LncRNA TP73-AS1 accelerates tumor progression in gastric cancer through regulating miR-194-5p/SDAD1 axis. Pathol Res Pract. 2018;214:1993-1999. [PMID: 30279010 DOI: 10.1016/j.prp.2018.09.006]

The prognostic, diagnostic, and therapeutic impact of Long noncoding RNAs in gastric cancer

Gastric cancer (GC), ranking as the third deadliest cancer globally, faces challenges of late diagnosis and limited treatment efficacy. Long non-coding RNAs (lncRNAs) emerge as valuable treasured targets for cancer prognosis, diagnosis, and therapy, given their high specificity, convenient non-invasive detection in body fluids, and crucial roles in diverse physiological and pathological processes. Research indicates the significant involvement of lncRNAs in various aspects of GC pathogenesis, including initiation, metastasis, and recurrence, underscoring their potential as novel diagnostic and prognostic biomarkers, as well as therapeutic targets for GC. Despite existing challenges in the clinical application of lncRNAs in GC, the evolving landscape of lncRNA molecular biology holds promise for advancing the survival and treatment outcomes of gastric cancer patients. This review provides insights into recent studies on lncRNAs in gastric cancer, elucidating their molecular mechanisms and exploring the potential clinical applications in GC.

TP73-AS1 rs3737589 Polymorphism is Associated With the Clinical Stage of Colorectal Cancer

Objective

TP73-AS1 can promote the occurrence and development of a variety of tumors, including colorectal cancer (CRC). The current study aimed to investigate the association between a potentially functional genetic polymorphism (rs3737589 T > C) on the TP73-AS1 gene and the susceptibility and clinical stage of CRC in a Chinese Han population.

Methods

The polymorphic genotyping was performed by the SNaPshot method. The real-time quantitative PCR method and the luciferase assay were used separately to explore genotype-tissue expression and the function of the genetic polymorphism.

Results

A total of 576 CRC patients and 896 healthy controls were included in the current study. The rs3737589 polymorphism was not associated with CRC susceptibility but was associated with the CRC stage (CC vs. TT: OR = 0.25, 95% CI = 0.12 - 0.54, P=0.0003; C vs. T: OR = 0.69, 95% CI = 0.53-0.89, P=0.006; and CC vs. (TC + TT): OR = 0.26, 95% CI = 0.12-0.56, P=0.0004). CRC patients carrying the rs3737589 CC genotype or C allele were less likely to have stage III/IV tumors than those carrying the rs3737589 TT genotype or T allele. The expression of TP73-AS1 was lower in CRC tissues with the rs3737589 CC genotype compared to those with the TT genotype. Bioinformatics analysis and the luciferase assay revealed that the C allele could promote the binding of miR-3166 and miR-4771 to TP73-AS1.

Conclusion

The TP73-AS1 gene rs3737589 polymorphism affecting miRNAs binding is associated with the CRC stage and may serve as a biomarker for predicting CRC progression.

circFCHO2 promotes gastric cancer progression by activating the JAK1/STAT3 pathway via sponging miR-194-5p

circFCHO2 has been revealed to be overexpressed in gastric cancer (GC) patients. This article identified the function of circFCHO2 on GC progression. The expression of circFCHO2, miR-194-5p and JAK1 in 30 GC patients and cells was monitored by quantitative reverse transcription-polymerase chain reaction. circFCHO2 localization in GC cells was monitored by RNA fluorescence in situ hybridization. Cell counting kit-8 assay, 5-ethynyl-2-deoxyuridine staining, transwell experiment, tube formation and sphere formation experiments were applied to detect GC cell proliferation, invasion, angiogenesis and cancer stem cell characteristics. Dual-luciferase reporter gene assay, RNA pull down assay and RNA immunoprecipitation experiment were utilized to research the binding between two genes. In vivo tumorigenesis and lung metastasis were studied using nude mice. Immunohistochemistry and hematoxylin-eosin staining were conducted. Protein expression was assessed by Western blot. Serum exosomes of GC patients and healthy participants were isolated. circFCHO2 up-modulation in GC patients was related to poor outcome. circFCHO2 was located in the cytoplasm of GC cells. circFCHO2 silencing weakened the proliferation, invasion, angiogenesis and stem cell characteristics of GC cells. miR-194-5p knockdown counteracted this effect. circFCHO2 activated the JAK1/STAT3 pathway by sponging miR-194-5p. miR-194-5p overexpression attenuated the malignant phenotypes of GC cells. JAK1 overexpression abrogated this effect. circFCHO2 silencing weakened GC cells growth and lung metastasis in vivo. circFCHO2 was up-modulated in serum exosomes of GC patients. circFCHO2 was an oncogene in GC by activating the JAK1/STAT3 pathway via sponging miR-194-5p. circFCHO2 might be a novel target and diagnostic marker for GC.

