High Expression of the Newly Found Long Noncoding RNA Z38 Promotes Cell Proliferation and Oncogenic Activity in Breast Cancer

Regulation and Therapeutic Application of Long non-Coding RNA in Tumor Angiogenesis

Tumor growth and metastasis rely on angiogenesis. In recent years, long non-coding RNAs have been shown to play an important role in regulating tumor angiogenesis. Here, we review the multidimensional modes and relevant molecular mechanisms of long non-coding RNAs in regulating tumor angiogenesis. In addition, we summarize new strategies for tumor anti-angiogenesis therapies by targeting long non-coding RNAs. The aim of this study is to provide new diagnostic targets and treatment strategies for anti-angiogenic tumor therapy.

KGLRR: A low-rank representation K-means with graph regularization constraint method for Single-cell type identification

Single-cell RNA sequencing technology provides a tremendous opportunity for studying disease mechanisms at the single-cell level. Cell type identification is a key step in the research of disease mechanisms. Many clustering algorithms have been proposed to identify cell types. Most clustering algorithms perform similarity calculation before cell clustering. Because clustering and similarity calculation are independent, a low-rank matrix obtained only by similarity calculation may be unable to fully reveal the patterns in single-cell data. In this study, to capture accurate single-cell clustering information, we propose a novel method based on a low-rank representation model, called KGLRR, that combines the low-rank representation approach with K-means clustering. The cluster centroid is updated as the cell dimension decreases to better from new clusters and improve the quality of clustering information. In addition, the low-rank representation model ignores local geometric information, so the graph regularization constraint is introduced. KGLRR is tested on both simulated and real single-cell datasets to validate the effectiveness of the new method. The experimental results show that KGLRR is more robust and accurate in cell type identification than other advanced algorithms.

Molecular regulation of hypoxia through the lenses of noncoding RNAs and epitranscriptome

Cells maintain homeostasis in response to environmental stress through specific cell stress responses. Hypoxic stress, well known to be associated with diverse solid tumors, is one of the main reasons for cancer-related mortality. Although cells can balance themselves well during hypoxic stress, the underlying molecular mechanisms are not well understood. The enhanced appreciation of diverse roles played by noncoding transcriptome and epigenome in recent years has brought to light the involvement of noncoding RNAs and epigenetic modifiers in hypoxic regulation. The emergence of techniques like deep sequencing has facilitated the identification of large numbers of long noncoding RNAs (lncRNAs) that are differentially regulated in various cancers. Similarly, proteomic studies have identified diverse epigenetic modifiers such as HATs, HDACs, DNMTs, polycomb groups of proteins, and their possible roles in the regulation of hypoxia. The crosstalk between lncRNAs and epigenetic modifiers play a pivotal role in hypoxia-induced cancer initiation and progression. Besides the lncRNAs, several other noncoding RNAs like circular RNAs, miRNAs, and so forth are also expressed during hypoxic conditions. Hypoxia has a profound effect on the expression of noncoding RNAs and epigenetic modifiers. Conversely, noncoding RNAs/epigenetic modifies can regulate the hypoxia signaling axis by modulating the stability of the hypoxia-inducible factors (HIFs). The focus of this review is to illustrate the molecular orchestration underlying hypoxia biology, especially in cancers, which can help in identifying promising therapeutic targets in hypoxia-induced cancers. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA in Disease and Development > RNA in Disease RNA Structure and Dynamics > RNA Structure, Dynamics and Chemistry.

Circulating LncRNAs landscape as potential biomarkers in breast cancer

BACKGROUND

In Iran, the delay in diagnosis and treatment of breast cancer results in low survival rates.

AIM

It is essential to characterize new therapeutic targets and prognostic breast cancer biomarkers. The rising evidence suggested that long non-coding RNAs (lncRNAs) expression levels are deregulated in human cancers and can use as biomarkers for the rapid diagnosis of breast cancer.

METHODS

In the present study, a quantitative real-time polymerase chain reaction (qRT-PCR) technique was used to measure 20 oncogenic and tumor suppressor lncRNAs expression levels in whole blood samples of female breast cancer patients and healthy women. Receiver operating characteristic curve (ROC) was used to assess the diagnostic value of each selected lncRNA as a biomarker.

RESULTS

The results revealed that some circulating lncRNAs (MEG3, NBAT1, NKILA, GAS5, EPB41L4A-AS2, Z38, and BC040587) were significantly down-regulated in breast cancer patients compared to healthy women. In contrast, other circulating lncRNAs (H19, SPRY4-IT1, XIST, UCA1, AC026904.1, CCAT1, CCAT2, ITGB2-AS, and AK058003) were significantly up-regulated in breast cancer patients compared to controls. It was shown that the expression levels of NKILA, and NBAT1 lncRNAs were related to tumor size, and BC040587 expression level related to age, node metastasis, tumor size, and grade (p < .05). The association between H19 and SPRY4-IT1 lncRNAs with HER-2 was confirmed statistically (p < .05). ROC curves illustrated that the blood levels of SPRY4-IT1, XIST, and H19 lncRNAs have excellent potential in discriminating breast cancer from the healthy controls, showing an AUC of 1.0 (95% CI 1.0-1.0, p = .00), 0.898 (95% CI 0.815-0.981, p = .00), and 0.848 (95% CI 0.701-0.995, p = .01), respectively.

