The Long Non-Coding RNA RHPN1-AS1 Promotes Uveal Melanoma Progression

Evaluation of Clinically Significant miRNAs Level by Machine Learning Approaches Utilizing Total Transcriptome Data

Analysis of the mechanisms underlying the occurrence and progression of cancer represents a key objective in contemporary clinical bioinformatics and molecular biology. Utilizing omics data, particularly transcriptomes, enables a detailed characterization of expression patterns and post-transcriptional regulation across various RNA types relative to the entire transcriptome. Here, we assembled a dataset comprising transcriptomic data from approximately 16 000 patients encompassing over 160 types of cancer. We employed state-of-the-art gradient boosting algorithms to discern intricate correlations in the expression levels of four clinically significant microRNAs, specifically, hsa-mir-21, hsa-let-7a-1, hsa-let-7b, and hsa-let-7i, with the expression levels of the remaining 60 660 unique RNAs. Our analysis revealed a dependence of the expression levels of the studied microRNAs on the concentrations of several small nucleolar RNAs and regulatory long noncoding RNAs. Notably, the roles of these RNAs in the development of specific cancer types had been previously established through experimental evidence. Subsequent evaluation of the created database will facilitate the identification of a broader spectrum of overarching dependencies related to changes in the expression levels of various RNA classes in diverse cancers. In future, it will make possible to discover unique alterations specific to certain types of malignant transformations.

Tumor-infiltrating macrophage associated lncRNA signature in cutaneous melanoma: implications for diagnosis, prognosis, and immunotherapy

Along with the increasing knowledge of long noncoding RNA, the interaction between the long noncoding RNA (lncRNA) and tumor immune infiltration is increasingly valued. However, there is a lack of understanding of correlation between regulation of specific lncRNAs and tumor-infiltrating macrophages within melanoma. In this research, a macrophage associated lncRNA signature was identified by multiple machine learning algorithms and the robust and effectiveness of signature also validated in other independent datasets. The signature contained six specific lncRNAs (PART1, LINC00968, LINC00954, LINC00944, LINC00518 and C20orf197) was constructed, which could diagnose melanoma and predict the prognosis of patients. Moreover, our signature achieves higher accuracy than the previous well-established markers and regarded as an independent prognostic indicator. The pathway enrichment revealed that these lncRNAs were closely correlated with many immune processes. In addition, the signature was associated with different immune microenvironment and applied to predict response of immune checkpoint inhibitor therapy (low risk of patients well respond to anti-PD-1 therapy and high risk is insensitive to anti-CTLA-4 therapy). Therefore, our finding supplies a more accuracy and effective lncRNA signature for tumor-infiltrating macrophages targeting treatment approaches and affords a new clinical application for predicting the response of immunotherapies in melanomas.

From diagnosis to therapy: The transformative role of lncRNAs in eye cancer management

The genomic era has brought about a transformative shift in our comprehension of cancer, unveiling the intricate molecular landscape underlying disease development. Eye cancers (ECs), encompassing diverse malignancies affecting ocular tissues, pose distinctive challenges in diagnosis and management. Long non-coding RNAs (lncRNAs), an emerging category of non-coding RNAs, are pivotal actors in the genomic intricacies of eye cancers. LncRNAs have garnered recognition for their multifaceted roles in gene expression regulation and influence on many cellular processes. Many studies support that the lncRNAs have a role in developing various cancers. Recent investigations have pinpointed specific lncRNAs associated with ECs, including retinoblastoma and uveal melanoma. These lncRNAs exert control over critical pathways governing tumor initiation, progression, and metastasis, endowing them with the ability to function as evaluation, predictive, and therapeutic indicators. The article aims to synthesize the existing information concerning the functions of lncRNAs in ECs, elucidating their regulatory mechanisms and clinical significance. By delving into the lncRNAs' expanding relevance in the modulation of oncogenic and tumor-suppressive networks, we gain a deeper understanding of the molecular complexities intrinsic to these diseases. In our exploration of the genomic intricacies of ECs, lncRNAs introduce a fresh perspective, providing an opportunity to function as clinical and therapeutic indicators, and they also have therapeutic benefits that show promise for advancing the treatment of ECs. This comprehensive review bridges the intricate relationship between lncRNAs and ECs within the context of the genomic era.

Roles, biological functions, and clinical significances of RHPN1-AS1 in cancer

For the complex and multifaceted challenge of cancer eradication, a comprehensive approach is required. Molecular strategies are critical in the fight against cancer as they allow us to understand the underlying fundamental mechanisms and develop specialized treatments. The role of long non-coding RNAs (lncRNAs), a class of ncRNA molecules longer than 200 nucleotides, in cancer biology has attracted growing attention in recent years. These roles include but are not limited to regulating gene expression, protein localization, and chromatin remodeling. LncRNAs can influence a range of cellular functions and pathways, including those involved in cancer development. The first study on RHPN1 antisense RNA 1 (RHPN1-AS1), a 2030-bp transcript originating from human chromosome 8q24, in uveal melanoma (UM) demonstrated that this lncRNA was significantly upregulated in several UM cell lines. Further studies in various cancer cell lines showed that this lncRNA is significantly overexpressed and exerts oncogenic functions. This review will provide an overview of current knowledge regarding the roles played by RHPN1-AS1 in the emergence of various cancers, focusing on its biological and clinical functions.

Retracted: Long noncoding RNA RHPN1-AS1, induced by KDM5B, is involved in breast cancer via sponging miR-6884-5p

The above article, published online in Journal of Cellular Biochemistry on 31 January 2020 in Wiley Online Library (https://doi.org/10.1002/jcb.29645), has been retracted by agreement between the authors, the journal's Editor in Chief, Prof. Dr. Christian Behl, and Wiley Periodicals LLC. The authors asked to retract their article after substantial mistakes in experimental data were found, thus the results are considered to be invalid.

Genetics and RNA Regulation of Uveal Melanoma

Uveal melanoma (UM) is the most common intraocular malignant tumor and the most frequent melanoma not affecting the skin. While the rate of UM occurrence is relatively low, about 50% of patients develop metastasis, primarily to the liver, with lethal outcome despite medical treatment. Notwithstanding that UM etiopathogenesis is still under investigation, a set of known mutations and chromosomal aberrations are associated with its pathogenesis and have a relevant prognostic value. The most frequently mutated genes are BAP1, EIF1AX, GNA11, GNAQ, and SF3B1, with mutually exclusive mutations occurring in GNAQ and GNA11, and almost mutually exclusive ones in BAP1 and SF3B1, and BAP1 and EIF1AX. Among chromosomal aberrations, monosomy of chromosome 3 is the most frequent, followed by gain of chromosome 8q, and full or partial loss of chromosomes 1 and 6. In addition, epigenetic mechanisms regulated by non-coding RNAs (ncRNA), namely microRNAs and long non-coding RNAs, have also been investigated. Several papers investigating the role of ncRNAs in UM have reported that their dysregulated expression affects cancer-related processes in both in vitro and in vivo models. This review will summarize current findings about genetic mutations, chromosomal aberrations, and ncRNA dysregulation establishing UM biology.

Emerging Roles and Mechanisms of lncRNA FOXD3-AS1 in Human Diseases

Numerous long noncoding RNAs (lncRNAs) have been identified as powerful regulators of human diseases. The lncRNA FOXD3-AS1 is a novel lncRNA that was recently shown to exert imperative roles in the initialization and progression of several diseases. Emerging studies have shown aberrant expression of FOXD3-AS1 and close correlation with pathophysiological traits of numerous diseases, particularly cancers. More importantly, FOXD3-AS1 was also found to ubiquitously impact a range of biological functions. This study aims to summarize the expression, associated clinicopathological features, major functions and molecular mechanisms of FOXD3-AS1 in human diseases and to explore its possible clinical applications.

Regulation of epigenetic homeostasis in uveal melanoma and retinoblastoma

Uveal melanoma (UM) and retinoblastoma (RB), which cause blindness and even death, are the most frequently observed primary intraocular malignancies in adults and children, respectively. Epigenetic studies have shown that changes in the epigenome contribute to the rapid progression of both UM and RB following classic genetic changes. The loss of epigenetic homeostasis plays an important role in oncogenesis by disrupting the normal patterns of gene expression. The targetable nature of epigenetic modifications provides a unique opportunity to optimize treatment paradigms and establish new therapeutic options for both UM and RB with these aberrant epigenetic modifications. We aimed to review the research findings regarding relevant epigenetic changes in UM and RB. Herein, we 1) summarize the literature, with an emphasis on epigenetic alterations, including DNA methylation, histone modifications, RNA modifications, noncoding RNAs and an abnormal chromosomal architecture; 2) elaborate on the regulatory role of epigenetic modifications in biological processes during tumorigenesis; and 3) propose promising therapeutic candidates for epigenetic targets and update the list of epigenetic drugs for the treatment of UM and RB. In summary, we endeavour to depict the epigenetic landscape of primary intraocular malignancy tumorigenesis and provide potential epigenetic targets in the treatment of these tumours.

