Long noncoding RNA SOX21‐AS1 promotes cervical cancer progression by competitively sponging miR‐7/VDAC1

SOX21-AS1 Augmented Cervical Cancer Growth by Triggering FZD3 to Activate the Wnt/β-Catenin Signaling Pathway

Long non-coding RNA (LncRNA) SOX21-AS1 has been reported that it plays an important role in biological processes of several cancers. However, how it functions in cervical cancer (CC) still remain unclear. This investigation seeks to explore the impact of SOX21-AS1 on CC cell proliferation, invasion and migration and its association to the FZD3 and the Wnt/β-catenin signaling pathway. SOX21-AS1 expression levels were detected using real-time quantitative PCR in 20 cases of cervical cancer together with its adjacent tissues and several cervical cancer cell lines. Transgenic technology and functional experiments were conducted to confirm the carcinogenic properties of SOX21-AS1, and western blot was utilized to analyze the regulatory network composed of SOX21-AS1, FZD3 and the Wnt/β-catenin signaling pathway in CC. Through bioinformatics analysis, we found that the expression of SOX21-AS1 in CC was the highest among 16 kinds of tumor tissues. Moreover, clinical specimens confirmed that both CC tissues and cell lines possessed elevated SOX21-AS1 expressions (P < 0.01). CC cells which stably expressed upregulated SOX21-AS1 were noted to possesses higher rates of metastasis, invasion and proliferation, lower apoptotic rates and higher expression of FZD3,β-catenin and c-myc (P < 0.01). Conversely, the use of small interfering RNA to inhibit the expression of SOX21-AS1 yielded the opposite results (P < 0.01). SOX21-AS1 functions as an oncogenic LncRNA which enhances CC cell metastasis, invasion and proliferation through FZD3 upregulation via Wnt/β-catenin-signaling pathway activation. This LncRNA may represent an important biomarker for CC patients.

RNA-seq analysis identifies transcriptomic profiles associated with anal cancer recurrence among people living with HIV

BACKGROUND

Chemoradiation therapy (CRT) is the standard of care for squamous cell carcinoma of the anus (SCCA), the most common type of anal cancer. However, approximately one fourth of patients still relapse after CRT.

METHODS

We used RNA-sequencing technology to characterize coding and non-coding transcripts in tumor tissues from CRT-treated SCCA patients and compare them between 9 non-recurrent and 3 recurrent cases. RNA was extracted from FFPE tissues. Library preparations for RNA-sequencing were created using SMARTer Stranded Total RNA-Seq Kit. All libraries were pooled and sequenced on a NovaSeq 6000. Function and pathway enrichment analysis was performed with Metascape and enrichment of gene ontology (GO) was performed with Gene Set Enrichment Analysis (GSEA).

RESULTS

There were 449 differentially expressed genes (DEGs) observed (390 mRNA, 12 miRNA, 17 lincRNA and 18 snRNA) between the two groups. We identified a core of upregulated genes (IL4, CD40LG, ICAM2, HLA-I (HLA-A, HLA-C) and HLA-II (HLA-DQA1, HLA-DRB5) in the non-recurrent SCCA tissue enriching to the gene ontology term 'allograft rejection', which suggests a CD4+ T cell driven immune response. Conversely, in the recurrent tissues, keratin (KRT1, 10, 12, 20) and hedgehog signaling pathway (PTCH2) genes involved in 'Epidermis Development,', were significantly upregulated. We identified miR-4316, that inhibit tumor proliferation and migration by repressing vascular endothelial growth factors, as being upregulated in non-recurrent SCCA. On the contrary, lncRNA-SOX21-AS1, implicated in the progression of many other cancers, was also found to be more common in our recurrent compared to non-recurrent SCCA.

Our study identified key host factors which may drive the recurrence of SCCA and warrants further studies to understand the mechanism and evaluate their potential use in personalized treatment.Key MessageOur study used RNA sequencing (RNA-seq) to identify pivotal factors in coding and non-coding transcripts which differentiate between patients at risk for recurrent anal cancer after treatment. There were 449 differentially expressed genes (390 mRNA, 12 miRNA, 17 lincRNA and 18 snRNA) between 9 non-recurrent and 3 recurrent squamous cell carcinoma of anus (SCCA) tissues. The enrichment of genes related to allograft rejection was observed in the non-recurrent SCCA tissues, while the enrichment of genes related to epidermis development was positively linked with recurrent SCCA tissues.

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

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

Long non-coding RNA SOX21-AS1: A potential tumor oncogene in human cancers

Emerging data have proposed that the aberrant level of long noncoding RNAs (lncRNA) is related to the onset and progression of cancer. Among them, lncRNA SOX21-AS1 was shown to upregulate and seem to be a novel oncogene in various cancer, including ovarian cancer, lung cancer, breast cancer, pancreatic cancer, osteosarcoma, and melanoma. Available data indicated that SRY-box transcription factor 21 antisense divergent transcript 1 (SOX21-AS1) mostly acts as a competing endogenous RNA (ceRNA) to inhibit the level of its target microRNAs (miRNAs), leading to upregulation of their targets. In addition, SOX21-AS1 is engaged in various signaling pathways like transforming growth factor-β (TGF-β) signaling, Wnt signaling, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling. Moreover, this lncRNA was revealed to be correlated with the clinicopathological features of affected patients. SOX21-AS1 was also proved to enhance the resistance of ovarian cancer cells to cisplatin chemotherapy. SOX21-AS1 is markedly associated with poor prognosis and low survival of patients, proposing that it may be a prognostic and diagnostic biomarker in cancer. Overexpression of SOX21-AS1 is related to various cancer-related pathways, like epithelial mesenchymal transition (EMT), invasion, migration, apoptosis, and cell cycle arrest. In this work, we aimed to discuss the biogenesis, function, and underlying molecular mechanism of SOX21-AS1 in cancer progression as well as its potential as a prognostic and diagnostic biomarker in human cancers.

LncRNA SOX21-AS1 accelerates endometrial carcinoma progression through the miR-7-5p/RAF1 pathway

BACKGROUND

Endometrial carcinoma (EC) is one of the world's typical female reproductive tract malignancies, mostly occurring in postmenopausal women. Many reports have confirmed that long non-coding RNA SOX21 antisense RNA1 (lncRNA SOX21-AS1) is associated with the progressions of various cancer. However, the mechanism of SOX21-AS1 in EC remains unclear. Our study is intended to probe the mechanisms of SOX21-AS1 on EC progression.

METHODS

The CCK-8 assay and colony formation detected cell proliferation. Cell migration and invasion were assessed by transwell analysis. Apoptosis was measured by flow cytometry assay. Bioinformatics software predicted target binding and confirmed using a luciferase reporter analysis.

