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

Role of cell division cycle-associated proteins in regulating cell cycle and promoting tumor progression

The cell division cycle-associated protein (CDCA) family is important in regulating cell division. High CDCA expression is significantly linked to tumor development. This review summarizes clinical and basic studies on CDCAs conducted in recent decades. Furthermore, it systematically introduces the molecular expression and function, key mechanisms, cell cycle regulation, and roles of CDCAs in tumor development, cell proliferation, drug resistance, invasion, and metastasis. Additionally, it presents the latest research on tumor diagnosis, prognosis, and treatment targeting CDCAs. These findings are pivotal for further in-depth studies on the role of CDCAs in promoting tumor development and provide theoretical support for their application as new anti-tumor targets.

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.

Identification of an immune-related 6-lncRNA panel with a good performance for prognostic prediction in hepatocellular carcinoma by integrated bioinformatics analysis

Hepatocellular carcinoma (HCC) is one of the most malignant tumors with a poor prognosis. The long non-coding RNA (lncRNA) has been found to have great potential as a prognostic biomarker or therapeutic target for cancer patients. However, the prognostic value and tumor immune infiltration of lncRNAs in HCC has yet to be fully elucidated. To identify prognostic biomarkers of lncRNA in HCC by integrated bioinformatics analysis and explore their functions and relationship with tumor immune infiltration. The prognostic risk assessment model for HCC was constructed by comprehensively using univariate/multivariate Cox regression analysis, Kaplan-Meier survival analysis, and the least absolute shrinkage and selection operator regression analysis. Subsequently, the accuracy, independence, and sensitivity of our model were evaluated, and a nomogram for individual prediction in the clinic was constructed. Tumor immune microenvironment (TIME), immune checkpoints, and human leukocyte antigen alleles were compared in high- and low-risk patients. Finally, the functions of our lncRNA signature were examined using Gene Ontology, Kyoto Encyclopedia of Genes and Genomes enrichment analysis, and gene set enrichment analysis. A 6-lncRNA panel of HCC consisting of RHPN1-AS1, LINC01224, CTD-2510F5.4, RP1-228H13.5, LINC01011, and RP11-324I22.4 was eventually identified, and show good performance in predicting the survivals of patients with HCC and distinguishing the immunomodulation of TIME of high- and low-risk patients. Functional analysis also suggested that this 6-lncRNA panel may play an essential role in promoting tumor progression and immune regulation of TIME. In this study, 6 potential lncRNAs were identified as the prognostic biomarkers in HCC, and the regulatory mechanisms involved in HCC were initially explored.

Immunohistochemical scoring of LAG-3 in conjunction with CD8 in the tumor microenvironment predicts response to immunotherapy in hepatocellular carcinoma

Introduction

Immune checkpoint blockade (ICB) is a systemic therapeutic option for advanced hepatocellular carcinoma (HCC). However, low patient response rates necessitate the development of robust predictive biomarkers that identify individuals who will benefit from ICB. A 4-gene inflammatory signature, comprising CD8, PD-L1, LAG-3, and STAT1, was recently shown to be associated with a better overall response to ICB in various cancer types. Here, we examined whether tissue protein expression of CD8, PD-L1, LAG-3, and STAT1 predicts response to ICB in HCC.

Methods

HCC samples from 191 Asian patients, comprising resection specimens from 124 patients (ICB-naïve) and pre-treatment specimens from 67 advanced HCC patients treated with ICB (ICB-treated), were analyzed for CD8, PD-L1, LAG-3, and STAT1 tissue expression using multiplex immunohistochemistry followed by statistical and survival analyses.

