Expression and clinicopathological significance of the lncRNA HOXA11-AS in colorectal cancer

Long non-coding RNAs as pathophysiological regulators, therapeutic targets and novel extracellular vesicle biomarkers for the diagnosis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic relapsing disease of the gastrointestinal (GI) system that includes two groups, Crohn's disease (CD) and ulcerative colitis (UC). To cope with these two classes of IBD, the investigation of pathogenic mechanisms and the discovery of new diagnostic and therapeutic approaches are crucial. Long non-coding RNAs (lncRNAs) which are non-coding RNAs with a length of longer than 200 nucleotides have indicated significant association with the pathology of IBD and strong potential to be used as accurate biomarkers in diagnosing and predicting responses to the IBD treatment. In the current review, we aim to investigate the role of lncRNAs in the pathology and development of IBD. We first describe recent advances in research on dysregulated lncRNAs in the pathogenesis of IBD from the perspective of epithelial barrier function, intestinal immunity, mitochondrial function, and intestinal autophagy. Then, we highlight the possible translational role of lncRNAs as therapeutic targets, diagnostic biomarkers, and predictors of therapeutic response in colon tissues and plasma samples. Finally, we discuss the potential of extracellular vesicles and their lncRNA cargo in the pathophysiology, diagnosis, and treatment of IBD.

Down-regulation of long noncoding RNA HOXA11-AS nullifies the impact of microRNA-506-3p on chondrocytes proliferation and apoptosis in osteoarthritis

OBJECTIVES

This study was directed towards exploring the impacts of lncRNA HOXA11-AS-mediated microRNA (miR)-506-3p on chondrocytes proliferation and apoptosis in osteoarthritis (OA).

METHODS

The articular cartilages were provided by OA patients who received total knee arthroplasty, and Human Chondrocyte (HC)-OA (HCOA) was also attained. The miR-506-3p and HOXA11-AS expressions in articular cartilages from OA patients and HCOA cells were analyzed via qPCR. After gain- and loss-of-function assays in HCOA cells, MTT assay and flow cytometry (FC) were used for assessing cell viability and apoptosis, accordingly. The levels of PIK3CA, AKT, and mTOR as well as AKT and mTOR phosphorylation levels assessed using western blotting (WB). The targeting correlation of HOXA11-AS and miR-506-3p as well as miR-506-3p and PIK3CA was assessed through Dual-Luciferase Reporter gene Assay (DLRA).

RESULT

The articular cartilages from OA patients and Human Chondrocyte (HC)-OA (HCOA) cells showed increased HOXA11-AS and decreased miR-506-3p. Mechanistically, HOXA11-AS was capable of binding to miR-506-3p to increase PIK3CA, the target gene of miR-506-3p. miR-506-3p suppression facilitated HCOA cell proliferation and reduced their apoptosis, which was nullified by further silencing HOXA11-AS or silencing PIK3CA. The down-regulation of HOXA11-AS disrupted the PI3K/AKT/mTOR pathway, which was counteracted by further miR-506-3p inhibition.

CONCLUSION

The silencing of HOXA11-AS might block the PI3K/AKT/mTOR pathway through miR-506-3p up-regulation, thereby restricting HCOA cell proliferation and provoking apoptosis.

The minor allele of rs17427875 in long non-coding RNA-HOXA11-AS influences the prognosis of subarachnoid hemorrhage (SAH) via modulating miR-15a and STAT3 expression

Background: HOAX11-AS was reported to promote the progression of liver cancer via the signaling pathway of miR-15a-3p/STAT3. In this study, we investigated the effect of rs17427875 on the prognosis of subarachnoid hemorrhage (SAH) and its underlying molecular mechanisms.

Methods: 158 SAH patients were recruited and grouped according to their genotypes rs17427875. Peripheral blood and cerebrospinal fluid (CSF) samples were collected for subsequent analysis. Quantitative real-time PCR, luciferase assays, Western blot and ELISA were performed to analyze the correlations between the expression of lncRNA-HOXA11-AS, miR-15a, TNF-α and NF-κB.

Results: The survival rate was remarkably higher in SAH patients carrying the AA genotype of rs17427875 when compared with those carrying the AT genotype. The expression of miR-15a was significantly repressed in the peripheral blood and CSF of SAH patients carrying the AT allele when compared with that in patients carrying the AA allele. MiR-15a showed a remarkable efficacy in inhibiting the luciferase activity of wild type lncRNA-HOXA11-AS and STAT3 in THP-1 cells. P-HOXA11-AS-T showed a stronger ability to suppress the expression of miR-15a and activate the expression of STAT3, TNF-α and NF-κB in THP-1 cells when compared with P-HOXA11-AS-A.

Conclusions: The findings demonstrated that the presence of the minor allele of rs17427875 in lncRNA-HOXA11-AS could increase the expression level of lncRNA-HOXA11-AS, thus elevating the expression level of STAT3 via down-regulating miR-15a, and increased STAT3 expression could aggravate inflammation to cause poor prognosis of SAH. Therefore, the rs17427875 polymorphism can be used as a potential biomarker for the prognosis of SAH.

Inconsistency in the expression pattern of a five-lncRNA signature as a potential diagnostic biomarker for gastric cancer patients in bioinformatics and in vitro

Objectives

Due to diagnosis of gastric cancer in advanced stages as well as its poor prognosis, finding biomarkers is essential. In this study, using the TCGA RNAseq data of gastric cancer patients, we evaluated the diagnostic value of lncRNAs that had differential expression.

Materials and Methods

We evaluated P-value, FDR, and log fold change for whole transcripts. Next, by comparison of the RNAseq gene names with the total known lncRNA names, we identified differential expressed lncRNAs. Following this, specificity and sensitivity for lncRNAs coming from the previous step were calculated. For more confirmation, we predicted target genes and performed GO and KEGG signaling pathway analysis. In the end, we examined reliability and consistency of expression of this signature in three gastric cancer cell lines and one of them in twenty tumors and tumor-adjacent normal tissue samples using qRT-PCR.

Results

Five lncRNAs had proper sensitivity and specificity and had target genes involved in cancer-related signaling pathways; however, they showed different expression patterns in TCGA data and in vitro.

Conclusion

The results of our study demonstrated that the five-lncRNAs PART1, UCA1, DIRC3, HOTAIR, and HOXA11AS require more investigation to be confirmed as diagnostic biomarkers in gastric cancer.

The long non-coding RNA HOXA11-AS activates ITGB3 expression to promote the migration and invasion of gastric cancer by sponging miR-124-3p

BACKGROUND

miR-124-3p can inhibit integrin β3 (ITGB3) expression to suppress the migration and invasion of gastric cancer (GC), and in the process lncRNA HOXA11-AS may act as a molecular sponge.

METHODS

Luciferase reporter assay was conducted to verify the binding of miR-124-3p and HOXA11-AS. RT-PCR and western blot were performed to detect the expression of HOXA11-AS, miR-124-3p and ITGB3 in GC tissues and cells. Gene silence and overexpression experiments as well as cell migration and invasion assays on GC cell lines were performed to determine the regulation of molecular pathways, HOXA11-AS/miR-124-3p/ITGB3. Furthermore, the role of HOXA11-AS in GC was confirmed in mice models.

RESULTS

We found HOXA11-AS is up-regulated in GC tissues and can bind with miR-124-3p. Through overexpression/knockdown experiments and function tests in vitro, we demonstrated HOXA11-AS can promote ITGB3 expression by sponging miR-124-3p, consequently enhance the proliferation, migration, and invasion of GC cells. Meanwhile, we validated that HOXA11-AS promotes migration and invasion of GC cells via down-regulating miR-124-3p and up-regulating ITGB3 in vivo.

