lncRNA TTN‑AS1 upregulates RUNX1 to enhance glioma progression via sponging miR‑27b‑3p

RUNX transcription factors: biological functions and implications in cancer

Runt-related transcription factors (RUNX) are a family of transcription factors that are essential for normal and malignant hematopoietic processes. Their most widely recognized role in malignancy is to promote the occurrence and development of acute myeloid leukemia. However, it is worth noting that during the last decade, studies of RUNX proteins in solid tumors have made considerable progress, suggesting that these proteins are directly involved in different stages of tumor development, including tumor initiation, progression, and invasion. RUNX proteins also play a role in tumor angiogenesis, the maintenance of tumor cell stemness, and resistance to antitumor drugs. These findings have led to the consideration of RUNX as a tumor biomarker. All RUNX proteins are involved in the occurrence and development of solid tumors, but the role of each RUNX protein in different tumors and the major signaling pathways involved are complicated by tumor heterogeneity and the interacting tumor microenvironment. Understanding how the dysregulation of RUNX in tumors affects normal biological processes is important to elucidate the molecular mechanisms by which RUNX affects malignant tumors.

Prognostic significance of long noncoding RNA TTN-AS1 in various malignancies

BACKGROUND

Increasing evidence has demonstrated that high TTN-AS1 expression is highly related to poor prognosis in diverse human cancers. However, the findings concerning the prognostic value of TTN-AS1 were inconsistent, as these conclusions were usually drawn with relatively small sample sizes. Hence, this meta-analysis proposes to investigate the prognostic significance of TTN-AS1 in multiple malignancies systematically.

METHODS

Web of Science, Springer, Embase, PubMed, Cochrane Library, and Scopus databases were comprehensively searched to retrieve studies related to the TTN-AS1 expression with the prognosis of malignancies. The significance of the TTN-AS1 in cancers was estimated by hazard ratios (HRs) or odds ratios (ORs). Additionally, the Gene Expression Profiling Interactive Analysis (GEPIA) analysis tool was used to strengthen our results further.

RESULTS

Twenty studies involving 17 different cancers and 1330 patients were recruited into this meta-analysis. The research revealed that high TTN-AS1 expression was remarkably associated with unfavorable overall survival (OS) (HR = 2.07, 95%CI [1.78, 2.41], p < .00001) when compared with low TTN-AS1 expression in malignancies. Additionally, elevated TTN-AS1 expression significantly contributed to lymph node metastasis (OR = 4.09, 95%CI [3.08, 5.44], p < .0001), larger tumor size (OR = 2.42, 95%CI [1.56, 3.77], p < .0001), worse tumor differentiation (OR = 0.36, 95%CI [0.22, 0.59], p < .0001) and more advanced tumor stage (OR = 0.29, 95%CI [0.22, 0.38], p < .0001) with low or no heterogeneity existing. Moreover, high TTN-AS1 expression  was connected with worse disease-free survival in five different cancers based on the GEPIA online database.

CONCLUSIONS

The results of this meta-analysis support that high TTN-AS1 expression significantly correlates with worse prognosis in various cancers. Therefore, TTN-AS1 may be considered as a novel biomarker for malignancies.

Oestrogen treatment restores dentate gyrus development in premature newborns by IGF1 regulation

Prematurely-born infants cared for in the neonatal units suffer from memory and learning deficits. Prematurity diminishes neurogenesis and synaptogenesis in the hippocampal dentate gyrus (DG). This dysmaturation of neurons is attributed to elevated PSD95, NMDR2A, and IGF1 levels. Since oestrogen treatment plays key roles in the development and plasticity of DG, we hypothesized that 17β-estradiol (E2) treatment would ameliorate neurogenesis and synaptogenesis in the DG, reversing cognitive deficits in premature newborns. Additionally, E2-induced recovery would be mediated by IGF1 signalling. These hypotheses were tested in a rabbit model of prematurity and nonmaternal care, in which premature kits were gavage-fed and reared by laboratory personnel. We compared E2- and vehicle-treated preterm kits for morphological, molecular, and behavioural parameters. We also treated kits with oestrogen degrader, RAD1901, and assessed IGF1 signalling. We found that E2 treatment increased the number of Tbr2+ and DCX+ neuronal progenitors and increased the density of glutamatergic synapses in the DG. E2 treatment restored PSD95 and NMDAR2A levels and cognitive function in preterm kits. Transcriptomic analyses showed that E2 treatment contributed to recovery by influencing interactions between IGF1R and neurodegenerative, as well as glutamatergic genes. ERα expression was reduced on completion of E2 treatment at D7, followed by D30 elevation. E2-induced fluctuation in ERα levels was associated with a reciprocal elevation in IGF1/2 expression at D7 and reduction at D30. ERα degradation by RAD1901 treatment enhanced IGF1 levels, suggesting ERα inhibits IGF1 expression. E2 treatment alleviates the prematurity-induced maldevelopment of DG and cognitive dysfunctions by regulating ERα and IGF1 levels.

