Long non-coding RNA NORAD upregulate SIP1 expression to promote cell proliferation and invasion in cervical cancer

MicroRNAs, long non-coding RNAs, and circular RNAs and gynecological cancers: focus on metastasis

Gynecologic cancer is a significant cause of death in women worldwide, with cervical cancer, ovarian cancer, and endometrial cancer being among the most well-known types. The initiation and progression of gynecologic cancers involve a variety of biological functions, including angiogenesis and metastasis-given that death mostly occurs from metastatic tumors that have invaded the surrounding tissues. Therefore, understanding the molecular pathways underlying gynecologic cancer metastasis is critical for enhancing patient survival and outcomes. Recent research has revealed the contribution of numerous non-coding RNAs (ncRNAs) to metastasis and invasion of gynecologic cancer by affecting specific cellular pathways. This review focuses on three types of gynecologic cancer (ovarian, endometrial, and cervical) and three kinds of ncRNAs (long non-coding RNAs, microRNAs, and circular RNAs). We summarize the detailed role of non-coding RNAs in the different pathways and molecular interactions involved in the invasion and metastasis of these cancers.

lncRNA NORAD, soluble ICAM1 and their correlations may be related to the regulation of the tumor immune microenvironment in laryngeal squamous cell carcinoma (LSCC)

NORAD, non-coding RNA activated by DNA damage, is a Long non-coding RNA (lncRNA) transcript that modulates genome stability and has been reported to be dysregulated in different cancers. Although it has been reported to be upregulated in tumor cells mostly for solid organ cancers, it has also been reported to be downregulated in some cancers. Although the pathophysiological mechanism is not fully understood, a negative correlation between NORAD and intercellular cell adhesion molecule-1 (ICAM-1) has been shown in experimental models, but this situation has not been evaluated in terms of cancer. We aimed to evaluate the potential roles of these two biomarker candidates together and separately in the clinicopathological axis in Laryngeal squamous cell carcinoma (LSCC) in a case-control study setting. The interactions of NORAD and ICAM1 at the RNA level were evaluated interactively by the RIblast program. sICAM1 (soluble intercellular cell adhesion molecule-1) levels were determined by ELISA in one hundred and five individuals (forty-four LSCC, sixty-one control) and lncRNA NORAD expression in eighty-eight tissues (forty-four LSCC tumors, forty-four tumor-free surrounding tissues) was determined by Real-time PCR. While the energy treesholud was - 16 kcal/mol between NORAD and ICAM1, the total energy was 176.33 kcal/mol, and 9 base pair pairings from 4 critical points were detected. NORAD expression level was found to be higher in tumor surrounding tissue compared to tumor tissue, and sICAM1 was higher in the control group compared to LSCC (p = 0.004; p = 0.02). NORAD discreminte tumor surrounding tissue from tumor (AUC: 0.674; optimal sensitivity:87.50%; optimal specificity 54.55%; cut-off point as >1.58 fold change; P = 0.034). The sICAM1 level was found to be higher in the control (494,814 ± 93.64 ng/L) than LSCC (432.95 ± 93.64 ng/L) (p = 0.02). sICAM1 discreminte control group from LSCC (AUC: 0.624; optimal sensitivity 68,85%; optimal specificity 61,36%; cut-off point ≤115,0 ng/L; (p = 0.033). A very strong negative correlation was found between NORAD expression and patients' sICAM1 levels (r = -.967; n = 44; p = 0.033). sICAM1 levels were found to be 1.63 times higher in NORAD downregulated subjects compared to upregulated ones (p = 0.031). NORAD was 3.63 times higher in those with alcohol use, and sICAM 1 was 5.77 times higher in those without distant organ metastasis (p = 0.043; 0.004). The increased NORAD expression in the tumor microenvironment in LSCC, the activation of T cells via TCR signaling, and the decrease of sICAM in the control group in correlation with NORAD suggests that ICAM1 may be needed as a membrane protein in the tumor microenvironment. NORAD and ICAM1 may be functionally related to tumor microenvironment and immune control in LSCC.

LncRNA weighted gene co-expression network analysis reveals novel biomarkers related to prostate cancer metastasis

BACKGROUND

Most prostate cancer patients die from metastasis and lack accurate efficacious biomarkers to monitor the disease behavior, optimize treatment and assess prognosis. Herein, we aimed to identify meaningful lncRNA biomarkers associated with prostate cancer metastatic progression.

METHODS

By repurposing microarray probes, 11,624 lncRNAs in prostate cancer were obtained from Gene Expression Omnibus  database (GSE46691, N = 545; GSE29079, N = 235; GSE94767, N = 130). Weighted gene co-expression network analysis was applied to determine the co-expression lncRNA network pertinent to metastasis. Hub lncRNAs were screened. RNA-seq and clinical data from the Cancer Genome Atlas prostate cancer (TCGA-PRAD) cohort (N = 531) were analyzed. Transwell assay and bioinformatic analysis were performed for mechanism research.

RESULTS

The high expression levels of nine hub lncRNAs (FTX, AC005261.1, NORAD, LINC01578, AC004542.2, ZFAS1, EBLN3P, THUMPD3-AS1, GAS5) were significantly associated with Gleason score and increased probability of metastatic progression. Among these lncRNAs, ZFAS1 had the consistent trends of expression in all of the analysis from different cohorts, and the Kaplan-Meier survival analyses showed higher expression of ZFAS1 was associated with shorter relapse free survival. In-vitro studies confirmed that downregulation of ZFAS1 decreased prostate cancer cell migration.

CONCLUSION

We offered some new insights into discovering lncRNA markers correlated with metastatic progression of prostate cancer using the WGCNA. Some may serve as potential prognostic biomarkers and therapeutic targets for advanced metastatic prostate cancer.

The clinical prognostic value of lncRNA FOXP4-AS1 in cancer patients: A meta-analysis and bioinformatics analysis based on TCGA datasets

BACKGROUND

The mortality and recurrence of patients with cancer is of high prevalence. Long non-coding RNA (lncRNA) forkhead box P4 antisense RNA 1 (FOXP4-AS1) is a promising lncRNA. There is increasing evidence that lncRNA FOXP4-AS1 is abnormally expressed in various tumors and is associated with cancer prognosis. This study was designed to identify the prognostic value of lncRNA FOXP4-AS1 in human malignancies.

METHODS

We searched electronic databases up to April 29, 2022, including PubMed, Cochrane Library, Embase, MEDLINE, and Web of Science. Eligible studies that evaluated the clinicopathological and prognostic role of lncRNA FOXP4-AS1 in patients with malignant tumors were included. The pooled odds ratios (ORs) and the hazard ratios (HRs) were calculated to assess the role of lncRNA FOXP4-AS1 using Stata/SE 16.1 software.

RESULTS

A total of 6 studies on cancer patients were included in the present meta-analysis. The combined results revealed that high expression of lncRNA FOXP4-AS1 was significantly associated with unfavorable overall survival (OS) (HR = 1.99, 95% confidence interval [CI]: 1.65-2.39, P < .00001), and poor disease-free survival (DFS) (HR = 1.81, 95% CI: 1.54-2.13, P < .00001) in a variety of cancers. In additional, the increase in lncRNA FOXP4-AS1 expression was also correlated with tumor size ((larger vs smaller) (OR = 3.16, 95% CI: 2.12-4.71, P < .00001), alpha-fetoprotein (≥400 vs <400) (OR = 3.81, 95%CI: 2.38-6.11, P = .83), lymph node metastasis (positive vs negative) (OR = 2.93, 95%CI: 1.51-5.68, P = .001), and age (younger vs older) (OR = 2.06, 95% CI: 1.41-3.00, P = .00002) in patients with cancer. Furthermore, analysis results using The Cancer Genome Atlas (TCGA) dataset showed that the expression level of lncRNA FOXP4-AS1 was higher in most tumor tissues than in the corresponding normal tissues, which predicted a worse prognosis.

