Long Non-Coding RNA SNHG6 as a Potential Biomarker for Hepatocellular Carcinoma

Silencing long non-coding RNA linc00689 suppresses the growth and invasion of osteosarcoma cells by targeting miR-129-5p/NUSAP1

Long non-coding RNAs (lncRNAs) have been reported to play a critical role in the progression and metastasis of osteosarcoma. Recently, long intergenic non-protein coding RNA 689 (linc00689) has been shown to be involved in glioma. However, the precise role of linc00689 in osteosarcoma is unknown. In this study, our data demonstrated that silencing linc00689 by siRNA markedly suppressed the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of MG63 and SAOS-2 cells. Bioinformatics analysis and dual-luciferase reporter assay revealed that linc00689 could bind to miR-129-5p. Moreover, NUSAP1 was a target of miR-129-5p and positively regulated by linc00689. Further, NUSAP1 overexpression enhanced MG63 cell behaviour and abolished the inhibitory effects of linc00689 knockdown on the proliferation, migration, invasion and EMT of MG63 cells. In conclusion, linc00689 exerts an oncogenic role in the progression of osteosarcoma, which works via the miR-129-5p/NUSAP1 axis.

Natural products and long noncoding RNA signatures in gallbladder cancer: a review focuses on pathogenesis, diagnosis, and drug resistance

Gallbladder cancer (GBC) is an aggressive and lethal malignancy with a poor prognosis. Long noncoding RNAs (lncRNAs) and natural products have emerged as key orchestrators of cancer pathogenesis through widespread dysregulation across GBC transcriptomes. Functional studies have revealed that lncRNAs interact with oncoproteins and tumor suppressors to control proliferation, invasion, metastasis, angiogenesis, stemness, and drug resistance. Curcumin, baicalein, oleanolic acid, shikonin, oxymatrine, arctigenin, liensinine, fangchinoline, and dioscin are a few examples of natural compounds that have demonstrated promising anticancer activities against GBC through the regulation of important signaling pathways. The lncRNAs, i.e., SNHG6, Linc00261, GALM, OIP5-AS1, FOXD2-AS1, MINCR, DGCR5, MEG3, GATA6-AS, TUG1, and DILC, are key players in regulating the aforementioned processes. For example, the lncRNAs FOXD2-AS1, DILC, and HOTAIR activate oncogenes such as DNMT1, Wnt/β-catenin, BMI1, and c-Myc, whereas MEG3 and GATA6-AS suppress the tumor proteins NF-κB, EZH2, and miR-421. Clinically, specific lncRNAs can serve as diagnostic or prognostic biomarkers based on overexpression correlating with advanced TNM stage, metastasis, chemoresistance, and poor survival. Therapeutically, targeting aberrant lncRNAs with siRNA or antisense oligos disrupts their oncogenic signaling and inhibits GBC progression. Overall, dysfunctional lncRNA regulatory circuits offer multiple avenues for precision medicine approaches to improve early GBC detection and overcome this deadly cancer. They have the potential to serve as novel biomarkers as they are detectable in bodily fluids and tissues. These findings enhance gallbladder treatments, mitigating resistance to chemo- and radiotherapy.

Impacts of host factors on susceptibility to SARS-CoV-2 infection and COVID-19 progression

SARS-CoV-2, identified in Wuhan, China, in December 2019, is the third coronavirus responsible for a global epidemic, following SARS-CoV (2002) and MERS-CoV (2012). Given the recent emergence of COVID-19, comprehensive immunological data are still limited. The susceptibility and severity of SARS-CoV-2 infection are influenced by various host factors, including hormonal changes, genetic variations, inflammatory biomarkers, and behavioral attitudes. Identifying genetic factors contributing to infection severity may accelerate therapeutic development, including drug repurposing, natural extracts, and post-vaccine interventions (Initiative and Covid, 2021). This review discusses the human protein machinery involved in (a) SARS-CoV-2 host receptors, (b) the human immune response, and (c) the impact of demographic and genetic differences on individual risk for COVID-19. This review aims to clarify host factors implicated in SARS-CoV-2 susceptibility and progression, highlighting potential therapeutic targets and supportive treatment strategies.

LncRNA Genes of the SNHG Family: Co-methylation and Common Functions in Ovarian Cancer

Genes of the small nucleolar RNA host gene (SNHG) family may participate in oncogenesis through the regulatory functions of encoded long non-coding RNAs (lncRNAs) and by influencing formation of small nucleolar RNAs and ribosome biogenesis. The aim of this work was to evaluate changes in the methylation levels and extent of co-methylation of the SNHG family lncRNA genes (SNHG1, GAS5/SNHG2, SNHG6, SNHG12, SNHG17) in clinical samples of ovarian cancer (OC) as an indication for the similarity of their roles in oncogenesis. Analysis of a representative set of 122 OC samples by quantitative methylation-specific PCR showed a statistically significant (p < 0.01-0.0001) increase in the methylation level of all five studied lncRNA genes. There was also a correlation between the increased methylation levels of GAS5, SNHG6, and SNHG12 and OC progression (clinical stage, tumor size, and metastasis), indicating possible functional significance of hypermethylation of these genes. For four genes (SNHG1, GAS5, SNHG6, and SNHG12), a statistically significant pairwise positive correlation of methylation levels (co-methylation) was observed (rs > 0.35; p ≤ 0.001), which was in agreement with the GEPIA 2.0 data (426 OC samples) showing co-expression of these genes (rs > 0.5; p < 0.001). The correlation between the expression levels of GAS5 and SNHG6 was confirmed by RT-qPCR (rs = 0.46; p = 0.007). Bioinformatics analysis predicted miRNAs common for the SNHG1, GAS5, SNHG6, and SNHG12 lncRNA and potentially capable of interacting with one or more of these lncRNAs via competing endogenous RNA mechanism, as well as mRNAs, whose expression might be affected by the studied lncRNAs. We also investigated a possible involvement of genes for these mRNAs in oncogenesis-related processes, such as RNA processing and splicing and epithelial-mesenchymal transition. As a result of this work, four SNHG family lncRNAs with coregulation and joint putative biological functions in the pathogenesis of OC were identified.

Functional role of lncRNAs in gastrointestinal malignancies: the peculiar case of small nucleolar RNA host gene family

Long noncoding RNAs (lncRNAs) play crucial roles in normal physiology and are often de-regulated in disease states such as cancer. Recently, a class of lncRNAs referred to as the small nucleolar RNA host gene (SNHG) family have emerged as important players in tumourigenesis. Here, we discuss new findings describing the role of SNHGs in gastrointestinal tumours and summarize the three main functions by which these lncRNAs promote carcinogenesis, namely: competing with endogenous RNAs, modulating protein function, and regulating epigenetic marking. Furthermore, we discuss how SNHGs participate in different hallmarks of cancer, and how this class of lncRNAs may serve as potential biomarkers in cancer diagnosis and therapy.

