms underlying biomarkers responsible for tumorigenesis. Accumulated evidence indicates that the long non-coding RNAs (lncRNAs), which are transcribed but not translated into functional proteins, contribute to cancer development. Recently, linc00152 (an lncRNA) was identified as a potent oncogene in various cancer types, and shown to be involved in cancer cell proliferation, invasiveness, and motility by sponging tumor-suppressive microRNAs acting as a competing endogenous RNA, binding to gene promoters acting as a transcriptional regulator, and binding to functional proteins. In this review, we focus on the oncogenic role of linc00152 in tumorigenesis and provided an overview of recent clinical studies on the effects of linc00152 expression in human cancers.

LncRNAs as potential diagnostic and prognostic biomarkers in gastric cancer: A novel approach to personalized medicine

Gastric cancer is the third leading cause of cancer death with 5-year survival rate of about 30-35%. Since early detection is associated with decreased mortality, identification of novel biomarkers for early diagnosis and proper management of patients with the best response to therapy is urgently needed. Long noncoding RNAs (lncRNAs) due to their high specificity, easy accessibility in a noninvasive manner, as well as their aberrant expression under different pathological and physiological conditions, have received a great attention as potential diagnostic, prognostic, or predictive biomarkers. They may also serve as targets for treating gastric cancer. In this review, we highlighted the role of lncRNAs as tumor suppressors or oncogenes that make them potential biomarkers for the diagnosis and prognosis of gastric cancer. Relatively, lncRNAs such as H19, HOTAIR, UCA1, PVT1, tissue differentiation-inducing nonprotein coding, and LINC00152 could be potential diagnostic and prognostic markers in patients with gastric cancer. Also, the impact of lncRNAs such as ecCEBPA, MLK7-AS1, TUG1, HOXA11-AS, GAPLINC, LEIGC, multidrug resistance-related and upregulated lncRNA, PVT1 on gastric cancer epigenetic and drug resistance as well as their potential as therapeutic targets for personalized medicine was discussed.

Overexpression LINC01082 suppresses the proliferation, migration and invasion of colon cancer

Long non-coding RNAs (lncRNAs) are emerging as pivotal regulators in human cancer. LINC01082 was expressed as decreased in colon cancer by previous lncRNA-seq result and TCGA database, however, the role and function of LINC0182 is not clear in colon cancer. Here, we aimed to explore the role of LINC01082 in colon cancer for exploring the etiopathogenesis of colon cancer. RT-qPCR for LINC01082 expression in tissues (colon cancer vs. their matched adjacent non-cancerous tissues, ANT, n = 39) and cells (colon cancer cells vs. normal colon cells, n = 4) were performed. CCK-8 assay for proliferation of colon cancer, Transwell assay for migration and invasion were carried out in sw480 and sw620 cells. The results revealed that LINC01082 was significantly decreased in tissues and cell lines of colon cancer. Overexpressed LINC01082 significantly suppressed the proliferation ability of colon cancer cells. The migration and invasion of colon cancer cells were also suppressed after LINC01082 overexpression. These findings demonstrated that LINC01082 may act in suppressing the incidence and development of colon cancer via suppressing cell proliferation, migration and invasion, indicating that LINC01082 may act as a new tumor suppressor and may be a promising therapy target for colon cancer.

Improved characterization of the relationship between long intergenic non-coding RNA Linc00152 and the occurrence and development of malignancies

Linc00152, located on chromosome 2p11.2, is a long intergenic non-coding RNA molecule with 828 nucleotides that is highly expressed in many types of human tumor tissues, especially in malignant tumors of the digestive system. Linc00152 promotes the occurrence and development of tumors by increasing tumor cell proliferation, invasion, metastasis, and apoptosis. Additionally, linc00152 contributes to the carcinogenesis of several cancers, including gastric cancer, liver cancer, hepatocellular carcinoma, gallbladder cancer, clear cell renal cell carcinoma, and colorectal cancer, by disturbing various signaling pathways (eg PI3K/AKT, mTOR, IL-1, and NOTCH 1 signaling pathways). High linc00152 expression levels are associated with chemoresistance as well as poor prognosis and shorter survival. Continual advances made in the relevant research have indicated that linc00152 may be useful as a new tumor molecular biomarker, applicable for tumor diagnosis, targeted therapy, and prognosis assessment. This review summarizes the progress in the research into the relationship between linc00152 and the occurrence and development of malignancies based on molecular functions, regulatory mechanisms, and clinical applications.

Upregulation of long noncoding RNA LINC00152 promotes proliferation and metastasis of esophageal squamous cell carcinoma

Purpose: Esophageal cancer is a major cause of cancer-related mortality worldwide. The long noncoding RNA LINC00152 has been confirmed to play an oncogenic role in many cancers. However, the expression pattern and function of LINC00152 in human esophageal squamous cell carcinoma (ESCC) remain unclear.

