Long noncoding RNA OIP5-AS1 aggravates cell proliferation, migration in gastric cancer by epigenetically silencing NLRP6 expression via binding EZH2

Expression of Pivotal Long Non-coding RNAs Implicated in Gastric Cancer: A Bioinformatic and Clinical Study

Gastric cancer (GC) is a prominent public health issue and ranks as the third most prevalent cause of cancer-related mortality on a global scale. The role of long non-coding RNAs (lncRNAs) in cancer is not yet fully understood, particularly in relation to GC development. The objective of this study was to examine the expression levels of lncRNAs in GC tissues using a bioinformatics-based ranking approach. A bioinformatics methodology was employed to prioritize lncRNAs that are hypothesized to play a role in GC tumorigenesis. Moreover, a selection was made for experimental validation of the highest-ranked lncRNAs, which include HCG18, OIP5-AS1, FGD5-AS1, and NORAD. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR) was employed to confirm the results obtained from bioinformatics analysis in a total of 35 GC samples and their corresponding adjacent non-tumoral samples. Receiver operating characteristic (ROC) curves and the corresponding area under the ROC curve (AUC) were utilized to evaluate the diagnostic efficacy of the lncRNAs. The bioinformatics analysis revealed that the lncRNA HCG18 is the highest-ranked lncRNA associated with GC. Furthermore, the expression levels of HCG18, OIP5-AS1, FGD5-AS1, and NORAD were found to be significantly elevated in GC samples when compared to adjacent non-tumoral samples. The calculated values for the AUC of HCG18, OIP5-AS1, FGD5-AS1, and NORAD were 0.80, 0.74, 0.73, and 0.71, respectively. The results of the study indicate that the lncRNAs HCG18, OIP5-AS1, FGD5-AS1, and NORAD may play a role in the development of GC. Additionally, the present study revealed that utilizing bioinformatic techniques can prove to be a highly effective strategy in identifying potential lncRNAs pertinent to the progression of GC.

EZH2-interacting lncRNAs contribute to gastric tumorigenesis; a review on the mechanisms of action

Gastric cancer (GC) remains one of the deadliest malignancies worldwide, demanding new targets to improve its diagnosis and treatment. Long non-coding RNAs (lncRNAs) are dysregulated through gastric tumorigenesis and play a significant role in GC progression and development. Recent studies have revealed that lncRNAs can interact with histone-modifying polycomb protein, enhance Zeste Homolog 2 (EZH2), and mediate its site-specific functioning. EZH2, which functions as an oncogene in GC, is the catalytic subunit of the PRC2 complex that induces H3K27 trimethylation and epigenetically represses gene expression. EZH2-interacting lncRNAs can recruit EZH2 to the promoter regions of various tumor suppressor genes and cause their transcriptional deactivation via histone methylation. The interactions between EZH2 and this lncRNA modulate different processes, such as cell cycle, cell proliferation and growth, migration, invasion, metastasis, and drug resistance, in vitro and in vivo GC models. Therefore, EZH2-interacting lncRNAs are exciting targets for developing novel targeted therapies for GC. Subsequently, this review aims to focus on the roles of these interactions in GC progression to understand the therapeutic value of EZH2-interacting lncRNAs further.

LncRNA OIP5-AS1 Targets the miR-140-5p/UBR5 Cascade to Promote the Development of Gastric Cancer

Gastric cancer (GC) is a malignant tumor with the highest incidence among all kinds of malignant tumors in China. Long noncoding RNAs (LncRNAs) have been reported to act as microRNA (miRNAs) sponges and thus play key roles in biological processes and pathogenesis. Thus, this study aimed to investigate the functional effects and the regulatory mechanism of lncRNA opa interacting protein 5-antisense 1 (OIP5-AS1) in gastric cancer cells. The expression of OIP5-AS1, miR-140-5p, Ubiquitin protein ligase E3 component n-recognin 5 (UBR5) was detected using quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis, migration, and invasion were assessed using Cell-Counting Kit-8 (CCK-8), Flow cytometry, and Transwell assays. UBR5 protein level was detected by Western blot. Binding between miR-140-5p and OIP5-AS1 or UBR5 was predicted by Starbasev2.0 and TargetScan, and verified using Dual-luciferase reporter assays and RNA pull-down assay. A xenograft mice model was used to evaluate the effects of OIP5-AS1 on tumor growth in vivo. OIP5-AS1 was upregulated in GC cancer and cells. OIP5-AS1 knockdown inhibited cell proliferation, migration, invasion, but induced cell apoptosis in GC. In mechanism, OIP5-AS1 might serve as a sponge for miR-140-5p to enhance UBR5 expression. Moreover, overexpression of miR-140-5p or UBR5 partly reversed the effects of OIP5-AS1 depletion on the progression of GC cells. Furthermore, OIP5-AS1 depletion also suppressed tumor growth in vivo. OIP5-AS1 silencing might suppress proliferation, migration, invasion, and induced apoptosis in GC cells by regulating the miR-140-5p/UBR5 axis.