CONCLUSIONS

We demonstrated that lncRNA HOXA11-AS can increase ITGB3 expression to promote the migration and invasion of gastric cancer by sponging miR-124-3p. Our results suggested that HOXA11-AS may reasonably serve as a promising diagnostic biomarker and a potential therapeutic target of GC.

Long noncoding HOXA11-AS knockdown suppresses the progression of non-small cell lung cancer by regulating miR-3619-5p/SALL4 axis

Accumulating evidence suggested that many long noncoding RNAs (lncRNAs) were widely involved in the development and progression of non-small cell lung cancer (NSCLC). However, the roles of lncRNA homeobox A11 antisense (HOXA11-AS) and its underlying mechanism in NSCLC remains largely unknown. The expression levels of HOXA11-AS, miR-3619-5p and sal-like protein 4 (SALL4) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot analysis was used to measure the protein levels of hexokinase II (HK2) and SALL4. Cell proliferation, apoptosis, migration and invasion were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry and transwell assay, respectively. The glucose consumption and lactate production were measured using glucose assay kit and lactate assay kit, respectively. The potential binding sites between miR-3619-5p and HOXA11-AS or SALL4 were predicted by online software and verified by luciferase report assay. A xenograft tumor model was established to confirm the function of HOXA11-AS in NSCLC in vivo. HOXA11-AS and SALL4 were upregulated while miR-3619-5p was downregulated in NSCLC tissues and cells. HOXA11-AS knockdown suppressed cell proliferation, migration, invasion, and glycolysis but promoted apoptosis in NSCLC cells. Moreover, miR-3619-5p could directly bind to HOXA11-AS and its inhibition attenuated the inhibitory effect of HOXA11-AS knockdown on progression of NSCLC cells. Furthermore, SALL4 was a direct target of miR-3619-5p and its overexpression reversed the anti-tumor role of miR-3619-5p in NSCLC cells. Besides, HOXA11-AS modulated SALL4 expression via sponging miR-3619-5p. Additionally, silencing HOXA11-AS inhibited tumor growth though upregulating miR-3619-5p and downregulating SALL4. Collectively, HOXA11-AS knockdown inhibited the progression of NSCLC by regulating miR-3619-5p/SALL4 axis, which might offer a novel avenue for interpreting the mechanism of NSCLC development.

LncRNA signature in colorectal cancer

Colorectal cancer (CRC) is among the most frequent cancers and is associated with high mortality particularly when being diagnosed in advanced stages. Although several environmental and intrinsic risk factors have been identified, the underlying cause of CRC is not clear in the majority of cases. Several studies especially in the recent decade have pointed to the role of epigenetic factors in this kind of cancer. Long non-coding RNAs (lncRNAs) as important contributors in the epigenetic mechanisms are involved in the initiation, progression and metastasis of CRC. Tens of oncogenic lncRNAs and a lower number of tumor suppressor lncRNAs have been recently identified to be dysregulated in CRC cells and tissues. Notably, expressions of a number of these transcripts have been dysregulated in serum samples of CRC patients, providing a non-invasive route for detection of this kind of cancer. The involvement of lncRNAs in the regulation of autophagy has provided them the ability to modulate response of CRC cells to chemotherapeutic modalities. In the current manuscript, we review the studies which evaluated the role of lncRNAs in the pathogenesis and progression of CRC to appraise their application as diagnostic/ prognostic markers.

Long Noncoding RNA HOXA11-AS Modulates the Resistance of Nasopharyngeal Carcinoma Cells to Cisplatin via miR-454-3p/c-Met

To elucidate the mechanism of action of HOXA11-AS in modulating the cisplatin resistance of nasopharyngeal carcinoma (NPC) cells. HOXA11-AS and miR-454-3p expression in NPC tissue and cisplatin-resistant NPC cells were measured via quantitative reverse transcriptase polymerase chain reaction. NPC parental cells (C666-1 and HNE1) and cisplatin-resistant cells (C666-1/DDP and HNE1/DDP) were transfected and divided into different groups, after which the MTT method was used to determine the inhibitory concentration 50 (IC50) of cells treated with different concentrations of cisplatin. Additionally, a clone formation assay, flow cytometry and Western blotting were used to detect DDP-induced changes. Thereafter, xenograft mouse models were constructed to verify the in vitro results. Obviously elevated HOXA11-AS and reduced miR-454-3p were found in NPC tissue and cisplatin-resistant NPC cells. Compared to the control cells, cells in the si-HOXA11-AS group showed sharp decreases in cell viability and IC50, and these results were reversed in the miR-454-3p inhibitor group. Furthermore, HOXA11-AS targeted miR-454-3p, which further targeted c-Met. In comparison with cells in the control group, HNE1/DDP and C666-1/DDP cells in the si-HOXA11-AS group demonstrated fewer colonies, with an increase in the apoptotic rate, while the expression levels of c-Met, p-Akt/Akt and p-mTOR/mTOR decreased. Moreover, the si-HOXA11-AS-induced enhancement in sensitivity to cisplatin was abolished by miR-454-3p inhibitor transfection. The in vivo experiment showed that DDP in combination with si-HOXA11-AS treatment could inhibit the growth of xenograft tumors. Silencing HOXA11-AS can inhibit the c-Met/AKT/mTOR pathway by specifically upregulating miR-454-3p, thus promoting cell apoptosis and enhancing the sensitivity of cisplatin-resistant NPC cells to cisplatin.

SNP-SNP interactions of oncogenic long non-coding RNAs HOTAIR and HOTTIP on gastric cancer susceptibility

Genetic variants within oncogenic long non-coding RNAs HOTAIR and HOTTIP may affect their gene expression levels, thereby modifying genetic susceptibility to gastric cancer (GC). In a hospital-based study in Ardabil-a very high-risk area in North-West Iran, 600 blood samples from 300 GC patients and 300 healthy controls were recruited for genotyping. Seven HOTAIR (i.e., rs17720428, rs7958904, rs1899663, and rs4759314) and HOTTIP (i.e., rs3807598, rs17501292, and rs1859168) 'tag' single nucleotide polymorphisms (SNPs) were genotyped by the Infinium HTS platform. The rs17720428, rs7958904, and rs1899663 tagSNPs significantly increased GC risk under dominant models by 1.5-, 1.57-, and 1.5-fold, respectively. The G-C-T-A haplotype of HOTAIR tagSNPs increased the risk of GC by 1.31-fold. No significant association was found between HOTTIP SNPs and the risk of GC. HOTAIR and HOTTIP variants were also not associated with any clinicopathologic characteristics. The SNP-SNP interaction of HOTAIR rs17720428/rs7958904 with HOTTIP rs1859168 was associated with an increased risk of GC (rs17720428 TG-rs1859168 CC, OR = 1.76; rs7958904 GC-rs1859168 CC, OR = 1.85; rs7958904 CC-rs1859168 CC, OR = 1.86). Interestingly, the SNP-SNP interaction of HOTAIR rs1899663 with HOTTIP rs1859168 strongly increased the risk of GC (rs1899663 GT-rs1859168 CC, OR = 4.3; rs1899663 TT-rs1859168 CC, OR = 9.37; rs1899663 TT-rs1859168 CA, OR = 6.59). We showed that the HOTAIR rs17720428, rs7958904, and rs1899663 tagSNPs and their interactions with the HOTTIP rs1859168 polymorphism significantly increased the risk of GC. Specifically, novel SNP-SNP interactions between HOTAIR and HOTTIP tagSNPs have a larger impact than individual SNP effects on GC risk, thereby providing us with valuable information to reveal potential biological mechanisms for developing GC.

