Significance: Using in vitro and in vivo approaches, this report demonstrated the increased METTL3 expression and m ⁶ A hypermethylation in response to disturbed flow and oscillatory shear stress. METTL3 hypermethylates m ⁶ A sites at various downstream targets, up-regulates NLRP1 and down-regulates KLF4, and elicits atherogenic responses. Collectively, METTL3 and m ⁶ A hypermethylation epigenetically regulates the atherogenic gene expression and phenotypes in the initiation of atherosclerosis. Our data may enlighten the field of RNA epigenetics in the pathogenic mechanisms of heart diseases.

Lung cancer (LC) causes the majority of cancer-related deaths. Circular RNAs (circRNAs) were reported to play roles in cancers by targeting pro- and anti-oncogenic miRNAs. However, the mechanisms of circRNAs in LC progression and their prognostic value of treatment response remain unclear. By using next generation sequencing (NGS) of LC cell lines’ transcriptomes, we identified highly overexpressed hsa_circ_0000190 and hsa_circ_000164 as potential biomarkers. By using the highly sensitive RT-ddPCR method, these circRNAs were shown to be secreted by cell lines and were detected in human blood. Clinical validation by RT-ddPCR was carried out on 272 (231 LC patients and 41 controls) blood samples. Higher hsa_circ_0000190 levels were associated with larger tumor size (p < 0.0001), worse histological type of adenocarcinoma (p = 0.0028), later stage (p < 0.0001), more distant metastatic organs (p = 0.0039), extrathoracic metastasis (p = 0.0004), and poor survival (p = 0.047) and prognosis. Using liquid biopsy-based RT-ddPCR, we discovered the correlation between increased hsa_circ_0000190 plasma level (p < 0.0001) and higher programmed death-ligand 1 (PD-L1) level in tumor (p = 0.0283). Notably, long-term follow-up of the immunotherapy treated cases showed that upregulated plasma hsa_circ_0000190 level correlated with poor response to systemic therapy and immunotherapy (p = 0.0002, 0.0058, respectively). Secretory circRNAs are detectable in blood by LB-based RT-ddPCR and may serve as blood-based biomarkers to monitor disease progression and treatment efficacy.

Background: Glioblastoma (GBM) is the most lethal brain tumor characterized by high morbidity and limited treatment options. Tumor malignancy is usually associated with the epigenetic marks, which coordinate gene expression to ascertain relevant phenotypes. One of such marks is m6A modification of RNA, whose functional effects are dependent on the YTH family m6A reader proteins. Methods and results: In this study, we investigated the expression of five YTH family proteins in different GBM microarray datasets from the Oncomine database, and identified YTHDF1 as the most highly overexpressed member of this family in GBM. By performing the knockdown of YTHDF1 in a GBM cell line, we found that it positively regulates proliferation, chemoresistance and cancer stem cell-like properties. Musashi-1 (MSI1) is a postranscriptional gene expression regulator associated with high oncogenicity in GBM. By knocking down and overexpressing MSI1, we found that it positively regulates YTHDF1 expression. The inhibitory effects imposed on the processes of proliferation and migration by YTHDF1 knockdown were shown to be partially rescued by concomitant overexpression of MSI1. MSI1 and YTHDF1 were shown to be positively correlated in clinical glioma samples, and their concomitant upregulation was associated with decreased survival of glioma patients. We identified the direct regulation of YTHDF1 by MSI1. Conclusions: Given the fact that both proteins are master regulators of gene expression, and both of them are unfavorable factors in GBM, we suggest that in any future studies aimed to uncover the prognostic value and therapy potential, these two proteins should be considered together.

