BRAF-activated LncRNA functions as a tumor suppressor in papillary thyroid cancer

Long Noncoding RNA CAMTA1 Promotes Proliferation and Mobility of the Human Breast Cancer Cell Line MDA-MB-231 via Targeting miR-20b

Breast cancer is a serious threat to women's physical and psychological health. Long noncoding RNA CAMTA1 (lncCAMTA1) was believed to be related with tumor progression, but its role in breast cancer is not clear. The human breast cancer cell line MDA-MB-231 was used to investigate the effect of lncCAMTA1 on cell viability, migration/invasion, and apoptosis. The expression of lncCAMTA1, miR-20b, and VEGF in MDA-MB-231 were measured after corresponding transfections. Binding effects between lncCAMTA1 and miR-20b, miR-20b, and VEGF 3'-UTR were measured. The effects of miR-20b and VEGF on breast cancer cells were also assessed after transfections. The phosphorylation levels of the MAPK/ERK and JAK/STAT3 pathways were determined to assess the effect of VEGF. The results showed that lncCAMTA1 expression promoted cell viability and migration/invasion, while knockdown of lncCAMTA1 promoted cell apoptosis via binding with miR-20b. lncCAMTA1 negatively regulated miR-20b expression. VEGF was a target of miR-20b, leading to the modification of the phosphorylation levels of MAPK, ERK, JAK, STAT1, and STAT3. Our findings suggested that lncCAMTA1 might promote proliferation and mobility of human breast cancer cells via binding with miR-20b. VEGF was a direct target of miR-20b and regulated activation of the MAPK/ERK and JAK/STAT3 signaling pathways. Therefore lncCAMTA1 has potential as a novel cancer diagnostic marker and as a putative novel therapeutic target for breast cancer treatment.

Downregulation of BANCR Promotes Aggressiveness in Papillary Thyroid Cancer via the MAPK and PI3K Pathways

Recent evidence indicates that long non-coding RNAs play important roles in tumorigenesis and cancer progression. BRAF-activated non-protein coding RNA (BANCR) is a novel and potential regulator of cancer cell proliferation and migration. However, little is known regarding the role of BANCR in papillary thyroid cancer (PTC). The current study used quantitative PCR to demonstrate that BANCR was significantly downregulated in 60 paired PTC tissues compared with normal tissues. In addition, BANCR was significantly correlated with lymph node metastasis (p = 0.02). Furthermore, Cell Counting Kits and Transwell assays were used to demonstrate that knocking down BANCR with short hairpin RNA (shRNA) transfection significantly promoted the proliferation and invasion of PTC cell lines. The flow cytometric analysis of apoptosis and the cell cycle revealed that the overexpression of BANCR inhibited cancer cell proliferation and invasion, which was associated with the induction of cell-cycle G2/M phase arrest and increased apoptosis. Moreover, western blotting was used to show that the MAPK and PI3K-Akt pathways were aberrantly activated during BANCR-mediated PTC cell proliferation and migration. These findings revealed that BANCR functions as a tumor suppressor during thyroid carcinogenesis.

Role of lncRNAs in the cancer development and progression and their regulation by various phytochemicals

Long non coding RNAs (lncRNAs) are involved in modulating the expression of other non-coding RNAs (ncRNA), such as microRNAs, or target proteins through the epigenetic, transcriptional, or post-transcriptional regulations. Genomic mutations in cancer reside inside regions that do not code for proteins and these regions are often transcribed into long non coding RNAs (lncRNAs). Emerging evidences have revealed an intense involvement of lncRNAs in the cancer development and progression. Recently, emerging evidences have depicted that the phytochemicals interact with lncRNAs to modulate their activities. Such findings are highly important for the identification of therapeutic strategies against diseases that are particularly associated with an aberrant lncRNA signaling. This review aims at deciphering the role of lncRNAs in the cancer development and progression, and their regulation by various phytochemicals.