RESULTS

SOX21-AS1 expression was upregulated in EC tumor tissues and cells. High expression of SOX21-AS1 was associated with poor overall survival. Silencing of SOX21-AS1 restrained cell proliferation, migration, invasion, and increased apoptosis in HEC-1A and Ishikawa cells. Additionally, bioinformatics analysis demonstrated that SOX21-AS1 modulated RAF1 expression by competitively binding to miR-7-5p. Functionally, silencing of RAF1 reversed the functions of miR-7-5p inhibitor in the proliferation, invasion, and apoptosis of HEC-1A/sh-SOX21-AS1 and Ishikawa/sh-SOX21-AS1 cells.

CONCLUSIONS

SOX21-AS1 promoted the pathological development of EC by regulating the miR-7-5p/RAF1 pathway. This research may provide a novel target for EC therapy.

Retracted: Long noncoding RNA RHPN1-AS1, induced by KDM5B, is involved in breast cancer via sponging miR-6884-5p

The above article, published online in Journal of Cellular Biochemistry on 31 January 2020 in Wiley Online Library (https://doi.org/10.1002/jcb.29645), has been retracted by agreement between the authors, the journal's Editor in Chief, Prof. Dr. Christian Behl, and Wiley Periodicals LLC. The authors asked to retract their article after substantial mistakes in experimental data were found, thus the results are considered to be invalid.

Long non-coding RNAs as promising biomarkers and therapeutic targets in cervical cancer

Cervical cancer is the second most common cancer in women. The detection of oncopathologies in the early stages of development is a paramount task of modern medicine, which can be solved only by improving modern diagnostic methods. The use of screening for certain tumor markers could complement modern tests such as testing for oncogenic types of human papillomavirus (HPV), cytology, colposcopy with acetic acid and iodine solutions. Such highly informative biomarkers can be long noncoding RNAs (lncRNAs) that are highly specific compared to the mRNA profile and are involved in the regulation of gene expression. LncRNAs are a class of non-coding RNAs molecules that are typically over 200 nucleotides in length. LncRNAs may be involved in the regulation of all major cellular processes, including proliferation and differentiation, metabolism, signaling pathways, and apoptosis. LncRNAs molecules are highly stable due to their small size, which is also their undoubted advantage. The study of individual lncRNAs as regulators of the expression of genes involved in the mechanisms of oncogenesis cervical cancer can be not only of great diagnostic value, but, as a result, of therapeutic significance in cervical cancer patients. This review article will present the characteristics of lncRNAs that allow them to be used as accurate diagnostic and prognostic tools, as well as to consider them as effective therapeutic targets in cervical cancer.

Advances in epigenetic modifications and cervical cancer research

Cervical cancer (CC) is an important public health problem for women, and perspectives and information regarding its prevention and treatment are quickly evolving. Human papilloma virus (HPV) has been recognized as a major contributor to CC development; however, HPV infection is not the only cause of CC. Epigenetics refers to changes in gene expression levels caused by non-gene sequence changes. Growing evidence suggests that the disruption of gene expression patterns which were governed by epigenetic modifications can result in cancer, autoimmune diseases, and various other maladies. This article mainly reviews the current research status of epigenetic modifications in CC based on four aspects, respectively DNA methylation, histone modification, noncoding RNA regulation and chromatin regulation, and we also discuss their functions and molecular mechanisms in the occurrence and progression of CC. This review provides new ideas for early screening, risk assessment, molecular targeted therapy and prognostic prediction of CC.

Role of noncoding RNAs with emphasis on long noncoding RNAs as cervical cancer biomarkers

Cervical cancer is a significant public health problem in developing countries, as most cases present at an advanced stage. This review aimed to analyze the role of noncoding RNAs as diagnostic and prognostic biomarkers in cervical cancers. Published studies on specific microRNA signatures in body fluids and cervical cancer tissues are highly heterogeneous, and there are no validated assays. The precision of the various immune-associated long noncoding (lncRNA) signatures should be assessed in clinical samples. Even though lncRNAs are tissue and cancer-specific, safe and appropriate methods for delivery to tumor tissues, toxicities and side effects are to be explored. Few studies have evaluated deregulated lncRNA expression levels with clinicopathological factors in a limited number of clinical samples. Prospective studies assessing the diagnostic and prognostic roles of circulating lncRNAs and P-Element-induced wimpy testis interacting PIWI RNAs (Piwil RNAs) in cervical cancer cases are essential. For the clinical application of lnc-RNA-based biomarkers, comprehensive research is needed as the impact of noncoding transcripts on molecular pathways is complex. The standardization and validation of deregulated ncRNAs in noninvasive samples of cervical cancer cases are needed.

Comprehensive analysis of cuproptosis-related lncRNAs model in tumor immune microenvironment and prognostic value of cervical cancer

Cervical cancer (CC) is the fourth leading gynecological malignancy in females worldwide. Cuproptosis, a form of cell death induced by copper, elicits a novel therapeutic strategy in anticancer therapy. Nonetheless, the effects of cuproptosis-related lncRNAs in CC remain unclear. Therefore, we aim to investigate cuproptosis-related lncRNAs, develop a risk model for prognostic prediction, and elucidate the immunological profile of CC. Transcription profiles and clinical follow-up data of CC were retrieved from The Cancer Genome Atlas (TCGA) database. Afterward, the risk model was built by distinguishing prognostic cuproptosis-related lncRNAs using the least absolute shrinkage and selection operator (LASSO) Cox regression. The correctness of the risk model was validated, and a nomogram was established followed by tumor immune microenvironment analysis. Tumor immune dysfunction and exclusion (TIDE) scores were used to assess immunotherapy response, and anticancer pharmaceutical half-maximal inhibitory concentration (IC50) prediction was performed for potential chemotherapy medicines. Finally, through coexpression analysis, 199 cuproptosis-related lncRNAs were collected. A unique risk model was generated using 6 selected prognostic cuproptosis-related lncRNAs. The risk score performed a reliable independent prediction of CC survival with higher diagnostic effectiveness compared to generic clinical characteristics. Immunological cell infiltration investigation indicated that the risk model was substantially linked with CC patients’ immunology, and the low-risk patients had lower TIDE scores and increased checkpoint expression, suggesting a stronger immunotherapy response. Besides, the high-risk group exhibited distinct sensitivity to anticancer medications. The immune-related progression was connected to the differentially expressed genes (DEGs) between risk groups. Generally, the risk model comprised 6 cuproptosis-related lncRNAs that may help predict CC patients’ overall survival, indicate immunocyte infiltration, and identify individualized treatment.