Spotlight on NLRP6 and Tumor Research Situation: A Potential Cancer Participant

NOD-like receptor family pyrin domain containing 6 (NLRP6) is a new pattern recognition receptor in the mammalian innate immune system. Both the liver and the gut exhibit substantial levels of cytoplasmic expression. It can speed up cell response to endogenous danger signals or exogenous pathogen infection. NLRP6 can function in various ways as an inflammasome or a noninflammasome. The understanding of NLRP6 is steadily increasing thanks to ongoing investigations, but due to discrepancies in how those studies have described their link with tumors, the significance of NLRP6 in the emergence of cancer is still debatable as of this writing. This article will use the structure and function of NLRP6 as the pivotal point and thoroughly explain the present interactions between NLRP6 and tumors and any possible clinical benefits.

LncRNA OIP5-AS1 Knockdown Targets miR-183-5p/GLUL Axis and Inhibits Cell Proliferation, Migration and Metastasis in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is often associated with the infection of Epstein-Barr virus in nasopharynx and is mainly happened in South China and Southeast Asia. Recently, noncoding RNAs have been reported to regulate NPC carcinogenesis. LncRNA OIP5-AS1 participates in tumorigenesis and progression; however, the inherent mechanism of OIP5-AS1-mediated progression of NPC is unclear. In the current study, we aimed to explore the role of OIP5-AS1 in NPC progression. We measured the cell viability, apoptosis, migration, and invasion in NPC cells after OIP5-AS1 modulation. Moreover, we determined whether OIP5-AS1 exerts its oncogenic functions via sponging miR-183-5p in NPC. Furthermore, we determined whether glutamate ammonia ligase (GLUL) was a downstream target of miR-183-5p. We found that OIP5-AS1 downregulation inhibited the viability, migration and invasion of NPC via targeting miR-183-5p. We also identified that GLUL might be a potential downstream target of miR-183-5p in NPC cells. Mechanistically, OIP5-AS1 promotes cell motility via regulating miR-183-5p and GLUL in NPC cells. We concluded that OIP5-AS1 performed its biological functions via targeting miR-183-5p and GLUL in NPC cells.

Physiological and pathophysiological functions of NLRP6: pro- and anti-inflammatory roles

The nucleotide-binding oligomerization and leucine-rich repeat receptor (NLR) protein family consists of important immune sensors that form inflammasomes, a cytosolic multi-protein platform that induces caspase-1 activation and is involved in different inflammatory pathologies. The NLR family pyrin domain containing 6 (NLRP6) is a receptor that can signal by forming inflammasomes, but which can also play an important role without forming inflammasomes. NLRP6 regulates intestinal homeostasis and inflammation, but also is involved in cancer, the nervous system or liver diseases, with both protective and deleterious consequences. In the present article, we review the different roles of NLRP6 in these processes and offer new insights into NLRP6 activation.

This review discusses emerging roles for the NLR family pyrin domain containing 6 receptor (NLRP6) in intestinal homeostasis, inflammation, cancer, the nervous system and liver disease.

A nomogram based on a three pyroptosis gene model and clinical parameters for predicting prognosis of hepatocellular carcinoma

Globally, hepatocellular carcinoma (HCC) has a dismal prognosis and studies have shown that accurate prognostic risk assessment can have clinically significant benefits for patients with HCC patients. After successively performing univariate Cox regression, Lasso regression, and stepwise multivariate Cox regression analysis, three pyroptosis gene (GPX4, NLRP1, and NLRP6) were selected to construct and validate the prognostic model of HCC based on public data. The expression pattern and prognostic implication of GPX4 in HCC was validated by immunohistochemistry staining in HCC specimens collected from Affiliated Hospital of Jining Medical University. A nomogram combined model and clinical characteristics was plotted after the prognostic predictive value of model was validated with receiver operating characteristic curves and Kaplan-Meier survival analysis. Our results indicate that assessing pyroptosis gene expression may be useful to predict the prognosis of HCC patients by enhancing antitumor immunity.

The role of lncRNA OIP5-AS1 in cancer development and progression

OIP5-AS1, a conserved lncRNA, has been reported to be involved in several biological and pathological processes, including oncogenesis. OIP5-AS1 exerts its oncogenic or antitumor functions via regulation of different miRNAs in various cancer types. In this review, we describe the dysregulation of OIP5-AS1 expression in a variety of human cancers. Moreover, we discuss the multiple functions of OIP5-AS1 in cancer, including in proliferation, apoptosis, autophagy, ferroptosis, cell cycle, migration, metastasis, invasion, epithelial to mesenchymal transition, angiogenesis, cancer stem cells and drug resistance. Furthermore, we provide a future perspective for OIP5-AS1 research. We conclude that targeting OIP5-AS1 might be a promising cancer therapy approach.

