EZH2-mediated epigenetic suppression of long noncoding RNA SPRY4-IT1 promotes NSCLC cell proliferation and metastasis by affecting the epithelial-mesenchymal transition

Deregulation of long noncoding RNAs ANCR, TINCR, HOTTIP and SPRY4-IT1 in plasma of systemic sclerosis patients: SPRY4-IT1 as a novel biomarker of scleroderma and its subtypes

Systemic sclerosis or systemic scleroderma (SSc) is an inflammatory autoimmune disease whose pathogenesis remains ambiguous; however, epigenetics, including long noncoding RNAs (lncRNAs) is an emerging paradigm. To date, the expression, role and clinical significance of most lncRNAs in SSc remain unelucidated. Herein, we investigated the plasma expression profiles of lncRNAs; ANCR, TINCR, HOTTIP, and SPRY4-IT1, which were linked to skin biology, in SSc patients and its subtypes, their potential as diagnostic tools and their correlations with autoantibodies and disease manifestations. Sixty-three SSc patients and thirty-five healthy volunteers were recruited. Autoantibody profile (anti-Scl-70, anti-centromere, anti-RNA polymeraseIII, anti-ribonucleoprotein, antinuclear, and anti-phospholipid antibodies) was determined. lncRNAs analysis was conducted using RT-qPCR. Plasma TINCR, HOTTIP, and SPRY4-IT1 upregulation and ANCR downregulation were observed in SSc patients compared with controls. SPRY4-IT1 was superior in SSc diagnosis in ROC analysis and predicted its risk in multivariate logistic analysis. Plasma SPRT4-IT1 was higher in diffuse than limited SSc. SPRY4-IT1 and HOTTIP were positively correlated with modified Rodnan skin score while ANCR showed a negative correlation only in limited SSc. ANCR and TINCR were positively correlated with disease duration and ESR, respectively. ANCR and SPRY4-IT1 were positively correlated with pulmonary hypertension. HOTTIP was positively correlated with antinuclear antibody. SPRY4-IT1 was positively correlated with HOTTIP in the whole group, and with TINCR only in diffuse SSc. We introduce plasma SPRY4-IT1, HOTTIP, ANCR and TINCR as novel candidate biomarkers for SSc, with SPRY4-IT1 could predict SSc diagnosis and discriminate its subtypes. Our findings widen the epigenetic landscape of SSc and provide surrogates for future predictive studies.

LINC00210 plays oncogenic roles in non-small cell lung cancer by sponging microRNA-328-5p

Long noncoding RNA (lncRNA) has an important role in regulating non-small cell lung cancer (NSCLC) progression. The present study aimed to investigate the effect of LINC00210 in NSCLC progression in order to provide a novel treatment target for patients with NSCLC. A total of 39 NSCLC patients were obtained and divided into LINC00210 high expression and low expression groups. Subsequently, the 5-year survival rate from this patient cohort was analyzed. The SK-MES-1 and A549 NSCLC and the human 16-HBE bronchial epithelial cell lines were utilized to investigate expression level of LIN00210. A549 cells were used to investigate cell proliferation, migration and invasive abilities using Cell Counting kit 8, Transwell and Matrigel assays, respectively. In addition, the luciferase reporter gene assay was performed to investigate the potential target of LINC00210. Reverse transcription-quantitative PCR was used to determine LINC00210 and microRNA (miR)-328-5p expression levels in NSCLC tissues and tumor cell lines (SK-MES-1 and A549). The results demonstrated that LINC00210 was upregulated in NSCLC tissues and cell lines compared with that in normal tissues and 16-HBE cells, and that LINC00210 expression was associated with a poor prognosis in patients with NSCLC (P<0.05). Furthermore, A549 cell transfection with small interfering (si)LINC00210#1 and siLINC00210#2 induced a significant decrease in cell proliferation, and migratory and invasive abilities compared with that in the control groups (P<0.05). In addition, miR-328-5p overexpression was stimulated by knockdown of LINC00210. Furthermore, A549 cells transfected with siLINC00210#1 and miR-328-5p inhibitor exhibited a significant increase in cell proliferation, and migratory and invasive ability compared with that in A549 cells transfected with siLINC00210#1. These findings suggest that LINC00210 may serve as an oncogenic role in NSCLC by sponging miR-328-5p.

SPRY4 regulates trophoblast proliferation and apoptosis via regulating IFN-γ-induced STAT1 expression and activation in recurrent miscarriage

PROBLEM

The dysregulation of trophoblast functions is one of the leading causes of recurrent miscarriage (RM), which frustrates 1%-5% of couples of childbearing ages. Sprouty 4 (SPRY4) is considered as a tumour suppressor and exerts a negative role in cell viability. However, its role in regulating trophoblast behaviors at the maternal-fetal interface remains largely unknown.

METHOD OF STUDY

First-trimester villous samples were collected from RM patients and healthy controls (HCs) to determine the SPRY4 expression in human placenta during early pregnancy. The HTR8/SVneo cell line was introduced to clarify trophoblast cell functions via transfecting with specific short interfering RNA against SPRY4 or SPRY4-overexpressing lentivirus in vitro. In addition, gene expression microarray analysis was performed to explore the downstream molecules and pathways.

RESULTS

Our results revealed that SPRY4 expression was significantly increased in the first-trimester cytotrophoblasts of RM patients compared with HCs. Furthermore, SPRY4 overexpression inhibited trophoblast proliferation and accelerated apoptosis in vitro, while SPRY4 knockdown reversed these effects. Mechanistically, IFN-γ -induced STAT1 expression and activation were involved in the regulation of trophoblast proliferation and apoptosis by SPRY4, and IFN-γ promoted SPRY4 expression and STAT1 phosphorylation through PI3K/AKT pathway. Additionally, both STAT1 and phosphorylated STAT (p-STAT) levels were also upregulated in trophoblasts from RM patients and positively correlated with SPRY4 expression.

CONCLUSION

Our findings indicate that SPRY4 may act as a negative regulator of trophoblast functions through upregulating IFN-γ/PI3K/AKT-induced STAT1 activation. High levels of SPRY4 and STAT1 may contribute to RM development and progression, and blocking of either target could be a novel therapeutic strategy for RM patients.

Long Non-Coding RNA SPRY4-IT1 Reverses Cisplatin Resistance by Downregulating MPZL-1 via Suppressing EMT in NSCLC

Purpose

Long non-coding RNA (lncRNA) SPRY4 intronic transcript 1 (SPRY4-IT1) is reported to play important roles in the occurrence and development of many tumors. However, the possible role of SPRY4-IT1 in cisplatin (DDP) resistance of non-small-cell lung cancer (NSCLC) remains unclear. The aim of this study is to investigate the functions and molecular mechanisms underlying SPRY4-IT1 of cisplatin resistance in NSCLC.

Methods

Expression of SPRY4-IT1 was analyzed in A549 and cisplatin-resistant A549/DDP cell lines by quantitative real-time polymerase chain reaction (RT-qPCR). Overexpression techniques were applied to investigate the biological functions of SPRY4-IT1 in cisplatin-resistant A549/DDP cells. The effects of SPRY4-IT1 on proliferation and apoptosis were evaluated using cell counting kit-8 (CCK8) assays, colony formation assay and flow-cytometric analysis. The expressions of epithelial–mesenchymal transition (EMT)-associated proteins, including E-cadherin and Vimentin, were detected by Western blot. Microarray analysis was performed to identify the putative targets of SPRY4-IT1, which were further verified by Western blotting and RT-qPCR. A549/DDP cells transfected with pCDNA-SPRY4-IT1 were injected into nude mice in order to verify the effect of SPRY4-IT1 on cisplatin resistance in vivo.

