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Hu, J.

Publications and source records attributed to Hu, J..

At least 325 records · Page 18Linked to original sources

TERT accelerates BRAF mutant-induced thyroid cancer dedifferentiation and progression by regulating ribosome biogenesis

TERT reactivation occurs frequently in human malignancies. While BRAF activating mutation widely existed in cancers at various stages, TERT reactivation mainly occurs in advanced tumors. However, in vivo evidence for TERT role in cancer progression and the underlying mechanism is currently lacking. In this study, we induced TERT and/or BRAF V600E expression in mouse thyroid epithelium. TERT overexpression alone had no evident effect on tumor initiation. BRAFVE expression itself induced mediocre papillary thyroid cancer (PTC). Notably, the co-expression of BRAFVE and TERT resulted in aggressive poorly differentiated thyroid carcinoma (PDTC). Spatial transcriptome revealed that tumors from co-mutant mice were highly heterogeneous and dedifferentiation process significantly correlated with ribosomal pathways. Mechanistically, TERT boosted ribosomal RNA expression and protein synthesis. CX-5461, a rRNA transcription inhibitor, effectively blocked proliferation and induced redifferentiation. Thus, TERT promotes thyroid cancer progression by inducing dedifferentiation, and ribosome biogenesis inhibition represents a potential treatment strategy for TERT-reactivated cancers. Highlights[tpltrtarr] TERT accelerated thyroid cancer dedifferentiation and metastasis in vivo [tpltrtarr]TERT regulated rRNA metabolism and MTORC1/ S6K/RPS6 activities [tpltrtarr]CX-5461 inhibited the progression of TERT-reactivated melanoma and thyroid cancer [tpltrtarr]Inhibition of rRNA induced redifferentiation of advanced thyroid cancer with TERT activation

cancer biology↗

Loss of WNT5 Proteins Reprograms Neutrophils in the Spleen to Provide Protection for DSS-Induced Colitis

WNT5A and WNT5B are two close homologs, both of which are implicated in the pathogenesis of inflammatory bowel diseases. However, the roles these two proteins play in the disease remain largely uncharacterized. Here, we report that double knockout of Wnt5a and Wnt5b (Wnt5 DKO) protects mice from Dextran Sodium Sulfate (DSS)-induced colitis in mice, accompanied with greater splenomegaly, stronger expansion of peripheral myeloid cells, and less colonic CD8+ T cell granzyme B expression than those of the control mice. Depletion of neutrophils or splenectomy abrogates the phenotypic differences between Wnt5 DKO and control mice largely by exacerbating colitis phenotypes and increasing colonic CD8+ T cell GZMB expression in the Wnt5 DKO mice. In addition, neutrophils from the Wnt5 DKO colitic mice exert stronger suppression of CD8+ T cells than those from the control mice in culture. Single-cell RNA sequencing and proteomic analyses indicate that neutrophils from DSS-treated Wnt5 DKO mice are of hyper-immunosuppressive and hypo-inflammatory characteristics and are distinct from those of DSS-treated control mice as well as myeloid-derived suppressor cells in tumor-bearing mice. Thus, our study reveals that the lack of WNT5 reprograms neutrophils in spleens to limit colonic injury during DSS-induced colitis.

immunology↗

Efficient estimation of breakpoints in piecewise-linear mixed-effects models for longitudinal ophthalmic studies

PurposeBroken stick analysis is a widely used approach for detecting unknown breakpoints where association between measurements is non-linear. We propose LIMBARE, an advanced linear mixed-effects breakpoint analysis with robust estimation, especially designed for longitudinal ophthalmic studies. LIMBARE accommodates repeated measurements from both eyes and overtime, and effectively address the presence of outliers. MethodsThe model setup of LIMBARE and computing algorithm for point and confidence interval estimates of the breakpoint was introduced. The performance of LIMBARE and other competing methods was assessed via comprehensive simulation studies and application to a longitudinal ophthalmic study with 216 eyes (145 subjects) followed for an average of 3.7{+/-}1.3 years to examine the longitudinal association between structural and functional measurements. ResultsIn simulation studies, LIMBARE showed the smallest bias and mean squared error (MSE) for estimating the breakpoint, with empirical coverage probability of corresponding CI estimate closest to the nominal level for scenarios with and without outlier data points. In the application to the longitudinal ophthalmic study, LIMBARE detected two breakpoints between visual field mean deviation (MD) and retinal nerve fiber layer thickness (RNFL) and one breakpoint between MD and cup to disc ratio (CDR), while the cross-sectional analysis approach only detected one and none, respectively. ConclusionsLIMBARE enhances breakpoint estimation accuracy in longitudinal ophthalmic studies, while cross-sectional analysis approach is not recommended for future studies. Translational RelevanceOur proposed method and companion software R package provides a valuable computational tool for advancing longitudinal ophthalmology research and exploring the association relationships between ophthalmic variables.