Long non-coding RNA OIP5-AS1 suppresses microRNA-92a to augment proliferation and metastasis of ovarian cancer cells through upregulating ITGA6

OBJECTIVE

Recently, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been identified as essential biomarkers during development of malignancies. This study was performed to study the roles of lncRNA opa-interacting protein 5 antisense transcript 1 (OIP5-AS1) and miR-92a in ovarian cancer (OC).

METHODS

OIP5-AS1, miR-92a and integrin alpha 6 (ITGA6) expression in OC tissues and cells was assessed. The screened OC cells were respectively with OIP5-AS1-, miR-92a- and ITGA6-related vectors or oligonucleotides . The viability, migration, invasion and apoptosis of the cells were determined and the levels of epithelial-mesenchymal transition (EMT)-related proteins were also measured. The interactions between OIP5-AS1 and miR-92a, and between miR-92a and ITGA6 were confirmed.

RESULTS

OIP5-AS1 and ITGA6 were upregulated while miR-92a was downregulated in OC. Inhibited OIP5-AS1 or downregulated ITGA6 or elevated miR-92a repressed EMT, viability, migration and invasion, and promoted apoptosis of OC cells. OIP5-AS1 as a competing endogenous RNA interacted with miR-92a to regulate ITGA6. These effects that induced by silenced OIP5-AS1 could be reversed by miR-92a inhibition while those that induced by up-regulated miR-92a were reduced by restored ITGA6.

CONCLUSION

OIP5-AS1 silencing promoted miR-92a to repress proliferation and metastasis of OC cells through inhibiting ITGA6.

Long non-coding RNA OIP5-AS1 (Cyrano): A context-specific regulator of normal and disease processes

Long non-coding (lnc) RNAs have been implicated in a plethora of normal biological functions, and have also emerged as key molecules in various disease processes. OIP5-AS1, also commonly known by the alias Cyrano, is a lncRNA that displays broad expression across multiple tissues, with significant enrichment in particular contexts including within the nervous system and skeletal muscle. Thus far, this multifaceted lncRNA has been found to have regulatory functions in normal cellular processes including cell proliferation and survival, as well as in the development and progression of a myriad disease states. These widespread effects on normal and disease states have been found to be mediated through context-specific intermolecular interactions with dozens of miRNAs and proteins identified to date. This review explores recent studies to highlight OIP5-AS1's contextual yet pleiotropic roles in normal homeostatic functions as well as disease oetiology and progression, which may influence its utility in the generation of future theranostics.

The Molecular Roles and Clinical Implications of Non-Coding RNAs in Gastric Cancer

Gastric cancer (GC) is one of the most common malignancies in the world. It is also the fifth most common cancer in China. In recent years, a large number of studies have proved that non-coding RNAs (ncRNAs) can regulate cell proliferation, invasion, metastasis, apoptosis, and angiogenesis. NcRNAs also influence the therapeutic resistance of gastric cancer. NcRNAs mainly consist of miRNAs, lncRNAs and circRNAs. In this paper, we summarized ncRNAs as biomarkers and therapeutic targets for gastric cancer, and also reviewed their role in clinical trials and diagnosis. We sum up different ncRNAs and related moleculars and signaling pathway in gastric cancer, like Bcl-2, PTEN, Wnt signaling. In addition, the potential clinical application of ncRNAs in overcoming chemotherapy and radiotherapy resistance in GC in the future were also focused on.

Downregulation of LncRNA OIP5-AS1 Induced by IL-1β Aggravates Osteoarthritis via Regulating miR-29b-3p/PGRN

BACKGROUND

Long noncoding RNA (lncRNA) OIP5 antisense RNA 1 (OIP5-AS1) is an oncogenic lncRNA; however, its role in osteoarthritis (OA) pathology still remains unknown.

MATERIALS AND METHODS

qRT-PCR was performed to measure the expressions of OIP5-AS1, miR-29b-3p and progranulin (PGRN) mRNA in OA cartilage tissues and normal cartilage tissues. Chondrocyte cell lines, CHON-001 and ATDC5, were treated with different doses of interleukin-1β (IL-1β) to induce the inflammatory response. Overexpression plasmids, microRNA mimics, microRNA inhibitors and small interfering RNAs were constructed and transfected into CHON-001 and ATDC5 cells. CCK-8 assay was used for determining the cell viability and Transwell assay was used for monitoring cell migration. Western blot was applied to measure the expressions of apoptosis-related proteins. Enzyme-linked immunosorbent assay (ELISA) was adopted to measure the contents of inflammatory factors. StarBase and TargetScan were used to predict the binding sites between OIP5-AS1 and miR-29b-3p, miR-29b-3p and 3'-UTR of PGRN respectively, which were verified by dual luciferase reporter assay.

RESULTS

OIP5-AS1 and PGRN mRNA were downregulated while miR-29b-3p was upregulated in OA tissues and models. The up-regulated OIP5-AS1 facilitated the proliferation and migration of CHON-001 and ATDC5 cells, while ameliorated the apoptosis and inflammatory response. However, miR-29b-3p had opposite effects. PGRN was identified as a target gene of miR-29b-3p, which could be indirectly suppressed by OIP5-AS1 knockdown.

