m6A-modified circFOXK2 targets GLUT1 to accelerate oral squamous cell carcinoma aerobic glycolysis.

N6-methyladenosine (m6A) is an abundant nucleotide modification in mRNA, and its emerging roles have been gradually identified. However, the potential function of m6A and m6A-modified circular RNA (circRNA) is still unclear. Here, m6A-circRNA epitranscriptomic microarray analysis revealed a high-expressed m6A-modified circFOXK2 (hsa_circ_0000816, from FOXK2 gene) in oral squamous cell carcinoma (OSCC). For the biofunctions of OSCC, results revealed that circFOXK2 promoted the malignant phenotypes of OSCC cells. Methylated RNA immunoprecipitation sequencing (MeRIP-Seq) demonstrated that a remarkable m6A modified site was installed on glucose transporter 1 (GLUT1) mRNA. Mechanistically, circFOXK2 promoted the GLUT1 mRNA stability through cooperating with insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3) in a m6A-dependent manner. In summary, the present study explored the oncogenic role of m6A-modified circFOXK2 in OSCC through the m6A-dependent IGF2BP3/GLUT1 axis, indicating a potential therapeutic target for OSCC.

High-throughput microarray reveals the epitranscriptome-wide landscape of m6A-modified circRNA in oral squamous cell carcinoma.

BACKGROUND: Emerging transcriptome-wide high-throughput screenings reveal the landscape and functions of RNAs, such as circular RNAs (circRNAs), in human cancer. In addition, the post-transcriptional RNA internal modifications, especially N6-methyladenosine (m6A), greatly enrich the variety of RNAs metabolism. However, the m6A modification on circRNAs has yet to be addressed. RESULTS: Here, we report an epitranscriptome-wide mapping of m6A-modified circRNAs (m6A-circRNA) in oral squamous cell carcinoma (OSCC). Utilizing the data of m6A methylated RNA immunoprecipitation sequencing (MeRIP-seq) and m6A-circRNAs microarray, we found that m6A-circRNAs exhibited particular modification styles in OSCC, which was independent of m6A-mRNA. Besides, m6A modification on circRNAs frequently occurred on the long exons in the front part of the coding sequence (CDS), which was distinct from m6A-mRNA that in 3'-UTR or stop codon. CONCLUSION: In conclusion, our work preliminarily demonstrates the traits of m6A-circRNAs, which may bring enlighten for the roles of m6A-circRNAs in OSCC.

Isoliquiritigenin inhibits non-small cell lung cancer progression via m6A/IGF2BP3-dependent TWIST1 mRNA stabilization.

BACKGROUND: N6-methyladenosine (m6A) has been identified to regulate the tumorigenesis and development of various tumors, including non-small cell lung cancer (NSCLC). Isoliquiritigenin (ISL), derived from the Chinese herb licorice, shows a significant anti-tumor activity on multiple human cancers. However, the role of ISL on NSCLC through m6A is still unclear. PURPOSE: Here, we investigated the anti-tumor effect of ISL on NSCLC, and explored whether ISL affected the NSCLC phenotype by modulating its m6A modification. METHODS: Cell proliferation, migration and invasion assays were performed to evaluate the inhibitory effects of ISL on NSCLC cells. M6A enrichment was determined by m6A quantitative analysis. The mechanism regarding IGF2BP3 was explored using RIP-PCR, MeRIP-qPCR and RNA decay analysis. RESULTS: ISL significantly repressed the proliferation, migration and invasion of NSCLC cells in vitro. In addition, m6A reader IGF2BP3 expression significantly increased in NSCLC tissues compared to adjacent tissues, and was positively correlated with NSCLC patients' poor survival. Mechanistically, ISL reduced m6A modification and down-regulated IGF2BP3 expression in NSCLC. Furthermore, IGF2BP3 enhanced the mRNA stability of twist family bHLH transcription factor 1 (TWIST1) in m6A-dependent manner. Moreover, ISL treatment combined with TWSIT1 knockdown effectively reversed IGF2BP3 overexpression-induced NSCLC cells' proliferation, migration and invasion. CONCLUSION: Our findings uncover that ISL might function as an anticarcinogen through targeting IGF2BP3/m6A/TWIST1 axis for NSCLC.

Serum VEGF: Diagnostic Value of Acute Coronary Syndrome from Stable Angina Pectoris and Prognostic Value of Coronary Artery Disease.

