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

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.

Abnormal methylation of HOXA11 promoter promotes tumor progression in testicular germ cell tumor

OBJECTIVE

To investigate the methylation of HOXA11 gene promoter in testicular germ cell tumor (GCT).

METHOD

The clinicopathological data of 63 patients with primary testicular GCT who underwent surgery during Apr. 2019 to Mar. 2021, were retrospectively analyzed. Their GCT tissue and paraneoplastic testicular tissue were obtained, and genomic DNA was extracted from both. The methylation of HOXA11 gene promoter region was detected by methylation-specific PCR (MSP). The incidence of HOXA11 methylation in testicular GCT and adjacent tissues was compared, and the connection between methylation level in testicular GCT and clinicopathologic features of patients was statistically analyzed. Testicular GCT cells were treated with methylated transferase inhibitor 5-Aza-dC in vitro, and HOXA11 mRNA expression was detected by real-time PCR.

RESULTS

The positive rate of HOXA11 promoter methylation in testicular GCT tissues was notably higher than that of paired adjacent tissues (P<0.05). The abnormal methylation of HOXA11 gene promoter was correlated with lymph node metastasis and TNM stage in patients (P<0.05). HOXA11 mRNA expression in testicular GCT cells treated with 5-Aza-dC was increased (P<0.05).

CONCLUSION

Abnormal methylation of HOXA11 gene promoter in testicular germ cell tumor tissue inhibits transcription and expression of HOXA11 gene. The abnormal methylation of HOXA11 promoter region is tightly associated with lymph node metastasis and TNM staging in testicular germ cell tumors.

Long non-coding RNAs in cancer: multifaceted roles and potential targets for immunotherapy

Cancer remains a major global health concern with high mortality rates mainly due to late diagnosis and poor prognosis. Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in human cancer, functioning through various mechanisms including as competing endogenous RNAs (ceRNAs) and indirectly regulating miRNA expression. LncRNAs have been found to have both oncogenic and tumor-suppressive roles in cancer, with the former promoting cancer cell proliferation, migration, invasion, and poor prognosis. Recent research has shown that lncRNAs are expressed in various immune cells and are involved in cancer cell immune escape and the modulation of the tumor microenvironment, thus highlighting their potential as targets for cancer immunotherapy. Targeting lncRNAs in cancer or immune cells could enhance the anti-tumor immune response and improve cancer immunotherapy outcomes. However, further research is required to fully understand the functional roles of lncRNAs in cancer and the immune system and their potential as targets for cancer immunotherapy. This review offers a comprehensive examination of the multifaceted roles of lncRNAs in human cancers, with a focus on their potential as targets for cancer immunotherapy. By exploring the intricate mechanisms underlying lncRNA-mediated regulation of cancer cell proliferation, invasion, and immune evasion, we provide insights into the diverse therapeutic applications of these molecules.

Long non-coding RNA HOXA11-AS regulates ischemic neuronal death by targeting miR-337-3p/YBX1 signaling pathway: protective effect of dexmedetomidine

Cerebral ischemia/reperfusion (I/R) is a common neurological disease. Homeobox A11 antisense RNA (HOXA11-AS), a long non-coding RNA (lncRNA), has been demonstrated as an important regulator in diverse human cancers. However, its function and regulatory mechanism in ischemic stroke remains largely unknown. Dexmedetomidine (Dex) have received wide attraction because of its neuroprotective effects. This study aimed to explore the possible link between Dex and HOXA11-AS in protecting neuronal cells from by ischemia/reperfusion-induced apoptosis. We used oxygen-glucose deprivation and reoxygenation (OGD/R) in mouse neuroblastoma Neuro-2a cells and middle cerebral artery occlusion (MACO) mouse model to test the link. We found that Dex significantly alleviated OGD/R-induced DNA fragmentation, cell viability and apoptosis, and rescued the decreased HOXA11-AS expression after ischemic damage in Neuro-2a cells. Gain-/loss-of-function studies revealed that HOXA11-AS promoted proliferation, inhibited apoptosis in Neuro-2a cells exposed to OGD/R. Knockdown of HOXA11-AS decreased the protective effect of Dex on OGD/R cells. HOXA11-AS was found to transcriptionally regulate microRNA-337-3p (miR-337-3p) expression as evidenced by luciferase reporter assay, while miR-337-3p expression was upregulated following ischemia in vitro and in vivo. Besides, knockdown of miR-337-3p protected OGD/R-induced apoptotic death of Neuro-2a cells. Furthermore, HOXA11-AS functioned as a competing endogenous RNA (ceRNA) and competed with Y box protein 1 (Ybx1) mRNA for directly binding to miR-337-3p, which protected ischemic neuronal death. Dex treatment protected against ischemic damage and improved overall neurological functions in vivo. Our data suggest a novel mechanism of Dex neuroprotection for ischemic stroke through regulating lncRNA HOXA11-AS by targeting the miR-337-3p/Ybx1 signaling pathway, which might help develop new strategies for the therapeutic interventions in cerebral ischemic stroke.

lncRNA HOXA11-AS maintains the stemness of oral squamous cell carcinoma stem cells and reduces the radiosensitivity by targeting miR-518a-3p/PDK1

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is the most prevailing oral malignancy. The lncRNA HOXA11-AS shows prominent roles in OSCC. This study explored the effects of lncRNA HOXA11-AS on regulating OSCC stem cell stemness and radiosensitivity by targeting miR-518a-3p/PDK1.

METHODS

Human OSCC cell lines SCC9 and SCC15 were selected. CD133⁺ cancer stem cells (CSCs) were sorted by immunomagnetic beads. CD133 expression in cells and HOXA11-AS expression in SCC9, SCC15, and CD133⁺ SCC9, CD133⁺ SCC15 cells were assessed by flow cytometry and RT-qPCR. HOXA11-AS was silenced/overexpressed in SCC9, SCC15, CD133⁺ SCC9, and CD133⁺ SCC15 cells. Cell proliferation, radiosensitivity, invasion, and stem cell sphere formation ability were examined by CCK-8, colony formation, Transwell, and stem cell sphere formation. The levels of stemness-related genes (Oct4, Nanog, Sox2), miR-518a-3p, epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, Vimentin, N-cadherin), and PDK1 were assessed by RT-qPCR and Western blot assay.

RESULTS

HOXA11-AS was up-regulated in SCC9, SCC15, CD133⁺ SCC9, and CD133⁺ SCC15 cells. HOXA11-AS silencing inhibited OSCC proliferation and invasion and enhanced radiosensitivity. HOXA11-AS maintained CSC stemness in OSCC. HOXA11-AS silencing reduced CD133⁺ SCC9 and CD133⁺ SCC15 stem cell sphere formation ability, reduced stem cell stemness-related gene levels, and inhibited EMT. HOXA11-AS regulated OSCC stem cell stemness and radiosensitivity by targeting miR-518a-3p. PDK1 overexpression annulled the regulatory effects of HOXA11-AS silencing on OSCC cell stem cell stemness and radiosensitivity.

CONCLUSION

In vitro lncRNA HOXA11-AS silencing inhibited OSCC stem cell stemness by targeting the miR-518a-3p/PDK1 axis, thus enhancing OSCC cell radiosensitivity.

Long non-coding RNAs involved in retinoblastoma

INTRODUCTION

Retinoblastoma (RB) is the most common childhood tumor that can occur in the retina and develop in a sporadic or heritable form. Although various traditional treatment options have been used for patients with RB, identifying novel strategies for childhood cancers is necessary.