LncRNA SNHG6 role in clinicopathological parameters in cancers

RNA sequencing has revealed that a substantial portion of the human genome undergoes transcription, yet a minimal fraction of these transcripts translates into proteins. LncRNAs, RNA molecules less than 200 nt in length, once deemed as transcriptional noise, have now emerged as crucial regulators of numerous cellular processes. This review focuses on the lncRNA SNHG6, aiming to elucidate its biogenesis, the pivotal roles it plays, and its mechanisms in facilitating the hallmarks of cancer. A comprehensive literature review and analysis were undertaken to delve into the biogenesis of SNHG6, its roles in cellular processes, and the mechanisms through which it contributes to the hallmarks of cancer. SNHG6 is a notable lncRNA, observed to be overexpressed in various cancer types; its perturbation has been linked to tumor progression, emphasizing its significance in oncogenesis. This lncRNA contributes to a range of cellular aberrations, influencing transcriptional, post-transcriptional, and epigenetic processes of mRNA, ultimately driving cancerous transformations. LncRNA SNHG6 serves as a potential biomarker and therapeutic target due to its association with tumorigenesis. Understanding its mechanism and role in cancer can pave the way for novel diagnostic and therapeutic strategies.

Long noncoding RNA SNHG6 silencing sensitized esophageal cancer cells to 5-FU via EZH2/STAT pathway

Chemotherapy was the main treatment method for esophageal cancer (EC) patients. However, chemotherapy resistance due to multiple factors is a major barrier to EC treatment. For investigating how small nucleolar RNA host gene 6 (SNHG6) affected the 5-fluorouracil (5-FU) resistance in EC as well as its possible molecular mechanism. This work conducted cell viability assay, clone formation, scratch assays together with cell apoptosis for evaluating the roles of SNHG6 and enhancer of zeste homolog 2 (EZH2, the histone-lysine N-methyltransferase). Relevant molecular mechanism was identified by RT-qPCR analysis together with Western-blot (WB) assays. Our data showed that SNHG6 expression increased in EC cells. SNHG6 promotes colony formation and migration, whereas suppresses EC cell apoptosis. SNHG6 silencing markedly promoted 5-FU-mediated suppression on KYSE150 and KYSE450 cells. Additional mechanism studies showed that SNHG6 modulating STAT3 and H3K27me3 via promoting EZH2 level. Similar to the function of SNHG6, abnormal expression of EZH2 promotes the malignancy of EC and intensifies its resistance to 5-FU. In addition, overexpression of EZH2 abolished the role of SNHG6 silencing in 5-FU sensitivity in EC cells. SNHG6 overexpression promoted malignancy of EC and increased EC cell resistance to 5-FU. Besides, further molecular mechanism studies provided a novel regulatory pathways that SNHG6 knockdown promoted EC cell sensitivity to 5-FU by modulating STAT3 and H3K27me3 via promoting EZH2 expression.

Probabilistic embedding, clustering, and alignment for integrating spatial transcriptomics data with PRECAST

Spatially resolved transcriptomics involves a set of emerging technologies that enable the transcriptomic profiling of tissues with the physical location of expressions. Although a variety of methods have been developed for data integration, most of them are for single-cell RNA-seq datasets without consideration of spatial information. Thus, methods that can integrate spatial transcriptomics data from multiple tissue slides, possibly from multiple individuals, are needed. Here, we present PRECAST, a data integration method for multiple spatial transcriptomics datasets with complex batch effects and/or biological effects between slides. PRECAST unifies spatial factor analysis simultaneously with spatial clustering and embedding alignment, while requiring only partially shared cell/domain clusters across datasets. Using both simulated and four real datasets, we show improved cell/domain detection with outstanding visualization, and the estimated aligned embeddings and cell/domain labels facilitate many downstream analyses. We demonstrate that PRECAST is computationally scalable and applicable to spatial transcriptomics datasets from different platforms.

Inferring miRNA sponge modules across major neuropsychiatric disorders

The role of non-coding RNAs in neuropsychiatric disorders (NPDs) is an emerging field of study. The long non-coding RNAs (lncRNAs) are shown to sponge the microRNAs (miRNAs) from interacting with their target mRNAs. Investigating the sponge activity of lncRNAs in NPDs will provide further insights into biological mechanisms and help identify disease biomarkers. In this study, a large-scale inference of the lncRNA-related miRNA sponge network of pan-neuropsychiatric disorders, including autism spectrum disorder (ASD), schizophrenia (SCZ), and bipolar disorder (BD), was carried out using brain transcriptomic (RNA-Seq) data. The candidate miRNA sponge modules were identified based on the co-expression pattern of non-coding RNAs, sharing of miRNA binding sites, and sensitivity canonical correlation. miRNA sponge modules are associated with chemical synaptic transmission, nervous system development, metabolism, immune system response, ribosomes, and pathways in cancer. The identified modules showed similar and distinct gene expression patterns depending on the neuropsychiatric condition. The preservation of miRNA sponge modules was shown in the independent brain and blood-transcriptomic datasets of NPDs. We also identified miRNA sponging lncRNAs that may be potential diagnostic biomarkers for NPDs. Our study provides a comprehensive resource on miRNA sponging in NPDs.

The targeted inhibition of prostate cancer by iron-based nanoparticles based on bioinformatics

Prostate cancer is an epithelial malignant tumor of the prostate, and it is one of the malignant tumors with a high incidence of urogenital system in men. The local treatment of prostate cancer is mainly radical resection and radical radiotherapy, but they are not applicable to advanced prostate cancer. Systemic therapy mainly includes targeted therapy and immunotherapy which could cause many complications, and will affect the prognosis and quality of life of patients. It is urgent to find new treatments for prostate cancer. Bioinformatics offers hope for us to find reliable therapeutic targets. Bioinformatics can use the tumor informations in database and analyze them to screen out the best differentially expressed genes. Using the selected differentially expressed genes as targets, a gene interference plasmid was designed, and the constructed plasmid was used for targeted gene therapy. There are some problems about gene therapy that need to be solved, such as how to transfer genes to target cells is also an important challenge. Due to their large molecular weight and hydrophilic nature, they cannot enter cells through passive diffusion mechanisms. Here we synthesized a DNA carrier used surface modified iron based nanoparticles, and used it to load plasmid including ShRNA which can inhibit the expression of oncogene SLC4A4 selected by bioinformatics' method. After that we use this iron based nanoparticles/plasmid DNA nanocomposite to treat prostate cancer cells in vitro and in vivo. The target gene SLC4A4 we had selected using bioinformatics had a strong effect on the proliferation of prostate cells; Our nanocomposite could inhibit the expression of SLC4A4 effectively, it had strong inhibitory effects on prostate cancer cells both in vivo and in vitro, and can be used as a potential method for prostate cancer treatment.