CONCLUSION

Downregulation of OIP5-AS1 induced by IL-1β could inhibit the proliferation and migration abilities of CHON-001 and ATDC5 cells and facilitate the apoptosis and inflammation response via regulating miR-29b-3p/PGRN axis.

Autophagy and gastrointestinal cancers: the behind the scenes role of long non-coding RNAs in initiation, progression, and treatment resistance

Gastrointestinal (GI) cancers comprise a heterogeneous group of complex disorders that affect different organs, including esophagus, stomach, gallbladder, liver, biliary tract, pancreas, small intestine, colon, rectum, and anus. Recently, an explosion in nucleic acid-based technologies has led to the discovery of long non-coding RNAs (lncRNAs) that have been found to possess unique regulatory functions. This class of RNAs is >200 nucleotides in length, and is characterized by their lack of protein coding. LncRNAs exert regulatory effects in GI cancer development by affecting different functions such as the proliferation and metastasis of cancer cells, apoptosis, glycolysis and angiogenesis. Over the past few decades, considerable evidence has revealed the important role of autophagy in both GI cancer progression and suppression. In addition, recent studies have confirmed a significant correlation between lncRNAs and the regulation of autophagy. In this review, we summarize how lncRNAs play a behind the scenes role in the pathogenesis of GI cancers through regulation of autophagy.

METTL14 promotes tumorigenesis by regulating lncRNA OIP5-AS1/miR-98/ADAMTS8 signaling in papillary thyroid cancer

Background

Papillary thyroid cancer (PTC) is the most common type of cancer of the endocrine system. Long noncoding RNAs (lncRNAs) are emerging as a novel class of gene expression regulators associated with tumorigenesis. Through preexisting databases available for differentially expressed lncRNAs in PTC, we uncovered that lncRNA OIP5-AS1 was significantly upregulated in PTC tissues. However, the function and the underlying mechanism of OIP5-AS1 in PTC are poorly understood.

Methods

Expression of lncRNA OIP5-AS1 and miR-98 in PTC tissue and cells were measured by quantitative real-time PCR (qRT-PCR). And expression of METTL14 and ADAMTS8 in PTC tissue and cells were measured by qRT-PCR and western blot. The biological functions of METTL14, OIP5-AS1, and ADAMTS8 were examined using MTT, colony formation, transwell, and wound healing assays in PTC cells. The relationship between METTL14 and OIP5-AS1 were evaluated using RNA immunoprecipitation (RIP) and RNA pull down assay. And the relationship between miR-98 and ADAMTS8 were examined by luciferase reporter assay. For in vivo experiments, a xenograft model was used to investigate the effects of OIP5-AS1 and ADAMTS8 in PTC.

Results

Functional validation revealed that OIP5-AS1 overexpression promotes PTC cell proliferation, migration/invasion in vitro and in vivo, while OIP5-AS1 knockdown shows an opposite effect. Mechanistically, OIP5-AS1 acts as a target of miR-98, which activates ADAMTS8. OIP5-AS1 promotes PTC cell progression through miR-98/ADAMTS8 and EGFR, MEK/ERK pathways. Furthermore, RIP and RNA pull down assays identified OIP5-AS1 as the downstream target of METTL14. Overexpression of METTL14 suppresses PTC cell proliferation and migration/invasion through inhibiting OIP5-AS1 expression and regulating EGFR, MEK/ERK pathways.

Conclusions

Collectively, our findings demonstrate that OIP5-AS1 is a METTL14-regulated lncRNA that plays an important role in PTC progression and offers new insights into the regulatory mechanisms underlying PTC development.

Molecular Mechanism of circRAPGEF5 in Regulating the Molecular Axis of microRNA-4712-5p/Tyrosine 3-Monooxygenase/Tryptophan 5-Monooxygenase Activation Protein Epsilon Affecting Cellular Proliferation and Apoptosis in Mammary Cancer