MATERIAL AND METHODS

Recently, molecular-based targeted therapies have opened a greater therapeutic window for RB. Long non-coding RNAs (lncRNAs) presented a potential role as a biomarker for the detection of RB in various stages.

CONCLUSION

LncRNAs by targeting several miRNA/transcription factors play critical roles in the stimulation or suppression of RB. In this review, we summarized recent progress on the functions of tumor suppressors or oncogenes lncRNAs in RB.

Long non-coding RNA HOXA11-AS protects the barrier function of corneal endothelial cells by sponging microRNA-155 to alleviate corneal endothelial injury

OBJECTIVES

Corneal endothelial cells (CECs) are extremely vulnerable to injury. In this study, the role and mechanism of action of the long non-coding RNA HOXA11-AS during corneal endothelial injury (CEI) were evaluated in vivo and in vitro.

METHODS

Scratch wounds were made to induce CEI in the corneal endothelium of rats and mice. Homeobox A11 (HOXA11)-AS expression was determined at different time points using quantitative real-time PCR. Human CECs with HOXA11-AS overexpression or downregulation were examined for survival, ferroptosis, and migration. Bioinformatics and dual-luciferase reporter assays were used to investigate the correlation between HOXA11-AS and microRNA (miR)-155.

RESULTS

HOXA11-AS expression was reduced in the corneal endothelium in a time-dependent manner. Scratch wounds triggered high rates of ferroptosis and migration in CECs and impaired cell proliferation. HOXA11-AS overexpression partially attenuated the scratch wound-induced changes in proliferation, ferroptosis, and migration, whereas silencing HOXA11-AS had the opposite effects. Moreover, HOXA11-AS served as a competing endogenous RNA of miR-155. Levels of miR-155 were upregulated in the corneal endothelium following the scratch injury, and this upregulation abolished the effect of HOXA11-AS overexpression on the behavior of CECs after injury; miR-155 inhibition counteracted the effect of HOXA11-AS silencing.

CONCLUSIONS

HOXA11-AS exerts protective effects against CEI by sponging miR-155, suggesting that these loci are treatment targets for corneal endothelial disorders.

HOXA11-OS participates in lupus nephritis by targeting miR-124-3p mediating Cyr61 to regulate podocyte autophagy

BACKGROUND

The long chain non-coding RNA HOXA11-OS was recently identified. Increasing studies have shown that HOXA11-OS has regulatory effects on genes in gastric cancer, prostate cancer, and various kidney diseases, but research on its role in systemic lupus erythematosus is still lacking. The present study aimed to investigate the role of HOXA11-OS in the regulation of podocyte autophagy in the development of lupus nephritis (LN) and its potential molecular mechanism.

METHODS

mRNA and protein expression of the target gene (i.e., Cyr61) was detected by quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence. Mouse podocytes were induced using serum immunoglobulin G (IgG) from patients with lupus and their viability was detected using the cell counting kit-8 assay. The interaction of miR-124-3p with HOXA11-OS and Cyr61 was analyzed by double luciferase reporter gene assay. Serum autoantibody levels were detected by enzyme-linked immunosorbent assay. Pathological lesions in the kidney tissue were detected by hematoxylin-eosin and periodate-Schiff staining. The independent samples t-test was used for comparing two groups, and one-way analysis of variance for comparing multiple groups.

RESULTS

HOXA11-OS was highly expressed in LN tissues, serum, and cells, and the expression of some key autophagy factors and Cyr61 was significantly increased, while miR-124-3p expression was significantly decreased. In vitro, LN-IgG inhibited podocyte activity, increased autophagy and Cyr61 expression, and aggravated podocyte injury in a time- and dose-dependent manner. As a competitive endogenous RNA of miR-124-3p, HOXA11-OS promoted the expression of Cyr61, thus enhancing the autophagy increase induced by LN-IgG and aggravating podocyte injury. Knockdown of HOXA11-OS had the opposite effect. miR-124-3p mimic or Cyr61 knockdown restored the high expression of autophagy factors and Cyr61 induced by HOXA11-OS overexpression and alleviated podocyte injury. Further in vivo experiments showed that injection of sh-HOXA11-OS adeno-associated virus downregulated HOXA11-OS and significantly alleviated renal damage in lupus mice.

CONCLUSIONS

HOXA11-OS is involved in the occurrence and development of LN by regulating podocyte autophagy through miR-124-3p/Cyr61 sponging, which may provide a good potential therapeutic target for LN.

An Axis between the Long Non-Coding RNA HOXA11-AS and NQOs Enhances Metastatic Ability in Oral Squamous Cell Carcinoma

Long non-coding RNAs (lncRNAs) play critical roles in human cancers. HOXA11 anti-sense RNA (HOXA11-AS) is an lncRNA belonging to the homeobox (HOX) gene cluster that promotes liver metastasis in human colon cancer. However, its role and mechanism of action in human oral squamous cell carcinoma (OSCC) are unclear. In this study, we investigated HOXA11-AS expression and function in human OSCC tissues and cell lines, as well as a mouse model of OSCC. Our analyses showed that HOXA11-AS expression in human OSCC cases correlates with lymph node metastasis, nicotinamide adenine dinucleotide (NAD)(P)H: quinone oxidoreductase 1 (NQO1) upregulation, and dihydronicotinamide riboside (NRH): quinone oxidoreductase 2 (NQO2) downregulation. Using the human OSCC cell lines HSC3 and HSC4, we demonstrate that HOXA11-AS promotes NQO1 expression by sponging microRNA-494. In contrast, HOXA11-AS recruits zeste homolog 2 (EZH2) to the NQO2 promoter to suppress its expression via the trimethylation of H3K27. The upregulation of NQO1 enzymatic activity by HOXA11-AS results in the consumption of flavin adenine dinucleotide (FAD), which reduces FAD-requiring glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity and suppresses glycolysis. However, our analyses show that lactic acid fermentation levels are preserved by glutaminolysis due to increased malic enzyme-1 expression, promoting enhanced proliferation, invasion, survival, and drug resistance. In contrast, suppression of NQO2 expression reduces the consumption of NRH via NQO2 enzymatic activity and increases NAD levels, which promotes enhanced stemness and metastatic potential. In mouse tumor models, knockdown of HOXA11-AS markedly suppressed tumor growth and lung metastasis. From these findings, targeting HOXA11-AS may strongly suppress high-grade OSCC by regulating both NQO1 and NQO2.

Emerging role of lncRNAs in drug resistance mechanisms in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) originates in the squamous cell lining the mucosal surfaces of the head and neck region, including the oral cavity, nasopharynx, tonsils, oropharynx, larynx, and hypopharynx. The heterogeneity, anatomical, and functional characteristics of the patient make the HNSCC a complex and difficult-to-treat disease, leading to a poor survival rate and a decreased quality of life due to the loss of important physiologic functions and aggressive surgical injury. Alteration of driver-oncogenic and tumor-suppressing lncRNAs has recently been recently in HNSCC to obtain possible biomarkers for diagnostic, prognostic, and therapeutic approaches. This review provides current knowledge about the implication of lncRNAs in drug resistance mechanisms in HNSCC. Chemotherapy resistance is a major therapeutic challenge in HNSCC in which lncRNAs are implicated. Lately, it has been shown that lncRNAs involved in autophagy induced by chemotherapy and epithelial–mesenchymal transition (EMT) can act as mechanisms of resistance to anticancer drugs. Conversely, lncRNAs involved in mesenchymal–epithelial transition (MET) are related to chemosensitivity and inhibition of invasiveness of drug-resistant cells. In this regard, long non-coding RNAs (lncRNAs) play a pivotal role in both processes and are important for cancer detection, progression, diagnosis, therapy response, and prognostic values. As the involvement of more lncRNAs is elucidated in chemoresistance mechanisms, an improvement in diagnostic and prognostic tools could promote an advance in targeted and specific therapies in precision oncology.