TP73-AS1 as a predictor of clinicopathological parameters and prognosis in human malignancies: a meta and bioinformatics analysis

Background

Long non-coding RNA P73 antisense RNA 1 T (non-protein coding), also known as Lnc RNA TP73-AS1, is dysregulated in various tumors but the correlation between its expression and clinicopathological parameters and/or prognoses in cancer patients is inconclusive. Here, we performed a meta-analysis to evaluate the prognostic value of Lnc RNA TP73-AS1 for malignancies.

Methods

We systematically searched four online databases including PubMed, the Web of Science, Embase, and the Cochrane Library for eligible articles published up to June 29/2020. Odds ratios (ORs) and Pooled hazard ratios (HRs) with 95% confidence intervals (95% CIs) were used to assess the association of TP73-AS1 expression with prognostic and clinicopathological parameters. We further validated TP73-AS1 expression in various malignancies and its potential prognostic value using the GEPIA online database. We predicted potential biological processes and relevant signal mechanisms through the public databases.

Results

A total of 26 studies examining 14 cancers were analyzed to evaluate the relationship between TP73-AS1 expression, clinicopathological features and prognostic indicators. The results indicated that TP73-AS1 expression markedly correlates with TNM stage (OR = 3.27,95% CI:2.43–4.39, P < 0.00001), tumor size (OR = 3.00, 95%CI:2.08–4.35, P < 0.00001), lymph node metastasis (OR = 2.77, 95%CI:1.42–5.38,P < 0.00001) and distant metastasis (OR = 4.50,95%CI:2.

62–7.73,P < 0.00001). No correlation with age (OR = 1.12,95%CI:0.77–1.64, P > 0.05), gender (OR = 1.08, 95%CI:0.84–1.38, P > 0.05) or differentiation (OR = 1.39, 95%CI:0.71–2.70, P = 0.340) was observed. TP73-AS1 overexpression was a biomarker of poor Overall survival(OS)(HR = 1.85,95%CI:1.53–2.22, P < 0.00001) and Disease-Free-Survival (DFS) (HR = 1.57,95%CI:1.03–2.42, P < 0.05). Dysregulated TP73-AS1 expression and its prognostic value in various cancers was validated based on The Cancer Genome Atlas (TCGA). Further biological function predictions indicated that TP73-AS1 was involved in pro-oncogenic signaling.

Conclusions

The upregulation of Lnc RNA TP73-AS1 was related to detrimental clinicopathological parameters and can be considered an indicator of poor prognosis for cancer malignancies.

NAP1L5 Promotes Nucleolar Hypertrophy and Is Required for Translation Activation During Cardiomyocyte Hypertrophy

Pathological growth of cardiomyocytes during hypertrophy is characterized by excess protein synthesis; however, the regulatory mechanism remains largely unknown. Using a neonatal rat ventricular myocytes (NRVMs) model, here we find that the expression of nucleosome assembly protein 1 like 5 (Nap1l5) is upregulated in phenylephrine (PE)-induced hypertrophy. Knockdown of Nap1l5 expression by siRNA significantly blocks cell size enlargement and pathological gene induction after PE treatment. In contrast, Adenovirus-mediated Nap1l5 overexpression significantly aggravates the pro-hypertrophic effects of PE on NRVMs. RNA-seq analysis reveals that Nap1l5 knockdown reverses the pro-hypertrophic transcriptome reprogramming after PE treatment. Whereas, immune response is dominantly enriched in the upregulated genes, oxidative phosphorylation, cardiac muscle contraction and ribosome-related pathways are remarkably enriched in the down-regulated genes. Although Nap1l5-mediated gene regulation is correlated with PRC2 and PRC1, Nap1l5 does not directly alter the levels of global histone methylations at K4, K9, K27 or K36. However, puromycin incorporation assay shows that Nap1l5 is both necessary and sufficient to promote protein synthesis in cardiomyocyte hypertrophy. This is attributable to a direct regulation of nucleolus hypertrophy and subsequent ribosome assembly. Our findings demonstrate a previously unrecognized role of Nap1l5 in translation control during cardiac hypertrophy.