LncRNA SNHG6 promotes G1/S-phase transition in hepatocellular carcinoma by impairing miR-204-5p-mediated inhibition of E2F1

Emerging evidence suggests that long noncoding RNAs (lncRNAs) function as competitive endogenous RNA (ceRNA) targeting proteins and genes; however, the role of lncRNAs in hepatocellular carcinoma (HCC) is not well understood. We investigated the mechanism by which lncRNA SNHG6 promotes the development of HCC. RT-qPCR revealed upregulated lncRNA SNHG6 in the HCC setting. Elevated SNHG6 expression was indicative of poor prognosis in patients with HCC. SNHG6 overexpression resulted in increased cyclin D1, cyclin E1, and E2F1 expression both in vitro and in vivo. SNHG6 also promoted HCC cell proliferation by enhancing G1-S phase transition in vitro. Dual luciferase reporter assays, RIP, and RNA pull-down assays demonstrated SNHG6 competitively bound to miR-204-5p and inhibited its expression preventing miR-204-5p from targeting E2F1. Overexpression of miR-204-5p abolished the effect of SNHG6. Our data suggest that SNHG6 functions as a ceRNA that targets miR-204-5p resulting in an increased E2F1 expression and enhanced G1-S phase transition, thereby promoting the tumorigenesis of HCC.

Circulating lncRNA DANCR as a potential auxillary biomarker for the diagnosis and prognostic prediction of colorectal cancer

Studies have shown that long non-coding RNAs (lncRNAs) play vital roles in the development of cancer, including colorectal cancer (CRC). Our purpose is to validate the diagnostic value of serum differentiation antagonizing non-protein coding RNA (DANCR) in CRC by focusing on its expression and clinical application. lncRNA expression profiles of CRC patients were obtained and analyzed by repurposing the publically available microarray data. Tissue or serum specimens were obtained from 40 patients with primary CRC, 10 patients with recurrent CRC, 40 patients with colorectal polyps, and 40 healthy controls. It was found that DANCR level in the CRC tissue and serum was significantly increased, and serum DANCR expression was decreased in post-operative patients as compared with that in pre-treatment patients and recurrent patients. In addition, serum DANCR expression was significantly correlated with different TNM stages. Correlation analysis of DANCR and other diagnostic indicators showed that the serum DANCR expression level was significantly correlated with CA199 but not with CEA in CRC patients. As for diagnostic efficiency by ROC analysis, the area under the curve (AUC) of serum DANCR was higher than that of CEA and CA199 in CRC group vs. colorectal polyp group. Simultaneous detection of DANCR, CEA and CA199 yielded the highest sensitivity and AUC as compared with either of them alone. Taken together, serum DANCR was up-regulated in CRC patients and high expression of DANCR may prove to be a potential biomarker for the diagnosis of CRC.

The Role of Epigenetics in Congenital Heart Disease

Congenital heart disease (CHD) is the most common birth defect among newborns worldwide and contributes to significant infant morbidity and mortality. Owing to major advances in medical and surgical management, as well as improved prenatal diagnosis, the outcomes for these children with CHD have improved tremendously so much so that there are now more adults living with CHD than children. Advances in genomic technologies have discovered the genetic causes of a significant fraction of CHD, while at the same time pointing to remarkable complexity in CHD genetics. For this reason, the complex process of cardiogenesis, which is governed by multiple interlinked and dose-dependent pathways, is a well investigated process. In addition to the sequence of the genome, the contribution of epigenetics to cardiogenesis is increasingly recognized. Significant progress has been made dissecting the epigenome of the heart and identified associations with cardiovascular diseases. The role of epigenetic regulation in cardiac development/cardiogenesis, using tissue and animal models, has been well reviewed. Here, we curate the current literature based on studies in humans, which have revealed associated and/or causative epigenetic factors implicated in CHD. We sought to summarize the current knowledge on the functional role of epigenetics in cardiogenesis as well as in distinct CHDs, with an aim to provide scientists and clinicians an overview of the abnormal cardiogenic pathways affected by epigenetic mechanisms, for a better understanding of their impact on the developing fetal heart, particularly for readers interested in CHD research.

LncRNA-SNHG6 promotes the progression of hepatocellular carcinoma by targeting miR-6509-5p and HIF1A

Background

Accumulating evidences have been reported that long noncoding RNAs play crucial roles in the progression of hepatocellular carcinoma (HCC). SnoRNA host gene 6 (SNHG6) is believed to be involved in several human cancers, but the specific molecular mechanism of SNHG6 in HCC is not well studied.

Methods

In this study, we experimentally down-regulated the SNHG6 in two hepatocellular carcinoma cell lines in vitro, and then measured the proliferation, migration and invasion abilities and the apoptotic levels. Also, we performed the xenograft assay to investigate the function of SNHG6 during the tumor growth in vivo.

Results

We found SNHG6 was highly expressed in HCC tissues. Next, using Hep3B and Huh7 cells, we confirmed knockdown of SNHG6 reduced the proliferation, migration and invasion abilities in vitro. Also, by bioinformatics analysis, further molecular and cellular experiments, we found miR-6509-5p bound to SNHG6 directly, and the expression level of HIF1A was regulated through SNHG6/miR-6509-5p axis. Finally, we found that down-regulation of SNHG6 dramatically reduced the tumor growth ability of Huh7 cells in vivo.

Conclusions

We concluded that SNHG6/miR-6509-5p/HIF1A axis functioned in the progression of hepatocellular carcinoma, and could be the promising therapeutic targets during the development of hepatocellular carcinoma drugs.

SP1-induced long non-coding RNA SNHG6 facilitates the carcinogenesis of chondrosarcoma through inhibiting KLF6 by recruiting EZH2

Small nucleolar RNA host gene 6 (SNHG6) is a newly discovered long non-coding RNA (lncRNA), while the regulatory mechanism of SNHG6 in chondrosarcoma is largely unknown. Here we found that SNHG6 expression was upregulated and showed positive correlation with the progression of chondrosarcoma. Functional assays demonstrated that SNHG6 was required for the proliferation, migration, and invasion of chondrosarcoma cells. Mechanistic study revealed that SNHG6 could recruit EZH2 and maintain high level of H3K27me3 to repress the transcription of tumor-suppressor genes, including KLF6. KLF6 was found to bind to the promoter region of SP1 and restrained its transcription, while SP1 could be recruited to the promoter region of SNHG6 and promoted its transcription to form a positive loop. In summary, this study reveals that SP1-induced SNHG6 forms a positive loop to facilitate the carcinogenesis of chondrosarcoma through the suppression of KLF6 by recruiting EZH2, which manifests the oncogenic function of SNHG6 in chondrosarcoma.

Knockdown of LINC00504 Inhibits the Proliferation and Invasion of Breast Cancer via the Downregulation of miR-140-5p

INTRODUCTION

Breast cancer is one of the most common cancers in the world. Long noncoding RNA 00504 (LINC00504) was reported to be a functional gene in some tumours but not breast. Accordingly, the purpose of this article is to study the function of LINC00504 in breast cancer.

METHODS

qPCR assay was used to detect the expression of LINC00504 in tissue and cell lines. The online database and chromatin immunoprecipitation assay (ChIP) were employed to confirm the transcription factor of LINC00504. Cell function assays including cell proliferation, migration and invasion were designed to detect the function of LINC00504 in vitro and in vivo. Luciferase reporter assay and RNA immunoprecipitation (RIP) assay were used to confirm the relationship between LINC00504 and miR-140-5p. And Western blot assay was employed for testing the key protein.