Solamargine Inhibits the Development of Hypopharyngeal Squamous Cell Carcinoma by Decreasing LncRNA HOXA11-As Expression

Hypopharyngeal squamous cell carcinoma (HSCC) is one of the high mortality cancers with a poor prognosis, which is driving the development of new chemotherapeutic agents. We identified the anticancer effects of a natural compound, solamargine (SM), on FaDU cells and explored its mechanism in terms of non-coding RNA. It was observed that SM inhibited the proliferation of FaDU cells with an IC₅₀ of 5.17 μM. High-throughput sequencing data revealed that lncRNA HOXA11-AS was significantly downregulated in cells co-incubated with SM. Further assays demonstrated that SM-induced downregulation of lncRNA HOXA11-AS showed important implications for apoptosis. Given the properties of HOXA11-AS as a miR-155 sponge, we further confirmed that SM upregulated the expression of miR-155 in FaDU cells. C-Myc is a transcription factor that regulates cell differentiation and apoptosis, whose mRNA is considered to be targeted by miR-155. We showed that c-Myc expression was downregulated by SM and accompanied by increased apoptosis, which was consistent with the findings of transcriptome sequencing. Furthermore, SM administration suppressed xenograft tumor growth in a xenograft mouse model in vivo. In the light of the aforementioned findings, our results suggested that SM downregulated the expression of HOXA11-AS, which in turn induces apoptosis by downregulating c-Myc in FaDU, providing evidence for the anticancer effect of SM on HSCC and uncovering the effect of SM on non-coding RNAs as, at least partly, a mechanism of action.

Natural antisense RNA Foxk1-AS promotes myogenic differentiation by inhibiting Foxk1 activity

Background

Natural antisense RNAs are RNA molecules that are transcribed from the opposite strand of either protein-coding or non-protein coding genes and have the ability to regulate the expression of their sense gene or several related genes. However, the roles of natural antisense RNAs in the maintenance and myogenesis of muscle stem cells remain largely unexamined.

Methods

We analysed myoblast differentiation and regeneration by overexpression and knockdown of Foxk1-AS using lentivirus and adeno-associated virus infection in C2C12 cells and damaged muscle tissues. Muscle injury was induced by BaCl₂ and the regeneration and repair of damaged muscle tissues was assessed by haematoxylin–eosin staining and quantitative real-time PCR. The expression of myogenic differentiation-related genes was verified via quantitative real-time PCR, Western blotting and immunofluorescence staining.

Results

We identified a novel natural antisense RNA, Foxk1-AS, which is transcribed from the opposite strand of Foxk1 DNA and completely incorporated in the 3′ UTR of Foxk1. Foxk1-AS targets Foxk1 and functions as a regulator of myogenesis. Overexpression of Foxk1-AS strongly inhibited the expression of Foxk1 in C2C12 cells and in tibialis anterior muscle tissue and promoted myoblast differentiation and the regeneration of muscle fibres damaged by BaCl₂. Furthermore, overexpression of Foxk1-AS promoted the expression of Mef2c, which is an important transcription factor in the control of muscle gene expression and is negatively regulated by Foxk1.

Conclusion

The results indicated that Foxk1-AS represses Foxk1, thereby rescuing Mef2c activity and promoting myogenic differentiation of C2C12 cells and regeneration of damaged muscle fibres.

Long non-coding RNA HOXA11-AS knockout inhibits proliferation and overcomes drug resistance in ovarian cancer

In ovarian carcinogenesis and progression, long non-coding RNAs (lncRNAs) have been shown to have a role, although the underlying processes remain a mystery. By modulating the degree of autophagy in ovarian cancer cells, we sought to learn more about the function lncRNA HOXA11-AS plays in the development of ovarian cancer. The expression of HOXA11-AS in ovarian normal cells and ovarian cancer cell lines was measured using R package and qRT-PCR. Ovarian cancer cells expressed HOXA11-AS substantially higher than normal cells, while cisplatin-resistant cells expressed HOXA11-AS significantly higher than ovarian cancer cells. Next, we studied the prognostic data of HOXA11-AS in ovarian cancer in the Tissue Cancer Genome Atlas (TCGA). In the next step, lentiviral transfection of ovarian cancer cells A2780, OVCAR3, and A2780/DDP (cisplatin-resistant) were performed, and HOXA11-AS knockdown was found to significantly inhibit cell viability, migration, and invasion of A2780 and OVCAR3 cells, and promote apoptosis by CCK-8 assay, transwell assay, cell cycle, and apoptosis assay, and promoted the sensitivity of A2780/DDP cells to cisplatin. It has been shown by the western blot test that HOXA11-AS knockdown increases the amount of cellular autophagy in cells. In contrast, adding the autophagy inhibitor 3-methyladenine (3-MA) to HOXA11-AS cells knocked down in vivo reduced its anti-tumor properties. As a whole, this study found that HOXA11-AS knockdown increased the expression of autophagy-related proteins and improved cisplatin sensitivity, decreased ovarian cancer cell proliferation, and promoted cell apoptosis. This study provides new insights into the role of HOXA11-AS in ovarian cancer regulation.

Construction of a HOXA11-AS-Interact Ed Network in Keloid Fibroblasts Using Integrated Bioinformatic Analysis and in Vitro Validation

Background: Expression of the long noncoding RNA (lncRNA) HOXA11-AS significantly increased in keloids by unclarified molecular regulation mechanisms.

Methods: Using successfully primary cultured keloid-derived fibroblasts from central region of chronic keloid tissues (sample 0), small interfering RNAs were designed and transfected into two keloid fibroblast samples (samples 1 and 2) to knockdown HOXA11-AS. One nonspecific transfection control (sample 3) and one blank control (sample 4) were used to remove nonspecific overlap from the studied group. The lncRNAs, messenger RNAs (mRNAs), and microRNAs (miRNAs) of five samples were sequenced to identify differentially expressed (DE) profiles in HOXA11-AS-knockdown keloid fibroblasts in samples 1 and 2 (by intersection), which facilitated removal of overlap with the nonspecific controls (samples 3 and 4, by union). Using stepwise bioinformatic analysis, a HOXA11-AS-interacted competing endogenous network (ceRNA) was screened based on three DE profiles.

Results: Keloid fibroblasts with or without HOXA11-AS as well as with or without nonspecific interferences were successfully constructed respectively. A total of 1,396 mRNAs and 39 lncRNAs were significantly changed in keloid fibroblast with HOXA11-AS knockdown. Simultaneously, 1,626 mRNAs and 99 lncRNAs were significantly changed in keloid fibroblast with nonspecific interference. With removal of nonspecific overlap, a lncRNA–mRNA interactive network characterized by close natural/intronic antisense relationship was initially constructed in keloid fibroblast with HOXA11-AS knockdown. Based on this network, a lncRNA–mRNA–protein interaction network was extended by integration of the human protein–protein interaction network. Significant functional genes were screened using PageRank algorithm in the extended network. Three genes, including SNED1, NIPAL3, and VTN, were validated by real-time PCR in HOXA11-AS-knockdown keloid fibroblasts. Only NIPAL3 was predicted to be a target gene for HOXA11-AS via three competing endogenous miRNAs (hsa-miRNA-19a-3p, hsa-miR-141-3p, and hsa-miR-140-5p).