CONCLUSION

In conclusion, the expression levels of circulating H19 and SPRY4-IT1 lncRNAs in breast cancer patients could consider as the prognostic biomarkers and therapeutic targets in breast cancer, because of their excellent power in discriminating breast cancer from healthy individuals and the significant correlation of H19, and SPRY4-IT1 lncRNAs with clinicopathological traits. We also suggest the possible application of BC040587 lncRNA as a diagnostic and prognostic indicator to assess tumor progression in case of verification in larger patients' cohorts.

Coding roles of long non-coding RNAs in breast cancer: Emerging molecular diagnostic biomarkers and potential therapeutic targets with special reference to chemotherapy resistance

Dysregulation of epigenetic mechanisms have been depicted in several pathological consequence such as cancer. Different modes of epigenetic regulation (DNA methylation (hypomethylation or hypermethylation of promotor), histone modifications, abnormal expression of microRNAs (miRNAs), long non-coding RNAs, and small nucleolar RNAs), are discovered. Particularly, lncRNAs are known to exert pivot roles in different types of cancer including breast cancer. LncRNAs with oncogenic and tumour suppressive potential are reported. Differentially expressed lncRNAs contribute a remarkable role in the development of primary and acquired resistance for radiotherapy, endocrine therapy, immunotherapy, and targeted therapy. A wide range of molecular subtype specific lncRNAs have been assessed in breast cancer research. A number of studies have also shown that lncRNAs may be clinically used as non-invasive diagnostic biomarkers for early detection of breast cancer. Such molecular biomarkers have also been found in cancer stem cells of breast tumours. The objectives of the present review are to summarize the important roles of oncogenic and tumour suppressive lncRNAs for the early diagnosis of breast cancer, metastatic potential, and chemotherapy resistance across the molecular subtypes.

LncRNA TTN-AS1 confers tamoxifen resistance in breast cancer via sponging miR-107 to modulate PI3K/AKT signaling pathway

OBJECTIVE

Tamoxifen resistance of breast cancer (BC) is a significant hindrance in clinical therapy. The long-noncoding RNA (lncRNA) TTN-AS1 has been reported as a crucial tumor promoting factor in various cancers. In this study, we set out to discover the specific pathologic regulatory mechanisms of tamoxifen-resistance in breast cancer.

METHODS

MTT assay was conducted to evaluate the cell viability of the breast cancer cell lines MCF-7 and MCF-7/TAM. QRT-PCR and western blot assay were performed to estimate the expression of TTN-AS1, miR-107 and related proteins. Flow cytometry was conducted to identify degree of apoptosis and cell cycle. The invasive ability was estimated by transwell chamber assay.

RESULTS

Our findings revealed that TTN-AS1 can enhance tamoxifen-resistance in BC cells and augment the invasive ability of tamoxifen-resistant breast cancer cells by down-regulating miR-107, and thereby encourage the development of drug-resistant BC. Further investigation indicates that lncRNA TTN-AS1 worsens the course of tamoxifen-resistant BC by regulating zinc and ring finger 2 (ZNRF2) via miR-107 and activating the PI3K/AKT pathway.

CONCLUSION

Our findings suggest that the lncRNA TTN-AS1 can encourage tamoxifen-resistance in BC by modulating the miR-107/ZNRF2 axis and stimulating the PI3K/AKT pathway.

Systematic identification and characterization of long noncoding RNAs (lncRNAs) during Aedes albopictus development

Background

Aedes albopictus originated in the tropical forests of Southeast Asia and can currently be found on all continents. As one of the main arboviral vectors, the control of Ae. albopictus requires novel strategies, informed by a deep knowledge of its biology. Little is known regarding mosquito long noncoding RNAs (lncRNAs), which are transcripts longer than 200 nucleotides that lack protein-coding potential and have roles in developmental regulation.

Results

Based on RNA-seq data from five developmental time points, eggs, early larvae, late larvae, pupae, and adults (female and male) of Ae. albopictus, 21,414 lncRNAs were characterized in this study. Differential expression analysis revealed that lncRNAs exhibited developmental stage specificity. The expression of most lncRNAs was upregulated at the onset of metamorphosis developmental stages. More differentially expressed lncRNAs were observed between eggs and early larvae. Weighted gene co-expression network analysis (WGCNA) further confirmed that the expression patterns of lncRNAs were obviously correlated with specific developmental time points. Functional annotation using co-expression analysis revealed that lncRNAs may be involved in the regulation of metamorphic developmental transitions of Ae. albopictus. The hub lncRNAs and hub gene clusters were identified for each module that were highly associated with specific developmental time points.

Conclusions

The results of this study will facilitate future researches to elucidate the regulatory mechanisms of lncRNAs in the development of Ae. albopictus and utilize lncRNAs to assist with mosquito control.