CONCLUSIONS

In this meta-analysis, we demonstrate that high lncRNA FOXP4-AS1 expression may become a potential marker to predict cancer prognosis.

Emerging Roles and Potential Applications of Non-Coding RNAs in Cervical Cancer

Cervical cancer (CC) is a preventable disease using proven interventions, specifically prophylactic vaccination, pervasive disease screening, and treatment, but it is still the most frequently diagnosed cancer in women worldwide. Patients with advanced or metastatic CC have a very dismal prognosis and current therapeutic options are very limited. Therefore, understanding the mechanism of metastasis and discovering new therapeutic targets are crucial. New sequencing tools have given a full visualization of the human transcriptome's composition. Non-coding RNAs (NcRNAs) perform various functions in transcriptional, translational, and post-translational processes through their interactions with proteins, RNA, and even DNA. It has been suggested that ncRNAs act as key regulators of a variety of biological processes, with their expression being tightly controlled under physiological settings. In recent years, and notably in the past decade, significant effort has been made to examine the role of ncRNAs in a variety of human diseases, including cancer. Therefore, shedding light on the functions of ncRNA will aid in our better understanding of CC. In this review, we summarize the emerging roles of ncRNAs in progression, metastasis, therapeutics, chemo-resistance, human papillomavirus (HPV) regulation, metabolic reprogramming, diagnosis, and as a prognostic biomarker of CC. We also discussed the role of ncRNA in the tumor microenvironment and tumor immunology, including cancer stem cells (CSCs) in CC. We also address contemporary technologies such as antisense oligonucleotides, CRISPR-Cas9, and exosomes, as well as their potential applications in targeting ncRNAs to manage CC.

LncRNA HCG11 represses ovarian cancer cell growth via AKT signaling pathway

AIM

Ovarian cancer is a main contributor of cancer-relevant deaths among women worldwide due to high incidence and mortality. Mounting evidence has unveiled that lncRNAs play critical roles in malignancies, including ovarian cancer. Although the tumor suppressor function of HCG11 in prostate cancer and glioma has been proved, investigations on HCG11 role in ovarian cancer are still scarce.

METHODS

Gene or protein expression was quantified by RT-qPCR or western blot. HCG11 effects on ovarian cancer were assessed by functional assays. Bioinformatics analysis and mechanism experiments were implemented to identify the association among HCG11, miR-1270, and PTEN.

RESULTS

HCG11 was weakly expressed in ovarian cancer and functioned as a tumor suppressor in ovarian cancer by retarding cell proliferation, migration, and EMT. Besides, HCG11 could bind to miR-1270 and PTEN was a target gene of miR-1270. Mechanically, HCG11 competitively bound with miR-1270 to upregulate PTEN. From rescue experiments, HCG11 impeded AKT/mTOR pathway to retard ovarian cancer cell growth by miR-1270/PTEN.

CONCLUSIONS

HCG11 was a tumor suppressor in ovarian cancer cells and additionally, HCG11 regulated AKT/mTOR pathway to hinder ovarian cancer cell growth via modulating miR-1270/PTEN, indicating that HCG11 may represent a promising target for effective treatment of ovarian cancer patients.

LncRNA NORAD facilitates oral squamous cell carcinoma progression by sponging miR-577 to enhance TPM4

BACKGROUND

Long non-coding RNAs (lncRNAs) have been reported to be vital factors to affect the expression of genes and proteins. Also, it has been proved that the abnormal expression or mutation of lncRNAs stands as a signal of metastasis and proliferation of cancer. Nevertheless, the majority of lncRNAs still need to be explored in abundant cancers especially in oral squamous cell carcinoma (OSCC).

METHODS

RT-qPCR assays were applied to test the expression of RNAs. Mechanism assays were performed to verify the combination among NORAD, TPM4 and miR-577. Also, functional assays were conducted to verify the function of RNAs on OSCC cells.

RESULTS

LncRNA NORAD was highly expressed in OSCC tissues and cells. NORAD silencing repressed the biological behaviors of OSCC cells. MiR-577 was found in OSCC with low expression, and RIP assays illustrated that NORAD, miR-577 and TPM4 coexisted in RNA-induced silencing complexes. Rescue assays proved that the overexpression of TPM4 could recover the effect of NORAD silencing on OSCC progression.

CONCLUSIONS

It was revealed that NORAD functioned as a tumor promoter to sponge miR-577 thus elevating TPM4 in OSCC, which indicated that NORAD was worthy to be studied as a target for the treatment of OSCC.

Comprehensive analysis of lymph nodes metastasis associated genes in cervical cancer and its significance in treatment and prognosis

Background

Cervical carcinoma is one of the most common malignant tumors of the female reproductive system. Lymph nodes metastasis, the most common metastasis, which can be detected even in small-size tumor patients, results in worse prognosis. Therefore, it is of great significance to explore novel lymph nodes metastasis associated biomarkers, which can predict the prognosis and provide a good reference for clinical decision making in cervical carcinoma patients. However, systematic and comprehensive studies related to the key molecules in lymph node metastasis in cervical carcinoma patients are still absent.

Methods

Transcriptome and clinical data of 307 cervical carcinoma patients were obtained from The Cancer Genome Atlas (TCGA). Then, survival of patients with and without lymph node metastasis was analyzed by Kaplan-Meier (K-M) curves. Differential expressed genes (DEGs) were detected between tumor and control samples using limma package and defined as lymph node metastasis related genes. Univariate and multivariate Cox regression analyses were carried out to screen robust prognostic gene signature. The risk score model and nomogram for predicting survival were constructed based on prognostic gene signature. The performance of the risk score model was evaluated by operating characteristic (ROC) curves. Based on risk score, patients were divided into low- and high- risk groups. DEGs, functional enrichment analysis and tumor microenvironment (immune infiltration and expressions of immune checkpoints) were detected in low- and high-risk groups.

Results

A total of 103 lymph node metastasis-associated genes were identified. Univariate and multivariate Cox regression analyses identified TEKT2, LPIN2, FABP4 and CXCL2 as prognostic gene signature. The risk score model was constructed and validated in cervical carcinoma patients. 345 DEGs identified between high- and low-risk groups were significantly enriched into immune-related biological processes. Furthermore, we found that the immune infiltration and expressions of immune checkpoints were significantly different between low- and high-risk groups.

Conclusion

Our study revealed that lymph node metastasis played an important role in the prognosis of cervical carcinoma patients. Furthermore, we established a risk score model based on lymph node metastasis related genes, which could accurately predict the survival of cervical carcinoma patients. Besides, our findings in tumor microenvironments of low- and high-risk groups improved our understanding of the relationship between lymph node metastasis related genes and cervical carcinoma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08945-8.

