Identification of a Plasma Exosomal lncRNA- and circRNA-Based ceRNA Regulatory Network in Patients With Lung Adenocarcinoma.

Exosomes have been established to be enriched with various long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) that exert various biological effects. However, the lncRNA- and circRNA-mediated coexpression competing endogenous RNA (ceRNA) regulatory network in exosomes derived from the plasma of patients with lung adenocarcinoma (LUAD) remains elusive. This study enrolled nine patients with lung adenocarcinoma and three healthy individuals, and the differential expression of messenger RNAs (mRNAs), lncRNAs, and circRNAs was detected using microarray analysis, while microRNAs (miRNAs) were detected through RNA sequencing. Additionally, bioinformatics algorithms were applied to evaluate the lncRNA-miRNA-mRNAs/circRNA-miRNA-mRNA network. Differentially expressed cicRNAs were identified via quantitative reverse transcription polymerase chain reaction (RT-qPCR). A total of 1016 lncRNAs, 1396 circRNAs, 45 miRNAs, and 699 mRNAs were differentially expressed in the plasma exosomes of patients with LUAD compared with healthy controls. Among them, 881 lncRNAs were upregulated and 135 were downregulated, 916 circRNAs were upregulated while 480 were downregulated, 45 miRNAs were upregulated while none were downregulated, and 591 mRNAs were upregulated while 108 were downregulated (p ≤ 0.05, and fold change ≥ 2). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed the biological functions of differentially expressed RNAs. Meanwhile, the RNA networks displayed the regulatory relationship between dysregulated RNAs. Finally, RT-qPCR validated that the expression of circ-0033861, circ-0043273, and circ-0011959 was upregulated in the plasma exosome of patients with LUAD compared to healthy controls (p = 0.0327, p = 0.0002, p = 0.0437, respectively). This study proposed a newly discovered ncRNA-miRNA-mRNA/circRNA-miRNA-mRNA ceRNA network and identified that the expression of circulating circ-0033861, circ-0043273, and circ-0011959 was up-regulated in the plasma exosomes of patients with LUAD, offering valuable insights for exploring the potential function of exosomal noncoding RNA and identifying potential biomarkers for LUAD.

Zhu W ，Zhang H ，Tang L ，Fang K ，Lin N ，Huang Y ，Zhang Y ，Le H ... -  《-》

Circular RNAs expression profiles in plasma exosomes from early-stage lung adenocarcinoma and the potential biomarkers.

This study aimed to identify differential circular RNA (circRNA) in the plasma exosomes of patients with lung adenocarcinoma (LUAD) using high-throughput sequencing. First, exosomes were isolated using an exosome isolation kit and confirmed by Western blotting, transmission electron microscopy, and NanoSight Assay. Subsequently, plasma circRNA expression profiles were screened by high-throughput sequencing and confirmed by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR) and Sanger sequencing. Finally, the circRNA-miRNA-mRNA network was performed to forecast the potential function of circRNAs. The result of high-throughput sequencing data documented that 182 differentially expressed exosomal circRNAs in all were screened, which included 105 that were upregulated and 78 that were downregulated in LUAD patients plasma compared with controls. The four upregulated circRNAs including circ_0001492, circ_0001346, circ_0000690, and circ_0001439 were identical to the sequencing data by qRT-PCR, and their latent circRNA-miRNA-mRNA interactions were exhibited. Taken together, our study firstly revealed the altered exosomal circRNA expression from plasma samples in patients with LUAD and supports the need for exploring their potential as biomarkers and the pathological effects of lung cancer.