RESULTS

We found that LINC00504 is upregulated in breast cancer. In addition, we found that the transcription factor regulatory factor X5 (RFX5) can strongly bind to the LINC00504 promoter region and subsequently increase its transcriptional activity. We also found that the manipulation of RFX5 expression can significantly affect LINC00504 expression, which suggested that RFX5 can transcriptionally activate LINC00504 in breast cancer (BC). Knockdown of LINC00504 inhibits cell proliferation, migration and invasion in vitro and in vivo. We further found that LINCOO504 inhibits miR-140-5p, which decreases the levels of VEGFA. The further results showed that miR-140-5p was one of the target gene of LINC00504. The WB assay demonstrated that the E-cadherin was increased and Vimentin was decreased when knocking down of LINC00504 and they can be rescued while adding the inhibitors of miR-140-5p.

DISCUSSION

Our results demonstrated the mechanism by which the LINC00504-miR-140-5p-VEGFA axis participates in breast cancer cell proliferation and invasion and may lead to new lncRNA-based diagnostic or therapeutic strategies for breast cancer.

Long non-coding RNA SNHG9 inhibits ovarian cancer progression by sponging microRNA-214-5p

Ovarian cancer ranks 7th among the most common cancer types affecting women worldwide. A number of studies have confirmed that multiple long non-coding RNAs participate in the occurrence and progression of ovarian cancer. Small nucleolar RNA host gene 9 (SNHG9) serves a role in the progression of glioblastoma and pancreatic cancer. However, the specific biological function of SNHG9 in ovarian cancer has not yet been fully investigated. The present study aimed to determine the biological role and potential molecular mechanism underlying the influence of SNHG9 in ovarian cancer. SNHG9 expression in ovarian cancer cell lines and tissues were measured via reverse transcription-quantitative PCR analysis, and cell proliferation was detected via Cell Counting Kit-8 and colony formation assays. Flow cytometry was performed to assess cell cycle progression, and Transwell and wound healing assays were performed to assess cell invasion and migration abilities. Bioinformatics software was utilized to determine the target genes of SNHG9, which were subsequently verified via dual-luciferase reporter and RNA immunoprecipitation assays. The results demonstrated that SNHG9 expression was remarkably lower in ovarian cancer cell lines and tissues compared with the negative controls. Cell function assays demonstrated that decreased SNHG9 expression notably induced the migration, colony formation, proliferation and invasiveness of ovarian cancer cells. Furthermore, the inhibitory effect of SNHG9 on the migration, colony formation, proliferation and invasion of ovarian cancer cells was partially reversed by miR-214-5p upregulation. Thus, taken together, the current results suggest that SNHG9 may serve as a tumor suppressor gene in ovarian cancer by regulating the miR-214-5p/cryptochrome circadian regulator 2 axis.

Long non-coding RNA SNHG6 increases JAK2 expression by targeting the miR-181 family to promote colorectal cancer cell proliferation

BACKGROUND

Long non-coding RNA (lncRNA) small nucleolar RNA host gene 6 (SNHG6) exerts a regulatory role in cancer biology, although its detailed functions and mechanisms in colorectal cancer (CRC) still remain unclear.

METHODS

A quantitative reverse transcriptase-polymerase chain reaction was implemented to investigate the expression of SNHG6, miR-181 family and Janus kinase 2 (JAK2) in CRC tissues and cell lines. The proliferation of CRC cells was detected by a cell counting kit-8 assay, and the apoptosis of CRC cells was determined by flow cytometry analysis. The interaction of the miR-181 family with SNHG6 or with the 3'-untranslated region of JAK2 was validated by the luciferase reporter gene method. The effects of SNHG6 and the miR-181 family on JAK2 expression were analyzed by western blotting.

RESULTS

SNHG6 was significantly up-regulated in CRC samples. The knockdown of SNHG6 reduced the proliferation of CRC cells and promoted the apoptosis, whereas the over-expression of SNHG6 had the opposite effect. SNHG6 could bind with all the four members of the miR-181 family, and expression in miR-181 family members was significantly down-regulated in CRC samples. SNHG6 expression was negatively correlated with the miR-181 family member expression in CRC samples. Moreover, over-expressed SNHG6 significantly counteracted the inhibitory effect of miR-181 mimics on CRC cell proliferation, as well as the promoting effect on apoptosis. Furthermore, SNHG6 over-expression and knockdown can promote and inhibit JAK2 expression, respectively, and miR-181 family member function is opposite to that of SNHG6 by repressing JAK2.

CONCLUSIONS

SNHG6 can exert a cancer-promoting effect in CRC by targeting miR-181 family members and up-regulating JAK2.

Increased Expression Level of Long Noncoding RNA H19 in Plasma of Patients with Myocardial Infarction

Long noncoding RNAs (lncRNAs) are lengthy noncoding transcripts which are actively involved in crucial cellular pathways. Tissue-specific expression of lncRNAs besides its secretion into the body fluids, has made lncRNAs in attention as biomarkers of the diseases. According to the role of lncRNAs, especially H19 in cardiac regeneration, it is not surprising if their altered expression levels lead to cardiac diseases. In the present study, the relative expression of H19 was compared in the plasma of atherosclerotic myocardial infarction and control individuals by real time-PCR, and data were normalized using GAPDH. The association of plasma level of lipid and homocystine with H19 expression was also considered. The potential of H19 to discriminate the case from control was studied using the ROC analysis. We found that the plasma level of H19 transcript significantly increased in the plasma of patients in comparison with the control group. Additionally, the relative expression level of H19 was directly associated with the plasma homocystine level. The relative expression of H19 at threshold of 0.3 showed 70% sensitivity and 94% specificity to discriminate cases from controls. This study revealed that the expression level of H19 may be considered as a biomarker of myocardial infarction, although further studies are needed to generalize this finding.

LncRNA SNHG6 Induces Epithelial-Mesenchymal Transition of Pituitary Adenoma Via Suppressing MiR-944

Background:

Pituitary adenoma (PA) is a common primary brain tumor with invasive properties. Despite that long noncoding RNA (lncRNA) small nucleolar RNA host gene 6 (SNHG6) exerts oncogenic function in cancer cells and that miR-944 inhibits epithelial–mesenchymal transition (EMT) of cancer cells are well documented, few studies have explored the function and mechanism of SNHG6 and miR-944 in invasive pituitary adenoma (IPA).

Materials and Methods:

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expressions of SNHG6 and miR-944 in PA samples. Human PA cell line HP75 was used as a cell model. The biological effects of SNHG6 and miR-944 on HP75 cells were investigated with cell counting kit-8 (CCK-8) assay, Transwell assay, and scratch healing assay in vitro, respectively. Markers of EMT, including E-cadherin and vimentin, were detected by Western blot. Interactions between SNHG6 and miR-944, miR-944 and RAB11A were determined by bioinformatics analysis, qRT-PCR, and dual luciferase reporter assay.