RHO GTPase-Related Long Noncoding RNAs in Human Cancers

RHO GTPases are critical signal transducers that regulate cell adhesion, polarity, and migration through multiple signaling pathways. While all these cellular processes are crucial for the maintenance of normal cell homeostasis, disturbances in RHO GTPase-associated signaling pathways contribute to different human diseases, including many malignancies. Several members of the RHO GTPase family are frequently upregulated in human tumors. Abnormal gene regulation confirms the pivotal role of lncRNAs as critical gene regulators, and thus, they could potentially act as oncogenes or tumor suppressors. lncRNAs most likely act as sponges for miRNAs, which are known to be dysregulated in various cancers. In this regard, the significant role of miRNAs targeting RHO GTPases supports the view that the aberrant expression of lncRNAs may reciprocally change the intensity of RHO GTPase-associated signaling pathways. In this review article, we summarize recent advances in lncRNA research, with a specific focus on their sponge effects on RHO GTPase-targeting miRNAs to crucially mediate gene expression in different cancer cell types and tissues. We will focus in particular on five members of the RHO GTPase family, including RHOA, RHOB, RHOC, RAC1, and CDC42, to illustrate the role of lncRNAs in cancer progression. A deeper understanding of the widespread dysregulation of lncRNAs is of fundamental importance for confirmation of their contribution to RHO GTPase-dependent carcinogenesis.

Long non-coding RNA NORAD promotes pancreatic cancer stem cell proliferation and self-renewal by blocking microRNA-202-5p-mediated ANP32E inhibition

Background

Cancer stem cells (CSCs) are key regulators in the processes of tumor initiation, progression, and recurrence. The mechanism that maintains their stemness remains enigmatic, although the role of several long noncoding RNAs (lncRNAs) has been highlighted in the pancreatic cancer stem cells (PCSCs). In this study, we first established that PCSCs overexpressing lncRNA NORAD, and then investigated the effects of NORAD on the maintenance of PCSC stemness.

Methods

Expression of lncRNA NORAD, miR-202-5p and ANP32E in PC tissues and cell lines was quantified after RNA isolation. Dual-luciferase reporter assay, RNA pull-down and RIP assays were performed to verify the interactions among NORAD, miR-202-5p and ANP32E. We then carried out gain- and loss-of function of miR-202-5p, ANP32E and NORAD in PANC-1 cell line, followed by measurement of the aldehyde dehydrogenase activity, cell viability, apoptosis, cell cycle distribution, colony formation, self-renewal ability and tumorigenicity of PC cells.

Results

LncRNA NORAD and ANP32E were upregulated in PC tissues and cells, whereas the miR-202-5p level was down-regulated. LncRNA NORAD competitively bound to miR-202-5p, and promoted the expression of the miR-202-5p target gene ANP32E thereby promoting PC cell viability, proliferation, and self-renewal ability in vitro, as well as facilitating tumorigenesis of PCSCs in vivo.

Conclusion

Overall, lncRNA NORAD upregulates ANP32E expression by competitively binding to miR-202-5, which accelerates the proliferation and self-renewal of PCSCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03052-5.

Non-coding RNA Activated by DNA Damage: Review of Its Roles in the Carcinogenesis

Long intergenic non-coding RNA 00657 (LINC00657) or "non-coding RNA activated by DNA damage" (NORAD) is an extremely conserved and copious long non-coding RNA (lncRNA). This transcript has pivotal role in the preservation of genome integrity. Several researches have appraised the role of NORAD in the evolution of human cancers with most of them indicating an oncogenic role for this lncRNA. Several miRNAs such as miR-199a-3p, miR-608, miR-155-5p, miR-590-3p, miR-495-3p, miR-608, miR-202-5p, miR-125a-3p, miR-144-3p, miR-202-5p, and miR-30a-5p have been recognized as targets of NORAD in different cancer cell lines. In addition, NORAD has interactions with cancer-related pathways, particularly STAT, TGF-β, Akt/mTOR, and PI3K/AKT pathway. Over-expression of NORAD has been related with poor clinical outcome of patients with diverse types of neoplasms. Collectively, NORAD is a prospective marker and target for combating cancer.

Silencing the lncRNA NORAD inhibits EMT of head and neck squamous cell carcinoma stem cells via miR‑26a‑5p

Cancer stem cells are closely associated with tumor metastasis or recurrence. According to previous literature reports, microRNA (miR)‑26a has an inhibitory effect on head and neck squamous cell carcinoma (HNSCC), and the long non‑coding RNA (lncRNA) non‑coding RNA activated by DNA damage (NORAD) has been found to interact with miR‑26a‑5p. The present study aimed to investigate the regulation and mechanism of NORAD and miR‑26a‑5p in the epithelial‑mesenchymal transition (EMT) of HNSCC stem cells. An ALDEFLUOR stem cell detection kit, a flow cytometer, a self‑renewal ability test and western blotting were used to sort and identify HNSCC stem cells. The ENCORI website and a dual‑luciferase assay were used to assess the relationship between genes. The mRNA and protein expression levels of NORAD, miR‑26a‑5p and EMT‑related genes were detected via reverse transcription‑quantitative PCR and western blotting. Functional experiments (MTT assay, flow cytometry, wound healing assay and Transwell assay) were conducted to analyze the effects of NORAD and miR‑26a‑5p on HNSCC stem cells. The successfully sorted aldehyde dehydrogenase (ALDH)⁺ cells had a self‑renewal capacity and displayed upregulated expression levels of CD44, Oct‑4 and Nanog. NORAD knockdown, achieved using small interfering (si)RNA, downregulated the expression levels of tumor markers in ALDH⁺ cells. siNORAD inhibited cell vitality, migration and invasion, as well as promoted apoptosis, increased the expression of epithelial cell markers and decreased the expression of interstitial cell markers in HNSCC stem cells. miR‑26a‑5p was a downstream gene of NORAD, and knockdown of miR‑26a‑5p partially offset the regulatory effect of siNORAD on HNSCC stem cells. Collectively, the present study demonstrated that NORAD knockdown attenuated the migration, invasion and EMT of HNSCC stem cells via miR‑26a‑5p.

MYBL2-induced PITPNA-AS1 upregulates SIK2 to exert oncogenic function in triple-negative breast cancer through miR-520d-5p and DDX54

Background

In recent years, long non-coding RNAs (lncRNAs) have attracted much attention because of its regulatory role in occurrence and progression of tumors, including triple-negative breast cancer (TNBC). LncRNA PITPNA antisense RNA 1 (PITPNA-AS1) has been explored in some cancers, whereas its function and molecular mechanism in TNBC remain unclear.

Methods

PITPNA-AS1 expression in TNBC tissues and cells was determined by RT-qPCR. TNBC cell viability, proliferation, migration, invasion were assessed with CCK-8, colony formation, wound healing, transwell assays. Cell apoptosis was evaluated by flow cytometry. Expression of EMT-related markers was detected by western blot analyses. The molecular mechanism of PITPNA-AS1 was explored by RNA pull down, luciferase reporter, RIP and ChIP assays.

Results

PITPNA-AS1 showed high expression levels in TNBC tissues and cells. PITPNA-AS1 knockdown suppressed TNBC cell viability, proliferation, migration, invasion in vitro and inhibited xenograft tumor growth in mice. Mechanistically, PITPNA-AS1 upregulated SIK2 expression by sponging miR-520d-5p and recruiting DDX54 protein. Results of rescue assays suggested that the inhibitive effects of silenced PITPNA-AS1 on TNBC cellular processes were partially rescued by overexpressing SIK2 or combination of miR-520d-5p inhibition and DDX54 overexpression. More importantly, we found that the upregulation of PITPNA-AS1 in TNBC cells was attributed to transcription factor MYBL2.