Results

The present study demonstrated that SPRY4-IT1 expression was decreased in A549/DDP cells compared with parental A549 cells. Upregulation of SPRY4-IT1 suppressed cell proliferation and caused apoptosis of A549/DDP cells both in vitro and in vivo. MPZL-1 was negatively regulated by SPRY4-IT1. Furthermore, upregulation of SPRY4-IT1 and downregulation of MPZL-1 could suppress epithelial–mesenchymal transition (EMT), which was characterized by increased E-cadherin expression and decreased Vimentin expression.

Conclusion

Upregulation of SPRY4-IT1 reversed the cisplatin-resistant phenotype of NSCLC partially by downregulating MPZL-1 via inhibiting EMT process.

Exosome-transmitted lncRNA UFC1 promotes non-small-cell lung cancer progression by EZH2-mediated epigenetic silencing of PTEN expression

Long non-coding RNAs (LncRNAs) have been suggested as important regulators of cancer development and progression in non-small cell lung cancer (NSCLC). Nevertheless, the biological roles and clinical significance of lncRNA UFC1 in NSCLC remain unclear. We detected the expression of UFC1 in tumor tissues, serum, and serum exosomes of NSCLC patients by qRT-PCR. Gene overexpression or silencing were used to examine the biological roles of UFC1 in NSCLC. RNA immunoprecipitation and ChIP assays were performed to evaluate the interaction between UFC1 and enhancer of zeste homolog 2 (EZH2) and the binding of EZH2 to PTEN gene promoter. Rescue study was used to access the importance of PTEN regulation by UFC1 in NSCLC progression. UFC1 expression was upregulated in tumor tissues, serum, and serum exosomes of NSCLC patients and high level of UFC1 was associated with tumor infiltration. UFC1 knockdown inhibited NSCLC cell proliferation, migration and invasion while promoted cell cycle arrest and apoptosis. UFC1 overexpression led to the opposite effects. Mechanistically, UFC1 bound to EZH2 and mediated its accumulation at the promoter region of PTEN gene, resulting in the trimethylation of H3K27 and the inhibition of PTEN expression. UFC1 knockdown inhibited NSCLC growth in mouse xenograft tumor models while the simultaneous depletion of PTEN reversed this effect. NSCLC cells derived exosomes could promote NSCLC cell proliferation, migration and invasion through the transfer of UFC1. Moreover, Exosome-transmitted UFC1 promotes NSCLC progression by inhibiting PTEN expression via EZH2-mediated epigenetic silencing. Exosome-mediated transmit of UFC1 may represent a new mechanism for NSCLC progression and provide a potential marker for NSCLC diagnosis.

LincRNA00494 Suppresses Non-small Cell Lung Cancer Cell Proliferation by Regulating SRCIN1 Expression as a ceRNA

Background: Lung cancer is the most common malignant tumor worldwide. Accumulating results have shown that long non-coding RNAs (lncRNAs) play a key role in tumorigenesis. Patients and Methods: A total of 163 tumor tissues were collected from non-small cell lung cancer (NSCLC) patients from West China Hospital of Sichuan University. LincRNA00494 is a novel lncRNA, and its expression and biological effect in NSCLC were reported in this study. NSCLC cell lines were used in this study. Results: LincRNA00494 is mainly distributed in the cytoplasm. LincRNA00494 was downregulated in the tumor tissues compared with the adjacent non-tumor tissues. LincRNA00494 expression was positively correlated with SRCIN1 expression (R = 0.57, P < 0.05). Silencing of LincRNA00494 in the cell lines substantially decreased SRCIN1 expression at the mRNA and protein levels, whereas overexpression of LincRNA00494 enhanced the SRCIN1 levels. miR-150-3p significantly decreased the luciferase signals of LincRNA00494 and SRCIN1 reporters. After transfection with miR-150-3p mimics and miR-150-3p inhibitor, overexpression of LincRNA00494 decreased the proliferation of the H358 (36%) and H1299 (29%) cell lines compared with that of the control cells, as shown by CCK-8 assays, whereas silencing LincRNA00494 promoted the proliferation of the H358 (47%) and H1299 (35%) cells. Tumor growth from LincRNA00494-overexpressing xenografts was significantly decreased; additionally, LincRNA00494 silencing substantially increased tumor growth compared with that of the control cells. Conclusions: Functional experiments revealed that LincRNA00494 inhibited NSCLC cell proliferation, which might be related to the suppression of SRCIN1, a tumor suppressor gene, by acting as a decoy for miR-150-3p. The data showed that LincRNA00494 might have antineoplastic effects during NSCLC tumorigenesis through its role as a ceRNA.

The genetic script of metastasis

Metastasis is a pivotal event that changes the course of cancers from benign and treatable to malignant and difficult to treat, resulting in the demise of patients. Understanding the genetic control of metastasis is thus crucial to develop efficient and sustainable targeted therapies. Here we discuss the alterations in epigenetic mechanisms, transcription, chromosomal instability, chromosome imprinting, non-coding RNAs, coding RNAs, mutant RNAs, enhancers, G-quadruplexes, and copy number variation to dissect the genetic control of metastasis. We conclude that the genetic control of metastasis is predominantly executed through epithelial to mesenchymal transition and evasion of cell death. We discuss how genetic regulatory mechanisms can be harnessed for therapeutic purposes to achieve sustainable control over cancer metastasis.

Long noncoding RNA SPRY4-IT1 promotes proliferation and metastasis of hepatocellular carcinoma via mediating TNF signaling pathway

Our previous studies have indicated that long noncoding RNA (lncRNA) SPRY4 intronic transcript 1 (SPRY4-IT1) was highly expressed in hepatocellular carcinoma (HCC). However, it still remained unclear how SPRY4-IT1 worked in tumorgenesis in HCC. In this study, we tested the overexpression of SPRY4-IT1 in HCC tissues and cells through a quantitative real-time polymerase chain reaction. Statistical analyses showed that the upregulation had an association with the tumor node metastasis stage, thrombin time, and alkaline phosphatase. Furthermore, SPRY4-IT1 could be involved in cell proliferation, metastasis, and the epithelial-to-mesenchymal transition (EMT) process in HCC in vitro and in vivo. RNA-sequencing and transcriptome analysis were carried out to explore the mechanism of SPRY4-IT1 in HCC. With SPRY4-IT1 being knocked down or overexpressed, the level of proteins in the tumor necrosis factor (TNF) signaling pathway changed. We detected the RNA binding protein heterogeneous nuclear ribonucleoprotein L (HNRNPL) as a SPRY4-IT1 interacting protein through RNA pull-down assay and liquid chromatography-mass spectrometry, then verified through RNA immunoprecipitation. Downregulation of HNRNPL induced the change of proteins observed on SPRY4-IT1 downregulation revealing the SPRY4-IT1: HNRNPL complex in the TNF signaling pathway and EMT process in HCC. In general, our experimental data and analysis demonstrated the role of SPRY4-IT1 in promoting progress and metastasis of HCC by the TNF signaling pathway.

Repression of lncRNA-SVUGP2 mediated by EZH2 contributes to the development of non-small cell lung cancer via brisking Wnt/β-catenin signal

To grab the possible impact of lncRNA-SVUGP2 in the biology and process of non-small cell lung cancer (NSCLC). Sixty paired NSCLC tumour and the adjacent non-tumour lung tissues were collected for detection of lncRNA-SVUGP2. lncRNA-SVUGP2 expression in NSCLC cells (SK-MES-1, A549, SPC-A1, and NCI-H1975) was also detected. lncRNA-SVUGP2 was overexpressed and depressed in A549 and H1975 cells, and the effects of lncRNA-SVUGP2 dysregulation on cell biological performances including viability, colony formation, apoptosis, migration and invasion were grabbed. Furthermore, the regulatory association of lncRNA-SVUGP2 vs. EZH2 in H1975 cells, as well as the association between lncRNA-SVUGP2 and Wnt/β-catenin pathway, was explored. lncRNA-SVUGP2 was depressed in NSCLC tissues and cells. Overexpression of lncRNA-SVUGP2 depressed proliferation, induced apoptosis, and suppressed migration and invasion of A549 and H1975 cells. In addition, lncRNA-SVUGP2 was repressed by EZH2 and was inversely correlated with EZH2 levels in H1975 cells. Repression of lncRNA-SVUGP2 potentially participated in the oncogenic function of EZH2. Besides, overexpression of lncRNA-SVUGP2 depressed the briskness of Wnt/β-catenin signal in H1975 cells. Our data reveal that lncRNA-SVUGP2 is under-expressed in NSCLC cells and the reduced expression of lncRNA-SVUGP2 may enhance the development and process of NSCLC by interacting with EZH2 and activating Wnt/β-catenin pathway.