Conclusion: An interactive network of HOXA11-AS–three miRNAs–NIPAL3 was predicted in keloid fibroblasts by integrative bioinformatic analysis and in vitro validation.

Long Non-coding RNA HOXA11-AS Facilitates Proliferation of Lung Adenocarcinoma Cells via Targeting the Let-7c-5p/IGF2BP1 Axis

Objective: This study investigates the relationship between the HOXA11-AS/let-7c-5p/IGF2BP1 regulatory axis and lung adenocarcinoma.

Methods: The expression levels of HOXA11-AS, let-7c-5p, and IGF2BP1 were evaluated in LUAD tissue and cell lines. Subcellular fractionation detection assay was adopted to verify the HOXA11-AS distribution in LUAD cells. The interaction relationship between let-7c-5p and HOXA11-AS or IGF2BP1 was validated by dual-luciferase reporter detection. In RNA binding protein immunoprecipitation assay, the binding relationship between HOXA11-AS and let-7c-5p was identified. The cell viability of transfected cells was tested by the Cell Counting Kit-8 assay. The mouse xenograft model was used to identify the effect of HOXA11-AS on tumor growth in vivo.

Results: Upregulation of lncRNA HOXA11-AS was found in LUAD, and suppression of HOXA11-AS could suppress the proliferative ability of LUAD cells. The let-7c-5p was expressed to be downregulated, which played an inhibitory role in LUAD cell proliferation. Let-7c-5p was negatively regulated by HOXA11-AS. HOXA11-AS promoted LUAD cell proliferation, while let-7c-5p had an inverse effect. Besides, IGF2BP1, regulated by let-7c-5p, had a positive relation with HOXA11-AS, while overexpression of IGF2BP1 could suppress the inhibition of silencing HOXA11-AS on LUAD cell proliferation. Experiments on mice confirmed that HOXA11-AS facilitated LUAD cell growth in vivo through regulating the let-7c-5p/IGF2BP1 axis.

Conclusion: HOXA11-AS promoted LUAD cell proliferation by targeting let-7c-5p/IGF2BP1, which could be potential molecular targets for LUAD.

Gene regulation by antisense transcription: A focus on neurological and cancer diseases

Advances in high-throughput sequencing over the past decades have led to the identification of thousands of non-coding RNAs (ncRNAs), which play a major role in regulating gene expression. One emerging class of ncRNAs is the natural antisense transcripts (NATs), the RNA molecules transcribed from the opposite strand of a protein-coding gene locus. NATs are known to concordantly and discordantly regulate gene expression in both cis and trans manners at the transcriptional, post-transcriptional, translational, and epigenetic levels. Aberrant expression of NATs can therefore cause dysregulation in many biological pathways and has been observed in many genetic diseases. This review outlines the involvements and mechanisms of NATs in the pathogenesis of various diseases, with a special emphasis on neurodegenerative diseases and cancer. We also summarize recent findings on NAT knockdown and/or overexpression experiments and discuss the potential of NATs as promising targets for future gene therapies.

HOXA11-AS aggravates microglia-induced neuroinflammation after traumatic brain injury

Long noncoding RNAs (lncRNAs) participate in many pathophysiological processes after traumatic brain injury by mediating neuroinflammation and apoptosis. Homeobox A11 antisense RNA (HOXA11-AS) is a member of the lncRNA family that has been reported to participate in many inflammatory reactions; however, its role in traumatic brain injury remains unclear. In this study, we established rat models of traumatic brain injury using a weight-drop hitting device and injected LV-HOXA11-AS into the right lateral ventricle 2 weeks before modeling. The results revealed that overexpression of HOXA11-AS aggravated neurological deficits in traumatic brain injury rats, increased brain edema and apoptosis, promoted the secretion of proinflammatory factors interleukin-1β, interleukin-6, and tumor necrosis factor α, and promoted the activation of astrocytes and microglia. Microglia were treated with 100 ng/mL lipopolysaccharide for 24 hours to establish in vitro cell models, and then transfected with pcDNA-HOXA11-AS, miR-124-3p mimic, or sh-MDK. The results revealed that HOXA11-AS inhibited miR-124-3p expression and boosted MDK expression and TLR4-nuclear factor-κB pathway activation. Furthermore, lipopolysaccharide enhanced potent microglia-induced inflammatory responses in astrocytes. Forced overexpression of miR-124-3p or downregulating MDK repressed microglial activation and the inflammatory response of astrocytes. However, the miR-124-3p-mediated anti-inflammatory effects were reversed by HOXA11-AS. These findings suggest that HOXA11-AS can aggravate neuroinflammation after traumatic brain injury by modulating the miR-124-3p-MDK axis. This study was approved by the Animal Protection and Use Committee of Southwest Medical University (approval No. SMU-2019-042) on February 4, 2019.

HOXA11-AS induces cisplatin resistance by modulating the microRNA-98/PBX3 axis in nasopharyngeal carcinoma

Long non-coding RNA homeobox A11-antisense RNA (HOXA11-AS) has been implicated in cisplatin (DDP) resistance in multiple types of cancer. The purpose of the present study was to investigate the role of HOXA11-AS in DDP-resistant nasopharyngeal carcinoma (NPC) cells. The expression levels of HOXA11-AS were examined using reverse transcription-quantitative PCR. Cell viability was measured using a Cell Counting Kit-8 assay, and a TUNEL assay was utilized to assess cell apoptosis. The expression levels of apoptosis-related factors (Bax and Bcl-2) were detected by western blot analysis. The interaction between microRNA-98 (miR-98) and HOXA11-AS or pre-B-cell leukemia homeobox 3 (PBX3) was demonstrated using bioinformatics analysis, dual-luciferase reporter assays and RNA immunoprecipitation assays. HOXA11-AS and PBX3 expressions levels were upregulated, whereas miR-98 levels were downregulated in DDP-resistant NPC tissues. Patients with NPC with high HOXA11-AS expression had a low survival rate. Knockdown of HOXA11-AS enhanced the DDP sensitivity of DDP-resistant NPC (5-8F/DDP and SUNE1/DDP) cells, which was demonstrated by the accelerated apoptosis. In addition, HOXA11-AS inhibited the expression levels of miR-98 through direct interaction. Furthermore, miR-98 inhibition counteracted the inductive effect of HOXA11-AS-knockdown on the DDP sensitivity of NPC cells. PBX3 was a target of miR-98 and was positively modulated by HOXA11-AS. Overexpression of PBX3 reversed the suppressive effect of HOXA11-AS silencing on the DDP resistance of NPC cells. The data demonstrated that HOXA11-AS enhanced DDP resistance in NPC via the miR-98/PBX3 axis, providing a potential therapeutic target for patients with DDP-resistant NPC.

Identification and Validation of a Potential Prognostic 7-lncRNA Signature for Predicting Survival in Patients with Multiple Myeloma

BACKGROUND

An increasing number of studies have indicated that the abnormal expression of certain long noncoding RNAs (lncRNAs) is linked to the overall survival (OS) of patients with myeloma.

METHODS

Gene expression data of myeloma patients were downloaded from the Gene Expression Omnibus (GEO) database (GSE4581 and GSE57317). Cox regression analysis, Kaplan-Meier, and receiver operating characteristic (ROC) analysis were performed to construct and validate the prediction model. Single sample gene set enrichment (ssGSEA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to predict the function of a specified lncRNA.