Conclusion

PITPNA-AS1 activated by MYBL2 plays an oncogenic role in TNBC through upregulating SIK2.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02956-6.

Competing Endogenous RNAs in Cervical Carcinogenesis: A New Layer of Complexity

MicroRNAs (miRNAs) regulate gene expression by binding to complementary sequences within target mRNAs. Apart from working ‘solo’, miRNAs may interact in important molecular networks such as competing endogenous RNA (ceRNA) axes. By competing for a limited pool of miRNAs, transcripts such as long noncoding RNAs (lncRNAs) and mRNAs can regulate each other, fine-tuning gene expression. Several ceRNA networks led by different lncRNAs—described here as lncRNA-mediated ceRNAs—seem to play essential roles in cervical cancer (CC). By conducting an extensive search, we summarized networks involved in CC, highlighting the major impacts of such dynamic molecular changes over multiple cellular processes. Through the sponging of distinct miRNAs, some lncRNAs as HOTAIR, MALAT1, NEAT1, OIP5-AS1, and XIST trigger crucial molecular changes, ultimately increasing cell proliferation, migration, invasion, and inhibiting apoptosis. Likewise, several lncRNAs seem to be a sponge for important tumor-suppressive miRNAs (as miR-140-5p, miR-143-3p, miR-148a-3p, and miR-206), impairing such molecules from exerting a negative post-transcriptional regulation over target mRNAs. Curiously, some of the involved mRNAs code for important proteins such as PTEN, ROCK1, and MAPK1, known to modulate cell growth, proliferation, apoptosis, and adhesion in CC. Overall, we highlight important lncRNA-mediated functional interactions occurring in cervical cells and their closely related impact on cervical carcinogenesis.

Cervical Cancer Stem-Like Cell Transcriptome Profiles Predict Response to Chemoradiotherapy

Cervical cancer (CC) represents a major global health issue, particularly impacting women from resource constrained regions worldwide. Treatment refractoriness to standard chemoradiotheraphy has identified cancer stem cells as critical coordinators behind the biological mechanisms of resistance, contributing to CC recurrence. In this work, we evaluated differential gene expression in cervical cancer stem-like cells (CCSC) as biomarkers related to intrinsic chemoradioresistance in CC. A total of 31 patients with locally advanced CC and referred to Mário Penna Institute (Belo Horizonte, Brazil) from August 2017 to May 2018 were recruited for the study. Fluorescence-activated cell sorting was used to enrich CD34+/CD45- CCSC from tumor biopsies. Transcriptome was performed using ultra-low input RNA sequencing and differentially expressed genes (DEGs) using Log2 fold differences and adjusted p-value < 0.05 were determined. The analysis returned 1050 DEGs when comparing the Non-Responder (NR) (n=10) and Responder (R) (n=21) groups to chemoradiotherapy. These included a wide-ranging pattern of underexpressed coding genes in the NR vs. R patients and a panel of lncRNAs and miRNAs with implications for CC tumorigenesis. A panel of biomarkers was selected using the rank-based AUC (Area Under the ROC Curve) and pAUC (partial AUC) measurements for diagnostic sensitivity and specificity. Genes overlapping between the 21 highest AUC and pAUC loci revealed seven genes with a strong capacity for identifying NR vs. R patients (ILF2, RBM22P2, ACO16722.1, AL360175.1 and AC092354.1), of which four also returned significant survival Hazard Ratios. This study identifies DEG signatures that provide potential biomarkers in CC prognosis and treatment outcome, as well as identifies potential alternative targets for cancer therapy.

The Clinical Prognostic Value of lncRNA SBF2-AS1 in Cancer Patients: A Meta-Analysis

Background:

The mortality and recurrence of patients with cancer is of high prevalence. SET-binding factor 2 (SBF2) antisense RNA1 (lncRNA-SBF2-AS1) is a promising long non-coding RNA. There is increasing evidence that SBF2-AS1 is abnormally expressed in various tumors and is associated with cancer prognosis. However, the identification of the effect of lncRNA SBF2-AS1 in tumors remains necessary.

Materials and Methods:

Up to November 2, 2020, electronic databases, including PubMed, Cochrane Library, EMBASE, Medline, and Web of Science, were searched. The results were evaluated by pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs).

Results:

A total of 11 literatures on cancer patients were included for the present meta-analysis. The combined results revealed that high expression of SBF2-AS1 was significantly associated with unfavorable overall survival (OS) (HR = 1.48, 95% CI: 1.34-1.62, P < 0.00001) in a variety of cancers. In additional, the increase in SBF2-AS1 expression was also correlated with tumor size ((larger vs. smaller) OR = 2.34, 95% CI: 1.47-3.70, P = 0.0003), advanced TNM stage ((III/IV vs. I/II) OR = 2.78, 95% CI: 1.75-4.41, P < 0.0001), lymph node metastasis ((Positive vs. Negative) OR = 3.06, 95% CI: 1.93-4.86, P < 0.00001), and histological grade ((poorly vs. well/moderately) OR = 2.58, 95% CI: 1.47-4.52, P = 0.001) in patients with cancer. Furthermore, The Cancer Genome Atlas (TCGA) dataset valuated that SBF2-AS1 was upregulated in a variety of tumors, and predicted the worse prognosis.

Conclusions:

Our results of this meta-analysis demonstrate that high SBF2-AS1 expression may become a potential target for predicting the prognosis of human cancers.

So alike yet so different. Differential expression of the long non-coding RNAs NORAD and HCG11 in breast cancer subtypes

Breast cancer (BC) is a heterogeneous disease, and it is the leading cause of death among women. NORAD and HCG11 are highly similar lncRNAs that present binding sites for PUMILIO proteins. PUMILIO acts on hundreds of mRNA targets, contributing to the modulation of gene expression. We analyzed the expression levels of NORAD and HCG11 in the BC subtypes luminal A (LA) and basal-like (BL), and the regulatory networks associated with these lncRNAs. In the analysis of TCGA cohort (n=329) and Brazilian BC samples (n=44), NORAD was up-regulated in LA while HCG11 was up-regulated in BL subtype. An increased expression of NORAD is associated with reduced disease-free survival in basal-like patients (p = 0.002), which suggests that its prognostic value could be different in specific subtypes. The biological pathways observed for the HCG11 network are linked to the epithelial-to-mesenchymal transition; while NORAD associated pathways appear to be related to luminal epithelial cell transformation. NORAD and HCG11 regulons respectively present 36% and 21.5% of PUMILIO targets, which suggests that these lncRNAs act as a decoy for PUMILIO. These lncRNAs seem to work as players in the differentiation process that drives breast cells to acquire distinct phenotypes related to a specific BC subtype.

Prognostic and clinicopathological role of long noncoding RNA NORAD in various cancers: a meta-analysis

Aim: Long noncoding RNA (lncRNA) noncoding RNA activated by DNA damage (NORAD) is widely investigated in different tumors. Our meta-analysis intends to assess the prognostic and clinicopathological value of NORAD in cancers. Materials & methods: We searched PubMed, Web of Science, Embase and Chinese National Knowledge Infrastructure from inception to 1 August 2020. Results: The results showed that higher expression of NORAD had a significant association with worse overall survival. Additionally, correlations were detected between elevated level of NORAD and poor differentiation degree, positive lymph node metastasis and large tumor size in cancer patients. Conclusion: LncRNA NORAD can serve as a novel and promising biomarker for prognosis and clinicopathological characteristics in different cancers.