bioinformatics↗

An efficient context-aware approach for whole slide image classification

Computational pathology for gigapixel whole slide images (WSIs) at slide-level is helpful in disease diagnosis and remains challenging. We propose a context-aware approach termed WSI Inspection via Transformer (WIT) for slide-level classification via holistically modeling dependencies among patches on the WSI. WIT automatically learns feature representation of WSI by aggregating features of all image patches. We evaluate classification performance of WIT along with state-of-the-art baseline method. WIT achieved an accuracy of 82.1% (95% CI, 80.7% - 83.3%) in the detection of 32 cancer types on the TCGA dataset, 0.918 (0.910 - 0.925) in diagnosis of cancer on the CPTAC dataset and 0.882 (0.87 - 0.890) in the diagnosis of prostate cancer from needle biopsy slide, outperforming the baseline by 31.6%, 5.4% and 9.3%, respectively. WIT can pinpoint the WSI regions that are most influential for its decision. WIT represents a new paradigm for computational pathology, facilitating the development of effective tools for digital pathology.

pathology↗

Profiling the bloodstream form and procyclic form Trypanosoma brucei cell cycle using single cell transcriptomics

African trypanosomes proliferate as bloodstream forms and procyclic forms in the mammal and tsetse fly midgut, respectively. This allows them to colonise the host environment upon infection and ensure life cycle progression. Yet, understanding of the mechanisms that regulate and drive the cell replication cycle of these forms is limited. Using single cell transcriptomics on unsynchronised cell populations, we have obtained high resolution cell cycle regulated transcriptomes of both procyclic and slender bloodstream form Trypanosoma brucei without prior cell sorting or synchronisation. Additionally, we describe an efficient freeze-thawing protocol that allows single cell transcriptomic analysis of cryopreserved T. brucei. Computational reconstruction of the cell cycle using periodic pseudotime inference allowed the dynamic expression patterns of cycling genes to be profiled for both life cycle forms. Comparative analyses identify a core cycling transcriptome highly conserved between forms, as well as several genes where transcript levels dynamics are form-specific. Comparing transcript expression patterns with protein abundance revealed that the majority of genes with periodic cycling transcript and protein levels exhibit a relative delay between peak transcript and protein expression. This work reveals novel detail of the cell cycle regulated transcriptomes of both forms, which are available for further interrogation via an interactive webtool.

microbiology↗

Reimagining Gene-Environment Interaction Analysis for Human Complex Traits

In this study, we introduce PIGEON--a novel statistical framework for quantifying and estimating polygenic gene-environment interaction (GxE) using a variance component analytical approach. Based on PIGEON, we outline the main objectives in GxE studies, demonstrate the flaws in existing GxE approaches, and introduce an innovative estimation procedure which only requires summary statistics as input. We demonstrate the statistical superiority of PIGEON through extensive theoretical and empirical analyses and showcase its performance in multiple analytic settings, including a quasi-experimental GxE study of health outcomes, gene-by-sex interaction for 530 traits, and gene-by-treatment interaction in a randomized clinical trial. Our results show that PIGEON provides an innovative solution to many long-standing challenges in GxE inference and may fundamentally reshape analytical strategies in future GxE studies.

genetics↗

Fluorescein-based sensors to purify human α-cells for functional and transcriptomic analyses