LncRNA LINC00152 promotes oral squamous cell carcinoma growth via enhancing Upstream Transcription Factor 1 mediated Mitochondrial Ribosomal Protein L52 transcription

BACKGROUND

LINC00152 (long intergenic non-protein coding RNA 152) was identified as an oncogenic lncRNA in multiple cancers. In the current study, we aimed to explore the transcriptional profile of LINC00152 in oral squamous cell carcinoma (OSCC) and its regulations at the transcriptional level.

METHODS

Bioinformatic analysis was performed by extracting the OSCC subset from The Cancer Genome Atlas (TCGA)-Head and Neck Squamous Cell Carcinoma (HNSC). LINC00152 subcellular localization and its interacting transcriptional factors (TFs) were explored. Dual-luciferase assay and ChIP-qPCR were applied to study transcriptional regulation. In vitro and in-vivo tumor cell growth models were used for functional assays.

RESULTS

NR_024206.2 was the dominant isoform that accounts for 80% of all transcripts of LINC00152. LINC00152 upregulation was associated with unfavorable survival of patients with OSCC. LINC00152 knockdown significantly impaired OSCC cell growth in vitro and in vivo. RNA FISH assay confirmed nuclear and cytoplasmic distribution of LINC00152. It physically interacted with Upstream Transcription Factor 1 (USF1), a common transcription factor in mammalian cells. USF1 could bind to the promoter region of MRPL52 (Mitochondrial Ribosomal Protein L52) and activate its transcription. LINC00152 could enhance the binding, thereby indirectly elevating MRPL52 expression. USF1 or MRPL52 knockdown slowed the proliferation of OSCC cells and partly canceled LINC00152 mediated growth-promoting effects.

CONCLUSION

This study revealed a novel LINC00152-USF1/MRPL52 axis promoting OSCC tumor growth.

The Role of LncRNAs in Uveal Melanoma

Uveal melanoma (UM) is an intraocular cancer tumor with high metastatic risk. It is considered a rare disease, but 90% of affected patients die within 15 years. Non-coding elements (ncRNAs) such as long non-coding RNAs (lncRNAs) have a crucial role in cellular homeostasis maintenance, taking part in many critical cellular pathways. Their deregulation, therefore, contributes to the induction of cancer and neurodegenerative and metabolic diseases. In cancer, lncRNAs are implicated in apoptosis evasion, proliferation, invasion, drug resistance, and other roles because they affect tumor suppressor genes and oncogenes. For these reasons, lncRNAs are promising targets in personalized medicine and can be used as biomarkers for diseases including UM.

MiRNAs Correlate with HLA Expression in Uveal Melanoma: Both Up- and Downregulation Are Related to Monosomy 3

Simple Summary

Uveal melanoma (UM) is a rare ocular malignancy that often gives rise to metastases. Tumours with an inflammatory phenotype have an especially bad prognosis. As an increased HLA expression and the presence of tumour-infiltrating lymphocytes and macrophages may be regulated by miRNAs, we set out to investigate whether any miRNAs are associated with inflammatory parameters in this malignancy. Some miRNAs were increased in UM with a high HLA expression and high T cell numbers, while others were decreased, showing two opposing patterns; however, both patterns were related to the tumour’s chromosome 3/BAP1 status. We conclude that specific miRNAs are related to the inflammatory phenotype and that these are differentially expressed between disomy 3/BAP1-positive versus monosomy 3/BAP1-negative UM.

Abstract

MicroRNAs are known to play a role in the regulation of inflammation. As a high HLA Class I expression is associated with a bad prognosis in UM, we set out to determine whether any miRNAs were related to a high HLA Class I expression and inflammation. We also determined whether such miRNAs were related to the UM’s genetic status. The expression of 125 miRNAs was determined in 64 primary UM from Leiden. Similarly, the mRNA expression of HLA-A, HLA-B, TAP1, BAP1, and immune cell markers was obtained. Expression levels of 24 of the 125 miRNAs correlated with expression of at least three out of four HLA Class I probes. Four miRNAs showed a positive correlation with HLA expression and infiltration with leukocytes, 20 a negative pattern. In the first group, high miRNA levels correlated with chromosome 3 loss/reduced BAP1 mRNA expression, in the second group low miRNA levels. The positive associations between miRNA-22 and miRNA-155 with HLA Class I were confirmed in the TCGA study and Rotterdam cohort, and with TAP1 in the Rotterdam data set; the negative associations between miRNA-125b2 and miRNA-211 and HLA-A, TAP1, and CD4 were confirmed in the Rotterdam set. We demonstrate two patterns: miRNAs can either be related to a high or a low HLA Class I/TAP1 expression and the presence of infiltrating lymphocytes and macrophages. However, both patterns were associated with chromosome 3/BAP1 status, which suggests a role for BAP1 loss in the regulation of HLA expression and inflammation in UM through miRNAs.

Genome-Wide Screening Identifies Prognostic Long Noncoding RNAs in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common malignancy with a poor prognosis. Therefore, there is an urgent call for the investigation of novel biomarkers in HCC. In the present study, we identified 6 upregulated lncRNAs in HCC, including LINC01134, RHPN1-AS1, NRAV, CMB9-22P13.1, MKLN1-AS, and MAPKAPK5-AS1. Higher expression of these lncRNAs was correlated to a more advanced cancer stage and a poorer prognosis in HCC patients. Enrichment analysis revealed that these lncRNAs played a crucial role in HCC progression, possibly through a series of cancer-related biological processes, such as cell cycle, DNA replication, histone acetyltransferase complex, fatty acid oxidation, and lipid modification. Moreover, competing endogenous RNA (ceRNA) network analysis revealed that these lncRNAs could bind to certain miRNAs to promote HCC progression. Loss-of-function assays indicated that silencing of RHPN1-AS1 significantly suppressed HCC proliferation and migration. Though further validations are still needed, these identified lncRNAs could serve as valuable potential biomarkers for HCC prognosis.

RHPN1‑AS1 promotes ovarian carcinogenesis by sponging miR‑485‑5p and releasing TPX2 mRNA

Long non-coding RNAs (lncRNAs) play a crucial role in cancer development. However, researchers have yet to identify the underlying association between lncRNAs and ovarian cancer (OC). The aim of the present study was to examine the effect of lncRNA RHPN1-AS1 (RHPN1-AS1) on OC cells and tissues. Reverse transcriptase-quantitative PCR (RT-qPCR) was utilized to quantify RHPN1-AS1, miR-485-5p, and TPX2 mRNA expression in samples with OC. Luciferase-reporter assay, RNA immunoprecipitation (RIP) assay, and RNA pull-down assay were then employed to validate the target relationship among RHPN1-AS1, miR-485-5p and TPX2. Cell Counting Kit-8, BrdU, wound-healing, cell-adhesion, and flow cytometry assays were also employed to assess cell viability, proliferation, migration, adhesion and apoptosis, respectively, in SKOV3 and OVCAR3 cell lines. Findings revealed that RHPN1-AS1 demonstrated a higher expression level in OC cell lines and tissues. In addition, RHPN1-AS1 enhanced the adhesion, proliferation and migration of OC cell lines but decreased apoptosis of OC cells. It was also observed that the relationship between RHPN1-AS1 and miR-485-5p was negative and that RHPN1-AS1 could sponge miR-485-5p to regulate the proliferation, apoptosis, adhesion, and migration abilities of OC cells. Moreover, TPX2 was targeted by miR-485-5p and was significantly overexpressed in OC cell lines and tissues. Experimental investigations also revealed that TPX2 promoted the proliferation, adhesion, and migration of OC cells but suppressed the apoptosis of SKOV3 and OVCAR3 cells. In summary, RHPN1-AS1 played a tumor promotive role by sponging miR-485-5p to increase TPX2 expression in OC tumorigenesis.

The roles of long non-coding RNAs in ocular diseases

In recent years, lncRNAs have been shown to regulate gene expression at the epigenetic, transcriptional and translational level, thus exerting various functions in biological and pathological processes involving cell proliferation, apoptosis, cell cycle and immune response. An increasing number of researches have unveiled that lncRNAs are dysregulated in pathogenesis and the development of different ocular diseases, such as glaucoma, cataract, retinal disease and ocular tumors. Also, it has been reported that lncRNAs may exert significant roles in various ocular diseases. Here, we summarized the functions of lncRNAs on relevant ocular diseases and further clarified their mechanisms. Here, several previous studies with detailed information of lncRNAs which have been proved to be the diagnostic or prognostic biomarkers and potential therapeutic targets were included. Also, it is our hope to provide a thorough knowledge of the functions of lncRNAs in eye diseases and the methods by which lncRNAs can influence ocular diseases.