LncRNA DNAJC3-AS1 promotes the biological functions of papillary thyroid carcinoma via regulating the microRNA-27a-3p/CCBE1 axis

Long noncoding RNA DNAJC3-AS1 (lncRNA DNAJC3-AS1) has been probed in many studies, while the regulatory mechanism of DNAJC3-AS1 on papillary thyroid carcinoma (PTC) via regulating microRNA (miR)-27a-3p remains inadequate. This research aims to depict the role of DNAJC3-AS1, miR-27a-3p, collagen, and calcium-binding EGF domain-containing protein 1 (CCBE1) on PTC development. DNAJC3-AS1, miR-27a-3p, and CCBE1 expression levels in PTC tissues and adjacent normal tissues were tested. The relation of DNAJC3-AS1, miR-27a-3p, and CCBE1 was analyzed. DNAJC3-AS1 and miR-27a-3p and CCBE1-related oligonucleotides were transfected into IHH-4 cells to investigate their role in PTC development. Cell tumorigenicity was detected by in vivo assay. DNAJC3-AS1 and CCBE1 expressed highly and miR-27a-3p expressed lowly in PTC. Downregulation of DNAJC3-AS1, upregulating miR-27a-3p or downregulating CCBE1 impaired the malignant behaviors of IHH-4 cells. Depletion of miR-27a-3p reversed the DNAJC3-AS1 suppression-induced phenotypic inhibition of IHH-4 cells. DNAJC3-AS1 bound to miR-27a-3p and CCBE1 as a target of miR-27a-3p. Our study highlights that DNAJC3-AS1 inhibits miR-27a-3p to promote CCBE1 expression, thereby facilitating PTC development. This study affords distinguished therapeutic strategies and novel research directions for PTC treatment.

Antisense lncRNA CHROMR is linked to glioma patient survival

Background: Natural non-coding antisense transcripts (ncNATs) are long non-coding RNAs (lncRNA) transcribed from the opposite strand of a separate protein coding or non-coding gene. As such, ncNATs can increase overlapping mRNA (and the coded protein) levels by stabilizing mRNA, absorbing inhibitory miRNAs and protecting the mRNA from degradation, or conversely decrease mRNA (or protein) levels by directing the mRNA towards degradation or inhibiting protein translation. Recently, growing numbers of ncNATs were shown to be dysregulated in cancerous cells, however, actual impact of ncNATs on cancer progression remains largely unknown. We therefore investigated gene expression levels of natural antisense lncRNA CHROMR (Cholesterol Induced Regulator of Metabolism RNA) and its sense protein coding gene PRKRA (Protein Activator of Interferon Induced Protein Kinase EIF2AK2) in gliomas. Next, we checked CHROMR effect on the survival of glioma patients. Methods: We performed RNA-seq on post-surgical tumor samples from 26 glioma patients, and normal brain tissue. Gene expression in TPM values were extracted for CHROMR and PRKRA genes. These data were validated using the TCGA and GTEx gene expression databases. Results: The gene expression level of ncNAT lncRNA CHROMR in glioma tissue was significantly higher compared to healthy brain tissue, while the expression of its sense counterpart protein coding PRKRA mRNA did not differ between glioma and healthy samples. Survival analysis showed lower survival rates in patients with low mRNA PRKRA/lncRNA CHROMR gene expression ratio compared to high ratio showing a link between lncRNA CHROMR and glioma patient survival prognosis. Conclusion: Here we show that elevated levels of lncRNA CHROMR (i.e., low ratio of mRNA PRKRA/lncRNA CHROMR) is associated with poor prognosis for glioma patients.