Pancreatic -cells secrete glucagon, an insulin counter-regulatory peptide hormone critical for the maintenance of glucose homeostasis. Investigation of the function of human -cells remains a challenge due to the lack of cost-effective purification methods to isolate high-quality -cells from islets. Here, we use the reaction-based probe diacetylated Zinpyr1 (DA-ZP1) to introduce a novel and simple method for enriching live -cells from dissociated human islet cells with > 97% purity. The -cells, confirmed by sorting and immunostaining for glucagon, were cultured up to 10 days to form -pseudoislets. The -pseudoislets could be maintained in culture without significant loss of viability, and responded to glucose challenge by secreting appropriate levels of glucagon. RNA-sequencing analyses (RNA-seq) revealed that expression levels of key -cell identity genes were sustained in culture while some of the genes such as DLK1, GSN, SMIM24 were altered in -pseudoislets in a time-dependent manner. In conclusion, we report a method to sort human primary -cells with high purity that can be used for downstream analyses such as functional and transcriptional studies.

cell biology↗

PTHrP buffers Wnt/Beta-catenin activity through a negative feedback loop to maintain articular cartilage homeostasis

Osteoarthritis (OA) is the most common joint disease worldwide and a leading cause of disability. The Wnt/{beta}-catenin cascade is essential in articular cartilage development and homeostasis. It has proved that both overexpression and loss of {beta}-catenin lead to cartilage degeneration and OA symptoms. However, the mechanism of Wnt/{beta}-catenin balance in healthy cartilage remains unclear. In the present work, we confirmed that the Wnt/{beta}-catenin activation and PTHrP suppression in cartilage during the post-traumatic OA process. Then, we demonstrated that Wnt/{beta}-catenin upregulated PTHrP expression through binding to its promoter (P2), and induce mRNA (AT6) transcript expression, while PTHrP repressed Wnt/{beta}-catenin activity, and formed a Wnt/{beta}-catenin-PTHrP negative feedback loop in the very primary chondrocytes to maintain cartilage homeostasis. However, this negative feedback loop vanished in dedifferentiated chondrocytes, hypertrophic chondrocytes, and IL-1{beta} treated very primary chondrocytes. We further found that miR-106b-5p was increased in these "aberrant" chondrocytes and directly targeted PTHrP mRNA to abolish the feedback loop. PKC-{zeta} was activated by PTHrP through phosphorylation at Thr410/403, and subsequently induced {beta}-catenin phosphorylation and ubiquitination. Finally, we disclosed that exogenous PTHrP attenuated OA progression exogenous PTHrP attenuated OA progression. Together, these findings reveal that PTHrP is a vital mediator to keep Wnt/{beta}-catenin activity homeostasis in healthy cartilage through a negative feedback loop, and PTHrP might be a therapeutic target for OA and cartilage regeneration.

pathology↗

Multi-site assessment of reproducibility in high-content live cell imaging data

High-content image-based cell phenotyping provides fundamental insights in a broad variety of life science areas. Striving for accurate conclusions and meaningful impact demands high reproducibility standards, even more importantly with the advent of data sharing initiatives. However, the sources and degree of biological and technical variability, and thus the reproducibility and usefulness of meta-analysis of results from live-cell microscopy have not been systematically investigated. Here, using high content data describing features of cell migration and morphology, we determine the sources of variability across different scales, including between laboratories, persons, experiments, technical repeats, cells and time points. Significant technical variability occurred between laboratories, providing low value to direct meta-analysis on the data from different laboratories. However, batch effect removal markedly improved the possibility to combine image-based datasets of perturbation experiments. Thus, reproducible quantitative high-content cell image data and meta-analysis depend on standardized procedures and batch correction applied to studies of perturbation effects.

cell biology↗

Irreversible inactivation of lactate racemase by sodium borohydride reveals reactivity of the nickel-pincer nucleotide cofactor

The nickel-pincer nucleotide (NPN) cofactor discovered in lactate racemase from Lactiplantibacillus plantarum (LarALp) is essential for the activities of racemases/epimerases in the highly diverse LarA superfamily. Prior mechanistic studies have established a proton-coupled hydride-transfer mechanism for LarALp, but direct evidence showing that hydride attacks the C4 atom in the pyridinium ring of NPN has been lacking. Here, we show that sodium borohydride (NaBH4) irreversibly inactivates LarALp accompanied by a rapid color change of the enzyme. The drastically altered ultraviolet-visible spectra during NaBH4 titration supported hydride transfer to C4 of NPN, and the concomitant Ni loss unraveled by mass spectrometry experiments accounted for the mechanism-based inactivation. High resolution structures of LarALp revealed a substantially weakened C-Ni bond in the metastable sulfite-NPN adduct where the NPN cofactor is in the reduced state. These findings allowed us to propose a mechanism of LarALp inactivation by NaBH4 that provides key insights into the enzyme-catalyzed reaction and sheds light on the reactivity of small molecule NPN mimetics.