Curcumin suppresses the progression of gastric cancer by regulating circ_0056618/miR-194-5p axis

Curcumin has been demonstrated to be an anti-tumor agent in many types of cancers, including gastric cancer (GC). However, the molecular mechanisms by which curcumin performs its anti-tumor effects remain elusive. circ_0056618 and miR-194-5p are reported to be involved in GC progression, but their relationships with curcumin are unclear. In this study, circ_0056618 was elevated, and miR-194-5p was reduced in GC tissues and cells. Curcumin treatment led to a decrease in circ_0056618 level in GC cells. Overexpression of circ_0056618 promoted cell proliferation, migration, and invasion and suppressed cell cycle arrest and apoptosis in curcumin-treated GC cells. Moreover, miR-194-5p was identified as the target of circ_0056618, and its expression in GC cells increased after curcumin treatment. Overexpression of miR-194-5p reversed the promotional effect of circ_0056618 on cell progression in curcumin-treated GC cells. Additionally, curcumin treatment repressed the tumorigenesis of GC in vivo through regulating circ_0056618. Curcumin treatment delayed the development of GC partly through decreasing circ_0056618 and increasing miR-194-5p.

Roles of ncRNAs as ceRNAs in Gastric Cancer

Although ignored in the past, with the recent deepening of research, significant progress has been made in the field of non-coding RNAs (ncRNAs). Accumulating evidence has revealed that microRNA (miRNA) response elements regulate RNA. Long ncRNAs, circular RNAs, pseudogenes, miRNAs, and messenger RNAs (mRNAs) form a competitive endogenous RNA (ceRNA) network that plays an essential role in cancer and cardiovascular, neurodegenerative, and autoimmune diseases. Gastric cancer (GC) is one of the most common cancers, with a high degree of malignancy. Considerable progress has been made in understanding the molecular mechanism and treatment of GC, but GC’s mortality rate is still high. Studies have shown a complex ceRNA crosstalk mechanism in GC. lncRNAs, circRNAs, and pseudogenes can interact with miRNAs to affect mRNA transcription. The study of the involvement of ceRNA in GC could improve our understanding of GC and lead to the identification of potential effective therapeutic targets. The research strategy for ceRNA is mainly to screen the different miRNAs, lncRNAs, circRNAs, pseudogenes, and mRNAs in each sample through microarray or sequencing technology, predict the ceRNA regulatory network, and, finally, conduct functional research on ceRNA. In this review, we briefly discuss the proposal and development of the ceRNA hypothesis and the biological function and principle of ceRNAs in GC, and briefly introduce the role of ncRNAs in the GC’s ceRNA network.

LINC01436 Inhibited miR-585-3p Expression and Upregulated MAPK1 Expression to Promote Gastric Cancer Progression

BACKGROUND

Gastric cancer (GC) is a prevalent type of digestion system malignancies. Dysregulation of long non-coding RNAs (lncRNAs) has been proven to be prognostic factors and biological regulators in human cancers.

AIMS

The current study aimed to explore the role of long intergenic non-protein coding RNA 1436 (LINC01436) and its underlying mechanism in the progression of GC.

METHODS

RT-qPCR was conducted to measure RNA expression. Western blot was used for exploration of protein level. CCK-8, caspase-3 activity, and transwell assays were applied to evaluate the proliferative, apoptotic, and migratory abilities of GC cells, respectively. Mechanical experiments were used to probe the molecular interplay between genes.

RESULTS

High LINC01436 level suggested low overall survival in GC patients, and LINC01436 was highly expressed in GC tissues and cells. Besides, LINC01436 knockdown hampered cell proliferation and migration, while facilitated cell apoptosis. Mechanistically, LINC01436 upregulated mitogen-activated protein kinase 1 (MAPK1) expression by competitively binding with miR-585-3p and inhibiting miR-585-3p expression. Furthermore, LINC01436 negatively regulated miR-585-3p expression by enhancing the zeste 2 polycomb repressive complex 2 subunit (EZH2)-induced trimethylation of histone H3 at lysine 27 (H3K27me3) on miR-585-3p promoter. Final rescue assays revealed that overexpression of MAPK1 could rescue the suppressive influence of LINC01436 depletion on GC progression.

CONCLUSIONS

LINC01436 epigenetically silences miR-585-3p and acts as miR-585-3p to upregulate MAPK1 expression and promote GC progression.

Knockdown of TPT1-AS1 inhibits cell proliferation, cell cycle G1/S transition, and epithelial-mesenchymal transition in gastric cancer

