bioRxiv Science⌕ Search

Biology subjects

Nan, Y.

Publications and source records attributed to Nan, Y..

5 recordsLinked to original sources

m6A Demethylase FTO Stabilizes LINK-A to Exert Oncogenic Roles via MCM3-Mediated Cell Cycle Progression and HIF-1α Activation

RNA N6-methyladenosine (m6A) modification, balanced by methyltransferases and demethylases, has recently been shown to play critical roles in multiple cancers. However, the mechanism by which m6A modification regulates long noncoding RNA (lncRNA) stability and function during cancer progression remains unclear. Here, we show that m6A demethylase fat mass and obesity-associated protein (FTO) removes the m6A modification on long intergenic noncoding RNA for kinase activation (LINK-A) and stabilizes it to promote cell proliferation and cytotoxic chemotherapy resistance in esophageal squamous cell carcinoma (ESCC). Mechanistically, LINK-A enhances the interaction between minichromosome maintenance complex component 3 (MCM3) and cyclin-dependent kinase 1 (CDK1) to promote MCM3 phosphorylation by CDK1. MCM3 is a subunit of the hexameric protein complex and its phosphorylation facilitates loading of the MCM complex onto chromatin, which promotes cell cycle progression and subsequent cell proliferation. Meanwhile, LINK-A prevents the interaction of MCM3 and hypoxia-inducible factor 1 (HIF-1), abrogates MCM3-mediated transcriptional repression of HIF-1, and promotes glycolysis and chemoresistance of cancer cells. These results elucidate a mechanism whereby FTO-stabilized LINK-A plays oncogenic roles and present the FTO/LINK-A/MCM3/HIF-1 axis as a promising therapeutic target for ESCC.

cancer biology↗

Prion-like characteristics of Hepatitis E virus ORF3 protein are associated with virus release and pathogenesis

Hepatitis E virus (HEV) is a common causative agent of acute hepatitis. Due to the shortage of efficient in vitro model, the viral assembly and release processes are still poorly understood. In this study, we found that ORF3, an HEV structural protein showed prion-like properties. The prion domain (PrD) of yeast prion Sup35 could be functionally replaced by HEV-ORF3 and its candidate PrD (cPrD). A single amino acid substitution in the cPrD reduced the aggregation propensity of ORF3 and blocked the function of ORF3 in enhancing the stability of microtubules in HEV-infected cells, thus blocking virion release from the infected cells and resulting in reduced HEV pathogenicity in Mongolian gerbils. These data suggest that HEV-ORF3 is a novel functional prion-like protein which assembles into a filamentous structure for virion release, supporting the hypothesis that the self-propagating properties of prion proteins are widely exploited as epigenetic information carriers in nature.

microbiology↗

HCP5 prevents ubiquitination-mediated UTP3 degradation to inhibit apoptosis by activating c-Myc transcriptional activity

Inducing cancer cell apoptosis through cytotoxic reagents is the main therapeutic strategy for diverse cancer types. However, several antiapoptotic factors impede curative cancer therapy by driving cancer cells to resist cytotoxic agent-induced apoptosis, thus leading to refractoriness and relapse. To define critical antiapoptotic factors that contribute to chemoresistance in esophageal squamous cell carcinoma (ESCC), we generated two pairs of parental and apoptosis-resistant cell models through cisplatin (DDP) induction and then performed whole-transcriptome sequencing. We identified the long noncoding RNA (lncRNA) histocompatibility leukocyte antigen complex P5 (HCP5) as the chief culprit for chemoresistance. Mechanistically, HCP5 interacts with UTP3 small subunit processome component (UTP3) and prevents UTP3 degradation from E3 ligase tripartite motif containing 29 (TRIM29)-mediated ubiquitination. UTP3 then recruits c-Myc to activate vesicle-associated membrane protein 3 (VAMP3) expression. Activated VAMP3 suppresses caspase-dependent apoptosis and eventually leads to chemoresistance. Accordingly, the expression level of the HCP5/UTP3/c-Myc/VAMP3 axis in chemoresistant patients is significantly higher than that in chemosensitive patients. Thus, our study demonstrated that the HCP5/UTP3/c-Myc/VAMP3 axis plays an important role in the inhibition of cancer cell apoptosis and that HCP5 can be a promising chemosensitive target for cancer treatment.

cancer biology↗

DLGAP1-AS2-Mediated Phosphatidic Acid Synthesis Confers Chemoresistance via Activation of YAP Signaling

Squamous cell carcinomas (SCCs) constitute a group of human malignancies that originate from the squamous epithelium. Most SCC patients experience treatment failure and relapse and have a poor prognosis due to de novo and acquired resistance to first-line chemotherapeutic agents. To identify chemoresistance mechanisms and explore novel chemosensitizer targets, we performed whole-transcriptome sequencing of paired resistant/parental SCC cells. We identified DLGAP1 antisense RNA 2 (D-AS2) as a crucial noncoding RNA that contributes to chemoresistance in SCC. Mechanistically, D-AS2 associates with histones to regulate the distal elements of FAM3 metabolism regulating signaling molecule D (FAM3D) and reduces extracellular FAM3D protein secretion. FAM3D interacts with Gi-coupled G protein-coupled receptor (GPCR) formyl peptide receptor (FPR) 1 and FPR2 to suppress phospholipase D (PLD) activity; thus, reduced FAM3D activates PLD signaling. Moreover, activated PLD promotes phosphatidic acid (PA) production and subsequent yes-associated protein (YAP) nuclear translocation. Accordingly, in vivo administration of a D-AS2-targeting antisense oligonucleotide sensitizes SCC to cisplatin treatment. In summary, our study reveals that D-AS2/FAM3D-mediated PLD/PA lipid signaling is essential in SCC chemoresistance and that D-AS2 can be targeted to sensitize SCC to cytotoxic chemotherapeutic agents. SignificanceThis study identifies D-AS2 as a targetable lipid-related lncRNA that activates YAP signaling via PLD/PA axis to trigger chemoresistance in SCC.

cancer biology↗

Combining Multi-Dimensional Molecular Fingerprints to Predict hERG Cardiotoxicity of Compounds

At present, drug toxicity has become a critical problem with heavy medical and economic burdens. acLQTS (acquired Long QT Syndrome) is acquired cardiac ion channel disease caused by drugs blocking the hERG channel. Therefore, it is necessary to avoid cardiotoxicity in the drug design and computer models have been widely used to fix this plight. In this study, we present a molecular fingerprint based on the molecular dynamic simulation and uses it combined with other molecular fingerprints (multi-dimensional molecular fingerprints) to predict hERG cardiotoxicity of compounds. 203 compounds with hERG inhibitory activity (pIC50) were retrieved from a previous study and predicting models were established using four machine learning algorithms based on the single and multi-dimensional molecular fingerprints. Results showed that MDFP has the potential to be an alternative to traditional molecular fingerprints and the combination of MDFP and traditional molecular fingerprints can achieve higher prediction accuracy. Meanwhile, the accuracy of the best model, which was generated by consensus of four algorithms with multi-dimensional molecular fingerprints, was 0.694 (RMSE) in the test dataset. Besides, the number of hydrogen bonds from MDFP has been determined as a critical factor in the predicting models, followed by rgyr and sasa. Our findings provide a new sight of MDFP and multi-dimensional molecular fingerprints in building models of hERG cardiotoxicity prediction.

pharmacology and toxicology↗