The BRAF activated non-coding RNA: A pivotal long non-coding RNA in human malignancies

Long non-coding RNAs (lncRNAs) participate in the complex network of cancer and play an important role in tumourigenesis and progression. BRAF activated non-coding RNA (BANCR), a 4-exon transcript of 693-bp, was first discovered as an oncogenic long non-coding RNA in BRAF^V600E melanomas cells in 2012 and was related to melanoma cell migration. Besides melanoma, increasing evidence has explored the potential role of BANCR in the development and progression of multiple other human malignancies, such as retinoblastoma, lung cancer, gastric cancer etc. since its discovery. The expression pattern of BANCR varies in different types of cancers, either as a tumour suppressor or as an accelerator. Functional BANCR may serve as a promising biomarker for cancer diagnosis as well as prognosis evaluation. BANCR-targeted intervention may also become a valuable novel therapeutic tool against human malignancies. This review summarized the advanced research progresses concerning the expression and role of BANCR in different human malignancies.

BRAF-activated lncRNA predicts gastrointestinal cancer patient prognosis: a meta-analysis

BRAF activated non-coding RNA (BANCR) is often dysregulated in cancer. We performed a meta-analysis to clarify its functions as a prognostic indicator in malignant tumors. We searched the PubMed, Medline, OVID, Cochrane Library, and Web of Science databases to identify BANCR-related studies. Nine original studies and 898 total patients were included in the meta-analysis. Hazard ratios (HR) and 95% confidence intervals (CI) were extracted from the included studies to determine the relationship between BANCR expression and patient overall survival (OS). Odds ratios (OR) were calculated using RevMan 5.3 software to assess associations between BANCR expression and pathological parameters. High BANCR expression correlated with lymph node metastasis (LNM) (OR = 3.41, 95% CI: 1.82-6.37, P = 0.0001), distant metastasis (DM) (OR = 2.98, 95% CI: 1.76-5.07, P < 0.0001), tumor stage (OR = 3.11, 95% CI: 1.89-5.12, Z = 3.25, P < 0.0001), and poor OS (pooled HR = 1.98, 95% CI: 1.20-3.27, P = 0.008) in gastrointestinal (GI) cancer patients, but not in non-GI cancer patients. Our results support the notion that BANCR as a promising prognostic biomarker in Chinese patients with GI cancer.

Long noncoding RNAs: emerging players in thyroid cancer pathogenesis

Thyroid cancer continues to be the most common malignancy of endocrine glands. The incidence of thyroid cancer has risen significantly over the past 4 decades and has emerged as a major health issue. In recent years, significant progress has been achieved in our understanding of the molecular mechanisms of thyroid carcinogenesis, resulting in significant diagnostic, prognostic and therapeutic implications; yet, it has not reached a satisfactory level. Identifying novel molecular therapeutic targets and molecules for diagnosis and prognosis is expected to advance the overall management of this common malignancy. Long noncoding RNAs (lncRNAs) are implicated in the regulation of various key cellular genes involved in cell differentiation, proliferation, cell cycle, apoptosis, migration and invasion mainly through modulation of gene expression. Recent studies have established that lncRNAs are deregulated in thyroid cancer. In this review, we discuss extensively the tumor-suppressive (for example, LINC00271, MEG3, NAMA, PTCSC1/2/3, etc.) and oncogenic (for example, ANRIL, FAL1, H19, PVT1, etc.) roles of various lncRNAs and their possible disease associations implicated in thyroid carcinogenesis. We briefly summarize the strategies and mechanisms of lncRNA-targeting agents. We also describe the potential role of lncRNAs as prospective novel therapeutic targets, and diagnostic and prognostic markers in thyroid cancer.

