Construction of an EMT-related lncRNA prognostic signature for lung adenocarcinoma and functional verification of its hub gene LINC01615.

BACKGROUND: The epithelial-mesenchymal transition (EMT) plays a vital role in the progression of lung adenocarcinoma (LUAD). Long non-coding RNAs (lncRNAs) participate in the EMT process as an important regulatory factor and have the potential to serve as prognostic biomarkers. We aimed to construct a novel lncRNA prognostic signature for LUAD based on EMT-related lncRNAs, identify EMT-related hub lncRNA, and investigate its biological functions. METHODS: RNA-seq data, clinical and survival information were obtained from The Cancer Genome Atlas database. The EMT-related lncRNA prognostic signature (EMTscore) was constructed using the Least Absolute Shrinkage and Selection Operator Cox regression analysis. The efficiency of EMTscore in predicting the prognosis of LUAD was evaluated through the area under the time-dependent receiver operating characteristic (ROC) curves. The hub lncRNA of the prognostic signature was selected using a co-expression network map, and its effects on cell proliferation and metastasis were explored by in vitro experiments. RESULTS: We constructed a prognostic signature (EMTscore) containing 8 tumor-high expressed lncRNAs. The EMTscore performed well in predicting overall survival rates with AUC values of 0.708 at 5 years in the training set. EMTscore could independently predict the survival of LUAD, with HR = 4.011 (95% CI 2.430-6.622) in the multivariate Cox regression. Importantly, we identified LINC01615 as the hub lncRNA in the EMTscore and revealed that LINC01615 enhanced the proliferation, migration, and EMT of lung cancer cells. CONCLUSIONS: A new EMT-related lncRNA prognostic signature named EMTscore was developed, and LINC01615 was identified as the hub lncRNA of EMTscore. The hub lncRNA LINC01615 had an oncogenic biological function in LUAD.

Prognostic value of interleukin-6 in atrial fibrillation: A cohort study and meta-analysis.

OBJECTIVE: The prognostic value of interleukin-6 (IL-6) in patients with atrial fibrillation (AF) has not been fully elucidated. Therefore, we conducted a cohort study and a meta-analysis to assess the predictive value of IL-6 for stroke and mortality in patients with AF. METHODS: A cohort study was performed in newly diagnosed non-valvular patients with AF. A total of 217 patients with AF were followed up for a mean of 27 months. A multivariate Cox regression analysis was used to evaluate the association between IL-6 and stroke/all-cause mortality. The incremental value was also assessed by adding IL-6 to the CHA2DS2-VASc score. Besides, a meta-analysis of all reported cohort studies and our cohort study was conducted to validate the association of circulating IL-6 and stroke/mortality in patients with AF. RESULTS: Our cohort study showed that elevated plasma level of IL-6 was an independent risk factor for predicting stroke [hazard ratio (HR)=3.81; 95% confidence interval (CI), 1.11-13.05; p=0.033] and all-cause mortality (HR=3.11; 95% CI, 1.25-7.72; p=0.015) in patients with AF. Adding IL-6 levels to CHA2DS2-VASc score showed limited improvement of the predictive power for stroke [area under curve (AUC) from 0.81 to 0.88, p=0.006]. Meta-analysis confirmed that increased circulating level of IL-6 was significantly associated with increased risk of stroke (pooled HR=1.97; 95% CI, 1.22-3.17; p=0.006) and all-cause mortality (pooled HR=2.73; 95% CI, 2.29-3.25; p<0.001). CONCLUSION: Increased circulating level of IL-6 was significantly associated with greater risk of stroke and all-cause mortality in patients with AF. Adding IL-6 biomarker to the CHA2DS2-VASc score may help to determine the management of AF treatment.

Inflammation characteristics and anti-inflammation treatment with tocilizumab of severe/critical COVID-19 patients: A retrospective cohort study.

The efficacy of tocilizumab on the prognosis of severe/critical COVID-19 patients is still controversial so far. We aimed to delineate the inflammation characteristics of severe/critical COVID-19 patients and determine the impact of tocilizumab on hospital mortality. Here, we performed a retrospective cohort study which enrolled 727 severe or critical inpatients (≥18 years old) with laboratory-confirmed COVID-19 from Huoshenshan Hospital (Wuhan, China), among which 50 patients received tocilizumab. This study confirmed that most recovered patients manifested relatively normal inflammation levels at admission, whereas most of the deceased cases presented visibly severe inflammation at admission and even progressed into extremely aggravated inflammation before their deaths, proved by some extremely high concentrations of interleukin-6, procalcitonin, C-reactive protein and neutrophil count. Moreover, based on the Cox proportional-hazards models before or after propensity score matching, we demonstrated that tocilizumab treatment could lessen mortality by gradually alleviating excessive inflammation and meanwhile continuously enhancing the levels of lymphocytes within 14 days for severe/critical COVID-19 patients, indicating potential effectiveness for treating COVID-19.