Long-noncoding RNAs as epigenetic regulators in neurodegenerative diseases

The growing and rapid development of high-throughput sequencing technologies have allowed a greater understanding of the mechanisms underlying gene expression regulation. Editing the epigenome and epitranscriptome directs the fate of the transcript influencing the functional outcome of each mRNA. In this context, non-coding RNAs play a decisive role in addressing the expression regulation at the gene and chromosomal levels. Long-noncoding RNAs, consisting of more than 200 nucleotides, have been shown to act as epigenetic regulators in several key molecular processes involving neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and Huntington's disease. Long-noncoding RNAs are abundantly expressed in the central nervous system, suggesting that their deregulation could trigger neuronal degeneration through RNA modifications. The evaluation of their diagnostic significance and therapeutic potential could lead to new treatments for these diseases for which there is no cure.

Downregulation of SOX21-AS1 alleviated cisplatin resistance in cervical cancer through Epithelial-messenchymal transition (EMT) inhibition

Cisplatin is widely used in chemotherapies in cervical cancer (CC). Nevertheless, drug resistance in cancer patients poses a major threat to efficacy of treatment. To explore the underlying modulatory mechanism of SOX21-AS1 in cisplatin resistance in CC cell and mice models，Gepia database was referred for SOX21-AS1 expression in cancer tissues and normal ones. RT-qPCR was used to measure the differential expression of SOX21-AS1 in parental Siha cells and cisplatin-resistant Siha/DDP cells. Luciferase reporter gene assays were conducted to verify putative bindings between SOX21-AS1 and miR-9-3p. Western blot method was employed to evaluate the changes in cleaved-caspase 7 protein expression. Cisplatin resistance was evaluated in each transfected group using CCK8 method after cells were exposed to cisplatin (0,7.5,15,30,60,120, 240ug/ml) for 24h. Flow cytometry method was used to measure the apoptosis rates. Cell migration and invasion were measured using Transwell assays. Immunofluorescence method was applied to observe EMT markers including E-cadherin, Snail, MMP3 and MMP9. Siha/DDP cell groups stably transfected with sh-NC and sh- SOX21-AS1 were injected through tail vein of Balb/C mice. Lung tissue sections were used for HE staining and IHC analysis. SOX1-AS1 expression was higher in cancer tissues than normal ones and was also higher in Siha/DDP rather than Siha cells. SOX21-AS1 was targeted by miR-9-3p in CC cells. Downregulation of SOX21-AS1 or overexpression of miR-9-3p inhibited cisplatin resistance in Siha/DDP cells and reduced cell invasion and migration and attenuated EMT progression. In vivo, the SOX21-AS1 knockdown led to less severe lung metastasis. Downregulation of SOX21-AS1 alleviated cisplatin resistance in cervical cancer through EMT inhibition.

MicroRNAs as Regulators of Cancer Cell Energy Metabolism

To adapt to the tumor environment or to escape chemotherapy, cancer cells rapidly reprogram their metabolism. The hallmark biochemical phenotype of cancer cells is the shift in metabolic reprogramming towards aerobic glycolysis. It was thought that this metabolic shift to glycolysis alone was sufficient for cancer cells to meet their heightened energy and metabolic demands for proliferation and survival. Recent studies, however, show that cancer cells rely on glutamine, lipid, and mitochondrial metabolism for energy. Oncogenes and scavenging pathways control many of these metabolic changes, and several metabolic and tumorigenic pathways are post-transcriptionally regulated by microRNA (miRNAs). Genes that are directly or indirectly responsible for energy production in cells are either negatively or positively regulated by miRNAs. Therefore, some miRNAs play an oncogenic role by regulating the metabolic shift that occurs in cancer cells. Additionally, miRNAs can regulate mitochondrial calcium stores and energy metabolism, thus promoting cancer cell survival, cell growth, and metastasis. In the electron transport chain (ETC), miRNAs enhance the activity of apoptosis-inducing factor (AIF) and cytochrome c, and these apoptosome proteins are directed towards the ETC rather than to the apoptotic pathway. This review will highlight how miRNAs regulate the enzymes, signaling pathways, and transcription factors of cancer cell metabolism and mitochondrial calcium import/export pathways. The review will also focus on the metabolic reprogramming of cancer cells to promote survival, proliferation, growth, and metastasis with an emphasis on the therapeutic potential of miRNAs for cancer treatment.

LncRNA LOXL1-AS1 Facilitates the Oncogenic Character in Cervical Cancer by the miR-526b-5p /LYPLA1 Axis

Increasing reports demonstrate that long noncoding RNAs participate in the regulation of numerous malignancies, cervical cancer included. Although lncRNA LOXL1 antisense RNA 1 has been commonly accepted to be an oncogene in many cancers. Here, the role of LOXL1-AS1 in CC still need to be explored. In this study, LOXL1-AS1 was found elevated in CC tissues and cells. LOXL1-AS1 depletion restrained CC cell proliferation, migration, invasion, and angiogenesis in vivo. Furthermore, we found that LOXL1-AS1 upregulated Lysophospholipase 1 expression via sequestering miR-526b-5p. Rescue assays revealed that overexpression of LYPLA1 reversed the LOXL1-AS1 silencing-induced inhibitory effects on the malignant phenotypes of CC cells. To conclude, this study showed that LOXL1-AS1 facilitates cellular process in CC via functioning as a miR-526b-5p sponge.

A four immune-related long noncoding RNAs signature as predictors for cervical cancer

The progression, metastasis, and prognosis of cervical cancer (CC) is influenced by the tumor immune microenvironment. Studies proved that long non-coding RNAs (lncRNAs) to engage in cervical cancer development, especially immune-related lncRNAs, have emerged crucial in the tumor immune process. This study was set out to identify an immune-related lncRNA signature. In total, 13,838 lncRNA expression profiles and 328 immune genes were acquired from the clnical data of 306 CC tissues and 3 non-CC tissues. From the 433 identified immune-related lncRNAs, 4 candidate immune-related lncRNAs (SOX21-AS1, AC005332.4, NCK1-DT, LINC01871) were considered independent indicators of cervical cancer prognosis through the univariate and multivariate Cox regression analysis, and they were used to construct a prognostic and survival lncRNA signature model followed by the bootstrap method for further verification. Kaplan-Meier curves illustrated that cervical cancer patients could be divided into high-risk and low-risk groups with significant differences (P = 2.052e - 05), and the discrepancy of immune profiles between these two risk groups was illustrated by principal components analysis. Taken together, the novel survival predictive model created by the four immune-related lncRNAs showed promising clinical prediction value in cervical cancer.

