Telomere-to-mitochondria signalling by ZBP1 mediates replicative crisis.

Cancers arise through the accumulation of genetic and epigenetic alterations that enable cells to evade telomere-based proliferative barriers and achieve immortality. One such barrier is replicative crisis-an autophagy-dependent program that eliminates checkpoint-deficient cells with unstable telomeres and other cancer-relevant chromosomal aberrations1,2. However, little is known about the molecular events that regulate the onset of this important tumour-suppressive barrier. Here we identified the innate immune sensor Z-DNA binding protein 1 (ZBP1) as a regulator of the crisis program. A crisis-associated isoform of ZBP1 is induced by the cGAS-STING DNA-sensing pathway, but reaches full activation only when associated with telomeric-repeat-containing RNA (TERRA) transcripts that are synthesized from dysfunctional telomeres. TERRA-bound ZBP1 oligomerizes into filaments on the outer mitochondrial membrane of a subset of mitochondria, where it activates the innate immune adapter protein mitochondrial antiviral-signalling protein (MAVS). We propose that these oligomerization properties of ZBP1 serve as a signal amplification mechanism, where few TERRA-ZBP1 interactions are sufficient to launch a detrimental MAVS-dependent interferon response. Our study reveals a mechanism for telomere-mediated tumour suppression, whereby dysfunctional telomeres activate innate immune responses through mitochondrial TERRA-ZBP1 complexes to eliminate cells destined for neoplastic transformation.

Overexpression of lncRNA HOXA-AS2 promotes the progression of oral squamous cell carcinoma by mediating SNX5 expression.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most common head and neck cancers. Long non-coding RNA HOXA-AS2 (lncRNA HOXA-AS2) have been extensively studied in various cancers. However, the expression and function of HOXA-AS2 in OSCC still remain unknown. The aim of this study is to investigate the roles of HOXA-AS2 in OSCC. METHODS: OSCC tissues and adjacent normal tissues were obtained from OSCC patients. RT-qPCR and Western blot assays were used to detect the expression of target genes in OSCC tissues or cells. Cells proliferation, migration and invasion were detected by CCK-8 and transwell assays, respectively. The target gene of HOXA-AS2 was confirmed by dual-luciferase reporter gene assay. RESULTS: We found that HOXA-AS2 expression was remarkably upregulated in OSCC tissues and cell lines. The downregulation of HOXA-AS2 inhibited cells proliferation, migration and invasion. Our bioinformatics analysis found that HOXA-AS2 can target miR-520c-3p, which was confirmed by dual-luciferase reporter gene assay. The expression of HOXA-AS2 was found to be negatively associated with miR-520c-3p in OSCC tissues. Moreover, sorting nexin 5 (SNX5), a downstream target of miR-520c-3p, was inhibited by miR-520c-3p overexpression. SNX5 was also increased in OSCC tissues and cell lines. Additionally, we found that the higher expression of SNX5 was strongly associated with the tumor grade of OSCC patients in Oncomine database. Most importantly, the knockdown of HOXA-AS2 induced cells apoptosis by promoting autophagy by regulating SNX5. CONCLUSION: HOXA-AS2 served an oncogene and promoted OSCC progression via the miR-520c-3p/SNX5 axis. Thus, HOXA-AS2 may be a new biomarker for diagnosis and treatment of OSCC.

Serum-Based lncRNA ANRIL, TUG1, UCA1, and HIT Expressions in Breast Cancer Patients.