Lung cancer is the leading cause of death from cancer in Taiwan and throughout the world. Immunotherapy has revealed promising and significant efficacy in NSCLC, through immune checkpoint inhibition by blocking programmed cell death protein (PD)-1/PD-1 ligand (PD-L1) signaling pathway to restore patients’ T-cell immunity. One novel type of long, non-coding RNAs, circular RNAs (circRNAs), are endogenous, stable, and widely expressed in tissues, saliva, blood, urine, and exosomes. Our previous results revealed that the plasma level of hsa_circ_0000190 can be monitored by liquid-biopsy-based droplet digital PCR and may serve as a valuable blood-based biomarker to monitor the disease progression and the efficacy of immunotherapy. In this study, hsa_circ_0000190 was shown to increase the PD-L1 mRNA-mediated soluble PD-L1 (sPD-L1) expression, consequently interfering with the efficacy of anti-PD-L1 antibody and T-cell activation, which may result in immunotherapy resistance and poor outcome. Our results unraveled that hsa_circ_0000190 facilitated the tumorigenesis and immune evasion of NSCLC by upregulating sPD-L1 expression, potentially developing a different aspect in elucidating the molecular immunopathogenesis of NSCLC. Hsa_circ_0000190 upregulation can be an effective indicator for the progression of NSCLC, and hsa_circ_0000190 downregulation may possess a potential therapeutic value for the treatment of NSCLC in combination with immunotherapy.

Background: China announced an outbreak of new coronavirus in the city of Wuhan on December 31, 2019; lash to now, the virus transmission has become pandemic worldwide. Severe cases from the Huanan Seafood Wholesale market in Wuhan were confirmed pneumonia with a novel coronavirus (2019-nCoV). Understanding the molecular mechanisms of genome selection and packaging is critical for developing antiviral strategies. Thus, we defined the correlation in 10 severe acute respiratory syndrome coronavirus (SARS-CoV2) sequences from different countries to analyze the genomic patterns of disease origin and evolution aiming for developing new control pandemic processes. Methods: We apply genomic analysis to observe SARS-CoV2 sequences from GenBank (http://www.ncbi.nim.nih.gov/genebank/): MN 908947 (China, C1), MN985325 (USA: WA, UW), MN996527 (China, C2), MT007544 (Australia: Victoria, A1), MT027064 (USA: CA, UC), MT039890 (South Korea, K1), MT066175 (Taiwan, T1), MT066176 (Taiwan, T2), LC528232 (Japan, J1), and LC528233 (Japan, J2) for genomic sequence alignment analysis. Multiple Sequence Alignment by Clustalw (https://www.genome.jp/tools-bin/clustalw) web service is applied as our alignment tool. Results: We analyzed 10 sequences from the National Center for Biotechnology Information (NCBI) database by genome alignment and found no difference in amino acid sequences within M and N proteins. There are two amino acid variances in the spike (S) protein region. One mutation found from the South Korea sequence is verified. Two possible “L” and “S” SNPs found in ORF1ab and ORF8 regions are detected. Conclusion: We performed genomic analysis and comparative multiple sequences of SARS-CoV2. Studies about the biological symptoms of SARS-CoV2 in clinic animals and humans will manipulate an understanding on the origin of pandemic crisis.

The cells of the central nervous system (CNS) show irreversible features after injury, and they could be re-established by stem cells. Induced pluripotent stem cells (iPSCs) may be generated from adult mammalian cells and gain pluripotency to differentiate into various lineages and functional cells. Non-viral carriers for delivering differentiation factors to transform iPSCs into neuronal cells are very desirable. In this study, mesoporous silica nanoparticles (MSNs) are used to co-deliver Nurr1 plasmid DNA (pNurr1) and Rex1 siRNA (siRex1) into iPSCs to achieve dopaminergic neuron differentiation. Sixty hours after treatment with siRex1 and pNurr1, the co-delivery of pNurr1 and siRex1 enhanced the Nurr1 gene expression three-fold, compared to the delivery of the plasmid pNurr1 only. The dopaminergic neuron-related protein level was identified using immunofluorescence staining and flow cytometry analysis, and there were 89.9% ± 0.5% tyrosine hydroxylase-expressing cells and 88.5% ± 2.0% dopamine transporter-expressing cells differentiated from iPSCs after transfection by MSNs. An ELISA was also used to determine the maturation of functional neurons, and there was 12.19 ng mL⁻¹ dopamine released from cells after transfection by MSNs. These results demonstrate that MSNs are good non-viral nanocarriers for dual delivery of pNurr1 and siRex1 to significantly enhance the generation of dopaminergic neurons from iPSCs.