Materials and methods: We evaluated LINC00152 expression in ESCC by qPCR and in situ hybridization. Proliferation, apoptosis, cell cycle, migration and invasion were examined in ESCC cells knocked down for LINC00152 knockdown by siRNA. Furthermore, an mRNA microarray was performed in ESCC cells with LINC00152 knockdown.

Results: LINC00152 was significantly upregulated in human ESCC clinical samples (P<0.001) and cell lines (P=0.008), and LINC00152 overexpression was related to lymphatic metastasis (P=0.03) and advanced pTNM classification (P=0.005). Furthermore, ESCC patients with LINC00152 overexpression had significantly shorter overall survival (P=0.007), and LINC00152 overexpression was an independent risk factor for overall survival of ESCC patients. LINC00152 knockdown inhibited the proliferation, migration and invasion of ESCC cells in vitro. In addition, mechanistic investigations through mRNA array and immunoblot analyses demonstrated that LINC00152 regulated the expression of several cell cycle-related proteins and SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) interactions in vesicular transport pathway proteins.

Conclusion: Our research indicated that LINC00152 exhibits oncogenic functions in ESCC and may represent a potential new target for ESCC therapy.

LncRNAs with miRNAs in regulation of gastric, liver, and colorectal cancers: updates in recent years

Long noncoding RNA (lncRNA) is a kind of RNAi molecule composed of hundreds to thousands of nucleotides. There are several major types of functional lncRNAs which participate in some important cellular pathways. LncRNA-RNA interaction controls mRNA translation and degradation or serves as a microRNA (miRNA) sponge for silencing. LncRNA-protein interaction regulates protein activity in transcriptional activation and silencing. LncRNA guide, decoy, and scaffold regulate transcription regulators of enhancer or repressor region of the coding genes for alteration of expression. LncRNA plays a role in cellular responses including the following activities: regulation of chromatin structural modification and gene expression for epigenetic and cell function control, promotion of hematopoiesis and maturation of immunity, cell programming in stem cell and somatic cell development, modulation of pathogen infection, switching glycolysis and lipid metabolism, and initiation of autoimmune diseases. LncRNA, together with miRNA, are considered the critical elements in cancer development. It has been demonstrated that tumorigenesis could be driven by homeostatic imbalance of lncRNA/miRNA/cancer regulatory factors resulting in biochemical and physiological alterations inside the cells. Cancer-driven lncRNAs with other cellular RNAs, epigenetic modulators, or protein effectors may change gene expression level and affect the viability, immortality, and motility of the cells that facilitate cancer cell cycle rearrangement, angiogenesis, proliferation, and metastasis. Molecular medicine will be the future trend for development. LncRNA/miRNA could be one of the potential candidates in this category. Continuous studies in lncRNA functional discrepancy between cancer cells and normal cells and regional and rational genetic differences of lncRNA profiles are critical for clinical research which is beneficial for clinical practice.

Higher Expression of Linc00152 Promotes Bladder Cancer Proliferation and Metastasis by Activating the Wnt/β-Catenin Signaling Pathway

BACKGROUND Recent studies have demonstrated that Linc00152 is highly expressed in multiple cancer types and its genes show tumor-promoting characteristics. However, the efficacy and biological mechanism of Linc00152 in bladder cancer remains unclear. MATERIAL AND METHODS We study investigated the relative expression and promoter methylation of Linc00152 in 126 cases of bladder cancer tissues by qRT-PCR and Bisulfite sequencing PCR. qRT-PCR was used to assess the relative expression of Linc00152 in 4 human bladder cancer cell lines. To explore the biological properties of Linc00152, we performed cell growth and soft-agar colony-formation assays, flow cytometry analyses, wound-healing assay, and Transwell assay. Western blot analysis was used to detect the underlying mechanisms of Linc00152 in bladder cancer. RESULTS We found that Linc00152 was highly expressed in 126 cases of bladder carcinoma tissues (p<0.001) and 4 cell lines (p<0.01), and Linc00152 is more commonly expressed in patients with advanced-stage cancer (p=0.021). Knockdown of Linc00152 by using siRNAs in bladder cancer cell lines (T24 and HT-1197) suppressed cell viability and growth by causing cell cycle arrest and apoptosis (p<0.001), as well as inhibiting cell migration and invasion (p<0.001). In addition, the quantitative RT-PCR and Western blot results suggest that knockdown of Linc00152 reduced Wnt/ß-Catenin signaling (p<0.001). CONCLUSIONS This research shows that Linc00152 is highly expressed in patients with bladder cancer and the possible carcinogenic effect of Linc00152 in bladder cancer occurs through activating the Wnt/ß-Catenin signaling pathway, and could be a new biomarker for diagnosis and prevention of this cancer.