Non-coding RNA and lung cancer progression

Lung cancer (LC) is a major killer disease globally. This situation is further supported by yearly increase in new LC cases and its poor 5-year survival which is less than 15%. Although a large percentage of LC cases have been attributed to smoking, a considerable amount of nonsmokers also develops this disease, thereby suggesting a genetic and/or epigenetic undertone to LC development. Several growth-related genes such as epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) as well as tumor suppressor genes such as p53 have been implicated in LC pathogenesis and progression. Likewise, the genome only contains approximately 1% of coding regions. Hence, noncoding portion of the genome such as noncoding RNAs (ncRNAs) has been studied and discovered to play a cogent role in LC pathogenesis. More precisely, microRNAs (miRNAs) and long ncRNAs (lncRNAs) have been studied for decades. Posttranscriptional gene modulation function of miRNAs is well established and characterized. Likewise, the antagonizing interaction between lncRNAs and miRNAs had also been proven to further control gene expression during healthy and disease conditions like LC. More recently, renewed attention toward circular RNAs [circular RNAs (circRNAs)] study showed that circRNAs can also sponge miRNAs to modulate gene expressions too. Hence, miRNAs, lncRNAs, and circRNAs seem to function within a circuit to optimally determine which gene is needed to be upregulated or downregulated in biological system. Therefore, this review will discuss important ncRNAs, namely miRNA, lncRNA, and circRNA in LC progression. Paracrine effect of exosomal ncRNA will be also reviewed. In addition, the prospect of these ncRNAs in enhancing better LC treatment will be highlighted as well.

Extracellular Vesicles and Epigenetic Modifications Are Hallmarks of Melanoma Progression

Cutaneous melanoma shows a high metastatic potential based on its ability to overcome the immune system's control. The mechanisms activated for these functions vary extremely and are also represented by the production of a number of extracellular vesicles including exosomes. Other vesicles showing a potential role in the melanoma progression include oncosomes and melanosomes and the majority of them mediate tumor processes including angiogenesis, immune regulation, and modifications of the micro-environment. Moreover, a number of epigenetic modifications have been described in melanoma and abundant production of altered microRNAs (mi-RNAs), non-coding RNAs, histones, and abnormal DNA methylation have been associated with different phases of melanoma progression. In addition, exosomes, miRNAs, and other molecular factors have been used as potential biomarkers reflecting disease evolution while others have been suggested to be potential druggable molecules for therapeutic application.

Long non-coding RNA in lung cancer

Lung cancer is the leading cause of cancer-related death worldwide. Owing to the difficulty in early diagnosis and the lack of effective treatment strategies, the 5-year survival rates for lung cancer remain very low. With the development of whole genome and transcriptome sequencing technology, long non-coding RNA (lncRNA) has attracted increasing attention. LncRNAs regulate gene expression at the epigenetic, transcriptional and post-transcriptional levels and are widely involved in a variety of diseases, including tumorigenesis. In lung cancer studies, multiple differentially expressed lncRNAs have been identified; several lncRNAs were identified as oncogenic lncRNAs with tumor-driving effects, while other lncRNAs play a role in tumor inhibition and are called tumor-suppressive lncRNAs. These tumor-suppressive lncRNAs are involved in multiple physiological processes such as cell proliferation, apoptosis, and metastasis and thus participate in tumor progression. In this review, we discussed the oncogenic and tumor-suppressive lncRNAs in lung cancer, as well as their biological functions and regulatory mechanisms. Furthermore, we found the potential significance of lncRNAs in clinical diagnosis and treatment.

LncRNA SPRY4-IT1 regulates breast cancer cell stemness through competitively binding miR-6882-3p with TCF7L2

SPRY4-intronic transcript 1 has been found in several kinds of cancers, but the role of SPRY4-IT1 in breast cancer stem cells has not been studied. We investigated whether SPRY4-IT1 is involved in the promotion of breast cancer stem cells (BCSCs). We used qRT-PCR to detect the expression of SPRY4-IT1 in MCF-7 cells and MCF-7 cancer stem cells (MCF-7 CSCs). The effects of SPRY4-IT1 on the proliferation and renewal ability of breast cancer cells were investigated by in vitro and in vivo assays (ie in situ hybridization, colony formation assay, sphere formation assay, flow cytometry assay, western blotting, xenograft model and immunohistochemistry). The mechanism of SPPRY4-IT1 as a ceRNA was studied by a dual-luciferase reporter assay and bioinformatic analysis. In our study, SPRY4-IT1 was up-regulated in MCF-7 CSCs compared with MCF-7 cells, and high SPRY4-IT1 expression was related to reduced breast cancer patient survival. Furthermore, SPRY4-IT1 overexpression promoted breast cancer cell proliferation and stemness in vitro and in vivo. In addition, SPRY4-IT1 knockdown suppressed BCSC renewal ability and stemness maintenance in vivo and in vitro. The dual-luciferase reporter assays indicated that SPRY4-IT1 as a sponge for miR-6882-3p repressed transcription factor 7-like 2 (TCF7L2) expression. Taken together, these findings demonstrated that SPRY4-IT1 promotes proliferation and stemness of breast cancer cells as well as renewal ability and stemness maintenance of BCSCs by increasing the expression of TCF7L2 through targeting miR-6882-3p.

Knockdown of lncRNA MIAT inhibits proliferation and cisplatin resistance in non-small cell lung cancer cells by increasing miR-184 expression

Accumulating evidence has demonstrated the important role of long non-coding RNA myocardial infarction-associated transcript (MIAT) in tumorigenesis as a potential oncogene. However, the function of MIAT in non-small cell lung cancer (NSCLC) has yet to be completely elucidated. The present study demonstrated that MIAT expression was significantly upregulated in NSCLC tissues, particularly in aggressive cases, and was highly associated with a poor prognosis. In addition, the upregulated expression of MIAT was observed in cisplatin (CDDP)-resistant H1299 cells. Knockdown of MIAT inhibited the proliferation of NSCLC cells and enhanced the sensitivity of NSCLC cells to CDDP in vitro and in vivo. Further functional analysis demonstrated that MIAT partially exerted its oncogenic effect by upregulating the expression of splicing factor 1 (SF1), by serving as a microRNA (miR)-184 sponge. In conclusion, the present study identified that MIAT functions as a competitive endogenous RNA of miR-184to modulate SF1 expression in NSCLC, which provides a novel insight into the potential therapeutic application of MIAT in NSCLC progression.

Long non-coding RNAs in non-small cell lung cancer: functions and distinctions from other malignancies

Lung cancer leads to the most cancer-related death in the world. It was shown from the increasing evidences that long non-coding RNAs (lncRNAs) are emerging as molecules for diagnosis, prognosis and even therapy of lung cancer and other malignancies. The biological functions or involved signaling pathways of lncRNAs are always found to be inconsistent among different types of malignancies. However, no available literature has systemically summarized differences in the functions and underlying molecular mechanisms of lncRNAs between lung cancer and other cancers. In this review, the biological functions and molecular mechanisms of lncRNAs in lung cancer were introduced. Furthermore, their functional differences between lung cancer and other malignancies were discussed. Finally, their potential clinical applications in future lung cancer therapy were focused on.

