Extracellular RNA profiles in non-small cell lung cancer plasma.

Background: Non-small cell lung cancer (NSCLC) has a high mortality rate and poor prognosis. The early detection of high-risk patients is essential to improve patient prognosis. Thus, the identification of a non-invasive, non-radiative, convenient, and fast diagnostic approach should be a top priority in NSCLC research. Circulating extracellular RNAs (exRNAs) in the plasma are potential biomarkers for NSCLC. Methods: We used RNA-sequencing (RNA-seq) technology to explore the NSCLC-related RNAs, especially the circular RNAs (circRNAs). The circRNA-targeted micro RNAs (miRNAs) were predicted using 3 circRNA databases [i.e., the Cancer-Specific CircRNA Database (CSCD), circBank, and Circular RNA Interactome]. The circRNA-miRNA-messenger RNA (mRNA) network was constructed using Cytoscape V3.8.0 (Cytoscape Consortium, San Diego, CA, USA). The expression levels of some differentially expressed genes were validated by a quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Results: The results showed that the RNA biotypes of the mitochondrial ribosomal RNAs (mt-rRNAs) and mitochondrial transfer RNAs (mt-tRNAs) were upregulated in the NSCLC plasma. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) terms of the differentially expressed transcripts of NSCLC included oxidative phosphorylation, proton transmembrane transport, and the response to oxidative stress. Additionally, the qRT-PCR validation indicated that hsa_circ_0000722 had significantly higher expression in the NSCLC plasma than the control plasma, but hsa_circ_0006156 did not differ between the NSCLC plasma and the control plasma. The expression levels of miR-324-5p and miR-326 were higher in the NSCLC plasma than the control plasma. Conclusions: In this study, an exRNA-sequencing strategy was used to identify the expression of NSCLC-specific transcription factors in clinical plasma samples, and hsa_circ_0000722 and hsa-miR-324-5p were identified as potential biomarkers in NSCLC.

Single-cell multi-omics sequencing and its application in tumor heterogeneity.

In recent years, the emergence and development of single-cell sequencing technologies have provided unprecedented opportunities to analyze deoxyribonucleic acid, ribonucleic acid and proteins at single-cell resolution. The advancements and reduced costs of high-throughput technologies allow for parallel sequencing of multiple molecular layers from a single cell, providing a comprehensive insight into the biological state and behavioral mechanisms of cells through the integration of genomics, transcriptomics, epigenomics and proteomics information. Researchers are actively working to further improve the cost-effectiveness, stability and high-throughput capabilities of single-cell multi-omics sequencing technologies and exploring their potential in precision medicine through clinical diagnostics. This review aims to survey the cutting-edge advancements in single-cell multi-omics sequencing, summarizing the representative technologies and their applications in profiling complex diseases, with a particular focus on tumors.

N-acetyl-L-cysteine attenuated the toxicity of ZIF-8 on EA.hy926 endothelial cells by wnt/ß-catenin pathway.

As kinds of porous crystalline compounds, zeolitic imidazolate frameworks (ZIFs) have been developed quickly and attracted considerable attention for use in nano drug delivery systems, which raised concerns about cardiovascular disorders. At the present, the cytotoxic mechanism of ZIFs in cardiovascular disorders was still unclear. Our experiment explored the toxicity of ZIF-8, a typical kind of ZIFs, on human EA.hy926 vascular endothelial cells. The cell viability, ROS formation, apoptosis level, inflammatory response level, wound healing ability and atherosclerosis-related indicators of EA.hy926 endothelial cells were analyzed after ZIF-8 treatment. Meanwhile, we evaluated the ability of antioxidant N-Acetyl-L-cysteine (NAC) to attenuate the toxicity of ZIF-8 on EA.hy926 endothelial cells. As results, NAC attenuated ROS formation, cell apoptosis, LDH formation and endothelial dysfunction caused by ZIF-8. As the Wnt/ß-catenin pathway was involved in endothelial cell dysfunction, we also studied the expression level of ß-catenin and LEF1 in ZIF-8 and/or NAC treated EA.hy926 cells. As expected, ZIF-8 increased the protein expressions of ß-catenin and LEF1in the IC50 group, which was significantly inhibited by co-treatment with NAC. Taken together, this study could help improve our understanding about the mechanism of ZIF-8-induced endothelial cells injury and NAC had therapeutic potential in preventing ZIF-8-associated endothelial dysfunction by wnt/ß-catenin pathway.