Chen F ，Huang C ，Wu Q ，Jiang L ，Chen S ，Chen L ... -  《-》

CircRNA, lncRNA, and mRNA profiles of umbilical cord blood exosomes from preterm newborns showing bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) represents a multifactorial chronic pulmonary pathology and a major factor causing premature illness and death. The therapeutic role of exosomes in BPD has been feverishly investigated. Meanwhile, the potential roles of exosomal circRNAs, lncRNAs, and mRNAs in umbilical cord blood (UCB) serum have not been studied. This study aimed to detect the expression profiles of circRNAs, lncRNAs, and mRNAs in UCB-derived exosomes of infants with BPD. Microarray analysis was performed to compare the RNA profiles of UCB-derived exosomes of a preterm newborn with (BPD group) and without (non-BPD, NBPD group) BPD. Then, circRNA/lncRNA-miRNA-mRNA co-expression networks were built to determine their association with BPD. In addition, cell counting kit-8 (CCK-8) assay was used to evaluate the proliferation of lipopolysaccharide (LPS)-induced human bronchial epithelial cells (BEAS-2B cells) and human umbilical vein endothelial cells (HUVECs). The levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in LPS-induced BEAS-2B cells and HUVECs were assessed through Western blot analysis. Then, quantitative reverse transcription-polymerase chain reaction assay was used to evaluate the expression levels of four differentially expressed circRNAs (hsa_circ_0086913, hsa_circ_0049170, hsa_circ_0087059, and hsa_circ_0065188) and two lncRNAs (small nucleolar RNA host gene 20 (SNHG20) and LINC00582) detected in LPS-induced BEAS-2B cells or HUVECs. A total of 317 circRNAs, 104 lncRNAs, and 135 mRNAs showed significant differential expression in UCB-derived exosomes of preterm infants with BPD compared with those with NBPD. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted to examine differentially expressed exosomal circRNAs, lncRNAs, and mRNAs. The results showed that the GO terms and KEGG pathways mostly involving differentially expressed exosomal RNAs were closely associated with endothelial or epithelial cell development. In vitro, CCK-8 and Western blot assays revealed that LPS remarkably inhibited the viability and promoted inflammatory responses (TNF-α and IL-1β) of BEAS-2B cells or HUVECs. The expression levels of circRNAs hsa_circ_0049170 and hsa_circ_0087059 were upregulated in LPS-induced BEAS-2B cells; the expression level of hsa_circ_0086913 was upregulated and that of hsa_circ_0065188 was downregulated in LPS-induced HUVECs. Moreover, the expression level of lncRNA SNHG20 was upregulated and that of LINC00582 was downregulated in LPS-induced BEAS-2B cells. Further, 455 circRNA/lncRNA-miRNA-mRNA interaction networks were predicted, including hsa_circ_0086913/hsa-miR-103a-3p/transmembrane 4 L six family member 1 (TM4SF1) and lncRNA-SNHG20/hsa-miR-6720-5p/spermine synthase (SMS) networks, which may take part in BPD. This study provided a systematic perspective on UCB-derived exosomal circRNAs and lncRNAs and laid an important foundation for further investigating the potential biological functions of exosomal circRNAs and lncRNAs in BPD. • BPD represents a multifactorial chronic pulmonary pathology and a major factor causing premature illness and death. • The therapeutic role of exosomes in BPD has been feverishly investigated, and exosomal RNAs were ignored. • The profiles of UCB-derived exosomal circRNAs, lncRNAs, and mRNAs were performed. • Several differentially expressed circRNAs and lncRNAs were identified in LPS-induced BEAS-2B cells and HUVECs.

Wang Y ，Wang X ，Xu Q ，Yin J ，Wang H ，Zhang L ... -  《-》

A two-circular RNA signature as a noninvasive diagnostic biomarker for lung adenocarcinoma.

Liu XX ，Yang YE ，Liu X ，Zhang MY ，Li R ，Yin YH ，Qu YQ ... -  《Journal of Translational Medicine》

Construction and comprehensive analysis of a ceRNA network to reveal potential prognostic biomarkers for lung adenocarcinoma.

More and more studies have proven that circular RNAs (circRNAs) play vital roles in cancer development via sponging miRNAs. However, the expression pattern of competing endogenous RNA (ceRNA) in lung adenocarcinoma (LUAD) remains largely unclear. The current study explored functional roles and the regulatory mechanisms of circRNA as ceRNAs in LUAD and their potential impact on LUAD patient prognosis. In this study, we systematically screened differential expression circRNAs (DEcircRNAs), miRNAs (DEmiRNAs) and mRNAs (DEGs) associated with LUAD. Then, DEcircRNAs, DEmiRNAs and DEGs were selected to construct a circRNA-miRNA-mRNA prognosis-related regulatory network based on interaction information from the ENCORI database. Subsequently, the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed on the genes in the network to predict the potential underlying mechanisms and functions of circRNAs in LUAD. In addition, Kaplan-Meier survival analysis was performed to evaluate clinical outcomes of LUAD patients, and drug sensitivity analysis was used to screen potential biomarkers for drug treatment of patients with LUAD. As a result, 10 circRNAs were aberrantly expressed in LUAD tissues. The ceRNA network was built, which included 3 DEcircRNAs, 6 DEmiRNAs and 157 DEGs. The DEGs in the ceRNA network of hsa_circ_0049271 enriched in biological processes of cell proliferation and the Jak-STAT signaling pathway. We also detected 7 mRNAs in the ceRNA network of hsa_circ_0049271 that were significantly associated with the overall survival of LUAD patients (P < 0.05). Importantly, four genes (PDGFB, CCND2, CTF1, IL7R) identified were strongly associated with STAT3 activation and drugs sensitivity in GDSC. In summary, a ceRNA network of hsa_circ_0049271 was successfully constructed, which including one circRNA, two miRNAs, and seven mRNAs. Seven mRNAs (PDGFB, TNFRSF19, CCND2, CTF1, IL11RA, IL7R and MAOA) were remarkably associated with the prognosis of LUAD patients. Among seven mRNA species, four genes (PDGFB, CCND2, CTF1, and IL7R) could be considered as drug targets in LUAD. Our research will provide new insights into the prognosis-related ceRNA network in LUAD.

Gao L ，Zhang L 《BMC CANCER》