Long non-coding RNAs are considered to be critical regulators of tumor progression. Tumor protein translationally controlled 1 antisense RNA 1 (TPT1-AS1) was shown to have an oncogenic role in cervical and ovarian cancer. The clinical significance and biological function of TPT1-AS1 in gastric cancer (GC) are not clear. In this study, we analyzed the expression of TPT1-AS1 in GC tissues and cell lines and performed functional and mechanistic analysis of TPT1-AS1 effects on GC cell proliferation, migration, and invasion. TPT1-AS1 expression was determined in 76 pairs of GC tissues vs. matched adjacent normal tissues and in four GC cell lines (SGC-7901, AGS, BGC-823, and MGC-803) vs. GES-1 cell line by quantitative reverse transcription PCR. SGC-7901 and MGC-803 cells were transfected with small interfering RNA or scrambled negative control, and cell proliferation, colony formation, migration, invasion and cell cycle assays were performed. The expression of proteins involved in cell cycle progression and epithelial-mesenchymal transition was analyzed by Western blot. TPT1-AS1 expression was significantly higher in GC tissues and cell lines compared to controls. The overexpression of TPT1-AS1 was significantly correlated with TNM stage and lymph node metastasis, and it was associated with worse prognosis of GC patients according to the Kaplan-Meier survival analysis and Cox proportional hazard regression analysis. The knockdown of TPT1-AS1 significantly inhibited proliferation, cell cycle G1/S transition, migration, and invasion of SGC-7901 and MGC-803 cells. Moreover, TPT1-AS1 knockdown downregulated the expression of cyclin-dependent kinase (CDK) 4, cyclin D1, and vimentin and upregulated the expression of p21 and E-cadherin. Our findings suggest that TPT1-AS1 may be a promising therapeutic target in GC.

Long Noncoding RNAs in Gastrointestinal Cancer: Tumor Suppression Versus Tumor Promotion

Approximately 80% of the human genome harbors biochemical marks of active transcription that its majority transcribes to noncoding RNAs, namely long noncoding RNAs (lncRNAs). LncRNAs are heterogeneous RNA transcripts that regulate critical biological processes such as cell survival and death. They involve in the progression of different cancers by affecting transcriptional and post-transcriptional modifications as well as epigenetic control of numerous tumor suppressors and oncogenes. Recent findings show that aberrant expression of lncRNAs is associated with tumor initiation, progression, invasion, and overall survival of patients with gastrointestinal (GI) cancers. Some lncRNAs play as tumor suppressors in all GI cancers, but others play as tumor promoters. However, some other lncRNAs might function as a tumor suppressor in one GI cancer, but as a tumor promoter in another GI cancer type. This fact highlights possible context dependency of the expression patterns and roles of at least some lncRNAs in GI cancer development and progression. Here, we review the functional relation of lncRNAs involved in the development and progression of GI cancer by focusing on their roles as tumor suppressor and tumor promoter genes.

Research Progress and Application Prospects of Long Noncoding RNAs in Gastric Neoplasms

Long noncoding RNAs (lncRNAs) are noncoding RNAs longer than 200 nt that have almost no function for encoding proteins. As an important regulatory molecule of the human genome, lncRNAs play a regulatory role in the human body. LncRNAs have a variety of functions, such as signaling, guiding, baiting or scaffolding of functional proteins, and are closely related to tumor development. Gastric cancer is one of the most common malignant tumors. It has a high incidence, a low early diagnosis rate, and a poor prognosis, and it seriously threatens human health. Abnormal expression of lncRNAs can affect the occurrence, development, invasion and metastasis of gastric cancer. Therefore, lncRNAs are expected to become important biomarkers and new targets for the diagnosis and treatment of gastric cancer. LncRNAs have a significant potential to guide the diagnosis, treatment and prognosis of gastric cancer. This article reviews lncRNAs and the mechanisms that have been discovered in recent years related to gastrointestinal tumors.

Long noncoding RNA CA3-AS1 suppresses gastric cancer migration and invasion by sponging miR-93-5p and targeting BTG3

The long noncoding RNAs (lncRNAs) are a class of noncoding RNAs that are broadly expressed in various biological cells and function in regulating gene expression. However, the function of lncRNAs and the role of lncRNAs in gastric cancer remain to be determined. Herein, the function of lncRNA CA3-AS1 was investigated in gastric cancer. Firstly, we found that the expression level of CA3-AS1 was decreased in gastric cancer cell lines and tissues. Then, CA3-AS1 overexpression inhibited the gastric cancer cells migration and invasion and knockdown of CA3-AS1 enhanced the gastric cancer cells migration and invasion. Moreover, FISH assays and qPCR results revealed that CA3-AS1 was mainly expressed in the cytoplasm of gastric cancer cells. Then, the relationship between CA3-AS1 and miR-93-5p was explored. Luciferase reporter assays results showed that miR-93-5p was a direct target of CA3-AS1 in SGC-7901 and BCG-823. Furthermore, BTG3 was identified as a direct target gene of miR-93-5p. Restore experiments showed that CA3-AS1 upregulated the expression level of BTG3 and inhibited the gastric cancer cells invasion by sponging miR-93-5p. Finally, we found that CA3-AS1 inhibited the metastasis ability of gastric cancer cells in vivo. Above results suggested that CA3-AS1 acted as anti-oncogene in gastric cancer and might become a vital target for clinical treatment.