Results

Immunohistochemical and survival analyses of ICB-naïve samples showed that high LAG-3 expression was associated with shorter median progression-free survival (mPFS) and overall survival (mOS). Analysis of ICB-treated samples revealed that high proportions of LAG-3⁺ and LAG-3⁺CD8⁺ cells pre-treatment were most closely associated with longer mPFS and mOS. Using a log-likelihood model, adding the total LAG-3⁺ cell proportion to the total CD8⁺ cell proportion significantly increased the predictive values for mPFS and mOS, compared with the total CD8⁺ cell proportion alone. Moreover, levels of CD8 and STAT1, but not PD-L1, were significantly correlated with better responses to ICB. After analyzing viral-related and non-viral HCC samples separately, only the LAG3⁺CD8⁺ cell proportion was significantly associated with responses to ICB regardless of viral status.

Conclusion

Immunohistochemical scoring of pre-treatment levels of LAG-3 and CD8 in the tumor microenvironment may help predict ICB benefits in HCC patients. Furthermore, immunohistochemistry-based techniques offer the advantage of being readily translatable in the clinical setting.

Making Sense of Antisense lncRNAs in Hepatocellular Carcinoma

Transcriptome complexity is emerging as an unprecedented and fascinating domain, especially by high-throughput sequencing technologies that have unveiled a plethora of new non-coding RNA biotypes. This review covers antisense long non-coding RNAs, i.e., lncRNAs transcribed from the opposite strand of other known genes, and their role in hepatocellular carcinoma (HCC). Several sense-antisense transcript pairs have been recently annotated, especially from mammalian genomes, and an understanding of their evolutionary sense and functional role for human health and diseases is only beginning. Antisense lncRNAs dysregulation is significantly involved in hepatocarcinogenesis, where they can act as oncogenes or oncosuppressors, thus playing a key role in tumor onset, progression, and chemoradiotherapy response, as deduced from many studies discussed here. Mechanistically, antisense lncRNAs regulate gene expression by exploiting various molecular mechanisms shared with other ncRNA molecules, and exploit special mechanisms on their corresponding sense gene due to sequence complementarity, thus exerting epigenetic, transcriptional, post-transcriptional, and translational controls. The next challenges will be piecing together the complex RNA regulatory networks driven by antisense lncRNAs and, ultimately, assigning them a function in physiological and pathological contexts, in addition to defining prospective novel therapeutic targets and innovative diagnostic tools.

Identification of Hypoxia-Related Prognostic Signature and Competing Endogenous RNA Regulatory Axes in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common type of liver cancer and one of the highly lethal diseases worldwide. Hypoxia plays an important role in the development and prognosis of HCC. This study aimed to construct a new hypoxia-related prognosis signature and investigate its potential ceRNA axes in HCC. RNA profiles and hypoxia genes were downloaded, respectively, from the Cancer Genome Atlas hepatocellular carcinoma database and Gene Set Enrichment Analysis website. Cox regression analyses were performed to select the prognostic genes and construct the risk model. The ENCORI database was applied to build the lncRNA-miRNA-mRNA prognosis-related network. The TIMER and CellMiner databases were employed to analyze the association of gene expression in ceRNA with immune infiltration and drug sensitivity, respectively. Finally, the co-expression analysis was carried out to construct the potential lncRNA/miRNA/mRNA regulatory axes. We obtained a prognostic signature including eight hypoxia genes (ENO2, KDELR3, PFKP, SLC2A1, PGF, PPFIA4, SAP30, and TKTL1) and further established a hypoxia-related prognostic ceRNA network including 17 lncRNAs, six miRNAs, and seven mRNAs for hepatocellular carcinoma. Then, the analysis of immune infiltration and drug sensitivity showed that gene expression in the ceRNA network was significantly correlated with the infiltration abundance of multiple immune cells, the expression level of immune checkpoints, and drug sensitivity. Finally, we identified three ceRNA regulatory axes (SNHG1/miR-101-3p/PPFIA4, SNHG1/miR-101-3p/SAP30, and SNHG1/miR-101-3p/TKTL1) associated with the progression of HCC under hypoxia. Here, we constructed a prognosis gene signature and a ceRNA network related to hypoxia for hepatocellular carcinoma. Among the ceRNA network, six highly expressed lncRNAs (AC005540.1, AC012146.1, AC073529.1, AC090772.3, AC138150.2, AL390728.6) and one highly expressed mRNA (PPFIA4) were the potential biomarkers of hepatocellular carcinoma which we firstly reported. The three predicted hypoxia-related regulatory axes may play a vital role in the progression of hepatocellular carcinoma.