LncRNA SUMO1P3 acts as a prognostic biomarker and promotes hepatocellular carcinoma growth and metastasis

Long noncoding RNAs (lncRNAs) are involved in the progression of various cancers, including hepatocellular carcinoma (HCC). However, the biological functions of lncRNA small ubiquitin-like modifier 1 pseudogene 3 (SUMO1P3) and the underlying mechanisms remain unclear. In this study, we revealed that SUMO1P3 expression was enhanced in HCC tissues and cell lines, positively associating with tumor size and number, poor differentiation, lymphatic and distant metastasis, TNM stage, and poor prognosis in HCC patients. In vitro assays showed that SUMO1P3 depletion reduced HCC cell viability and proliferation by hindering cyclin D1 expression and Akt phosphorylation. SUMO1P3 knockdown induced HCC cell apoptosis, as indicated by increased Bax and cleaved caspase-3 expression and the decreased Bcl-2 level. SUMO1P3 silencing suppressed HCC cell migration and invasion by increasing epithelial marker E-cadherin expression and decreasing mesenchymal marker vimentin expression, as well as reducing matrix metalloproteinase (MMP)-2 and MMP-9 levels. Consistently, SUMO1P3 depletion in HCC cells retarded tumor growth and lung metastasis in vivo. Overall, these results supported the applicability of SUMO1P3 as a useful predictor of HCC prognosis and a potential therapeutic target for HCC patients.

LncRNAs as Architects in Cancer Biomarkers with Interface of Epitranscriptomics- Incipient Targets in Cancer Therapy

Long non-coding RNAs (LncRNAs) epitomize a class of non-coding regulatory RNAs with more than 200 nucleotides, which are long and situated in the nucleus or cytoplasm and rarely encode proteins. Accruing evidence signposts that lncRNAs act as molecular switches in different cellular activities like differentiation, apoptosis, as well as reprogramming of cellular states by modifying gene expression patterns. The revelation of immense numbers of lncRNA with their wide variety of expression patterns in different kinds of malignancy, tumor explicitness, and their steadiness in circulating body fluids deliver an innovative groundwork for emerging diagnosis and treatments for cancer. Mechanisms associating lncRNAs in carcinogenesis are conquered by deregulation of cellular signaling pathways and altered epitranscriptome along with their expression. Specified these attributes, it becomes clear that the improvement of new tools to identify lncRNAs with higher affectability will be fundamental to allow the identification of the expression pattern of lncRNAs in various kinds of malignant growth and may likewise be utilized to envisage cancer prognosis in addition to the patients' outcome. Improvement of RNA targeting-based therapeutics is delivering incredible prospects to modulate lncRNAs for anti-cancer initiatives. Henceforth, lncRNAs can be used exclusively as possible cancer biomarkers for early diagnosis and anticipation of malignancy, as well as metastasis. In addition to the basic curative targets and along these, lncRNAs hold resilient assurance towards the revelation of innovative diagnostics and therapeutics for malignant growth with the interface of epitranscriptomics information. This review aims to briefly discuss the latest findings regarding the roles and mechanisms of some important lncRNAs in the pathogenesis, regulation, and lncRNA-associated epigenetics of cancer along with targeting lncRNAs with potential approaches for impending diagnosis and therapeutic intervention in malignancies.

The relationship between Long Noncoding RNA (lncRNA) Small Nucleolar RNA Host Gene 12 (SNHG12) expression in solid malignant tumors and prognosis of tumor patients: A systematic review and meta-analysis

BACKGROUND

Small nucleolar RNA host gene 12 (SNHG12) has been demonstrated to be a long noncoding RNA (lncRNA) that facilitates the progression of several solid malignant tumors. However, whether the expression level of SNHG12 in solid malignant tumors is associated with patients prognosis have not been investigated.

METHODS

We systematically searched PubMed, EMBASE and Cochrane Library from Jan 1, 1950 to Mar 24, 2020 for randomized controlled trials published in English on SNHG12 expression in solid malignant tumors. We used the Newcastle-Ottawa Scale to assess the quality of articles. The HRs and 95%CI that extracted from Kaplan-Meier curves were used to perform the forest plot using a fixed-effects model. The meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Thirteen articles containing 821 patients were included in this systematic review and meta-analysis. The result showed that high lncRNA SNHG12 expression is significantly associated with poor overall survival (OS) (HR = 1.94, 95% CI: 1.56-2.41, P < .001) and the studies are lack of statistically significant heterogeneity (P= .878, I = 0.0%). Beggs plot and Eggers test were applied to testify no publication bias existence in these studies. Subgroup analyses were performed and the result showed that TNM stage, lymph node metastasis and tumor type can influence the patients outcome, while there was no significantly correlation between SNHG12 expression and gender.

CONCLUSIONS

The systematical review and meta-analysis synthetically analyzed 13 articles including 821 patients with ten types of solid malignant tumors, concluding that higher lncRNA SNHG12 expression is significantly associated with worse clinical prognosis.