Current research on head and neck cancer-associated long noncoding RNAs

Head and neck cancers (HNC) are one of the ten leading cancers worldwide, including a range of malignant tumors arising from the upper neck. Due to the complex mechanisms of HNC and lack of effective biomarkers, the 5-year survival rate of HNC has been low and the mortality rate has been high in recent decades. Long noncoding RNAs (lncRNAs), noncoding RNAs longer than 200 bps, are a focus of current cancer research, closely related to tumor biology. LncRNAs have been revealed to be aberrantly expressed in various types of HNC, and the dysregulated lncRNAs participate in HNC progression and induce malignant behavior by modulating gene expression at diverse levels. This review will focus on the functions and molecular mechanisms of dysregulated lncRNAs in HNC tumorigenesis and progression, as well as their diagnostic, therapeutic or prognostic implications in HNC.

Long noncoding RNA CNALPTC1 promotes cell proliferation and migration of papillary thyroid cancer via sponging miR-30 family

Several somatic copy number variations (CNVs) have been identified in papillary thyroid cancer (PTC). However, the functional roles of CNVs and the genes responsible for the roles of CNVs are largely unknown. In this study, we identified a novel long noncoding RNA (lncRNA) CNALPTC1 (copy number amplified long noncoding RNA in papillary thyroid cancer 1). The genomic copy number of CNALPTC1 is amplified and CNALPTC1 expression level is up-regulated in PTC. Increased expression of CNALPTC1 is associated with aggressive clinicopathological characteristics. Gain-of-function and loss-of-function assays revealed that CNALPTC1 promotes proliferation and migration of PTC cells, and inhibits apoptosis of PTC cells. Mechanistically, we found that CNALPTC1 physically associates to miR-30 family and down-regulates miR-30 expression. Furthermore, CNALPTC1 up-regulates the expression of miR-30 targets, such as BCL9, SNAI1, and VIM. The mutation of miR-30 binding site on CNALPTC1 or overexpression of miR-30 abrogates the oncogenic roles of CNALPTC1 in PTC. Collectively, our results suggested that the copy number amplified lncRNA CNALPTC1 promotes PTC progression via sponging miR-30 family. Our data also implied that CNALPTC1 may be a novel therapeutic target for PTC.

Long non-coding RNA cartilage injury-related promotes malignancy in bladder cancer

Recent advances have highlighted the important roles of long non-coding RNAs (lncRNAs) in a number of biological processes, including oncogenesis. However, the function of lncRNA cartilage injury-related (lncRNA-CIR) in bladder cancer progression remains elusive. A novel function for lncRNA-CIR in bladder cancer was identified in the present study. Reverse transcription quantitative polymerase chain reaction, viability, invasion assay and in vivo implantation were used to evaluate the role of lncRNA-CIR. It was identified that the expression of lncRNA-CIR was frequently upregulated in 52 cancerous tissues and selected bladder cancer cell lines. Additionally, upregulating lncRNA-CIR was demonstrated to promote viability and invasion in T24 and SW780 cells, whereas siRNA-mediated lncRNA-CIR-knockdown consistently exhibited the opposite effects. High lncRNA-CIR levels also dictated poor overall survival among patients with bladder cancer. Furthermore, in vivo implantation experiments also supported a tumorigenic function for lncRNA-CIR, as decreasing lncRNA-CIR levels markedly attenuated Ki-67 staining and xenograft tumor growth. Overall, the present study identified a novel function of lncRNA-CIR and indicates that lncRNA-CIR may serve as a potential biomarker for bladder cancer treatment.

LncRNA MEG3 ameliorates respiratory syncytial virus infection by suppressing TLR4 signaling