Results:

SNHG6 was significantly upregulated in IPA samples, whereas miR-944 was downregulated. SNHG6 markedly promoted viability, migration, invasion, and EMT of PA cells, whereas miR-944 transfection had the opposite effects. SNHG6 could downregulate miR-944, and there was a negative correlation between SNHG6 expression and miR-944 expression in IPA samples. Besides, it was confirmed that miR-944 could pair with the 3′-untranslated region of RAB11A and repress its expression.

Conclusions:

This study authenticates that the SNHG6/miR-994/RAB11A axis plays a crucial role in regulating proliferation, migration, invasion, and EMT of IPA cells. SNHG6 and miR-994 can serve as novel valuable therapeutic targets for IPA.

Association of long-chain non-coding RNA GAS5 gene polymorphisms with prostate cancer risk and prognosis in Chinese Han population

BACKGROUND

To investigate the correlation between growth arrest-specific transcript 5 (GAS5) gene polymorphism and the risk and prognosis of prostate cancer in Chinese Han population.

METHODS

Sanger sequencing was used to analyze genotypes at the rs17359906 and rs1951625 loci of the GAS5 gene in 218 prostate cancer patients and 220 healthy controls. The follow-up period was from August 2016 to August 2019, and the relationships between GAS5 gene polymorphisms at the rs17359906 and rs1951625 loci and the recurrence-free survival rate of prostate cancer patients were analyzed.

RESULTS

GAS5 A-allele carriers at the rs17359906 locus were 3.44 times more likely to develop prostate cancer than G-allele carriers (95% confidence interval (CI): 2.38-4.96, P < .001). Carriers of the GAS5 A allele at the rs1951625 locus had a 1.40-fold higher risk of prostate cancer than carriers of the G allele (95% CI: 1.05-1.86, P = .027). Plasma prostate-specific antigen (PSA), body mass index (BMI), and rs17359906 and rs1951625 loci were independent risk factors for prostate cancer. GAS5 AA genotype and A-allele carriers (GA + AA) at the rs1951625 locus were significantly correlated with Gleason scores ≤7 (P < .05). GAS5 genes rs17359906 G > A and rs1951625 G > A were associated with high plasma PSA levels. The recurrence-free survival rate of patients with prostate cancer with AA genotype at the rs17359906 locus of GAS5 (66.67%) was significantly lower than that of the GA genotype (76.47%), whereas the GG genotype was the highest (91.96%), and the difference was statistically significant (P = .002). The recurrence-free survival rate of patients with prostate cancer with the AA genotype at the rs1951625 locus of GAS5 (75.00%) was significantly lower than that of the GA genotype (81.82%), whereas the GG genotype was the highest (87.76%) with a statistically significant difference (P = .025).

CONCLUSION

GAS5 rs17359906 G > A and rs1951625 G > A are significantly associated with an increased risk of prostate cancer and a reduction in three-year relapse-free survival.

MicroRNAs in Rectal Cancer: Functional Significance and Promising Therapeutic Value

It is well-known that microRNAs (miRNAs) are critical mediators of initiation and disease progression in many human cancers. Rectal cancer is a highly prevalent tumor, accounting for around one third of newly diagnosed colorectal cancers. The usefulness of miRNAs as clinical biomarkers predictive of the outcome and response to chemoradiotherapy has been well-reported for rectal cancer. However, the existing literature on their functional and therapeutic impact needs to be put in context to clarify their role in disease pathogenesis. Therfore, this review is focused on the functional relevance of miRNAs as key regulators of signaling pathways in rectal cancer and their potential therapeutic value as novel molecular targets in this disease.

Serum small extracellular vesicle-derived LINC00853 as a novel diagnostic marker for early hepatocellular carcinoma

This study aimed to identify novel long noncoding RNA (lncRNA) biomarkers for hepatocellular carcinoma (HCC) using publicly available tissue genomic datasets and validate their diagnostic utility for early-stage HCC. Differentially expressed lncRNAs between 371 HCC and 50 nontumor tissues were obtained from The Cancer Genome Atlas liver hepatocellular carcinoma (TCGA_LIHC) project. Subsequently, the expression of the serum- and extracellular vesicle (EV)-derived lncRNA was assessed in 10 patients with HCC and 10 healthy controls using RT-qPCR. The candidate lncRNAs were validated in 90 HCC and 92 non-HCC (29 healthy control, 28 chronic hepatitis, 35 liver cirrhosis) patients. The sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated for the candidate lncRNAs and the current HCC biomarker, alpha-fetoprotein (AFP). SFTA1P, HOTTIP, HAGLROS, LINC01419, HAGLR, CRNDE, and LINC00853 were markedly upregulated in HCC in TCGA_LIHC dataset. Among them, LINC00853 has not been reported in relation to HCC before. In patients with HCC, only expression of small EV-derived LINC00853 (EV-LINC00853) was increased. EV-LINC00853 showed excellent discriminatory ability in the diagnosis of all-stage HCC (AUC = 0.934, 95% confidence interval = 0.887-0.966). Moreover, using a 14-fold increase and 20 ng·mL^-1 as cutoffs for EV-LINC00853 expression and AFP level, respectively, EV-LINC00853 was found to have a sensitivity of 93.75% and specificity of 89.77%, while AFP showed only 9.38% sensitivity and 72.73% specificity for the diagnosis of early-stage HCC (mUICC stage I). EV-LINC00853 had a positivity of 97% and 67% in AFP-negative and AFP-positive early HCC, respectively. Serum EV-derived LINC00853 may be a novel potential diagnostic biomarker for early HCC, especially for AFP-negative HCC.

SPI1-induced upregulation of lncRNA SNHG6 promotes non-small cell lung cancer via miR-485-3p/VPS45 axis

More and more researches have proved that long noncoding RNAs (lncRNAs) are vital regulators and biological participants in human cancers [1-5]. SnoRNA host gene 6 (SNHG6) was found to have an effect on the early stage and tumorigenesis in many cancers [6-10]. However, the expression of SNHG6 and its role of in non-small cell lung cancer (NSCLC) still need to be investigated. This work aims to investigate the expression and its biological role in NSCLC. In our study, the expression of SNHG6 was abnormally high in NSCLC tissues and cells. The negative impact of SNHG6 expression on the overall survival of patients with NSCLC was analyzed with Kaplan Meier method. Functionally, loss of SNHG6 expression led to the inhibition on the growth, migration and invasion of NSCLC cells. Mechanistically, miR-485-3p was necessary for the regulatory relation between SNHG6 and VPS45. More importantly, SPI1 could promote the expression of SNHG6 via transcriptionally activation. In conclusion, we proved that SPI1/SNHG6/miR-485-3p/VPS45 axis exerted oncogenic role in the cellular process of NSCLC cells.

Prognostic and clinicopathological significance of SNHG6 in human cancers: a meta-analysis

Background

Recently, accumulating evidence has suggested that the aberrant expression of SNHG6 exists in a variety of tumors and has a correlation with poor clinical outcomes across cancer patients. Considering the inconsistent data among published studies, we aim to assess the prognostic effect of SNHG6 on malignancies.