Long non-coding RNA regulation of TRAIL in breast cancer: A tangle of non-coding threads

Breast cancer is a complex disease posing a serious threat to the female population worldwide. A complex molecular landscape and tumor heterogeneity render breast cancer cells resistant to drugs and able to promote metastasis and invasiveness. Despite the recent advancements in diagnostics and drug discovery, finding an effective cure for breast cancer is still a major challenge. Positive and negative regulation of apoptosis has been a subject of extensive study over the years. Numerous studies have shed light on the mechanisms that impede the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) signaling cascade. Long non-coding RNAs (lncRNAs) have been implicated in the orchestration, development, proliferation, differentiation and metastasis of breast cancer. However, the roles of lncRNAs in fine-tuning apoptosis regulating machinery in breast cancer remain to be elucidated. The present review illuminates the roles of these molecules in the regulation of breast cancer and the interplay between lncRNA and TRAIL in breast cancer. The present review also attempts to reveal their role in the regulation of apoptosis in breast cancer appears a promising approach for the development of new diagnostic and therapeutic regimens.

Hypermethylation of lncRNA MEG3 impairs chemosensitivity of breast cancer cells

Background

Chemoresistance posed a barrier to successful treatment of breast cancer (BC), and lncRNA MEG3 has been documented to implicate in BC development. However, whether MEG3 methylation, which led to low MEG3 expression, was relevant to BC progression and chemoresistance remained uncertain.

Methods

In the aggregate, 374 pairs of tumor tissues and adjacent normal tissues were collected from pathologically confirmed BC patients, and four BC cell lines, including MDA‐MB‐231, Bcap‐37, MCF‐7, and SK‐BR‐3, were purchased. Moreover, methylation‐specific polymerase chain reaction (PCR) was adopted to evaluate the methylation status of BC tissues and cell lines, and chemo‐tolerance of BC cell lines was assessed by performing MTT assay. Concurrently, transwell assay and scratch assay were carried out to estimate the migratory and invasive capability of BC cell lines.

Results

Methylated MEG3, lowly expressed MEG3, large tumor size (≥2 cm), advanced TNM grade and lymphatic metastasis were potentially symbolic of poor prognosis among BC patients (P < .05). Besides, MDA‐MB‐231 cell line exhibited the strongest resistance against paclitaxel, adriamycin, and vinorelbine (P < .05), while MCF‐7 cell line seemed more sensitive against these drugs than any other BC cell line (P < .05). Furthermore, pcDNA3.1‐MEG3 and 5‐Aza‐dC markedly sensitized MDA‐MB‐231 and MCF‐7 cell lines against the drug treatments (P < .05). Simultaneously, proliferation and metastasis of the BC cell lines were slowed down under the force of pcDNA3.1‐MEG3 and 5‐Aza‐dC (P < .05).

Conclusion

Preventing methylation of MEG3 might matter in lessening BC chemoresistance, owing to its hindering proliferation and metastasis of BC cells.

LncRNA MIR4435-2HG triggers ovarian cancer progression by regulating miR-128-3p/CKD14 axis

Background

Accumulating studies showed that long noncoding RNAs (lncRNAs) played vital roles in cancer progression. LncRNA MIR4435-2HG was proved to act as an oncogene in various tumors. However, the underlying function of MIR4435-2HG in ovarian cancer (OC) remains unclear.

Methods

The expression levels of MIR4435-2HG, miR-128-3p and cyclin-dependent kinase 14 (CDK14) were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation and apoptosis in OC cells were detected by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis, respectively. Transwell assay was applied to evaluate cell migration and invasion. Wound healing assay was performed to monitor the migration rate. Western blot assay was performed to detect the protein levels of Bcl-2, Cleaved PARP, E-cadherin, Vimentin and CDK14 in OC cells. The binding sites between miR-128-3p and MIR4435-2HG or CDK14 were predicted by online tool starBase and their relationship was confirmed by dual-luciferase reporter assay, RIP assay and pull-down experiment.

Results

MIR4435-2HG and CDK14 were over-expressed in OC tissues and cells. Patients with high MIR4435-2HG expression had poorer overall survival (OS) than patients with low MIR4435-2HG expression. MIR4435-2HG knockdown inhibited proliferation, invasion and migration but induced apoptosis of OC cells via miR-128-3p/CDK14 axis. In conclusion, MIR4435-2HG knockdown suppressed the progression of OC cells through downregulating CDK14 expression by the promotion of miR-128-3p.

Critical roles of long noncoding RNAs in breast cancer

Breast cancer is a major clinical challenge that affects a wide range of the female population and heavily burdens the health system. In the past few decades, attempts have been made to understand the etiology of breast cancer, possible environmental risk factors, and the genetic predispositions, pathogenesis, and molecular aberrations involved in the process. Studies have shown that breast cancer is a heterogeneous entity; each subtype has its specific set of aberrations in different cell signaling pathways, such as Notch, Wnt/β-catenin, transforming growth factor-β, and mitogen-activated protein kinase pathways. One novel group of molecules that have been shown to be inducted in the regulation of multiple cell signaling pathways is the long noncoding RNAs (lncRNAs). These molecules have important implications in the regulation of multiple signaling pathways by interacting with various genes, affecting the transcription process, and finally, playing roles in posttranslational control of these genes. There is growing evidence that lncRNAs are involved in the process of breast cancer formation by effecting the aforementioned signaling pathways, and that this involvement can have significant diagnostic and prognostic values in clinical contexts. The present review aims to elicit the significance of lncRNAs in the regulation of cell signaling pathways, and the resulting changes in cell survival, proliferation, and invasion, which are the hallmarks of breast cancer.