Long non-coding RNA NORAD upregulation induced by airborne particulate matter (PM10) exposure leads to aneuploidy in A549 lung cells

Air pollution is a worldwide problem that affects human health predominantly in the largest cities. Particulate matter of 10 μm or less in diameter (PM₁₀) is considered a risk factor for multiple diseases, including lung cancer. The long non-coding RNA NORAD and the components of the spindle assembly checkpoint (SAC) ensure proper chromosomal segregation. Alterations in the SAC cause aneuploidy, a feature associated with carcinogenesis. In this study, we demonstrated that PM₁₀ treatment increased the expression levels of NORAD as well as those of SAC components mitotic arrest deficient 1 (MAD1L1), mitotic arrest deficient 2 (MAD2L1), BubR1 (BUB1B), aurora B (AURKB), and survivin (BIRC5) in the lung A549 cell line. We also demonstrated that MAD1L1, MAD2L1, and BUB1B expression levels were reduced when cells were transfected with small interfering RNAs (siRNAs) against NORAD. Interestingly, the expression levels of AURKB and BIRC5 (survivin) were not affected by transfection with NORAD siRNAs. Cells treated with PM₁₀ exhibited a decrease in mitotic arrest and an increase in micronuclei frequency in synchronized A549 cells. PM₁₀ exposure induced aneuploidy events as a result of SAC deregulation. We also observed a reduction in the protein levels of Pumilio 1 after PM₁₀ treatment. Our results provide novel clues regarding the effect of PM₁₀ in the generation of chromosomal instability, a phenotype observed in lung cancer cells.

LncRNA NORAD promotes bone marrow stem cell differentiation and proliferation by targeting miR-26a-5p in steroid-induced osteonecrosis of the femoral head

BACKGROUND

Steroid-induced osteonecrosis of the femoral head (SONFH) is a devastating orthopedic disease, which seriously affects the quality of life of patients. The study aims to investigate the effects of LncRNA NORAD on SONFH.

METHODS

Human bone marrow-derived mesenchymal stem cells (hBMSCs) were isolated from the proximal femur of patients during routine orthopedic surgery and then cultured with dexamethasone (Dex) and transfected with NORAD overexpression vector, siRNA-NORAD and miR-26a-5p mimics. The mRNA expression of NORAD, miR-26a-5p, OPG, RANK, and RANKL was detected by RT-qPCR. Cell proliferation and apoptosis was measured by CCK-8 assay and flow cytometry, respectively. The protein expression of RUNX2, OPG, RANK, and RANKL was detected by western blot. The dual-luciferase reporter gene assay was performed to confirm the binding between NORAD and miR-26a-5p.

RESULTS

NORAD expression was downregulated in SONFH tissues, while miR-26a-5p expression was upregulated. Overexpression of NORAD improved DEX-induced inhibition of proliferation and differentiation, and promotion of apoptosis in hBMSCs, while knockdown of NORAD led to the opposite results. Moreover, NORAD improved DEX-induced inhibition of proliferation and differentiation, and promotion of apoptosis by regulation of miR-26a-5p in hBMSCs.

CONCLUSIONS

NORAD expression was downregulated in SONFH tissues, while miR-26a-5p expression was upregulated. NORAD improved DEX-induced inhibition of proliferation and differentiation, and promotion of apoptosis by regulation of miR-26a-5p in hBMSCs.

Gynecologic cancers and non-coding RNAs: Epigenetic regulators with emerging roles

Gynecologic cancers involve the female genital organs, such as the vulva, vagina, cervix, endometrium, ovaries, and fallopian tubes. The occurrence and frequency of gynecologic cancer depends on personal lifestyle, history of exposure to viruses or carcinogens, genetics, body shape, and geographical habitat. For a long time, research into the molecular biology of cancer was broadly restricted to protein-coding genes. Recently it has been realized that non-coding RNAs (ncRNA), including long noncoding RNAs (LncRNAs), microRNAs, circular RNAs and piRNAs (PIWI-interacting RNAs), can all play a role in the regulation of cellular function within gynecological cancer. It is now known that ncRNAs are able to play dual roles, i.e. can exert both oncogenic or tumor suppressive functions in gynecological cancer. Moreover, several clinical trials are underway looking at the biomarker and therapeutic roles of ncRNAs. These efforts may provide a new horizon for the diagnosis and treatment of gynecological cancer. Herein, we summarize some of the ncRNAs that have been shown to be important in gynecological cancers.

LMCD1 antisense RNA 1 (LMCD1-AS1) potentiates thyroid cancer cell growth and stemness via a positive feedback loop of LMCD1-AS1/miR-1287-5p/GLI2

Background

LMCD1 antisense RNA 1 (LMCD1-AS1) is a certified oncogene in several tumour types. However, its role in thyroid cancer (THCA) remains unknown.

Methods

The expression level of LMCD1-AS1 in THCA cells and the normal control cell was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The effects of LMCD1-AS1 knockdown on cell proliferation, migration and apoptosis were detected by colony formation assay, EdU assay, wound healing assay and TUNEL assay. Sphere formation assay was applied to assess sphere formation ability of THCA cells. Bioinformatics analysis and mechanism experiments, including ChIP assay, RIP assay and luciferase reporter assay were conducted to evaluate the downstream and upstream molecular mechanisms of LMCD-AS1.

Results

A marked up-regulation of LMCD1-AS1 in THCA cells relative to normal control cells was found. LMCD1-AS1 silencing suppressed proliferation and migration but induced apoptosis in THCA cells. Moreover, LMCD1-AS1 knockdown reduced the sphere formation capacity of THCA cells. The transcriptional factor GLI family zinc finger 2 (GLI2) binds to LMCD1-AS1, which contributed to LMCD1-AS1 up-regulation in THCA cells. Cytoplasmic LMCD1-AS1 sponged a shared microRNA between LMCD1-AS1 and GLI2. GLI2 was inhibited bymiR-1287-5p and disinhibited by LMCD1-AS1.

Conclusions

LMCD1-AS1exerts pro-tumorigenic function through sponging miR-1287-5p to elevate GLI2 expression in THCA development, constituting a feedback loop of LMCD1-AS1/miR-1287-5p/GLI2.

NORAD, a critical long non-coding RNA in human cancers

The ^incidence of cancer is growing worldwide, and it is becoming the most common cause of death. Long non-coding RNAs (lncRNAs) are a group of RNA transcripts with a length larger than 200 nucleotides that cannot encode proteins or peptides. LncRNAs regulate different biological functions by controlling gene expressions at transcriptional, translational, and post-translational levels. Non-coding RNA activated by DNA damage (NORAD) is a highly conserved lncRNA necessary for genome stability. LncRNA NORAD is dysregulated in various types of cancers. This biomarker has been involved in numerous processes associated with carcinogeneses, such as cell proliferation, apoptosis, invasion, and metastasis. In this paper, we reviewed the role of lncRNA NORAD and its biological functions in various human cancers to provide future research insights.

LncRNA NORAD as a Novel Predictor of Lymph Node Metastasis and Prognosis in Solid Tumors: A Systematic Review and Meta-Analysis

Background:

Non-coding RNA-activated by DNA damage (NORAD), a novel identified lncRNA, was found to be aberrantly expressed in various types of cancer. This meta-analysis was performed to evaluate the value of lncRNA NORAD as a prognostic biomarker in human cancers.