Breast cancer is a heterogeneous disease and is the most common and prevalent form of malignancy diagnosed in women. lncRNAs are found to be frequently dysregulated in cancer, and its expression plays a critical role in tumorigenesis. The study included 100 histopathologically confirmed, newly diagnosed untreated patients of invasive ductal carcinoma (IDC) of breast cancer patients and 100 healthy subjects. After blood collection, the serum was separated and total RNA was extracted, cDNA was synthesized using 100 ng of total RNA, and lncRNA (ANRIL, TUG1, UCA1, and HIT) expression was analyzed. Increased ANRIL (3.83-fold), TUG1 (7.64-fold), UCA1 (7.82-fold), and HIT (3.31-fold) expressions were observed in breast cancer patients compared to healthy controls. Relative expression of lncRNAs UCA-1 (p = 0.010) and HIT-1 (p < 0.0001) was significantly elevated in patients with advanced breast cancer stage compared to those with early-stage disease. While lncRNA TUG-1 expression was found to be higher in patients with early-stage tumors than those with advanced-stage tumors (p = 0.06), lncRNA ANRIL showed increased expression in patients with PR positive status (p = 0.04). However, we found a significant difference in lncRNA HIT expression in HER-2 positive breast cancer patients compared to HER-2 negative breast cancer patients (p = 0.005). An increase in the expression of serum lncRNAs ANRIL (p < 0.0001), UCA-1 (p = 0.004), and HIT (p < 0.0001) was observed in the distant organ metastatic breast cancer patients. In the ROC curve concerning lymph node involvement, the sensitivity and specificity of lncRNA HIT were 68% and 58%, respectively (p value = 0.007). In the ROC curve w.r.t. stages of disease, the sensitivity and specificity of lncRNA HIT were 80% and 50%, respectively (p value < 0.0001). Better sensitivity and specificity were observed for lncRNA HIT (sensitivity 91% and specificity 78%; p value < 0.0001) and ANRIL (sensitivity 70% and specificity 60%; p value < 0.0001) w.r.t distant organ metastases.

KHDRBS3 promotes paclitaxel resistance and induces glycolysis through modulated MIR17HG/CLDN6 signaling in epithelial ovarian cancer.

Paclitaxel (PTX) resistance contributes to mortality in epithelial ovarian cancer (EOC). Aerobic glycolysis is elevated in the tumor environment and may influence resistance to PTX in EOC. KH domain-containing, RNA-binding signal transduction-associated protein 3 (KHDRBS3) is an RNA binding protein that is up-regulated in EOC, but its underlying mechanism in EOC is unclear. Here, we investigate the role of KHDRBS3 in glycolysis and increased resistance to PTX. Expression of KHDRBS3 and Claudin (CLDN6) were measured in EOC tissue and cells by quantitative real-time PCR, western blotting and immunohistochemistry. The biological functions of KHDRBS3, MIR17HG and CLDN6 were examined using MTT, colony formation, apoptosis and seahorse assays in vitro. For in vivo experiments, a xenograft model was used to investigate the effects of KHDRBS3 and MIR17HG in EOC. Here, we investigate the role of KHDRBS3 in glycolysis and increased resistance to PTX. The expression of KHDRBS3 was up-regulated in PTX-resistant cells. KHDRBS3 knockdown restrained the IC50 of PTX, cell proliferation, colony formation and glycolysis in SKOV3-R and A2780-R cells in vitro and enhanced PTX sensitivity in a xenograft mouse model in vivo. KHDRBS3 interacts with lncRNA MIR17HG, which is down-regulated in EOC tissue and cells. The effect of KHDRBS3 overexpression on PTX resistance and glycolysis was rescued by MIR17HG overexpression. Additionally, MIR17HG interacts with the 3'UTR of CLDN6 and negatively regulates CLDN6 expression. MIR17HG overexpression suppressed the IC50 of PTX and glycolysis by targeting CLDN6. Our results reveal a KHDRBS3-MIR17HG-CLDN6 regulatory axis that contributes to enhanced glycolysis in EOC and represents a potential target for therapy.

Up-regulation of long noncoding RNA MBNL1-AS1 suppresses breast cancer progression by modulating miR-423-5p/CREBZF axis.