Analysis approaches for the identification and prediction of N6-methyladenosine sites.

The global dynamics in a variety of biological processes can be revealed by mapping transcriptional m6A sites, in particular full-transcriptome m6A. And individual m6A sites have contributed to biological function, which can be evaluated by stoichiometric information obtained from the single nucleotide resolution. Currently, the identification of m6A sites is mainly carried out by experiment and prediction methods, based on high-throughput sequencing and machine learning model respectively. This review summarizes the recent topics and progress made in bioinformatics methods of deciphering the m6A methylation, including the experimental detection of m6A methylation sites, techniques of data analysis, the way of predicting m6A methylation sites, m6A methylation databases, and detection of m6A modification in circRNA. At the end, the essay makes a brief discussion for the development perspective in this area.

Tumor-derived exosomal HOTAIRM1 regulates SPON2 in CAFs to promote progression of lung adenocarcinoma.

OBJECTIVE: SPON2 is one of the extracellular matrix proteins, which is closely related to the progression of a variety of tumors including non-small cell lung cancer (NSCLC), but its upstream regulation mechanism remains unclear. Our research aims to find the specific regulatory pathway of SPON2 by exploring the potential crosstalk between tumor cells and cancer-associated fibroblasts (CAFs) in tumor microenvironment (TME) of NSCLC. METHODS: We analyzed T1 lung adenocarcinoma samples from TCGA and screened extracellular matrix proteins that indicate poor prognosis. Expression level of SPON2 was verified by qPCR in clinical samples. The exosomes of NSCLC cell supernatant were extracted and identified by nanoparticle tracking analysis (NTA) and transmission electron microscope, western blots. The exosomes and CAFs were co-cultured, and cell migration and Matrigel invasion assay were used to evaluate the effect of CAFs on the migration and invasion of NSCLC cells. The interaction between LncRNA and miRNA was verified by Targetscan prediction, luciferase reporter assay, and RNA binding protein immunoprecipitation (RIP). RESULTS: We found that the expression of SPON2 was up-regulated in clinical T1a stage NSCLC patients. The expression of lnc HOTAIRM1 (HOTAIRM1) in exosomes secreted by NSCLC tissues increased. After exosomal HOTAIRM1 entered CAFs, HOTAIRM1 can adsorb miR-328-5p to up-regulate the expression of SPON2 in CAFs. Up-regulation of SPON2 in CAFs could promote the migration and invasion of NSCLC cells. CONCLUSION: Tumor-derived exosomal HOTAIRM1 can transfer into CAFs and competitively adsorb miR-328-5p, and regulate the SPON2 expression of CAFs cells, ultimately promote the progression of NSCLC. The discovery of this regulatory pathway can provide a new potential therapeutic target for the diagnosis and treatment of NSCLC.

Nigirpexin E, a new azaphilone derivative with anti-tobacco mosaic virus activity from soil-derived fungus Trichoderma afroharzianum LTR-2.

A new compound classified as one new azaphilone derivative, nigirpexin E (1), was obtained from the soil-derived fungus Trichoderma afroharzianum LTR-2, together with seven known compounds (2-8). The structures of 1-8 were determined by their HRESIMS, optical rotation, and NMR spectroscopic data. The absolute configuration of nigirpexin E (1) was determined on the basis of comparisons of experimental and theoretically calculated ECD spectra. Compound 3 was firstly isolated from Trichoderma. Bioactivities of the isolated compounds were assayed their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compound 1 exhibited significant inactivation effect against TMV with an inhibition rate of 67.25% (0.5 mg ml-1), which was higher than that of positive control ribavirin (56.74%). This is the first report of the anti-TMV activity of azaphilone derivatives.