Long non-coding RNA SOX21-AS1 modulates lung cancer progress upon microRNA miR-24-3p/PIM2 axis

Lung cancer is a lethal cancer that threatens human health. Several studies have demonstrated the role of long non-coding RNAs (lncRNAs) in lung cancer. SOX21-AS1 is a newly discovered oncogenic lncRNA, but its molecular mechanism in lung cancer is not known. Here, the levels of SOX21-AS1, miR-24-3p, and PIM2 were examined in lung cancer and normal tissues. The relationships between miR-24-3p and SOX21-AS1 or PIM2 were predicted using bioinformatics tools and confirmed using a luciferase reporter assays. Colony formation, MTT, flow cytometry, and transwell assays were conducted to analyze cell proliferation, apoptosis, migration, and invasion abilities, respectively. Western blotting was used to measure PIM2 expression levels in cancer tissues and cells. SOX21-AS1 expression levels were high in lung cancer tissues and cells. In contrast, the amount of miR-24-3p bound to SOX21-AS1 was relatively low in cancerous tissues and cells. The knockdown of SOX21-AS1 decreased cell proliferation, activated apoptosis, and promoted cell migration and invasion. These effects were abolished by miR-24-3p inhibition. The oncogenic function of SOX21-AS1 mediated through targeting miR-24-3p was also demonstrated in animal models. PIM2 was targeted by miR-24-3p and showed increased levels in tumor tissues and cells. Furthermore, miR-24-3p overexpression inhibited the proliferation and promoted the apoptosis of lung cancer cells. In lung cancer cells, SOX21-AS1 negatively modulated the miR-24-3p/PIM2 axis to facilitate their proliferation, migration, and invasion. These findings offer a novel idea for future research on treating lung cancer at the molecular level.

The Biological Significance of Long noncoding RNAs Dysregulation and their Mechanism of Regulating Signaling Pathways in Cervical Cancer

Despite the remarkable decrease in cervical cancer incidence due to the availability of the HPV vaccine and implementation of screening programs for early detection in developed countries, this cancer remains a major health problem globally, especially in developing countries where most of the cases and mortality occur. Therefore, more understanding of molecular mechanisms of cervical cancer development might lead to the discovery of more effective diagnosis and treatment options. Research on long noncoding RNAs (lncRNAs) demonstrates the important roles of these molecules in many physiological processes and diseases, especially cancer. In the present review, we discussed the significance of lncRNAs altered expression in cervical cancer, highlighting their roles in regulating highly conserved signaling pathways, such as mitogen-activated protein kinase (MAPK), Wnt/β-catenin, Notch, and phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathways and their association with the progression of cervical cancer in order to bring more insight and understanding of this disease and their potential implications in cancer diagnosis and therapy.

The promotion of cervical cancer progression by signal transducer and activator of transcription 1-induced up-regulation of lncRNA MEOX2-AS1 as a competing endogenous RNA through miR-143-3p/VDAC1 pathway

Long non-coding RNAs (lncRNAs) are the new regulators and biomarkers for various tumors. However, in cervical cancer (CC), the potential roles of lncRNAs are not well characterized. This research aimed at exploring the roles of MEOX2 antisense RNA 1(MEOX2-AS1) in CC progression and the underlying mechanisms. The examination of MEOX2-AS1 levels in CC specimens and cell lines was conducted by RT-PCR. Loss-of-function experiments were performed for the assays of proliferation, migration, and invasion of CC cells after various treatments. Animal experiments were applied for the determination of the effects of MEOX2-AS1 in vivo. Bioinformatics analysis, together with dual-luciferase reporter assays, was applied to demonstrate the possible relationships among MEOX2-AS1, miR-143-3p and VDAC1. In the paper, we reported that MEOX2-AS1 levels were distinctly upregulated in CC cells and tissues, and higher MEOX2-AS1 expressions indicated a poor clinical outcome. Besides, STAT1 could activate transcriptions of MEOX2-AS1 by binding directly to its promoter region. The silence of MEOX2-AS1 suppressed the metastatic and proliferative ability of CC cells, as revealed by functional assays. Mechanistically, MEOX2-AS1 sponged miR-143-3p to regulate VDAC1 expressions. Furthermore, miR-143-3p inhibitor reversed the anti-proliferation and anti-metastasis effect of MEOX2-AS1 knockdown. Overall, the data indicated that the MEOX2-AS1/miR-143-3p/VDAC1 pathway participated in CC progression, making it a novel therapeutic target for CC cures.

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

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

Integrative analysis of the gastric cancer long non-coding RNA-associated competing endogenous RNA network

Gastric cancer (GC) is a common type of cancer, and identification of novel diagnostic biomarkers associated with this disease is important. The present study aimed to identify novel diagnostic biomarkers associated with the prognosis of GC, using an integrated bioinformatics approach. Differentially expressed long non-coding RNAs (lncRNAs) associated with GC were identified using Gene Expression Omnibus datasets (GSE58828, GSE72305 and GSE99416) and The Cancer Genome Atlas database. A competing endogenous RNA network that incorporated five lncRNAs [long intergenic non-protein coding RNA 501 (LINC00501), LINC00365, SOX21 antisense divergent transcript 1 (SOX21-AS1), GK intronic transcript 1 (GK-IT1) and DLEU7 antisense RNA 1 (DLEU7-AS1)], 29 microRNAs and 114 mRNAs was constructed. Gene Ontology and protein-protein interaction network analyses revealed that these lncRNAs may be involved in 'biological regulation', 'metabolic process', 'cell communication', 'developmental process', 'cell proliferation', 'reproduction' and the 'cell cycle'. The results of receiver operating characteristic curve analysis demonstrated that LINC00501 (AUC=0.819), LINC00365 (AUC=0.580), SOX21-AS1 (AUC=0.736), GK-IT1 (AUC=0.823) and DLEU7-AS1 (AUC=0.932) had the potential to become valuable diagnostic biomarkers for GC. Associations with clinicopathological characteristics demonstrated that LINC00501 expression was significantly associated with sex (P=0.015) and tumor grade (P=0.022). Furthermore, LINC00365 expression was significantly associated with lymph node metastasis (P=0.025). Gene set enrichment analysis revealed that LINC00501, LINC00365 and SOX21-AS1 were enriched in signaling pathways associated with GC. Reverse transcription-quantitative PCR analysis demonstrated that LINC00501 expression (P=0.043) was significantly upregulated in GC tissues, whereas the expression levels of LINC00365 (P=0.033) and SOX21-AS1 (P=0.037) were significantly downregulated in GC tissues. Taken together, the results of the present study suggest that LINC00501, LINC00365, SOX21-AS1, GK-IT1 and DLEU7-AS1 may be used as novel diagnostic biomarkers for GC, and may be functionally associated with GC development and progression.