A ferroptosis-associated lncRNAs signature predicts the prognosis of hepatocellular carcinoma

BACKGROUND

Long noncoding RNAs (lncRNAs) have been implicated in the development of hepatocellular carcinoma (HCC). Mounting evidence shows that lncRNAs can be used as prognostic biomarkers of HCC. Here, we developed a multi-lncRNA prognostic signature comprising ferroptosis-related lncRNAs in HCC.

METHODS

Gene expression data and clinical information of HCC were obtained from the TCGA dataset. Differentially expressed genes of ferroptosis (DE-Ferrs) were screened. Correlation analysis was carried between lncRNAs and DE-Ferrs to identify ferroptosis-related lncRNAs. lncRNAs associated with prognosis and ferroptosis were identified using Univariate Cox analysis. Data from a TCGA dataset were randomly grouped into training and verification sets. The least absolute shrinkage and selection operator method analysis was carried out to identify lncRNAs with prognostic value. These lncRNAs were used to construct a prognostic signature using the training set. The signature was validated in the verification set.

RESULTS

A total of 90 DE-Ferrs-related lncRNAs were identified which were significantly correlated with HCC prognosis. Seven lncRNAs were used to construct a 7-lncRNA signature. The area under the curves for 1-, 3-, and 5-year overall survival (OS) were 0.748, 0.681, and 0.659 in the training set, and 0.791, 0.731, and 0.815 in the validation set, respectively. The results demonstrated that a high-risk score was significantly associated with a high tumor grade, high infiltration of macrophages and fibroblasts in the tumor, and high expression of m6A methylation regulatory factors. A nomogram was constructed using the risk score and clinical features for predicting the prognosis of HCC. The nomogram showed high prediction accuracy.

CONCLUSION

In conclusion, the established 7 ferroptosis-related lncRNAs signature can accurately predict HCC prognosis.

The LncRNA MIR155HG is Upregulated by SP1 in Melanoma Cells and Drives Melanoma Progression via Modulating the MiR-485-3p/PSIP1 Axis

BACKGROUND

MIR155HG is a long non-coding RNA (lncRNA) that has been shown to be dysregulated in a range of tumor types, but the functions of this lncRNA in melanoma remain to be explored.

OBJECTIVES

We explored the functions of lncRNA MIR155HG in melanoma progression.

METHODS

The expression of miR155HG was analyzed in clinical melanoma. Bioinformatics analysis was performed to assess the potential tumor-related functions of miR155HG. The interaction of miR155HG and SP1 and the inhibition of PSIP1 by miR-485-3p were analyzed by ChIP, luciferase reporter experiments, and the biological effects in melanoma were explored by colony formation assays, EdU cell proliferation assays, Transwell analysis, and intracranial melanoma mouse model.

RESULTS

Herein, we found that MIR155HG was markedly upregulated in melanoma cell lines and tissues. We further determined that the SP1 transcription factor was responsible for driving MIR155HG upregulation in melanoma. Elevated MIR155HG levels were linked to decreased overall survival (OS) in melanoma patients, and we further determined that MIR155HG expression was an independent predictor of melanoma patient prognosis. When MIR155HG was knocked down in melanoma cells, this impaired their proliferative, migratory, and invasive activity. By using predictive bioinformatics analyses, we identified miR-485-3p as a microRNA (miRNA) capable of binding to both MIR155HG and the 3' UTR of PSIP1.

CONCLUSION

Together, these results suggest that MIR155HG is capable of promoting melanoma cell proliferation via the miR-485-3p/PSIP1 axis. These novel findings provide new insights into the development of melanoma, potentially highlighting future avenues for therapeutic intervention.