Methylation and transcriptome analysis reveal lung adenocarcinoma-specific diagnostic biomarkers

Background

DNA methylation can regulate the role of long noncoding RNAs (lncRNAs) in the development of lung adenocarcinoma (LUAD). The present study aimed to identify methylation-driven lncRNAs and mRNAs as biomarkers in the prognosis of LUAD using bioinformatics analysis.

Methods

Differentially expressed RNAs were obtained using the edge R package from 535 LUAD tissues and 59 adjacent non-LUAD tissues. Differentially methylated genes were obtained using the limma R package from 475 LUAD tissues and 32 adjacent non-LUAD tissues. Methylation-driven mRNA and lncRNA were obtained using the MethylMix R package from 465 LUAD tissues with matched DNA methylation and RNA expression and 32 non-LUAD tissues with DNA methylation. Gene ontology and ConsensusPathDB pathway analysis were performed to identify functional enrichment of methylation-driven mRNAs. Univariate and multivariate Cox regression analyses were performed to identify the independent effect of each variable for predicting the prognosis of LUAD. Kaplan–Meier curve analysis of DNA methylation and gene expression might provide potential prognostic biomarkers for LUAD patients.

Results

A total of 99 methylation-driven mRNAs and 17 methylation-driven lncRNAs were obtained. Univariate and multivariate Cox regression analysis showed that 6 lncRNAs (FOXE1, HOXB13-AS1_2, VMO1, HIST1H3F, AJ003147.8, ASXL3) were retrieved to construct a predictive model associated with overall survival in LUAD patients. Combined DNA methylation and gene expression survival analysis revealed that 4 lncRNAs (AC023824.1, AF186192.1, LINC01354 and WASIR2) and 8 mRNAs (S1PR1, CCDC181, F2RL1, EFS, KLHDC9, MPV17L, GKN2, ITPRIPL1) might act as independent biomarkers for the prognosis of LUAD.

Conclusions

Methylation-driven lncRNA and mRNA contribute to the survival of LUAD, and 4 lncRNAs and 8 mRNAs might be potential biomarkers for the prognosis of LUAD.

LINK-A lncRNA is upregulated in metastatic non-small cell lung cancer and is associated with poor prognosis

Long intergenic non-coding RNA for kinase activation (LINK-A) has been characterized as an oncogenic long non-coding RNA (lncRNA) in triple-negative breast cancer. However, its involvement in non-small cell lung cancer (NSCLC) remains unknown. The aim of the present study was to investigate the involvement of LINK-A in NSCLC. Expression of LINK-A lncRNA in the plasma of patients with NSCLC collected on the day of admission and the day of discharge, and in the plasma of healthy controls, was detected by reverse transcription-quantitative PCR. Diagnostic values of plasma LINK-A for metastatic NSCLC were evaluated by receiver operating characteristic curve analysis. A LINK-A lncRNA expression vector was constructed and transfected into human NSCLC cell lines, and the effects on cell migration and invasion, and Akt activation were detected by Transwell and Matrigel assays, and western blotting, respectively. Plasma levels of LINK-A were found to be significantly higher in patients with different types of metastatic NSCLC than in patients with non-metastatic NSCLC and healthy controls. Plasma levels of LINK-A were lower in patients with metastatic NSCLC on the day of discharge than on the day of admission. Patients with high plasma LINK-A had a higher mortality rate and lower progression-free survival rate within 2 years of discharge. In conclusion, LINK-A is overexpressed in metastatic NSCLC, and may promote the migration and invasion of NSCLC by activating Akt signaling.

Long non‑coding RNAs in lung cancer: Regulation patterns, biologic function and diagnosis implications (Review)

Lung cancer is the most common malignancy with the highest mortality worldwide. Emerging research has demonstrated that long non-coding RNAs (lncRNAs), a key genomic product, are commonly dysregulated in lung cancer and have significant functions in lung cancer initiation, progression and therapeutic response. lncRNAs may interact with DNA, RNA or proteins, as tumor suppressor genes or oncogenes, to regulate gene expression and cell signaling pathways. In the present review, first a summary was presented of the causal effects of dysregulated lncRNAs in lung cancer. Next, the function and specific mechanisms of lncRNA-mediated tumorigenesis, metastasis and drug resistance in lung cancer were discussed. Finally, the potential roles of lncRNAs as biomarkers for lung cancer were explored.

A long non-coding RNA regulates cadherin transcription and susceptibility to Bt toxin Cry1Ac in pink bollworm, Pectinophora gossypiella

Extensive planting of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has spurred increasingly rapid evolution of resistance in pests. In the pink bollworm, Pectinophora gossypiella, a devastating global pest, resistance to Bt toxin Cry1Ac produced by transgenic cotton is linked with mutations in a gene (PgCad1) encoding a cadherin protein that binds Cry1Ac in the larval midgut. We previously reported a long non-coding RNA (lncRNA) in intron 20 of cadherin alleles associated with both resistance and susceptibility to Cry1Ac. Here we tested the hypothesis that reducing expression of this lncRNA decreases transcription of PgCad1 and susceptibility to Cry1Ac. Quantitative RT-PCR showed that feeding susceptible neonates small interfering RNAs (siRNAs) targeting this lncRNA but not PgCad1 decreased the abundance of transcripts of both the lncRNA and PgCad1. Moreover, neonates fed the siRNAs had lower susceptibility to Cry1Ac. The results imply that the lncRNA increases transcription of PgCad1 and susceptibility of pink bollworm to Cry1Ac. The results suggest that disruption of lncRNA expression could be a novel mechanism of pest resistance to Bt toxins.

The association and prognostic impact of enhancer of zeste homologue 2 expression and epithelial-mesenchymal transition in resected lung adenocarcinoma

OBJECTIVES

Epithelial-mesenchymal transition (EMT) and the histone methyltransferase Enhancer of Zeste Homologue 2 (EZH2) are important regulators of lung cancer progression and metastasis. Although recent studies support the correlation between EZH2 expression and EMT, no reports have investigated their association using immunohistochemistry or explored their prognostic impact on lung adenocarcinoma. The aim of this study was to elucidate the association between EZH2 and EMT, and their prognostic significance.

METHODS

EZH2 and the EMT markers E-cadherin and Vimentin were examined by IHC in lung adenocarcinoma specimens that were resected from 2003-2012. Associations between EZH2 and EMT markers and their correlations with survival were analyzed.

RESULTS

We enrolled 350 patients, approximately 70% of whom were diagnosed as pathological stage I. The rates of positive E-cadherin, Vimentin, and EZH2 expression were 60.3%, 21.4%, and 52.0%, respectively. There was a significant positive correlation between EZH2 and Vimentin expression (p = 0.008), and EZH2 scores were higher in the Mesenchymal group (p = 0.030). In multivariate analysis, EZH2 was an independent predictor of Vimentin expression, and vice versa. EMT and EZH2 overexpression were significantly correlated with poor disease-free and overall survival. Furthermore, the Epithelial group with high EZH2 expression had significantly worse disease-free and overall survival. Positive staining for EMT markers was unfavorable regarding disease-free survival among patients with low EZH2 expression.

CONCLUSIONS

EMT and high EZH2 expression were associated with poor NSCLC prognoses. Vimentin is a key factor linking EMT and EZH2 in lung adenocarcinoma.