A Novel Thrombosis-Related Signature for Predicting Survival and Drug Compounds in Glioblastoma

Glioblastoma is the most common primary tumor in the central nervous system, and thrombosis-associated genes are related to its occurrence and progression. Univariate Cox and LASSO regression analysis were utilized to develop a new prognostic signature based on thrombosis-associated genes. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and HALLMARK were used for functional annotation of risk signature. ESTIMATE, MCP-counter, xCell, and TIMER algorithms were used to quantify immune infiltration in the tumor microenvironment. Genomics of Drug Sensitivity in Cancer (GDSC) was used for selecting potential drug compounds. Risk signature based on thrombosis-associated genes shows moderate performance in prognosis prediction. The functional annotation of the risk signature indicates that the signaling pathways related to the cell cycle, apoptosis, tumorigenesis, and immune suppression are rich in the high-risk group. Somatic mutation analysis shows that tumor-suppressive gene TP53 and oncogene PTEN have higher expression in low-risk and high-risk groups, respectively. Potential drug compounds are explored in risk score groups and show higher AUC values in the low-risk score group. A nomogram with valuable prognostic factors exhibits high sensitivity in predicting the survival outcome of GBM patients. Our research screens out multiple thromboses-associated genes with remarkable clinical significance in GBM and further develops a meaningful prognostic risk signature predicting drug sensitivity and survival outcome.

Protective Role of lncRNA TTN-AS1 in Sepsis-Induced Myocardial Injury Via miR-29a/E2F2 Axis

OBJECTIVE

Approximately 50% of patients with sepsis encounter myocardial injury. The mortality of septic patients with cardiac dysfunction (approx. 70%) is much higher than that of patients with sepsis only (20%). A large number of studies have suggested that lncRNA TTN-AS1 promotes cell proliferation in a variety of diseases. This study delves into the function and mechanism of TTN-AS1 in sepsis-induced myocardial injury in vitro and in vivo.

METHODS

LPS was used to induce sepsis in rats and H9c2 cells. Cardiac function of rats was assessed by an ultrasound system. Myocardial injury was revealed by hematoxylin-eosin (H&E) staining. Gain and loss of function of TTN-AS1, miR-29a, and E2F2 was achieved in H9c2 cells before LPS treatment. The expression levels of inflammatory cytokines and cTnT were monitored by ELISA. The expression levels of cardiac enzymes as well as reactive oxygen species (ROS) activity and mitochondrial membrane potential (MMP) were measured using the colorimetric method. The expression levels of TTN-AS1, miR-29a, E2F2, and apoptosis-related proteins were measured by RT-qPCR and/or western blotting. The proliferation and apoptosis of H9c2 cells were separately detected by CCK-8 and flow cytometry. Luciferase reporter assay was used to verify the targeting relationships among TTN-AS1, miR-29a and E2F2, and RIP assay was further used to confirm the binding between miR-29a and E2F2.

RESULTS

TTN-AS1 was lowly expressed, while miR-29a was overexpressed in the cell and animal models of sepsis. Overexpression of TTN-AS1 or silencing of miR-29a reduced the expression levels of CK, CK-MB, LDH, TNF-B, IL-1B, and IL-6 in the supernatant of LPS-induced H9c2 cells, attenuated mitochondrial ROS activity, and enhanced MMP. Consistent results were observed in septic rats injected with OE-TTN-AS1. Knockdown of TTN-AS1 or overexpression of miR-29a increased LPS-induced inflammation and injury in H9c2 cells. TTN-AS1 regulated the expression of E2F2 by targeting miR-29a. Overexpression of miR-29a or inhibition of E2F2 abrogated the suppressive effect of TTN-AS1 overexpression on myocardial injury.

CONCLUSION

This study indicates TTN-AS1 attenuates sepsis-induced myocardial injury by regulating the miR-29a/E2F2 axis and sheds light on lncRNA-based treatment of sepsis-induced cardiomyopathy.

The Promotive Effect of the Active Ingredients of Atractylodes macrocephala on Intestinal Epithelial Repair Through Activating Ca2+ Pathway

Atractylodes macrocephala ( AM) is a famous traditional Chinese medicine for intestinal epithelial restitution through activating Ca2+ channels. However, the roles of specific AM compositions in intestinal epithelial restitution are sparse. Therefore, this study aimed to compare the concrete effects of the 4 active ingredients (atractylon, β-eudesmol, atractylenolide II, atractylenolide III) of AM and their combination on intestinal epithelial repair and the Ca2+ pathway in intestinal epithelial cell (IEC-6) cells. First, the best combination of the 4 ingredients with an optimal mixing ratio of atractylon: β-eudesmol: atractylenolide II: atractylenolide III = 1:2:2:2 was demonstrated by a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide orthogonal experiment. Subsequently, enzyme-linked immunosorbent assay was used to measure anti-inflammatory cytokine levels, the migratory ability was evaluated by cell scratch experiments, cell cycle analysis and [Ca2+]cyt concentration in cells were detected by flow cytometry, and the expression of the Ca2+ pathway-related genes was detected by immunofluorescence staining, quantitative polymerase chain reaction and whole blood assays. Our result showed that atractylon, β-Eudesmol, atractylenolide II, and atractylenolide III showed different abilities to promote the IEC-6 cells proliferation, migration, and the expression of anti-inflammatory cytokines interleukin (IL)-2, IL-10, and ornithine decarboxylase, as well as the intracellular [Ca2+]cyt concentration through stromal interaction molecule 1 transposition to activate Ca2+ pathway. Thereinto, atractylenolide III was the main active ingredient of AM for pro-proliferation and anti-inflammation, and the combination of 4 AM ingredients performed better beneficial effects on IEC-6 cells. Therefore, our study suggested that atractylenolide III was the active ingredient of AM for intestinal epithelial repair through activating the Ca2+ pathway, and the 4 ingredients of AM have a synergy in intestinal epithelial repair.