Single-nucleotide polymorphism rs4142441 and MYC co-modulated long non-coding RNA OSER1-AS1 suppresses non-small cell lung cancer by sequestering ELAVL1.

Single-nucleotide polymorphisms (SNP) and long non-coding RNAs (lncRNAs) have been involved in the process of lung cancer. Following clues given by lung cancer risk-associated SNP, we aimed to find novel functional lncRNAs as candidate targets in lung cancer. We identified a lncRNA Oxidative Stress Responsive Serine Rich 1 Antisense RNA 1 (OSER1-AS1) through a lung cancer risk-associated SNP rs4142441. OSER1-AS1 was down-regulated in tumor tissue and its low expression was significantly associated with poor overall survival among non-smokers in non-small cell lung cancer (NSCLC) patients. Gain- and loss-of-function studies showed that OSER1-AS1 acted as a tumor suppressor by inhibiting lung cancer cell growth, migration and invasion in vitro. Xenograft tumor assays and a metastasis mouse model confirmed that OSER1-AS1 suppressed tumor growth and metastasis in vivo. The promoter of OSER1-AS1 was repressed by MYC, and the 3'-end of OSER1-AS1 was competitively targeted by microRNA hsa-miR-17-5p and RNA-binding protein ELAVL1. Our results indicated that OSER1-AS1 exerted tumor-suppressive functions by acting as an ELAVL1 decoy to keep it away from its target mRNAs. Our findings characterized OSER1-AS1 as a new tumor-suppressive lncRNA in NSCLC, suggesting that OSER1-AS1 may be suitable as a potential biomarker for prognosis, and a potential target for treatment.

Circulating Long Noncoding RNAs Act as Diagnostic Biomarkers in Non-Small Cell Lung Cancer.

Identification of novel effective early diagnostic biomarkers may provide alternative strategies to reduce the mortality for non-small cell lung cancer (NSCLC) patients. Circulating long non-coding RNAs (lncRNAs) have emerged as a new class of promising cancer biomarkers. Our study aimed to identify circulating lncRNAs for diagnosing NSCLC. A total 528 plasma samples were continuously collected and allocated to four progressive phases: discovery, training, verification, and expansion phases. The expression of candidate lung cancer related lncRNAs were detected using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). We identified a 4-lncRNA panel (RMRP, NEAT1, TUG1, and MALAT1) that provided a high diagnostic value in NSCLC (AUC = 0.86 and 0.89 for training and verification phase, respectively). Subgroup analyses showed that the 4-lncRNA panel had a sensitivity of 78.95% [95% confidence interval (CI) = 62.22%-89.86%] in stage I-II patients and 75.00% (95% CI = 52.95%-89.40%) in patients with small tumor size (≤3cm). Notably, the sensitivity of 4-lncRNA panel was significantly higher than that of routine protein panels in adenocarcinoma (CEA, CA125, and CYFRA21-1, 86.30% vs. 73.96%). Adding 4-lncRNA to protein markers significantly improved the diagnostic capacity in both adenocarcinoma (AUC=0.85, 95% CI = 0.78-0.91) and squamous cell carcinoma (AUC=0.93, 95% CI = 0.86-0.97). In conclusion, we identified a plasma 4-lncRNA panel that has considerable clinical value in diagnosing NSCLC. The 4-lncRNA panel could improve the diagnostic values of routine tumor protein markers in diagnosing NSCLC. Circulating lncRNAs could be used as promising candidates for NSCLC diagnosis.

Abivertinib, a novel BTK inhibitor: Anti-Leukemia effects and synergistic efficacy with homoharringtonine in acute myeloid leukemia.

Ibrutinib, an inhibitor of Bruton tyrosine kinase (BTK), has shown promising pharmacologic effects in acute myeloid leukemia (AML). In this study, we report that abivertinib or AC0010, a novel BTK inhibitor, inhibits cell proliferation, reduces colony-forming capacity, and induces apoptosis and cell cycle arrest in AML cells, especially those harboring FLT3-ITD mutations. Abivertinib was also found to be more sensitive than ibrutinib in treating AML. We demonstrate that in addition to targeting the phosphorylation of BTK, abivertinib also targeted the crucial PI3K survival pathway. Furthermore, abivertinib suppressed the expression of p-FLT3 and the downstream target p-STAT5 in AML cells harboring FLT3-ITD mutations. Moreover, in vitro and in vivo data revealed synergistic activity between abivertinib and homoharringtonine (HHT), a natural plant alkaloid commonly used in China, in treating AML cells with or without FLT3-ITD mutations. Collectively, these preclinical data suggest that abivertinib may be a promising novel agent for AML, with potential for combination treatment with HHT. Clinical studies on abivertinib-involved therapy are planned.