Long noncoding RNA GAS8-AS1: A novel biomarker in human diseases

Long non-coding RNAs (lncRNAs) represent a group of ncRNAs with more than 200 nucleotides. These RNAs can specifically regulate gene expression at both the transcriptional and the post-transcriptional levels, and increasing evidence indicates that they play vital roles in a variety of disease-related cellular processes. The lncRNA GAS8 antisense RNA 1 (GAS8-AS1, also known as C16orf3) is located in the second intron of GAS8 and has been reported to be both abnormally expressed in several diseases and closely correlated with many clinical characteristics. GAS8-AS1 has been shown to affect many biological functions, including cell proliferation, migration, invasiveness, and autophagy using several signaling pathways. In this review, we have summarized current studies on GAS8-AS1 roles in disease and discuss its potential clinical utility. GAS8-AS1 may be a promising biomarker for both diagnoses and prognoses, and a novel target for many disease therapies.

Long non-coding RNA RP11-284F21.9 functions as a ceRNA regulating PPWD1 by competitively binding to miR-769-3p in cervical carcinoma

Cervical carcinoma is the most common gynecological cancer in women worldwide. Emerging evidence has shown that long non-coding RNAs (lncRNAs) participate in multiple biological processes of cervical carcinoma tumorigenesis. We aimed to investigate the function of a novel lncRNA RP11-284F21.9 in cervical carcinoma. We found that RP11-284F21.9 was down-regulated in cervical carcinoma tissues and cell lines. Overexpression of RP11-284F21.9 inhibits proliferation, invasion and migration of cervical carcinoma cells in vitro. Further, we identified that RP11-284F21.9 directly interacted with miR-769-3p and functioned as the miR-769-3p sponge. Mechanistically, we showed that miR-769-3p regulated peptidylprolyl isomerase domain and WD repeat-containing protein1 (PPWD1) expression by targeting PPWD1 3′-UTR. Furthermore, xenograft tumor model revealed that overexpression of RP11-284F21.9 inhibited tumor growth of cervical carcinoma in vivo. Taken together, our results demonstrate that RP11-284F21.9 functions as tumor suppressor and regulates PPWD1 expression through competitively binding to miR-769-3p in cervical carcinoma, suggesting that RP11-284F21.9/miR-769-3p/PPWD1 axis could serve as a promising prognostic biomarker and therapeutic target for cervical carcinoma.

MiR-7 in Cancer Development

MicroRNAs (miRNAs) are short non-coding RNA involved in the regulation of specific mRNA translation. They participate in cellular signaling circuits and can act as oncogenes in tumor development, so-called oncomirs, as well as tumor suppressors. miR-7 is an ancient miRNA involved in the fine-tuning of several signaling pathways, acting mainly as tumor suppressor. Through downregulation of PI3K and MAPK pathways, its dominant role is the suppression of proliferation and survival, stimulation of apoptosis and inhibition of migration. Besides these functions, it has numerous additional roles in the differentiation process of different cell types, protection from stress and chromatin remodulation. One of the most investigated tissues is the brain, where its downregulation is linked with glioblastoma cell proliferation. Its deregulation is found also in other tumor types, such as in liver, lung and pancreas. In some types of lung and oral carcinoma, it can act as oncomir. miR-7 roles in cell fate determination and maintenance of cell homeostasis are still to be discovered, as well as the possibilities of its use as a specific biotherapeutic.

The Role of miRNA-7 in the Biology of Cancer and Modulation of Drug Resistance

MicroRNAs (miRNAs, miRs) are small non-coding RNA (ncRNA) molecules capable of regulating post-transcriptional gene expression. Imbalances in the miRNA network have been associated with the development of many pathological conditions and diseases, including cancer. Recently, miRNAs have also been linked to the phenomenon of multidrug resistance (MDR). MiR-7 is one of the extensively studied miRNAs and its role in cancer progression and MDR modulation has been highlighted. MiR-7 is engaged in multiple cellular pathways and acts as a tumor suppressor in the majority of human neoplasia. Its depletion limits the effectiveness of anti-cancer therapies, while its restoration sensitizes cells to the administered drugs. Therefore, miR-7 might be considered as a potential adjuvant agent, which can increase the efficiency of standard chemotherapeutics.

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

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

Long non-coding RNA SOX21-AS1 enhances the stemness of breast cancer cells via the Hippo pathway

Breast cancer stem cells (BCSCs) have high tumorigenicity and invasiveness, which contributes to recurrence and metastasis. The long non‐coding RNA SOX21‐AS1 has been previously reported to modulate the properties of breast cancer stem cells via targeting SOX2, although the underlying molecular mechanisms remain unclear. To investigate this issue, we first confirmed that the expression level of SOX21‐AS1 is increased in breast cancer tissues and cell lines (MCF‐7, MDA‐MB‐231, CSC‐MCF‐7, CSC‐MDA‐MB‐231), especially in BCSCs. We demonstrated that SOX21‐AS1 promotes the stemness of CSC‐MCF‐7 cells through western blot detection of stemness‐related proteins, as well as side population and sphere formation assays. Overexpression of SOX21‐AS1 enhanced the proliferation, migration and invasion of CSC‐MCF‐7 cells. We also observed that SOX21‐AS1 inhibited the Hippo pathway. SOX21‐AS1 enhanced the stemness, migration and invasion of CSC‐MCF‐7 cells by increasing the nuclear localization of YAP and decreasing the level of pYAP. Overall, we conclude that SOX21‐AS1 may promote the stemness viability, proliferation, migration and invasion of BCSCs by inhibiting the Hippo pathway. Our findings provide insights into potential biomarkers and prognostic measures for the treatment of breast cancer.

Long non-coding RNA DSCAM-AS1 contributes to the tumorigenesis of cervical cancer by targeting miR-877-5p/ATXN7L3 axis

Cervical cancer (CC) is ranked as the fourth most common cancer that occurs in women universally, which normally causes pain in the lower belly. Plenty of studies have stated that the expression of long non-coding RNAs (lncRNAs) is linked to the cellular development of many kinds of cancers. DSCAM-AS1 has been reported to act as an oncogene in other cancer types and the aim of our study was to uncover the function and regulatory mechanism of DSCAM-AS1 in CC. In this research, our findings presented that DSCAM-AS1 expression was up-regulated in CC cells. DSCAM-AS1 led to the development of CC by enhancing cell proliferation, migration and invasion ability. DSCAM-AS1 was verified to combine with miR-877-5p and down-regulate the expression of miR-877-5p. Results also showed that ATXN7L3 was a downstream target gene of miR-877-5p and it was unfavorably modulated by miR-877-5p. Enhanced expression of ATXN7L3 counterbalanced the DSCAM-AS1 knockdown effect on the progression of CC. This was the first time to analyze the underlying regulatory mechanism of the oncogenic DSCAM-AS1. Our findings clarified that DSCAM-AS1 played as an oncogenic lncRNA by targeting miR-877-5p/ATXN7L3 axis to promote CC progression, which may provide insights into the prevention of CC.