Long noncoding RNA STXBP5-AS1 inhibits cell proliferation, migration, and invasion via preventing the PI3K/AKT against STXBP5 expression in non-small-cell lung carcinoma

Long noncoding RNAs participate in carcinogenesis and tumor progression in non-small-cell lung carcinoma (NSCLC), but the mechanisms underlying NSCLC tumorigenesis remain to be fully elucidated. Here, we reported the functional role and potential mechanism of long noncoding RNA syntaxin-binding protein 5-antisense RNA 1 (STXBP5-AS1) in NSCLC. First, our data revealed that the expression levels of STXBP5-AS1 in 31 NSCLC tissues were lower than in adjacent tissues using quantitative polymerase chain reaction (qPCR) and its expression was significantly associated with tumor metastasis of NSCLC patients. Moreover, CCK-8, scratch wound healing and transwell assay suggested that upregulation of STXBP5-AS1 repressed the proliferation, migration, and invasion in A549, NCI-H292, and NCI-H460 cells. To explore the potential mechanism of STXBP5-AS1 in NSCLC, we first investigated the relationship among STXBP5-AS1, STXBP5, and AKT1 in A549 cells. Results indicated that STXBP5-AS1 was negatively related with STXBP5 and AKT1 at messenger RNA expression level using qPCR. In addition, we observed that STXBP5-AS1 had reverse effects on the protein levels of STXBP5 and phosphorylated AKT1 (p-AKT1) in A549 cells via Western blot assay, despite no significant effects on AKT1. Subsequently, LY294002, as the phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT) pathway inhibitor, was used to further confirm the regulatory mechanism of STXBP5-AS1, which showed that knockdown of STXBP5-AS1 could rescue the expression of STXBP5 and p-AKT1 protein expression levels in A549 cells. Taken together, our results suggested that STXBP5-AS1, as a tumor suppressor, inhibits cell proliferation, migration, and invasion by preventing the PI3K/AKT against STXBP5 expression in NSCLC.

Long Noncoding RNA and Epithelial Mesenchymal Transition in Cancer

Epithelial-mesenchymal transition (EMT) is a multistep process that allows epithelial cells to acquire mesenchymal properties. Fundamental in the early stages of embryonic development, this process is aberrantly activated in aggressive cancerous cells to gain motility and invasion capacity, thus promoting metastatic phenotypes. For this reason, EMT is a central topic in cancer research and its regulation by a plethora of mechanisms has been reported. Recently, genomic sequencing and functional genomic studies deepened our knowledge on the fundamental regulatory role of noncoding DNA. A large part of the genome is transcribed in an impressive number of noncoding RNAs. Among these, long noncoding RNAs (lncRNAs) have been reported to control several biological processes affecting gene expression at multiple levels from transcription to protein localization and stability. Up to now, more than 8000 lncRNAs were discovered as selectively expressed in cancer cells. Their elevated number and high expression specificity candidate these molecules as a valuable source of biomarkers and potential therapeutic targets. Rising evidence currently highlights a relevant function of lncRNAs on EMT regulation defining a new layer of involvement of these molecules in cancer biology. In this review we aim to summarize the findings on the role of lncRNAs on EMT regulation and to discuss their prospective potential value as biomarkers and therapeutic targets in cancer.

lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE) Promotes Proliferation and Inhibits Apoptosis in Non-Small Cell Lung Cancer Cells by Regulating the miR-641/CDK6 Axis

BACKGROUND The lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE) gene has been reported as a potential oncogene in NSCLC. Nevertheless, the molecular mechanism of CRNDE in NSCLC progression remains largely unknown. MATERIAL AND METHODS qRT-PCR assay was performed to detect the expression levels of CRNDE, miR-641, and cyclin-dependent kinase 6 (CDK6) in NSCLC. Western blot assay was employed to assess CDK6 protein level in treated NSCLC cells. si-CRNDE#1, si-CRNDE#2, miR-641 mimics, miR-641 inhibitors, or Vector-CDK6 were transfected into NSCLC cells to change the expression levels of CRNDE, miR-641, or CDK6. Dual-luciferase reporter assay was performed to validate the direct interrelated miRNA of CRNDE and the potential target of miR-641. MTT and flow cytometry assays were performed to assess the capacities of cell proliferation and apoptosis, respectively. RESULTS CRNDE level was upregulated in NSCLC, and its knockdown suppressed NSCLC cells proliferation and enhanced apoptosis, whereas miR-641 antagonized the regulatory effect of CRNDE knockdown by directly binding to CRNDE. Moreover, CDK6 was a target of miR-641 and miR-641 exerted anti-proliferation and pro-apoptosis effects through CDK6. CONCLUSIONS CRNDE promoted proliferation and inhibited apoptosis of NSCLC cells at least in part by regulating the miR-641/CDK6 axis, suggesting that CRNDE is a potential therapeutic target for NSCLC treatment.

Decreased expression of NEDD4L contributes to NSCLC progression and metastasis

Recent evidence indicated that neural precursor cell expressed, developmentally down-regulated 4-like (NEDD4L) has a critical role in the regulation of cellular processes such as apoptosis, transport and metastasis, and is downregulated in several types of cancers. However, the role of NEDD4L in non-small cell lung cancer (NSCLC) has not been fully elucidated. In this study, we demonstrated that NEDD4L was downregulated in NSCLCs. This downregulation correlated with lymph node invasion, advanced stage and poor survival. In vitro experiments revealed that NEDD4L significantly suppressed cell proliferation, migration and invasion abilities. Further in vivo assay demonstrated that knocking down of NEDD4L enhanced the tumor metastasis of NSCLC cells. Moreover, we found that Polycomb group protein enhancer of zeste homologue 2 (EZH2) mediated H3K27 methylation was involved in the downregulation of NEDD4L. Knocking down of EZH2 restored the expression of NEDD4L. Further examined by luciferase reporter assay indicated the EZH2 regulated the transcription activity of NEDD4L. In clinical samples, EZH2 was inversely correlated with NEDD4L expression. In summary, NEDD4L acted as a tumor suppressor gene in NSCLC and targeting EZH2 could upregulate NEDD4L expression, which might serve as a novel approach for NSCLC.

Molecular mechanisms of long noncoding RNAs-mediated cancer metastasis

Cancer metastasis is a multistep process that requires cancer cells to leave the primary site, survive in the blood stream, and finally colonize at a distant organ. It is the major cause of cancer morbidity and mortality. The organ-specific colonization requires close interaction and communication between cancer cells and host organs. Noncoding RNAs represent the majority of the transcriptome, with long noncoding RNAs (lncRNAs) making up a significant proportion. It has been suggested that lncRNAs play a key role in all stages of tumorigenesis and metastasis. This review will provide an overview of how lncRNAs are involved in cancer cell colonization in specific organ sites and the underlying mechanisms as well as therapeutic strategies.

From biomarkers to therapeutic targets-the promises and perils of long non-coding RNAs in cancer

Biomarker-driven personalized cancer therapy is a field of growing interest, and several molecular tests have been developed to detect biomarkers that predict, e.g., response of cancers to particular therapies. Identification of these molecules and understanding their molecular mechanisms is important for cancer prognosis and the development of therapeutics for late stage diseases. In the past, significant efforts have been placed on the discovery of protein or DNA-based biomarkers while only recently the class of long non-coding RNA (lncRNA) has emerged as a new category of biomarker. The mammalian genome is pervasively transcribed yielding a vast amount of non-protein-coding RNAs including lncRNAs. Hence, these transcripts represent a rich source of information that has the potential to significantly contribute to precision medicine in the future. Importantly, many lncRNAs are differentially expressed in carcinomas and they are emerging as potent regulators of tumor progression and metastasis. Here, we will highlight prime examples of lncRNAs that serve as marker for cancer progression or therapy response and which might represent promising therapeutic targets. Furthermore, we will introduce lncRNA targeting tools and strategies, and we will discuss potential pitfalls in translating these into clinical trials.

Upregulation of the long non-coding RNA SPRY4-IT1 predicts poor prognosis in breast cancer

BACKGROUND

The upregulation of long non-coding RNA SPRY4 intronic transcript 1 (lncRNA SPRY4-IT1) has been observed in breast cancer (BC). However, there is no previous study of the relationship between SPRY4-IT1 and patient prognosis in BC. This study investigated the prognostic value of SPRY4-IT1 in BC patients.

METHODS

The relative expression levels of SPRY4-IT1 were detected by RT-qPCR in 102 paired BC tissues and adjacent noncancerous tissues. The association of SPRY4-IT1 expression with clinicopathological features and prognosis was statistically analyzed.

