👤 Zhidong Cen

Near-infrared (NIR)-II fluorescence imaging at 1000-1700 nm is widely used for deep-tissue visualisation and disease theranostics in the brain, with NIR-II theranostics greatly improving imaging resolution, imaging depth, and therapeutic efficacy. However, the extreme lack of molecular design in NIR-II fluorophores has slowed the discovery of bright candidates and restricted their efficacious application in brain theranostics. Here, we develop a covalent bond locking (CBL) strategy that enables the feasible design of bright NIR-II fluorophores by effectively restricting the twisted intramolecular charge transfer state. These spirofluorophores incorporate terminally spiro-donor groups, which leads to a higher molar extinction coefficient and improved quantum yield than non-spirofluorophores do. With bright and stable NIR-II fluorescence advantages, we demonstrate that CBL nanoparticles (NPs) of spirofluorophores achieve multiscale high-resolution NIR-II angiography via one-photon fluorescence and two-photon fluorescence bioimaging simultaneously. With apolipoprotein E (ApoE) modification, CBL@ApoE NPs achieve enhanced blood-brain barrier permeability, facilitating superior brain glioma theranostics. This work proposes a CBL strategy to engineer highly bright NIR-II fluorescent fluorophores, providing a reliable nanoplatform for deep brain theranostics that can be effectively delivered across biological barriers to target brain tumors. Show less

The clinical interpretation of Alzheimer's disease (AD) is frequently complicated by the prevalence of missense variants designated as being of uncertain significance within associated genes. Conventional computational prediction tools often overlook disease-specific pathophysiological contexts and lack pertinence and interpretability. Therefore, the present study aimed to develop a novel, interpretable framework for predicting the pathogenicity of AD missense variants by integrating transcriptomic and proteomic data enrichment patterns with machine learning methods. A cross-sectional variant-level analysis was performed using publicly available databases. Missense variants in APOE, APP, PSEN1, PSEN2, SORL1, and TREM2 reported in AD patients were retrieved from Alzforum and compared with missense variants from individuals without neurological diseases, as cataloged in the gnomAD v2.1.1 non-neuro subset. Variants were annotated with tissue-specific expression, secondary structure, relative solvent accessibility, and other functional features using tools like AlphaFold. Enrichment of specific features was assessed with Fisher's exact tests with Bonferroni correction for multiple comparisons. Given that PSEN1 showed the strongest enrichment signals, six machine-learning algorithms were trained on PSEN1 variants to distinguish AD-associated variants from gnomAD variants, using a 10 × 5 nested cross-validation scheme. External validation was conducted using PSEN1 missense variants from ClinVar annotated as pathogenic/likely pathogenic or benign/likely benign. Model performance was compared with SIFT and PolyPhen-2, and interpretability was evaluated by feature ablation and SHapley Additive exPlanations analyses. AD-associated variants exhibited statistically significant enrichment within some transcriptomic or proteomic features, with PSEN1 contributing significantly to the enrichment observed across these features. Random forest and gradient boosting models achieved high performance in the internal training dataset and maintained high recall in the external validation dataset, outperforming SIFT and approaching the performance of PolyPhen-2. Relative solvent accessibility was the most discriminative individual feature, while regional and topological features provided complementary discriminative power. This integrative, multi-omics framework links disease-specific enrichment patterns with interpretable gene-level machine learning for AD missense variants. The results highlight the importance of expression level, structural context, etc. for PSEN1 variant pathogenicity and may help prioritize variants for functional studies. Further validation in additional genes and independent cohorts is warranted prior to any clinical application. Show less

Achieving long persistent luminescence (LPL) in fully organic materials with both hour-level duration and high thermal stability remains a fundamental challenge attributable to rapid exciton quenching and poor resistance to thermal disturbances. Herein, a trap engineering strategy is reported based on rigidified triphenylamine derivatives and boronic ester functionalization embedded in recycled poly(ethylene terephthalate) (PET), enabling the first fully organic polymer-based LPL system that exhibits simultaneously ultralong LPL and exceptional thermal robustness. Molecular conformation locking and optimized donor-acceptor charge transfer lead to deep trap states (≈1.03 eV), resulting in ambient LPL lifetimes exceeding 12 h. Remarkably, the luminescence is thermally enhanced by over 56 times at 500 K, rivaling high-performance inorganic phosphors. In addition, 980 nm near-infrared photo excitation further amplifies the emission, showcasing strong photo-stimulated luminescence capability. Taking advantage of PET's processability, 3D-printed luminescent structures are fabricated that retain LPL functionality and enable spatially resolved thermal sensing and real-time damage detection. This work not only introduces a sustainable and scalable platform for advanced thermal imaging and optoelectronics, but also sets a new benchmark in the design of heat-resistant organic LPL materials, bridging the gap between high-performance functionality and environmental compatibility. Show less