Maternally expressed gene 3 (MEG3), a long noncoding RNA (lncRNA) has been dysregulated in various tumors. However, the expression level and functional role of MEG3 in the progression of respiratory syncytial virus (RSV) infection remains to be elucidated. The present study quantified the expression level of MEG3 in the nasopharyngeal (NPA) samples of RSV‑infected patients and in BEAS‑2B cells infected with RSV. The findings of the present study demonstrated that the expression level of lncRNA MEG3 was reduced in the NPA samples of RSV‑infected patients and in BEAS‑2B cells infected with RSV. In vitro transfection revealed increased mRNA expression levels of toll‑like receptor 4 (TLR4), tumor necrosis factor‑α (TNFα) and interleukin (IL)‑8 following RSV infection in BEAS‑2B cells. Additionally, ectopic expression of MEG3 reduced the expression level of TLR4, subsequently suppressing the mRNA expression levels of TNFα and IL‑8, indicating the protective role of MEG3 in the process of RSV infection. It is of note, that RSV infection‑induced p38 mitogen activated protein kinase (MAPK) and nuclear factor‑κB (NF‑κB) activation was partly abolished by overexpression of MEG3. In conclusion, to the best of our knowledge, the present study provided the first evidence that lncRNA MEG3 expression level was reduced in the NPA samples of patients with RSV infection and RSV‑infected cells. Additionally, it was demonstrated that MEG3 protected human airway epithelial cells from RSV infection, primarily by suppressing TLR4‑dependent p38 MAPK and NF‑κB signaling.

Prognostic Role of Long Noncoding RNA BANCR in Solid Tumors: A Meta-Analysis

Accumulating studies have reported that long noncoding RNA BRAF-activated nonprotein coding RNA plays vital role in various cancers. However, the prognostic values of BRAF-activated nonprotein coding RNA in solid tumors remain controversial. Thus, we assessed the prognostic values of BRAF-activated nonprotein coding RNA by this meta-analysis. We comprehensively searched PubMed, Web of Science, Medline, China National Knowledge Infrastructure (CNKI), and the Cochrane Library at November 2016. After carefully screening, we ultimately included 14 studies in this meta-analysis. This meta-analysis brought all relevant articles into determining the association of BRAF-activated nonprotein coding RNA expression with overall survival and clinicopathologic features. The results showed that high BRAF-activated nonprotein coding RNA expression significantly shorten the overall survival of solid tumors (pooled hazard ratios 1.66, 95% confidence interval: 1.19-2.32). Moreover, high BRAF-activated nonprotein coding RNA expression was also strongly associated with advanced tumor stage (odds ratios = 2.57, 95% confidence interval: 1.14-5.79), differentiation grade (odds ratio = 1.71, 95% confidence interval: 1.26-2.31), lymph node metastasis (odds ratio = 2.67, 95% confidence interval: 1.93-3.70, P < .001), and distant metastasis (odds ratio = 2.98, 95% confidence interval: 1.76-5.07, P = .02). In conclusion, this meta-analysis demonstrated that high BRAF-activated nonprotein coding RNA expression may be a potential novel biomarker for indicating a poor prognosis and progression in human solid tumors.

RNA-sequencing investigation identifies an effective risk score generated by three novel lncRNAs for the survival of papillary thyroid cancer patients

Scholars are striving to apply molecular biology involving long non-coding RNA (lncRNA) in the prognostication of papillary thyroid cancer (PTC). However, the clinical role of lncRNAs in the prognostic setting of PTC is still unclear. Herein, a comprehensive inquiry was performed to screen lncRNA expression profiling with 507 PTC patients from The Cancer Genome Atlas RNA-sequencing datasets. A total of 734 lncRNAs were detected to be aberrantly expressed, among which three novel lncRNAs including AC079630.2, CRNDE and CTD-2171N6.1 were markedly related to the progression and survival of PTC. Furthermore, the aberrant expression of these lncRNAs could be verified by other cohorts from gene expression omnibus (GEO) as detected by microarrays. Next, we established a three-lncRNA signature and divided the PTC patients into two subgroups of high- and low-risk. Interestingly, patients with high-risk tended to gain obviously poorer outcome. Most importantly, this three-lncRNA signature was an independent biomarker to predict the patient survival of PTC. The accurate molecular roles of these three lncRNAs remains unclarified and warrants further characterization, but our current data propose that they might play pivotal roles in PTC tumorigenesis and more importantly, these novel lncRNAs are closely related to patients' survival. These discoveries will have far-reaching consequences with respect to molecular prediction of PTC.

LncRNA SNHG1 enhances cell proliferation, migration, and invasion in cervical cancer

OBJECTIVE

This study investigated the effects of lncRNA SNHG1 on the proliferation, migration, and invasiveness of cervical cancer cells.