RESULTS

The findings revealed that the SPRY4-IT1 expression was significantly upregulated in clinical BC tissues compared to adjacent normal tissues (P < 0.001). Furthermore, the SPRY4-IT1 level was significantly associated with tumor size (P = 0.009), TNM stage (P = 0.0008) and lymph node metastasis (P = 0.01). Using a Kaplan-Meier analysis, it was shown that patients with high SPRY4-IT1 expression had a significantly poor overall survival (OS) rate (P = 0.0056) and a disease-free survival (DFS) rate (P = 0.0001). Moreover, multivariate Cox analysis revealed that SPRY4-IT1 expression was an independent poor prognostic factor for both OS (P = 0.024) and DFS (P = 0.025) in BC patients.

CONCLUSIONS

SPRY4-IT1 expression is an independent prognostic factor for patients with BC and may serve as a potential biomarker to predict prognosis in BC patients.

MEG3: an Oncogenic Long Non-coding RNA in Different Cancers

Long noncoding RNAs (lncRNAs) have recently considered as central regulators in diverse biological processes and emerged as vital players controlling tumorigenesis. Several lncRNAs can be classified into oncogenes and tumor suppressor genes depending on their function in cancer. A maternally expressed gene 3 (MEG3) gene transcripts a 1.6 kb lncRNA whose act as an antitumor component in different cancer cells, such as breast, liver, glioma, colorectal, cervical, gastric, lung, ovarian and osteosarcoma cancer cells. The present review highlights biological function of MEG3 to repress tumor through regulating the major tumor suppressor genes p53 and Rb, inhibiting angiogenesis-related factor, or controlling miRNAs. On the other hand, previous studies have also suggested that MEG3 mediates epithelial-mesenchymal transition (EMT). However, deregulation of MEG3 is associated with the  development and progression of cancer, suggesting that MEG3 may function as a potential biomarker and therapeutic target for human cancers.

Interference from LncRNA SPRY4-IT1 restrains the proliferation, migration, and invasion of melanoma cells through inactivating MAPK pathway by up-regulating miR-22-3p

Melanoma is a common malignancy with a low survival rate worldwide. Long non-coding RNA Sprouty4-Intron 1 (SPRY4-IT1) is correlated with various cancers, including melanoma. Herein, the underlying molecular mechanisms of SPRY4-IT1 in melanoma were characterized. We found that SPRY4-IT1 level was upregulated in melanoma cells lines compared to the normal skin cells, while miR-22-3p was downregulated. According to of bioinformatics analysis, SPRY4-IT1 was a hypothetic target of miR-22-3p, and knockdown SPRY4-IT1 by sh-RNA (sh-SPRY4-IT1) markedly elevated the miR-22-3p level. Also, the target relationship was further confirmed by dual luciferase reporter assay. In addition, low-expression of SPRY4-IT1 impeded cell proliferation, invasion, migration, and epithelial-mesenchymal transition. Furthermore, western blot assay indicated that the enhanced miR-22-3p further decelerated the phosphorylation of p38MAPK, MAPKAPK and Hsp27, which indicates that miR-22-3p could inactivate the p38MAPK/MAPKAPK/Hsp27 signaling pathway. Overall, our results show that sh-SPRY4-IT1 inhibits cell proliferation and motility through inactivating MAPK signaling by up-regulating miR-22-3p. Therefore, designing targeted drugs against SPRY4-IT1 provides a new direction for the treatment of melanoma.

TSPAN7 promotes the migration and proliferation of lung cancer cells via epithelial-to-mesenchymal transition

PURPOSE

To explore the effects and mechanisms of tetraspanin TSPAN7 on the progression of non-small-cell lung cancer (NSCLC) cells.

PATIENTS AND METHODS

All 125 lung cancer specimens and 60 metastatic tissues were obtained from patients diagnosed with NSCLC, and we used immunohistochemistry to detect the expression of TSPAN7 in NSCLC tissues and adjacent normal tissues. Cell proliferation and invasion ability were determined by MTT, colony formation, and cell migration. The relative protein expression level was analyzed by Western blot analysis.

RESULTS

Our clinical data showed that among 125 patients with lung cancer, TSPAN7 was associated with lymph node status, differentiation, tumor size, and poor prognosis. TSPAN7 knockout inhibited cell proliferation and migration. In addition, TSPAN7 increased the expression of N-cadherin in NSCLC cells by reducing the expression of E-cadherin and vimentin and promoting the cell epithelial-mesenchymal transition (EMT) process. Xenograft transplantation model confirmed the role of TSPAN7 in NSCLC metastasis.

CONCLUSION

TSPAN7-mediated EMT is the key to NSCLC migration. TSPAN7 is a potential target for NSCLC therapy.

LONG-NONCODING RNAs in gastroesophageal cancers

Despite continuing improvements in multimodal therapies, gastro-esophageal malignances remain widely prevalent in the population and is characterized by poor overall and disease-free survival rates. Due to the lack of understanding about the pathogenesis and absence of reliable markers, gastro-esophageal cancers are associated with delayed diagnosis. The increasing understanding about cancer's molecular landscape in the recent years, offers the possibility of identifying 'targetable' molecular events and in particular facilitates novel treatment strategies and development of biomarkers for early stage diagnosis. At least 98% of our genome is actively transcribed into non-coding RNAs encompassing long non-coding RNAs (lncRNAs) constituted of transcripts longer than 200 nucleotides with no protein-coding capacity. Many studies have demonstrated that lncRNAs are functional genomic elements playing pivotal roles in main oncogenic processes. LncRNA can act at multiple levels developing a complex molecular network that can modulate directly or indirectly the expression of genes involved in tumorigenesis. In this review, we focus on lncRNAs as emerging players in gastro-esophageal carcinogenesis and critically assess their potential as reliable noninvasive biomarkers and in next generation targeted therapies.

The N-terminal polypeptide derived from vMIP-II exerts its anti-tumor activity in human breast cancer by regulating lncRNA SPRY4-IT1

Accumulating evidence demonstrates that long non-coding RNA (lncRNA) sprouty4-intron transcript 1 (lncRNA SPRY4-IT1) plays a vital role in the development of breast cancer. However, the underlying mechanism has not been eventually illuminated. We aimed to explore the biological activity of lncRNA SPRY4-IT1 in breast cancer cells and whether N-terminal polypeptide derived from viral macrophage inflammatory protein II (NT21MP) could exert its anti-tumor effect by regulating lncRNA SPRY4-IT1 and its target gene SKA2 Real-time RT-PCR, Western blotting, wound healing, and invasion assays were used to achieve this goal. We found that lncRNA SPRY4-IT1 was highly expressed in breast cancer cells. Moreover, NT21MP markedly inhibited biological effects of breast cancer cells by regulating lncRNA SPRY4-IT1, which was partially achieved through SKA2. Our findings suggested that lncRNA SPRY4-IT1 could serve as a novel biomarker by NT21MP for breast cancer.

Role of lncRNA and EZH2 Interaction/Regulatory Network in Lung Cancer

Lung cancer is the leading cause of cancer-related deaths worldwide. Long non-coding RNAs (lncRNAs) are non-protein-coding transcripts and longer than 200 nucleotides. LncRNAs have been demonstrated to modulate gene expression at transcriptional, post-transcriptional, as well as epigenetic levels in lung cancer. Interestingly, compelling studies have revealed that lncRNAs participated in the EZH2 oncogenic regulatory network. EZH2 plays an important role in the initiation, progression and metastasis of cancer. On one hand, lncRNAs can directly bind to EZH2, recruit EZH2 to the promoter region of genes and repress their expression. On the other hand, lncRNAs can also serve as EZH2 effectors or regulators. In this review, we summarized the types of lncRNA-EZH2 interaction and regulatory network identified till date and discussed their influence on lung cancer. Better understanding regarding the interaction and regulatory network will provide new insights on lncRNA- or EZH2-based therapeutic development in lung cancer.