Long-Chain Non-Coding SOX21-AS1 Promotes Proliferation and Migration of Breast Cancer Cells Through the PI3K/AKT Signaling Pathway

Aim

This study aimed to investigate the effect of long-chain non-coding SOX21-AS1 on the proliferation and migration of breast cancer (BC) cells through the PI3K/AKT signaling pathway.

Methods

Eighty-eight BC and adjacent tissues were collected, and BC cells and normal breast epithelial cells were purchased. LncRNA SOX21-AS1 expression in tissues and cells was detected by RT-PCR. miR-NC, si-SOX21-AS1, and Sh-SOX21-AS1 were transfected into BC cells. The PI3K/AKT signaling pathway was interfered with L740Y-P (activator of the PI3K/AKT pathway) and LY294002 (inhibitor of the PI3K/AKT pathway) in BC cells. The SOX21-AS1 expression in BC tissues and cells was tested by qRT-PCR, and the expression levels of p-PI3K, p-AKT, N-cadherin, E-cadherin, and vimentin were detected by WB.

Results

SOX21-AS1 was highly expressed in BC, and the p-PI3K and p-AKT levels were also high. Cell experiments showed that inhibiting SOX21-AS1 expression could inhibit the proliferation, invasion, migration, and EMT of BC cells, and up-regulating its expression could promote the proliferation, invasion, migration, and EMT of ovarian cancer cells. The tumor-forming experiment in nude mice was consistent with the results in vitro. 740Y-P intervention could reverse the inhibition effect of Si-SOX21-AS1 on BC cell proliferation, invasion, migration, and EMT, while LY294002 intervention could reverse the promotion effect of Sh-SOX21-AS1 on BC cell proliferation, invasion, migration, and EMT.

Conclusion

SOX21-AS1 is highly expressed in BC tissues. Silencing BC expression can inhibit the proliferation, invasion, migration, and EMT of cells by inhibiting the PI3K/AKT signaling pathway, which may be a new target for diagnosis and treatment.

Aberrant Methylation of the SOX21-AS1 Promoter Region Promotes Gene Expression and Its Clinical Value in Cervical Cancer

Cervical cancer is the fourth most common female cancer worldwide. Long non-coding RNAs (lncRNAs), such as SOX21-AS1, play pivotal roles in the progression and metastasis of cancer. We previously described that SOX21-AS1 was hypomethylated in cervical cancer (CC) and aimed to further explore the relationship between methylation of the SOX21-AS1 promoter and CC using clinical cervical samples. Pyrosequencing was performed to detect the methylation status of the SOX21-AS1 promoter in 33 cervical specimens. Additionally, expression levels of related genes in 43 clinical cervical specimens were measured using quantitative real-time PCR (qRT-PCR). The SOX21-AS1 promoter was significantly hypomethylated in CC (P < 0.01). SOX21-AS1 hypomethylation was also significantly associated with an advanced Federation of Gynecology and Obstetrics (FIGO) stage (P < 0.01). The expression levels of SOX21-AS1 and SOX21 were noted to be higher in cancer vs. normal cervix (all P < 0.001). Moreover, the expression of SOX21-AS1 was positively correlated with SOX21 in all samples (r = 0.891, P < 0.001). Methylation statue of the SOX21-AS1 promoter region was negatively correlated with the expression levels of SOX21-AS1 and SOX21 (SOX21-AS1, r = - 0.628; SOX21, r = - 0.648; both P < 0.001). The methylation status of SOX21-AS1 displayed promising diagnostic potential for CC, exhibiting good sensitivity (100.0%) and specificity (69.2%), with an area under the curve of 0.846. In addition, bioinformatic analyses identified a potential link between SOX21-AS1 and the Wnt signaling pathway. Furthermore, methylation status of SOX21-AS1 was negatively correlated with β-catenin/c-myc/cyclin D1 mRNA levels (r_s = - 0.529, - 0.462 ,and - 0.383, respectively, P < 0.05). Our findings illuminated that lncRNA SOX21-AS1 showed hypomethylation in cervical cancer and SOX21-AS1 could serve as a novel biomarker for CC diagnosis or a potential therapeutic target.

Role of microRNA-7 in liver diseases: a comprehensive review of the mechanisms and therapeutic applications

MicroRNA-7 (miR-7) is a small non-coding RNA, which plays critical roles in regulating gene expression of multiple key cellular processes. MiR-7 exhibits a tissue-specific pattern of expression, with abundant levels found in the brain, spleen, and pancreas. Although it is expressed at lower levels in other tissues, including the liver, miR-7 is involved in both the development of organs and biological functions of cells. In this review, we focus on the mechanisms by which miR-7 controls cell growth, proliferation, invasion, metastasis, metabolism, and inflammation. We also summarize the specific roles of miR-7 in liver diseases. MiR-7 is considered as a tumor suppressor miRNA in hepatocellular carcinoma and is involved in the pathogenesis of hepatic steatosis and hepatitis. Future studies to further define miR-7 functions and its mechanism in association with other types of liver diseases should be explored. An improved understanding from these studies will provide us a useful perspective leading to mechanism-based intervention by targeting miR-7 for the treatment of liver diseases.