Methods:

We searched PubMed, Web of Science, PMC, and Embase databases thoroughly for eligible literatures. Studies which explored the relationship of lncRNA NORAD expression with clinical outcomes in human cancers were included in our meta-analysis. Review Manager version 5.3 and Stata SE 12.0 were used to perform the data analyses.

Results:

Our meta-analysis results indicated that cancer patients with high lncRNA NORAD expression tended to have unfavorable overall survival (OS) (HR = 1.67; 95% CI, 1.44-1.95; P < 0.00001). Moreover, elevated lncRNA NORAD expression showed a significant relationship with poor tumor grade (OR = 1.61; 95% CI, 1.01-2.56; P = 0.05) and more lymph node metastasis (LNM) (OR = 2.66; 95% CI, 1.60-4.43; P = 0.0002).

Conclusions:

LncRNA NORAD could serve as a valuable biomarker to predict poor prognosis and LNM in various human tumors.

LncRNA CRNDE acts as an oncogene in cervical cancer through sponging miR-183 to regulate CCNB1 expression

Studies have identified a series of lncRNAs that contributed to various tumors, although the underlying mechanisms remain largely unclear. We proposed a ceRNA network and investigate relations among lncRNA/miRNA/mRNA in cervical cancer (CC). The genes of differential expression and lncRNA/miRNA/mRNA network were identified by combining TCGA, miRcode, starBase, miRTarBase, miRDB, TargetScan and STRING databases. Meanwhile, the function enrichment was recognized with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Quantitative real time-PCR (qRT-PCR) was performed to determine colorectal neoplasia differentially expressed (CRNDE) expression in CC tissues and cell lines. The effects of CRNDE on the CC biological functions and cyclin B1 (CCNB1) expression were detected by conducting in vitro and in vivo experiments. Quantitative real time-PCR, western blot and dual-luciferase reporter assay were used to predict the target of miR-183. Furthermore, rescue experiments were conducted to further confirm the regulation of CCNB1 by CRNDE. Systematic analyses of bioinformatics from several databases predicted that CRNDE, miR-183 and CCNB1 were in the same network path. Their expressions were up-regulated in CC tissues and cells. Silencing CRNDE-inhibited cell proliferation, migration and invasion, restricted solid tumor growth and promoted cell apoptosis. Moreover, our results suggested that miR-183 targeted the CCNB1 3'UTR and regulated its expression. Additionally, miR-183 mimic could inverse the antitumor function of CRNDE inhibition and partially eliminated the attenuated expression of CCNB1 induced by silencing CRNDE, indicating that CRNDE could positively regulate CCNB1 expression by sponging miR-183. Our study highlighted a role for the CRNDE/miR-183/CCNB1-axis in CC and offered a promising diagnostic strategy for CC treatment.

NORAD orchestrates endometrial cancer progression by sequestering FUBP1 nuclear localization to promote cell apoptosis

Long noncoding RNAs (lncRNAs) are emerging as critical regulators in tumor initiation and progression. However, the biological mechanisms and potential clinical application of lncRNA NORAD in endometrial cancer (EC) remain unknown. Herein, we identified NORAD underwent promoter hypermethylation-associated downregulation in EC. Epigenetic inactivation of NORAD was correlated with EC progression (FIGO stage) and poor outcome. Overexpression of NORAD significantly inhibited cell growth and promoted apoptosis in EC cells. Mechanistic studies revealed that multiple regions of NORAD served as a platform for binding with the central domain of anti-apoptotic factor FUBP1. Our findings further indicated that the NORAD/FUBP1 interaction attenuated FUBP1 nuclear localization and thus impaired the occupancies of FUBP1 on its target pro-apoptotic gene promoters, resulting in apoptosis induction in EC. Moreover, knockdown of NORAD promoted tumor growth in the xenograft mice model. While, introduction of NORAD-4 fragment, which bound with FUBP1, successfully reversed tumor growth and apoptosis inhibition mediated by NORAD knockdown in vivo. Our findings provide mechanistic insight into the critical roles of NORAD as a tumor suppressor in EC progression. NORAD could possibly serve as a novel prognostic biomarker and provide the rationale for EC therapy.

LncRNA NORAD accelerates the progression and doxorubicin resistance of neuroblastoma through up-regulating HDAC8 via sponging miR-144-3p

The dysregulation of non-coding RNAs (ncRNAs) often caused aberrant cell behaviors. In the present study, we focused on the role of long noncoding RNA (lncRNA) non-coding RNA activated by DNA damage (NORAD) in the development of neuroblastoma (NB). The enrichment of NORAD, miRNA-144-3p (miR-144-3p) and histone deacetylase 8 (HDAC8) was measured by quantitative real time polymerase chain reaction (qRT-PCR). The proliferation, chemoresistance, apoptosis, metastasis and autophagy of NB cells were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, transwell migration and invasion assays and Western blot assay, respectively. The target relationship between miR-144-3p and NORAD or HDAC8 was predicted by Starbase software and validated through dual-luciferase reporter assay, RIP and RNA-pull down assays. The protein expression of HDAC8 was measured by Western blot assay. Murine xenograft model was used to verify the function of NORAD in vivo. We found that the level of NORAD was up-regulated in NB tissues and cells, and the level of NORAD was negatively correlated with the prognosis of NB patients. NORAD promoted the proliferation, metastasis and doxorubicin (DOX) resistance while inhibited the apoptosis and autophagy of NB cells. MiR-144-3p was a target of NORAD in NB cells, and NORAD accelerated the progression and DOX resistance of NB through sponging miR-144-3p. HDAC8 was a direct target of miR-144-3p in NB cells, and miR-144-3p suppressed the progression of NB through down-regulating HDAC8. NORAD up-regulated the expression of HDAC8 through sponging miR-144-3p in NB cells. NORAD accelerated the growth of NB tumors at least partly through miR-144-3p/HDAC8 signaling in vivo. In conclusion, NORAD promoted the progression and DOX resistance of NB through miR-144-3p/HDAC8 axis in vivo and in vitro.

LncRNA BBOX1-AS1 upregulates HOXC6 expression through miR-361-3p and HuR to drive cervical cancer progression

Objectives

Over the past years, growing attention has been paid to deciphering the pivotal role of long non‐coding RNAs (lncRNAs) in regulating the occurrence and development of human malignancies, cervical cancer (CC) included. Nonetheless, the regulatory role of lncRNA BBOX1 antisense RNA 1 (BBOX1‐AS1) has not been explored as yet.

Material and Methods

The expression of BBOX1‐AS1 was detected by reverse transcription real‐time quantitative polymerase chain reaction (RT‐qPCR). Cell Counting Kit‐8 (CCK‐8), colony formation, TUNEL, Western blot, transwell and immunofluorescence assays testified the critical role of BBOX1‐AS1 in CC. The relationship between RNAs (BBOX1‐AS1, miR‐361‐3p, HOXC6 and HuR) was analysed by luciferase reporter, RNA Immunoprecipitation (RIP) and RNA pull‐down assays.

Results

BBOX1 antisense RNA 1 antisense RNA 1 was revealed to be highly expressed in CC. Decreased expression of BBOX1‐AS1 had suppressive effects on CC cell growth and migration. Molecular mechanism assays verified that BBOX1‐AS1 had negative interaction with miR‐361‐3p in CC. Additionally, homeobox C6 (HOXC6) was validated to be a downstream target of miR‐361‐3p in CC. Furthermore, ELAV‐like RNA‐binding protein 1, also known as HuR, was uncovered to be capable of regulating the mRNA stability of HOXC6 in CC. More importantly, rescue assays delineated that knockdown of HuR after overexpressing miR‐361‐3p could reverse BBOX1‐AS1 upregulation‐mediated effect on CC progression. Similarly, the function induced by BBOX1‐AS1 upregulation on CC progression could be countervailed by HOXC6 depletion.