SP1-induced lncRNA-ZFAS1 contributes to colorectal cancer progression via the miR-150-5p/VEGFA axis

Increasing long non-coding RNAs (lncRNAs) have been reported to play key roles in the development and progression of various malignancies. ZNFX1 antisense RNA1 (ZFAS1) has been reported to be aberrant expression and suggested as a tumor suppressor or oncogene in many cancers. However, the biological role and underlying molecular mechanism of ZFAS1, especially the miRNA sponge role of which in CRC remain largely unknown. We found that ZFAS1 expression was higher in CRC tissues, where it was associated with poor overall survival (OS), we also showed that ZFAS1 upregulation was induced by nuclear transcription factor SP1. Moreover, ZFAS1 and VEGFA are both targets of miR-150-5p, while ZFAS1 binds to miR-150-5p in an AGO2-dependent manner. Additionally, ZFAS1 upregulation markedly promoted as well as ZFAS1 knockdown significantly suppressed CRC cell proliferation, migration, invasion and angiogenesis, and the inhibitory effect caused by ZFAS1 knockdown could be reversed by antagomiR-150-5p. Lastly, we demonstrated that ZFAS1 knockdown inhibited EMT process and inactivated VEGFA/VEGFR2 and downstream Akt/mTOR signaling pathway in CRC. Our data demonstrated that SP1-induced ZFAS1 contributed to CRC progression by upregulating VEGFA via competitively binding to miR-150-5p, which acts as a tumor suppressor by targeting VEGFA in CRC.

Long non-coding RNAs involved in metastasis of gastric cancer

Gastric cancer (GC) is one of the most frequently diagnosed malignant diseases. The molecular mechanisms of metastasis remain unclear. Recently, studies have shown that long non-coding RNAs (lncRNAs) play critical roles in metastasis. Therefore, deeper understanding of this mechanism could provide potential diagnostic tools and therapeutic targets for metastatic GC. This review focuses on dysregulated lncRNAs in GC metastases. Due to the identification of multiple diverse mechanisms involved in GC metastasis, we classified them into seven categories, including lncRNAs related to epithelial-mesenchymal transition, regulation of degradation of extracellular matrix, angiopoiesis, vasculogenic mimicry, and immunologic escape. As the TNM stage is pivotal for evaluating the severity and prognosis of GC patients, we summarize the lncRNAs relevant to lymphatic metastasis, distant metastasis and TNM classification. This review summarizes the lncRNAs related to metastasis, which may provide insight into the mechanisms, and provide potential markers for prognostic prediction and monitoring the relapse of GC.

TGF-β/SMAD4-Regulated LncRNA-LINP1 Inhibits Epithelial-Mesenchymal Transition in Lung Cancer

Lung cancer is the leading cause of cancer related deaths worldwide. TGF-β-induced epithelial-mesenchymal transition (EMT) is a key cell-intrinsic identity for tumor cell migration, invasion, and stemness acquisition in cancer metastasis. Long noncoding RNAs (lncRNAs) have not been fully investigated for their involvement in regulating TGF-β-induced EMT and metastasis in lung cancer. Here, we demonstrated that the transcription of lncRNA in nonhomologous end joining (NHEJ) pathway 1 (LINP1) was inhibited by TGF-β1 in a SMAD4-dependent manner. LINP1 suppressed EMT of lung cancer cells, thereby controlling cancer cell migration, invasion, and stemless. Moreover, LINP1 inhibited TGF-β-induced EMT and cell invasion in lung cancer cells. Our study reveals the role of LINP1 in the regulation of TGF-β-induced EMT in human lung cancer.

lncRNA involvement in hepatocellular carcinoma metastasis and prognosis

Eukaryotic lncRNAs are RNA molecules defined to be greater than 200 bp in length that are not translated to a protein and operate through several mechanisms, including participating in chromatin remodeling and methylation, influencing the integrity and stability of proteins and complexes, or acting as a sponge for miRNA inhibition. A number of recent studies have concentrated on the relationship between long non-coding RNAs (lncRNAs) and cancer. Hepatocellular carcinoma (HCC) is the most prevalent histological type of liver tumors, accounting for about 80 % of the cases worldwide. Lack of proper molecular markers for diagnosis of HCC and treatment evaluation is a significant problem. Dysregulated expression of HCC-related lncRNAs such as MEG-3, MALAT1, HULC, HOTAIR, and H19 have been identified and closely related with tumorigenesis, metastasis, prognosis and diagnosis. In this review, we summarized recent highlighted functions and molecular mechanisms of the most extensively studied lncRNAs in the pathophysiology of hepatocellular carcinoma and their potential for serving as probable therapeutic targets.

[Progress of Long Non-coding RNA in Non-small Cell Lung Cancer]

肺癌是世界上常见的恶性肿瘤之一，其发病率和死亡率都居全部恶性肿瘤的首位。长链非编码RNA（lncRNA）是一类转录长度超过200个核苷酸且无蛋白质编码功能的RNA，但在表观遗传学调控、细胞周期调控和细胞分化调控等众多生命活动中发挥重要作用。研究发现lncRNA在非小细胞肺癌（non-small cell lung cancer, NSCLC）组织和血液中异常表达，且对肿瘤细胞的增殖、迁移、侵袭和凋亡发挥了重要调节作用，与肿瘤的发生发展密切相关。探索lncRNA在NSCLC中的作用机制，有助于NSCLC的早期诊断，靶向治疗及改善预后。因此本文就lncRNA与NSCLC的发生、诊断、治疗和预后的最新研究进展做一阐述，以期为NSCLC的防治提供新思路。

Emerging role of lncRNAs in the normal and diseased intestinal barrier

OBJECTIVE

A significant effort has been made to understand the intestinal barrier, but the effective means to prevent, reduce, and restore intestinal mucosal damage remains unclear. Recently, a few of studies have explained the mechanism of the intestinal barrier in long noncoding RNAs (lncRNAs). This review aims to summarize recent views on the function of lncRNAs in the intestinal barrier and discuss the emerging role of lncRNAs in intestinal barrier diseases caused by inflammatory diseases.

METHODS

Observations led us to believe that lncRNAs participate in inflammatory responses, cell proliferation, and control microbial susceptibility. In view of these, lncRNAs have been proved to involve in the intestinal barrier.

RESULTS

lncRNAs directly or indirectly affect TJ mRNA translation and intestinal epithelial cells (IECs) paracellular permeability, as well as IECs proliferation and susceptibility to apoptosis, to modulate the function of the intestinal barrier. miRNAs play a pivotal role in this process.

CONCLUSIONS

lncRNAs have been shown to be fundamentally involved in intestinal mucosal regeneration, protection, and epithelial barrier function. It may emerge as new and potential factors to be evaluated in the intestinal barrier diseases caused by acute pancreatitis, inflammatory bowel diseases, and imbalance of intestinal flora.

LncRNA KCNQ1OT1 regulates proliferation and cisplatin resistance in tongue cancer via miR-211-5p mediated Ezrin/Fak/Src signaling

Numerous findings have demonstrated that long noncoding RNA (lncRNA) dysregulation plays a key role in many human neoplasms, including tongue squamous cell carcinoma (TSCC), yet the potential mechanisms of lncRNAs in chemo-resistance remain elusive. Our research showed that the lncRNA KCNQ1OT1 was upregulated in chemo-insensitive TSCC tissues compared with chemo-sensitive TSCC specimens. Meanwhile, high KCNQ1OT1 expression was closely correlated with poor prognosis. Furthermore, KCNQ1OT1 promoted TSCC proliferation and conferred TSCC resistance to cisplatin-induced apoptosis in vitro and in vivo. Using online database analysis, we predicted that the lncRNA KCNQ1OT1 facilitates tumor growth and chemo-resistance by acting as a competing endogenous RNA (ceRNA) to modulate the expression of miR-211-5p. And miR-211-5p upregulation significantly impaired TSCC proliferation and resumed TSCC chemo-sensitivity, which is contrary to the function of lncRNA KCNQ1OT1. Luciferase experiments confirmed that miR-211-5p harbor binding sites for the 3'-UTRof Ezrin mRNA, and Ezrin/Fak/Src signaling was activated in cisplatin-resistant TSCC cells. Finally, miR-211-5p inhibition in sh-KCNQ1OT1-expressing TSCC cells rescued the suppressed cell proliferation and cisplatin resistance induced by KCNQ1OT1 knockdown. In summary, our study has elucidated the role of the oncogenic lncRNA KCNQ1OT1 in TSCC growth and chemo-resistance, which may serve as a new target for TSCC therapy.