Tumor-associated macrophages secret exosomal miR-155 and miR-196a-5p to promote metastasis of non-small-cell lung cancer.

BACKGROUND: Understanding the molecular basis underlying metastasis of non-small cell lung cancer (NSCLC) may provide a new therapeutic modality for the treatment of NSCLC. However, the mechanisms by which tumor-associated macrophages (TAMs) affect NSCLC metastasis remain undefined. In this study, we aimed to discover a novel regulatory pathway involved in NSCLC metastasis. METHODS: Cell Counting Kit-8 (CCK-8), Transwell, western blot assays were used to assess cell viability, migration, invasion and epithelial-mesenchymal transition (EMT). Exosomes from macrophages medium were characterized, and in vitro cell coculture was further conducted to investigate M2 derived exosomes mediated crosstalk between TAMs and tumor cells. Besides, miRNA microarray was used to analyze miRNA expression profiles of M0 and M2 derived exosomes. Luciferase reporter assay was used to verify the potential binding between miRNA and mRNA. Moreover, 6-week-old male BALB/c nude mice were performed to establish transplantation tumor model using tail vein injection. Hematoxylin & eosin staining was used to detect the metastasis of tumor tissues. RESULTS: We found that M2 TAMs were the main TAMs in metastatic tissues of NSCLC patients and exosomes derived from M2 TAMs were able to promote cell viability, cell migration, cell invasion and EMT in NSCLC. We demonstrated that miR-155 and miR-196a-5p were abundant in M2 TAMs and exosomes secreted by M2 TAMs. Functional experiments demonstrated that the deletion of miR-155 and miR-196a-5p in M2 TAMs significantly prevented NSCLC metastasis in vitro and in vivo. To clarify the mechanism governing miR-155 and miR-196a-5p from M2 TAMs, we carried out bioinformatics analysis to predict potential target genes. Mechanistically, miR-155 and miR-196a-5p directly bound to the 3'-UTR of Ras association domain family member 4 (RASSF4), and negatively regulating RASSF4 expression. At last, rescue assays demonstrated that miR-155 and miR-196a-5p exerted its performance by RASSF4. CONCLUSIONS: Overall, we revealed a new regulatory pathway that was M2 TAMs secreted exosomal miR-155 and miR-196a-5p to promote NSCLC metastasis. This dynamic and reciprocal cross-talk between NSCLC and macrophages innovatively provided a potential opportunity for diagnosis and treatment of NSCLC.

Denoising Autoencoder, A Deep Learning Algorithm, Aids the Identification of A Novel Molecular Signature of Lung Adenocarcinoma.

Precise biomarker development is a key step in disease management. However, most of the published biomarkers were derived from a relatively small number of samples with supervised approaches. Recent advances in unsupervised machine learning promise to leverage very large datasets for making better predictions of disease biomarkers. Denoising autoencoder (DA) is one of the unsupervised deep learning algorithms, which is a stochastic version of autoencoder techniques. The principle of DA is to force the hidden layer of autoencoder to capture more robust features by reconstructing a clean input from a corrupted one. Here, a DA model was applied to analyze integrated transcriptomic data from 13 published lung cancer studies, which consisted of 1916 human lung tissue samples. Using DA, we discovered a molecular signature composed of multiple genes for lung adenocarcinoma (ADC). In independent validation cohorts, the proposed molecular signature is proved to be an effective classifier for lung cancer histological subtypes. Also, this signature successfully predicts clinical outcome in lung ADC, which is independent of traditional prognostic factors. More importantly, this signature exhibits a superior prognostic power compared with the other published prognostic genes. Our study suggests that unsupervised learning is helpful for biomarker development in the era of precision medicine.