Role of long non-coding RNA TP73-AS1 in cancer

Cancer incidence rate has increased so much that it is the second leading cause of deaths worldwide after cardiovascular diseases. Sensitive and specific biomarkers are needed for an early diagnosis of cancer and in-time treatment. Recent studies have found that long non-coding RNAs (lncRNAs) participate in cancer tumorigenesis. LncRNA P73 antisense RNA 1T (TP73-AS1), also known as KIAA0495 and p53-dependent apoptosis modulator (PDAM), is located in human chromosomal band 1p36.32 and plays a crucial role in many different carcinomas. This review summarizes current findings on the role of TP73-AS1 and its signaling pathways in various cancers, including glioma, esophageal squamous cell carcinoma (ESCC), hepatocellular carcinoma (HCC), colorectal cancer (CRC), osteosarcoma, gastric cancer (GC), clear cell renal cell carcinoma (ccRCC), breast cancer (BC), bladder cancer, ovarian cancer, cholangiocarcinoma (CCA), lung cancer, and pancreatic cancer. Its aberrant expression generally correlates with clinicopathological characterization of patients. Moreover, TP73-AS1 regulates proliferation, migration, invasion, apoptosis, and chemoresistance cancer mechanisms, both in vivo and in vitro, through different signaling pathways. Therefore, TP73-AS1 may be considered as a marker for diagnosis and prognosis, also as a target for cancer treatment.

Retracted: Long non-coding RNA TP73-AS1 facilitates progression and radioresistance in lung cancer cells by the miR-216a-5p/CUL4B axis with exosome involvement

Retraction: Qiu, H., Zhang, L., Yi, T., Yang, K., Gong, Y. and Xie, C. (2020), Long non‐coding RNA TP73‐AS1 facilitates progression and radioresistance in lung cancer cells by the miR‐216a‐5p/CUL4B axis with exosome involvement. Thorac Cancer. https://doi.org/10.1111/1759-7714.13602

The above article, published online on 25 August 2020 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement among the authors, the journal Editor in Chief Qinghua Zhou, and John Wiley & Sons Ltd. The retraction has been agreed after the results reported in Figures 3B, 3C, 3I, and 3J were found to be not repeatable in authors' further study.

Prognostic value and therapeutic potential of the long noncoding RNA TP73-AS1 in cancers: A systematic review and meta-analysis

Studies published in recent years have demonstrated that abnormal long noncoding RNA (lncRNA) antisense RNA to TP73 gene (TP73-AS1) expression is markedly associated with tumorigenesis, cancer progression and the prognosis of cancer patients. We aimed to explore the prognostic value of TP73-AS1 in multiple cancers. We comprehensively searched PubMed, Embase, Web of Science and the Cochrane Library (up to February 21, 2019). Hazard ratios (HRs), odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs) were calculated to estimate the association of TP73-AS1 with survival and clinicopathological features. The potential targets and pathways of TP73-AS1 in multiple cancers were summarized. Nineteen studies that involved thirteen types of cancers and 1329 cancer patients were identified as eligible for this meta-analysis. The results showed that high TP73-AS1 expression was significantly correlated with shorter overall survival (OS) (HR = 1.962, 95% CI 1.630-2.362) and disease-free survival (DFS) (HR = 2.050, 95% CI 1.293-3.249). The summary HRs of OS were 2.101 (95% CI 1.516-2.911) for gastric cancer (GC) and 1.920 (95% CI 1.253-2.942) for osteosarcoma. Subgroup analysis of OS demonstrated that the differential expression of TP73-AS1 in cancer tissues was a potential source of heterogeneity. Furthermore, increased TP73-AS1 expression was markedly associated with larger tumor size (OR = 2.759, 95% CI 1.759-4.330), advanced histological grade (OR = 2.394, 95% CI 1.231-4.656), lymph node metastasis (OR = 2.687, 95% CI 1.211-5.962), distant metastasis (OR = 4.145, 95% CI 2.252-7.629) and advanced TNM stage (OR = 2.633, 95% CI 1.507-4.601). The results of Egger's test and sensitivity analysis verified the robustness of the original results. High TP73-AS1 expression can predict poor survival and poor clinicopathological features in cancer patients and TP73-AS1 might be a potential biomarker and therapeutic target.