biochemistry↗

Integrated Network Pharmacology and Experimental Analysis Unveil Modulation of EGFR/MAPK Signaling Cascades in Acute Cerebral Ischemia-Reperfusion Injury by Qing-Tong-Hua-Yu Decoction

ObjectiveBased on network pharmacology, the response of Qing-tong-hua-yu Decoction (QTHY) to the regulation of EGFR/MAPK signaling cascade in cerebral ischemia-reperfusion injury was discussed and the possible mechanism of the protective effect of QTHY on the cerebral ischemia-reperfusion injury was studied. MethodsA compound-target disease-function-pathway network was established and analyzed based on the network pharmacology approach used in Chinese medicine. The correlation, which is between effect of the components of QTHY Decoction against CI/RI with EGFR/MAPK signalling cascade response, was observed. And then the degree of neurological deficits in each group was assessed after cerebral ischemia for 2 hours and reperfusion for 3 hours, 24 hours, 3 days and 7 days. Expression levels of EGFR and p44/42MAPK in ischemic brain tissue at different time points in various groups of rats were tested by Western bolt (WB), real-time quantitative PCR (RT-qPCR) and immunohistochemistry (IHC). ResultsNetwork pharmacology analysis revealed that QTHY-mediated treatment involved 439 key targets, in which the effect of QTHY groups against CI/RI was associated with EGFR/MAPK signaling cascade. QTHY treatment reduced neurological deficit scores and improved ischemic changes in rats. In addition, QTHY promoted EGFR and p44/42MAPK expression in the SVZ through the EGFR/MAPK signaling cascade, with varying degrees of improvement at different time points. ConclusionQTHY can better improve cerebral ischemia injury in CI / RI rats and exert the neuroprotective effect of cerebral ischemia-reperfusion injury. This may be related to the potential of QTHY to activate the EGFR / MAPK signaling cascade, which is consistent with the results of network pharmacology analysis.

neuroscience↗

Deciphering tumor ecosystems at super-resolution from spatial transcriptomics with TESLA

Recent advances in spatial transcriptomics (ST) have enabled the comprehensive characterization of gene expression in tumor microenvironment. However, ST only measures expression in discrete spots, which limits their usefulness in studying the detailed structure of TME. Here we present TESLA, a machine learning framework for multi-level tissue annotation in ST. TESLA integrates histological information with gene expression to annotate heterogeneous immune and tumor cells directly on the histology image, and further detects tertiary lymphoid structures and differential transcriptome programs between the edge and core of a tumor. TESLA provides a powerful tool for understanding the spatial architecture of the TME.

bioinformatics↗

Evaluation of antibody kinetics and durability in health subjects vaccinated with inactivated COVID-19 vaccine (CoronaVac): A cross-sectional and cohort study in Zhejiang, China

BackgroundAlthough inactivated COVID-19 vaccines are proven to be safe and effective in the general population, the dynamic response and duration of antibodies after vaccination in the real world should be further assessed. MethodsWe enrolled 1067 volunteers who had been vaccinated with one or two doses of CoronaVac in Zhejiang Province, China. Another 90 healthy adults without previous vaccinations were recruited and vaccinated with three doses of CoronaVac, 28 days and 6 months apart. Serum samples were collected from multiple timepoints and analyzed for specific IgM/IgG and neutralizing antibodies (NAbs) for immunogenicity evaluation. Antibody responses to the Delta and Omicron variants were measured by pseudovirus-based neutralization tests. ResultsOur results revealed that binding antibody IgM peaked 14-28 days after one dose of CoronaVac, while IgG and NAbs peaked approximately 1 month after the second dose then declined slightly over time. Antibody responses had waned by month 6 after vaccination and became undetectable in the majority of individuals at 12 months. Levels of NAbs to live SARS-CoV-2 were correlated with anti-SARS-CoV-2 IgG and NAbs to pseudovirus, but not IgM. Homologous booster around 6 months after primary vaccination activated anamnestic immunity and raised NAbs 25.5-fold. The NAb inhibition rate subsequently rose to 36.0% for Delta (p=0.03) and 4.3% for Omicron (p=0.004), and the response rate for Omicron rose from 7.9% (7/89) to 17.8% (16/90). ConclusionsTwo doses of CoronaVac vaccine resulted in limited protection over a short duration. The homologous booster slightly increased antibody responses to the Delta and Omicron variants; therefore, the optimization of booster procedures is vital. FundingKey Research and Development Program of Zhejiang Province; Key Program of Health Commission of Zhejiang Province/ Science Foundation of National Health Commission; Major Program of Zhejiang Municipal Natural Science Foundation.