Integrative Analysis of Methylation and Copy Number Variations of Prostate Adenocarcinoma Based on Weighted Gene Co-expression Network Analysis

Prostate adenocarcinoma (PRAD) is the most pervasive carcinoma diagnosed in men with over 170,000 new cases every year in the United States and is the second leading cause of death from cancer in men despite its indolent clinical course. Prostate-specific antigen testing, which is the most commonly used non-invasive diagnostic method for PRAD, has improved early detection rates in the past decade, but its effectiveness for monitoring disease progression and predicting prognosis is controversial. To identify novel biomarkers for these purposes, we carried out weighted gene co-expression network analysis of the top 10,000 variant genes in PRAD from The Cancer Genome Atlas in order to identify gene modules associated with clinical outcomes. Methylation and copy number variation analysis were performed to screen aberrantly expressed genes, and the Kaplan-Meier survival and gene set enrichment analyses were conducted to evaluate the prognostic value and potential mechanisms of the identified genes. Cyclin E2 (CCNE2), rhophilin Rho GTPase-binding protein (RHPN1), enhancer of zeste homolog 2 (EZH2), tonsoku-like DNA repair protein (TONSL), epoxide hydrolase 2 (EPHX2), fibromodulin (FMOD), and solute carrier family 7 member (SLC7A4) were identified as potential prognostic indicators and possible therapeutic targets as well. These findings can improve diagnosis and disease monitoring to achieve better clinical outcomes in PRAD.

Dose-Dependent Carbon-Dot-Induced ROS Promote Uveal Melanoma Cell Tumorigenicity via Activation of mTOR Signaling and Glutamine Metabolism

Uveal melanoma (UM) is the most common intraocular malignant tumor in adults and has a low survival rate following metastasis; it is derived from melanocytes susceptible to reactive oxygen species (ROS). Carbon dot (Cdot) nanoparticles are a promising tool in cancer detection and therapy due to their unique photophysical properties, low cytotoxicity, and efficient ROS productivity. However, the effects of Cdots on tumor metabolism and growth are not well characterized. Here, the effects of Cdots on UM cell metabolomics, growth, invasiveness, and tumorigenicity are investigated in vitro and in vivo zebrafish and nude mouse xenograft model. Cdots dose-dependently increase ROS levels in UM cells. At Cdots concentrations below 100 µg mL-1, Cdot-induced ROS promote UM cell growth, invasiveness, and tumorigenicity; at 200 µg mL-1, UM cells undergo apoptosis. The addition of antioxidants reverses the protumorigenic effects of Cdots. Cdots at 25-100 µg mL-1 activate Akt/mammalian target of rapamycin (mTOR) signaling and enhance glutamine metabolism, generating a cascade that promotes UM cell growth. These results demonstrate that moderate, subapoptotic doses of Cdots can promote UM cell tumorigenicity. This study lays the foundation for the rational application of ROS-producing nanoparticles in tumor imaging and therapy.

lncRNA RHPN1-AS1 Serves as a Sponge for miR-3133 Modulating the Cell Proliferation of Retinoblastoma through JAK2

Purpose

To investigate the effects of lncRNA RHPN1-AS1 on retinoblastoma (RB) and further explore its underlying molecular mechanisms.

Methods

The expression of RHPN1-AS1, miR-3133, (JAK2), and signal transducer and activator of transcription 3 (STAT3) was detected by qRT-PCR. CCK-8, EDU, and flow cytometry assays were conducted to assess the proliferation activity and apoptosis of RB cells. Double fluorescein and RNA immunoprecipitation assays were performed to detect the interaction between RHPN1-AS1 and miR-3133 or miR-3133 and JAK2. Western blotting was performed to detect the expression of apoptosis-related proteins.

Results

In RB cells, RHPN1-AS1 was upregulated. Silencing RHPN1-AS1 inhibited the activity of RB cells and promoted apoptosis. The expressions of proapoptotic factors (Bax and p53) were increased, while antiapoptotic factors (Bcl-2 and Survivin) were suppressed in siRHPN1-AS1 groups. Furthermore, we predicted and verified that RHPN1-AS1 regulated RB progression by targeting miR-3133/JAK2. In addition, siRHPN1-AS1 also inhibited oncogene STAT3 protein expression.

Conclusion

lncRNA RHPN1-AS1 served as a sponge for miR-3133 to counteract miR-3133-mediated JAK2/STAT3 suppression, indicating that the lncRNA RHPN1-AS1 may be a potential therapeutic target for the treatment of RB.

Knockdown of Long Non-Coding RNA LOC100132707 Inhibits the Migration of Uveal Melanoma Cells via Silencing JAK2

Background/Objective

Although lots of long non-coding RNAs (lncRNAs) have been demonstrated to be involved in carcinogenesis, the functions of numerous of lncRNAs remain unknown. Bioinformatics online database showed that lncRNA LOC100132707 was highly expressed in metastatic melanoma tissues, and its expression predicted a lower overall survival rate in melanoma patients. However, LOC100132707 function in uveal melanoma (UM) progression still remains unclear. In the present study, we aimed to elucidate the role and molecular mechanisms underlying LOC100132707 in UM.

Methods

RT-PCR was used to detect the levels of LOC100132707 in UM cells. Cell migration, invasion and tumorigenesis were tested by using the transwell chamber assay and in vivo assay.

Results

LOC100132707 expression in metastatic UM cell line MM28 was significantly higher than that of the non-metastatic UM cell lines, MP38, MP46 and MP65, as well as the expressions of LOC100132707-related genes, including XRN1, PARP14, JAK2, DDX60, BUB1 and SAMD9L. LOC100132707 downregulation significantly repressed cell migration and invasion abilities, whereas overexpressing JAK2 rescued these effects. Consistently, upregulation of LOC100132707 induced significant increases in cell migration and invasion abilities via upregulating JAK2. In addition, silencing of LOC100132707 significantly repressed the in vivo tumor formation ability in UM cells.

Conclusion

This study reveals that silence of LOC100132707 represses the migration of UM via downregulating JAK2. The LOC100132707/JAK2 axis might serve as a potent target for the prevention and treatment of UM metastasis.

STAT1-induced upregulation of lncRNA RHPN1-AS1 predicts a poor prognosis of hepatocellular carcinoma and contributes to tumor progression via the miR-485/CDCA5 axis

Long noncoding RNAs (lncRNAs) act as a critical regulator in tumor progression, but few lncRNAs have been functionally characterized in hepatocellular carcinoma (HCC). Using The Cancer Genome Atlas datasets and bioinformatic technology, we screened and identified a novel HCC-related lncRNA, RHPN1 antisense RNA 1 (RHPN1-AS1). We found that the levels of RHPN1-AS1 were distinctly upregulated in both HCC tissues and cell lines. RHPN1-AS1 was activated by the transcription factor STAT1. Clinical investigations suggested that higher levels of RHPN1-AS1 were distinctly correlated with histologic grade, advanced tumor, node, metastasis stage, and poorer clinical prognosis. Multivariate assays identified high RHPN1-AS1 expression as an unfavorable prognostic biomarker for patients with HCC. Functional study revealed that knockdown of RHPN1-AS1 was able to suppress cells proliferation and metastasis, and promote cell apoptosis. Further mechanistic investigation suggested that RHPN1-AS1 could promote CDCA5 expressions by functioning as a competing endogenous RNA for miR-485. This interaction resulted in consequentially suppression of HCC cells proliferation, migration, and invasion. Our findings for the first time illustrate how RHPN1-AS1 displayed its tumor-promotive roles in HCC and may offer a new biomarker and a potential therapeutic target for patients with HCC.

LncRNA RHPN1-AS1 accelerates proliferation, migration, and invasion via regulating miR-485-5p/BSG axis in hepatocellular carcinoma

It is reported that long noncoding RNA RHPN1-AS1 (lncRNA RHPN1-AS1) functions as an oncogene among multiple types of cancers; however, the effect of lncRNA RHPN1-AS1 in hepatocellular carcinoma (HCC) is left to be investigated. The main purpose of this work was to study the effects of lncRNA RHPN1-AS1/miR-485-5p system on proliferation, migration, and invasion in HCC and future investigate the latent mechanisms. Our work found that lncRNA RHPN1-AS1 was observably up-regulated in HCC tissues and cell lines, especially HCCLM3 and SMMC-7721 cells. LncRNA RHPN1-AS1 knockdown decreased the capacity of proliferation, invasion, and migration in HCCLM3 and SMMC-7721 cells, which could be crippled by miR-485-5p inhibitor. Besides, the expression of basigin (BSG) was decreased after lncRNA RHPN1-AS1 silence, indicating the function of lncRNA RHPN1-AS1/miR-485-5p/BSG axis in HCC progression. Our study opens novel insights to help understand the mechanisms of lncRNA RHPN1-AS1/miR-485-5p/BSG axis in HCC progression, which may provide a new therapeutic target for HCC treatment.