LINC00667 promotes Wilms' tumor metastasis and stemness by sponging miR-200b/c/429 family to regulate IKK-β

Wilms' tumor, also known as nephroblastoma, is a kind of pediatric renal cancer. Previous studies have indicated that microRNAs (miRNAs) regulate various cancers progression. However, whether miR-200 family regulated Wilms' tumor progression remains to be elucidated. In our study, miR-200b/c/429 expression was downregulated in Wilms' tumor tissue samples from 25 patients. And data from three independent analyses of quantitative real-time polymerase chain reaction revealed that the expression of miR-200b/c/429 was downregulated in Wilms' tumor cell lines. Functionally, Cell counting kit-8 assay revealed that cell viability was reduced by overexpressing miR-200b/c/429. Transwell assay manifested that cell migration and invasion was hindered by miR-200b/c/429 overexpression. Sphere-forming and western blot assays demonstrated that miR-200b/c/429 overexpression suppressed the sphere formation ability. Mechanically, nuclear factor-κB (NF-κB) pathway was confirmed to be associated with Wilms' tumor progression; miR-200b/c/429 overexpression inactivated NF-κB pathway as miR-200b/c/429 was identified to target IκB kinase β (IKK-β), an NF-κB pathway-related gene. Moreover, miR-200b/c/429 was sponged by LINC00667 in Wilms' tumor cells. LINC00667 competitively bound with miR-200b/c/429 to regulate IKK-β expression and then activated NF-κB pathway in Wilms' tumor. Subsequently, rescue assays illustrated that silencing of IKK-β could reverse the effect of miR-200b/c/429 inhibition on the progression of sh-LINC00667-transfected Wilms' tumor cells. In summary, LINC00667 promoted Wilms' tumor progression by sponging miR-200b/c/429 family to regulate IKK-β.

LncRNA PSMB8-AS1 acts as ceRNA of miR-22-3p to regulate DDIT4 expression in glioblastoma

Glioblastoma (GBM) is known to be one of the most fatal malignanies in central nerve system. Unfortunately, the therapies for glioblastoma still calls for further improvements. Increasing evidences have shown that the aberrant expression of long non-coding RNAs (lncRNAs) is highly relevant to glioma tumorigenesis and prognosis of GBM patients. High expression trends of lncRNA PSMB8-AS1 was observed in both glioblastoma tissues and cells. In return, GBM cell proliferation, apoptosis and radioresistance were regulated by PSMB8-AS1. In the meantime, PSMB8-AS1 mainly located in cytoplasm of glioblastoma cells, indicating post-transcriptional regulation. MiRNA-22-3p was found to contain potential binding site with PSMB8-AS1. On the other hand, low expression of miR-22-3p was exhibited in glioblastoma tissues and cells. Besides, PSMB8-AS1 and miR-22-3p had mutual suppression on the expression of each other in GBM cells. Furthermore, overexpression of PSMB8-AS1 promoted the level of DDIT4 through inhibiting miR-22-3p. Rescue assays demonstrated that overexpression of DDIT4 counteracted the impact of proliferation, apoptosis and radioresistance silencing PSMB8-AS1 lay on glioblastoma cell. Taken together, lncRNA PSMB8-AS1 acts as miR-22-3p sponge to mediate DDIT4 expression and regulate glioblastoma progression. PSMB8-AS1 might become a therapeutic target in the future.

Association of TP73-AS1 gene polymorphisms with the risk and survival of gastric cancer in a Chinese Han Population

It was investigated that TP73-AS1(TP73 antisense RNA 1) could function as an oncogene in gastric cancer (GC). The expression and function of long noncoding RNAs (lncRNAs) could be impacted by single nucleotide polymorphisms (SNPs), which are related to cancer susceptibility and prognosis. This study was to reveal the association between lncRNAs TP73-AS1 polymorphisms (rs1181865 A > G, rs9800 G > C, rs3737589 A > G, rs2298222 G > A, rs7515164 C > A) and GC in 1000 GC cases and 1000 controls in a Chinese Han population. Rs3737589 G allele had significant associations with the increasing risk of GC (G vs. A: p = .005). Rs3737589 variant genotypes (AG + GG) were related to an increased risk of GC in the elder population (age ≥60), females, nonsmokers, nondrinkers, individuals living in urban, and individuals without family history of GC in stratified analyses. Rs3737589 variant genotypes (AG + GG) were related to the advanced depth of tumor invasion (T3 + T4). Besides, we found that GC patients with AG or GG genotype of rs3737589 had poorer overall survival (OS) than those with AA genotype (p < .05). Our findings showed that the lncRNA TP73-AS1 rs3737589 polymorphism might increase the risk of GC, and rs3737589 polymorphism could be a potential biomarker to predict the prognosis of GC patients.