RESULTS

In this study, a seven-lncRNA signature was identified and used to construct a risk score system for myeloma prognosis. This system was used to stratify patients with different survival rates in the training set into high-risk and low-risk groups. Test set, the entire test set, the external validation set, and the myeloma subtype achieved the authentication of the results. In addition, functional enrichment analysis indicated that 7 prognostic lncRNAs may be involved in the tumorigenesis of myeloma through cancer-related pathways and biological processes. The results of the immune score showed that IF_I was negatively correlated with the risk score. Compared with the published gene signature, the 7-lncRNA model has a higher C-index (above 0.8).

CONCLUSION

In summary, our data provide evidence that seven lncRNAs could be used as independent biomarkers to predict the prognosis of myeloma, which also indicated that these 7 lncRNAs may be involved in the progression of myeloma.

Exploring the secrets of brain transcriptional regulation: developing methodologies, recent significant findings, and perspectives

Exploring and revealing the secret of the function of the human brain has been the dream of mankind and science. Delineating brain transcriptional regulation has been extremely challenging, but recent technological advances have facilitated a deeper investigation of molecular processes in the brain. Tracing the molecular regulatory mechanisms of different gene expression profiles in the brain is divergent and has made it possible to connect spatial and temporal variations in gene expression to distributed properties of brain structure and function. Here, we review the molecular diversity of the brain among rodents, non-human primates and humans. We also discuss the molecular mechanism of non-coding DNA/RNA at the transcriptional/post-transcriptional level based on recent technical advances to highlight an improved understanding of the complex transcriptional network in the brain. Spatiotemporal and single-cell transcriptomics have attempted to gain novel insight into the development and evolution of the brain as well as the progression of human diseases. Although it is clear that the field is developing and challenges remain to be resolved, the impressive recent progress provides a solid foundation to better understand the brain and evidence-based recommendations for the diagnosis and treatment of brain diseases.

Nanodiamond-based microRNA delivery system promotes pluripotent stem cells toward myocardiogenic reprogramming

BACKGROUND

Gene therapy is the advanced therapeutics for supplying or replacing the genetic material in patients with inherited disorders. Recent clinical studies have made some progress in a wide range of applications, including monogenic disorders, neurodegenerative diseases, malignant tumors, and congenital diseases. Heart diseases, especially myocardial ischemia, remain one of the leading causes of mortality worldwide and usually result in irreparable cardiomyocyte damage and severe heart failure.

METHODS

Most advances in induced pluripotent stem cell (iPSC) technologies for promoting regenerative medicine and stem cell research. However, the driver molecules of myocardial-lineage differentiation and the functional reconstruction capacity of iPSC-derived cardiomyocytes are still an open question. Nanomedicine-based gene delivery provided a crucial platform to carry on the biogenomic materials for equipping functionalities and engineering the living organ environment. Nanodiamond (ND), a carbon-based nanomaterial, has been discovered and shown the high biocompatible and less toxicity for transporting protein, drug, and genomic plasmids.

RESULTS

Here, we applied ND as a gene delivery vehicle to carry microRNA (miR-181a), and then transfected into iPS to promote cardiomyocyte-lineage differentiation. Notably, miR-181a plays a key role in iPS-derived cardiomyocyte differentiation which directly targets Hox-A11, leading to elevated MyoD expression and enhanced cardiomyocyte differentiation.

CONCLUSION

Our study demonstrated that miR-181a promotes iPSC differentiation into functional cardiomyocytes. Delivery of NANO-DIAMOND-miR-181a may host clinical potential to enhance the differentiation and recovery of the cardiogenic function in injured cardiomyocytes.

Long Noncoding RNA HOXA11-AS and Transcription Factor HOXB13 Modulate the Expression of Bone Metastasis-Related Genes in Prostate Cancer

Long noncoding RNAs (lncRNAs) are emerging as critical regulators of gene expression, which play fundamental roles in cancer development. In this study, we found that homeobox A11 antisense RNA (HOXA11-AS), a highly expressed lncRNA in cell lines derived from prostate cancer bone metastases, promoted the cell invasion and proliferation of PC3 prostate cancer cells. Transcription factor homeobox B13 (HOXB13) was identified as an upstream regulator of HOXA11-AS.HOXA11-AS regulated bone metastasis-associated C-C motif chemokine ligand 2 (CCL2)/C-C chemokine receptor type 2 (CCR2) signaling in both PC3 prostate cancer cells and SaOS2 osteoblastic cells. The HOXB13/HOXA11-AS axis also regulated integrin subunits (ITGAV and ITGB1) specific to prostate cancer bone metastasis. HOXB13, in combination with HOXA11-AS, directly regulated the integrin-binding sialoprotein (IBSP) promoter. Furthermore, conditioned medium containing HOXA11-AS secreted from PC3 cells could induce the expression of CCL2 and IBSP in SaOS2 osteoblastic cells. These results suggest that prostate cancer HOXA11-AS and HOXB13 promote metastasis by regulation of CCL2/CCR2 cytokine and integrin signaling in autocrine and paracrine manners.

Upregulated Long Non-Coding RNA LL22NC03-N64E9.1 Promotes the Proliferation and Migration of Human Breast Cancer Cells by Silencing Kruppel-Like Factor 2 Expression

Introduction

Recently, the significant regulatory effects of lncRNAs on the oncogenesis and growth of tumor have been demonstrated by an increasing number of research projects. A previous study showed that LL22NC03-N64E9.1 could promote the development of colorectal cancer, especially via enhanced cell proliferation. Similarly, this lncRNA should have comparable functions in breast cancer (BC), which requires in-depth investigation. Therefore, this study was designed to explore the correlation of LL22NC03-N64E9.1 with BC.

Methods

qRT-PCR was used to assess the relative expression of LL22NC03-N64E9.1 in BC tissues. Cell viability examination and colony formation experiments were performed to investigate the role of LL22NC03-N64E9.1 in BC cell’s proliferation. Transwell assays were used to explore the effects of LL22NC03-N64E9.1 on BC cell’s migration. RNA immunoprecipitation, chromosome immunoprecipitation assay and rescue experiments were performed to analyze the association of LL22NC03-N64E9.1 with target proteins and genes in BC cells.

Results

We identified that LL22NC03-N64E9.1 is an oncogene, upregulated in BC, which was verified in a cohort of 48 pairs of BC tissues. Based on the loss-of-function experiments, silencing LL22NC03-N64E9.1 expression significantly inhibited malignancy progression. In terms of the mechanism, LL22NC03-N64E9.1 acted on the enhancer of zeste homolog 2 (EZH2) by direct binding, which promoted BC cell growth. Furthermore, in the promoters of KLF2, the trimethylation of H3K27 could be regulated by LL22NC03-N64E9.1 as the mediator.

Conclusion

Relying on the LL22NC03-N64E9.1/EZH2/KLF2 pathway, the lncRNA LL22NC03-N64E9.1 was significantly associated with BC development and could, therefore, be a potential therapeutic target to block BC growth.