Breast cancer is the leading cause of cancer-related death among females, which is required to be solved urgently. Recent studies have found significant changes in a large number of genes and their transcriptional levels during breast cancer development, which are often closely related to the abnormal expression of long noncoding RNAs (lncRNAs). Herein, our study found that MBNL1-AS1 was down-regulated both in breast cancer tissues and cell lines, and it functioned as a tumor suppressor to inhibit cancer cell proliferation, migration, and invasion. MiR-423-5p was found to be a target of MBNL1-AS1 with an inverse relationship: an increase in miR-423-5p could counteract the inhibitory effect induced by MBNL1-AS1 on cancer cell promotion. Further, CREBZF was negatively regulated by miR-423-5p. Accordingly, CREBZF knockdown could impair the hindrance of cancer cell growth mediated by low miR-423-5p expression. Also, MBNL1-AS1 influenced the PI3K/AKT pathway, which was associated with cell proliferation and apoptosis, by regulating CREBZF. As a result, our work illustrated the tumor suppressor role of MBNL1-AS1 in breast cancer via upregulating miR-423-5p-targeted CREBZF. Thereby, the evidence indicates the complete understanding of the role of MBNL1-AS1/miR-423-5p/CREBZF axis in the regulation of breast cancer development, which could be used as a biomarker for predicating survival among breast cancer patients.

Abnormal expression of long non-coding RNA rhabdomyosarcoma 2-associated transcript (RMST) participates in the pathological mechanism of atherosclerosis by regulating miR-224-3p.

Study shows that long non-coding RNA (lncRNA) plays a regulatory role in cardiovascular diseases, and the mechanism of rhabdomyosarcoma 2-associated transcript (RMST) in atherosclerosis (AS) is still unclear. This study aimed to evaluate the expression of RMST and its possible role in the occurrence of AS. RMST and miR-224-3p level in serum and human umbilical vein endothelial cells (HUVECs) were determined by real-time quantitative PCR (RT-qPCR). In vitro atherosclerotic cell model was achieved by treating HUVECs with ox-LDL. Receiver operating characteristic (ROC) curve assessed the diagnostic value of RMST in AS, and Pearson correlation coefficient estimated the correlation of RMST with carotid intima-media thickness (CIMT) and carotid-femoral pulse wave velocity (cfPWV). Cell counting kit-8 (CCK-8) assay and Enzyme-linked immunosorbent assay (ELISA) were performed to evaluate the effect of RMST on cell viability and inflammatory response. The luciferase analysis was used to validate the relationship between RMST and miR-224-3p. The results showed that in serum and HUVECs, RMST levels were increased, while miR-224-3p level was decreased. ROC curve suggested that RMST had clinical diagnostic value for AS. Besides, CIMT and cfPWV were positively correlated with RMST levels, respectively. In HUVECs, RMST-knockdown notably improved the cell viability and inhibited the production of inflammatory factors. Moreover, miR-224-3p was the target of RMST. In conclusion, RMST has the potential to be a diagnostic marker for AS. RMST-knockdown contributes to the enhancement of cell viability and the inhibition of inflammatory response, which may provide new insights into the conquest of AS.

Long non-coding RNA prostate cancer-associated transcript 6 inhibited gefitinib sensitivity of non-small cell lung cancer by serving as a competing endogenous RNA of miR-326 to up-regulate interferon-alpha receptor 2.

The critical roles of lncRNAs in drug resistance of malignancies have been widely recognized. This investigation aims to study the function of lncRNA PCAT6 in the resistance of non-small cell lung cancer (NSCLC) to gefitinib. In our study, we demonstrated that prostate cancer-associated transcript 6 (PCAT6) was upregulated in gefitinib-resistant NSCLC. PCAT6 knockdown inhibited gefitinib resistance of NSCLC, as indicated by decreased IC50 value, proliferation, and metastasis, and increased cell apoptosis. Besides, PCAT6 could directly target miR-326 in gefitinib-resistant NSCLC cells and augment NSCLC resistance to gefitinib by serving as ceRNA of miR-326. Furthermore, interferon-alpha receptor 2 (IFNAR2) was validated as a downstream target of miR-326 and miR-326 reduced resistance to gefitinib by inhibiting IFNAR2 expression. Our investigation identified that PCAT6 enhanced gefitinib resistance of NSCLC via miR-326/IFNAR2 axis, which might offer a new therapeutic strategy against gefitinib resistance of NSCLC patients.