Lung adenocarcinoma (LUAD) remains the leading cause of cancer deaths worldwide. Apurinic/apyrimidinic endonuclease 1 (APE1), an enzyme integral to DNA repair and redox signaling, is notably upregulated in LUAD. Here we reveal that APE1 amplification, primarily via allele duplication, strongly correlates with poor prognosis in LUAD patients. Using human LUAD cell lines and a Show less

Endometriosis is caused by the migration of endometrial cells to locations outside the uterine lining. Despite the increasing prevalence of endometriosis, there has been limited research on genetic effects, and its molecular mechanisms remain unclear. This study aimed to investigate the mechanisms underlying the development of endometriosis and to identify new genetic targets for endometriosis by integrating data from gene chips, single-cell mapping, and genome-wide association study databases. Using the Gene Expression Omnibus database, we downloaded data on normal endometrium, eutopic endometrium, and ectopic lesion tissues to explore the differentially expressed genes (DEGs) between normal and eutopic endometrium, and between eutopic and ectopic endometrium. Assessment of the relationships between DEGs and endometriosis involved differential expression, expression quantitative trait loci (eQTL), and Mendelian randomization (MR) analyses. Two single-cell atlas datasets were then analyzed to explore the mechanisms underlying disease development and progression. Intersection of MR results with DEGs between normal and eutopic endometrium highlighted 28 candidate biomarker genes (17 upregulated and 11 downregulated). Similarly, we identified two additional candidate biomarker genes by intersecting the DEGs between eutopic and ectopic endometrium with MR results. Among these 30 candidates, further filtering using single-cell datasets revealed that the histamine N-methyltransferase (HNMT), coiled-coil domain containing 28 A (CCDC28A), fatty acid desaturase 1 (FADS1) and mahogunin ring finger 1 (MGRN1) genes were differentially expressed between the normal and eutopic groups, consistent with transcriptomic and MR results. Our findings suggested that eutopic endometrium exhibits epithelial-mesenchymal transition (EMT). Cell communication analysis focused on ciliated epithelial cells expressing CDH1 and KRT23 revealed that, in the eutopic endometrium, ciliated epithelial cells are strongly correlated and interact with natural killer cells, T cells, and B cells. We identified four novel biomarker genes and found evidence for EMT in the eutopic endometrium. The mechanism of endometriosis progression may be closely related to EMT and changes in the immune microenvironment triggered by damage to ciliated epithelial cells. Show less

HUWE1, a member of HECT E3 ubiquitin ligase family, is implicated in a variety of cellular processes. Recent studies find that HUWE1 also plays critical roles in germ cell development and inactivation of HUWE1 causes germ cell loss in both male and female mice. In this study, we found that Huwe1 was also highly expressed in testicular Sertoli cells. Inactivation of Huwe1 in Sertoli cells resulted in loss of cell polarity, which in turn caused germ cells loss and male infertility. Further study revealed that dysregulation in the expression of cytoskeletal and adhesion-related molecules, as well as a significant increase in EMT-related trans-factors SNAI1&2 in Huwe1-deficient Sertoli cells. Intriguingly, the protein level of WT1 was significantly increased in Huwe1-deficient Sertoli cells, and overexpression of Wt1 in Sertoli cells also caused the defects in spermatogenesis which was consistent with Huwe1 CKO mouse model. Furthermore, the defect of spermatogenesis in Huwe1 CKO mice was partially rescued by deleting one allele of Wt1 gene. Mechanistic studies revealed that WT1 interacts with HUWE1 protein and it could be ubiquitinated by HUWE1. Our study demonstrates that HUWE1 is involved in the establishment of Sertoli cell polarity mainly by regulating the protein level of WT1 gene. Show less

Circular RNAs (circRNAs) are non-coding RNAs with covalently closed structures that modulate the progression of hepatocellular carcinoma (HCC). Here, we explored whether circ₀₀₀₈₀₄₃ regulated the biological function of HCC cells. Quantitative real-time polymerase chain reaction (qPCR) was used to detect circ₀₀₀₈₀₄₃, microRNA (miR)-326, and RAB21 levels. Expression of E-cadherin, N-cadherin, and vimentin was assessed using qPCR. Cell proliferation, migration, and invasion were evaluated using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, and transwell assays. Xenograft tumors were used to evaluate cell growth Show less

