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Biology subjects

Shin, H. J.

Publications and source records attributed to Shin, H. J..

10 recordsLinked to original sources

RIG-I-MAVS-NOXA axis coordinates antiviral defense and apoptosis during parahenipavirus infection

The Gamak virus (GAKV) is a recently identified shrew-borne paramyxovirus belonging to the genus Parahenipavirus, which also includes the zoonotic Langya virus (LayV). Despite the growing recognition of shrew-associated paramyxoviruses, the host pathways that detect infection and regulate antiviral responses remain poorly understood. In this study, we characterized host responses to GAKV infection using integrated in vitro and in vivo approaches. GAKV infection induced robust innate immune responses in A549 cells, characterized by activation of interferon regulatory factor 3 (IRF3) and signal transducer and activator of transcription 1 (STAT1), together with induction of type I interferon (IFN) and interferon-stimulated genes (ISGs). Transcriptomic analysis further revealed coordinated enrichment of antiviral and intrinsic apoptosis-associated pathways, suggesting a link between innate immune signaling and apoptosis during GAKV infection. Genetic analyses identified retinoic acid-inducible gene I (RIG-I) and mitochondrial antiviral signaling protein (MAVS) as essential mediators of antiviral signaling and apoptosis during GAKV infection. Furthermore, disruption of type I IFN-STAT1 signaling attenuated apoptosis. NOXA knockdown reduced apoptosis and enhanced viral replication, identifying NOXA as a downstream effector linking innate immune activation to apoptosis. Consistent with these in vitro findings, intranasal GAKV infection in six-week-old female wild-type BALB/c mice was associated with lung-restricted viral RNA detection and induction of antiviral responses without overt disease. Together, these findings identify a RIG-I-MAVS-IFN-NOXA signaling axis that integrates antiviral and apoptotic responses during GAKV infection, providing a mechanistic framework for understanding host defense against parahenipaviruses.

microbiology↗

Proteomic Profiling Identifies CLDN3 as a Tumor-Selective Therapeutic Target in Small Cell Lung Cancer

Small cell lung cancer (SCLC) remains a highly lethal disease with limited targetable surface antigens beyond delta-like ligand 3 (DLL3). We sought to systematically identify and validate tumor-selective cell-surface targets in relapsed SCLC. To this end, we developed an integrated proteogenomic pipeline combining single-cell RNA sequencing, combinatorial optimization, mass spectrometry-based proteomics, and immunohistochemistry to systematically map the SCLC surfaceome of 49 tumors across 25 patients with relapsed SCLC. Using this approach we found claudin-3 (CLDN3) to be a consistently expressed and tumor-selective antigen, with broader coverage than DLL3, which is the current clinical benchmark. CLDN3 was highly expressed across various treatment states, while maintaining low expression in most nonmalignant tissues. Functional validation using a novel CLDN3-specific monoclonal antibody (ABN501) demonstrated NK cell-mediated cytotoxicity in vitro and tumor regression in vivo, as well as a favorable safety profile. These findings support clinical development of CLDN3-directed therapies and demonstrate the utility of integrated proteogenomic approaches for antigen discovery in solid tumors.

cancer biology↗

Genome-wide CRISPR screens identify PTGES3 as a novel AR modulator

The androgen receptor (AR) is a critical driver of prostate cancer (PCa). To study regulators of AR protein levels and oncogenic activity, we created the first live cell quantitative endogenous AR fluorescent reporters. Leveraging this novel AR reporter, we performed genome-scale CRISPRi flow cytometry sorting screens to systematically identify genes that modulate AR protein levels. We identified and validated known AR protein regulators including HOXB13 and GATA2 and also unexpected top hits including PTGES3, a poorly characterized gene in PCa. PTGES3 repression resulted in loss of AR protein, cell cycle arrest, and cell death in AR-driven PCa models. PTGES3 is not a commonly essential gene, and our data nominate it as a prime PCa therapeutic target. Clinically, analysis of PCa data demonstrate that PTGES3 expression is associated with AR-directed therapy resistance. Mechanistically, we show PTGES3 binds directly to AR, forms a protein complex with AR in the nucleus, regulates AR protein stability in vitro and in vivo and modulates AR function in the nucleus at AR target genes. PTGES3 represents a novel therapeutic target for overcoming known mechanisms of resistance to existing AR-directed therapies in PCa.

cancer biology↗

Identification and Characterization of PLUTO-201, a Novel Long Non-Coding RNA Associated with Poor Outcomes in Prostate Cancer