Transcriptome of visceral adipose tissue identifies an inflammation-related ceRNA network that regulates obesity.

Obesity is becoming an epidemic of widespread concern, but the underlying causes remain elusive. In this study, whole transcriptome RNA sequencing revealed differential profiles of noncoding (nc) RNAs and mRNAs in visceral adipose tissue from obese (BMI > 32.5 kg/m2) and lean (BMI < 20 kg/m2) individuals, with 1920 differentially expressed genes, 1466 long noncoding (lnc) RNAs, 122 micro (mi) RNAs, and 52 circular (circ) RNAs identified. Gene Set Enrichment Analysis, Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes analysis revealed that these ncRNAs were involved in inflammation-related pathways that included cytokine-cytokine receptor interaction, the tumor necrosis factor and nuclear factor kappa B signaling pathways. The results indicated a critical role of inflammation in the pathogenesis of obesity. The network interaction of lncRNA, circRNA, and miRNA revealed a competing endogenous (ce) RNA network that was associated with inflammation. The ceRNA network included circORC5/miR-197-5p/TNFRSF10D and circNTRK2/miR-760/LAT, which were dysregulated in obese patients. In conclusion, this whole transcriptome study provided a pool of data that will be useful for identifying biomarkers of obesity and identified an obesity-associated ceRNA network that is regulated by circORC5 and circNTRK2.

The anti-tumour effect of induced pluripotent stem cells against submandibular gland carcinoma in rats is achieved via modulation of the apoptotic response and the expression of Sirt-1, TGF-ß, and MALAT-1 in cancer cells.

The era of induced pluripotent stem cells (iPSCs) was used as novel biotechnology to replace embryonic stem cells bypassing the ethical concerns and problems of stem cell transplant rejection. The anti-tumour potential of iPSCs against many tumours including salivary cancer was proven in previous studies. The current study aimed to investigate the contribution of the Bax, Sirt-1, TGF-ß, and MALAT genes and/or their protein expression to the pathogenesis of submandibular carcinogenesis before and after iPSCs treatment. Thirty Wistar albino rats were equally assigned into three groups: group I (control), group II (Squamous cell carcinoma (SCC)): submandibular glands were injected SCC cells, and group III (SCC/iPSCs): SCC rats were treated by 5 × 106 iPSCs. Submandibular gland sections were subjected to histological and immunohistochemical analyses to detect mucopolysaccharides, Bax, and TGF-ß expression as well as PCR quantification for TGF-ß, Sirt-1, and lncRNA MALAT-1 gene expressions. Western blotting was also used to detect Sirt-1 and TGF-ß protein expressions. SCC group revealed infiltration by sheets of malignant squamous cells with or without keratin pearls and inflammatory cells, in addition to upregulation of TGF-ß, Sirt-1, MALAT-1, and Bax, whereas SCC/iPSCs group showed an improved submandibular histoarchitecture with the maintenance of the secretory function. Bax and TGF-ß immunoexpression were significantly reduced. The upregulated TGF-ß, Sirt-1, and MALAT-1 genes were significantly decreased. iPSCs protected against the experimentally induced submandibular gland carcinoma that might be achieved via their regenerative potential and their regulatory modulation of Sirt-1, TGF-ß, and MALAT-1 gene/protein expressions and of the apoptotic response in cancer cells.

Long-chain noncoding ribonucleic acids affect the survival and prognosis of patients with esophageal adenocarcinoma through the autophagy pathway: construction of a prognostic model.