Long Non-Coding RNA GAS5 Targeting microRNA-21 to Suppress the Invasion and Epithelial-Mesenchymal Transition of Uveal Melanoma

Objective

Human uveal melanoma (UM) is a common ocular malignant tumor with a high risk of metastasis. Emerging evidence indicates that long non-coding RNAs (lncRNAs) are correlated with the development of UM. Here, we aimed to determine the biological significance of lncRNA growth arrest-specific transcript 5 (GAS5) in UM.

Methods

The expression levels of GAS5 and microRNA-21 (miR-21) in UM tissues and cells were detected by qRT-PCR analysis. CCK-8 assay was performed to investigate the viability of UM cells after cell transfections, and the migration and invasion of UM cells were determined by transwell assay. The protein expression levels were detected by Western blot assay. The relationship between miR-21 and GAS5 in UM cells was confirmed by bioinformatics prediction and luciferase report assay.

Results

Our experiments demonstrated that GAS5 was markedly downregulated in UM cells and clinical specimens. Overexpression of GAS5 inhibited, whereas knockdown of GAS5 promoted the viability, migration, and invasion of UM cells. The epithelial-to-mesenchymal transition (EMT) process of UM cells was also suppressed by upregulating of GAS5 and enhanced by downregulating of GAS5. Additionally, as a competitive endogenous RNA (ceRNA), GAS5 directly binded to the oncogenic miR-21 in UM cells, and overexpression of miR-21 attenuated the EMT-suppressing effect of GAS5.

Conclusion

Taken together, our findings suggest that GAS5/miR-21 axis is implicated in the pathogenesis of UM and might serve as a potential therapeutic target.

The critical roles of lncRNAs in the pathogenesis of melanoma

Long non-coding RNAs (lncRNAs) embrace a huge fraction of human transcripts and participate in the pathogenesis of human disorders especially malignant conditions. Malignant melanoma, as the most fatal type of cutaneous malignnacies, is associated with dysregulation of several lncRNAs including PVT1, H19, MALAT1, and CCAT1. Moreover, a portion of lncRNAs are exclusively expressed in melanoma cell lines. Expression levels of several lncRNAs are associated with TNM stage, tumor size and progression of melanoma. Thus, these lncRNAs are regarded as biomarkers for this malignancy. Peripheral transcript levels of a number of lncRNAs, such as PVT1, SNHG5 and SPRY4-IT1, could distinguish melanoma patients from unaffected persons with appropriate sensitivity and specificity values. Moreover, expression levels of numerous lncRNAs in tissue biopsies could differentiate malignant samples from benign samples. Based on the results of both cell line and in vivo studies, lncRNAs regulate critical pathways in the carcinogenesis of melanoma, such as the PI3K/Akt and NF-κB signaling pathways, and are involved in the modulation of response to chemotherapeutic agents. Here we review the existing information on the role of lncRNAs in malignant melanoma.

The Role of Non-Coding RNAs in Uveal Melanoma

Simple Summary

The development of uveal melanoma is a multifactorial and multi-step process, in which abnormal gene expression plays a key role. Recently, several studies have highlighted the role of non-coding RNAs in the progression of uveal melanoma by affecting different signaling pathways. As important agents in the regulation of genes, non-coding RNAs have enormous potential to open up therapeutic pathways, predict response to treatment, and anticipate patient outcome for uveal melanoma. This review aims to provide a comprehensive view of what we know about ncRNAs in uveal melanoma currently.

Abstract

Uveal melanoma (UM) is the most common primary intraocular tumor in adulthood. Approximately 50% of patients develop metastatic disease, which typically affects the liver and is usually fatal within one year. This type of cancer is heterogeneous in nature and is divided into two broad groups of tumors according to their susceptibility to develop metastasis. In the last decade, chromosomal abnormalities and the aberrant expression of several signaling pathways and oncogenes in uveal melanomas have been described. Recently, importance has been given to the association of the mentioned deregulation with the expression of non-coding RNAs (ncRNAs). Here, we review the different classes of ncRNAs—such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs)—and their contribution to the development of UM. Special attention is given to miRNAs and their regulatory role in physiopathology and their potential as biomarkers. As important agents in gene regulation, ncRNAs have a huge potential for opening up therapeutic pathways, predicting response to treatment, and anticipating patient outcome for UM.

Integrated analysis identifies a long non-coding RNAs-messenger RNAs signature for prediction of prognosis in hepatitis B virus-hepatocellular carcinoma patients

Hepatitis B virus (HBV) infection is a leading cause of hepatocellular carcinoma (HCC), but HBV-HCC related prognosis signature remains rarely investigated. This study was to identify an integrated long non-coding RNAs-messenger RNAs (lncRNA-mRNA) signature for prediction of overall survival (OS) and explore their underlying functions.One RNA-sequencing dataset (training set, n = 95) and one microarray dataset E-TABM-36 (validation set, n = 44) were collected. Least absolute shrinkage and selection operator analysis was performed to identify an lncRNA-mRNA prognosis signature. The OS difference of patients in the high-risk and low-risk risk groups was evaluated by Kaplan-Meier curve. Area under the receiver operating characteristic curve (AUC), Harrell concordance index (C-index) calculation, and multivariate analyses with clinical characteristics were used to determine the prognostic ability. Furthermore, a coexpression network was constructed to interpret the functions.Nine signature genes (3 lncRNAs and 6 mRNAs) were selected to generate the risk score model. Patients belonging to the high-risk group showed a significantly shorter survival than those of the low-risk group. The prediction accuracy of the risk score for 5-year OS was 0.936 and 0.905 for the training set and validation set, respectively. Also, this risk score was independent of various clinical variables for the prognosis prediction. Incorporation of the risk score remarkably increased the predictive power of the routine clinical prognostic factors (vascular invasion status, tumor recurrence status) (AUC = 0.942 vs 0.628; C-index = 0.7997 vs 0.6908). Furthermore, LncRNA insulin-like growth factor 2 antisense RNA (IGF2-AS) and long intergenic non-protein coding RNA 342 (LINC00342) were predicted to exert tumor suppression effects by regulating homeobox D1 (HOXD1) and secreted frizzled related protein 5 (SFRP5), respectively; while lncRNA rhophilin Rho GTPase binding protein 1 antisense RNA 1 (RHPN1-AS1) may possess carcinogenic potential by promoting the transcription of chromobox 2 (CBX2), cell division cycle 20 (CDC20), matrix metallopeptidase 12 (MMP12), stratifin (SFN), tripartite motif containing 16 (TRIM16), and uroplakin 3A (UPK3A). These mRNAs may be associated with cell proliferation or apoptosis related pathways.This study may provide a novel, effective prognostic biomarker, and some therapeutic targets for HBV-HCC patients.

RHPN1-AS1 Drives the Progression of Hepatocellular Carcinoma via Regulating miR-596/IGF2BP2 Axis

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most deadly cancer types worldwide, and its incidence is high in China. Multiple long non-coding RNAs (lncRNAs) have been recently identified as crucial oncogenic factors or tumor suppressors. In this study, we explored the effects of LncRNA RHPN1 antisense RNA 1 (RHPN1-AS1) on the progression of HCC.

METHODS

Expression levels of RHPN1-AS1 and miR-596 in HCC samples were measured by qRT-PCR. The association between pathological indexes and the expression level of RHPN1-AS1 was also analyzed. Human HCC cell lines Huh7 and SMMC-7721 were used as cell models. CCK-8 and colony formation assays were performed to assess the effect of RHPN1-AS1 on HCC cell line proliferation. The flow cytometer instrument was used to study the effect of RHPN1-AS1 on apoptosis of HCC cells. The transwell assay was conducted to detect the effect of RHPN1-AS1 on migration and invasion. Furthermore, luciferase reporter assay was used to confirm targeting of miR-596 by RHPN1-AS1. Additionally, the regulatory function of RHPN1-AS1 on insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) was detected by western blot.

RESULTS

The expression level of RHPN1-AS1 in HCC samples was observed to significantly increase compared with normal tissues and its high expression was correlated with unfavorable pathological indexes. Highly expressed RHPN1-AS1 was associated with shorter overall survival time. RHPN1-AS1 overexpression remarkably accelerated proliferation and metastasis of HCC cells, while reduced apoptosis. Accordingly, RHPN1-AS1 knockdown suppressed the malignant phenotypes of HCC cells. RHPN1-AS1 overexpression significantly reduced miR-596 expression by sponging it, but enhanced IGF2BP2 expression.

CONCLUSION

RHPN1-AS1 acts as a sponge of tumor suppressor miR-596 in HCC that can indirectly enhance the IGF2BP2 expression and function as an oncogenic lncRNA.