The long non-coding RNA HOXA11-AS promotes epithelial mesenchymal transition by sponging miR-149-3p in Colorectal Cancer

Background: Metastasis is the primary cause of death in colorectal cancer (CRC); the underlying mechanisms remain partly unknown. In this study, we aim to investigate the value of HOXA11-AS in survival evaluation and the potential role of HOXA11-AS/miR-149-3p axis in the CRC metastasis.

Methods: The expressions of HOXA11-AS, both in obtained CRC samples and adjacent noncancerous tissues, were analyzed in survival evaluation. Competing endogenous RNAs (CeRNAs) Analysis were employed to reveal the potential relationship between HOXA11-AS and miR-149-3p. It was further confirmed by Quantitative real-time polymerase chain reaction (qRT-PCR) and Dual-luciferase reporter assay. Migration and invasion assay were used to verify the potential role of HOXA11-AS and miR-149-3p in the regulation of CRC metastasis. The potential pathway was explored by Western blot analysis.

Results: The expression of HOXA11-AS in the CRC tissue is significantly higher than the expression in adjacent noncancerous tissue (p<0.0001). High expressions of HOXA11-AS were noticeably correlated with clinicopathologic characteristics including advanced clinical stage (p=0.021), larger tumor size (p<0.001) and frequent tumor recurrence (p=0.001). The overall survival in HOXA11-AS-High group was significantly shorter than the HOXA11-AS-Low group (p<0.001). Advanced clinical stage, tumor size and high expression of HOXA11-AS were showed as independent prognostic prediction factors for the 5-year tumor relapse of CRC patients (p<0.001). HOXA11-AS acts as a potential molecular sponge for miR-149-3p, in the promotion of CRC metastasis. In the miR-149-3p mimic-treated group, the expression of E-cadherin was increased, whereas the expression of N-cadherin, Snail, Slug, TGF-β1, Wnt2b, Twist and C/EBPβ was decreased.

Conclusion: This study demonstrates that high expression of HOXA11-AS is correlated with CRC progression and poor prognosis and may promote metastasis via EMT by modulating miR-149-3p.

Recent advances in unraveling the molecular mechanisms and functions of HOXA11‑AS in human cancers and other diseases (Review)

A large number of previously published research articles have demonstrated that the expression levels of long noncoding RNAs (lncRNAs) are generally dysregulated, either through overexpression or underexpression, in cancer and other types of disease. As a recently discovered lncRNA, HOXA11 antisense RNA (HOXA11‑AS) is able to serve as an oncogenic or tumor‑suppressor gene and serves a vital role in the processes of proliferation, invasion, and migration of cancer cells. HOXA11‑AS appears to be a major factor contributing to epigenetic modification, and exerts transcriptional, post‑transcriptional, translational and post‑translational regulatory effects on genes through a variety of mechanisms; for example, by competing endogenous RNA (ceRNA) and a molecular scaffold mechanism. A number of reports have demonstrated that HOXA11‑AS functions as a protein scaffold for polycomb repressive complex 2 (PRC2), lysine‑specific histone demethylase 1 (LSD1) and DNA methyltransferase 1 (DNMT1) to perform epigenetic modifications on chromosomes in the nucleus. Furthermore, HOXA11‑AS is also located in the cytoplasm and can act as a ceRNA, which sponges miRNAs. In addition, HOXA11‑AS may be useful as a biomarker for the diagnosis and prognosis of cancer. In the present review article, the clinical value, phenotype and mechanism of HOXA11‑AS in a variety of tumors types are briefly summarized, as well as its clinical value in certain additional diseases. The perspective of the authors is that HOXA11‑AS may represent an effective tumor marker and therapeutic target for cancer diagnosis and therapy.

Transcriptome Analysis Identifies LINC00152 as a Biomarker of Early Relapse and Mortality in Acute Lymphoblastic Leukemia

Evidence showing the role of long non-coding RNAs (lncRNAs) in leukemogenesis have emerged in the last decade. It has been proposed that these genes can be used as diagnosis and/or prognosis biomarkers in childhood acute lymphoblastic leukemia (ALL). To know if lncRNAs are associated with early relapse and early mortality, a microarray-based gene expression analysis in children with B-lineage ALL (B-ALL) was conducted. Cox regression analyses were performed. Hazard ratios (HR) and 95% confidence intervals (95% CI) were calculated. LINC00152 and LINC01013 were among the most differentially expressed genes in patients with early relapse and early mortality. For LINC00152 high expression, the risks of relapse and death were HR: 4.16 (95% CI: 1.46–11.86) and HR: 1.99 (95% CI: 0.66–6.02), respectively; for LINC01013 low expression, the risks of relapse and death were HR: 3.03 (95% CI: 1.14–8.05) and HR: 6.87 (95% CI: 1.50–31.48), respectively. These results were adjusted by NCI risk criteria and chemotherapy regimen. The lncRNA–mRNA co-expression analysis showed that LINC00152 potentially regulates genes involved in cell substrate adhesion and peptidyl–tyrosine autophosphorylation biological processes. The results of the present study point out that LINC00152 could be a potential biomarker of relapse in children with B-ALL.

Antisense lncRNA LDLRAD4-AS1 promotes metastasis by decreasing the expression of LDLRAD4 and predicts a poor prognosis in colorectal cancer

Long noncoding RNAs (lncRNAs) have been revealed to play critical roles in tumor initiation and progression. The antisense lncRNA LDLRAD4-AS1 is the longest lncRNA of LDLRAD4, and its expression levels, cellular localization, precise function, and mechanism in colorectal cancer (CRC) remain unknown. In this study, we observed that lncRNA LDLRAD4-AS1 was located in the nucleus of CRC cells and that lncRNA LDLRAD4-AS1 was upregulated in most CRC specimens and cell lines. Overexpression of lncRNA LDLRAD4-AS1 was correlated with poor prognosis in CRC patients. LncRNA LDLRAD4-AS1 upregulation enhanced the migration and invasion of CRC cells in vitro and facilitated CRC metastasis in vivo. Mechanistic investigations suggested that lncRNA LDLRAD4-AS1 could decrease the expression of LDLRAD4 by disrupting the stability of LDLRAD4 mRNA, resulting in epithelial-to-mesenchymal transition (EMT) through upregulating Snail, thereby promoting metastasis in CRC. Our results demonstrated a previously unrecognized LDLRAD4-AS1-LDLRAD4-Snail regulatory axis involved in epigenetic and posttranscriptional regulation that contributes to CRC progression and metastasis.

The Polymorphisms of lncRNA HOXA11-AS and the risk of Lung Cancer in Northeastern Chinese population

Long non-coding RNAs (LncRNA) have been wildly explored in several malignant tumors. This study aimed to evaluate the effect of HOXA11-AS polymorphisms (rs17427875 and rs11564004) on lung cancer susceptibility and its interaction with smoking exposure. This hospital-based case-control study, which included 466 cases and 557 controls, was carried out in Shenyang City, Liaoning province. The genotyping method was TaqMan allelic discrimination assay and all statistical analysis were performed by SPSS 20.0 and R (3.5.3). The results demonstrated that HOXA11AS-rs17427875 polymorphisms were correlated with the susceptibility of lung adenocarcinoma. T alleles of rs17427875 played a portal role in increasing lung adenocarcinoma risk. HOXA11AS-rs11564004 polymorphisms had the significant association with lung cancer risks, as well as its subtypes like non-small cell lung cancer, adenocarcinoma. The allele G of rs11564004 acted as a protective factor for lung cancer. The similar results were observed in the homozygous model and recessive model of rs11564004. Nevertheless, interaction analysis of the additive and multiplicative model scales showed no statistical significance between HOXA11-AS polymorphisms and smoking exposure in the development of lung cancer.