Autophagy-related long-chain noncoding ribonucleic acids play a vital role in the development of esophageal adenocarcinoma. This study aimed to construct a prognostic model of autophagy-related long-chain noncoding ribonucleic acids and identify potential therapeutical targets for esophageal adenocarcinoma. We downloaded 261 long-chain noncoding RNA transcript samples and clinical data of 87 esophageal adenocarcinoma patients from the Cancer Genome Atlas and 307 autophagy-related genes from www.autophagy.com. We performed Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analyses and Gene Set Enrichment Analysis to determine risk characteristics and bioinformatics functions of signal transduction pathways. Univariate and multivariate Cox regression analyses were used to determine the correlation between autophagy-related long-chain noncoding ribonucleic acids and independent risk factors. The receiver operating characteristic analysis was used to evaluate the feasibility of the prognostic model. Finally, we performed survival analysis, risk analysis and independent prognostic analysis to verify the prognostic model of esophageal adenocarcinoma. We identified 22 autophagic long-chain noncoding ribonucleic acids that were highly correlated with the overall survival of esophageal adenocarcinoma patients. The areas under the receiver operating characteristic curve (0.941) and the calibration curve were significantly similar. Moreover, univariate and multivariate Cox regression analyses indicated that autophagy-related long-chain noncoding ribonucleic acids were independent predictors of esophageal adenocarcinoma. We found that autophagy-related long-chain noncoding ribonucleic acids might affect tumor development and prognosis in esophageal adenocarcinoma patients. The findings indicate that the prognostic model of esophageal adenocarcinoma has potential therapeutic applications in patients with esophageal adenocarcinoma.

Compressive force-induced LincRNA-p21 inhibits mineralization of cementoblasts by impeding autophagy.

The mineralization capability of cementoblasts is the foundation for repairing orthodontic treatment-induced root resorption. It is essential to investigate the regulatory mechanism of mineralization in cementoblasts under mechanical compression to improve orthodontic therapy. Autophagy has a protective role in maintaining cell homeostasis under environmental stress and was reported to be involved in the mineralization process. Long noncoding RNAs are important regulators of biological processes, but their functions in compressed cementoblasts during orthodontic tooth movement remain unclear. In this study, we showed that compressive force downregulated the expression of mineralization-related markers. LincRNA-p21 was strongly enhanced by compressive force. Overexpression of lincRNA-p21 downregulated the expression of mineralization-related markers, while knockdown of lincRNA-p21 reversed the compressive force-induced decrease in mineralization. Furthermore, we found that autophagy was impeded in compressed cementoblasts. Then, overexpression of lincRNA-p21 decreased autophagic activity, while knockdown of lincRNA-p21 reversed the autophagic process decreased by mechanical compression. However, the autophagy inhibitor 3-methyladenine abolished the lincRNA-p21 knockdown-promoted mineralization, and the autophagy activator rapamycin rescued the mineralization inhibited by lincRNA-p21 overexpression. Mechanistically, the direct binding between lincRNA-p21 and FoxO3 blocked the expression of autophagy-related genes. In a mouse orthodontic tooth movement model, knockdown of lincRNA-p21 rescued the impeded autophagic process in cementoblasts, enhanced cementogenesis, and alleviated orthodontic force-induced root resorption. Overall, compressive force-induced lincRNA-p21 inhibits the mineralization capability of cementoblasts by impeding the autophagic process.

The mechanism underlying arsenic-induced PD-L1 upregulation in transformed BEAS-2B cells.

Chronic exposure to arsenic promotes lung cancer. Human studies have identified immunosuppression as a risk factor for cancer development. The immune checkpoint pathway of Programmed cell death 1 ligand (PD-L1) and its receptor (programmed cell death receptor 1, PD-1) is the most studied mechanism of immunosuppression. We have previously shown that prolonged arsenic exposure induced cell transformation of BEAS-2B cells, a human lung epithelial cell line. More recently our study further showed that arsenic induced PD-L1 up-regulation, inhibited T cell effector function, and enhanced lung tumor formation in the mice. In the current study, using arsenic-induced BEAS-2B transformation as a model system we investigated the mechanism underlying PD-L1 up-regulation by arsenic. Our data suggests that Lnc-DC, a long non-coding RNA, and signal transducer and activator of transcription 3 (STAT3) mediates PD-L1 up-regulation by arsenic.

LncRNA PCAT6 activated by SP1 facilitates the progression of breast cancer by the miR-326/LRRC8E axis.