To understand the molecular mechanism of circRAPGEF5, its effect on the proliferation and apoptosis of mammary cancer cells, and its regulatory effect on the molecular axis of miRNA-4712-5p/YWHAE. qRT-PCR and Western blot were used to test circRAPGEF5, miRNA-4712-5p, and YWHAE expression in mammary cancer and paracancerous tissues. The human mammary cancer cell, MDA-MB-231, was cultured in vitro, and pcDNA-NC, pcDNA-circRAPGEF5, anti-miRNA-NC, anti-miRNA-4712-5p, pcDNA-circRAPGEF5, and miRNA-NC, pcDNA-circRAPGEF5 were transfected into MDA-MB-231 cells with miRNA-4712-5p mimics. qRT-PCR and Western blot were employed to detect circRAPGEF5, miRNA-4712-5p, and YWHAE expression in cells. The CCK-8 methodand plate clone formation experiment were conducted to test cellular proliferation ability. Flow cytometry was performed to detect apoptosis rate. Dual luciferase reporter assays were used to test the targeting association between circRAPGEF5 and miRNA-4712-5p, and the targeting association between miRNA-4712-5p and YWHAE. Western blot was utilized to detect Bcl-2, Bax, and Cleared Caspase-3 protein expression. In comparison with paracancerous tissues, circRAPGEF5 and YWHAE expression levels in mammary cancer tissues were significantly reduced (P < 0.05), and miRNA-4712-5p expression levels were significantly increased (P < 0.05). Transfection of pcDNA-circRAPGEF5 or trans-anti-miRNA-4712-5p could reduce the optical density (OD) value, Bcl-2 protein level and clonal formation number to a significant extent (P < 0.05), and it increases Bax and Cleaved Caspase-3 apoptosis rate and protein levels (P < 0.05). Dual luciferase reporter assays confirmed that there was target binding between circRAPGEF5 and miRNA-4712-5p and between miRNA-4712-5p and YWHAE. Co-transfection of pcDNA-circRAP GEF5 and miRNA-4712-5p could greatly reduce transfection of pcDNA-circRAP GEF5 and its effect on the proliferation and apoptosis of MDA-MB-231 cells. Overexpression of circRAPGEF5 can inhibit the proliferation of mammary cancer cells and induce apoptosis by regulating the molecular axis of miRNA-4712-5p/YWHAE.

LncRNA OIP5-AS1 accelerates ox-LDL-treated HUVECs injury by NF-κB pathway via miR-30c-5p

BACKGROUND

Oxidized low-density lipoprotein (ox-LDL) could induce endothelial injury and played a vital role in the progression and development of atherosclerosis. This study aimed to investigate the role of Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) in ox-LDL-induced human umbilical vascular endothelial cells (HUVECs) injury and the potential mechanisms.

METHODS

Cell proliferation and apoptosis were evaluated by Cell Counting Kit-8 (CCK-8) assay and flow cytometry assay, respectively. The levels of lactate dehydrogenase (LDH), reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide (NO) were detected by corresponding detection kits, respectively. Quantitative real-time PCR (qRT-PCR) was conducted to measure the expression of OIP5-AS1 or microRNA-30c-5p (miR-30c-5p) in HUVECs. Binding between OIP5-AS1 and miR-30c-5p was predicted through bioinformatics analysis and confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP). Western blot was used to analyze p-IκB, IκB, p-p65 and p65 levels.

RESULTS

In HUVECs, exposure to ox-LDL led to a decrease in cell viability and an increase in LDH release and apoptosis with concomitant enhancement of oxidative stress, as evidenced by increased ROS and MDA generation, as well as decreased SOD activity and NO levels, while OIP5-AS1 knockdown or miR-30c-5p upregulation could rescue these effects above. Mechanically, OIP5-AS1 functioned as a sponge of miR-30c-5p. OIP5-AS1-induced injury and apoptosis, oxidative stress and activation of NF-κB pathway were reversed by miR-30c-5p in ox-LDL-treated HUVECs.

CONCLUSION

OIP5-AS1 contributed to ox-LDL-treated HUVECs injury by activation of NF-κB pathway via miR-30c-5p.

Long non‑coding RNA OIP5‑AS1 facilitates the progression of ovarian cancer via the miR‑128‑3p/CCNG1 axis

Long non‑coding RNA (LncRNA) o‑phthalaldehyde-interacting protein 5 antisense transcript 1 (OIP5‑AS1) serves major roles in the progression of various types of cancer. The present study investigated its biological function in ovarian cancer (OC) and its mechanisms. The levels of OIP5‑AS1, microRNA‑128‑3p (miR‑128‑3p) and cyclin G1 (CCNG1) were examined by reverse transcription‑quantitative PCR. Cell viability, apoptosis, migration and invasion were detected to analyze cellular progression. Glycolytic metabolism was assessed by detecting the levels of glucose consumption and lactate production. CCNG1 and hexokinase 2 protein levels were measured by western blotting. Dual‑luciferase reporter assay, RNA immunoprecipitation and RNA pull‑down assays were performed to affirm the interaction between two molecules. OIP5‑AS1 was found to be upregulated in OC tissues and cells. Knockdown of OIP5‑AS1 suppressed cell viability, migration, invasion and glycolysis while promoting apoptosis in OC cells. OIP5‑AS1 interacted with miR‑128‑3p and functioned as an oncogene by sequestering miR‑128‑3p. In addition, CCNG1 was a target gene for miR‑128‑3p and miR‑128‑3p regulated the CCNG1‑induced effects on OC cells by downregulating CCNG1. OIP5‑AS1 upregulated the expression of CCNG1 via targeting miR‑128‑3p. OIP5‑AS1 knockdown also inhibited tumor growth of OC in vivo by modulating the expression of miR‑128‑3p and CCNG1. Collectively, these data illustrated that the oncogenic role of OIP5‑AS1 in OC was associated with the miR‑128‑3p/CCNG1 axis at least in part. OIP5‑AS1 might be a probable diagnostic and therapeutic biomarker for the treatment of OC patients.