Targeting Long Non-Coding RNA TTN-AS1 Suppresses Bladder Cancer Progression

Background: To explore the biological and clinical effects of titin-antisense RNA1 (TTN-AS1) in bladder cancer (BC) and the association between TTN-AS1 and activating transcription factor 2 (ATF2) in BC. Methods: The Kaplan-Meier method was performed to analyze the association between the expression of TTN-AS1 and prognosis of BC patients from TCGA data set and our institution. Quantitative real-time PCR (RT-PCR) was conducted to explore the expression of TTN-AS1 between the patients who underwent TURBT and Re-TURBT. MTT, colony formation, and tumor formation assays were conducted to evaluate the effect of TTN-AS1 on the ability of proliferation in BC cell lines. Transwell assay was performed to evaluate the effect of TTN-AS1 on the ability of invasion in BC cell lines. Bioinfomatics and immunohistochemical staining was used to identify the relationship between TTN-AS1 and ATF2. Results: The higher expression of TTN-AS1 was related to poorer disease-free survival (DFS) in patients with BC. The expression of TTN-AS1 was higher in BC patients who underwent Re-TURBT compared with BC patients who underwent TURBT. Knocking down TTN-AS1 resulted in inhibiting the ability of proliferation and invasion of BC cells. ATF2 may serve as a downstream target of TTN-AS1 in BC, and the high expression of ATF2 is also related to adverse DFS. Conclusion: Our study reveals that TTN-AS1 serves as an oncogene by activating ATF2 in BC. The findings suggest that TTN-AS1 may act as a novel therapeutic target for patients with BC.

Long non-coding RNA TTN-AS1/microRNA-199a-3p/runt-related transcription factor 1 gene axis regulates the progression of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) has a high degree of malignancy, which affects the quality of life and prognosis of patients with OSCC. Our study aimed to reveal the function of long non-coding RNA TTN-AS1/microRNA-199a-3p (miR-199a-3p)/runt-related transcription factor 1 (RUNX1) axis in OSCC progression, thereby providing a novel OSCC effective strategy. Real-time quantitative polymerase chain reaction and western blotting were performed to detect the expression of TTN-AS1, miR-199a-3p, and RUNX1 in OSCC. Several cell functional experiments, including Cell Counting Kit-8, flow cytometry, and cell adhesion assays, were used to assess cell proliferation, apoptosis, adhesion, and migration. A luciferase assay was performed to confirm the interaction between TTN-AS1, miR-199a-3p, and RUNX1. Our results revealed that TTN-AS1 and RUNX1 were upregulated in OSCC tissues and cells, whereas miR-199a-3p expression was downregulated. Knockdown of TTN-AS1 or RUNX1 suppressed cell proliferation, adhesion, and migration but induced apoptosis. Additionally, miR-199a-3p inhibitor partly relieved the effects of silencing TTN-AS1 and RUNX1 in OSCC cells due to their targeting relationship. In conclusion, TTN-AS1 and RUNX1 could promote OSCC progression and miR-199a-3p partly relieved the effects of TTN-AS1 and RUNX1.

Regulation of RUNX proteins by long non-coding RNAs and circular RNAs in different cancers

RUNX proteins have been shown to behave as "double-edge sword" in wide variety of cancers. Discovery of non-coding RNAs has played linchpin role in improving our understanding about the post-transcriptional regulation of different cell signaling pathways. Several new mechanistic insights and distinct modes of cross-regulation of RUNX proteins and non-coding RNAs have been highlighted by recent research. In this review we have attempted to provide an intricate interplay between non-coding RNAs and RUNX proteins in different cancers. Better conceptual and mechanistic understanding of layered regulation of RUNX proteins by non-coding RNAs will be helpful in effective translation of the laboratory findings to clinically effective therapeutics.