Breast cancer is an aggressive malignancy with high morbidity in females worldwide. Extensive studies reveal that long noncoding RNAs (lncRNAs) are abnormally expressed and act as key regulators in various cancers, including breast cancer. In this work, we investigated the role and regulatory mechanism of lncRNA prostate cancer-associated transcript 6 (PCAT6) in breast cancer progression. Our findings revealed that PCAT6 was overexpressed in breast cancer tissues and cell lines. Furthermore, elevation of PCAT6 reflected an adverse prognosis of patients. Functional experiments indicated that PCAT6 knockdown hampered cell proliferation, facilitated apoptosis and cell cycle arrest in vitro, and inhibited tumor growth in vivo. We also found that the transcription factor SP1 could bind to the PCAT6 promoter and promoted its expression. Subsequently, it was verified that PCAT6 was a molecular sponge for microRNA-326 (miR-326), and the leucine-rich repeat containing the eight family member E (LRRC8E) was a direct target of miR-326. Rescue assays revealed that LRRC8E overexpression attenuated the suppressive effect of PCAT6 knockdown on cellular progression of breast cancer. In summary, this study demonstrated that SP1-activated PCAT6 promoted the malignant behaviors of breast cancer cells by regulating the miR-326/LRRC8E axis.

Competitive endogenous RNA network and pathway-based analysis of LncRNA single-nucleotide polymorphism in myasthenia gravis.

Myasthenia gravis (MG) is a complex neurological autoimmune disease with a pathogenetic mechanism that has yet to be elucidated. Emerging evidence has revealed that genes, non-coding RNAs and genetic variants play significant roles in the pathogenesis of MG. However, the molecular mechanisms of single nucleotide polymorphisms (SNPs) located on lncRNAs could disturb lncRNA-mediated ceRNA regulatory functions still unclear in MG. In this study, we collated 276 experimentally confirmed MG risk genes and 192 MG risk miRNAs. We then constructed a lncRNA-mediated ceRNA network for MG based on multi-step computational strategies. Next, we systematically integrated risk pathways and identified candidate SNPs in lncRNAs for MG based on data acquired from public databases. In addition, we constructed a pathway-based lncRNA-SNP mediated network (LSPN) that contained 128 lncRNAs targeting 8 MG risk pathways. By analyzing network, we propose a latent mechanism for how the "lncRNA-SNP-mRNA-pathway" axis affects the pathogenesis of MG. Moreover, 25 lncRNAs and 51 SNPs on lncRNAs were extracted from the "lncRNA-SNP-mRNA-pathway" axis. Finally, functional analyses demonstrated lncRNA-SNPs mediated ceRNA regulation pairs associated with MG participated in the MAPK signaling pathway. In summary, we constructed MG-specific lncRNA-SNPs mediated ceRNA regulatory networks based on pathway in the present study, which was helpful to elucidate the roles of lncRNA-SNPs in the pathogenesis of MG and provide novel insights into mechanism of lncRNA-SNPs as potential genetic risk biomarkers of MG.

Tumor-Infiltrating Immune-Related Long Non-Coding RNAs Indicate Prognoses and Response to PD-1 Blockade in Head and Neck Squamous Cell Carcinoma.

Long non-coding RNAs (lncRNAs) in immune cells play critical roles in tumor cell-immune cell interactions. This study aimed to characterize the landscape of tumor-infiltrating immune-related lncRNAs (Ti-lncRNAs) and reveal their correlations with prognoses and immunotherapy response in head and neck squamous cell carcinoma (HNSCC). We developed a computational model to identify Ti-lncRNAs in HNSCC and analyzed their associations with clinicopathological features, molecular alterations, and immunotherapy response. A signature of nine Ti-lncRNAs demonstrated an independent prognostic factor for both overall survival and disease-free survival among the cohorts from Fudan University Shanghai Cancer Center, The Cancer Genome Atlas, GSE41613, and GSE42743. The Ti-lncRNA signature scores in immune cells showed significant associations with TP53 mutation, CDKN2A mutation, and hypoxia. Inferior signature scores were enriched in patients with high levels of PDCD1 and CTLA4 and high expanded immune gene signature (IGS) scores, who displayed good response to PD-1 blockade in HNSCC. Consistently, superior clinical response emerged in melanoma patients with low signature scores undergoing anti-PD-1 therapy. Moreover, the Ti-lncRNA signature was a prognostic factor independent of PDCD1, CTLA4, and the expanded IGS score. In conclusion, tumor-infiltrating immune profiling identified a prognostic Ti-lncRNA signature indicative of clinical response to PD-1 blockade in HNSCC.