Long non-coding RNA HOXA11-AS accelerates the progression of keloid formation via miR-124-3p/TGFβR1 axis

Emerging evidence reveals the importance of long non-coding RNAs (lncRNAs) in the development and progression of keloid formation, whereas the underlying mechanisms are not well understood. In the present study, we investigated the biological effects and molecular mechanisms of lncRNA HOXA11-AS in keloid formation. First, the expression levels of HOXA11-AS, miR-124-3p, and transforming growth factor β receptor type I (TGFβR1) were measured in both keloid tissues and human keloid fibroblasts (HKFs) using qRT-PCR and western blot analysis, respectively. Next, we adopted both gain- and loss-of-function strategies to explore the significance of HOXA11-AS. TUNEL, flow cytometry, DNA ladder, and tube formation assays were performed to measure cell apoptosis and angiogenesis, respectively. Besides, the potential binding relationship between HOXA11-AS and miR-124-3p, as well as miR-124-3p and TGFβR1 was identified using bioinformatic screening and verified by luciferase reporter assay. Furthermore, we explored the importance of miR-124-3p in HOXA11-AS-induced phenotypes and regulations on TGFβ signaling or PI3K/Akt signaling. We found that HOXA11-AS and TGFβR1 were significantly up-regulated, while miR-124-3p was down-regulated both in keloid tissues or fibroblasts than in normal skin tissues or fibroblasts. Functionally, high expression of HOXA11-AS essentially inhibited cell apoptosis and promoted fibroblast-induced angiogenesis. Mechanistically, miR-124-3p was identified as a downstream effector to be involved in HOXA11-AS-mediated phenotypes through directly targeting TGFβR1, thus modulating PI3K/Akt signaling pathway. Taken together, our findings revealed that HOXA11-AS inhibits cell apoptosis and promotes angiogenesis through miR-124-3p/TGFβR1 axis, contributing to the progression of keloid formation, which might provide a novel target for keloid therapy.

Long Non-Coding RNA HOXA11-AS Promotes Non-Small Cell Lung Cancer Tumorigenesis Through microRNA-148a-3p/DNMT1 Regulatory Axis

OBJECTIVE

Our present study aimed to further investigate the molecular basis of long non-coding RNA homeobox A11 antisense (HOXA11-AS) in the tumorigenesis of non-small cell lung cancer (NSCLC).

METHODS

HOXA11-AS, microRNA-148a-3p (miR-148a-3p), and DNA methyltransferase 1 (DNMT1) mRNA levels were measured by RT-qPCR assay. DNMT1 protein level was determined by Western blot assay. Cell proliferative capacity and apoptotic rate were determined by CCK-8 assay and flow cytometry analysis, respectively. The relationships of HOXA11-AS, miR-148a-3p, and DNMT1 were tested through bioinformatics analysis, luciferase assay, and RNA pull down assay. Mouse xenograft models of NSCLC were established to examine the biological function of HOXA11-AS in vivo.

RESULTS

HOXA11-AS expression was notably upregulated and miR-148a-3p expression was conspicuously downregulated in NSCLC tissues and cells. HOXA11-AS knockdown curbed NSCLC cell proliferation and promoted cell apoptosis through directly increasing miR-148a-3p expression. Moreover, miR-148a-3p overexpression suppressed NSCLC cell proliferation and induced cell apoptosis. HOXA11-AS functioned as a competing endogenous RNA (ceRNA) of miR-148a-3p to increase DNMT1 expression in NSCLC cells. And, DNMT1 upregulation weakened the influence of HOXA11-AS1 loss on NSCLC cell proliferation and apoptosis. Additionally, HOXA11-AS knockdown suppressed NSCLC xenograft growth by upregulating miR-148a-3p and downregulating DNMT1 in vivo.

CONCLUSION

HOXA11-AS facilitated NSCLC tumorigenesis through miR-148a-3p/DNMT1 axis in vitro and in vivo, deepening our understanding of the molecular basis of HOXA11-AS in the development of NSCLC.

Silencing of lncRNA HOXA11-AS inhibits cell migration, invasion, proliferation, and promotes apoptosis in human glioma cells via upregulating microRNA-125a: in vitro and in vivo studies

Glioma is an aggressive nervous system tumor with poor prognosis. Although the therapeutic strategies to overcome glioma have been improved largely recent years, the potential mechanism of its carcinogenesis remains largely unclear. The present study aimed to investigate the role of long non-coding RNA HOMEOBOX A11 antisense RNA (lncRNA HOXA11-AS) in glioma, and further to explore the underlying mechanism. We forst detected the level of lncRNA HOXA11-AS and microRNA-125a (miR-125a) in glioma tissues and human glioma U251 cells using quantitative real time polymerase chain reaction (qRT-PCR). Then, effect of lncRNA HOXA11-AS silencing on U251 cell migration, invasion, proliferation, and apoptosis was determined. Meanwhile, the expression of caspase-3/8/9 and several tumor-related genes was measured by Western blotting and qRT-PCR. Dual luciferase activity assay was used to confirm the targeting relationship between lncRNA HOXA11-AS and miR-125a. Results indicated that lncRNA HOXA11-AS was significantly increased in U251 cells and positively correlated with glioma World Health Organization (WHO) grade in glioma tissues. lncRNA HOXA11-AS silencing could inhibit cell migration, invasion, proliferation, and promote apoptosis, while up-regulate the expression of caspase-3/8/9 and Bax, inhibit the expression of Bcl-2 and gab2 in U251 cells. miR-125a inhibitor could partially reverse these effects of lncRNA HOXA11-AS silencing on U251 cells. In vivo assays also indicated that lncRNA HOXA11-AS inhibitor could inhibit glioma growth in vivo by regulating the expression of miR-125a. In conclusion, we revealed that lncRNA HOXA11-AS acted as an oncogene in glioma via interacting with miR-125a and considered that lncRNA HOXA11-AS was a potential therapeutic target for glioma.

The Intricate Interplay between Epigenetic Events, Alternative Splicing and Noncoding RNA Deregulation in Colorectal Cancer

Colorectal cancer (CRC) results from a transformation of colonic epithelial cells into adenocarcinoma cells due to genetic and epigenetic instabilities, alongside remodelling of the surrounding stromal tumour microenvironment. Epithelial-specific epigenetic variations escorting this process include chromatin remodelling, histone modifications and aberrant DNA methylation, which influence gene expression, alternative splicing and function of non-coding RNA. In this review, we first highlight epigenetic modulators, modifiers and mediators in CRC, then we elaborate on causes and consequences of epigenetic alterations in CRC pathogenesis alongside an appraisal of the complex feedback mechanisms realized through alternative splicing and non-coding RNA regulation. An emphasis in our review is put on how this intricate network of epigenetic and post-transcriptional gene regulation evolves during the initiation, progression and metastasis formation in CRC.

Long non-coding RNA homeobox A11 antisense RNA (HOXA11-AS) promotes retinoblastoma progression via sponging miR-506-3p

Background: Long non-coding RNA homeobox A11 antisense RNA (HOXA11-AS) has been reported to be involved in initiation and development of multiple cancers. However, the detailed biological roles and underlying molecular mechanism of HOXA11-AS remain unclear in retinoblastoma (RB). Herein, the goals of this study were to explore the biological function and the potential mechanism of HOXA11-AS in RB.