Methods

We retrieved relevant publications in Web of Science, Embase, MEDLINE, PubMed and Cochrane Library based on predefined selection criteria, up to October 1, 2019. Pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were utilized to evaluate the correlation between SNHG6 and overall survival (OS), recurrence-free survival (RFS) and progression-free survival (PFS) as well as clinicopathology.

Results

In total, 999 patients from 14 articles were enrolled in our meta-analysis. The results revealed that augmented SNHG6 expression was significantly correlated with poor OS (HR = 2.20, 95% CI = 1.76–2.75, P < 0.001) and RFS (HR = 3.10, 95% CI = 1.90–5.07, P < 0.001), but not with PFS (HR = 2.11, 95% CI = 0.82–5.39, P = 0.120). In addition to lung cancer and ovarian cancer, subgroup analysis showed that the prognostic value of SNHG6 across multiple tumors was constant as the tumor type, sample size, and methods of data extraction changed. Moreover, cancer patients with enhanced SNHG6 expression were prone to advanced TNM stage (OR = 3.31, 95% CI = 2.46–4.45, P < 0.001), distant metastasis (OR = 4.67, 95% CI = 2.98–7.31, P < 0.001), lymph node metastasis (OR = 2.59, 95% CI = 1.41–4.77, P = 0.002) and deep tumor invasion (OR = 3.75, 95% CI = 2.10–6.69, P < 0.001), but not associated with gender, histological grade and tumor size.

Conclusions

SNHG6 may serve as a promising indicator in the prediction of prognosis and clinicopathological features in patients with different kinds of tumors.

Long noncoding RNA linc00467 plays an oncogenic role in hepatocellular carcinoma by regulating the miR-18a-5p/NEDD9 axis

Increasing evidence has shown that numerous long noncoding RNAs (lncRNAs) play critical roles in tumorigenesis. Herein, we investigated the biological role of lncRNA linc00467 in the cancer biology of hepatocellular carcinoma (HCC). We observed that linc00467 was upregulated in HCC tissues and cells. Silencing of linc00467 using small interfering RNA interference significantly inhibited the growth and motility of HCC cells, and increased cell apoptosis through regulating the Bcl-2/Bax axis and the caspase cascade, suggesting that linc00467 exerted oncogenic functions in the progression of HCC. Moreover, we found that linc00467 could target miR-18a-5p, and NEDD9 was a target for miR-18a-5p in HCC cells. Furthermore, either the miR-18a-5p inhibitor or upregulation of NEDD9 could recover the inhibitory effects caused by silencing of linc00467. In conclusion, our data highlighted the oncogenic role of linc00467 in HCC progression by regulating the miR-18a-5p/NEDD9 axis.

SNHG 6 promotes the progression of Colon and Rectal adenocarcinoma via miR-101-3p and Wnt/β-catenin signaling pathway

Background

Small nucleolar RNA host gene 6 (SNHG6) regulates diverse biological processes in cancers. Potential function of SNHG6 in human colon and rectal adenocarcinoma (CRC) was evaluated.

Methods

Quantitative real-time polymerase chain reaction, MTT assays, Colony formation assays, Transwell assay, Western Blotting and Luciferase reporter assays were performed to measure the biological functions and potential molecular mechanisms of SNHG6 in CRC.

Results

SNHG6 was over-expressed in CRC, and high expression of s SNHG6 were associated with short survival times. We then identified miR-101-3p as an inhibitory target of SNHG6. Knockdown of SNHG6 significantly decreased miR-101-3p expression. Moreover, silenced SNHG6 obviously inhibited CRC cell growth, weakened cell invasion capacity and blocked the Wnt/β-catenin signaling pathway.

Conclusion

SNHG6 could regulate the progression of CRC via modulating the expression levels of miR-101-3p and the activity of Wnt/β-catenin signaling.

LncRNA SNHG6 inhibits cell proliferation and metastasis by targeting ETS1 via the PI3K/AKT/mTOR pathway in colorectal cancer

The term ‘long non-coding RNAs’ (lncRNAs) refers to all non-protein coding transcripts >200 nucleotides in length. Dysregulation of lncRNAs has been identified in colorectal cancer, which is one of the more serious types of cancer worldwide, third place in the mortality rates, and is associated with poor prognoses. Novel evidence suggests that lncRNAs serve an important role in regulating the development and progression of colorectal cancer. In the present study, it was demonstrated that SNHG6 expression was downregulated in colorectal cancer tissues by reverse transcription quantitative polymerase chain reaction assays; however, ETS1 expression levels were upregulated. Overexpression of SNHG6 not only inhibited the proliferation of colon cancer cells in vitro by inducing apoptosis, but also inhibited cell proliferation, invasion and migration. The overexpression of SNHG6 inhibited colon cell viability and proliferation by targeting ETS1 through the phosphoinositide 3-kinase/protein kinase B/mechanistic target of rapamycin signaling pathway. These results suggested that SNHG6 may directly suppress ETS1, which may be one of potential mechanisms through which it inhibits the viability and proliferation of colorectal cancer cells, and it provides novel insight into the carcinogenesis of colorectal cancer. In addition, it may assist in the development of a treatment approach for ETS1-activated colorectal cancer.

Up-regulation of SNHG6 activates SERPINH1 expression by competitive binding to miR-139-5p to promote hepatocellular carcinoma progression

We aimed to assess the roles of small nucleolar RNA host gene 6 (SNHG6) in hepatocellular carcinoma (HCC) progression, and establish the lncRNA-miRNA-mRNA regulation mechanism for HCC therapy. SNHG6 is one of the host genes in small nucleolar RNAs (snoRNAs), which make a difference in the development of human cancers. SERPINH1 is a gene encoding a member of the serpin superfamily of serine proteinase inhibitors with miRNA predicted by TargetScan and DIANA Tools. SNHG6, serpin family H member 1 (SERPINH1) and miR-139-5p expression levels in HCC tissues and cells were determined by quantitative real-time PCR (qRT-PCR). Migration and invasion of HCC cells were measured by transwell assay. Cell cycle analysis was determined by using flow cytometry. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and colony formation assay were performed for cell viability analysis. The expression of SERPINH1 was detected by qRT-PCR and western blot. Dual-luciferase reporter gene assay was conducted to identify the targeted relationship between miR-139-5p and SNHG6, as well as SERPINH1 and miR-139-5p. The positive regulation between SNHG6 and SERPINH1 was demonstrated in this study. In contrast, miR-139-5p was significantly down-regulated in HCC cells, the inhibition of miR-139-5p promotes the proliferation of HCC cells, and accelerated the cell cycle of HCC cells. Our study demonstrated the co-expression of SNHG6 and SERPINH1 in HCC cells for the first time, which revealed that SNHG6 could serve as a novel oncogene for the HCC therapy by its regulation.