FOXO3-induced oncogenic lncRNA CASC9 enhances gefitinib resistance of non-small-cell lung cancer through feedback loop.

Gefitinib is tyrosine kinase inhibitor of epidermal growth factor receptor, which exhibits notable clinical efficacy in non-small-cell lung cancer (NSCLC) treatment. However, gefitinib resistance is a critical obstacle for NSCLC targeted therapy. Here, we investigated the biological functions and mechanisms of lncRNA CASC9 in NSCLC gefitinib resistance. Screening analysis and RT-qPCR demonstrated that CASC9 was up-regulated in the gefitinib-resistant NSCLC cells (PC9/GR). Moreover, high-expression of CASC9 acted as an unfavorable factor for NSCLC patients. Functionally, CASC9 promoted the proliferation and gefitinib resistance of PC9/GR cells in vitro, and knockdown of CASC9 repressed the tumor growth in vivo. Mechanistically, CASC9 epigenetically promoted the FOXO3 expression via inhibiting miR-195-5p. In turn, transcription factor FOXO3 bound with the promoter region of CASC9 to enhance CASC9 transcriptional level, thereby forming CASC9/miR-195-5p/FOXO3 positive feedback loop. In conclusion, our research identified the regulation of CASC9/miR-195-5p/FOXO3 feedback loop on NSCLC gefitinib resistance, which might help researchers develop potential therapeutic targets for NSCLC.

Peripheral Blood-Based DNA Methylation of Long Non-Coding RNA H19 and Metastasis-Associated Lung Adenocarcinoma Transcript 1 Promoters are Potential Non-Invasive Biomarkers for Gastric Cancer Detection.

INTRODUCTION: The early diagnosis and detection could greatly improve the clinical outcome of gastric cancer (GC) patients. However, the non-invasive biomarkers for GC detection remain to be identified. METHOD: We used online databases (GEPIA, UALCAN, Kaplan-Meier plotter, TIMER, and MEXPRESS) to explore the association between H19 or metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) expression in tissues and the occurrence, development, prognosis, the levels of immune cell infiltration, and methylation of GC; the correlation between mRNA expression and DNA methylation levels of genes were also examined. Methylation levels of H19 or MALAT1 in peripheral blood were compared between 150 GC patients and 100 healthy controls (HCs). Predictive nomograms were constructed among female and male groups for GC diagnosis. The calibration curves, Hosmer-Lemeshow test, and decision curve analysis were also used to examine the nomograms' predictive ability and clinical values. RESULTS: Using multiple online databases, we found that the mRNA expressions of H19 and MALAT1 in tissues were related to the occurrence of GC, and such expressions were associated with immune cell infiltration of GC and negatively correlated with DNA methylation levels of H19 and MALAT1. H19 gene, H19C island, and MALAT1B island, as well as 20 CpG sites were hypermethylated in peripheral blood of GC patients compared with HCs; similar results were also found in female and male groups (P < .05 for all). The combination of H19c3, H19c4, MALAT1b12, and age, as well as the combination of H19b7, H19c1, H19c5, and age in the nomograms could distinguish GC patients from HCs in the female group and male group, respectively. CONCLUSION: We found statistically significant hypermethylation of H19 and MALAT1 promoters in GC patients, and meaningful sensitivity and specificity of MALAT1 and H19 methylation in discriminating GC and HCs were observed in both female and male groups, which indicates that the peripheral blood-based DNA methylation of H19 and MALAT1 could act as potential non-invasive biomarkers for the diagnosis of GC.