Silencing of OIP5-AS1 Protects Endothelial Cells From ox-LDL-Triggered Injury by Regulating KLF5 Expression via Sponging miR-135a-5p

Background: Long non-coding RNAs (lncRNAs) have been implicated in the pathogenesis of atherosclerosis. LncRNA OIP5 antisense RNA 1 (OIP5-AS1) has been found to be associated with the development of atherosclerosis. In this study, we further investigated the molecular basis of OIP5-AS1 in atherosclerosis pathogenesis.

Methods: Oxidative low-density lipoprotein (ox-LDL) was used to treat human umbilical vein endothelial cells (HUVECs). The levels of OIP5-AS1, miR-135a-5p, and Krüppel-like factor 5 (KLF5) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell viability, migration, and apoptosis were evaluated using the Cell Counting Kit-8 (CCK-8), Transwell, and flow cytometry, respectively. The levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and malondialdehyde (MDA) were determined with enzyme-linked immunosorbent assay (ELISA). Targeted interactions among OIP5-AS1, miR-135a-5p, and KLF5 were confirmed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Animal studies were performed to assess the role of OIP5-AS1 in atherosclerosis progression in vivo.

Results: Our data showed the significant upregulation of OIP5-AS1 in atherosclerosis serum and ox-LDL-stimulated HUVECs. The silencing of OIP5-AS1 protected against ox-LDL-triggered cytotoxicity in HUVECs and diminished lipids secretion in ApoE^−/− mice. Moreover, OIP5-AS1 functioned as a molecular sponge of miR-135a-5p, and miR-135a-5p was a functional mediator of OIP5-AS1 in regulating ox-LDL-induced HUVEC injury. KLF5 was a direct target of miR-135a-5p, and the increased expression of miR-135a-5p alleviated ox-LDL-induced cytotoxicity by downregulating KLF5. Furthermore, OIP5-AS1 influenced KLF5 expression through sponging miR-135a-5p.

Conclusion: The current work identified that the silencing of OIP5-AS1 protected against ox-LDL-triggered cytotoxicity in HUVECs at least in part by influencing KLF5 expression via acting as a miR-135a-5p sponge.

A review on the role of oncogenic lncRNA OIP5-AS1 in human malignancies

OIP5-AS1 is a long non-coding transcript with high expression in nervous system, but crucial functions in the neoplastic transformation. This lncRNA partake in the regulation of cell cycle transition at different points. Moreover, it acts a competing endogenous RNA for tens of microRNAs among them are miR-338-3p, miR-204-5p, miR-641, miR-422a, miR-367-3p, miR-153-3p, miR-186, miR-369-3p, miR-137, miR-342-3p, miR‑429, miR-3163, miR-363-3p, miR-186a-5p, hsa-miR-26a-3p, miR‑300, miR-217, miR-378a-3p and miR-448. OIP5-AS1 influence the carcinogenesis via different routes among them is modulation of epithelial-mesenchymal transition. Expression of OIP5-AS1 has been elevated in nearly all kinds of neoplastic tissues except for multiple myeloma. Moreover, in bladder, gastric cancer and lung cancers, assessment of its expression in clinical samples has led to conflicting results. In the current paper, we have provided a comprehensive collection of research papers that evaluated function of OIP5-AS1 in diverse cancer types.

Inflammasomes in cancer: Effect of epigenetic and autophagic modulations

Tumour-promoting inflammation is a critical hallmark in cancer development, and inflammasomes are well-known regulators of inflammatory processes within the tumour microenvironment. Different inflammasome components along with the adaptor, apoptosis-associated speck-like protein containing caspase activation and recruitment domain (ASC), and the effector, caspase-1, have a significant influence on tumorigenesis but in a tissue-specific and stage-dependent manner. The downstream products of inflammasome activation, that is the proinflammatory cytokines such as IL-1β and IL-18, regulate tissue homeostasis and induce antitumour immune responses, but in contrast, they can also favour cancer growth and proliferation by directing various oncogenic signalling pathways in cancer cells. Moreover, different epigenetic mechanisms, including DNA methylation, histone modification and noncoding RNAs, control inflammasomes and their components by regulating gene expression during cancer progression. Furthermore, autophagy, a master controller of cellular homeostasis, targets inflammasome-induced carcinogenesis by maintaining cellular homeostasis and removing potential cancer risk factors that promote inflammasome activation in support of tumorigenesis. Here, in this review, we summarize the effect of inflammasome activation in cancers and discuss the role of epigenetic and autophagic regulatory mechanisms in controlling inflammasomes. A proper understanding of the interactions among these key processes will be useful for developing novel therapeutic regimens for targeting inflammasomes in cancer.