Materials and methods: The expression of HOXA11-AS in RB tissues and cell lines was detected using real-time PCR (qRT-PCR). Cell proliferation, cycle arrest and apoptosis were measured using a cell counting kit 8 and flow cytometry. The target miRNAs of HOXA11-AS was predicted by Starbase2.0 software and was confirmed using a dual-luciferase reporter assay.

Result: We found that HOXA11-AS expression was markedly elevated in RB tissues and cell lines compared to normal retina tissues and human retinal epithelial cells, respectively. Functional analysis showed that knockdown of HOXA11-AS in RB cells significantly suppressed cell proliferation, and induced cell cycle arrest at G1/G0 phase and promoted cell apoptosis. We also found that HOXA11-AS could serve as a competing endogenous RNA (ceRNA) that inhibited miR-506-3p expression, which regulated its downstream target NIMA-related kinase 6 (NEK6) in RB. In addition, miR-506-3p inhibitors partially reversed the effect of HOXA11-AS depletion on proliferation, cycle arrest and apoptosis in RB cells.

Conclusion: Taken together, these findings demonstrated that HOXA11-AS could promote RB progression by sponging miR-506-3p, suggesting that HOXA-11-AS might be a potential therapeutic target for RB.

Identification of a 26-lncRNAs Risk Model for Predicting Overall Survival of Cervical Squamous Cell Carcinoma Based on Integrated Bioinformatics Analysis

As a common malignancy in women, cervical squamous cell carcinoma is a major cause of cancer-related mortality globally. Recent studies have demonstrated that long non-coding RNA (lncRNA) can function as potential biomarkers in cancer prognosis; however, little is known about its role in cervical cancer. In this study, we downloaded the gene expression profiles along with the clinical data of patients with cervical squamous cell carcinoma from The Cancer Genome Atlas. By applying bioinformatics analysis including random forest selection and Least Absolute Shrinkage and Selection Operator (LASSO) cox regression model along with 10-fold cross-validation, we constructed a 26-lncRNAs risk model that can be used to predict the overall survival of cervical squamous cell carcinoma. After that, Kaplan-Meier analysis combined with log-rank p test was applied to assess the predictive accuracy of the 26-lncRNAs risk model. Further analysis showed that the prognostic value of 26-lncRNAs risk model was independent of other clinicopathological factors. At last, lncRNAs in the model were put into gene ontology biological process enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways analysis, which suggested that these lncRNAs might contribute to cancer-associated processes such as cell cycle and apoptosis. This study indicated that lncRNAs signature could be a useful marker to predict the prognosis of cervical squamous cell carcinoma.

Long non-coding RNA POLR2E gene polymorphisms increased the risk of prostate cancer in a sample of the Iranian population

The current study aimed to examine the impact of POLR2E rs1046040 and rs3787016 polymorphisms on prostate cancer (PCa) risk in a sample of southeast Iranian population. The present case-control study was performed on 178 patients with PCa and 180 benign prostatic hyperplasia (BPH). Genotyping of the variants was done by mismatch PCR-RFLP. The findings showed that the rs3787016 C > T variant significantly increased the risk of PCa in codominant (OR = 1.84, 95% CI = 1.12-3.03, P = 0.018, CT vs CC), dominant (OR = 1.88, 95% CI = 1.63-3.05, P = 0.011, CT + TT vas CC) and allele (OR = 1.77, 95% CI = 1.52-2.72, P = 0.010, T vs C) inheritance model. Regarding rs1046040 C > T polymorphism, the findings revealed that the CT genotype significantly increased the risk of PCa compared to the CC genotype (OR = 1.60, 95% CI = 1.03-2.49, P = 0.043). Furthermore, rs3787016 CT/rs1046040 CC as well as rs3787016 CT/rs1046040 CT increased the risk of PCa compared to the CC/CC genotype (p = 0.029 and p = 0.014, respectively). Haplotype analysis proposed that rs3787016 T/rs1046040 C significantly increased the risk of PCa compared to C/C (p = 0.037). No significant association was observed between POLR2E variants and clinicopathological characteristics of PCa patients. In conclusion, the findings propose that POLR2E variants may be a risk factor for susceptibility to PCa in a sample of Iranian population.

Role of lncRNA and EZH2 Interaction/Regulatory Network in Lung Cancer

Lung cancer is the leading cause of cancer-related deaths worldwide. Long non-coding RNAs (lncRNAs) are non-protein-coding transcripts and longer than 200 nucleotides. LncRNAs have been demonstrated to modulate gene expression at transcriptional, post-transcriptional, as well as epigenetic levels in lung cancer. Interestingly, compelling studies have revealed that lncRNAs participated in the EZH2 oncogenic regulatory network. EZH2 plays an important role in the initiation, progression and metastasis of cancer. On one hand, lncRNAs can directly bind to EZH2, recruit EZH2 to the promoter region of genes and repress their expression. On the other hand, lncRNAs can also serve as EZH2 effectors or regulators. In this review, we summarized the types of lncRNA-EZH2 interaction and regulatory network identified till date and discussed their influence on lung cancer. Better understanding regarding the interaction and regulatory network will provide new insights on lncRNA- or EZH2-based therapeutic development in lung cancer.

Long non-coding RNA LINC01410 promotes colon cancer cell proliferation and invasion by inhibiting miR-3128

A previous study implied that long intergenic non-coding RNA 1410 (LINC01410) promotes angiogenesis and metastasis of gastric cancer. However, the role of LINC01410 in colon cancer (CC) has remained elusive. In the present study, LINC01410 was identified to be highly expressed in CC tissues compared to adjacent normal tissues. It was indicated that high expression of LINC01410 in CC tissues was associated with poor prognosis. Further functional study suggested that LINC01410 knockdown significantly reduced the proliferation and invasive capacity of HT-29 and SW620 cells, and inhibited the cell cycle. Regarding the mechanism, LINC01410 was indicated to serve as a sponge for microRNA (miR)-3128, as evidenced by a luciferase reporter assay. Furthermore, knockdown of LINC01410 significantly increased the levels of miR-3128. In addition, miR-3128 was markedly downregulated in CC tissues compared with that in adjacent normal tissues. A rescue assay revealed that inhibition of miR-3128 significantly abrogated the effects of LINC01410 knockdown on CC cell proliferation and invasion. In conclusion, the present study demonstrated that LINC01410 functions as an oncogene in CC, at least in part by directly inhibiting miR-3128.

The role of the long non-coding RNA HOXA11-AS in promoting proliferation and metastasis of malignant tumors

Long non-coding RNA (lncRNA) is one of the focuses and hotspots of biological research in recent years. At the same time, tumors have become the main disease that endangers human health. In recent years, a large number of researchers have explored the relationship between lncRNA and tumors. HOXA11-AS is one of these lncRNAs. The long non-coding RNA HOXA11 antisense RNA (HOXA11-AS) is a novel lncRNA recently discovered. It is found in a variety of tumors such as ovarian cancer, glioma, and gastric cancer (GC) and so on, and is defined as an oncogene. It promotes tumor proliferation and metastasis by interacting with proteins such as miRNA and EZH2. In this paper, we review the mechanism of interaction between HOXA11-AS and various tumors in recent years, and believe that it can be a potential tumor marker and therapeutic target in the future prevention and treatment of tumors.