METHODS

Three pairs of cervical cancer tissue samples and their corresponding adjacent samples were analyzed using Human LncRNA Microarray V3.0 chip for differential analysis. The expression of SNHG1 in cervical cancer cell lines was verified by qRT-PCR. CCK8 assays and colony formation assays were used to study the changes in cell proliferation. Cell migration and Transwell assays were used to study changes in cell migration and invasiveness.

RESULTS

SNHG1 was highly expressed in cervical cancer tissues and cervical cancer cell lines. SNHG1 siRNA could knock-down the expression level of SNHG1 in cervical cancer cell lines HeLa and C33-A. After knock-down of SNHG1, cell proliferation and migration as well as invasiveness in HeLa and C-33A cells decreased.

CONCLUSION

LncRNA SNHG1 promotes the development of cervical cancer cells.

Long Non-Coding RNAs: Key Regulators of Epithelial-Mesenchymal Transition, Tumour Drug Resistance and Cancer Stem Cells

Epithelial mesenchymal transition (EMT), the adoption by epithelial cells of a mesenchymal-like phenotype, is a process co-opted by carcinoma cells in order to initiate invasion and metastasis. In addition, it is becoming clear that is instrumental to both the development of drug resistance by tumour cells and in the generation and maintenance of cancer stem cells. EMT is thus a pivotal process during tumour progression and poses a major barrier to the successful treatment of cancer. Non-coding RNAs (ncRNA) often utilize epigenetic programs to regulate both gene expression and chromatin structure. One type of ncRNA, called long non-coding RNAs (lncRNAs), has become increasingly recognized as being both highly dysregulated in cancer and to play a variety of different roles in tumourigenesis. Indeed, over the last few years, lncRNAs have rapidly emerged as key regulators of EMT in cancer. In this review, we discuss the lncRNAs that have been associated with the EMT process in cancer and the variety of molecular mechanisms and signalling pathways through which they regulate EMT, and finally discuss how these EMT-regulating lncRNAs impact on both anti-cancer drug resistance and the cancer stem cell phenotype.

H19 promotes the migration and invasion of colon cancer by sponging miR-138 to upregulate the expression of HMGA1

Colon cancer is the most common digestive system malignancy, along with high mortality rate, familial transmissibility and hepatic metastasis. Our study investigated the role of long non-coding RNA H19 in colon cancer. We found that H19 was overexpressed in colon cancer tissues and cell lines, the interference of H19 by short hairpin RNA (shRNA) effectively decreased the migration and invasion of colon cancer cells (HT-29 and RKO). Besides, miR-138 was predicted a target of H19, and low expression of miR-138 was found in colon cancer tissues and cells. The silence of H19 strongly increased the expression of miR-138. The decreased level of miR-138 was elevated adding miR-138 mimic in RKO cells transfected with lncRNA-H19. Similarly, the upregulated level of miR-138 was downregulated adding miR-138 inhibitor in RKO cells transfected with H19 shRNA. The luciferase reporter confirmed the targeting reaction between H19 and miR-138. Moreover, the high-mobility group A (HMGA1) protein was predicted as a target of miR-138. HMGA1 was suppressed by H19 shRNA and could be up-regulated by miR-138 inhibitor. The migration and invasion ability of colon cancer was restrained by H19 shRNA and promoted by miR-138 inhibitor. Finally, the in vivo experiment revealed that H19 shRNA strongly reduced the tumor growth and tumor volume. H19 shRNA also inhibited metastasis via suppressing hepatic metastases and the expression of metastasis-related proteins. Taken together, our research indicated an H19-miR138-HMGA1 pathway in regulating the migration and invasion of colon cancer, providing new insight for treatment of colon cancer.

Comprehensive analysis of long noncoding RNA–mRNA co-expression patterns in thyroid cancer

Novel molecular-targeted treatments show great prospects for radioiodine-refractory and surgically inoperable thyroid carcinomas.