BACKGROUND: Although the level of serum vascular endothelial growth factor (VEGF) is elevated in coronary artery disease (CAD) patients, its potential role in acute coronary syndrome (ACS) or stable angina pectoris (SAP) patients remains unclear. OBJECTIVES: To evaluate diagnostic accuracy of serum VEGF in determining ACS patients from SAP and analyze the association of serum VEGF with coronary artery lesions in SAP or the GRACE score in ACS, which is involved in the poor prognosis of low serum VEGF. METHODS: 248 CAD patients and 48 healthy subjects were enrolled in this study. Serum VEGF levels were detected by using ELISA. The Gensini score or GRACE score was calculated among SAP or ACS patients. All the patients were followed up for a period of 12 months (mean: 10.77 months). RESULTS: VEGF serum concentrations were higher in the ACS subgroup than in the SAP subgroup (P < 0.001) with diagnostic accuracy of ACS from SAP (AUC: 0.667, sensitivity: 68.5%, specificity: 60.1%, P < 0.001). Patients with high risk of Gensini score showed reduced VEGF levels (P < 0.001) accompanied by a negative correlation (r = -0.396, P < 0.001). Patients with a higher GRACE score indicated lower VEGF levels (P < 0.001). Low serum VEGF was one of the potential risk factors with adjusted HR of 0.531 (P=0.048). CONCLUSION: Serum VEGF exhibits efficient diagnostic value for detection of ACS from SAP with a cutoff value of 648.75 pg/mL. Low serum VEGF indicates severe coronary artery lesions and a higher GRACE score, which suggests poor clinical outcomes.

METTL3 Facilitates Oral Squamous Cell Carcinoma Tumorigenesis by Enhancing c-Myc Stability via YTHDF1-Mediated m6A Modification.

N6-Methyladenosine (m6A) is the most common internal modification of eukaryotic messenger RNA (mRNA) that occurred on the N6 nitrogen of adenosine. However, the roles of m6A in oral squamous cell carcinoma (OSCC) are still elusive. Here, we investigate the function and mechanism of methyltransferase-like 3 (METTL3) in OSCC tumorigenesis. Clinically, METTL3 was significantly upregulated in tissue samples and correlated with the poor prognosis of OSCC patients. Functionally, loss and gain studies illustrated that METTL3 promoted the proliferation, invasion, and migration of OSCC cells in vitro, and METTL3 knockdown inhibited tumor growth in vivo. Mechanistically, methylated RNA immunoprecipitation sequencing (MeRIP-seq) illustrated that METTL3 targeted the 3' UTR (near to stop codon) of the c-Myc transcript to install the m6A modification, thereby enhancing its stability. Furthermore, results revealed that YTH N6-methyladenosine RNA binding protein 1 (YTH domain family, member 1 [YTHDF1]) mediated the m6A-increased stability of c-Myc mRNA catalyzed by METTL3. In conclusion, our findings herein identify that METTL3 accelerates the c-Myc stability via YTHDF1-mediated m6A modification, thereby giving rise to OSCC tumorigenesis.

Perindopril Improves Cardiac Function by Enhancing the Expression of SIRT3 and PGC-1α in a Rat Model of Isoproterenol-Induced Cardiomyopathy.

Mitochondrial biosynthesis regulated by the PGC-1α-NRF1-TFAM pathway is considered a novel potential therapeutic target to treat heart failure (HF). Perindopril (PER) is an angiotensin-converting enzyme inhibitor that has proven efficacy in the prevention of HF; however, its mechanism is not well established. In this study, to investigate the mechanisms of PER in cardiac protection, a rat model of cardiomyopathy was established by continuous isoproterenol (ISO) stimulation. Changes in the body weight, heart weight index, echocardiography, histological staining, mitochondrial microstructure, and biochemical indicators were examined. Our results demonstrate that PER reduced myocardial remodeling, inhibited deterioration of cardiac function, and delayed HF onset in rats with ISO-induced cardiomyopathy. PER markedly reduced reactive oxygen species (ROS) production, increased the levels of antioxidant enzymes, inhibited mitochondrial structural destruction and increases the number of mitochondria, improved the function of the mitochondrial respiratory chain, and promoted ATP production in myocardial tissues. In addition, PER inhibited cytochrome C release in mitochondria and caspase-3 activation in the cytosol, thereby reducing the apoptosis of myocardial cells. Notably, PER remarkably up-regulated the mRNA and protein expression levels of Sirtuin 3 (SIRT3), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), nuclear respiratory factor 1 (NRF1), and mitochondrial transcription factor A (TFAM) in myocardial cells. Collectively, our results suggest that PER induces mitochondrial biosynthesis-mediated enhancement of SIRT3 and PGC-1α expression, thereby improving the cardiac function in rats with ISO-induced cardiomyopathy.

Correction to: Splicing factor derived circular RNA circUHRF1 accelerates oral squamous cell carcinoma tumorigenesis via feedback loop.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Splicing factor derived circular RNA circUHRF1 accelerates oral squamous cell carcinoma tumorigenesis via feedback loop.