immunology↗

Regulation of adventitial interstitial fluid circulation by heartbeat and respiration

Converging studies showed interstitial fluid (ISF) adjacent to blood vessels flows along adventitia of vasculature into heart and lungs. We aim to reveal circulatory pathways and regulatory mechanism of such adventitial ISF flow in rat model. By MRI, real-time fluorescent imaging, micro-CT and histological analysis, ISF was found to flow in adventitial matrix surrounded by fascia and along systemic vessels into heart, then flow into lungs via pulmonary arteries and back to heart via pulmonary veins, which was neither perivascular tissues nor blood or lymphatic vessels. Under physiological conditions, speckle-like adventitial ISF flow rate was positively correlated with heart rate, increased when holding breath, became pulsative during heavy breathing. During cardiac or respiratory cycle, each dilation or contraction of heart or lungs can generate to-and-fro adventitial ISF flow along femoral veins. Discovered regulatory mechanisms of adventitial ISF flow along vasculature by heart and lungs will revolutionize understanding of cardiovascular system. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=159 SRC="FIGDIR/small/512678v3_ufig1.gif" ALT="Figure 1"> View larger version (68K): org.highwire.dtl.DTLVardef@1d29c16org.highwire.dtl.DTLVardef@583f5org.highwire.dtl.DTLVardef@1a551eorg.highwire.dtl.DTLVardef@ca4780_HPS_FORMAT_FIGEXP M_FIG Graphic abstract of adventitial interstitial fluid cycle by heartbeat and respiration.The heart and lungs can work together to regulate the ISF (green arrow) adjacent to blood vessels to flow centripetally in an adventitial pathway along the major arteries and veins of the systemic vasculature to the epicardium and myocardium, then flow into the lungs via the pulmonary arteries and back to the heart via the pulmonary veins, forming an adventitial ISF circulatory network. Under physiological conditions, the speckle-like adventitial ISF flow rate was positively correlated with heart rate, increased when holding breath, and became pulsative during heavy breathing. During respiratory cycle, each expansion of the lungs during inflation generates a centrifugal flow of adventitial ISF along the systemic veins, while each contraction of the lungs during deflation generates a centripetal adventitial ISF flow. During cardiac cycle, each dilation of atria or ventricles generates a centripetal flow of adventitial ISF along the systemic veins, while each contraction of atria or ventricles generates a centrifugal adventitial ISF flow. C_FIG

physiology↗

Development of an affinity-enhanced clinical candidate TCR targeting NY-ESO-1 with optimal potency and high specificity

The clinical success of T-cell receptor (TCR)-based immunotherapy depends on the efficacy and specificity of TCRs. Naturally occurring TCRs have limited anti-tumor potency due to their low affinity for tumor antigens. Affinity enhancement is a promising strategy to generate highly potent TCRs. However, it is concerned that affinity-enhanced TCRs are prone to lose specificity. We isolated low affinity TCRs specific for NY-ESO-1157-165/HLA-A*02:01 from peripheral blood mononuclear cells of healthy donors. An affinity-enhanced TCR candidate with optimal affinity and specificity was generated using phage display and an extensive set of in vitro and in vivo assays. Alanine scanning mutagenesis showed that the TCR candidate retained specificity by making extensive contacts to the side chains of NY-ESO-1157-165 peptide. Adoptive transfer of T cells engineered with this candidate (termed TAEST16001) significantly inhibited tumor growth in subcutaneous, metastatic, and patient-derived xenograft (PDX) mouse tumor models. This study demonstrates that sophisticated engineering and screening techniques can be utilized to generate a clinical candidate TCR with potent anti-tumor activity without losing specificity. TAEST16001 was approved by the Center for Drug Evaluation (CDE) as the first TCR-based immunotherapy clinical trial in China (ClinicalTrials.gov Identifier: NCT03159585).