The Association between Long Noncoding RNA over Expression and Poor Prognosis of Liver Cancer: A Meta-Analysis

BACKGROUND

Long noncoding RNA (lncRNA) is considered to be a mediator of carcinogenesis, which may be associated with liver cancer survival. However, the relationship remains inconclusive. Meta-analysis was conducted to analytically review the association between the lncRNA expression level and clinicopathological characteristics and prognostic value of hepatic carcinoma.

MATERIALS AND METHODS

Four databases including Embase, PubMed, Web of Science, and the Cochrane Library were searched to collect studies about the relation between lncRNA overexpression and prognosis of liver cancer, dating from the earliest records of these databases to March 2021. Two researchers independently screened the data and literature to perform a stringent evaluation of the quality of material involved in the study. Meta-analysis was performed by Stata 16.0 software on 42 case-control studies with 6293 samples.

RESULTS

The outcomes of meta-analysis are presented as follows: lncRNA overexpression patients had later TNM stage (OR = 0.36, 95% CI (0.31, 0.41), P < 0.001), lower histological grade (OR = 0.56, 95%CI (0.49, 0.65), P < 0.001), more vascular invasion (OR = 2.02, 95% CI (1.74, 2.35), P < 0.001), bigger tumor size (OR = 2.28, 95% CI (2.00, 2.60), P < 0.001), more severe liver cirrhosis (OR = 1.39, 95% CI(0.1.16, 1.66), P < 0.001), more likely to metastasize (OR = 1.80, 95%CI(1.49, 2.18), P < 0.001), and more tumor numbers (OR = 0.72, 95% CI (0.62, 0.84), P < 0.05). lncRNA over expression patients had shorter OS (HR = 2.32, 95 CI% (2.08, 2.59), P < 0.01, RFS (HR = 2.19, 95 CI% (1.72, 2.78), P < 0.01), and DFS (HR = 2.01, 95 CI% (1.57, 2.57), P < 0.01).

CONCLUSIONS

Overexposure of lncRNA is a poor prognostic feature for patients with hepatic carcinoma. The scope of our study was limited because of a lack of relevant research and the poor representativeness and varying quality of the studies involved in the current meta-analysis. Our conclusion still requires higher studies for further validation. This trial is clinically registered with CRD4201920620.

The Association between Long Noncoding RNA over Expression and Poor Prognosis of Liver Cancer: A Meta-Analysis

Background

Long noncoding RNA (lncRNA) is considered to be a mediator of carcinogenesis, which may be associated with liver cancer survival. However, the relationship remains inconclusive. Meta-analysis was conducted to analytically review the association between the lncRNA expression level and clinicopathological characteristics and prognostic value of hepatic carcinoma.

Materials and Methods

Four databases including Embase, PubMed, Web of Science, and the Cochrane Library were searched to collect studies about the relation between lncRNA overexpression and prognosis of liver cancer, dating from the earliest records of these databases to March 2021. Two researchers independently screened the data and literature to perform a stringent evaluation of the quality of material involved in the study. Meta-analysis was performed by Stata 16.0 software on 42 case-control studies with 6293 samples.

Results

The outcomes of meta-analysis are presented as follows: lncRNA overexpression patients had later TNM stage (OR = 0.36, 95% CI (0.31, 0.41), P < 0.001), lower histological grade (OR = 0.56, 95%CI (0.49, 0.65), P < 0.001), more vascular invasion (OR = 2.02, 95% CI (1.74, 2.35), P < 0.001), bigger tumor size (OR = 2.28, 95% CI (2.00, 2.60), P < 0.001), more severe liver cirrhosis (OR = 1.39, 95% CI(0.1.16, 1.66), P < 0.001), more likely to metastasize (OR = 1.80, 95%CI(1.49, 2.18), P < 0.001), and more tumor numbers (OR = 0.72, 95% CI (0.62, 0.84), P < 0.05). lncRNA over expression patients had shorter OS (HR = 2.32, 95 CI% (2.08, 2.59), P < 0.01, RFS (HR = 2.19, 95 CI% (1.72, 2.78), P < 0.01), and DFS (HR = 2.01, 95 CI% (1.57, 2.57), P < 0.01).