HOXA11-AS: a novel regulator in human cancer proliferation and metastasis

Multiple studies have demonstrated that lncRNAs extensively participate in human cancer proliferation and metastasis. Epigenetic modification, transcriptional and posttranscriptional regulatory mechanisms are involved in lncRNA-led tumorigenesis and transfer. Recently, a novel identified homeobox (HOX) A11 antisense lncRNA, HOXA11-AS, 1,628 bp in length, has been excessively highlighted to be an essential initiator and facilitator in the process of malignant tumor proliferation and metastasis. As found in many reports, HOXA11-AS can not only act as a molecular scaffold of PRC2, LSD1 and DNMT1 to epigenetically modify chromosomes in the nucleus but also occur as ceRNA competitively sponging miRNAs in the cytoplasm. Furthermore, HOXA11-AS may function as a potential biomarker for cancer diagnosis and prognosis. In this review, we summarize the evolvement and mechanisms of HOXA11-AS in proliferation and metastasis of various human cancers.

HOXA11 antisense long noncoding RNA (HOXA11-AS): A promising lncRNA in human cancers

The cancers are the leading cause of disease‐related deaths worldwide with a high risk of morbidity and mortality. Long noncoding RNAs (lncRNAs) play a critical role in a wide range of biological processes, including tumorigenesis. HOXA11‐AS (NCRNA00076), the antisense strands of HOXA11 gene, was initially revealed in a mouse embryonic cDNA library in 2009 and it was a fairly novel lncRNA. This review summarized the advanced research progression concerning the expression and role of HOXA11‐AS in different human malignancies. The expression of HOXA11‐AS is aberrantly altered in many cancers, either as a tumor suppressor or as a tumor accelerator. The different underlying mechanism of HOXA11‐AS in different cancers (including, nonsmall cell lung cancers, osteosarcoma, uveal melanoma, glioma, hepatocellular carcinoma, gastric cancer, breast cancer, cervical cancer, ovarian cancer, colorectal cancer, ovarian cancer, and glioblastoma) was also detailed. These findings lead us to conclude that HOXA11‐AS participate in the complex network of cancers and plays an important role in the tumorigenesis and progression. Functional HOXA11‐AS could be a promising biomarker for early detection as well as prognosis evaluation in cancer patients. Future HOXA11‐AS‐targeted intervention may become a valuable novel therapeutic tool, improving the clinical management of cancers.

Epigenetic regulation of long non-coding RNAs in gastric cancer

Gastric cancer is one of the most common cancers and is the second leading cause of cancer mortality worldwide. Therefore, it is urgent to explore new molecular biomarkers for early diagnosis, early treatment and prognosis for gastric cancer patients. Recently, increasing evidence has shown that epigenetic changes, such as aberrant DNA methylation, histone modifications, and noncoding RNAs (ncRNAs) expression, play substantial roles in the development and progression of malignancies. Among these changes, long non-coding RNAs (lncRNAs), a novel class of ncRNAs, are emerging as highly versatile actors in a variety of cellular processes by regulating gene expression at the epigenetic level as well as at the transcriptional and post-transcriptional levels. Hundreds of lncRNAs become dysregulated in the various pathological processes of gastric cancer, and multiple lncRNAs have been reported to function as tumor-suppressors or oncogenes, although the underlying mechanisms are still under investigation. Here, we provide an overview of the epigenetic regulation of chromatin and the molecular functions of lncRNAs; we focus on lncRNA-mediated epigenetic regulation of cancer-related gene expression in gastric cancer, as well as discuss the clinical implications of lncRNAs on epigenetic-related cancer treatments, which may contribute helpful approaches for the development of new potential strategies for future diagnosis and therapeutic intervention in human cancers.

Long noncoding RNA LINC01510 promotes the growth of colorectal cancer cells by modulating MET expression

Background

Abnormal expression of long non-coding RNA (lncRNAs) often facilitates unrestricted growth of cancer cells. Long intergenic non-protein coding RNA 1510, an enhancer lncRNA (LINC01510), a lncRNA enhancer is upregulated in colorectal cancer (CRC), and its expression might relate to MET as revealed by lncRNA microarray data. However, the potential biological role of LINC01510 and its regulatory mechanism in CRC remain unclear. Therefore, we investigated the involvement of LINC01510 in the proliferation of CRC cells.

Methods

Microarray analysis, In situ hybridization, colony formation assay, MTT assay, Western blotting, quantitative RT-PCR and flow cytometry were applied. The two-tailed Student’s t test and analysis of variance or general linear model of single factor variable was used for statistical analyse.

Results

In the present study, we found that LINC01510 was significantly upregulated in CRC tissues and cell lines. The LINC01510 expression level were associated with the clinicopathological grade and stage. Meanwhile, gain- and loss-of-function assays demonstrated that LINC01510 overexpression increased CRC cell proliferation, and promoted cell cycle progression from the G1 phase to the S phase. Further study indicated that LINC01510 was positively correlated with the expression of MET, and its effects were most likely at the transcriptional level.

Conclusions

Taken together, our findings suggested that upregulation of LINC01510 contributes to the proliferation of CRC cells, at least in part, through the regulation of MET protein. LINC01510 could be a candidate prognostic biomarker and a target for new therapies in CRC patients.

lncRNA FEZF1-AS1 Is Associated With Prognosis in Lung Adenocarcinoma and Promotes Cell Proliferation, Migration, and Invasion

Long noncoding RNAs (lncRNAs) have been reported to play important roles in tumorigenesis. In the present study, we demonstrated that lncRNA forebrain embryonic zinc finger protein 1 (FEZF1) antisense RNA1 (FEZF1-AS1) is markedly upregulated in human lung adenocarcinoma (LAD) tissues and cell lines and is associated with poor prognosis. Loss of function revealed that deletion of FEZF1-AS1 expression significantly inhibited the LAD cell proliferation, invasion, and migration. Further studies revealed that downregulation of FEZF1-AS1 reduced mRNA and protein expression of its sense-cognate gene FEZF1 in LAD cells, and vice versa. Correlation analysis indicated that there was a positive correlation between FEZF1-AS1 and FEZF1 expression in LAD tissues. Additionally, rescue assay confirmed that the function of FEZF1-AS1 in LAD was mediated by FEZF1. Our findings suggested that dysregulation of FEZF1-AS1 contributed to the progression of LAD, which might be a potential target for LAD therapy.

Alteration of Epigenetic Regulation by Long Noncoding RNAs in Cancer

Long noncoding RNAs (lncRNAs) are important regulators of the epigenetic status of the human genome. Besides their participation to normal physiology, lncRNA expression and function have been already associated to many diseases, including cancer. By interacting with epigenetic regulators and by controlling chromatin topology, their misregulation may result in an aberrant regulation of gene expression that may contribute to tumorigenesis. Here, we review the functional role and mechanisms of action of lncRNAs implicated in the aberrant epigenetic regulation that has characterized cancer development and progression.

Long non-coding RNA HOXA11-AS promotes the proliferation HCC cells by epigenetically silencing DUSP5

Hepatocellular carcinoma has been identified as the fifth most common cancer in men and the ninth in women worldwide. Despite many efforts have been made in recent years, the overall survival rate of patients with hepatocellular carcinoma still remain unsatisfied. Therefore, exploring the mechanisms underlying the progression of hepatocellular carcinoma is essential for developing novel treatments to improve patient prognosis. HOXA11-AS, transcribed from the opposite strand of the protein-coding gene HOXA11, has been identified to be associated with the malignant characteristics of several cancers. However, the biological role and molecular mechanism of HOXA11-AS in hepatocellular carcinoma still need to be further investigated. In the current study, the expression of HOXA11-AS in the hepatocellular carcinoma cell lines and tissues was measured by quantitative real-time PCR. Loss-of-function and gain-of-function approaches were applied to investigate the proliferative function of HOXA11-AS in hepatocellular carcinoma cells. Results from flow cytometric analysis of apoptosis and cell cycle distribution revealed that HOXA11-AS promoted hepatocellular carcinoma cells proliferation through regulating cell cycle and apoptosis. Gene chip technology and quantitative real-time PCR confirmed that DUSP5 was a downstream target of HOXA11-AS. RNA immune co-precipitation assays, RNA pull-down and Chromatin immunoprecipitation assays confirmed that HOXA11-AS could recruit EZH2 to the promoter region of DUSP5, which therefore suppressed the transcription of DUSP5. Collectively, these findings revealed that HOXA11-AS functions as an oncogene in hepatocellular carcinoma through interacting with polycomb-repressive complex2.