Silencing of long non-coding RNA SOX21-AS1 inhibits lung adenocarcinoma invasion and migration by impairing TSPAN8 via transcription factor GATA6

Here, we revealed the novel role of long non-coding RNAs (lncRNAs) SOX21 antisense RNA 1 (SOX21-AS1)/TSPAN8/GATA6 in progression of lung adenocarcinoma. SOX21-AS1 expression was quantified in lung adenocarcinoma tissues and cells by RT-qPCR. Then, gain- and loss-of-function experiments were conducted in lung adenocarcinoma cells. Expression of GATA6, TSPAN8 and extracellular signal-regulated kinase (ERK) signaling pathway-related genes was determined in lung adenocarcinoma cells by western blot analysis. The interaction and relationship among SOX21-AS1, GATA6 and TSPAN8 were predicted and verified respectively by RNA pull down, RIP, ChIP, and dual-luciferase reporter assays. Next, lung adenocarcinoma cell proliferation, colony formation, invasion and migration were assessed by 5-ethynyl-2'-deoxyuridine staining, colony formation assay and Transwell assay. Xenograft tumors were established in nude mice and the tumor growth was observed and recorded. SOX21-AS1 was observed to be highly expressed in lung adenocarcinoma tissues. The overexpression of SOX21-AS1, GATA6 or TSPAN8 obviously enhanced cell biological functions in lung adenocarcinoma. Meanwhile, SOX21-AS1 interacted with GATA6 which bound to TSPAN8 promoter and promoted TSPAN8 expression, which further enhanced cell colony formation, proliferation and invasion, and also activated ERK signaling pathway. Silencing of SOX21-AS1 and inhibiting its binding to GATA6 downregulate TSPAN8 and thereby exert anti-oncogenic effects in lung adenocarcinoma.

Long non-coding RNA in cervical cancer: From biology to therapeutic opportunity

Genome regions that do not for code for proteins are generally transcribed into long non-coding RNAs. Growing evidence reveals that lncRNAs, defined as transcripts longer than 200 nucleotides, are commonly deregulated in cervical malignancies. New sequencing technologies have revealed a complete picture of the composition of the human transcriptome. LncRNAs perform diverse functions at transcriptional, translation, and post-translational levels through interactions with proteins, RNA and DNA. In the past decade, studies have shown that lncRNAs participate in the pathogenesis of many diseases, including cervical cancer. Hence, illuminating the roles of lncRNA will improve our understanding of cervical cancer. In this work, we summarize the current knowledge on lncRNAs in cervical cancer. We describe the emerging roles of lncRNAs in cervical cancer, particularly in cancer progression, metastasis, treatment resistance, HPV regulation, and metabolic reprogramming. The great promises of lncRNAs as potential biomarkers for cervical cancer diagnosis and prognosis are also discussed. We discuss current technologies used to target lncRNAs and thus control cancers, such as antisense oligonucleotides, CRISPR-Cas9, and exosomes. Overall, we show that lncRNAs hold great potentials as therapeutic agents and innovative biomarkers. Finally, further clinical research is necessary to advance our understanding of the therapeutic value of lncRNAs in cervical cancer.

LncRNA HAND2-AS1 represses cervical cancer progression by interaction with transcription factor E2F4 at the promoter of C16orf74

Cervical cancer is one of the major malignancies, the pathophysiology and progression of which remain to be scarcely understood. Long non-coding RNAs (lncRNAs) have been previously implicated in the progression of cervical cancer. Here, the purpose of this study was to identify whether lncRNA heart- and neural crest derivative-expressed 2-antisense RNA 1 (HAND2-AS1) affect the development of cervical cancer through regulation of chromosome 16 open reading frame 74 (C16orf74) by mediating a transcription factor E2F4. RT-qPCR was performed to determine the expression of HAND2-AS1 in cervical cancer cells. Then, cervical cancer cells were treated with HAND2-AS1 or si-E2F4 RNA, or C16orf74, after which the proliferation, colony formation, migration and invasion were detected. Moreover, the binding between HAND2-AS1 and E2F4 or between E2F4 and C16orf74 was explored. Finally, the tumorigenesis of cervical cancer cells was measured in nude mice with altered HAND2-AS1/E2F4/C16orf74 expression. HAND2-AS1 exhibited poor expression in cervical cancer, and HAND2-AS1 overexpression suppressed the proliferation, colony formation, migration and invasion of cervical cancer cells. In addition, HAND2-AS1 was found to recruit transcription factor E2F4 to C16orf74 promoter region and down-regulate C16orf74 expression. Lastly, HAND2-AS1/E2F4/C16orf74 modulated the tumorigenesis of cervical cancer in nude mice. In conclusion, this study provided evidence on the inhibitory effect of HAND2-AS1 on the development of cervical cancer through the suppression of C16orf74 expression by recruiting transcription factor E2F4. This study highlights the potential of lncRNA HAND2-AS1 as a target in the treatment of cervical cancer.

Long noncoding RNA SOX21-AS1 regulates the progression of triple-negative breast cancer through regulation of miR-520a-5p/ORMDL3 axis

Recently, long noncoding RNAs (lncRNAs) have been reported as a new kind of controllers about cancer processes in biology. In spite of the dysregulation of lncRNAs in various kinds of cancers, only a little of the information was effective on the expression configuration and inner effects of lncRNAs in triple-negative breast cancer (TNBC). This study valued the expression of lncRNA SOX21-AS1 and the biological role it played in TNBC. In our research, SOX21-AS1 had a high expression in TNBC cell lines. The functional experiments showed that knockdown of SOX21-AS1 obviously restrained cell proliferation, migration, invasion, and epithelial-mesenchymal transition process and promoted cell apoptosis. Mechanistically, SOX21-AS1 was found to bind with miR-520a-5p. Besides, ORMDL3 was identified as a downstream target of miR-520a-5p, and the suppressed ORMDL3 expression induced by silenced SOX21-AS1 could be restored by miR-520a-5p inhibition. Further, data from rescue assays revealed that SOX21-AS1 could regulate the malignancy of TNBC via miR-520a-5p/ORMDL3 axis. All in all, we identified that SOX21-AS1 regulated the cellular process of TNBC cells via antagonizing miR-520a-5p availability to upregulate ORMDL3 expression.

Long Non-Coding RNA TMPO-AS1 Promotes Cervical Cancer Cell Proliferation, Migration, and Invasion by Regulating miR-143-3p/ZEB1 Axis

Objective

Long non-coding RNAs (lncRNAs) have been identified as important players in tumorigenesis. LncRNA TMPO antisense RNA 1 (TMPO-AS1) has been shown to be involved in several tumors. However, the functional role and the underlying mechanism of TMPO-AS1 in regulating cervical cancer cell behavior remain unclear.

Materials and Methods

Expression of TMPO-AS1, miR-143-3p, and ZEB1 were examined by qRT-PCR and Western blot. Cell proliferation, migration and invasion were evaluated using CCK-8 assay and Transwell migration and invasion assays, respectively. Luciferase reporter assay was performed to investigate the interaction miR-143-3p and TMPO-AS1 or ZEB1.

Results

TMPO-AS1 was highly expressed in cervical cancer cells. Furthermore, TMPO-AS1 overexpression significantly promoted C-33A cell proliferation, migration, and invasion. In contrast, TMPO-AS1 silencing inhibited SiHa cell proliferation, migration, and invasion. Mechanistically, TMPO-AS1 acted as a sponge of miR-143-3p to elevate expression of zinc finger E-box binding homeobox 1 (ZEB1), a target of miR-143-3p, and thereby promoted C-33A cell proliferation, migration, and invasion. Further assays showed that TMPO-AS1 knockdown inhibited cervical cancer cell tumorigenesis in vivo.