Role of long non-coding RNAs in lymphoma: A systematic review and clinical perspectives

Long non-coding RNAs (lncRNAs), are over 200 nucleotides in length, and they rarely act as templates for protein synthesis. Mounting studies have shown that lncRNAs play a crucial regulatory role in various processes that sustain life, such as epigenetic regulation, cell cycle control, splicing, and post-transcriptional regulation. LncRNAs were aberrantly expressed in most hematological malignancies including lymphoma, participating in tumor suppression or promoting oncogenesis and modulating key genes in different pathways. The specific expression patterns of lncRNAs in lymphoma make them good candidates to be used as diagnostic biomarkers or as therapeutic targets. LncRNAs can be targeted by multiple approaches including nucleic acid therapeutics, CRISPR/Cas genome editing techniques, small molecule inhibitors, and gene therapy. Efforts are made to develop therapeutic strategies aimed at targeting lncRNAs, but there are still some avenues to be covered before they can be applied to the clinical treatment of lymphoma.

A graphene oxide-based hairpin probe coupling duplex-specific nuclease signal amplification for detection and imaging of mRNA in living cells

In situ imaging of mRNA in living cells can help to monitor the real time mRNA expression and also useful for diagnosis and prognosis of the diseases. In this study, a new strategy was designed for simple, sensitive, and selective platform to detect the mRNA levels by combining a hairpin probe-graphene oxide (HP1/GO) and duplex-specific nuclease signal amplification (DSNSA). Initially, the DNA probe was adsorbed on the surface of GO to protect it from enzymatic digestion. Then, the target mRNA (T1) was hybridized with a partial hairpin probe which formed a duplex. Finally, under the action of DSN nuclease, the ssDNA in the DNA/RNA hybrid was selectively cleaved and produced small fragments. Then, T1 triggered the next reaction cycle, constituting a new circular exponential amplification. Here, we conclude that this assay is highly sensitive for the detection of target mRNA with the lower detection limit of 1 fM under optimal conditions. Furthermore, this strategy was successfully used for imaging of mRNA in living cells.

Emerging roles of long non-coding RNAs in cancer

Cancer is a physiological condition that has both the endogenous and exogenous influences on its progression. It originates from unusual cell growth, where the cells undergo massive genetic alterations, bypass the signaling machinery and compromise its genetic cohesion. Literature has well narrated the DNA damage studies including driver mutations that interfere with the treatment strategies. However, with evolving medical excellence, recent day studies are trying to unveil the contribution of RNAs in the progression of tumor malignancies. A number of non-coding RNAs have been identified as an active component in cancer genomics. This article aims to review the role of long non-coding RNAs in the spectra of cancers and its prognostic value as the biomarkers in molecular targeting with clinical utility and therapeutic beneficence.

SNHG8 is identified as a key regulator in non-small-cell lung cancer progression sponging to miR-542-3p by targeting CCND1/CDK6

Background

Recently, various dynamically expressed lncRNAs are known to play critical roles in cancer progression. Small nucleolar RNA host genes (SNHG), a stable cytoplasmic lncRNA, which have been widely reported to act as an oncogene in non-small cell lung cancer (NSCLC). As an important member of SNHG, SNHG8 have been suggested to over-expressed in several cancer disease, while the biological function in NSCLC remains unclear.

Purpose

Here we investigated the biological function and underlying mechanism of SNHG8 in human NSCLC.

Patients and methods

The relationship between SNHG8 expression and clinicopathologic characteristic in NSCLC patients were observed from January 2014 to December 2014 in 120 NSCLC patients. The expression of SNHG8 were analyzed by qRT-PCR assay in cancer tissues and cells. Cell proliferation ability were detected in NSCLC cells by CCK-8 assay. Flow cytometric analysis were performed to detected the cell apoptosis and cell cycle. Luciferase assay and Western blot assay were performed on NSCLC cells to detected the underlying mechanism of SNHG8 in NSCLC. Moreover, Tumor xenografts in nude mice were performed to detected the in vivo function of SNHG8.

Results

SNHG8 was over-expressed in NSCLC tissues and cells. Patients with high SNHG8 expression have poorer overall survival (OS) and progression-free survival (PFS) than the patients with low SNHG8 expression. SNHG8 knockdown inhibited NSCLC cell proliferation in vitro and in vivo, arrested cell cycle in the G0/G1 phase via targeting miR-542-3p/CCND1/ CDK6, and induced cell apoptosis via activation of Caspase-3.

Conclusion

SNHG8 negatively regulated miR-542-3p in NSCLC progression by regulating downstream effectors including CCND1 and CDK6. SNHG8 showed great potential for the application in the treatment of NSCLC.