Increased expression of lncRNA ZEB1-AS1 in non-small cell lung cancer is associated with poor prognosis

BACKGROUND

Dysregulated long non-coding RNAs (lncRNAs) play critical roles in tumorigenesis and tumor progression. The purpose of this study was to investigate the relationship between lncRNA ZEB1-AS1 expression and non-small cell lung cancer (NSCLC) clinicopathological characteristics and prognosis.

METHODS

Expression levels of lncRNA ZEB1-AS1 in 183 NSCLC specimens were determined by quantitative real-time PCR (qRT-PCR). To clarify the clinical significance of lncRNA ZEB1-AS1 in NSCLC, we further explored the relationship between lncRNA ZEB1-AS1 expression and overall survival (OS).

RESULTS

In the present study, we found that lncRNA ZEB1-AS1 was upregulated in NSCLC tissues compared to adjacent non-tumor tissues. In addition, upregulated lncRNA ZEB1-AS1 expression was significantly associated with lymph node metastasis and TNM stage (P<0.05). Furthermore, patients with increased expression of lncRNA ZEB1-AS1 had poor OS (HR=3.202, 95% CI=2.018-5.078, P<0.001). Multivariate Cox proportional hazards model analysis demonstrated that high lncRNA ZEB1-AS1 expression was an independent poor prognostic factor for NSCLC patients.

CONCLUSION

Our study suggests that increased expression of lncRNA ZEB1-AS1 is related to adverse prognosis of NSCLC and may be a new prognostic biomarker and potential therapeutic target for NSCLC intervention.

Emerging roles of long non-coding RNAs in the toxicology of environmental chemicals

Environmental chemicals (ECs) are drawing great attention to their effects on health and their toxicological mechanisms are being investigated. Long non-coding RNA (lncRNA) is a class of RNA with more than 200 nucleotides and does not have protein coding potential. Recently, it is emerging as a star molecule that participates in a wide range of physiological and pathological processes. It has been reported to be abnormally expressed in diseases. As an epigenetic factor, lncRNAs play an important role in the response of organisms to environmental stress. Their roles in the toxicity of ECs are being identified. Altered expression profiles of lncRNAs have been explored after exposure to ECs. Various kinds of ECs are reported to disturb the expression of lncRNAs in vitro and in vivo. Then, dysregulated lncRNAs can affect the expression of target genes directly or indirectly via regulating the level of microRNAs. The network among lncRNAs, microRNAs and mRNAs can initiate or impede specific signaling pathway and lead to adverse outcome upon exposure to ECs. Recovery of the lncRNAs level by overexpression or knockdown technology diminished the effect induced by ECs. In the review, biological roles of lncRNAs are depicted. The lncRNAs involved in the toxicology are summarized. Types of ECs that have been reported to affect the expression of lncRNAs are categorized. The interaction between various types of ECs and lncRNAs is discussed.

Anti-tumor and anti-metastasis activities of honey bee larvae powder by suppressing the expression of EZH2

Honey bee larvae products have been widely used as traditional daily supplements and complementary medicine for health promotion. However, there is little scientific evidence about their bioactivities. This study was designed to examine the anti-tumor and anti-metastasis effects of honey bee larvae powder (HLP) and explore the underlying mechanism. A subcutaneous transplantation model (murine breast cancer cell 4T1-LUC) and lung metastasis model (murine melanoma cell B16-F10) were established to evaluate the anti-tumor and anti-metastasis effects of HLP. Honey bee larvae powder extract (HLE) was obtained by 70% ethanol extraction, and its chemical composition was determined according to physiochemical methods. Cell Counting Kit-8 assay was performed to test the cytotoxicity of HLE, and qRT-PCR assays were conducted to examine the mRNA levels of tumor marker EZH2 in HLE-treated tumor cells. In vivo xenograft tumor assays in BALB/c mice revealed dose-dependent suppression of tumor growth and lung metastasis showing an inhibition rate of 37.5% and 70.4% at 6 g/kg HLP-administered group with no toxicity to the animals. In vitro studies indicated that HLE showed no cytotoxicity to cancer cells at doses up to 1000 μg/mL, however, it significantly decreased EZH2 mRNA levels in HLE (1000 μg/mL)-treated B10-F10 cells (28.49%) and 4T1-LUC cells (26.75%). Further studies to elucidate the mechanisms involved and to isolate the active components of honey bee larva may provide more valuable information for its development and application in cancer treatment.

Role of EZH2 in cancer stem cells: from biological insight to a therapeutic target

Epigenetic modifications in cancer stem cells largely result in phenotypic and functional heterogeneity in many solid tumors. Increasing evidence indicates that enhancer of zeste homolog 2 (EZH2), the catalytic subunit of Polycomb repressor complex 2, is highly expressed in cancer stem cells of numerous malignant tumors and has a critical function in cancer stem cell expansion and maintenance. Here, we review up-to-date information regarding EZH2 expression patterns, functions, and molecular mechanisms in cancer stem cells in various malignant tumors and discuss the therapeutic potential of targeting EZH2 in tumors.

SP1-induced upregulation of lncRNA SPRY4-IT1 exerts oncogenic properties by scaffolding EZH2/LSD1/DNMT1 and sponging miR-101-3p in cholangiocarcinoma

Background

Accumulating evidence has indicated that long non-coding RNAs (lncRNAs) behave as a novel class of transcription products during multiple cancer processes. However, the mechanisms responsible for their alteration in cholangiocarcinoma (CCA) are not fully understood.

Methods

The expression of SPRY4-IT1 in CCA tissues and cell lines was determined by RT-qPCR, and the association between SPRY4-IT1 transcription and clinicopathologic features was analyzed. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were performed to explore whether SP1 could bind to the promoter region of SPRY4-IT1 and activate its transcription. The biological function of SPRY4-IT1 in CCA cells was evaluated both in vitro and in vivo. ChIP, RNA binding protein immunoprecipitation (RIP) and luciferase reporter assays were performed to determine the molecular mechanism of SPRY4-IT1 in cell proliferation, apoptosis and invasion.

Results

SPRY4-IT1 was abnormally upregulated in CCA tissues and cells, and this upregulation was correlated with tumor stage and tumor node metastasis (TNM) stage in CCA patients. SPRY4-IT1 overexpression was also an unfavorable prognostic factor for patients with CCA. Additionally, SP1 could bind directly to the SPRY4-IT1 promoter region and activate its transcription. Furthermore, SPRY4-IT1 silencing caused tumor suppressive effects via reducing cell proliferation, migration and invasion; inducing cell apoptosis and reversing the epithelial-to-mesenchymal transition (EMT) process in CCA cells. Mechanistically, enhancer of zeste homolog 2 (EZH2) along with the lysine specific demethylase 1 (LSD1) or DNA methyltransferase 1 (DNMT1) were recruited by SPRY4-IT1, which functioned as a scaffold. Importantly, SPRY4-IT1 positively regulated the expression of EZH2 through sponging miR-101-3p.

Conclusions

Our data illustrate how SPRY4-IT1 plays an oncogenic role in CCA and may offer a potential therapeutic target for treating CCA.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0747-x) contains supplementary material, which is available to authorized users.