TTN-AS1 as a potential diagnostic and prognostic biomarker for multiple cancers

The long noncoding RNAs (lncRNAs) are non-coding RNAs that are more than 200 nucleotides in length, and one of several types of non-coding RNAs (ncRNAs). The lncRNAs function in diverse biological processes in normal cells, such as cellular differentiation and cell cycle regulation. There is also evidence that some aberrantly regulated lncRNAs function as oncogenes or tumor suppressor genes in various cancers. For example, TTN-AS1 is a lncRNA that binds to titin mRNA (TTN) and has pro-oncogenic effects in many cancers. Overexpression of TTN-AS1 correlates with poor prognosis in breast cancer, lung cancer, digestive system neoplasms, reproductive system cancers, and other cancers. Furthermore, increased TTN-AS1 expression correlates with more advanced pathology and tumor malignancy. In this review, we comprehensively summarize recent studies on the molecular mechanisms of TTN-AS1 regulation and the role of TTN-AS1 in the carcinogenesis and progression of numerous tumors.

Long noncoding RNA LINC00520 accelerates lung adenocarcinoma progression via miR-1252-5p/FOXR2 pathway

It has been corroborated that long noncoding RNA (lncRNA) played fundamental function in various human malignancies development including lung adenocarcinoma (lung ADC). In our study, LINC00520 roles in lung ADC tumorigenesis were explored. We found that LINC00520 level was elevated in lung ADC tissues and cell lines. Besides, the LINC00520 expression had a negative connection with miR-1252-5p level in lung ADC tissues. Additionally, our results demonstrated the reciprocal repression influence between LINC00520 and miR-1252-5p. Moreover, luciferase reporter assays, RIP (RNA-binding protein immunoprecipitation) and pull down assays revealed that miR-1252-5p regulated LINC00520 in RISC-dependent. Furthermore, knockdown of LINC00520 inhibited lung ADC cells proliferation, migration and invasion, while co-transfection with a miR-1252-5p inhibitor inverted these influences. Additionally, the findings also demonstrated that FOXR2 was a target of miR-1252-5p; thus, LINC00520 could regulate FOXR2 level. Moreover, LINC00520 silencing suppressed the tumor growth of lung ADC in vivo. In summary, our data indicated that LINC00520 may act as a ceRNA to modulated FOXR2 level by sponging miR-1252-5p, which might bring a potential and effective biomarker to lung ADC treatment.

Adsorption of miR-218 by lncRNA HOTAIR regulates PDE7A and affects glioma cell proliferation, invasion, and apoptosis

OBJECTIVE

To evaluate the role of targeted adsorption of miR-218 by long-chain non-coding RNAHOTAIR to regulate PDE7A on glioma cell proliferation, invasion, and apoptosis.

METHODS

The expressions of lncRNA HOTAIR, miR-218, and PDE7A in glioma tissues and normal parcancer tissues, NHA and glioma cell lines were determined, and correlations among the three genes were analyzed. The subcellular localization of lncRNA HOTAIR was determined by fluorescent in situ hybridization. Dual-luciferase reporter assay was used to validate the targeted relationship between lncRNA HOTAIR/miR-218/PDE7A. Glioma cells were grouped to receive intervention of lncRNA HOTAIR or miR-218. MTT, transwell, and flow cytometry were performed to determine the proliferation, invasion, and apoptosis of cells.

RESULTS

Compared with the normal tissues and cells, the expression of lncRNA HOTAIR was increased while miR-218 was suppressed in glioma tissues samples and cells (all P<0.05). Inhibition of lncRNA HOTAIR expression, was able to induce apoptosis and suppress the proliferation and invasion of cells (all P<0.05). LncRNA HOTAIR is mainly localized in the cytoplasm, and is able to adsorb miR-218 as ceRNA. The effect of knockdown of HOTAIR on glioma cells could be partially rescued by miR-218 inhibitor. The expression of PDE7A was enhanced in glioma tissues and cells compared to normal tissues and cells (all P<0.05), which positively correlated with the expression of HOTAIR (r=0.546, P<0.05) and negatively correlated with the expression of miR-218 (r=0.363, P<0.05). The targeted relationship between miR-218 and PDE7A was validated: Overexpression of miR-218 was able to suppress the proliferation and invasion of glioma cells and restrain apoptosis compared to the miR-NC group (all P<0.05). The effect of miR-218 on glioma cells could be partially rescued by PDE7A.

CONCLUSION

lncRNA HOTAIR can adsorb miR-218 to regulate expression of PDE7A and promote the malignant biologic behavior of glioma cells.