Long noncoding RNA Z38 promotes cell proliferation and metastasis and inhibits cell apoptosis in human gastric cancer

Gastric cancer is one of the leading causes of cancer-associated mortality and has a high tendency to metastasize, making it a priority to develop novel diagnostic and treatment methods at the early stages. The present study investigated the role of a newly-discovered long non-coding RNA, Z38, in gastric cancer cell proliferation, metastasis and apoptosis. It was observed that Z38 was upregulated in tissues from patients with gastric cancer as well as in cultured gastric cancer cells. Knockdown of Z38 decreased the cell proliferative rate, as evidenced by colony formation assays and cell proliferation assays. In addition, Transwell assays and wound-healing assays demonstrated that depletion of Z38 significantly inhibited cell migration and invasion in AGS and MKN74 cells. Furthermore, a cell apoptosis assay and measurement of relative activities of related caspases revealed that depletion of Z38 increased cell apoptosis by promoting the activities of caspase-3 and caspase-9, but not that of caspase-8. Finally, western blot analysis further demonstrated the role of Z38 in the apoptosis of AGS and MKN74 cells. These results suggested that Z38 promotes cell proliferation and metastasis, and inhibits cell apoptosis in gastric cancer. Z38 may represent a novel therapeutic target for the treatment of gastric cancer in clinic.

NEAT1 contributes to breast cancer progression through modulating miR-448 and ZEB1

Breast cancer is a kind of common female cancers. Increasing evidence has exhibited that lncRNAs exert a crucial role in breast cancer. So far, the mechanism of lncRNAs in breast cancer is still not well established. In our current study, we focused on the biological role of lncRNA Nuclear Enriched Abundant Transcript 1 (NEAT1) in breast cancer. We observed that NEAT1 levels were significantly increased in human breast cancer cells including MCF-7, MDA-MB-453, MDA-MB-231, and SKBR3 cells compared to normal mammary epithelial cells MCF-10A while miR-448 was decreased. We found that downregulation of NEAT1 was able to inhibit the growth of breast cancer cells and miR-448 mimic exerted the similar function. Bioinformatics analysis and dual luciferase reporter assays confirmed the negative correlation between NEAT1 and miR-448 in vitro. In addition, ZEB1 was predicted as a novel mRNA target of miR-448. Overexpression of NEAT1 can induce breast cancer cell growth, migration, and invasion by inhibiting miR-448 and upregulating ZEB1. It was demonstrated that NEAT1 can increase ZEB1 levels while miR-448 mimic can repress ZEB1. It was speculated in our study that NEAT1 can serve as a competing endogenous lncRNA (ceRNA) to modulate ZEB1 by sponging miR-448 in breast cancer. To conclude, we uncovered that NEAT1 participated in breast cancer progression by regulating miR-448 and ZEB1. NEAT1 can be provided as a vital biomarker in breast cancer diagnosis and treatment therapy.

MiRNA-545 negatively regulates the oncogenic activity of EMS1 in gastric cancer

Gastric cancer (GC) is a common malignant tumor of the digestive system. In addition, GC metastasis is an extremely complicated process. In this article, high expression levels of EMS1 mRNA and protein were found to be positively correlated with an enhanced malignant potential of GC cells and a poor clinical prognosis of GC patients. Interestingly, the expression levels of EMS1 mRNA and protein in GC cells were inhibited by microRNA-545 (miR-545), which was identified by a bioinformatics analysis. The expression level of miR-545 in carcinoma tissues was significantly lower than that in para-carcinoma tissues. The proliferation and epithelial-mesenchymal transition (EMT) of GC cells were suppressed by exogenous oligonucleotides of miR-545 mimics. In addition, the expression levels of EMT-associated markers were altered with the expression of miR-545. Notably, the growth rates of tumors in nude mice were seriously restrained by an intratumoral injection of oligonucleotides of the miR-545 mimics. These results suggest a negative regulatory role of miR-545 on the oncogenic activity of EMS1. In addition, EMS1 and miR-545 may be potential biomarkers for GC diagnosis. Synthesized oligonucleotides of miR-545 mimics may be developed as important gene medicines for GC therapy in the future.

Lnc-ing non-coding RNAs with metabolism and diabetes: roles of lncRNAs

Type 2 diabetes is a complex metabolic disorder characterized by insulin resistance and pancreatic β-cell dysfunction. Deregulated glucose and lipid metabolism are the primary underlying manifestations associated with this disease and its complications. Long non-coding RNAs (lncRNAs) are a novel class of functional RNAs that regulate a variety of biological processes by a diverse interplay of mechanisms including recruitment of epigenetic modifiers, transcriptional and post-transcriptional regulation, control of mRNA decay, and sequestration of transcription factors. Although the underlying causes that define the diabetic phenotype are extremely intricate, most of the studies in the last decades were mostly centered on protein-coding genes. However, current opinion in the recent past has authenticated the contributions of diverse lncRNAs as critical regulatory players during the manifestation of diabetes. The current review will highlight the importance of lncRNAs in regulating cellular processes that govern metabolic homeostasis in key metabolic tissues. A more in-depth understanding of lncRNAs may enable their exploitation as biomarkers or for therapeutic applications during diabetes and its associated complications.

Deciphering the roles of lncRNAs in breast development and disease

Breast cancer is the second leading cause of cancer related deaths in women. It is therefore important to understand the mechanisms underlying breast cancer development as well as raises the need for enhanced, non-invasive strategies for novel prognostic and diagnostic methods. The emergence of long non-coding RNAs (lncRNAs) as potential key players in neoplastic disease has received considerable attention over the past few years. This relatively new class of molecular regulators has been shown from ongoing research to act as critical players for key biological processes. Deregulated expression levels of lncRNAs have been observed in a number of cancers including breast cancer. Furthermore, lncRNAs have been linked to breast cancer initiation, progression, metastases and to limit sensitivity to certain targeted therapeutics. In this review we provide an update on the lncRNAs associated with breast cancer and mammary gland development and illustrate the versatility of such lncRNAs in gene control, differentiation and development both in normal physiological conditions and in diseased states. We also highlight the therapeutic and diagnostic potential of lncRNAs in cancer.