MiR-486-5p Serves as a Good Biomarker in Nonsmall Cell Lung Cancer and Suppresses Cell Growth With the Involvement of a Target PIK3R1.

MicroRNAs are a class of noncoding RNAs that can be involved in the regulation of gene expression in cancers, including lung cancer. Our previous research has shown that miR-486-5p is one of the most downregulated microRNAs in tissue and serum samples of lung cancer as a good diagnostic biomarker. The objective of this study is to investigate the roles of miR-486-5p in the progression of lung cancer. In this study, miR-486-5p was further validated to be significantly downregulated in additional nonsmall cell lung cancer (NSCLC) tissue, serum, and cell samples by quantitative reverse transcription-polymerase chain reaction (RT-PCR), and the expression level of miR-486-5p was significantly associated with clinical phenotype of NSCLC. The PIK3R1 gene was confirmed to be a direct target of miR-486-5p by dual-luciferase reporter assay, and the expression level of miR-486-5p was inversely correlated with that of PIK3R1 in tumor tissues (r = -0.774, p < 0.01). Overexpressed miR-486-5p effectively inhibited cell proliferation and invasion and successfully induced apoptosis in vitro. PIK3R1 was involved in the suppression of miR-486-5p on cell growth. It can be concluded that miR-486-5p may act as a tumor suppressor contributing to the progression of NSCLC, and miR-486-5p would be a diagnostic and prognostic biomarker and a potential therapeutic target for lung cancer.

A Pathway-Based Strategy to Identify Biomarkers for Lung Cancer Diagnosis and Prognosis.

Current research has identified several potential biomarkers for lung cancer diagnosis or prognosis. However, most of these biomarkers are derived from a relatively small number of samples using algorithms at the gene level. Hence, gene expression signatures discovered in these studies have little overlaps. In this study, we proposed a new strategy to identify biomarkers from multiple datasets at the pathway level. We integrated the genome-wide expression data of lung cancer tissues from 13 published studies and applied our strategy to identify lung cancer diagnostic and prognostic biomarkers. We identified a 32-gene signature that differentiates lung adenocarcinomas from other lung cancer subtypes. We also discovered a 43-gene signature that can predict the outcome of human lung cancers. We tested their performance in several independent cohorts, which confirmed their robust prognostic and diagnostic power. Furthermore, we showed that the proposed gene expression signatures were independent of several traditional clinical indicators in lung cancer management. Our results suggest that the pathway-based strategy is useful to identify transcriptomic biomarkers from large-scale gene expression datasets that were collected from multiple sources.

Personalized Peptide Arrays for Detection of HLA Alloantibodies in Organ Transplantation.

In organ transplantation, the function and longevity of the graft critically rely on the success of controlling immunological rejection reactivity against human leukocyte antigens (HLA). Histocompatibility guidelines are based on laboratory tests of anti-HLA immunity, which presents either as pre-existing or de novo generated HLA antibodies that constitute a major transplantation barrier. Current tests are built on a single-antigen beads (SAB) platform using a fixed set of ~100 preselected recombinant HLA antigens to probe transplant sera. However, in humans there exist a far greater variety of HLA types, with no two individuals other than identical twins who can share the same combination of HLA sequences. While advanced technologies for HLA typing and direct sequencing can precisely capture any mismatches in DNA sequence between a donor's and recipient's HLA, the SAB assay, due to its limited variety in sequence representation, is unable to precisely detect alloantibodies specifically against the donor HLA mismatches. We sought to develop a complementary method using a different technology to detect and characterize anti-donor HLA antibodies on a personalized basis. The screening tool is a custom peptide array of donor HLA-derived sequences for probing post-transplant sera of the organ recipient to assess the risk for antibody-mediated rejection. On a single array for one donor-recipient pair, up to 600 unique peptides are made based on the donor's HLA protein sequences, each peptide carrying at least one mismatched residue in a 15-amino acid sequence. In our pilot experiments to compare antigen patterns for pre- and post-transplant sera on these arrays, we were able to detect anti-HLA signals with the resolution that also allowed us to pinpoint the immune epitopes involved. These personalized antigen arrays allow high-resolution detection of donor-specific HLA epitopes in organ transplantation.