LncRNA RHPN1-AS1 Promotes Cell Proliferation, Migration and Invasion Through Targeting miR-7-5p and Activating PI3K/AKT/mTOR Pathway in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a severe disease with high mortality in the world. Emerging evidence has suggested that lncRNAs play an important role in cancer progression, including HCC. This study aimed to comprehensively investigate the effect of lncRNA RHPN1 antisense RNA 1 (RHPN1-AS1) on HCC and its underlying molecular mechanism. In this study, we evaluated the expressions of lncRNA RHPN1-AS1 and miR-7-5p by qRT-RCR in both HCC tissue and HCC cells. Our findings showed that lncRNA RHPN1-AS1 was upregulated in HCC tissue and HCC cells, while miR-7-5p was downregulated. LncRNA RHPN1-AS1 expression in HCC patients was closely related to vascular invasion, tumor-node-metastasis (TNM) stage and barcelona clinic liver cancer (BCLC) stage. Furthermore, we quantified cell clone-formation ability, proliferation, migration and invasion of HCCLM3 and MHCC97 H cells using several assays (colony formation assay, 5-Ethynyl-2′-deoxyuridine (EdU) assay and transwell assay, respectively). Functional experiments confirmed that silencing lncRNA RHPN1-AS1 inhibited cell proliferation, migration and invasion in HCCLM3 and MHCC97 H cells. After that, bioinformatics analysis, dual luciferase reporter gene assay, qRT-PCR and western blot were used to investigate the molecular mechanism of lncRNA RHPN1-AS1 on HCC. Mechanistically, the rescue experiments demonstrated that miR-7-5p inhibitor reversed the inhibition effect of silencing lncRNA RHPN1-AS1 on HCCLM3 cells proliferation, migration and invasion. Moreover, silencing lncRNA RHPN1-AS1 also inhibited the activation of PI3K/AKT/mTOR pathway. Taken together our findings demonstrated that lncRNA RHPN1-AS1 could facilitate cell proliferation, migration and invasion via targeting miR-7-5p and activating PI3K/AKT/mTOR pathway in HCC.

Prognostic potential of lncRNA RHPN1-AS1 in glioma

Expression level of long non-coding RNA (lncRNA) RHPN1-AS1 in glioma tissues was detected to determine potential risk factors influencing prognosis of glioma. This study aimed to clarify the molecular mechanisms underlying tumorigenesis of glioma and thus to improve therapeutic efficacy of glioma. RHPN1-AS1 levels in glioma tissues (n=105) and normal brain tissues (n=105) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between RHPN1-AS1 level and pathological indicators of glioma patients was analyzed. Glioma patients were followed up for 5 years. Overall survival (OS) and relapse-free survival (RFS) in glioma patients were tested by Kaplan-Meier and log-rank method. Potential factors influencing prognosis of glioma were analyzed by Cox regression model. RHPN1-AS1 was upregulated in glioma tissues. Its level was correlated to histological grade, Karnofsky (KPS) score and postoperative recurrence of glioma patients, rather than sex, age, pathological and tumor size. Glioma patients expressing high level of RHPN1-AS1 suffered worse OS and RFS than those with low level. Advanced histological grade, KPS score <80 and high level of RHPN1-AS1 were considered to be risk factors influencing postoperative prognosis of glioma. High level of RHPN1-AS1 is an independent risk factor for poor prognosis of glioma, which may be utilized as a prognostic hallmark.

Long non‑coding RNA NONHSAT143692.2 is involved in oxidative DNA damage repair in the lens by regulating the miR‑4728‑5p/OGG1 axis

Age-related cataract (ARC) is the leading cause of blindness worldwide. Oxidative DNA damage is a biochemical feature of ARC pathogenesis. The present study investigated the role of long non-coding RNAs in the DNA repair of oxidative damage, partially the regulation of the DNA repair gene, 8-oxoguanine DNA glycosylase (OGG1), in lens affected by ARC. The ogg1 mutant zebrafish model was constructed to verify the role of ogg1 in the lens. A high-throughput lncRNA profiling was performed on human lens epithelial cells (LECs) following oxidative stress. The lncRNAs with the OGG1 target gene were analyzed for possible differentiated expression levels. The lens capsule samples of patients with ARC were collected to further verify the screening results. lncRNA was then overexpressed and knocked down in LECs to observe cell proliferation and apoptosis. The association between lncRNA, miRNA and the OGG1 mRNA 3′UTR were analyzed. The ogg1 mutant zebrafish developed more severe lens lesions following oxidative challenge. lncRNA NONHSAT143692.2 was distinctly expressed in various disease models. The knockdown of NONHSAT143692.2 downregulated the expression of OGG1 mRNA (P<0.001) and OGG1 protein (P<0.001), aggravated oxidative damage to LECs, increased apoptosis (P<0.001) and decreased cell proliferation (P<0.01). The overexpression of NONHSAT143692.2 reversed the above-mentioned outcomes. miR-4728-5p was predicted to bind to NONHSAT143692.2 and OGG1 mRNA 3′UTR. The overexpression of miR-4728-5p downregulated the expression of NONHSAT143692.2 (P<0.001), OGG1 mRNA (P<0.001) and OGG1 protein (P<0.001). The knockdown of miR-4728-5p reversed the above-mentioned outcomes. Overall, the findings of the present study demonstrate that the NONHSAT143692.2/miR-4728-5p/OGG1 axis may play an important role in the development of ARC. This novel concept may provide new insight into the molecular diagnosis and treatment of ARC.

Prognostic and Predictive Value of a Long Non-coding RNA Signature in Glioma: A lncRNA Expression Analysis

The current histologically based grading system for glioma does not accurately predict which patients will have better outcomes or benefit from adjuvant chemotherapy. We proposed that combining the expression profiles of multiple long non-coding RNAs (lncRNAs) into a single model could improve prediction accuracy. We included 1,094 glioma patients from three different datasets. Using the least absolute shrinkage and selection operator (LASSO) Cox regression model, we built a multiple-lncRNA-based classifier on the basis of a training set. The predictive and prognostic accuracy of the classifier was validated using an internal test set and two external independent sets. Using this classifier, we classified patients in the training set into high- or low-risk groups with significantly different overall survival (OS, HR = 8.42, 95% CI = 4.99–14.2, p < 0.0001). The prognostic power of the classifier was then assessed in the other sets. The classifier was an independent prognostic factor and had better prognostic value than clinicopathological risk factors. The patients in the high-risk group were found to have a favorable response to adjuvant chemotherapy (HR = 0.4, 95% CI = 0.25–0.64, p < 0.0001). We built a nomogram that integrated the 10-lncRNA-based classifier and four clinicopathological risk factors to predict 3 and 5 year OS. Gene set variation analysis (GSVA) showed that pathways related to tumorigenesis, undifferentiated cancer, and epithelial–mesenchymal transition were enriched in the high-risk groups. Our classifier built on 10-lncRNAs is a reliable prognostic and predictive tool for OS in glioma patients and could predict which patients would benefit from adjuvant chemotherapy.

lncRNA RHPN1-AS1 Promotes Ovarian Cancer Growth and Invasiveness Through Inhibiting miR-1299

Background

Ovarian cancer (OC) is a big threat for public health. However, the molecular mechanism underlying OC development and progression remains unclear. Although the importance of lncRNA in cancer has been proven, how lncRNA is involved in OC is waiting for further investigation.

Materials and Methods

qRT-PCR was performed to test expression level. CCK8 and colony formation were conducted to analyze proliferation. Transwell was conducted to measure migration and invasion. Luciferase reporter assay and pulldown assay were utilized to validate RNA interaction.

Results

lncRNA RHPN1-AS1 was highly expressed in OC tissues. RHPN1-AS1 was positively correlated with OC progression and its high expression indicated a low survival rate. Moreover, knockdown of RHPN1-AS1 significantly inhibited the proliferation, migration and invasion of OC cells, and bioinformatics analysis identified that miR-1299 was sponged by RHPN1-AS1 in OC cells. Knockdown of RHPN1-AS1 markedly promoted miR-1299 expression. Of note, inhibition of miR-1299 reversed the roles of RHPN1-AS1 silencing on suppressing proliferation, migration and invasion.

Conclusion

Our study demonstrates that RHPN1-AS1 promotes OC progression via sponging miR-1299, suggesting RHPN1-AS1 may be a novel therapeutic target.

RHPN1-AS1 promotes cell proliferation and migration via miR-665/Akt3 in ovarian cancer

Recent efforts have revealed that long non-coding RNAs exert crucial roles in cancer initiation and progression. RHPN1-AS1 is a 2030 bp transcript from human chromosome 8q24, and involved in tumorigenesis in uveal melanoma and non-small cell lung cancer, but it remains unknown in ovarian cancer. This study focused on the role of RHPN1-AS1 in ovarian cancer and found that RHPN1-AS1 was up-regulated in ovarian cancer tissues and cell lines. Overexpression of RHPN1-AS1 promoted ovarian cancer cell proliferation, migration, and invasion. Mechanistically, overexpression of RHPN1-AS1 decreased the expression of miR-665 and subsequently promoted the expression of Akt3 at posttranscriptional level. Taken together, RHPN1-AS1 positively regulated the expression of Akt3 through sponging miR-665, and exerted an oncogenic role in ovarian cancer progression, and indicates that RHPN1-AS1 may be a potential therapeutic target in ovarian cancer.