Background: Despite extensive investigation, the factors promoting aggressive prostate cancer are poorly understood. In particular, despite a few prominent examples, the role of long non-coding RNAs (lncRNAs) is largely unknown. Methods: We performed a comprehensive analysis of whole-genome transcriptome data to identify differential expression across 1,567 patients with prostate cancer, then correlated differential expression with risk of metastatic recurrence. We characterized the lncRNA most associated with metastasis in vitro and in vivo to investigate the mechanism by which it promotes aggressive prostate cancer. Results: We have identified a novel lncRNA, Prostate Cancer Associated hnRNPK Interacting Transcript (PCAHIT), which is strongly associated with metastasis and poor overall survival in men with prostate cancer. We find that overexpression/knockdown of PCAHIT in pre-clinical models of prostate cancer modulates proliferation rates and markers of an aggressive phenotype through regulation of steroid biosynthesis and expression of the MHC class I complex, driving increased growth in androgen-depleted conditions and decreased susceptibility to T cell-mediated cytotoxicity. We further find that the heterogeneous nuclear ribonucleoprotein hnRNPK directly binds PCAHIT and is indispensable for its activity. Conclusions: Overall, our findings indicate that PCAHIT is a driver of aggressive prostate cancer phenotypes and poor clinical outcomes through suppression of the immune response and increased androgen-independent cancer growth. PCAHIT is a potential biomarker of aggressive disease.

cancer biology↗

Epidermal Growth Factor Receptor Regulates Beclin-1 in Hyperoxia

While delivery of supplemental oxygen is a life-saving therapy, exposure to high levels of oxygen, called hyperoxia, is associated with increased mortality in the intensive care unit (ICU). Hyperoxia leads to oxidant-mediated acute lung injury (ALI) and pulmonary cell death, called hyperoxic acute lung injury (HALI). Elucidation of molecular mechanisms in HALI could identify therapeutic targets in ALI. In the current study, we examined in vivo effects of HALI on Beclin-1 (BCN1), a molecule that regulates autophagy and cell death. Effects of HALI on BCN1 and autophagy markers were examined in wildtype mice. Analysis of BCN1 and autophagy was completed via Western blot, RT-qPCR, and immunohistochemistry. In wildtype mice, HALI led to increased BCN1 in the lung and in the alveolar epithelium. HALI resulted in significant alterations in markers of autophagy in the lung, including reduced microtubule-associated protein 1B-light chain (LC3B)-II/-I ratios, suggesting reduced autophagic flux. HALI caused increased LDH release in human alveolar type-II cells derived from induced pluripotent stem cells (AT2siPSC), as well as reduced LC3B-II/-I ratios. We previously showed that inhibition of the tyrosine kinase receptor epidermal growth factor receptor (EGFR) is protective in HALI. EGFRWa5/+ mice, which have genetically reduced EGFR activity and improved survival in HALI, showed increased total BCN1, reduced phosphorylated-(p-)/total BCN1 ratios, and decreased LC3B-II/-I ratios in the lung in HALI compared with wildtype. Administration of wortmannin, a phosphatidylinositol-3 kinase (PI3K) inhibitor which decreases BCN1-mediated autophagy, led to increased mortality in HALI in wildtype mice. These data support that regulation of BCN1 and autophagy by EGFR is a protective mechanism in HALI, a pathway which warrants further study for its therapeutic potential. KEY MESSAGESHALI is associated with increased mortality in the ICU and causes alveolar epithelial cell death, but the role of BCN1 in HALI is not well defined. This study shows that BCN1, a molecule involved in autophagy and cell death, is regulated by EGFR in HALI in vivo. These results are significant because regulation by BCN1 and autophagy by EGFR is a novel pathway in HALI with therapeutic potential that warrants further study.

cell biology↗

Oligomeric HIV-1 Integrase Structures Reveal Functional Plasticity for Intasome Assembly and RNA Binding

Integrase (IN) performs dual essential roles during HIV-1 replication. During ingress, IN functions within an oligomeric "intasome" assembly to catalyze viral DNA integration into host chromatin. During late stages of infection, tetrameric IN binds viral RNA and orchestrates the condensation of ribonucleoprotein complexes into the capsid core. The molecular architectures of HIV-1 IN assemblies that mediate these distinct events remain unknown. Furthermore, the tetramer is an important antiviral target for allosteric IN inhibitors. Here, we determined cryo-EM structures of wildtype HIV-1 IN tetramers and intasome hexadecamers. Our structures unveil a remarkable plasticity that leverages IN C-terminal domains and abutting linkers to assemble functionally distinct oligomeric forms. Alteration of a newly recognized conserved interface revealed that both IN functions track with tetramerization in vitro and during HIV-1 infection. Collectively, our findings reveal how IN plasticity orchestrates its diverse molecular functions, suggest a working model for IN-viral RNA binding, and provide atomic blueprints for allosteric IN inhibitor development.

biochemistry↗

In vitro broad-spectrum antiviral activity of MIT-001, a mitochondria-targeted reactive oxygen species scavenger, against severe acute respiratory syndrome coronavirus 2 and multiple zoonotic viruses