Long non-coding RNA FOXP4-AS1 is a prognostic biomarker and associated with immune infiltrates in ovarian serous cystadenocarcinoma.

BACKGROUND: FOXP4-AS1 expression participates in multiple signal pathways and has been previously reported in colorectal cancer, cervical cancer, and other cancer cells. However, its role on prognosis and immune infiltrates in ovarian serous cystadenocarcinoma (OVs) remains unclear. The purpose of our study was to investigate the expression of FOXP4-AS1 in OVs and its association with immune infiltrates, and determined its prognostic roles in OVs. METHODS: Using The Cancer Genome Atlas (TCGA) database, we retrieved FOXP4-AS1 expression and clinical information for 376 patients with OVs. Wilcoxon rank sum test was used to compare the expression of FOXP4-AS1 in OVs and normal ovarian tissue. Logistic regression was used to analyze the relationship between clinicopathologic features and FOXP4-AS1. Gene Set Enrichment Analysis (GSEA), and single sample Gene Set Enrichment Analysis (ssGSEA) was conducted to investigate the enrich pathways and functions and quantify the extent of immune cells infiltration for FOXP4-AS1. Kaplan-Meier method was used to generate survival curves, and Cox regression was used to analyze the relationship between FOXP4-AS1 and survival rate. RESULTS: High FOXP4-AS1 expression was significantly correlated with tumor FIGO stage (P = .026). Multivariate survival analysis showed that FOXP4-AS1was an independent prognostic marker for overall survival (OS; hazard ratio [HR]: 0.638; 95% confidence interval [CI]:0.467-0.871; P = .001) and disease-specific survival (DSS; HR: 0.649; CI: 0.476-0.885; P = .006). GSEA showed that High FOXP4-AS1 expression may active programmed cell death 1 (PD-1) signaling, the cytotoxic T lymphocyte-associated antigen-4 (CTLA4) pathway, the B cell receptor signaling pathway, apoptosis, fibroblast growth factor receptor (FGFR) signaling, and the Janus-activated kinase signal transducers and activators of transcription (JAK-STAT) signaling pathway. FOXP4-AS1 expression was negatively correlated with markers of immune cells, including aDC, cytotoxic cells and neutrophils. CONCLUSION: High FOXP4-AS1 expression has the potential to be a prognostic molecular marker of favorable survival in OVs.

Epigenetic Mechanisms in Type 2 Diabetes Retinopathy: A Systematic Review.

Diabetic retinopathy (DR) is one of the main causes of vision loss in middle-aged economically active people. Modifiable (i.e., hyperglycaemia, hypertension, hyperlipidaemia, obesity, and cigarette smoke) and non-modifiable factors (i.e., duration of diabetes, puberty, pregnancy and genetic susceptibility) are involved in the development of DR. Epigenetic mechanisms, modulating the oxidative stress, inflammation, apoptosis, and aging, could influence the course of DR. Herein, we conducted a systematic review of observational studies investigating how epigenetics affects type 2 diabetes retinopathy (T2DR). A total of 23 epidemiological studies were included: 14 studies focused on miRNA, 4 studies on lnc-RNA, one study on both miRNA and lnc-RNA, and 4 studies on global or gene-specific DNA methylation. A direct relation between the dysregulation of miR-21, miR-93, and miR-221 and FPG, HbA1c, and HOMA-IR was identified. A panel of three miRNAs (hsa-let-7a-5p, hsa-miR-novel-chr5_15976, and hsa-miR-28-3p) demonstrated a good sensitivity and specificity for predicting T2DR. Little evidence is available regarding the possible role of the long non-coding MALAT1 dysregulation and MTHFR gene promoter hypermethylation. Despite these initial, encouraging findings potentially suggesting a role of epigenetics in T2DR, the use in clinical practice for the diagnosis and staging of this complication encounters several difficulties and further targeted investigations are still necessary.