Long non-coding RNA RHPN1-AS1 promotes tumorigenesis and metastasis of ovarian cancer by acting as a ceRNA against miR-596 and upregulating LETM1

Background: In recent decades, long non-coding RNAs (lncRNAs) have been reported as crucial functional regulators involved in ovarian cancer. In the present study, we explored how lncRNA RHPN1-AS1 influences the progression of epithelial ovarian cancer (EOC) through tumor cell-dependent mechanisms.

Results: The expression of RHPN1-AS1 in EOC tissues was higher than that in para-cancerous control tissues. High expression of RHPN1-AS1 was closely associated with poor prognosis in EOC patients. N6-methyladenosine (m6A) improved the stability of RHPN1-AS1 methylation transcript by reducing RNA degradation, which resulted in upregulation of RHPN1-AS1 in EOC. In vitro and in vivo functional experiments showed that RHPN1-AS1 promoted EOC cell proliferation and metastasis. RHPN1-AS1 acted as a ceRNA to sponge miR-596, consequently increasing LETM1 expression and activating the FAK/PI3K/Akt signaling pathway.

Conclusion: RHPN1-AS1-miR-596-LETM1 axis plays a crucial role in EOC progression. Our findings may provide promising drug targets for EOC treatment.

Methods: We determined the aberrantly expressed lncRNAs in EOC via microarray analysis and validated RHPN1-AS1 expression by qRT-PCR. The RHPN1-AS1-miR-596-LETM1 axis was examined by dual-luciferase reporter assay and RIP assay. The mechanism of RHPN1-AS1 was investigated through gain- and loss-of-function studies both in vivo and in vitro.

Long Noncoding RNA PVT1 Silencing Prevents the Development of Uveal Melanoma by Impairing MicroRNA-17-3p-Dependent MDM2 Upregulation

Purpose

Uveal melanoma is a common primary intraocular malignancy accompanied by high mortality. Previous evidence has highlighted the implication of microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) in uveal melanoma. Accordingly, we further uncovered the possible role of lncRNA plasmacytoma variant translocation 1 gene (PVT1) and microRNA-17-3p (miR-17-3p) in uveal melanoma.

Methods

A series of experiments were performed to examine the relationship among lncRNA PVT1, miR-17-3p, and murine double minute clone 2 oncoprotein (MDM2). Afterward, gain- and loss-of-function approaches were used with uveal melanoma cells to verify the role of lncRNA PVT1, miR-17-3p, and MDM2 in the tumorigenesis and development of uveal melanoma.

Results

Highly expressed lncRNA PVT1 and MDM2, yet lowly expressed miR-17-3p, were identified in ocular uveal melanoma tissues versus normal adjacent tissues. Then, dual luciferase reporter gene assay, RNA binding protein immunoprecipitation, and RNA pull-down assays showed that lncRNA PVT1 specifically bound to miR-17-3p, and that MDM2 was a target gene of miR-17-3p. Gain- and loss-of-function studies elucidated that silencing of lncRNA PVT1 or overexpression of miR-17-3p resulted in decreased MDM2 expression and increased transcriptional activity of p53, in addition to inhibiting uveal melanoma cell proliferation, migration, and invasion, yet promoted cell apoptosis in vitro. In addition, lncRNA PVT1 silencing or miR-17-3p overexpression was noted to inhibit tumor growth in vivo.

Conclusions

Downregulation of lncRNA PVT1 could potentially promote miR-17-3p expression to suppress tumorigenesis and development of uveal melanoma by activating the p53 signaling pathway through binding to MDM2.

The positive feedback loop of RHPN1-AS1/miR-1299/ETS1 accelerates the deterioration of gastric cancer

Gastric cancer (GC) is the most prevailing malignant tumor of digestive tract and accounts for a considerable part of cancer-relevant deaths worldwide. An increasing number of literatures highlight the important role of lncRNAs in the occurrence and development of GC. Considering that the function of RHPN1-AS1 in GC remains to be fully inquired, we purposed to investigate the potential and mechanism of RHPN1-AS1 in GC. The expression of RHPN1-AS1 was significantly upregulated in GC samples and cells. High RHPN1-AS1 level was strongly correlated with advanced stages of GC and predicted poor outcomes of GC. Furthermore, depletion of RHPN1-AS1 inhibited cell proliferation and cell cycle whereas promoted cell apoptosis. Subcellular fractionation analysis expounded the main expression of RHPN1-AS1 in GC cell cytoplasm. Herein, we conjectured that RHPN1-AS1 might exert its performance in GC through the ceRNA network. Our findings demonstrated that RHPN1-AS1 enhanced ETS1 expression via sponging miR-1299. More importantly, the transcriptional activation of RHPN1-AS1 was mediated by ETS1. Results of recue assays validated that RHPN1-AS1/miR-1299/ETS1 positive feedback loop aggravated the malignant behaviors of GC, revealing RHPN1-AS1 as a latent effective target for the treatment of GC patients.

lncRNA SNHG7 affects malignant tumor behaviors through downregulation of EZH2 in uveal melanoma cell lines

Previous studies have demonstrated that the long non-coding RNA, small nucleolar RNA host gene 7 (SNHG7) plays an important role in several types of cancer; however, its role in the development of uveal melanoma (UM) remains unclear. The present study investigated the effect of SNHG7 on the prognosis of UM, as well as on cell proliferation, cell cycle and apoptosis of UM cell lines. Furthermore, the present study aimed to determine the molecular mechanisms underlying these effects. The association between SNHG7 and prognosis of UM was analyzed using detailed SNHG7 mRNA expression data and clinical information from The Cancer Genome Atlas database. Reverse transcription-quantitative PCR was used in order to detect the differential expression of SNHG7 in UM tissues and cell lines. Cell proliferation was detected using Cell Counting Kit-8 assays, following overexpression of SNHG7. A cell cycle assay was performed using propidium iodide/RNase staining. An apoptosis assay was performed using the Annexin-V-Fluorescein isothiocyanate apoptosis detection kit. The expression of enhancer of zeste homolog 2 (EZH2) was measured via western blotting. The results of the present study indicated that low expression of SNHG7 was associated with poor prognosis. Furthermore, increasing the expression of SNHG7 inhibited the proliferation of UM cells, suppressed cell cycle progression and promoted apoptosis. Western blot analysis results revealed that overexpression of SNHG7 downregulated EZH2 protein expression levels in UM cell lines. The results of the present study demonstrated that SNHG7 inhibited malignant transformation of UM cells by regulating EZH2 expression.

Long Non-coding RNA LINC-PINT Suppresses Cell Proliferation and Migration of Melanoma via Recruiting EZH2

Long non-coding RNAs (lncRNAs) have been identified as crucial regulators in many human cancers. Many lncRNAs show aberrant expression in cancer, and some of them play critical roles in tumor proliferation, invasion, and metastasis. However, the regulatory functions of lncRNAs in melanoma progression remain to be elucidated. We utilized the Real-time PCR methodology to determine the expression of LINC-PINT in melanoma cell lines. To evaluate the effect of LINC-PINT on tumorigenesis of melanoma, we used Cell Counting Kit-8 (CCK8) and colony formation assay. Flow cytometry assay was used to detect the function of LINC-PINT on cell cycle status. PINT-interacting proteins were identified by chromatin isolation using RNA purification (ChIRP). Microarray assay and bioinformatics analysis were used to find the potential target genes of LINC-PINT and the status of LINC-PINT target gene candidate was verified using chromatin immunoprecipitation assay (ChIP). LINC-PINT plays a role in suppressing the tumorigenicity of melanoma, which was further determined by xenograft model assay. LINC-PINT was significantly downregulated in melanoma tissues and cell lines. The overexpression of LINC-PINT in tumor cells resulted in significant tumor growth reduction and migration inhibition in A375, Mum2B and CRMM1 cells. Results based on the in vivo xenograft model were further consistent with the in vitro findings that LINC-PINT impeded growth and metastasis of melanoma cells. Microarray assay and bioinformatics analysis indicated that CDK1, CCNA2, AURKA, and PCNA were potential targets of LINC-PINT. In conclusion, LINC-PINT inhibits the tumorigenicity of melanoma through recruiting EZH2 to the promoter of its target genes, leading to H3K27 trimethylation and epigenetic silencing of target genes. LINC-PINT may serve as a novel diagnostic and therapeutic target for melanoma.

LncRNA RHPN1-AS1 Targeting miR-625/REG3A Promotes Cell Proliferation And Invasion Of Glioma Cells

Introduction

Glioma arises from the proliferation of neuroglial cells differentiated from the ectoderm. Evidence has confirmed that differentially expressed long non-coding RNAs (lncRNAs) may be involved in the development and progression of various tumors. The present study aimed to explore the biological function of lncRNA RHPN1-AS1 in glioma.