Knockdown of lncRNA HNF1A-AS1 inhibits oncogenic phenotypes in colorectal carcinoma

Long non-coding RNAs (lncRNAs) have been demonstrated to serve important roles in the development and progression of cancer. Recently HNF1A antisense RNA 1 (HNF1A‑AS1), a lncRNA, has been reported as exhibiting a potential oncogenic role in the development of many types of cancer. However, the expression and the role of HNF1A‑AS1 in colorectal carcinoma (CRC) remains unclear. In the present study, the role of HNF1A‑AS1 in CRC was examined for the first time and its correlation with CRC cell biological behaviors was analyzed. The results demonstrated that HNF1A‑AS1 was distinctly upregulated in CRC tissues and associated with CRC metastasis to the lymph nodes. Reverse transcription‑quantitative polymerase chain reaction revealed that HNF1A‑AS1 was also upregulated in CRC cell lines and localized in the nucleus. In addition, knockdown of HNF1A‑AS1 expression notably inhibited CRC cell proliferation, migration, invasion and colony formation, and suppressed S‑phase entry in vitro. Taken together, these results suggested that HNF1A‑AS1 might serve as a promising prognostic marker for CRC tumorigenesis and progression.

LncRNA as a Therapeutic Target for Angiogenesis

BACKGROUND

Out of 3 billion base pairs in human genome only ~2% code for proteins; and out of 180,000 transcripts in human cells, about 20,000 code for protein, remaining 160,000 are non-coding transcripts. Most of these transcripts are more than 200 base pairs and constitute a group of long non-coding RNA (lncRNA). Many of the lncRNA have its own promoter, and are well conserved in mammals. Accumulating evidence indicates that lncRNAs act as molecular switches in cellular differentiation, movement, apoptosis, and in the reprogramming of cell states by altering gene expression patterns. However, the role of this important group of molecules in angiogenesis is not well understood. Angiogenesis is a complex process and depends on precise regulation of gene expression.

CONCLUSION

Dysregulation of transcription during this process may lead to several diseases including various cancers. As angiogenesis is an important process in cancer pathogenesis and treatment, lncRNA may be playing an important role in angiogenesis. In support of this, lncRNA microvascular invasion in hepatocellular carcinoma (MVIH) has been shown to activate angiogenesis. Furthermore, lncRNA-Meg3-knockout mouse showed increased expression of vascular endothelial growth factor pathway genes and increased cortical microvessel density. Overall, there is strong evidence that lncRNA is an important class of regulatory molecule, and a number of studies have demonstrated that these can be targeted to change cellular physiology and functions. In this review, we have attempted to summarize these studies and elucidate the potential of this novel regulatory molecule as a therapeutic target.

A three-long noncoding RNA signature as a diagnostic biomarker for differentiating between triple-negative and non-triple-negative breast cancers

BACKGROUND

Triple-negative breast cancer (TNBC) is an aggressive cancer with unfavorable outcome and it is useful to explore noninvasive biomarkers for its early diagnosis. Here, we identified differentially expressed long noncoding RNAs (lncRNAs) in blood samples of patients with TNBC to assess their diagnostic value.

METHODS

Differential expression of lncRNAs in plasma of patients with TNBC (n = 25) and non-TNBC (NTNBC; n = 35) and in healthy controls was compared by microarray analysis and validated by real-time PCR. lncRNA expression between plasma and BC tissues was compared using Pearson correlation test. Logit model was used to obtain a new lncRNA-based score. Receiver operating characteristic analysis was performed to assess the diagnostic value of the selected lncRNAs.

RESULTS

Microarray data showed that 41 lncRNAs were aberrantly expressed. Among these, antisense noncoding RNA in the INK4 locus (ANRIL), hypoxia inducible factor 1alpha antisense RNA-2 (HIF1A-AS2), and urothelial carcinoma-associated 1 (UCA1) were markedly upregulated in plasma of patients with TNBC compared with patients with NTNBC (P < 0.01). HIF1A-AS2 expression was positively associated with its tissue levels (r = 0.670, P < 0.01). AUC (95% CI) of ANRIL, HIF1A-AS2, and UCA1 was 0.785 (0.660-0.881), 0.739 (0.610-0.844), and 0.817 (0.696-0.905), respectively. TNBCSigLnc-3, a new score obtained using the logit model, showed excellent diagnostic performance, with AUC of 0.934 (0.839-0.982), sensitivity of 76.0%, and specificity of 97.1%.

CONCLUSION

ANRIL, HIF1A-AS2, and UCA1 expression was significantly increased in plasma of patients with TNBC, suggesting their use as TNBC-specific diagnostic biomarkers.