Analyses of a Panel of Transcripts Identified From a Small Sample Size and Construction of RNA Networks in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. Dysregulation of mRNAs and non-coding RNAs (ncRNAs) plays critical roles in the progression of HCC. Here, we investigated HCC samples by RNA-seq and identified a series of dysregulated RNAs in HCC. Various bioinformatics analyses established long non-coding RNA (lncRNA)-mRNA co-expression and competing endogenous RNA (ceRNA) networks in circRNA-miRNA-mRNA axis, indicating the potential cis and/or trans regulatory roles of lncRNAs and circRNAs. Moreover, GO pathway analysis showed that these identified RNAs were associated with many biological processes that were related to tumorigenesis and tumor progression. In conclusion, we systematically established functional networks of lncRNA-mRNA, circRNA-miRNA-mRNA to further unveil the potential interactions and biological processes in HCC. These results provide further insights into gene expression network of HCC and may assist future diagnosis of HCC.

Long noncoding RNAs biomarker-based cancer assessment

Cancer diagnosis have mainly relied on the incorporation of molecular biomarkers as part of routine diagnostic tool. The molecular alteration ranges from those involving DNA, RNA, noncoding RNAs (microRNAs and long noncoding RNAs [lncRNAs]) and proteins. lncRNAs are recently discovered noncoding endogenous RNAs that critically regulates the development, invasion, and metastasis of cancer cells. They are dysregulated in different types of malignancies and have the potential to serve as diagnostic markers for cancer. The expression of noncoding RNAs is altered following many diseases, and besides, some of them can be secreted from the cells into the circulation following the apoptotic and necrotic cell death. These secreted noncoding RNAs are known as cell free RNA. These RNAs can be secreted from the cell through the apoptotic body, extracellular vesicles including microvesicle and exosome, and bind to proteins. Since, lncRNAs display high organ and cell specificity, can be found in the blood, urine, tumor tissue, or other tissues or bodily fluids of some patients with cancer, this review summarizes the most significant and up-to-date findings of research on lncRNAs involvement in different cancers, focusing on the potential of cancer-related lncRNAs as biomarkers for diagnosis, prognosis, and therapy.

Upregulation of lncRNA snoRNA host gene 6 regulates NUAK family SnF1-like kinase-1 expression by competitively binding microRNA-125b and interacting with Snail1/2 in bladder cancer

BACKGROUNDS/AIMS

Numerous studies have reported that long noncoding RNAs (lncRNAs) play critical roles in the development and progression of bladder cancer (BC). LncRNA snoRNA host gene 6 (SNHG6) is ectopically expressed in tumor tissues of patients with BC and BC cell lines. However, little is known about the molecular mechanism of SNHG6-mediated bladder urothelial carcinoma cell migration and invasion.

METHODS

We detected the SNHG6 levels in human BC specimens and cell lines by quantitative real-time polymerase chain reaction and Western blot, and investigated its role in BC using in vitro assays.

RESULTS

We showed that overexpression of SNHG6 induced epithelial-mesenchymal transition (EMT) and promoted the migration and invasion capabilities of BC cells. Mechanistically, SNHG6 induced EMT of BC cells by upregulating the expression levels of Snail1/2 and regulated BC cell migration and invasion by tumor suppressive hsa-miR-125b and its target gene NUAK Family Kinase 1 (NUAK1). Furthermore, we found that SNHG6 was positively correlated with Snail1/2 expression, and negatively correlated with hsa-miR-125b expression in BC specimens. Further study showed that SNHG6 repressed hsa-miR-125b expression to upregulate Snail1/2. Conversely, hsa-miR-125b knockdown augmented SNHG6 expression in BC cells.

CONCLUSION

Overall, our study demonstrated that SNHG6 promotes BC cell migration and invasion partly via the hsa-miR-125b/Snail1/2/NUAK1 pathway. Therefore, SNHG6 may be a potential prognostic biomarker in BC, and targeting hsa-miR-125b/Snail1/2/NUAK1 axis may be a promising therapeutic approach for BC patients.

LncRNA SNHG6 promotes proliferation, invasion and migration in colorectal cancer cells by activating TGF-β/Smad signaling pathway via targeting UPF1 and inducing EMT via regulation of ZEB1

Background: Long noncoding RNAs (lncRNAs) are non-protein coding transcripts longer than 200 nucleotides in length. They drive many important cancer phenotypes through their interactions with other cellular macromolecules including DNA, RNA and protein. Recent studies have identified numerous lncRNAs active in colorectal cancer (CRC). The lncRNA small nucleolar RNA host gene 6 (SNHG6) has been reported to have an oncogenic role in multiple cancers. However, the biological role and mechanism of SNHG6 in the tumorigenesis of CRC has not been reported in-deep. Methods: The Cancer Genome Atlas (TCGA) database and GEO database were used to identify SNHG6 expression in different human cancers and explore the relationship between SNHG6 expression and patient prognosis using Kaplan-Meier method analysis. SNHG6 expression in 77 pairs of clinical CRC tissues and different CRC cell lines were analyzed by quantitative real-time PCR (qRT-PCR). A CCK-8 assay was used to assess cell proliferation, transwell assay to detect the cell metastasis, and tumor growth was investigated with a nude mice model in vivo. Whether UPF1 and ZEB1 are downstream targets of SNHG6 was verified by bioinformatics target gene prediction, qRT-PCR and western blot. Results: TCGA data showed that SNHG6 was significantly upregulated in colorectal cancer samples in comparison with healthy data samples (P < 0.01). CRC patients with high levels of SNHG6 had a significantly shorter overall survival than those with low levels of SNHG6 (P = 0.0162). qRT-PCR confirmed that the expression of SNHG6 was significantly upregulated in CRC tissues and cell lines. Upregulation of SNHG6 expression induced RKO and HCT116 cell proliferation as well as RKO cell metastasis, while downregulation of SNHG6 expression supressed the proliferation and metastasis of RKO cells and tumor growth in vivo. UPF1 was upregulated and ZEB1 was decreased when SNHG6 knockdown, regulating the TGF-β/Smad pathway and inducing EMT respectively. Conclusions: SNHG6 may play an oncogenic role in CRC cells by activating TGF-β/Smad signaling pathway via targeting of UPF1 and inducing EMT via regulating ZEB1. This could be a prognostic biomarker and therapeutic target for CRC.

Long non-coding RNA SNHG6 promotes glioma tumorigenesis by sponging miR-101-3p

INTRODUCTION

Glioma is the most common primary brain tumor. The small nucleolar RNA host gene (SNHG) SNHG6 is a potential oncogene in the development of several types of cancers.

METHODS

In this study, we investigated the functional role of long non-coding RNA (lncRNA) SNHG6 in the malignancy of glioma in cell lines and transplanted nude mice.