LncRNA HOXA11-AS promotes proliferation and invasion by targeting miR-124 in human non-small cell lung cancer cells

Long non-coding RNAs have been implicated in human cancer but their mechanisms of action are mainly undocumented. In this study, we found that HOXA11-AS expression was upregulated in non-small cell lung cancer tissues and cell lines. High levels of HOXA11-AS expression were correlated with larger tumor size and lymph node metastasis. Functional analysis revealed that HOXA11-AS promotes non-small cell lung cancer cell proliferation and invasion. In particular, HOXA11-AS functions as a competing endogenous RNA to regulate transcriptional factor Sp1 expression via sponging miR-124. Collectively, our findings reveal an oncogenic role for HOXA11-AS in non-small cell lung cancer tumorigenesis.

Association between genetic polymorphisms of long non-coding RNA PRNCR1 and prostate cancer risk in a sample of the Iranian population

The aim of the present study was to determine whether there is an association between the long non-coding RNA (lncRNA) prostate cancer-associated non-coding RNA 1 (PRNCR1) polymorphisms and prostate cancer (PCa) risk in a sample of the Iranian population. This case-control study was performed on 178 patients with PCa and 180 subjects with benign prostatic hyperplasia (BPH). Genotyping assay was performed by polymerase chain reaction-restriction fragment length polymorphism. The findings indicated that the GG genotype of the rs13252298 A>G variant significantly increased the risk of PCa (odds ratio=3.49, 95% confidence interval: 1.79-6.81, P=0.0001) compared with AA+AG. As regards the rs1456315 G>A polymorphism, the AG genotype and G allele significantly increased the risk of PCa. As regards the rs7841060 T>G variant, the findings demonstrated that this TG genotype and the G allele significantly increased the risk of PCa. The rs7007694 T>C variant was not found to be associated with the risk of PCa. Haplotype analysis indicated that GTGA and GTGG significantly increased the risk of PCa compared with rs1456315A/rs7007694T/rs7841060T/rs13252298G (ATTG). The PRNCR1 variants were not found to be significantly associated with the clinicopathological characteristics of PCa patients. In conclusion, our findings support an association between PRNCR1 variants and the risk of PCa in a sample of the Iranian population.

Long non-coding RNA HOXA11-AS in human cancer: A meta-analysis

BACKGROUND

Homeobox A11 antisense (HOXA11-AS), a newly identified lncRNA, is up-regulated in various carcinomas. We conducted the present meta-analysis to explore the potential of HOXA11-AS as a common predictive biomarker for metastasis and prognosis in malignant tumors.

METHODS

A systematic literature search on the online electronic databases of PubMed, Web of Science, and Embase was carried out to determine relevant studies (as of July 9, 2017). The pooled hazard ratios (HRs)/odds rates (ORs), and their 95% confidence intervals (CIs) were used to evaluate the relationship.

RESULTS

A total of 608 patients from seven studies were included in the current meta-analysis. The pooled results indicated that high HOXA11-AS expression was related to poor overall survival (OS) (HR=2.02, 95% CI: 1.48-2.75, P<0.001) and progression-free survival (PFS) (HR=1.91, 95% CI: 1.15-3.17, P=0.012). Further analyses reveal that patients with high HOXA11-AS expression are prone to develop distant metastasis (DM) (OR=6.05, 95% CI: 1.66-22.06, P=0.006).

CONCLUSIONS

This meta-analysis showed that increased expression of HOXA11-AS is a risk factor for poor clinical outcomes in numerous tumors and may act as a novel biomarker for poor prognosis and metastasis in cancers.

The lncRNA HOXA11-AS functions as a competing endogenous RNA to regulate PADI2 expression by sponging miR-125a-5p in liver metastasis of colorectal cancer

Several long non-coding RNAs (lncRNAs) play important roles in the regulation of liver metastasis in colorectal cancer (CRC) patients. We previously described the potential involvement of HOMEOBOX A11 (HOXA11) antisense RNA (HOXA11-AS), miR-125a-5p, and peptidyl arginine deiminase 2 (PADI2) in promoting liver metastasis in CRC patients. In the present study, we verified the significant upregulation of HOXA11-AS and PADI2, as well as the downregulation of miR-125a-5p, in CRC patients with liver metastasis. Overexpression and knockdown studies of HOXA11-AS or PADI2, as well as gain-/loss-of-function studies of miR-125a-5p, revealed a positive correlation between HOXA11-AS and PADI2 and a negative correlation with miR-125a-5p in the regulation of liver metastasis in CRC cell lines. Overall, we conclude that HOXA11-AS promotes liver metastasis in CRC by functioning as a miR-125a-5p sponge and describe a novel HOXA11-AS–miR-125a-5p–PADI2 regulatory network involved in CRC liver metastasis.

Clinical Significance and Effect of lncRNA HOXA11-AS in NSCLC: A Study Based on Bioinformatics, In Vitro and in Vivo Verification

HOXA11 antisense RNA (HOXA11-AS) has been shown to be involved in tumorigenesis and development of different cancers. However, the role of HOXA11-AS in non-small cell lung cancer (NSCLC) remains unclear. In this study, we firstly explored and confirmed the expression of HOXA11-AS in NSCLC tissues and cells. Cytometry, CCK-8, cell scratch, migration, Matrigel invasion and flow cytometry assays were performed to determine the biological impact of HOXA11-AS in vitro. Furthermore, a chick embryo chorioallantoic membrane (CAM) model of NSCLC was constructed to explore the effect of HOXA11-AS on tumorigenicity and angiogenesis in vivo. Additionally, bioinformatics analyses were performed to investigate the prospective pathways of HOXA11-AS co-expressed genes. As results, HOXA11-AS was markedly highly expressed in NSCLC tissues and cells. Furthermore, the proliferation, migration, invasion, tumorigenic and angiogenic ability of NSCLC cells were all inhibited and apoptosis was induced after HOXA11-AS knock-down. HOXA11-AS RNAi also led to cell cycle arrest on G0/G1 or G2/M phase. In addition, the non-small cell lung cancer pathway might be involved in regulating the co-expressed genes of HOXA11-AS in NSCLC. These results indicate that HOXA11-AS plays pivotal roles in NSCLC and it can become a novel therapeutic direction for treating NSCLC.