Hypoxia-sensitive LINC01436 is regulated by E2F6 and acts as an oncogene by targeting miR-30a-3p in non-small cell lung cancer.

Dysregulation of long noncoding RNA (lncRNA) is known to be involved in numerous human diseases, including lung cancer. However, the precise biological functions of most lncRNA remain to be elucidated. Here, we identified a novel up-regulated lncRNA, LINC01436 (RefSeq: NR_110419.1), in non-small cell lung cancer (NSCLC). High expression of LINC01436 was significantly associated with poor overall survival. Notably, LINC01436 expression was transcriptionally repressed by E2F6 under normoxia, and the inhibitory effect was relieved in a hypoxic microenvironment. Gain- and loss-of-function studies revealed that LINC01436 acted as a proto-oncogene by promoting lung cancer cell growth, migration and invasion in vitro. Xenograft tumor assays in nude mice confirmed that LINC01436 promoted tumor growth and metastasis in vivo. Mechanistically, LINC01436 exerted biological functions by acting as a microRNA (miR)-30a-3p sponge to regulate the expression of its target gene EPAS1. Our findings characterize LINC01436 as a new hypoxia-sensitive lncRNA with oncogenic function in NSCLC, suggesting that LINC01436 may be a potential biomarker for prognosis and a potential target for treatment.

Plasma exosome levels in non-small-cell lung cancer: Correlation with clinicopathological features and prognostic implications.

BACKGROUND: Biomarker studies revealed important clinical significance of exosome for cancer patients. However, there is currently no consensus on exosome quantification methods. METHODS: Bicinchoninic acid (BCA) method, acetylcholinesterase (AChE) method and nanoparticle tracking analysis (NTA) were utilized to quantify 20 plasma exosome samples, and interrelations between these three methods were explored. Associations of plasma exosome levels with characteristics and prognosis of 208 non-small-cell lung cancer (NSCLC) patients were investigated. RESULTS: Results of the three methods for exosome quantification were significantly correlated with each other. Correlation coefficient between AChE and NTA (r= 0.79, P< 0.001) was greater than that between BCA and NTA (r= 0.64, P= 0.003). Plasma exosome levels of 208 NSCLC patients were then quantified with AChE method. Exosome level was significantly associated with tumour stage (P< 0.001) and the history of chronic obstructive pulmonary disease (P= 0.023). Cox proportional hazard analysis demonstrated that higher exosome level was independently associated with poorer overall survival (P= 0.033; hazard ratio = 1.72, 95% confidence interval: 1.05-2.83). CONCLUSIONS: Plasma exosome level correlates with tumor stage and the history of chronic obstructive pulmonary disease, and may serve as a prognostic factor for NSCLC.

Long non-coding RNA MUC5B-AS1 promotes metastasis through mutually regulating MUC5B expression in lung adenocarcinoma.

Long non-coding RNAs (lncRNAs) have been involved in the process of cancer occurrence, progression, and treatment. Lung cancer-related lncRNAs are still an emerging field, thus we sought to identify novel functional lncRNAs as candidate targets in lung cancer. Here, we identified one novel lncRNA, MUC5B-AS1 (Ensembl: ENST00000532061.2). MUC5B-AS1 was upregulated in lung adenocarcinoma tissues compared with normal lung tissues. Moreover, MUC5B-AS1 promoted lung cancer cell migration and invasion in vitro and promoted lung cancer cell metastasis in vivo. MUC5B-AS1 and its cognate sense transcript MUC5B were highly co-expressed and mutually regulated in lung adenocarcinoma. Mechanistically, MUC5B-AS1 promoted cell migration and invasion by forming an RNA-RNA duplex with MUC5B, thereby increasing MUC5B expression levels in lung adenocarcinoma. The high expression of MUC5B was significantly associated with poor outcomes in lung adenocarcinoma. Our findings highlight MUC5B-AS1 functions as an oncogenic lncRNA in tumor metastasis and implicate MUC5B-AS1 as an attractive candidate target for lung adenocarcinoma treatment.

Circulating exosomal microRNAs as prognostic biomarkers for non-small-cell lung cancer.