Conclusions

BBOX1 antisense RNA 1 facilitates CC progression by upregulating HOXC6 expression via miR‐361‐3p and HuR.

The Role of Long Noncoding RNAs in Human Papillomavirus-associated Pathogenesis

Infections with high-risk human papillomaviruses cause ~5% of all human cancers. E6 and E7 are the only viral genes that are consistently expressed in cancers, and they are necessary for tumor initiation, progression, and maintenance. E6 and E7 encode small proteins that lack intrinsic enzymatic activities and they function by binding to cellular regulatory molecules, thereby subverting normal cellular homeostasis. Much effort has focused on identifying protein targets of the E6 and E7 proteins, but it has been estimated that ~98% of the human transcriptome does not encode proteins. There is a growing interest in studying noncoding RNAs as biochemical targets and biological mediators of human papillomavirus (HPV) E6/E7 oncogenic activities. This review focuses on HPV E6/E7 targeting cellular long noncoding RNAs, a class of biologically versatile molecules that regulate almost every known biological process and how this may contribute to viral oncogenesis.

Long Noncoding RNA DLX6-AS1 Promotes the Progression in Cervical Cancer by Targeting miR-16-5p/ARPP19 Axis

Background: Cervical cancer (CC) is regarded as one of the most common gynecological malignancies. LncRNA DLX6-AS1 has been proven vital in various cancers, whereas its exact function is still largely unestablished in CC. Materials and Methods: The expression pattern of DLX6-AS1 and miR-16-5p in CC cells was determined by real-time quantitative polymerase chain reaction (RT-qPCR). ARPP19 expression was assessed by RT-qPCR and Western blot assays in CC cells. The precise function of DLX6-AS1 in CC was detected by Cell-Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), caspase-3 activity, transwell, and Western blot experiments. RNA immunoprecipitation (RIP) and luciferase reporter assays were employed to certify the combination between miR-16-5p and DLX6-AS1 (or ARPP19). Nuclear cytoplasmic segmentation determined the localization of DLX6-AS1 in CC cells. A xenograft mouse model assay studied the influences of DLX6-AS1 silencing on CC progression in vivo. Results: Elevated DLX6-AS1 expression was disclosed in CC cells. DLX6-AS1 silence attenuated proliferation, migration, and epithelial-mesenchymal transition program as well as enhanced CC cell apoptosis. DLX6-AS1 was uncovered to sponge and negatively modulate miR-16-5p in CC. Besides, ARPP19 was uncovered as a downstream target gene of miR-16-5p in CC. Rescue experiments indicated that DLX6-AS1 enhanced the cellular process of CC cells through upregulating ARPP19. Moreover, in vivo assay confirmed that DLX6-AS1 promoted CC growth. Conclusions: DLX6-AS1 accelerates the progression of CC through sponging miR-16-5p and upregulates ARPP19, which offers a novel insight into prognosis and remedy of CC.

Long non-coding RNA ASB16-AS1 enhances cell proliferation, migration and invasion via functioning as a ceRNA through miR-1305/Wnt/β-catenin axis in cervical cancer

BACKGROUND

Cervical cancer (CC) is one of the most common cancers in women. Long non-coding RNAs (lncRNAs) have been proposed as therapeutic targets in CC. Hence, the present study evaluated the effect of ASB16-AS1 on CC via regulating miR-1305.

METHODS

Differentially expressed lncRNAs associated with CC were screened using bioinformatics database. The expression of ASB16-AS1 and miR-1305 were measured by qRT-PCR in CC tissues and CC cells. Cell proliferation was assessed by CCK-8 and colon formation assays. Cell abilities of migration and invasion were detected by Transwell migration and invasion assays. Luciferase report assays were used to explore the correction between ASB16-AS1, miR-1305 and Wnt2 in CC. Western blot assay detect the activity of Wnt/β-catenin pathway. The xenograft tumor in nude mice was observed to evaluate tumor formation in vivo.

RESULTS

In our study, we showed that the expression of ASB16-AS1 was increased while miR-1305 reduced was re in CC. Clinically, ASB16-AS1 and miR-1305 were correlated with poor-associated clinicopathological features of CC patients. Knockdown of ASB16-AS1 reduced CC cells proliferation, migration and invasion abilities by regulating miR-1305 in vitro and in vivo. Moreover, miR-1305 was directly bound to ASB16-AS1 and Wnt2, regulated their expression negatively. Western blot assays showed that ASB16-AS1 functioned as an oncogene by Wnt/β-catenin pathway.

CONCLUSIONS

This study reveals that ASB16-AS1 promotes cell proliferation, migration, invasion via binding miR-1305 with Wnt2, and enhancing the Wnt/β-catenin pathway. ASB16-AS1 may play a new therapeutic target for CC.

HOXC-AS1-MYC regulatory loop contributes to the growth and metastasis in gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most prevalent and deadly malignancies worldwide. Accumulating reports have indicated the participation of long non-coding RNAs (lncRNAs) in the onset and progression of GC.

METHODS

GSE109476 data was utilized to screen out lncRNAs dysregulated in GC. Gene expressions were determined by qRT-PCR and western blot. Both in vitro and in vivo experiments were carried out to assess the function of HOXC-AS1 in GC. The association between genes was verified via RIP, ChIP, CoIP, RNA pull down and luciferase reporter assays, as appropriate.

RESULTS

HOXC-AS1 was discovered to be upregulated in GC and located both in cytoplasm and in nucleus in GC cells. Functionally, inhibition of HOXC-AS1 restrained GC cell growth and metastasis both in vitro and in vivo. Moreover, HOXC-AS1 was proved to be trans-activated by c-MYC in GC. In return, HOXC-AS1 positively regulated MYC expression in GC through targeting miR-590-3p/MYC axis in cytoplasm and modulating BRG1/β-catenin complex-activated MYC transcription in nucleus. Furthermore, the rescue assays verified that MYC mediated HOXC-AS1-affected GC progression.

CONCLUSION

Our research illustrated a feedback loop of HOXC-AS1-MYC in aggravating GC cell growth and metastasis, highlighting HOXC-AS1 as a promising target for GC diagnosis and treatment.

Long noncoding RNA NORAD is upregulated in epithelial ovarian cancer and its downregulation suppressed cancer cell functions by competing with miR-155-5p

Purpose

In the present study, we evaluated the expression and function of human long noncoding RNA (lncRNA) activated by DNA damage (NORAD) in human epithelial ovarian cancer (EOC).

Methods

NORAD expression was evaluated by qRT‐PCR in EOC cell lines and in situ EOC clinical samples. Lentivirus‐mediated NORAD downregulation was conducted in OVCAR‐3 and ES‐2 cells, and its effect on cancer cell proliferation, bufalin chemoresistance, cell‐cycle transition in vitro, and xenotransplantation in vivo were examined, respectively. The likelihood of an lncRNA‐microRNA (miRNA) signaling pathway was examined by probing the possible downstream competing target of NORAD, hsa‐miR‐155‐5p. Moreover, hsa‐miR‐155‐5p was knocked down in NORAD‐downregulated EOC cells to functionally evaluate the correlation between NORAD and hsa‐miR‐155‐5p in EOC.