Activation of Hypoxia-Inducible Factor Signaling Modulates the RNA Protein Interactome in Caenorhabditis elegans

The cellular response to hypoxia is crucial to organismal survival, and hypoxia-inducible factors (HIF) are the key mediators of this response. HIF-signaling is central to many human diseases and mediates longevity in the nematode. Despite the rapidly increasing knowledge on RNA-binding proteins (RBPs), little is known about their contribution to hypoxia-induced cellular adaptation. We used RNA interactome capture (RIC) in wild-type Caenorhabditis elegans and vhl-1 loss-of-function mutants to fill this gap. This approach identifies more than 1,300 nematode RBPs, 270 of which can be considered novel RBPs. Interestingly, loss of vhl-1 modulates the RBPome. This difference is not primarily explained by protein abundance suggesting differential RNA-binding. Taken together, our study provides a global view on the nematode RBPome and proteome as well as their modulation by HIF-signaling. The resulting RBP atlas is also provided as an interactive online data mining tool (http://shiny.cecad.uni-koeln.de:3838/celegans_rbpome).

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RNA interactome capture in wild-type C. elegans and vhl-1 loss-of-function mutants

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Identification of 1,354 nematode RBPs, 270 of which can be considered novel RBPs

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The modulation of the RBPome by vhl-1 is primary explained by differential RNA-binding

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The resulting RBP atlas is provided as an interactive online data mining tool

Knockdown Of Long Non-Coding RNA TP73-AS1 Inhibited Cell Proliferation And Metastasis Through Wnt/β-Catenin Pathway In Lung Adenocarcinoma

Background

Various evidences showed that abnormally expressed long non-coding RNAs (lncRNAs) play important roles in the tumorigenesis and progression of malignancies. However, the exact role and regulatory mechanism of lncRNA TP73-AS1 in the pathogenesis and progression of lung adenocarcinoma remain to be further elucidated.

Purpose

The aim of this study was to investigate the functional role and underlying mechanism of lncRNA TP73-AS1 in lung adenocarcinoma progression.

Methods

RT-PCR assay was employed to detect TP73-AS1 expression in lung adenocarcinoma tissues and cells. The function of TP73-AS1 in lung adenocarcinoma progression was estimated by MTT assay, EdU assay, flow cytometry, Western blot, wound-healing assay and transwell assay.

Results

LncRNA TP73-AS1 expression was significantly increased in lung adenocarcinoma tissues and cell lines. Moreover, functional assays revealed that silencing of lncRNA TP73-AS1 could attenuate cell proliferation, migration, invasion and epithelial–mesenchymal transition of lung adenocarcinoma, while enhanced expression of lncRNA TP73-AS1 led to the opposite results. Additionally, lncRNA TP73-AS1 knockdown could facilitate cell apoptosis and overexpression of lncRNA TP73-AS1 inhibited cell apoptosis. In addition, we further determined that lncRNA TP73-AS1 regulated cell metastasis through inducing the activation of Wnt/β-catenin signaling pathway in lung adenocarcinoma.

Conclusion

Our results indicated that lncRNA TP73-AS1 may play an oncogenic role in lung adenocarcinoma progression, which provided a promising therapy strategy for the treatment of lung adenocarcinoma.

Long noncoding RNA TP73-AS1 in human cancers

Long noncoding RNAs (lncRNAs) play an important role in tumor development. With the development of sequencing technology, many new lncRNAs have been discovered. lncRNA TP73-AS1 is abnormally expressed in many cancers. A summary of the current literature related to TP73-AS1 reveals that TP73-AS1 mainly regulates the occurrence and development of tumors through the mechanism of competitive endogenous RNA (ceRNA). In addition, the abnormal expression of TP73-AS1 can regulate the malignant function of tumor cells through a variety of possible mechanisms. All evidence suggests that TP73-AS1 may be a potential diagnostic biomarker or a new cancer therapeutic target.

Differentially expressed long noncoding RNAs and regulatory mechanism of LINC02407 in human gastric adenocarcinoma

BACKGROUND

Long noncoding RNAs (lncRNAs) have been identified to play important roles in the development and progression of various tumors, including gastric cancer (GC). However, the molecular role of lncRNAs in GC progression remains unclear.

AIM

To investigate the differential expression of lncRNAs in human GC and elucidate the function and regulatory mechanism of LINC02407.

METHODS

The Cancer Genome Atlas database was used to investigate the involvement of lncRNAs in GC. Quantitative real-time polymerase chain reaction was used to estimate the relative expression level of LINC02407 in GC tissues and cells. Functional experiments including CCK8 assay, apoptosis assay, wound healing assay, and transwell assay were used to investigate the effect of LINC02407 on GC cells. Some microRNAs were predicted and verified via bioinformatics analysis and the luciferase reporter system. Predictive analysis and Western blot assay were used to analyze the expression of related proteins.