immunology↗

MAP4Ks inhibition promotes retinal neuron regeneration from Muumlller glia in adult mice

Mammalian Muller glia (MG) possess limited regenerative capacities. However, the intrinsic capacity of mammalian MG to transdifferentiate to generate mature neurons without transgenic manipulations remains speculative. Here we show that MAP4K4, MAP4K6 and MAP4K7, which are conserved Misshapen subfamily of ste20 kinases homologs, repress YAP activity in mammalian MG and therefore restrict their ability to be reprogrammed. However, by treating with a small molecule inhibitor of MAP4K4/6/7, mouse MG regain their ability to proliferate and enter into a retinal progenitor cell (RPC)-like state after NMDA-induced retinal damage; such plasticity was lost in YAP knockout MG. Moreover, spontaneous trans-differentiation of MG into retinal neurons expressing both amacrine and retinal ganglion cell (RGC) markers occurs after inhibitor withdrawal. Taken together, these findings suggest that MAP4Ks block the reprogramming capacity of MG in a YAP-dependent manner in adult mammals, which provides a novel avenue for the pharmaceutical induction of retinal regeneration in vivo.

neuroscience↗

Efficient Multi-Label Attribute Classification and Recognition of Microbiological Bacteria Based on Deep Learning and model fine-tuning

Bacterial vaginosis (BV) is the most common gynecological complaint affecting health of a large percentage of women worldwide. Traditional manual microscopy methods are expensive and time-consuming, to improve accuracy and efficiency, automated bacterial identification devices with detection intelligence algorithms are urgently needed. We propose a Fine-tuned SmallerVGG (FTS-VGG) deep convolutional network model based multi-label classification method for bacteria. Comparison experiments were deployed on several advanced backbone networks, including transfer learning on pre-trained VGG19, demonstrating that the proposed method achieves the advantages of being lighter, faster, more accurate and more efficient. Due to the high cost of time and expertise of experienced clinicians, we use random erasing for data augmentation to address the challenge of dataset collection and annotation, experiments demonstrate its robustness to occlusion. The proposed method has theoretical and practical implications, as well as the potential to be widely extended to other microscopic imaging applications.

biochemistry↗

Genome-scale mRNA transcriptomic insights into the mature growth dynamic of Cigar tobacco leaves

The harvest time is a key factor for cigar leaves with high quality, which varies greatly depending on the environment. Here, we performed a genome-scale mRNA transcriptomic analysis on the cigar cultivar CX-26 (Nicotiana tabacum L.) to evaluate the relationship between gene expression and growth state. The leaves were harvested with 67 (T1), 71(T2) and 75 (T3)-day growth. A total of 80,502 genes were detected in the CX-26 leaves, of which 64,611 genes were annotated on the reference genome. Principal component analysis showed that T1 and T2 leaves had a high overlapping pattern, while T3 leaves were distinct. Indeed, T1 and T2 leaves had fewer differential expressing genes (DEGs), while T3 leaves had 26,456 DGEs from T2 leaves, supporting the distinct growth of T3 leaves. GO annotations mainly enriched the photosynthesis-related metabolic process, catalytic activity and binding biological processes. KEEG analysis identified the key pathways including photosynthesisantenna proteins, plant hormone/MAPK signaling pathway and plant-pathogen interaction. The maturity regulation and defense response-associated hormones abscisic acid and jasmonate acid were higher in the T3 leaves than that in T1 and T2 leaves confirming the KEEG analysis. Furthermore, several photosynthesis-related enzymes and a transcription factor were highlighted in the gene regulatory network, which might regulate the dynamics of carbohydrate metabolism, lipid metabolism and energy metabolism. In summary, our study provides insight into the growth state of CX-26 cigar leaves.

plant biology↗