Materials and methods

The expressions of RHPN1-AS1 in glioma tissues and cells were examined using RT-PCR. Colony formation assay, MTT assay, wound healing assay and transwell assay were performed to detect cell cloning efficiency, proliferation, migration and invasion of glioma cells, respectively. Western blot was applied to assess the expression levels of migration-related and invasion-related proteins. Online bioinformatic tools and luciferase reporter assay were, respectively, employed to predict and verify the downstream target microRNA/gene of RHPN1-AS1.

Results

RHPN1-AS1 was up-regulated in glioma tissues and cells. The cell proliferation, migration and invasion of glioma were inhibited when the expression of RHPN1-AS1 was down-regulated in glioma cells. The expressions of migration-related and invasion-related proteins were also suppressed in siRHPN1-AS1 groups. Furthermore, we predicted and verified that RHPN1-AS1 was directly targeted to miR-625-5p/REG3A. Our study demonstrated that the knockdown of RHPN1-AS1 inhibited the proliferation, migration and invasion activity of glioma cells via regulating miR-625-5p/REG3A expression.

Conclusion

The results revealed that the lncRNA RHPN1-AS1 may be a molecular target in glioma therapy.

Long non-coding RNA SNHG3 promotes progression of gastric cancer by regulating neighboring MED18 gene methylation

To understand the mechanistic involvement of long non-coding RNA (lncRNA) SNHG3 in gastric cancer (GC), the relative abundance of SNHG3 was determined by real-time PCR. Overall and metastasis-free survival was analyzed by Kaplan–Meier’s plot. The potential impact of SNHG3 on tumor progression was evaluated both in vitro and in vivo. The in vivo metastasis was monitored in the tail vein-injected mice. Our data suggested that high SNHG3 associated with unfavorable prognosis in respect to overall and metastasis-free survival. SNHG3-deficiency significantly suppressed cell proliferation and cell viability in vitro and xenograft progression in vivo. In addition, ectopic overexpression of SNHG3 promoted cell migration and invasion in vitro and lung metastasis in vivo. Mechanistically, we uncovered SNHG3 associated with EZH2 and negatively regulated MED18 expression through methylation modulation. Transient knockdown of MED18 in SNHG3-deficient cells completely rescued the tumor suppressive phenotypes in GC cells. Our data unraveled the oncogenic properties of high SNHG3 in GC, which predominantly depended on epigenetically regulated MED18.

LncRNA RHPN1-AS1 promoted cell proliferation, invasion and migration in cervical cancer via the modulation of miR-299-3p/FGF2 axis

AIMS

This study aims to determine the biological function and underlying mechanisms of lncRNA RHPN1 antisense RNA1 (RHPN1-AS1) in cervical cancer cell proliferation, invasion and migration.

MAIN METHODS

Gene expression was analysed by quantitative real-time PCR; protein levels were determined by western blot assay; in vitro functional assays determined the cervical cancer cell progression; in vivo tumor growth of cervical cancer cell was determined in nude mice xenograft models.

KEY FINDINGS

The results showed that RHPN1-AS1 was up-regulated in cervical cancer tissues and cell lines. In vitro functional assays demonstrated that RHPN1-AS1 overexpression promoted SiHa cell proliferation, invasion and migration; while RHPN1-AS1 knockdown showed the opposite effects. In vivo study showed that RHPN1-AS1 knockdown suppressed tumor growth in the nude mice. Further investigation showed that miR-299-3p was targeted and inversely regulated by RHPN1-AS1. In addition, miR-299-3p targeted the 3' untranslated region of fibroblast growth factor 2 (FGF2) to suppress its expression. The rescue experiments showed that the enhanced effects of RHPN1-AS1 overexpression on cell proliferation, growth, invasion and migration in SiHa cells were significantly attenuated by miR-299-3p overexpression or FGF2 inhibition. On the other hand, knockdown of miR-299-3p and overexpression of FGF2 both significantly increased cell proliferation, growth, invasion and migration in SiHa cells transfected with RHPN1-AS1 siRNA.

SIGNIFICANCE

In conclusion, our results revealed that RHPN1-AS1 promoted cervical cancer progression via targeting miR-299-3p/FGF2 axis. Our data suggested that RHPN1-AS1/miR-299-3p/FGF2 axis may be a promising target for cervical cancer treatment.

The long noncoding RNA KCNQ1DN suppresses the survival of renal cell carcinoma cells through downregulating c-Myc

Background: Long noncoding RNAs (lncRNAs) have been demonstrated to play essential roles in renal cell carcinoma (RCC). However, the role of lncRNA KCNQ1DN in RCC remains unclear.

Methods: The expression of KCNQ1DN in RCC and the corresponding adjacent tissues was measured by qPCR. RNA fluorescence in situ hybridization (FISH) assay, methylation analysis, reporter gene assays and functional tests were performed to reveal the effects of KCNQ1DN on RCC.

Results: In the present study, we found that lncRNA KCNQ1DN was notably decreased in RCC tissues and cell lines. RNA FISH assay showed that KCNQ1DN mainly localized to the cytoplasm. Methylation analysis revealed that the proximal region of KCNQ1DN promoter was hypermethylated in RCC tissues relative to the adjacent normal ones. Functional studies clarified that KCNQ1DN repressed the RCC cell growth and cell cycle progression. Mechanistically, KCNQ1DN inhibited the expression of c-Myc, which might further upregulate cyclin D1 and suppress p27 at mRNA and protein levels in RCC cells. Reporter gene assays revealed that the transcriptional activity of c-Myc promoter was inhibited by KCNQ1DN. The in vivo experiments in nude mice showed that KCNQ1DN overexpression dramatically repressed the growth of xenograft tumors and the expression of corresponding c-Myc.

Conclusion: These results indicated that KCNQ1DN inhibit the growth of RCC cells in vitro and in vivo through repressing the oncogene c-myc, suggesting that KCNQ1DN may serve as a novel target for the treatment of RCC.

Serous IFNA3 predicts unfavorable prognosis in lung cancer via abnormal activation of AKT signaling

This study addresses the demand through datamining The Cancer Genome Atlas (TCGA) database and elucidates mechanistic involvements of interferon alpha 8 (IFNA8) in lung cancer. The overall survival and disease-free survival of lung cancer patients in respect to IFNA8 expression level were analyzed. IFNA8 expression levels in both serum and tumor tissue were determined by real-time polymerase chain reaction. The diagnostic value of serous IFNA8 in lung cancer was assessed by receiver operating characteristic (ROC) curve analysis. Cell viability and proliferation were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Cell Counting Kit-8 assays. in vivo pro-tumor effect of IFNA8 was evaluated using xenograft tumor model. The metastasis-prone behaviors were determined by Transwell chamber assay and tail vein-injection in mice. Protein levels of p-AKT, total AKT, and endogenous reference actin were analyzed by western blot. We uncovered high IFNA8 associated with unfavorable overall survival and disease-free survival in lung cancer patients from TCGA. We further characterized the aberrant over-expression of IFNA8 in both peripheral blood and solid tumor from our clinical patient panel, and ROC analysis suggested its potential diagnostic value. Ectopic over-expression of IFNA8 promoted viability and proliferation in both A549 and H1299 cells in vitro and accelerated xenograft tumor growth in vivo. Furthermore, IFNA8 facilitated migration, invasion, and metastasis of A549 cells in vivo. Mechanistically, we disclosed the over-activation of AKT signaling in IFNA8-proficient A549 cells, inhibition of which completely abolished the pro-tumor effects of IFNA8. We have identified IFNA8 as a novel biomarker for either diagnostic or prognostic purpose in lung cancer, which is mechanistically associated with abnormal activation of AKT signaling.

Knockdown of LncRNA RHPN1-AS1 Inhibits Cell Migration, Invasion and Proliferation in Head and Neck Squamous Cell Carcinoma

Previous studies have revealed that long non-coding RNAs (lncRNAs) are involved in head and neck squamous cell carcinoma (HNSCC) progression. However, the detailed roles of lncRNA RHPN1-AS1 remain to be elucidated. In this study, by analyzing online RNA-Seq data, we found that RHPN1-AS1 was upregulated in HNSCC tissues and that its expression level was associated with neoplasm histologic grade. High expression of RHPN1-AS1 was also confirmed in HNSCC tissues. Knockdown of RHPN1-AS1 inhibited tumor cell migration, invasion and proliferation in HNSCC. Furthermore, inhibition of RHPN1-AS1 suppressed the expression of epithelial-mesenchymal transition (EMT)-related genes (β-Catenin, Claudin-1 and Vimentin) in HNSCC cells. Collectively, our results suggest that RHPN1-AS1, acting as an oncogene, may be a potential diagnostic and therapeutic target in HNSCC.