The COVID-19 pandemic caused by SARS-CoV-2 becomes a serious threat to global health and requires the development of effective antiviral therapies. Current therapies that target viral proteins have limited efficacy with side effects. In this study, we investigated the antiviral activity of MIT-001, a small molecule reactive oxygen species (ROS) scavenger targeting mitochondria, against SARS-CoV-2 and other zoonotic viruses in vitro. The antiviral activity of MIT-001 was quantified by RT-qPCR and plaque assay. We also evaluated the functional analysis of MIT-001 by JC-1 staining to measure mitochondrial depolarization, total RNA sequencing to investigate gene expression changes, and immunoblot to quantify protein expression levels. The results showed that MIT-001 effectively inhibited the replication of B.1.617.2 and BA.1 strains, Zika virus, Seoul virus, and Vaccinia virus. Treatment with MIT-001 restored the expression of heme oxygenase-1 (HMOX1) and NAD(P)H: quinone oxidoreductase 1 (NqO1) genes, anti-oxidant enzymes reduced by SARS-CoV-2, to normal levels. The presence of MIT-001 also alleviated mitochondrial depolarization caused by SARS-CoV-2 infection. These findings highlight the potential of MIT-001 as a broad-spectrum antiviral compound that targets for zoonotic RNA and DNA viruses, providing a promising therapeutic approach to combat viral infection.

microbiology↗

Ocular tropism of SARS-CoV-2 with retinal inflammation through neuronal invasion in animal models

Although ocular manifestations are commonly reported in patients with coronavirus disease 2019 (COVID-19), there is currently no consensus on ocular tropism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To investigate this, we infected K18-hACE2 mice with SARS-CoV-2 using various routes. We observed ocular manifestation and retinal inflammation with cytokine production in the eyes of intranasally (IN) infected mice. An intratracheal (IT) injection resulted in virus spread from the lungs to the brain and eyes via trigeminal and optic nerves. Ocular and neuronal invasion were confirmed by an intracerebral (IC) infection. Notably, eye-dropped (ED) virus did not infect the lungs and was undetectable with time. Using infectious SARS-CoV-2-mCherry clones, we demonstrated the ocular and neurotropic distribution of the virus in vivo by a fluorescence-imaging system. Evidence for the ocular tropic and neuroinvasive characteristics of SARS-CoV-2 was confirmed in wild-type Syrian hamsters. Our data provides further understanding of the viral transmission; SARS-CoV-2 clinical characteristics; and COVID-19 control procedures. SummarySARS-CoV-2 can spread from the respiratory tract to the brain and eyes via trigeminal and optic nerves in animal models. This ocular tropism of SARS-CoV-2 through neuronal invasion likely causes ocular manifestation and retinal inflammation. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=148 SRC="FIGDIR/small/488607v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@151c2d5org.highwire.dtl.DTLVardef@ce3aeforg.highwire.dtl.DTLVardef@17f453aorg.highwire.dtl.DTLVardef@99e9c2_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Chitinase 3-like-1 is a Therapeutic Target That Mediates the Effects of Aging in COVID-19

COVID-19 is caused by the SARS-CoV-2 (SC2) virus and is more prevalent and severe in the elderly and patients with comorbid diseases (CM). Because chitinase 3-like-1 (CHI3L1) is induced during aging and CM, the relationships between CHI3L1 and SC2 were investigated. Here we demonstrate that CHI3L1 is a potent stimulator of the SC2 receptor ACE2 and viral spike protein priming proteases (SPP), that ACE2 and SPP are induced during aging and that anti-CHI3L1, kasugamycin and inhibitors of phosphorylation, abrogate these ACE2- and SPP-inductive events. Human studies also demonstrated that the levels of circulating CHI3L1 are increased in the elderly and patients with CM where they correlate with COVID-19 severity. These studies demonstrate that CHI3L1 is a potent stimulator of ACE2 and SPP; that this induction is a major mechanism contributing to the effects of aging during SC2 infection and that CHI3L1 coopts the CHI3L1 axis to augment SC2 infection. CHI3L1 plays a critical role in the pathogenesis of and is an attractive therapeutic target in COVID-19.

immunology↗

Novel surface plasmon resonance biosensor that uses full-length Det7 phage tail protein for rapid and selective detection of Salmonella enterica serovar Typhimurium

We report a novel surface plasmon resonance (SPR) biosensor that uses the full-length Det7 phage tail protein (Det7T) to rapidly and selectively detect Salmonella enterica serovar Typhimurium. Det7T, which was obtained using recombinant protein expression and purification in Escherichia coli, demonstrated a size of [~]75 kDa upon SDS-PAGE and was homotrimeric in its native structure. Micro-agglutination and TEM data revealed that the protein specifically bound to the host, S. Typhimurium, but not to non-host E. coli K-12 cells. The observed protein agglutination occurred over a concentration range of 1.5[~]25 g.ml-1. The Det7T proteins were immobilized on gold-coated surfaces using amine-coupling to generate a novel Det7T-functionalized SPR biosensor, wherein the specific binding of these proteins with bacteria was detected by SPR. We observed rapid detection of ([~] 20 min) and typical binding kinetics with S. Typhimurium in the range of 5 x 104-5 x 107 CFU.ml-1, but not with E. coli at any tested concentration, indicating that the sensor exhibited recognition specificity. Similar binding was observed with 10% apple juice spiked with S. Typhimurium, suggesting that this strategy could be expanded for the rapid and selective monitoring of target microorganisms in the environment.

bioengineering↗