Prognostic significance of long noncoding RNA Z38 as a candidate biomarker in breast cancer

BACKGROUND

Long noncoding RNA (lncRNA) Z38 has been shown to promote cell proliferation and tumorigenesis in breast cancer. However, expression pattern and prognostic value of lncRNA Z38 in breast cancer patients remain elusive.

METHODS

The expression levels of SPRY4-IT1 in 110 self-paired specimens of breast cancer and adjacent normal breast tissues were measured by quantitative real-time PCR (qRT-PCR), and its correlation with overall survival of patients with breast cancer was further statistically analyzed.

RESULTS

Compared with normal breast tissues, Z38 was upregulated in breast cancer tissues. Furthermore, of 110 breast cancer patients, high Z38 expression was significantly associated with tumor-node-metastasis stage and lymph node metastasis. Further analysis using the Cox regression model revealed that Z38 expression was an independent prognostic factor of overall survival in patients with breast cancer (hazard ratio=4.74, 95% confidence interval 2.41-9.32). The nomogram presents a good prediction of the probability of overall survival of breast cancer patients (c-index: 0.792), and its predictive efficiency was further confirmed by the calibration curve.

CONCLUSION

Our data highlighted the potential of lncRNA Z38 as novel candidate biomarker to identify patients with breast cancer at high risk of tumor death.

dNK derived IFN-γ mediates VSMC migration and apoptosis via the induction of LncRNA MEG3: A role in uterovascular transformation

INTRODUCTION

Appropriate spiral artery remodeling is critical for successful fetal development and pregnancy outcomes. The vascular smooth muscle cell (VSMC) loss and separation, involving cell apoptosis and migration, plays an important role in this process. Decidual natural killer cells (dNK)-derived interferon gamma (IFN-γ), a key regulator of uterine arterial remodeling, can facilitate separation of VSMC layers, however, the specific mechanisms of it action are unknown. Long non-coding RNA MEG3 functions as tumor suppressor by regulating apoptosis and migration. Moreover, IFN-γ has been shown to influence cell vitality through regulating MEG3 expression. However, the functional role of dNK derived IFN-γ and MEG3 on VSMC viability, as well as the relationship between IFN-γ and MEG3 in VSMCs, has not been completely elaborated.

METHODS

The up-regulation strategies and reagent treatment were employed to detect the effects of MEG3 and dNK/IFN-γ on VSMC proliferation, apoptosis and migration. At the same time, MEG3, p53 and matrix metalloproteinase 2 (MMP-2) expressions were investigated.

RESULTS

dNK/IFN-γ treatment led to up-regulation of MEG3 expression in VSMCs. Both MEG3 over-expression and dNK/IFN-γ treatment inhibited VSMC proliferation, stimulated VSMC migration and resulted in a small but significant induction of VSMC apoptosis, as well as promoted p53 and MMP-2 expression in VSMCs.

DISCUSSION

MEG3 is regulated by dNK-derived IFN-γ and regulates VSMC migration and apoptosis. Therefore, it may be an important positive regulator in VSMC loss from the maternal uterine spiral arteries during vascular transformation.

Current Status of Long Non-Coding RNAs in Human Breast Cancer

Breast cancer represents a major health burden in Europe and North America, as recently published data report breast cancer as the second leading cause of cancer related death in women worldwide. Breast cancer is regarded as a highly heterogeneous disease in terms of clinical course and biological behavior and can be divided into several molecular subtypes, with different prognosis and treatment responses. The discovery of numerous non-coding RNAs has dramatically changed our understanding of cell biology, especially the pathophysiology of cancer. Long non-coding RNAs (lncRNAs) are non-protein-coding transcripts >200 nucleotides in length. Several studies have demonstrated their role as key regulators of gene expression, cell biology and carcinogenesis. Deregulated expression levels of lncRNAs have been observed in various types of cancers including breast cancer. lncRNAs are involved in cancer initiation, progression, and metastases. In this review, we summarize the recent literature to highlight the current status of this class of long non-coding lncRNAs in breast cancer.

Long non-coding RNA CCAT2 functions as an oncogene in hepatocellular carcinoma, regulating cellular proliferation, migration and apoptosis

An increasing number of studies have demonstrated that the dysregulation of long non-coding RNAs (lncRNAs) may serve an important role in tumor progression. Previous studies have reported that the lncRNA, colon cancer associated transcript 2 (CCAT2), was highly expressed in various tumors. However, the function of CCAT2 in hepatocellular carcinoma (HCC) has not yet been elucidated. The aim of the present study was to identify novel oncogene lncRNAs and investigate their physiological function and mechanism in HCC. Using reverse transcription-quantitative polymerase chain reaction, it was observed that CCAT2 was upregulated in HCC tissues and human HCC cell lines. Furthermore, the impacts of CCAT2 on cell proliferation, migration and apoptosis were analyzed using cell migration, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and enzyme-linked immunosorbent assay analysis respectively. The overexpression of CCAT2 using a synthesized vector significantly promoted cell migration and proliferation, and inhibited apoptosis of HCC cells in vitro. The suppression of CCAT2 expression resulted in opposing effects. To the best of our knowledge, the present study is the first to demonstrate that CCAT2 functions as a oncogene in HCC. Further investigation is required to clarify the molecular mechanisms of this lncRNA in HCC development.