Recent studies have identified that circular RNAs (circRNAs) have an important role in cancer via their well-recognized sponge effect on miRNAs, which regulates a large variety of cancer-related genes. However, only a few circRNAs have been well-studied in renal cell carcinoma (RCC) and their regulatory function remains largely elusive. Bioinformatics approaches were used to characterize the differentially expressed circRNAs in our own circRNA-sequencing dataset, as well as two public circRNA microarray datasets. CircNTNG1 (hsa_circ₀₀₀₂₂₈₆₎ was identified as a potential tumor-suppressing circRNA. Transwell assay and CCK-8 assay were used to assess phenotypic changes. RNA pull-down, luciferase reporter assays and FISH experiment were used to confirm the interactions among circNTNG1, miR-19b-3p, and HOXA5 mRNA. GSEA was performed to explore the downstream pathway regulated by HOXA5. Immunoblotting, chromatin immunoprecipitation, and methylated DNA immunoprecipitation were used to study the mechanism of HOXA5. In all three circRNA datasets, circNTNG1, which was frequently deleted in RCC, showed significantly low expression in the tumor group. The basic properties of circNTNG1 were characterized, and phenotype studies also demonstrated the inhibitory effect of circNTNG1 on RCC cell aggressiveness. Clinically, circNTNG1 expression was associated with RCC stage and Fuhrman grade, and it also served as an independent predictive factor for both OS and RFS of RCC patients. Next, the sponge effect of circNTNG1 on miR-19b-3p and the inhibition of HOXA5 by miR-19b-3p were validated. GSEA analysis indicated that HOXA5 could inactivate the epithelial-mesenchymal transition (EMT) process, and this inactivation was mediated by HOXA5-induced SNAI2 (Slug) downregulation. Finally, it was confirmed that the Slug downregulation was caused by HOXA5, along with the DNA methyltransferase DNMT3A, binding to its promoter region and increasing the methylation level. Based on the experimental data, in RCC, circNTNG1/miR-19b-3p/HOXA5 axis can regulate the epigenetic silencing of Slug, thus interfering EMT and metastasis of RCC. Together, our findings provide potential biomarkers and novel therapeutic targets for future study in RCC. Show less

Metastasis is the dominant cause of cancer-related mortality. Metastasis-associated with colon cancer protein 1 (MACC1) has been proven to play a critical role in cancer metastasis. However, the prometastatic role of MACC1 in regulating the pancreatic cancer (PC) metastatic phenotype remains elusive. Here, we report that MACC1 is highly expressed in The Cancer Genome Atlas (TCGA) and tissue microarray (TMA) and identified as a good indicator for poor prognosis. Overexpression or knockdown of MACC1 in PC cells correspondingly promoted or inhibited pancreatic cancer cell migration and invasion in a MET proto-oncogene receptor tyrosine kinase (MET)-independent manner. Notably, knockdown of MACC1 in PC cells markedly decreased the liver metastatic lesions in a liver metastasis model. Mechanistically, MACC1 binds to the epithelial-mesenchymal transition (EMT) regulator snail family transcriptional repressor 1 (SNAI1) to drive EMT via upregulating the transcriptional activity of SNAI1, leading to the transactivation of fibronectin 1 (FN1) and the trans-repression of cadherin 1 (CDH1). Collectively, our results unveil a new mechanism by which MACC1 drives pancreatic cancer cell metastasis and suggest that the MACC1-SNAI1 complex-mediated mesenchymal transition may be a therapeutic target in pancreatic cancer. Show less