RESULTS

We found that the expression of lncRNA SNHG6 was higher in glioma tissues and cells than in normal brain tissues and cells. The expression of lncRNA SNHG6 was positively correlated with the malignancy and poor prognosis of glioma patients. microRNA (miR)-101-3p expression was decreased in glioma tissues and cells and was negatively correlated with the malignancy and poor prognosis of glioma patients. In glioma tissues, the expression of lncRNA SNHG6 was negatively correlated with the expression of miR-101-3p. SNHG6 contained a binding site of miR-101-3p. Knockdown of SNHG6 expression resulted in a significant increase of miR-101-3p expression. miR-101-3p mimic markedly decreased the luciferase activity of SNHG6. Knockdown of SNHG6 inhibited glioma cell proliferation, migration, and epithelial-mesenchymal transition (EMT), and increased apoptosis. miR-101-3p mimic enhanced knockdown of SNHG6-induced inhibition of cell proliferation, migration, and EMT, and an increase of apoptosis. Anti-miR-101-3p reversed the the effects of si-SNHG6 on cell malignancy. Knockdown of SNHG6 remarkably reduced the increase of tumor volumes in xenograft mouse models. In tumor tissues, knockdown of SNHG6 increased the expression of miR-101-3p and reduced EMT biomarker expression.

CONCLUSIONS

Our study provides novel insights into the functions of lncRNA SNHG6/miR-101-3p axis in the tumorigenesis of glioma.

Long non-coding RNAs expression levels in diffuse large B-cell lymphoma: An in silico analysis

Long non-coding RNAs (lncRNAs), are lengthy noncoding transcripts with pivotal roles in biological pathways including cell cycle, apoptosis and chromatin remodeling. Aberrant expression of lncRNAs has been strongly connected with tumor progression and metastasis. However, the prognostic significance of lncRNAs in diffuse large-B-cell lymphoma (DLBCL) remains unclear. In this study, the expression levels of 189 approved lncRNAs were considered in DLBCL patients using several different genomic and transcriptome datasets. The analyses showed that the lncRNA GAS5 allocated the maximum score of RNA dysregulation and can be considered as good choice in DLBCLs' researches.

Long Noncoding RNAs in Colorectal Adenocarcinoma; an in silico Analysis

Long noncoding RNAs (lncRNAs) are lengthy noncoding transcripts which are involved in critical signaling pathways including cell cycle and apoptosis so it is not surprising to see their altered expression in human tumors. Colorectal adenocarcinoma is one the most frequent malignancies worldwide. The role of lncRNAs in colorectal adenocarcinoma is not well understood. To study the significance of lncRNAs in colorectal adenocarcinoma, we retrieved 189 approved lncRNAs from HGNC. The genes were imported into the cBioPortal database for transcriptomic analyses. We queried all the samples from TCGA provisional colorectal adenocarcinoma with RNA-seq v2 data in our study and considered RNA dysregulation with Z-score: ±2. The lncRNA which was altered in most of the patients were considered as "significant lncRNA" for further analyses. We considered the association of candidate lncRNAs with clinicopathologic parameters of samples including tumor disease anatomic site, neoplasm histologic types, tumor stage and survival. We also compute the specificity of the significant lncRNAs expression in colorectal adenocarcinoma comparing with other human cancers in cancer portal. Our analysis showed that lncRNAs SNHG6, PVT1 and ZFAS1 allocated the maximum alteration among the colorectal cases. The expression of SNHG6 and ZFAS1 was more in rectal adenocarcinoma than the colon carcinoma while the PVT1 showed the same expression levels in both tissues. However, we found that upregulation of PVT1 has been reduced the overall survival in patients. Altogether these data showed SNHG6, PVT1 and ZFAS1, are promising candidates for experimental research on colorectal adenocarcinoma to discover novel biomarker for this prevalent cancer.

The Role of Long Non-Coding RNAs in Hepatocarcinogenesis

Whole-transcriptome analyses have revealed that a large proportion of the human genome is transcribed in non-protein-coding transcripts, designated as long non-coding RNAs (lncRNAs). Rather than being “transcriptional noise”, increasing evidence indicates that lncRNAs are key players in the regulation of many biological processes, including transcription, post-translational modification and inhibition and chromatin remodeling. Indeed, lncRNAs are widely dysregulated in human cancers, including hepatocellular carcinoma (HCC). Functional studies are beginning to provide insights into the role of oncogenic and tumor suppressive lncRNAs in the regulation of cell proliferation and motility, as well as oncogenic and metastatic potential in HCC. A better understanding of the molecular mechanisms and the complex network of interactions in which lncRNAs are involved could reveal novel diagnostic and prognostic biomarkers. Crucially, it may provide novel therapeutic opportunities to add to the currently limited number of therapeutic options for HCC patients. In this review, we summarize the current status of the field, with a focus on the best characterized dysregulated lncRNAs in HCC.

Behind the curtain of non-coding RNAs; long non-coding RNAs regulating hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is one of the most common and aggressive cancers worldwide. HCC is the fifth common malignancy in the world and the second leading cause of cancer death in Asia. Long non-coding RNAs (lncRNAs) are RNAs with a length greater than 200 nucleotides that do not encode proteins. lncRNAs can regulate gene expression and protein synthesis in several ways by interacting with DNA, RNA and proteins in a sequence specific manner. They could regulate cellular and developmental processes through either gene inhibition or gene activation. Many studies have shown that dysregulation of lncRNAs is related to many human diseases such as cardiovascular diseases, genetic disorders, neurological diseases, immune mediated disorders and cancers. However, the study of lncRNAs is challenging as they are poorly conserved between species, their expression levels aren't as high as that of mRNAs and have great interpatient variations. The study of lncRNAs expression in cancers have been a breakthrough as it unveils potential biomarkers and drug targets for cancer therapy and helps understand the mechanism of pathogenesis. This review discusses many long non-coding RNAs and their contribution in HCC, their role in development, metastasis, and prognosis of HCC and how to regulate and target these lncRNAs as a therapeutic tool in HCC treatment in the future.

A long non-coding RNA expression signature to predict survival of patients with colon adenocarcinoma

Colon cancer is the most common type of gastrointestinal cancer and is still the leading cause of cancer-related mortality worldwide. Long non-coding RNAs (lncRNAs) have been proved to be superior biomarkers in cancer diagnosis and prognosis than miRNAs and protein-coding genes. In the current study, our objective was to detect novel lncRNA biomarkers by analyzing lncRNA expression profiles and clinical data in a large cohort of patients with colon patients from The Cancer Genome Atlas (TCGA). By using Cox regression analysis, we identified two lncRNAs (SNHG6 and CTD-2354A18.1) which could be independent prognostic factors for predicting clinical outcome in colon adenocarcinoma. Then a linear combination of these two lncRNA biomarkers (SNHG6 and CTD-2354A18.1), termed two-lncRNA signature, was developed in the training set as a predictor for OS in patients with colon adenocarcinoma, and validated in the testing set and the entire patient set. This two-lncRNA signature demonstrated significant prognostic performance in both the testing set and the entire patient set which classified the patients into two groups with significantly different OS. The multivariate and stratified analysis suggested that the prognostic value of the two-lncRNA signature was independent of other traditional clinical variables. Functional analysis suggested that these two lncRNA biomarkers might be mainly involved in transcription/translation-related or DNA repair-related biological processes. In summary, our results warrant further studies on these lncRNAs that will improve our understanding of the mechanisms associated with pathogenesis and progression of colon adenocarcinoma.