RESULTS

Many differentially expressed lncRNAs were identified in GC, and some of them including LINC02407 can affect the survival. LINC02407 was upregulated in tumor tissues compared with adjacent tissues. HGC-27 cells showed the highest LINC02407 expression and HaCaT cells exhibited the lowest expression. Different experiment groups were constructed using LINC02407 overexpressing plasmids and related siRNAs. The results of functional experiments showed that LINC02407 can promote the proliferation, migration, and invasion of GC cells but inhibit apoptosis. Luciferase reporter assay showed that hsa-miR-6845-5p and hsa-miR-4455 was downstream regulated by LINC02407. Western blot analysis showed that adhesion G protein-coupled receptor D1 (ADGRD1) was regulated by the LINC02407-miR-6845-5p/miR-4455-ADGRD1 pathways.

CONCLUSION

LINC02407 plays a role in GC through the LINC02407-miR-6845-5p/miR-4455-ADGRD1 pathways, and thus, it may be an important oncogene and has potential value in GC diagnosis and treatment.

MiR-1193 was sponged by LINC00963 and inhibited cutaneous squamous cell carcinoma progression by targeting SOX4

Cutaneous squamous cell carcinoma (CSCC), a class of skin tumor derived from epidermal keratinocyte, is reputed as one of the most malignant tumors globally. MicroRNAs (miRNAs) are increasingly identified as essential players in CSCC. Current study aimed to uncover the impact and mechanism of miR-1193 in CSCC. We identified the low expression of miR-1193 in CSCC cell lines. Gain- and loss-of-function assays showed that miR-1193 acted as an inhibitor of proliferation and migration in CSCC cells. Furthermore, we illustrated that miR-1193 targeted and inhibited SRY-box 4 (SOX4), and that long intergenic non-protein coding RNA 963 (LINC00963) sponged miR-1193 to upregulate SOX4 expression. Rescue assays showed that LINC00963 regulated CSCC progression through miR-1193/SOX4 axis. In conclusion, our study firstly revealed the LINC00963/miR-1193/SOX4 axis in CSCC, indicating miR-1193 as a promising biological target in CSCC progression.

LncRNA TP73-AS1 sponges miR-141-3p to promote the migration and invasion of pancreatic cancer cells through the up-regulation of BDH2

LncRNA TP73 antisense RNA 1T (TP73-AS1) plays an important role in human malignancies. However, the levels of TP73-AS1 and its functional mechanisms in pancreatic cancer metastasis remain unknown, and the clinical significance of TP73-AS1 in human pancreatic cancer is also unclear. In the present study, the levels of TP73-AS1 and its candidate target miR-141 in pancreatic cancer and adjacent normal tissue were detected using qRT-PCR. The association between TP73-AS1 levels and the clinicopathologic characteristics of pancreatic cancer patients were analyzed. The relationship between TP73-AS1 and miR-141, and miR-141 and its candidate target 3-hydroxybutyrate dehydrogenase type 2 (BDH2) was confirmed using dual-luciferase reporter assays. TP73-AS1 and/or miR-141 were knocked down using siRNA or an inhibitor in pancreatic cancer cells and cell migration and invasion then examined. The results showed that TP73-AS1 was up-regulated in pancreatic cancer tissue and cell lines. High levels of TP73-AS1 were correlated with poor clinicopathological characteristics and shorter overall survival. MiR-141 was a direct target for TP73-AS1, while BDH2 was a direct target for miR-141. The knockdown of TP73-AS1 significantly inhibited the migration and invasion of pancreatic cancer cells, while the miR-141 inhibitor significantly restored the migration and invasion. Therefore, TP73-AS1 positively regulated BDH2 expression by sponging miR-141. These findings suggest that TP73-AS1 serves as an oncogene and promotes the metastasis of pancreatic cancer. Moreover, TP73-AS1 could serve as a predictor and a potential drug biotarget for pancreatic cancer.

Involvement of the long noncoding RNA NEAT1 in carcinogenesis

Altered expression levels of the long noncoding RNA (lncRNA) nuclear‐enriched abundant transcript 1 (NEAT1) have been reported in different types of cancer. More than half of the NEAT1 studies in cancer have been published within the last 2 years. In this review, we discuss very recent developments and insights into NEAT1 contribution to carcinogenesis. Summarizing the literature, it becomes obvious that NEAT1 is a lncRNA highly de‐/upregulated in a variety of cancer entities, in which it primarily acts as a competing endogenous RNA (ceRNA) which sponges tumor‐suppressive microRNA (miRNA). The sponged miRNA lose their ability to degrade, silence, or hamper translation of their downstream—mostly oncogenic—target transcripts, ultimately promoting carcinogenesis. This role of NEAT1 function in tumorigenesis suggests it may be a prognostic biomarker as well as potential therapeutic target, pending the completion of further studies into the underlying mechanisms.