Conclusions

Overexposure of lncRNA is a poor prognostic feature for patients with hepatic carcinoma. The scope of our study was limited because of a lack of relevant research and the poor representativeness and varying quality of the studies involved in the current meta-analysis. Our conclusion still requires higher studies for further validation. This trial is clinically registered with CRD4201920620.

The Cohesin Complex and Its Interplay with Non-Coding RNAs

The cohesin complex is a multi-subunit protein complex initially discovered for its role in sister chromatid cohesion. However, cohesin also has several other functions and plays important roles in transcriptional regulation, DNA double strand break repair, and chromosome architecture thereby influencing gene expression and development in organisms from yeast to man. While most of these functions rely on protein–protein interactions, post-translational protein, as well as DNA modifications, non-coding RNAs are emerging as additional players that facilitate and modulate the function or expression of cohesin and its individual components. This review provides a condensed overview about the architecture as well as the function of the cohesin complex and highlights its multifaceted interplay with both short and long non-coding RNAs.

RHPN1‑AS1 promotes ovarian carcinogenesis by sponging miR‑6884‑5p thus releasing TOP2A mRNA

Ovarian cancer, a severe lethal gynecological malignancy, is characterized by both high morbidity and mortality. Long noncoding RNAs (lncRNAs) have recently caused extensive concern due to their regulatory function in various human tumors. There are a mounting number of lncRNAs that are in extreme need of research, serving as biomarkers for diagnosis and therapy for ovarian cancer. In the present study, RT-qPCR was employed to detect how Rhophilin Rho GTPase binding protein 1 antisense RNA1 (RHPN1-AS1), miR-6884-5p and DNA topoisomerase IIα (TOP2A) are expressed in ovarian cancer tissues or cell lines. BrdU, MTT, colony formation and cell adhesion assays, caspase-3 activity, flow cytometry and wound healing assay were employed to assess cell proliferation, viability, colony number, adhesion, apoptosis and migration in ovarian cancer, respectively. RHPN1-AS1 was determined to be enriched in ovarian cancer tissues and cell lines. Silencing of RHPN1-AS1 was reported to increase cell apoptosis and impair cell proliferation, viability, colony number, adhesion and migration in vitro. Furthermore, RHPN1-AS1 was able to sponge miR-6884-5p which directly targets TOP2A in ovarian cancer. Notably, silencing of RHPN1-AS1 functionally reversed the oncogenic effect induced by the miR-6884-5p inhibitor, while the miR-6884-5p inhibitor markedly restored the inhibition of ovarian carcinogenesis modulated by silencing TOP2A in ovarian cancer. RHPN1-AS1 was found to promote ovarian carcinogenesis via sponging miR-6884-5p thus releasing TOP2A, and RHPN1-AS1 may act as a promising biomarker for the prognosis and therapy of ovarian cancer.

Identification and analysis of genes associated with epithelial ovarian cancer by integrated bioinformatics methods

Background

Though considerable efforts have been made to improve the treatment of epithelial ovarian cancer (EOC), the prognosis of patients has remained poor. Identifying differentially expressed genes (DEGs) involved in EOC progression and exploiting them as novel biomarkers or therapeutic targets is of great value.

Methods

Overlapping DEGs were screened out from three independent gene expression omnibus (GEO) datasets and were subjected to Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses. The protein-protein interactions (PPI) network of DEGs was constructed based on the STRING database. The expression of hub genes was validated in GEPIA and GEO. The relationship of hub genes expression with tumor stage and overall survival and progression-free survival of EOC patients was investigated using the cancer genome atlas data.