Liquid lncRNA Biopsy for the Evaluation of Locally Advanced and Metastatic Squamous Cell Carcinomas of the Head and Neck

Background: Long non-coding RNA (lncRNA) are RNA molecules that are more than 200 nucleotides long and have the ability to modify the activity of genes. They can be found in both healthy and cancer tissues, as well as in plasma, saliva and other bodily fluids. They can also be used as biomarkers of early detection, prognosis and chemotherapy resistance in several cancer types. Treatment of head and neck squamous cell carcinoma (HNSCC) patients with locally advanced disease is still difficult, and choice of treatment should be based on more precise and available biomarkers, such as those obtained from a liquid biopsy. For improvement of treatment efficacy, identification and clinical implementation of new biomarkers are of the utmost importance. Methods: Plasma samples drawn before (p1) and three cycles post (p2) (TPF: docetaxel, cisplatin, 5-fluorouracil/PF: cisplatin, 5-fluorouracil) chemotherapy from 53 HNSCC patients (17 with locally advanced and 36 with metastatic disease) and 14 healthy volunteers were studied. Expression levels of 90 lncRNA expression were analyzed using the qRT-PCR method, and the obtained results were compared between proper groups. Statistical analyses were carried out using Jupyter Notebooks (5.7.2), Python (ver. 3.6) and GraphPad Prism 8. Results: The study demonstrated the differences between the expressions of several lncRNA in cancer patients' and healthy volunteers' plasma, as well as between locally advanced and metastatic patients' groups. A correlation between the response to systemic therapy and lncRNA expression levels was observed. Patients with a (high/low) expression of Alpha 250 and Emx2os showed statistically significant differences in progression free survival (PFS), as well as for overall survival (OS) depending on the level of Alpha 250, snaR, SNHG1. The univariate and multivariate Cox regression model showed Alpha 250 as the best prognostic factor for HNSCC patients. Conclusions: Liquid biopsies based on lncRNAs are promising diagnostic tools that can be used to differentiate between those with cancer and healthy individuals. Additionally, they can also serve as biomarkers for chemotherapy resistance. An identified, circulating lncRNA Alpha 250 seems to prove the best prognostic biomarker, associated with extended PFS and OS, and should be validated in a larger cohort in the future.

Natural antisense transcripts in the biological hallmarks of cancer: powerful regulators hidden in the dark

Natural antisense transcripts (NATs), which are transcribed from opposite strands of DNA with partial or complete overlap, affect multiple stages of gene expression, from epigenetic to post-translational modifications. NATs are dysregulated in various types of cancer, and an increasing number of studies focusing on NATs as pivotal regulators of the hallmarks of cancer and as promising candidates for cancer therapy are just beginning to unravel the mystery. Here, we summarize the existing knowledge on NATs to highlight their underlying mechanisms of functions in cancer biology, discuss their potential roles in therapeutic application, and explore future research directions.

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.

Genome-wide DNA methylation profile analysis in thoracic ossification of the ligamentum flavum

Thoracic ossification of the ligamentum flavum (TOLF) causes serious spinal canal stenosis. The underlying aetiology may relate to genetic and inflammatory factors. DNA methylation plays a critical role in osteogenesis and inflammation, whereas there is no genome‐wide DNA methylation analysis about TOLF. The two subtypes of TOLF (single‐level and multiple‐level) have distinct clinical features. Using micro‐computed tomography (micro‐CT), we showed the ossification arose from the joint between two vertebrae at one/both sides of ligament flavum. With Illumina Infinium Human Methylation 850 BeadChip arrays, genome‐wide DNA methylation profile was measured in ligament flavum of eight healthy and eight TOLF samples. Only 65 of the differentially methylated cytosine‐phosphate‐guanine dinucleotides were found in both subtype groups. Principal component analysis and heat map analysis showed a different methylation pattern in TOLF samples, and methylation patterns of two subtypes are also distinct. The Gene Ontology enrichment analysis was significantly enriched in differentiation and inflammation. Pyrosequencing analysis and quantitative real‐time polymerase chain reaction were performed to validate the arrays results and expression levels, to test six differentially methylated genes (SLC7A11, HOXA10, HOXA11AS, TNIK, homeobox transcript antisense RNA, IFITM1), using another independent samples (P < 0.05). Our findings first demonstrated an altered Genome‐wide DNA methylation profile in TOLF, and implied distinct methylated features in two subtypes.

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.

lncRNA ZFAS1 promotes lung fibroblast-to-myofibroblast transition and ferroptosis via functioning as a ceRNA through miR-150-5p/SLC38A1 axis

Pulmonary fibrosis (PF) is a lethal fibrotic lung disease. The role of lncRNAs in multiple diseases has been confirmed, but the role and mechanism of lncRNA zinc finger antisense 1 (ZFAS1) in the progression of PF need to be elucidated further. Here, we found that lncRNA ZFAS1 was upregulated in bleomycin (BLM)-induced PF rats lung tissues and transforming growth factor-β1 (TGF-β1)-treated HFL1 cells, and positively correlated with the expression of solute carrier family 38 member 1 (SLC38A1), which is an important regulator of lipid peroxidation. Moreover, knockdown of lncRNA ZFAS1 significantly alleviated TGF-β1-induced fibroblast activation, inflammation and lipid peroxidation. In vivo experiments showed that inhibition of lncRNA ZFAS1 abolished BLM-induced lipid peroxidation and PF development. Mechanistically, silencing of lncRNA ZFAS1 attenuated ferroptosis and PF progression by lncRNA ZFAS1 acting as a competing endogenous RNA (ceRNA) and sponging miR-150-5p to downregulate SLC38A1 expression. Collectively, our studies demonstrated the role of the lncRNA ZFAS1/miR-150-5p/SLC38A1 axis in the progression of PF, and may provide a new biomarker for the treatment of PF patients.

lncRNA HOXA11-AS Promotes Proliferation and Migration via Sponging miR-155 in Hypopharyngeal Squamous Cell Carcinoma

Hypopharyngeal squamous cell carcinoma (HSCC) remains one of the most lethal malignancies in the head and neck. Long noncoding RNA (lncRNA) HOXA11-AS is proven to function as an oncogene and a therapeutic target in various tumors. Our previous study and others have demonstrated that HOXA11-AS is one of the most upregulated lncRNAs in HSCC. However, the role of HOXA11-AS in HSCC has not yet been identified. The current study demonstrated that the expression of HOXA11-AS was significantly upregulated in HSCC tumors and was positively associated with lymph node metastasis. Moreover, functional experiments revealed that HOXA11-AS knockdown suppressed the proliferation and migration potential in FaDu cells. Furthermore, luciferase reporter gene assay combined with cellular functional experiments demonstrated that HOXA11-AS functioned as a molecular sponge for miR-155, and inhibition of miR-155 attenuated the suppressive effect of HOXA11-AS knockdown on the aggressive phenotype in HSCC. This study identifies a tumor-promoting role of HOXA11-AS in HSCC and suggests HOXA11-AS might be a potential diagnostic and therapeutic target for HSCC.