Exosomal miRNAs are proposed as excellent candidate biomarkers for clinical applications. However, little is known about their potential roles as prognostic biomarkers in lung cancer. In this study, we explored the prognostic value of plasma exosomal microRNAs (miRNAs) for non-small-cell lung cancer (NSCLC). Using a quantitative polymerase chain reaction (qPCR) array panel, we analyzed 84 plasma exosomal miRNAs in 10 lung adenocarcinoma patients and 10 matched healthy controls. The qPCR array showed 30 aberrantly expressed exosomal miRNAs. Nine candidate miRNAs were selected based on differential expression and previous reports for further evaluating their prognostic roles in 196 NSCLC patients. Elevated levels of exosomal miR-23b-3p, miR-10b-5p and miR-21-5p were independently associated with poor overall survival (with hazard ratio [95% confidence interval]: 2.42 (1.45 - 4.04), P = 0.001; 2.22 (1.18 - 4.16), P = 0.013; 2.12 (1.28 - 3.49), P = 0.003, respectively). When compared to the clinical prognostic variables only model, adding the three exosomal miRNA signatures significantly improved survival predictive accuracy with an increase of time-dependent area under the receiver operating characteristic curve from 0.88 to 0.91 (P=0.015). Our results indicated that plasma exosomal miR-23b-3p, miR-10b-5p and miR-21-5p are promising non-invasive prognostic biomarkers of NSCLC.

A potent antitumor Zn2+ tetraazamacrocycle complex targeting DNA: the fluorescent recognition, interaction and apoptosis studies.

A Zn(2+) tetraazamacrocycle complex (2) bearing three naphthalene moieties has been prepared. Complex 2 recognizes, binds and causes damage to DNA, and shows considerable cytotoxicity against human cervical (HeLa), breast (MCF-7) and lung (NCI-H157) cancer cell lines with a different apoptotic pathway from that of cisplatin.

Transition metal ions and selenite modulate the methylation of arsenite by the recombinant human arsenic (+3 oxidation state) methyltransferase (hAS3MT).

This report demonstrates that transition metal ions and selenite affect the arsenite methylation by the recombinant human arsenic (+3 oxidation state) methyltransferase (hAS3MT) in vitro. Co(2+), Mn(2+), and Zn(2+) inhibited the arsenite methylation by hAS3MT in a concentration-dependent manner and the kinetics indicated Co(2+) and Mn(2+) to be mixed (competitive and non-competitive) inhibitors while Zn(2+) to be a competitive inhibitor. However, only a high concentration of Fe(2+) could restrain the methylation. UV-visible, CD and fluorescence spectroscopy were used to study the interactions between the metal ions above and hAS3MT. Further studies showed that neither superoxide anion nor hydrogen peroxide was involved in the transition metal ion or selenite inhibition of hAS3MT activity. The inhibition of arsenite methylating activity of hAS3MT by selenite was reversed by 2mM DTT (dithiothreitol) but neither by cysteine nor by beta-mercaptoethanol. Whereas, besides DTT, cysteine can also prevent the inhibition of hAS3MT activity by Co(2+), Mn(2+), and Zn(2+). Free Cys residues were involved in the interactions of transition metal ions or selenite with hAS3MT. It is proposed that the inhibitory effect of the ions (Co(2+), Mn(2+), and Zn(2+)) or selenite on hAS3MT activity might be via the interactions of them with free Cys residues in hAS3MT to form inactive protein adducts.

Structure-function roles of four cysteine residues in the human arsenic (+3 oxidation state) methyltransferase (hAS3MT) by site-directed mutagenesis.

Cysteine (Cys) residues are often crucial to the function and structure of proteins. Cys157 and Cys207 in recombinant mouse arsenic (+3 oxidation state) methyltransferase (AS3MT) are shown to be related to enzyme activity and considered to be the catalytic sites. The roles of some conserved Cys residues in the N-terminal region of the rat AS3MT also have been examined. However, little is known about the roles of the Cys residues in the middle region. The metabolism of inorganic arsenic in human is different from rat and mouse in some aspects though the AS3MT has a high degree of similarity in these species. In order to determine whether the Cys156 and Cys206 (corresponding to the catalytic sites, Cys157 and Cys207 in the mouse AS3MT) in the hAS3MT act as the catalytic sites and to study the roles of the Cys residues (Cys226 and Cys250) near the catalytic center in the middle region, we designed and prepared four mutants (C156S, C206S, C226S, and C250S) in which one Cys residue replaced by serine by PCR-based site-directed mutagenesis. The native form and cysteine/serine mutants were assayed for enzyme activity, free thiols, and the secondary structures by circular dichroism and Fourier transform infrared. Our data show that, besides C156S and C206S, C250S is another potential important site. C226S seems to have the same action as the wild-type hAS3MT with the consistent K(M) and V(max) values. Meanwhile, selenium can also inhibit the methylation of inorganic arsenic by C226S. All the mutants except C226S are calculated to have dramatic changes in the secondary structures. Cys250 might form an intramolecular disulfide bond with another Cys residue. These findings demonstrate that Cys residues at positions 156, 206, and 250 play important roles in the enzymatic function and structure of the hAS3MT.