Leucine-rich repeat and immunoglobulin domain-containing protein (LINGO)-1 is expressed in neural stem cells, and its neutralization results in sustained neuronal immaturity. Thus, targeted inhibition of LINGO-1 via RNA interference may enhance transplanted neural stem cell survival and neuronal differentiation in vivo. Furthermore, LINGO-1 RNA interference in neural stem cells represents a potential therapeutic strategy for spinal cord injury. Department of Spine Surgery, First Affiliated Hospital of Sun Yat-sen University. Translational Medicine Center Research Laboratory, First Affiliated Hospital of Sun Yat-sen University. Female Sprague-Dawley rats. The animals were divided into three groups that underwent laminectomy and complete spinal cord transection accompanied by transplantation of control-RNA interference-treated or LINGO-1-RNA interference-treated neural stem cells at the injured site in vivo. In vitro, neural stem cells were divided into four groups for the following treatments: control, control RNA interference lentivirus, LINGO-1 RNA interference lentivirus and LINGO-1 complementary DNA lentivirusand the Key Projects of the Natural Science Foundation of Guangdong Province (No. S2013020012818). Neural stem cells in each treatment group were examined for cell survival and neuronal differentiation in vitro and in vivo via immunofluorescence and Western blot analysis. Axonal regeneration and tissue repair were assessed via retrograde tracing using Fluorogold, electron microscopy, hematoxylin-eosin staining and MRI. Rats were also examined for functional recovery based on the measurement of spinal cord-evoked potentials and the Basso-Beattie-Bresnahan score. LINGO-1-RNA interference-treated neural stem cell transplantation increased tissue repair and functional recovery of the injured spinal cord in rats. Similarly, LINGO-1 RNA interference increased neural stem cell survival and neuronal differentiation in vitro. The mechanism underlying the effect of LINGO-1 RNA interference on the injured rat spinal cord may be that the significant inhibition of LINGO-1 expression in neural stem cells inactivated the RhoA and Notch signaling pathways, which act downstream of LINGO-1. Our findings indicate that transplantation of LINGO-1-RNA interference-treated neural stem cells facilitates functional recovery after spinal cord injury and represents a promising potential strategy for the repair of spinal cord injury. Show less

We used a complete spinal cord transection model and locomotor function, histological, and immunohistochemical examinations to evaluate the effects of local injection of lentivirus/LINGO-1-short hairpin RNA (VL) on rats with spinal cord injury (SCI). To demonstrate the neuroregenerative and neuroprotective effects of LINGO-1 RNAi on complete transection SCI rats. LINGO-1 has been reported as a negative regulator of axonal sprouting and its antagonist was determined to improve functional outcomes in SCI rats. However, it has not been assessed whether blockade of LINGO-1 mediated by lentivirus vectors could stimulate neural recovery after SCI. Complete spinal cord transection was made at T10 level. Suspension of lentivirus vectors encoding LINGO-1-short hairpin RNA was injected into the lesion gap. Controls received control vectors in the same manner and the sham group was subjected to laminectomy only. The Basso-Beattie-Bresnahan scale and surface righting reflex test were used to evaluate functional outcomes. Finally, the spinal cords were harvested for histological and immunohistochemical analysis. The treatment with VL improved Basso-Beattie-Bresnahan scores and surface righting reflex after SCI. Tissue repair was facilitated and the cavity area was significantly decreased in VL-treated animals. More sprouting and myelinated nerve fibers were detected within the injured site in the VL group as compared with the control. In addition, the number of survival neurons and oligodendrocytes around the epicenter was notably higher under the VL condition. Local injection of lentivirus/LINGO-1-short hairpin RNA after complete transection of spinal cord resulted in meaningful histological and functional outcomes in rats. The mechanism of VL protection may be related to its promotion of axonal sprouting, remyelination, and cell survival. Show less

Lingo-1 is selectively expressed on both oligodendrocytes and neurons in the central nervous system (CNS) and serves as a key negative regulator of nerve regeneration, implying a therapeutic target for spinal cord injury (SCI). Here we described a strategy to knock-down Lingo-1 expression in vivo using lentiviral vectors encoding Lingo-1 short harpin interfering RNA (shRNA) delivered by Pluronic F-127 (PF-127) gel, a non-cytotoxic scaffold and gene delivery carrier, after the complete transection of the T10 spinal cord in adult rats. We showed administration of PF-127 encapsulating Lingo-1 shRNA lentiviral vectors efficiently down-regulated the expression of Lingo-1, and exhibited transduction efficiency comparable to using vectors alone in oligodendrocyte culture in vitro. Furthermore, similar silencing effects and higher transfection efficiency were observed in vivo when Lingo-1 shRNA was co-delivered to the injured site by PF-127 gel with lower viral concentrations. Cografting of gel and Lingo-1 RNAi significantly promoted functional recovery and nerve regeneration, enhanced neurite outgrowth and synapses formation, preserved myelinated axons, and induced the proliferation of glial cells. In addition, the combined implantation also improved neuronal survival and inhibited cell apoptosis, which may be associated with the attenuation of endoplasmic reticulum (ER) stress after SCI. Together, our data indicated that delivering Lingo-1 shRNA by gel scaffold was a valuable treatment approach to SCI and PF-127 delivery of viral vectors to the spinal cord may provide strategy to study and develop therapies for SCI. Show less