Construction of a prognosis‑associated long noncoding RNA‑mRNA network for multiple myeloma based on microarray and bioinformatics analysis

At present, the association between prognosis-associated long noncoding RNAs (lncRNAs) and mRNAs is yet to be reported in multiple myeloma (MM). The aim of the present study was to construct prognostic models with lncRNAs and mRNAs, and to map the interactions between these lncRNAs and mRNAs in MM. LncRNA and mRNA data from 559 patients with MM were acquired from the Genome Expression Omnibus (dataset GSE24080), and their prognostic values were calculated using the survival package in R. Multivariate Cox analysis was used on the top 20 most significant prognosis-associated mRNAs and lncRNAs to develop prognostic signatures. The performances of these prognostic signatures were tested using the survivalROC package in R, which allows for time-dependent receiver operator characteristic (ROC) curve estimation. Weighted correlation network analysis (WGCNA) was conducted to investigate the associations between lncRNAs and mRNAs, and a lncRNA-mRNA network was constructed using Cytoscape software. Univariate Cox regression analysis identified 39 lncRNAs and 1,445 mRNAs that were significantly associated with event-free survival of MM patients. The top 20 most significant survival-associated lncRNAs and mRNAs were selected as candidates for analyzing independent MM prognostic factors. Both signatures could be used to separate patients into two groups with distinct outcomes. The areas under the ROC curves were 0.739 for the lncRNA signature and 0.732 for the mRNA signature. In the lncRNA-mRNA network, a total of 143 mRNAs were positively or negatively associated with 23 prognosis-associated lncRNAs. NCRNA00201, LOC115110 and RP5-968J1.1 were the most dominant drivers. The present study constructed a model that predicted prognosis in MM and formed a network with the corresponding prognosis-associated mRNAs, providing a novel perspective for the clinical diagnosis and treatment of MM, and suggesting novel directions for interpreting the mechanisms underlying the development of MM.

Long non-coding RNA HOXA11-AS upregulates Cyclin D2 to inhibit apoptosis and promote cell cycle progression in nephroblastoma by recruiting forkhead box P2

Long non-coding RNAs (lncRNAs) have been highlighted to play key roles in the gene regulatory network, and the dysregulation of lncRNAs has also been implicated in various malignancies. However, little is known regarding the expression of lncRNA and their functions in the progression of nephroblastoma. Thus, the present study aimed to explore the potential role of homeobox A11 (HOXA11)-AS in nephroblastoma. Microarray-based analysis was initially applied to screen the differentially expressed lncRNAs, and HOXA11-AS was selected as the candidate. The HFWT cells were performed with gain- and loss-of function test to evaluate the role of HOXA11-AS in cell cycle and apoptosis in nephroblastoma using flow cytometry and Western blots. Moreover, the relationship between HOXA11-AS and forkhead box P2 (FOXP2) was verified by Cross-linking RIP, and the direct interaction between HOXA11-AS and Cyclin D2 (CCND2) was detected using a dual luciferase reporter gene assay. Tumor formation in nude mice was used to investigate the effect of HOXA11-AS in vivo. HOXA11-AS was found to be highly expressed in the nephroblastoma. Furthermore, the silencing of HOXA11-AS promoted apoptosis and cell cycle arrest at the G1/S phase in nephroblastoma through the transcription factor FOXP2 to downregulate the expression of CCND2. Consistently, the tumor formation data in nude mice verified the results in vivo. Taken together, silencing of HOXA11-AS promotes apoptosis and inhibits the cell cycle entry in nephroblastoma by recruiting the transcription factor FOXP2 to downregulate the expression of CCND2, highlighting a promising novel direction for future nephroblastoma treatment.

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.

LncRNA HOXA11-AS promotes OSCC progression by sponging miR-98-5p to upregulate YBX2 expression

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a type of oral malignancy. Long non-coding RNAs (lncRNAs) have been shown to be related to the occurrence and development of many cancers. Here, we aimed to study the role and molecular mechanism of lncRNA Homeobox A11 antisense RNA (HOXA11-AS) in OSCC.

METHODS

The expression levels of HOXA11-AS, miR-98-5p and Y box binding protein 2 (YBX2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell counting kit-8 (CCK-8), flow cytometry and transwell assays were utilized to determine the proliferation, apoptosis, migration and invasion of OSCC cells. Western blot (WB) analysis was conducted to measure the levels of apoptosis, epithelial-mesenchymal transition (EMT), proliferation-related proteins and YBX2 protein. Besides, Dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pull down assays were carried out to examine the relationship among HOXA11-AS, miR-98-5p and YBX2. The mice xenograft models were constructed to further determine the effect of HOXA11-AS on OSCC tumor growth in vivo.

RESULTS

HOXA11-AS was highly expressed in OSCC tissues and cells. Knockdown of HOXA11-AS significantly reduced proliferation, migration, invasion and EMT, while promoted apoptosis of OSCC cells. MiR-98-5p was a target of HOXA11-AS, and its inhibitor could revert the inhibition effect of silenced-HOXA11-AS on the progression of OSCC. Also, YBX2 was a target of miR-98-5p, and its overexpression could invert the suppression effect of miR-98-5p overexpression on the progression of OSCC. YBX2 expression was regulated by HOXA11-AS and miR-98-5p. Furthermore, HOXA11-AS silencing could reduce the tumor growth of OSCC in vivo.

CONCLUSION

HOXA11-AS plays an active role in the progression of OSCC, and the discovery of HOXA11-AS/miR-98-5p/YBX2 axis provides new therapeutic targets for OSCC.

LncRNA HOXA11-AS regulates calcium oxalate crystal-induced renal inflammation via miR-124-3p/MCP-1

Long noncoding RNA (lncRNA) has been suggested to play an important role in a variety of diseases over the past decade. In a previous study, we identified a novel lncRNA, termed HOXA11‐AS, which was significantly up‐regulated in calcium oxalate (CaOx) nephrolithiasis. However, the biological function of HOXA11‐AS in CaOx nephrolithiasis remains poorly defined. Here, we demonstrated that HOXA11‐AS was significantly up‐regulated in CaOx nephrolithiasis both in vivo and in vitro. Gain‐/loss‐of‐function studies revealed that HOXA11‐AS inhibited proliferation, promoted apoptosis and aggravated cellular damage in HK‐2 cells exposed to calcium oxalate monohydrate (COM). Further investigations showed that HOXA11‐AS regulated monocyte chemotactic protein 1 (MCP‐1) expression in HK‐2 cell model of CaOx nephrolithiasis. In addition, online bioinformatics analysis and dual‐luciferase reporter assay results showed that miR‐124‐3p directly bound to HOXA11‐AS and the 3'UTR of MCP‐1. Furthermore, rescue experiment results revealed that HOXA11‐AS functioned as a competing endogenous RNA to regulate MCP‐1 expression through sponging miR‐124‐3p and that overexpression of miR‐124‐3p restored the inhibitory effect of proliferation, promotion effects of apoptosis and cell damage induced by HOXA11‐AS overexpression. Taken together, HOXA11‐AS mediated CaOx crystal–induced renal inflammation via the miR‐124‐3p/MCP‐1 axis, and this outcome may provide a good potential therapeutic target for nephrolithiasis.

High Tiam1 expression predicts positive lymphatic metastasis and worse survival in patients with malignant solid tumors: a systematic review and meta-analysis

Background

Many studies have explored the prognostic value of T-cell lymphoma invasion and metastasis inducing factor 1 (Tiam1) and its association with lymphatic metastasis in malignant solid tumors, but the conclusions remain controversial. Therefore, we performed a meta-analysis to systematically assess the prognostic value of Tiam1 expression and its association with lymphatic metastasis in malignant solid tumors.

Methods

We searched eligible studies in PubMed, Web of Science and EMBASE databases (from inception up to October 2018). The combined HR with 95% CI was used to estimate the prognostic value of Tiam1 expression. The correlation between Tiam1 expression and lymphatic metastasis was assessed using the combined odds ratio (OR) with 95% CI.

Results

A total of 17 studies with 2,228 patients with solid tumors were included in this meta-analysis. The overall estimated results showed that high Tiam1 expression was significantly associated with shorter overall survival (HR= 2.08, 95% CI: 1.62-2.68, P<0.01), and disease-free survival (HR = 1.86, 95% CI: 1.49-2.32, P<0.01). Besides, we also found that there was a close relationship between high Tiam1 expression and positive lymphatic metastasis (OR=2.63; 95% CI: 1.79-3.84, P<0.01).