Emerging evidences have suggested the vital roles of circular RNA (circRNA) in the human cancers. However, the underlying biological functions and biogenesis of circRNA in the oral squamous cell carcinoma (OSCC) is still ambiguous. Here, we investigate the oncogenic roles and biogenesis of the novel identified circRNA, circUHRF1 (hsa_circ_0002185), in the OSCC tumorigenesis. Results showed that circUHRF1 was markedly upregulated in the OSCC cells and tissue, besides, the overexpression was closely correlated with the poor prognosis of OSCC patients. Functionally, circUHRF1 promoted the proliferation, migration, invasion, and epithelial mesenchymal transformation (EMT) in vitro and the tumor growth in vivo. Mechanically, circUHRF1 acted as the sponge of miR-526b-5p, thereby positively regulating c-Myc. Transcription factor c-Myc could accelerate the transcription of TGF-ß1 and ESRP1. Moreover, splicing factor ESRP1 promoted the circularization and biogenesis of circUHRF1 by targeting the flanking introns, forming the circUHRF1/miR-526b-5p/c-Myc/TGF-ß1/ESRP1 feedback loop. In conclusion, our research identified the oncogenic roles of circUHRF1 in the OSCC tumorigenesis and EMT via circUHRF1/miR-526b-5p/c-Myc/TGF-ß1/ESRP1 feedback loop, shedding light on the pathogenic mechanism of circUHRF1 for OSCC and providing the potential therapeutic target.

Relationship between circulating concentration of Ang II, ADM and ADT and left ventricular hypertrophy in hypertension.

BACKGROUND: Left ventricular hypertrophy (LVH) is the most common structural damage in hypertensive complication and is an independent risk factor for assessing cardiovascular events. The aim of this study was explore the relationship between plasma concentration of angiotensin II (Ang II), Adrenomedulin (ADM) and adrenotensin (ADT) in patients with hypertension and LVH. METHODS: We enrolled 310 hypertensive patients from the department of cardiology of Tianjin Union Medical Center as the hypertension group and 39 healthy subjects as control group. Further grouping according to the LVMI (male LVMI≥115 g/m2, female LVMI≥95 g/m2) values for determining LVH in the 2013 ESC Hypertension Management Guidelines. Plasma levels of Ang II, ADM and ADT were measured using ELISA assay. RESULTS: The levels of plasma Ang II and ADM in essential hypertension (EH) were significantly higher than control group, and the essential hypertension combined left ventricular hypertrophy (EHCLVH) group was higher than essential hypertension not with left ventricular hypertrophy (EHNLVH) group (P<0.05). Correlation analyze showed that left ventricular mass index (LVMI) was positively related to Ang II and ADM, and negatively related to ADT. Logistic regression analyze indicated that LVH are strongly linked with systolic blood pressure (SBP), Ang II, ADM and ADT. ROC curve showed ADM and ADT have similar value in distinguish LVH. CONCLUSION: Plasma levels of Ang II, ADM and ADT might act as indicator to identify hypertensive LVH.

Circulating microRNA-92a level predicts acute coronary syndrome in diabetic patients with coronary heart disease.

PURPOSE: This study was designed to explore the value of monitoring miR-92a in T2DM patients with coronary heart disease (CHD). MATERIALS AND METHODS: 40 ACS patients with prior history of CHD and diabetes while the onset time of diabetes preceded that of CHD by more than 2 years were enrolled as the DACS group(diabetic ACS group). 40 ACS subjects who had had a definite diagnosis of CHD for more than 2 years with no history of T2DM were recuited as the CACS group(chronic CHD with ACS group). All enrolled subjects from DACS and CACS group came from an emergency basis and diagnosed with ACS by coronary angiography. Another 68 age- and sex-matched volunteers with chronic stable CHD without diabetes history were assigned as the control group (CHD group). We examined the serum levels of miR-92a and analyzed their correlations with blood pressure, glucose level, and lipid level. RESULTS: The levels of miR-92a were significantly elevated in the DACS group compared with those of the CACS and CHD groups. Multivariate analysis showed that miR-92a, systolic blood pressure (SBP), and glycosylated hemoglobin (HbA1c) were significantly related to ACS events in patients with T2DM. Forward stepwise binary logistic regression analysis identified miR-92a as an independent predictive factor for ACS events in the patients with T2DM. CONCLUSION: An elevated circulating miR-92a level was associated with an increased risk of ACS in CHD patients with T2DM. Thus the level of miR-92a, especially combined with elevated SBP and HbA1c, may be helpful in the detection of ACS in patients with T2DM.

Tongmai Yangxin pills anti-oxidative stress alleviates cisplatin-induced cardiotoxicity: Network pharmacology analysis and experimental evidence.