Long non‑coding RNA UCA1 confers tamoxifen resistance in breast cancer endocrinotherapy through regulation of the EZH2/p21 axis and the PI3K/AKT signaling pathway

Tamoxifen is the gold standard for breast cancer endocrinotherapy. However, drug resistance remains a major limiting factor of tamoxifen treatment. Long non‑coding (lnc) RNA serves an important role in drug resistance; however, the molecular mechanisms of tamoxifen resistance in breast cancer endocrinotherapy are largely unclear. lncRNA urothelial cancer associated 1 (lncRNA UCA1, UCA1) has been proven to be dysregulated in human breast cancer and promotes cancer progression. In the present study, it was demonstrated that UCA1 was significantly upregulated in breast cancer tissues compared with healthy tissues. Furthermore, the expression level of UCA1 was significantly greater in tamoxifen‑resistant breast cancer cells (LCC2 and LCC9) when compared with those in the tamoxifen‑sensitive breast cancer cells (MCF‑7 and T47D). UCA1 silencing in LLC2 and LLC9 cells increased tamoxifen drug sensitivity by promoting cell apoptosis and arresting the cell cycle at the G2/M phase. Notably, the induced overexpression of UCA1 in MCF‑7 and T47D cells decreased the drug sensitivity of tamoxifen. The molecular mechanism involved in UCA1‑induced tamoxifen‑resistance was also investigated. It was identified that UCA1 was physically associated with the enhancer of zeste homolog 2 (EZH2), which suppressed the expression of p21 through histone methylation (H3K27me3) on the p21 promoter. In addition, it was demonstrated that UCA1 expression was paralleled to the phosphorylation of CAMP responsive element binding protein (CREB) and AKT. When LCC2 cells were treated with the phosphoinositide 3‑kinase (PI3K)/protein kinase B (AKT) signaling pathway inhibitor LY294002, the phosphorylation levels of CREB and AKT were significantly downregulated. Taken together, it was concluded that UCA1 regulates the EZH2/p21 axis and the PI3K/AKT signaling pathway in breast cancer, and may be a potential therapeutic target for solving tamoxifen resistance.

[Knocking down fascin inhibits cervical cancer cell proliferation and tumorigenesis in nude mice]

OBJECTIVE

To study the effect of knocking down fascin on cervical cancer cell proliferation and tumorigenicity in nude mice.

METHODS

Cervical cancer CaSki cells were infected with a lentiviral vector carrying fascin siRNA or with a negative control lentivirus, and fascin mRNA and protein expressions in the cells were detected using qRT-PCR and Western blotting. MTT assay was used to determine the proliferation of CaSki cells with fascin knockdown. CaSki cells transfected with fascin siRNA or the control lentiviral vector and non-transfected CaSki cells were inoculated subcutaneously in nude mice, and the volume and weight of the transplanted tumor were measured; Western blotting was used to detect the expressions of proliferating cell nuclear antigen (PCNA), survivin, cyclin dependent kinase 4 (CDK4) and p21 proteins in the tumor xenograft.

RESULTS

Infection with the lentiviral vector carrying fascin siRNA, but not the negative control vector, caused significant reductions in the expression levels of fascin mRNA and protein in CaSki cells (P &lt; 0.05). Fascin knockdown resulted in significantly reduced proliferation of CaSki cells in vitro (P &lt; 0.05). The nude mice inoculated with CaSki cells with fascin knockdown showed reduced tumor volume and weight, lowered levels of PCNA, survivin and CDK4, and increased expression of p21 protein in the tumor xenograft compared with the control mice. The negative control lentivirus did not affect the proliferation or tumorigenicity of CaSki cells in nude mice or the expression levels of PCNA, survivin, CDK4 or p21 proteins in the xenografts.

CONCLUSIONS

Knocking down fascin can inhibit the growth and tumorigenicity of cervical cancer cells in nude mice.

LINC00152 facilitates tumorigenesis in esophageal squamous cell carcinoma via miR-153-3p/FYN axis

Long non-coding RNAs (LncRNAs) have been found to be associated with the biological behaviors of human cancers. LINC00152 is reported as an oncogene in many kinds of malignancies. However, the functions and mechanisms of LINC00152 involved in esophageal squamous cell carcinoma (ESCC) remain elusive. Our results revealed that LINC00152 expression was up-regulated in ESCC, and correlated with advanced TNM stage, lymph node metastasis, and poor prognosis of ESCC patients. Functionally, LINC00152 knockdown suppressed proliferation, decreased colony forming ability, and induced apoptosis in ESCC cells. Mechanically, LINC00152 functioned as a competing endogenous RNA (ceRNA) to sponge miR-153-3p, thereby facilitating its downstream target FYN. Moreover, miR-153-3p-mediated tumor-suppressive effects were partly reversed following LINC00152 overexpression. Also, FYN knockdown displayed a similar anti-cancerous role in ESCC cells. Taken together, LINC00152 contributed to ESCC progression by down-regulating miR-153-3p and promoting FYN expression, uncovering a novel LINC00152/miR-153-3p/FYN regulatory pathway in ESCC.