NLRP6 exerts a protective role via NF-kB with involvement of CCL20 in a mouse model of alcoholic hepatitis

Alcoholic hepatitis (AH) is an important form of alcoholic liver disease (ALD), and its incidence is continuously increasing leading to advanced disease burden. The NOD-like receptors (NLRs) are a specialized group of intracellular pattern recognition receptors, which participate in inflammatory diseases. However, the role of NLRs in the pathogenesis of AH still remain obscure. The animal model of alcoholic hepatitis in mice was established according to National Institute on Alcohol Abuse and Alcoholism (NIAAA) method. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze the expression of NLR family members in liver tissues of the ethanol-fed(EtOH-fed)group and pair-fed group. NLRP6 was overexpressed in mice by injecting Recombinant Adeno-Associated Virus into the tail vein. Mouse Cytokines and Chemokines RT² Profiler PCR Array was used to analyze the related cytokines and chemokines involved in the development of alcoholic hepatitis. Among the NLR family members, the expression of NLRP6 decreased most significantly in the animal model of AH. Our results demonstrated that overexpression of NLRP6 in vivo obviously alleviated steatosis, inflammation and fibrosis in liver. Meanwhile, the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in mice also decreased. Besides, Chemokine (C-C motif) ligand 20(CCL20) was one of the most significantly up-regulated chemokines in the mouse AH model and CCL20 was participated in NLRP6-mediated AH. NLRP6 could inhibit the activation of nuclear factor (NF)-κB signaling pathway in vitro and in vivo. Furthermore, the activation, proliferation, and migration of hepatic stellate cells was enhanced after downregulation of NLRP6. In summary, NLRP6 may play a protective role in the development of AH. NLRP6 could inhibit activation of NF-κB signaling pathway in AH.

Long Non-Coding RNA OIP5-AS1 Knockdown Enhances CDDP Sensitivity in Osteosarcoma via miR-377-3p/FOSL2 Axis

Background

Drug resistance is one of big obstacles for the treatment of tumor. Long non-coding RNA Opa-interacting protein 5-antisense RNA 1 (OIP5-AS1) was identified to involve in drug resistance. In this research, the effects of OIP5-AS1 on cisplatin (CDDP) resistance in osteosarcoma (OS) were mainly investigated.

Methods

The levels of OIP5-AS1, microRNA-377-3p (miR-377-3p), and FOS like 2 (FOSL2) were measured by quantitative real-time polymerase chain reaction. The inhibitory concentration 50 (IC₅₀) value of CDDP, cell viability and apoptotic rate was evaluated through Cell Counting Kit-8 and flow cytometry assays, respectively. The levels of multidrug resistance-associated protein 1 (MRP1), P-glycoprotein, B-cell lymphoma 2, Bcl2-associated X, cleaved-caspase-3, and FOSL2 were detected by Western blot assay. The interaction between miR-377-3p and OIP5-AS1 or FOSL2 was verified by Dual-Luciferase Reporter and RNA Immunoprecipitation assays. The function of OIP5-AS1 was detected by a xenograft tumor model in vivo.

Results

OIP5-AS1 and FOSL2 were up-regulated, while miR-377-3p was down-regulated in CDDP-resistant OS tissues and cells. OIP5-AS1 silencing inhibited cell viability and the IC₅₀ value of CDDP, and promoted apoptotic rate in CDDP-resistant OS cells. Mechanically, OIP5-AS1 was verified as a sponge to miR-377-3p and FOSL2 was a target of miR-377-3p. Moreover, OIP5-AS1 knockdown repressed OS tumor growth and enhanced CDDP sensitivity of OS in vivo.

Conclusion

OIP5-AS1 positively modulated FOSL2 expression to decrease CDDP sensitivity in OS by sponging miR-377-3p.

Long non-coding RNA OIP5-AS1 suppresses multiple myeloma progression by sponging miR-27a-3p to activate TSC1 expression

BACKGROUND

Multiple myeloma (MM) is a prevalent hematological malignancy. Long noncoding RNAs are correlated with the development of MM. In this project, the function of lncRNA opa interacting protein 5-antisense 1 (OIP5-AS1) in MM and the potential mechanistic pathway were explored.

METHODS

The expression of OIP5-AS1, microRNA (miR)-27a-3p and tuberous sclerosis 1 (TSC1) was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) assay. Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) assay, colony formation assay and Bromodeoxyuridine (BrdU) staining. And cell apoptosis was evaluated by flow cytometry assay. Cell metastasis was assessed utilizing transwell assay. Western blot analysis was employed to detect protein level. The target relation between miR-27a-3p and OIP5-AS1 or TSC1 was confirmed via dual-luciferase reporter assay and RNA immunoprecipitation assay. Tumor xenograft assay was conducted to measure the function of OIP5-AS1 in vivo.

RESULTS

The expression levels of OIP5-AS1 and TSC1 were decreased in MM, whereas miR-27a-3p was upregulated. High level of OIP5-AS1 could predict favourable prognosis of MM patients. Overexpression of OIP5-AS1 inhibited cell viability, colony formation ability, migration and invasion, induced cell cycle arrest in G1 phase and apoptosis of MM cells in vitro as well as repressed tumorigenesis in vivo. MiR-27a-3p was a target of OIP5-AS1, and reversed the impact of OIP5-AS1 on MM cells. MiR-27a-3p directly targeted TSC1. Silencing of miR-27a-3p repressed MM progression by elevating TSC1 expression. OIP5-AS1 upregulated TSC1 by sponging miR-27a-3p.