Conclusion

High Tiam1 expression was significantly associated with shorter survival and positive lymphatic metastasis in patients with malignant solid tumors. Therefore, Tiam1 may be a promising prognostic biomarker and an effective therapeutic target for malignant solid tumors.

An inverse interaction between HOXA11 and HOXA11-AS is associated with cisplatin resistance in lung adenocarcinoma

HOXA11, which is a member of the homeobox (HOX) gene family, and its natural antisense transcript (NAT) HOXA11-AS have been reported to be closely related to the development of lung cancer. We aimed to investigate their specific roles in cisplatin (DDP) resistance in lung adenocarcinoma (LUAD). First, we found that HOXA11 is hypermethylated and significantly downregulated in a DDP-resistant A549 cell line (A549/DDP) and LUAD tissues, while the HOXA11-AS expression level is elevated. Although HOXA11 and HOXA11-AS mRNA overlap in the 5'-untranslated region (5' UTR) and share two CpG islands, DNA methylation only regulates the expression of HOXA11. Then, we found that HOXA11 and HOXA11-AS have an inverse interaction by transfecting their siRNAs and overexpression vectors into A549 and A549/DDP cells. A dual-luciferase reporter assay further confirmed that the overlapping 5'UTR is essential for the bidirectional regulation between HOXA11 and HOXA11-AS. Functional analysis showed that knockdown of HOXA11 expression in A549 cells induced DDP resistance and activated Akt/β-catenin signaling, while overexpression of HOXA11 in A549/DDP cells increased DDP sensitivity and inhibited Akt/β-catenin signaling. Moreover, HOXA11-AS knockdown in A549 cells increased DDP sensitivity and inhibited Akt/β-catenin signaling, while the overexpression of HOXA11-AS in A549/DDP cells induced DDP resistance and activated Akt/β-catenin signaling. In conclusion, our study demonstrates that the inverse interaction between HOXA11 and HOXA11-AS promotes DDP resistance in LUAD.

LncRNA HOXA11-AS Promotes Proliferation and Cisplatin Resistance of Oral Squamous Cell Carcinoma by Suppression of miR-214-3p Expression

Drug resistance to platinum limited therapeutic options for oral squamous cell carcinoma (OSCC). In the current study, we investigated the role of lncRNA HOMEOBOX A11 (HOXA11) antisense RNA (HOXA11-AS) in OSCC resistance to cisplatin (CDDP). We used clinical tissues and OSCC cell lines and induced CDDP resistance in OSCC cells. Gain and loss of function were performed in OSCC-resistant cells. Xenograft mice were also established. HOXA11-AS expression was increased in OSCC clinical tissues and cell lines and upregulated in CDDP-resistant cells. Upregulation of HOXA11-AS promoted proliferation in CDDP-sensitive cells and inhibited CDDP-induced cytotoxicity. In contrast, downregulation of HOXA11-AS decreased proliferation in CDDP-resistant cells and increased CDDP-induced cytotoxicity. Knockdown of HOXA11-AS inhibited the tumor growth in xenograft mice injected by CDDP. Downregulation of HOXA11-AS increased apoptosis and caspase 3 activities in CDDP-resistant OSCC cells. Bioinformatics, reporter assay, and loss and gain of function assay indicated that HOXA11-AS and miR-214-3p could negatively regulate each other. miR-214-3p was decreased in OSCC clinical tissues and cell lines. We further revealed that proto-oncogene serine/threonine-protein kinase (PIM1) was the target of miR-214-3p. PIM1 expression could be negatively regulated by miR-214-3p and positively regulated by HOXA11-AS. Inhibition of PIM1 suppressed anti-miR-214-3p-induced increase of cell proliferation and decrease of apoptosis. In summary, HOXA11-AS was identified to facilitate CDDP-resistance in OSCC and miR-214-3p/PIM1 was found to be the downstream target of HOXA11-AS. The findings highlight the importance of HOXA11-AS/miR-214-3p/PIM1 axis in the drug resistance of OSCC and provide potential targets for improving chemotherapy of OSCC.

HOXA11-AS promotes the progression of oral squamous cell carcinoma by targeting the miR-518a-3p/PDK1 axis

Background

Long non-coding RNAs (lncRNAs) are promising therapeutic molecules of cancer. Here we aim to study the therapeutic effect and mechanism of a lncRNA, HOXA11-AS, in oral squamous cell carcinoma (OSCC).

Methods

OSCC tissues and adjacent matched paraneoplastic normal tissues used in this study were collected from 42 OSCC patients. The significant downregulation or upregulation of HOXA11-AS expression in OSCC cells was confirmed by quantitative real-time PCR (qRT-PCR). Bioinformatics analysis of StarBase were performed to investigate the potential microRNAs mediated by HOXA11-AS. HOXA11-AS-transfected cells or control cells were subcutaneously injected into nude mice to further determine the effects of HOXA11-AS on OSCC progression in vivo.

Results

qRT-PCR analysis indicated that HOXA11-AS expression was significantly upregulated in OSCC tissues. Functional studies revealed that HOXA11-AS significantly promotes cell proliferation, reduces the percentage of G0/G1 phase cells and enhances the cell invasion in OSCC. Bioinformatics analysis suggested that a microRNA (miRNA), miR-518a-3p, is as a target of HOXA11-AS. Alteration of miR-518a-3p levels by HOXA11-AS transduced to changes in PDK1 expression. In a mouse model of OSCC, HOXA11-AS overexpression promoted tumor growth, concomitant with reduced miR-518a-3p expression and increased PDK1 expression.

Conclusion

Taken together, our study demonstrates that HOXA11-AS/miR-518a-3p/PDK1 axis is an important regulator of OSCC progression and may serve as a potential therapeutic target in OSCC. HARMU20150128, registered at Jan, 28 2018.

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.

HOTAIR/miR-326/FUT6 axis facilitates colorectal cancer progression through regulating fucosylation of CD44 via PI3K/AKT/mTOR pathway

Metastasis is the main cause of death in colorectal cancer (CRC) patients. Aberrant fucosylation, catalyzed by the specific fucosyltransferases (FUTs), is associated with malignant behaviors. Non-conding RNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), emerge as key molecules in cancer malignancy. The aim of this study was to investigate HOTAIR/miR-326/FUT6 axis modified fucosylation on sLe^X-CD44 (HCELL), which served as E-selectin ligand during CRC progression. Higher levels of HOTAIR and FUT6 were verified in CRC tissues and cell lines, with a positive correlation. HOTAIR was associated with poor clinical prognosis of CRC. Altered HOTAIR levels influenced proliferation, aggressiveness, apoptosis and tumorigenesis of CRC cells. HOTAIR directly harbored miR-326 binding sites and regulated FUT6 expression. Further results corroborated that HOTAIR/miR-326/FUT6 axis modified α1, 3-fucosylation of CD44, which mediated CRC malignancy. Co-modulation of HOTAIR, miR-326 and FUT6 impacted α1, 3-fucosylated CD44, which further triggered PI3K/AKT/mTOR pathway. HOTAIR also mediated CRC tumorigenesis and liver metastasis in vivo. Thus, our findings indicated that HOTAIR/miR-326/FUT6 axis mediated CRC procession through α1, 3-fucosylated CD44 via PI3K/AKT/mTOR pathway. This work rendered new therapeutic targets for CRC.