Results

A total of 306 DEGs were identified, including 265 up-regulated and 41 down-regulated. Through PPI network analysis, the top 20 genes were screened out, among which 4 hub genes, which were not researched in depth so far, were selected after literature retrieval, including CDC45, CDCA5, KIF4A, ESPL1. The four genes were up-regulated in EOC tissues compared with normal tissues, but their expression decreased gradually with the continuous progression of EOC. Survival curves illustrated that patients with a lower level of CDCA5 and ESPL1 had better overall survival and progression-free survival statistically.

Conclusion

Two hub genes, CDCA5 and ESPL1, identified as probably playing tumor-promotive roles, have great potential to be utilized as novel therapeutic targets for EOC treatment.

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.

lncRNAHIF1A-AS2 Promotes Renal Carcinoma Cell Proliferation and Migration via miR-130a-5p/ERBB2 Pathway

Background

Long non-coding RNAs (lncRNAs) are essential for tumorigenesis and progression of diverse cancers. This study aims to investigate the roles of lncRNAs on renal carcinoma.

Methods

The expression of lncRNA HIF1A-AS2 in clear cell renal cell carcinoma (ccRCC) and adjacent non-cancer tissues was identified by quantitative real-time PCR (qRT-PCR). Investigations were performed on biological function of lncRNA HIF1A-AS2 on cell proliferation, cell cycle, apoptosis and invasion of ccRCC by overexpression and knockdown experiments. Further, luciferase reporter assay and Western blot were constructed to explore molecular mechanisms underlying the function of lncRNA HIF1A-AS2.

Results

HIF1A-AS2 was highly expressed in kidney cancer tissues and ccRCC cells. Interference of HIF1A-AS2 in vivo hindered cell proliferation, invasion and migration while accelerated cell apoptosis. Overexpression of HIF1A-AS2 presented an opposite effect that repressed the expression of miR-130a-5p, and miR-130a-5p inhibited the expression of HIF1A-AS2. Additionally, rescue experiments exhibited that oncogenic function of HIF1A-AS2 was partially dependent on the suppression of miR-130a-5p.

Conclusion

Our results indicated a critical role for the HIF1A-AS2-miR-130a-5p axis in renal carcinoma progression, which may act as a promising diagnostic biomarker and a pivotal therapeutic target for renal carcinoma cures.

Long Non-Coding RNA NEAT1 Promotes the Proliferation, Migration, and Metastasis of Human Breast-Cancer Cells by Inhibiting miR-146b-5p Expression

Background

Breast cancer (BC) is the most commonly diagnosed cancer in women. Tumor recurrence and metastasis are the key causes of death in BC patients. Long non-coding RNA (lncRNA) is closely associated with BC progression. lncRNA nuclear-enriched abundant transcript (NEAT)1 has been reported to regulate the proliferation and mobility of several types of cancer cells. However, how lncRNA NEAT1 affects the proliferation and invasion of BC cells is not known.

Methods

Quantitative real time-polymerase chain reaction (qRT-PCR) was used to measure expression of lncRNA NEAT1 and microRNA (miR)-146b-5p in BC tissues and cell lines. Cell Counting Kit (CCK)-8, cell colony-formation, wound-healing, and Transwell™ assays were undertaken to determine the effects of lncRNA NEAT1 and miR-146b-5p on progression of BC cells. The interaction between lncRNA NEAT1 and miR-146b-5p was examined by luciferase reporter, RNA-binding protein immunoprecipitation (RIP), and RNA-pulldown assays.

Results

Expression of lncRNA NEAT1 was upregulated in BC tissues and cell lines. High expression of lncRNA NEAT1 predicted poor overall survival in BC patients. Silencing of expression of lncRNA NEAT1 inhibited epithelial–mesenchymal transition (EMT) and suppressed the proliferation, migration and invasion of BC cells. Ectopic expression of lncRNA NEAT1 induced EMT and promoted BC progression. Mechanistic investigations revealed that miR-146b-5p was a direct target of lncRNA NEAT1, and its expression was correlated negatively with expression of lncRNA NEAT1 in BC tissues.

Conclusion

lncRNA NEAT1 could (i) serve as a novel prognostic marker for BC and (ii) be a potential therapeutic target for BC.