Conclusion

TMPO-AS1 promotes cervical cancer cell proliferation, migration, and invasion by regulating the miR-143-3p/ZEB1 axis.

Long Noncoding RNA FOXD2-AS1 Promotes the Malignancy of Cervical Cancer by Sponging MicroRNA-760 and Upregulating Hepatoma-Derived Growth Factor

Although the functions of long noncoding RNA (lncRNA) called FOXD2 adjacent opposite strand RNA 1 (FOXD2-AS1) have been well studied in multiple human cancer types, its expression status and detailed roles in cervical cancer remain unknown and merit investigation. This study was aimed at assessing FOXD2-AS1 expression in cervical cancer and at determining its effects on the aggressive behavior of cervical cancer in vitro and in vivo. Expression of FOXD2-AS1 in cervical cancer tissues and cell lines was determined via reverse-transcription quantitative PCR. The effects of FOXD2-AS1 on cervical cancer cells were examined by a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, flow-cytometric analysis, migration and invasion assays, and an in vivo tumorigenicity assay. FOXD2-AS1 was found to be significantly upregulated in cervical cancer tissues and cell lines. High FOXD2-AS1 expression was notably linked with the Federation of Gynecology and Obstetrics (FIGO) stage, lymph node metastasis, and depth of cervical invasion in patients with cervical cancer. Kaplan-Meier survival analysis revealed significantly shorter overall survival of patients when the tumor expression of FOXD2-AS1 was higher in comparison with those in patients with lower FOXD2-AS1 expression. In vitro functional assays revealed that downregulation of FOXD2-AS1 led to suppression of proliferation, migration, and invasiveness as well as to the induction of apoptosis of cervical cancer cells. In addition, FOXD2-AS1 silencing hindered tumor growth in vivo. Mechanism investigation revealed that FOXD2-AS1 functioned as a molecular sponge of microRNA-760 (miR-760). Furthermore, hepatoma-derived growth factor (HDGF) was validated as a direct target gene of miR-760 in cervical cancer cells. Moreover, an miR-760 knockdown reversed the effects of FOXD2-AS1 silencing on cervical cancer cells. FOXD2-AS1 possesses significant oncogenic activity in cervical cancer progression; this activity is mediated by sponging of miR-760 with consequent upregulation of HDGF. The FOXD2-AS1-miR-760-HDGF axis might harbor promising targets for novel treatment strategies of cervical cancer.

Circular RNA circABCC4 regulates lung adenocarcinoma progression via miR-3186-3p/TNRC6B axis

Lung adenocarcinoma (LUAD), a general kind of bronchogenic malignancy globally, is depicted as one of the most critical factors affecting human health severely. Featured with loop structure, circular RNA (circRNA) has been described as an essential regulator of multiple human malignancies. Nevertheless, knowledge concerning the regulatory function of circRNA in LUAD progression remains limited. Identified as a novel circRNA, circABCC4 has not been studied in LUAD as yet. This is the first time to probe into the underlying role of circABCC4 in LUAD. In this study, a notably elevated expression of circABCC4 was found in LUAD tissues and cells. Besides, circABCC4 is verified to be characterized with a circular structure in LUAD. Functional assays elucidated that knockdown of circABCC4 significantly impaired LUAD cell proliferation, migration as well as accelerated cell apoptosis. Molecular mechanism experiments later revealed that circABCC4 could bind with miR-3186-3p and miR-3186-3p was a tumor suppressor in LUAD. Moreover, TNRC6B was validated to combine with miR-3186-3p, and its expression was respectively negatively and positively regulated by miR-3186-3p and circABCC4 in LUAD. Final rescue experiments further delineated that TNRC6B upregulation partially restored circABCC4 downregulation-mediated effect on LUAD progression. In sum, circABCC4 regulates LUAD progression via miR-3186-3p/TNRC6B axis.

Proneural and mesenchymal glioma stem cells display major differences in splicing and lncRNA profiles

Therapy resistance and recurrence in high-grade gliomas are driven by their populations of glioma stem cells (GSCs). Thus, detailed molecular characterization of GSCs is needed to develop more effective therapies. We conducted a study to identify differences in the splicing profile and expression of long non-coding RNAs in proneural and mesenchymal GSC cell lines. Genes related to cell cycle, DNA repair, cilium assembly, and splicing showed the most differences between GSC subgroups. We also identified genes distinctly associated with survival among patients of mesenchymal or proneural subgroups. We determined that multiple long non-coding RNAs with increased expression in mesenchymal GSCs are associated with poor survival of glioblastoma patients. In summary, our study established critical differences between proneural and mesenchymal GSCs in splicing profiles and expression of long non-coding RNA. These splicing isoforms and lncRNA signatures may contribute to the uniqueness of GSC subgroups, thus contributing to cancer phenotypes and explaining differences in therapeutic responses.

LncRNA CAR10 Upregulates PDPK1 to Promote Cervical Cancer Development by Sponging miR-125b-5p

Cervical cancer is one of the malignant tumors that seriously threaten women's health. The mechanism of development needs to be deeply studied. In recent years, lncRNA has been identified as one of the important factors affecting the malignant progression of tumors. In this study, we illustrated the important mechanism of lncRNA CAR10 in the development of cervical cancer. We found that CAR10 is significantly increased in4 cervical cancer tissues and cells, which can promote the proliferation of cervical cancer cells in vitro and in vivo, indicating that CAR10 is involved in the progression of cervical cancer as an oncogene. Further studies showed that CAR10 is a target gene of miR-125b-5p, and miR-125b-5p can inhibit the effect of CAR10 on the proliferation of cervical cancer cells. In addition, we also found that 3-phosphoinositide-dependent protein kinase 1 (PDPK1) is also a target gene of miR-125b-5p, and CAR10 can upregulate the expression level of PDPK1. The results showed that CAR10 acts as a ceRNA to upregulate the expression of PDPK1 by sponging miR-125b-5p. Knockdown of PDPK1 can inhibit the effect of CAR10 on cervical cancer cells. Our study demonstrates that, based on ceRNA mechanism, CAR10/miR-125b-5p/PDPK1 network can regulate the proliferation of cervical cancer cells and play an important role in the development of cervical cancer. In addition, our study also suggests that intervention of CAR10/miR-125b-5p/PDPK1 network may be a new strategy for targeted therapy of cervical cancer.