Long Non-Coding RNA (LncRNA) HOXA11-AS Promotes Breast Cancer Invasion and Metastasis by Regulating Epithelial-Mesenchymal Transition

BACKGROUND To detect the expression of lncRNA HOXA11-AS and its biological effect in breast cancer. MATERIAL AND METHODS In this study, fluorescent quantitative real-time PCR (qRT-PCR), MTT assay and clone formation assay, flow cytometry, Transwell assay and wound healing assay, immunofluorescence, and Western blot analysis were conducted to detect the expression of lncRNA HOXA11-AS, cell proliferation activity, cell apoptosis rate and cell cycle distribution, the changes of cell invasion and metastasis capacity, and the expressions of molecular markers of epithelial-mesenchymal transition (EMT), respectively. Additionally, a nude mouse metastatic tumor model was established to study the influence of lncRNA HOXA11-AS on invasion and metastasis capacity of breast cancer cells. RESULTS The qRT-PCR experiment results showed that HOXA11-AS expression in breast cancer tissue of 50 patients was relatively higher than that in tissue adjacent to cancer. MTT assay suggested that tumor cell proliferation capacity was suppressed followed by the knockdown of lncRNA HOXA11-AS expression in MDA-MB-231 and MCF-7 cells; flow cytometry results demonstrated that interfering in lncRNA HOXA11-AS could induce tumor cell apoptosis and promote cell cycle progression to be arrested in G1/G0 stage; experiments in vivo/vitro manifested that interfering in lncRNA HOXA11-AS could inhibit tumor cell invasion and migration capacity by affecting the expressions of EMT-related molecular markers (E-cadherin, N-cadherin, Vimentin). CONCLUSIONS High expression of lncRNA HOXA11-AS promotes breast cancer invasion and metastasis by affecting EMT, and interfering in lncRAN HOXA11-AS expression provides a theoretical basis and important molecular target for inhibiting the distant metastasis of breast cancer in clinical practice.

Overexpression of lncRNA HOXA11-AS promotes cell epithelial-mesenchymal transition by repressing miR-200b in non-small cell lung cancer

Background

Recent studies have verified that long noncoding RNAs (lncRNAs) involved in many biological functions and play crucial roles in human cancers progression, the study aimed to detect the association between long non-coding RNA HOXA11-AS and epithelial–mesenchymal transition (EMT) process in non-small cell lung cancer (NSCLC).

Methods

The lncRNA HOXA11-AS expression levels were determined by quantitative real-time polymerase chain reaction (qRT-PCR) assays in 78 paired of tumor tissue and adjacent normal tissue samples in NSCLC patients. Kaplan–Meier survival curves and log-rank test was used to examine the association between lncRNA HOXA11-AS expression and the over survival time in NSCLC patients. Transwell invasion assay was performed to detect the cell invasion ability. QRT-PCR and western-blot analysis detected the mRNA and protein expression of EMT related transcription factors ZEB1/ZEB2, Snail1/2 and EMT marker E-cadherin and N-cadherin in NSCLC cells. RIP and Chromatin immunoprecipitation assays were performed to analyze the association between lncRNA HOXA11-AS and miR-200b expression in NSCLC cells.

Results

The lncRNA HOXA11-AS expression levels were significantly higher in NSCLC tissues compared with adjacent normal tissues and higher HOXA11-AS expression levels had a poor prognosis in NSCLC patients. Furthermore, knockdown of lncRNA HOXA11-AS in A549 and H1299 cells dramatically inhibited cell invasive abilities. Besides, the transcription levels and protein levels of EMT related transcription factors ZEB1/ZEB2, Snail1/2, and EMT maker N-cadherin were down-regulated after lncRNA HOXA11-AS was knocked down, but the mRNA and protein expression levels of EMT maker E-cadherin was increasing in A549 and H1299 cells. The mechanistic findings showed demonstrated that HOXA11-AS interacted with EZH2 and DNMT1 and recruited them to the miR-200b promoter regions to repress miR-200b expression in NSCLC cells, which promoted cell EMT in NSCLC.

Conclusions

Our results showed that up-regulation of lncRNA HOXA11-AS predicted a poor prognosis and lncRNA HOXA11-AS promoted cell epithelial–mesenchymal transition (EMT) by inhibiting miR-200b expression in NSCLC.

mTFkb: a knowledgebase for fundamental annotation of mouse transcription factors

Transcription factors (TFs) are well-known important regulators in cell biology and tissue development. However, in mouse, one of the most widely-used model species, currently the vast majority of the known TFs have not been functionally studied due to the lack of sufficient annotations. To this end, we collected and analyzed the whole transcriptome sequencing data from more than 30 major mouse tissues and used the expression profiles to annotate the TFs. We found that the expression patterns of the TFs are highly correlated with the histology of the tissue types thus can be used to infer the potential functions of the TFs. Furthermore, we found that as many as 30% TFs display tissue-specific expression pattern, and these tissue-specific TFs are among the key TFs in their corresponding tissues. We also observed signals of divergent transcription associated with many TFs with unique expression pattern. Lastly, we have integrated all the data, our analysis results as well as various annotation resources to build a web-based database named mTFkb freely accessible at http://www.myogenesisdb.org/mTFkb/. We believe that mTFkb could serve as a useful and valuable resource for TF studies in mouse.

Long non-coding RNA HOXA11-AS functions as a competing endogenous RNA to regulate ROCK1 expression by sponging miR-124-3p in osteosarcoma

Long non-coding RNAs (lncRNAs) have been strongly associated with various types of cancer. this study was to explore the critical role of lncRNA HOXA11-AS in osteosarcoma (OS) progression. Briefly, we should that the expression of HOXA11-AS was upregulated in OS tissues and cell lines. The high expression of HOXA11-AS was associated with advanced clinical stage, distant metastasis and poor overall survival of OS. In addition, We found that HOXA11-AS silencing suppressed OS cells proliferation, invasion and induced cell arrest in G0/G1 phase. Furthermore, our data showed that HOXA11-AS acts as an endogenous sponge by directly binding miR-124-3p, and decreasing the expression of miR-124-3p. Moreover, we found that HOXA11-AS may regulate tumor progression by affecting miR-124-3p targets, and ROCK1 expression. To conclude, our study helps to elucidate the effectiveness of HOXA11-AS promotion on OS cell proliferation and metastasis. A better understanding of interaction mechanism between HOXA11-AS-miR-124-3p-ROCK1 signaling axis may be a step forward in the development of new therapeutic strategies for the treatment of OS.

Over-expressed long noncoding RNA HOXA11-AS promotes cell cycle progression and metastasis in gastric cancer

Background

Long noncoding RNAs (lncRNAs) have emerged as critical regulators in a variety of human cancers, including gastric cancer (GC). However, the function and mechanisms responsible for these molecules in GC are not fully understood. In our previous study, we found that GC associated lncRNA HOXA11-AS is significantly upregulated in GC tissues. Over-expressed HOXA11-AS promotes GC cells proliferation and invasion through scaffolding the chromatin modification factors PRC2, LSD1 and DNMT1.

Methods

HOXA11-AS expression levels in GC cells was detected by quantitative real-time PCR (qPCR). HOXA11-AS siRNAs and overexpression vector were transfected into GC cells to down-regulate or up-regulate HOXA11-AS expression. In vitro and in vivo assays were performed to investigate the functional role of HOXA11-AS in GC cells cell cycle progression, invasion and metastasis. RIP and ChIP assays were used to determine the mechanism of HOXA11-AS’s regulation of underlying targets.

Results

We found that knockdown of HOXA11-AS induced GC cells G0/G1 phase arrest and suppressed GC cells migration, invasion and metastasis in vivo. Moreover, mechanistic investigation showed that HOXA11-AS could interact with WDR5 and promote β-catenin transcription, bind with EZH2 and repress P21 transcription, and induce KLF2 mRNA degradation via interacting with STAU1.

Conclusions

Taken together, these findings show that HOXA11-AS not only could promote GC cells migration and invasion in vitro, but also promotes GC cells metastasis in vivo, at least in part, by regulating β-catenin and KLF2.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-017-0651-6) contains supplementary material, which is available to authorized users.