CONCLUSION

OIP5-AS1 repressed multiple myeloma progression by regulating miR-27a-3p/TSC1 axis.

NLRP6 inflammasome

NOD-like receptor family pyrin domain containing 6 (NLRP6) is a novel NLR family member, that shows high expression in the intestine and liver (in contrast to NLRP3 in myeloid cells), to regulate inflammation and host defense against microbes. NLRP6 is reported to involved in inflammasome activation, regulation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling, antiviral interferon (IFN) signaling, mucus secretion, and antimicrobial peptide (AMP) production. Here, we discuss the recent findings as well as debates regarding: how NLRP6 is induced ("signal I″) and activated ("signal II"); its roles in intestinal cells and immune cells; how NLRP6 and NLRP9 coordinate to regulate the anti-viral immune response in the intestine; potential targeting of NLRP6 in human diseases.

Identification of lncRNA-miRNA-mRNA regulatory network associated with primary open angle glaucoma

BACKGROUND

Primary open angle glaucoma (POAG) is a multifactorial disorder characterized by a progressive permanent degeneration of retinal ganglion cell (RGCs) death. An increasing number of studies have suggested that long noncoding RNAs (lncRNAs) have the ability to regulate gene expression; however, thus far, the mechanisms and functions of lncRNAs in the development of POAG are still unclear.

METHODS

Using the data from Gene Expression Omnibus (GEO), differentially expressed lncRNAs and differentially expressed mRNAs between POAG patients and controls were identified. Then, the lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) network was constructed, and the key lncRNAs in POAG were identified. A Gene Ontology (GO) analysis and a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to assess the enriched biological functions of mRNA in the ceRNA network.

RESULTS

During this study, a POAG-related ceRNA network with 37 miRNA nodes, 248 lncRNA nodes, 178 mRNA nodes, and 1985 edges was constructed. In addition, four lncRNAs (DNAJC27-AS1, AF121898, OIP5-AS1, and SNX29P2) were established as hub RNAs in this ceRNA network. The functional assay showed that 18 GO terms and 17 pathways were enriched.

CONCLUSION

This study provides novel insights into the lncRNA-related ceRNA network in POAG, and the four lncRNAs were identified in the development of POAG.

LncRNA OIP5-AS1 interacts with miR-363-3p to contribute to hepatocellular carcinoma progression through up-regulation of SOX4

Long noncoding RNA OIP5-AS1 has been observed to be increased in several cancers, however, its role and biological mechanism was poorly understood in HCC. Currently, we found OIP5-AS1 expression was upregulated in HCC cells compared with normal human liver cells. Knockdown of OIP5-AS1 suppressed HCC cell proliferation, induced cells cycle arrest and cells apoptosis. In addition, HCC cell migration and invasion capacity in vitro were also inhibited by OIP5-AS1 inhibition. Bioinformatics analysis revealed OIP5-AS1 could interact with miR-363-3p, thereby repressing HCC development. We also observed miR-363-3p was significantly decreased in HCC cells and overexpression of miR-363-3p repressed HCC progression. The correlation between OIP5-AS1 and miR-363-3p was confirmed by performing RIP assay and RNA pull-down assay. Subsequently, SOX4 was predicted as a target of miR-363-3p and miR-363-3p modulated SOX4 levels negatively in vitro. Apart from these, in vivo experiments established that OIP5-AS1 can suppress HCC development through regulating miR-363-3p and SOX4. Collectively, these demonstrated that OIP5-AS1 was involved in HCC progression via targeting miR-363-3p and SOX4. OIP5-AS1 can act as a novel candidate for HCC diagnosis, prognosis, and therapy.

Long non-coding RNA OIP5-AS1 serves as an oncogene in laryngeal squamous cell carcinoma by regulating miR-204-5p/ZEB1 axis

Laryngeal squamous cell carcinoma (LSCC) is the most common type of laryngeal cancer with poor prognosis. In the present study, we aimed to investigate the biological role of long non-coding RNA OIP5-AS1 in LSCC. The results demonstrated that the expression levels of OIP5-AS1 were significantly increased in LSCC tissues and cell lines. High expression of OIP5-AS1 was closely correlated with lymph node metastasis and advanced clinical stage of LSCC patients. Moreover, in vitro assays showed that OIP5-AS1 overexpression promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of LSCC cells, whereas OIP5-AS1 knockdown exerted suppressive effects on LSCC cells. Furthermore, OIP5-AS1 was confirmed to serve as a competing endogenous RNA of miR-204-5p in LSCC cells, and restoration of miR-204-5p counteracted the OIP5-AS1-mediated oncogenic effects. In conclusion, our study provides promising evidence that lncRNA OIP5-AS1 functions as a tumor promoter in LSCC and may be used as a potential target for LSCC therapy.