Silencing of the long non-coding RNA RHPN1-AS1 suppresses the epithelial-to-mesenchymal transition and inhibits breast cancer progression

Breast cancer (BC) is a frequently diagnosed malignancy in women. Increasing evidence implicates mis-expression of the long non-coding RNA (lncRNA) RHPN1 antisense RNA 1 (RHPN1-AS1) in the development of multiple cancer types. However, little is known about the expression pattern and function of lncRNA RHPN1-AS1 in the pathobiology of BC. We evaluated the expression of RHPN1-AS1 in The Cancer Genome Atlas dataset, and analyzed associations between RHPN1-AS1 expression and clinicopathologic features of BC patients. Additionally, we compared the expression of RHPN1-AS1 between BC and breast non-tumor samples via quantitative real-time polymerase chain reaction, and in situ hybridization, and evaluated the prognostic value of RHPN1-AS1 in a BC tissue microarray. We examined the impact of RHPN1-AS1 knockdown on proliferation, migration, and invasion of BC cells in vitro, and tumor growth in vivo. Bioinformatics analyses were used to predict the function of RHPN1-AS1 in BC. RHPN1-AS1 expression was upregulated in BC and elevated RHPN1-AS1 expression was strongly associated with poor prognosis of BC patients. Moreover, both univariate and multivariate analyses revealed that RHPN1-AS1 was a significant and independent predictor of BC prognosis. Functionally, RHPN1-AS1 silencing attenuated BC cell proliferation, migration, and invasion in vitro, and reduced tumor growth in xenograft models. Furthermore, RHPN1-AS1 silencing was associated with a decrease in the expression of epithelial-to-mesenchymal transition (EMT) markers in the xenograft tumors, suggesting that RHPN1-AS1 promotes invasion in BC cells by enhancing EMT. These findings suggest that RHPN1-AS1 is a potential prognostic biomarker and therapeutic target for BC.

c-Myc induced the regulation of long non-coding RNA RHPN1-AS1 on breast cancer cell proliferation via inhibiting P53

The global burden of breast cancer has been increasing, the mechanism of which is related to multifactorial accumulation of gene mutations. Dysregulation of long noncoding RNA (LncRNA) has been linked to multiple kinds of tumorigenesis. We aimed to identify functionally relevant targets of RHPN1 Antisense RNA 1 (RHPN1-AS1) in breast cancer using breast cancer cell line-based model. Quantitative RT-PCR revealed higher expression levels of RHPN1-AS1 in human breast cancer tissues and cell line MCF-7. RHPN1-AS1 was also located in MCF-7 cells by fluorescence in situ hybridization and western blot assays. Knockdown of RHPN1-AS1 delivered by lentivirus system inhibited MCF-7 cell proliferation indicated by the cell proliferation and colony formation assays, and the knockdown of RHPN1-AS1 enhanced P53 protein expression in MCF-7 and MDA-MB-231 cells. In addition, luciferase reporter assay validated that RHPN1-AS1 is a molecular sponge of miR-4261, and direct transcriptional target of c-Myc. RHPN1-AS1 exerts tumorigenesis by regulating P53 expression via MDM2 gene. These findings provide insights into the role and mechanism of action of lncRNA RHPN-AS1 in breast cancer.

Long non-coding RNAs in ocular diseases: new and potential therapeutic targets

Long non-coding RNAs (lncRNAs) are non-protein coding transcripts containing more than 200 nucleotides. In the past, lncRNAs were considered as 'transcript noise' or 'pseudogenes' and were thus ignored. However, in recent years, lncRNAs have been proven to regulate gene expression at the epigenetic, transcriptional and translational level, and thereby influence cell proliferation, apoptosis, viability, immune response and oxidative stress. Furthermore, increasing evidence points to their involvement in different diseases, including cancer and heart diseases. Recently, lncRNAs were shown to be differentially expressed in ocular tissues and play a significant role in the pathogenesis of ophthalmological disorders such as glaucoma, corneal diseases, cataract, diabetic retinopathy, proliferative vitreoretinopathy and ocular tumors. In this review, we summarize the classification and mechanisms of known lncRNAs, while detailing their biological functions and roles in ocular diseases. Moreover, we provide a concise review of the clinical relevance of lncRNAs as novel, potential therapeutic targets in the treatment of eye diseases.

Screening of important lncRNAs associated with the prognosis of lung adenocarcinoma, based on integrated bioinformatics analysis

The study aimed to elucidate the mechanisms underlying the occurrence and development of lung adenocarcinoma, and to reveal long non-coding RNA (lncRNA) prognostic factors to identify patients at high risk of disease recurrence or metastasis. Based on extensive RNA sequencing data and clinical survival prognosis information from patients with lung adenocarcinoma, obtained from The Cancer Genome Atlas and the Gene Expression Omnibus databases, a co-expression network of lncRNAs with different expression levels was built using weighted correlation network analysis and MetaDE.ES. The prognostic lncRNAs were identified using the Cox proportional hazards model and Kaplan-Meier survival curves to construct a risk scoring system. The reliability of the system was confirmed in validation datasets. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed on the genes significantly associated with the prognostic lncRNAs using gene set enrichment analysis. A total of 58 and 1,633 differentially expressed lncRNAs and mRNAs were identified, respectively. Considering the module stability, annotation, correlation between modules and clinical factors, and the differential expression levels of lncRNAs, 32 differentially expressed lncRNAs were selected from the brown, red, blue, green and yellow modules for subsequent survival analysis. A signature-based risk scoring system involving five lncRNAs [DIAPH2 antisense RNA 1, FOXN3 antisense RNA 2, long intergenic non-protein coding RNA 652, maternally expressed 3 and RHPN1 antisense RNA 1 (head to head)] was developed. The system successfully distinguished between low- and high-risk prognostic samples. System effectiveness was further verified using two independent validation datasets. Further KEGG pathway analysis indicated that the target genes of the five prognostic lncRNAs were associated with a number of cellular processes and signaling pathways, including the cell receptor-mediated signaling and cell adhesion pathways. A five-lncRNA signature predicts the prognosis of patients with lung adenocarcinoma. These prognostic lncRNAs may be potential diagnostic markers. The present results may help elucidate the pathogenesis of lung adenocarcinoma.

The lncRNA RHPN1-AS1 downregulation promotes gefitinib resistance by targeting miR-299-3p/TNFSF12 pathway in NSCLC

Although epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) gefitinib has exhibited notable clinical efficacy in non-small cell lung cancer (NSCLC) patients. However, its therapeutic efficacy is ultimately limited by the development of gefitinib resistance. The present study aimed to investigate the effects of the long non-coding RNA, RHPN1-AS1 on gefitinib resistance in NSCLC and explore the underlying mechanisms. In this study, RHPN1-AS1 was observed to be downregulated in gefitinib resistant patients and NSCLC cell lines. Besides, decreased expression of RHPN1-AS1 was found to be associated with poor prognosis of NSCLC patients. RHPN1-AS1 knockdown conferred gefitinib resistance to gefitinib sensitive NSCLC cells, whereas the overexpression of RHPN1-AS1 sensitized gefitinib resistant NSCLC cells to gefitinib treatment. Mechanistically, RHPN1-AS1 was found to positively regulate the expression of TNFSF12 by directly interacting with miR-299-3p. Collectively, RHPN1-AS1 modulates gefitinib resistance through miR-299-3p/TNFSF12 pathway in NSCLC. Our findings indicate that RHPN1-AS1 may serve as not only a prognostic biomarker for gefitinib resistance but also as a promising therapeutic biomarker and target for the treatment of NSCLC patients.

LncRNA SNHG16 drives proliferation, migration, and invasion of hemangioma endothelial cell through modulation of miR-520d-3p/STAT3 axis

It has been verified that long noncoding RNAs (lncRNAs) have great effects on various biological behaviors of human diseases. Although more and more lncRNAs have been studied in human cancers, countless lncRNAs still need to be excavated. This study aims to investigate the impacts of lncRNA SNHG16 on proliferation and metastasis of human hemangioma endothelial cell (HemECs). qRT-PCR analysis was carried out to explore the expression pattern of SNHG16, miR-520d-3p, and STAT3. The effect of SNHG16 on cell proliferation was detected by MTT and colony formation assay. Flow cytometry analysis was performed to test the apoptosis of HemECs cells. Migration and invasion of HemECs cells were determined and examined by transwell assays. Tube formation assay helped to observe the influence of SNHG16 expression on the vasoformation of HemECs cells. The correlations among SNHG16, miR-520d-3p, and STAT3 were certified by bioinformatics analysis, pull-down assay, and dual-luciferase reporter assay. Finally, rescue assays were conducted to demonstrate the effects of SNHG16-miR-520d-3p-STAT3 axis on biological behaviors of HemECs cell. SNHG16 was strongly expressed in proliferating phase hemangioma tissues and HemECs cells. Silenced SNHG16 negatively affected proliferation, migration, and invasion of HemECs cell. LncRNA SNHG16 acted as a ceRNA to upregulate STAT3 through binding with miR-520d-3p in HemECs cell. LncRNA SNHG16 acted as a ceRNA to drive proliferation, vasoformation, migration, and invasion of HemECs cells through modulating miR-520d-3p/STAT3 axis.