BACKGROUND: Tongmai Yangxin Pills (TMYXP), a traditional Chinese patent medicine, has been widely used to treat coronary heart disease for few decades. However, the potential protective effect of TMYXP on cisplatin-induced cardiotoxicity has not been reported. METHODS: The target proteins corresponding to compounds from Pharmmapper database, PubMed database and ChEMBL database were collected and construct a 'TMYXP-compound-target' network. DAVID database was used for annotation and enrichment pathways and String 9.1 database was used for analysis the protein-protein interaction. Cisplatin-induced rat cardiotoxicity model was established to verify the protective effects mechanism of TMYXP. RESULTS: The target proteins corresponding to compounds from multiple databases were collected and construct a TCM-compound-target network to enriched pathways with high enrichment score. GO analysis and enrichment clusters point that response of oxidative stress is the main biological process of TMYXP, and Nrf2 signaling pathway and MAPK signaling pathway might be the key functional pathways. In vivo experiments, we proved that TMYXP improves anti-oxidative stress ability and reduce apoptosis through regulating Nrf2/HO-1 pathway and p38-MAPK pathway. CONCLUSION: The effects of TMYXP on regulate cardiomyocyte free radical balance and reduce apoptosis, making it possible as a drug candidate for platinum chemotherapeutic induced cardiac injury.

Additional Diagnostic Value of Growth Differentiation Factor-15 (GDF-15) to N-Terminal B-Type Natriuretic Peptide (NT-proBNP) in Patients with Different Stages of Heart Failure.

BACKGROUND Growth differentiation factor-15 (GDF-15) is a promising biomarker of cardiac remodeling. The purpose of this study was to explore the diagnostic value of plasma GDF-15 levels in different stages of heart failure (HF) and to assess the relationship with ventricular remodeling. MATERIAL AND METHODS We enrolled 219 HF patients from the Department of Cardiology in Tianjin Union Medical Center as the HF group and 32 healthy subjects as the control group. Circulating GDF-15, NT-proBNP, procollagen I C-terminal propeptide (PICP), and N-terminal procollagen III propeptide (PIIINP) levels were measured using ELISA. Associations between GDF-15 and clinical indicators in cardiac remodeling were assessed using receiver operating characteristic (ROC) curves and Spearman correlation. All the patients were followed up for 1 year. RESULTS The level of plasma GDF-15 in HF patients was higher than in the control group (P<0.05) and increased with higher ACCF/AHA and NYHA classification (P<0.05). Patients with HFrEF had higher GDF-15 levels compared to patients with HFmrEF (P<0.05). GDF-15 and left ventricular mass index (LVMI) were significantly increased as early as the pre-clinical HF stage. Also, GDF-15 levels were positively correlated to LVMI (r=0.433, P<0.05), PICP (r=0.378, P<0.001) and PIIINP (r=0.382, P<0.001). ROC curves were constructed and GDF-15 plus NT-proBNP (AUC=0.905, 95%CI: 0.868-0.942, P<0.001) was superior to NT-proBNP (AUC=0.869, 95%CI: 0.825-0.913, P<0.001) in identifying HF. GDF-15 levels did not predict prognosis after a 1-year follow-up period. CONCLUSIONS GDF-15 combined with NT-proBNP significantly improves the accuracy of diagnosing HF. Plasma GDF-15 levels can indirectly reflect the degree of cardiac remodeling and fibrosis.

Differential and Predictive Value of Galectin-3 and Soluble Suppression of Tumorigenicity-2 (sST2) in Heart Failure with Preserved Ejection Fraction.

BACKGROUND Galectin-3 and soluble suppression of tumorigenicity-2 (sST2) are promising biomarkers of cardiac fibrosis and ventricular remodeling. The purpose of this study was to investigate the diagnostic and predictive value of galectin-3 and sST2 for use in patients who have heart failure with preserved ejection fraction (HFpEF). MATERIAL AND METHODS A total of 217 hospitalized patients with HF and 30 controls from a physical examination center were included. Venous blood was collected for the detection of circulating expression of galectin-3 and sST2. All the included patients were followed up regularly for 1 year (12±1 months). RESULTS The concentrations of galectin-3 and NT-proBNP were substantially higher following decreased ejection fraction (both P=0.000), except for sST2 (P=0.068 vs. control). In ROC analyses, galectin-3 and NT-proBNP distinguished HFpEF from controls with an area under the curve (AUC) of 0.819 (95% CI: 0.75-0.89, P=0.000) and 0.806 (95% CI: 0.66-0.82, P=0.000). In contrast, sST2 obtained a lower AUC of 0.584 (95% CI: 0.49-0.68, P=0.17) compared to galectni-3 and NT-proBNP. After adjustment for clinical factors and NT-proBNP, galectin-3 was strongly correlated with an increased risk of the endpoint events in HFpEF patients, and the hazard ratio per 1 SD increase of the galectin-3 level was 2.33 (95%CI: 1.72-2.94, P=0.009). CONCLUSIONS Galectin-3 is superior to sST2 in distinguishing HFpEF from controls and HFrEF.