Isolation, structures and bioactivities of the polysaccharides from jujube fruit (Ziziphus jujuba Mill.): A review.

Jujube (Ziziphus Jujuba Mill.) has been eaten as a fruit and nutraceutical food in China for thousands of years. Recent phytochemical and pharmacological studies have shown that the polysaccharides are one of major biologically active components of the jujube fruit and have various biological effects, including immunomodulatory, antioxidant, antitumor, hepatoprotective, and hypoglycemic activities, and gastrointestinal-protective effects. Although the extraction and purification of jujube polysaccharides are tedious processes, including different steps of liquid- and solid-phase separation, the polysaccharides have been structurally characterized. However, the relationships between the structures and activities of the jujube polysaccharides are not well established. The purpose of the present review is to appraise the previous and current literature on the extraction, purification, structural characterization, and biological activities of jujube polysaccharides. This review should provide a useful bibliography for the further investigation, production, and application of jujube polysaccharides in functional foods and therapeutic agents.

Differentially Expressed miRNAs in Tumor, Adjacent, and Normal Tissues of Lung Adenocarcinoma.

Lung cancer is the leading cause of cancer deaths. Non-small-cell lung cancer (NSCLC) is the major type of lung cancer. The aim of this study was to characterize the expression profiles of miRNAs in adenocarcinoma (AC), one major subtype of NSCLC. In this study, the miRNAs were detected in normal, adjacent, and tumor tissues by next-generation sequencing. Then the expression levels of differential miRNAs were quantified by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). In the results, 259, 401, and 389 miRNAs were detected in tumor, adjacent, and normal tissues of pooled AC samples, respectively. In addition, for the first time we have found that miR-21-5p and miR-196a-5p were gradually upregulated from normal to adjacent to tumor tissues; miR-218-5p was gradually downregulated with 2-fold or greater change in AC tissues. These 3 miRNAs were validated by qRT-PCR. Lastly, we predicted target genes of these 3 miRNAs and enriched the potential functions and regulatory pathways. The aberrant miR-21-5p, miR-196a-5p, and miR-218-5p may become biomarkers for diagnosis and prognosis of lung adenocarcinoma. This research may be useful for lung adenocarcinoma diagnosis and the study of pathology in lung cancer.

The RNA expression signature of the HepG2 cell line as determined by the integrated analysis of miRNA and mRNA expression profiles.

Understanding miRNAs' regulatory networks and target genes could facilitate the development of therapies for human diseases such as cancer. Although much useful gene expression profiling data for tumor cell lines is available, microarray data for miRNAs and mRNAs in the human HepG2 cell line have only been compared with that of other cell lines separately. The relationship between miRNAs and mRNAs in integrated expression profiles for HepG2 cells is still unknown. To explore the miRNA-mRNA correlations in hepatocellular carcinoma (HCC) cells, we performed miRNA and mRNA expression profiling in HepG2 cells and normal liver HL-7702 cells at the genome scale using next-generation sequencing technology. We identified 193 miRNAs that are differentially expressed in these two cell lines. Of these, 89 miRNAs were down-regulated in HepG2 cells compared with HL-7702 cells, while 104 miRNAs were up-regulated. We also observed 3035 mRNAs that are significantly dys-regulated in HepG2 cells. We then performed an integrated analysis of the expression data for differentially expressed miRNAs and mRNAs and found several miRNA-mRNA pairs that are significantly correlated in HepG2 cells. Further analysis suggested that these differentially expressed genes were enriched in four tumorigenesis-related signaling pathways, namely, ErbB, JAK-STAT, mTOR, and WNT, which until now had not been fully reported. Our results could be helpful in understanding the mechanisms of HCC occurrence and development.