Results

We found that NORAD was substantially upregulated in both EOC cell lines and human tumors. In OVCAR‐3 and ES‐2 cells, lentivirus‐mediated NORAD downregulation had significant anticancer effects, as it suppressed cell proliferation, decreased bufalin chemoresistance, arrested cell‐cycle transition, and inhibited xenograft growth. Also, hsa‐miR‐155‐5p was confirmed to be the competing target of NORAD in EOC, and its knockdown in OVCAR‐3 and ES‐2 cells reversed the NORAD downregulation‐induced anticancer functions.

Conclusions

NORAD is upregulated in EOC. Inhibition of NORAD, possibly through endogenously competing against hsa‐miR‐155‐5p, can be a new tumor‐suppressing strategy in EOC.

Long non-coding RNA NORAD promotes the occurrence and development of non-small cell lung cancer by adsorbing MiR-656-3p

Background

To explore the role of non‐coding RNA activated by DNA damage (NORAD), a long non‐coding ribonucleic acid (lncRNA), in non‐small cell lung cancer (NSCLC) and its possible mechanism.

Methods

Quantitative real‐time polymerase chain reaction was adopted for the detection of the expression levels of NORAD, micro RNA (miR)‐656‐3p, and AKT serine/threonine kinase 1 (AKT1). The effects of NORAD, miR‐656‐3p, and AKT1 on cell proliferation and migration were examined through the Cell Counting Kit‐8 (CCK‐8) and Transwell assay. Subsequently, the binding relationships between miR‐656‐3p and AKT1 and between miR‐656‐3p and NORAD were verified by dual‐luciferase reporter gene assay. Finally, the potential mechanisms of action of NORAD and miR‐656‐3p were explored through the torsion experiment.

Results

The lncRNA NORAD expression level in NSCLC patients was notably higher than that in people in control group, that in patients with metastasis was higher than that in patients without metastasis, and that in patients with NSCLC in stage III‐IV was significantly higher than that in patients with NSCLC in stage I‐II. Elevation of NORAD stimulated the proliferation and migration of NSCLC A549/H460 cells. According to the reporter gene assay, NORAD could bind to miR‐656‐3p. Besides, miR‐656‐3p was significantly under‐expressed in cancer tissues of patients with NSCLC, and overexpression of miR‐656‐3p could block the proliferation and migration of A549/H460 cells and reversed promotion on cell proliferation and migration by NORAD. Furthermore, the reporter gene assay revealed that the overexpression of AKT1, a miR‐656‐3p target gene, could reverse miR‐656‐3p's inhibitory effect on the proliferation and migration of A549/H460 cells.

Conclusion

LncRNA NORAD is capable of promoting the proliferation and migration of NSCLC cells, and its mechanism may be that it increases the AKT1 expression by adsorbing miR‐656‐3p.

Clinically Relevant Biomarker Discovery in High-Risk Recurrent Neuroblastoma

Neuroblastoma is a pediatric cancer of the developing sympathetic nervous system. High-risk neuroblastoma patients typically undergo an initial remission in response to treatment, followed by recurrence of aggressive tumors that have become refractory to further treatment. The need for biomarkers that can select patients not responding well to therapy in an early phase is therefore needed. In this study, we used next generation sequencing technology to determine the expression profiles in high-risk neuroblastoma cell lines established before and after therapy. Using partial least squares-discriminant analysis (PLS-DA) with least absolute shrinkage and selection operator (LASSO) and leave-one-out cross-validation, we identified a panel of 55 messenger RNAs and 17 long non-coding RNAs (lncRNAs) which were significantly altered in the expression between cell lines isolated from primary and recurrent tumors. From a neuroblastoma patient cohort, we found 20 of the 55 protein-coding genes to be differentially expressed in patients with unfavorable compared with favorable outcome. We further found a twofold increase or decrease in hazard ratios in these genes when comparing patients with unfavorable and favorable outcome. Gene set enrichment analysis (GSEA) revealed that these genes were involved in proliferation, differentiation and regulated by Polycomb group (PcG) proteins. Of the 17 lncRNAs, 3 upregulated (NEAT1, SH3BP5-AS1, NORAD) and 3 downregulated lncRNAs (DUBR, MEG3, DHRS4-AS1) were also found to be differentially expressed in favorable compared with unfavorable outcome. Moreover, using expression profiles on both miRNAs and mRNAs in the same cohort of cell lines, we found 13 downregulated and 18 upregulated experimentally observed miRNA target genes targeted by miR-21, -424 and -30e, -29b, -138, -494, -181a, -34a, -29b, respectively. The advantage of analyzing biomarkers in a clinically relevant neuroblastoma model system enables further studies on the effect of individual genes upon gene perturbation. In summary, this study identified several genes, which may aid in the prediction of response to therapy and tumor recurrence.

The long noncoding RNA NORAD enhances the TGF-β pathway to promote hepatocellular carcinoma progression by targeting miR-202-5p

Hepatocellular carcinoma (HCC) is one of the most fatal cancers with common features of invasion and metastasis. Recent evidence indicate that the long noncoding RNA NORAD is a potential oncogene and is significantly upregulated in several cancers. However, the general biological role and clinical value of NORAD in HCC remains unknown. Here, NORAD expression was measured in 29 paired tumor and paratumor tissues via quantitative real-time polymerase chain reaction (qPCR). The effects of NORAD on HCC cell malignant potential were investigated via NORAD overexpression and knockdown both in vitro and in vivo. The mechanism of competitive endogenous RNAs (ceRNAs) was acquired and identified by bioinformatics analyses and luciferase assays. Moreover, the impact of NORAD level on the transforming growth factor β (TGF-β) pathway was further determined by qPCR. We found that HCC tissues had a high level of NORAD compared with the paratumor tissues, and NORAD upregulation was associated with the shorter overall survival of patients with HCC. Furthermore, NORAD overexpression was demonstrated to promote HCC cell migration and invasion. Mechanically, NORAD might function as a ceRNA to regulate miR-202-5p, which served as a tumor-suppressing microRNA via the TGF-β pathway. We address that NORAD has a tumor-promoting effect in HCC and describes a novel mechanism whereby NORAD regulates the TGF-β pathway as a ceRNA of Homo sapiens (hsa)-miR-202-5p.

Long Non-coding RNA DLEU1 Promotes Proliferation and Invasion by Interacting With miR-381 and Enhancing HOXA13 Expression in Cervical Cancer

Although growing evidence has demonstrated that the long non-coding RNA DLEU1 is involved in the progression of various cancers, its functional role and underlying mechanisms have not been explored in cervical cancer (CC). In this study, we found that DLEU1 was up-regulated in both CC tissues and CC cell lines, and overexpression of DLEU1 was significantly correlated with shorter patient survival. Knockdown of DLEU1 suppressed CC cell proliferation and invasion, whereas overexpression of DLEU1 promoted the proliferation and invasion of CC cells. Bioinformatics analysis was used to elucidate the potential correlation between DLEU1 and miR-381. Moreover, qRT-PCR analysis, luciferase reporter assay and RNA immunoprecipitation assay confirmed that DLEU1 inhibited the expression of miR-381, and revealed a direct interaction between DLEU1 and miR-381. In addition, we demonstrated that miR-381 directly targeted HOXA13 in CC cells. The restoration of HOXA13 expression reversed DLEU1 knockdown or miR-381 overexpression-mediated suppression of cell proliferation and invasion. These results suggested that DLEU1 can promote CC cell proliferation and invasion via the miR-381/HOXA13 axis.