Evolutionary versatility of eukaryotic protein domains revealed by their bigram networks.

BACKGROUND: Protein domains are globular structures of independently folded polypeptides that exert catalytic or binding activities. Their sequences are recognized as evolutionary units that, through genome recombination, constitute protein repertoires of linkage patterns. Via mutations, domains acquire modified functions that contribute to the fitness of cells and organisms. Recent studies have addressed the evolutionary selection that may have shaped the functions of individual domains and the emergence of particular domain combinations, which led to new cellular functions in multi-cellular animals. This study focuses on modeling domain linkage globally and investigates evolutionary implications that may be revealed by novel computational analysis. RESULTS: A survey of 77 completely sequenced eukaryotic genomes implies a potential hierarchical and modular organization of biological functions in most living organisms. Domains in a genome or multiple genomes are modeled as a network of hetero-duplex covalent linkages, termed bigrams. A novel computational technique is introduced to decompose such networks, whereby the notion of domain "networking versatility" is derived and measured. The most and least "versatile" domains (termed "core domains" and "peripheral domains" respectively) are examined both computationally via sequence conservation measures and experimentally using selected domains. Our study suggests that such a versatility measure extracted from the bigram networks correlates with the adaptivity of domains during evolution, where the network core domains are highly adaptive, significantly contrasting the network peripheral domains. CONCLUSIONS: Domain recombination has played a major part in the evolution of eukaryotes attributing to genome complexity. From a system point of view, as the results of selection and constant refinement, networks of domain linkage are structured in a hierarchical modular fashion. Domains with high degree of networking versatility appear to be evolutionary adaptive, potentially through functional innovations. Domain bigram networks are informative as a model of biological functions. The networking versatility indices extracted from such networks for individual domains reflect the strength of evolutionary selection that the domains have experienced.

Global Egr1-miRNAs binding analysis in PMA-induced K562 cells using ChIP-Seq.

Although much is known about microRNAs' regulation in gene expression and their contributions in cell fate, to date, globally lineage-(cell-) specific identification of the binding events between a transcription factor and its targeting microRNA genes is still waiting for elucidation. In this paper, we performed a ChIP-Seq experiment to find the targeting microRNA genes of a transcription factor, Egr1, in human erythroleukemia cell line K562. We found Egr1 binding sites near the promoters of 124 distinct microRNA genes, accounting for about 42% of the miRNAs which have high-confidence predicted promoters (294). We also found EGR1 bind to another 63 pre-miRNAs. We chose 12 of the 187 microRNAs with Egr1 binding sites to perform ChIP-PCR assays and the positive binding signal from ChIP-PCR confirmed the ChIP-Seq results. Our experiments provide the first global binding profile between Egr1 and its targeting microRNA genes in PMA-treated K562 cells, which may facilitate the understanding of pathways controlling microRNA biology in this specific cell line.

Global analysis of in vivo EGR1-binding sites in erythroleukemia cell using chromatin immunoprecipitation and massively parallel sequencing.

Early growth response gene 1 (EGR1) has been implicated in megakaryocyte differentiation induced by phorbol ester. But the molecule mechanism of EGR1 in this process has not been widely investigated. The identification of direct EGR1 target genes in a global scale is critical for our understanding of how EGR1 contributes to this process. In this study, we provide a global survey on the binding location of EGR1 in the K562 cells using chromatin immunoprecipitation and massively parallel sequencing. Over 14 000 highly confident in vivo EGR1 binding sites were identified in phorbol 12-myristate 13-acetate-treated K562 cells. More than 70% of these genomic sites associated with EGR1 binding were located around annotated gene regions. Molecular functional classification of 6138 putative EGR1 target genes showed that the transcription factor class (695 of 6138; 11%) is the largest significantly enriched one. The results showed that a high coverage of the genome and a high positive rate achieve were achieved. This whole genome study on the EGR1 targets may provide a better understanding of the EGR1 regulated genes and the downstream pathway in megakaryocyte differentiation.