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Multi-omics identification of therapeutic targets of compound sappan decoction in hepatocellular carcinoma.

BACKGROUND: Compound sappan decoction (CSD) is a multi-herbal traditional Chinese medicine formulation with clinical relevance in hepatocellular carcinoma (HCC). However, its therapeutic mechanisms remain unclear. METHODS: Bioactive compounds of CSD were identified and standardized using pharmacological and chemical databases. Potential targets were predicted via multiple target inference platforms. HCC-related genes were curated from comprehensive disease databases. Summary-data-based Mendelian randomization (SMR) was conducted to infer causal relationships between compound targets and HCC risk using large-scale quantitative trait loci (QTL) datasets and HCC genome-wide association study data. Colocalization analysis, protein-protein interaction (PPI) network construction, and GO/KEGG enrichment were performed on SMR-identified targets. Molecular docking evaluated binding affinities of representative compounds to prioritized targets. RESULTS: A total of 784 overlapping genes between predicted CSD targets and HCC-related genes were subjected to SMR analysis. Among these, 22 targets were significantly associated with HCC risk based on transcriptomic or proteomic QTLs and showed colocalization evidence. Notably, four targets (ADRB2, APOE, SYK, and PGF) were supported by both replication in an independent cohort and strong colocalization. These 22 targets were enriched in apoptosis, PI3K-Akt signaling, redox metabolism, and detoxification pathways. PPI analysis revealed central hubs including MMP9, BCL2, CASP1, and MCL1. Molecular docking demonstrated strong binding of APOE to quercetin, PGF to luteolin-7-olate, and SYK to kaempferol. CONCLUSIONS: CSD may exert therapeutic effects on HCC through modulation of genetically validated targets involved in tumor progression, inflammation, and metabolic reprogramming, supporting its potential clinical utility as an adjunctive treatment strategy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at https://doi.org/10.1007/s12672-026-04740-8.

Caesalpinia↗

Identification of calcium-modulating cyclophilin ligand (CAML) as transducer of angiotensin II-mediated nuclear factor of activated T cells (NFAT) activation.

Angiotensin II (Ang II) plays a central role in cardiovascular physiology and disease. Ang II type I receptor (AT1) is thought to mediate most actions of Ang II. A novel AT1 receptor intracellular partner called AT1 receptor-associated protein (ATRAP) was identified, but its exact function has not been elucidated. A yeast two-hybrid screen using ATRAP as bait identified calcium-modulating cyclophilin ligand (CAML) as an ATRAP partner. Yeast two-hybrid and coimmunoprecipitation analysis demonstrated that the N-terminal hydrophilic domain of CAML (amino acids (aa) 1-189) mediates a specific interaction between ATRAP and CAML. Our analysis also showed that aa 40-82 of ATRAP contribute to this interaction. Bioluminescence resonance energy transfer and intracellular colocalization analysis by immunofluorescence in HEK293 cells verified this association within endoplasmic reticulum vesicular structures. Functionally, transcriptional reporter assays and RNA interference ATRAP experiments demonstrated that ATRAP knockdown increased nuclear factor of activated T cells (NFAT) activity. Overexpression of ATRAP decreased Ang II- or CAML-induced NFAT transcriptional activation, whereas an ATRAP-interacting domain of CAML (aa 1-189) sensitized NFAT activation in response to Ang II. These results indicate that CAML is an important signal transducer for the actions of Ang II in regulating the calcineurin-NFAT pathway and suggest that the interaction of CAML with ATRAP may mediate the Ang II actions in vascular physiology.

Adaptor Proteins, Signal Transducing↗

Large-Scale Proteomic Profiling of Incident Heart Failure and Its Subtypes in Older Adults.

BACKGROUND: Heart failure (HF) and its main subtypes, heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF), impose an enormous health burden on elders. Assessment of the circulating proteome to illuminate pathogenesis could open new opportunities for treatment. METHODS: We conducted a plasma proteomics screen of incident HF and its subtypes in 2 older population-based cohorts, the CHS (Cardiovascular Health Study) and the AGES-RS (Aging, Gene/Environment Susceptibility-Reykjavik Study). The 2 studies used SomaLogic platforms, with 4404 aptamers in common. Multivariable Cox models were fit to evaluate individual-protein associations with HF, HFpEF, and HFrEF separately in each cohort, and study-specific associations were combined by fixed-effects meta-analysis. Replication was performed in the ARIC (Atherosclerosis Risk in Communities) cohort. Two-sample Mendelian randomization of HF and its subtypes, along with colocalization analysis, was performed to support causal inference. RESULTS: Among 8599 participants, 1590 experienced incident HF (536 HFpEF, 471 HFrEF). There were 119 proteins associated with HF, 15 proteins with HFpEF, and 11 proteins with HFrEF, at Bonferroni-corrected significance. Among these, 9 have never previously been identified for cardiovascular diseases, and another 61 represent new associations with incident HF or its subtypes. Of these 70 proteins, 55 of the 66 available replicated externally. Mendelian randomization analysis revealed 7 proteins genetically associated with HF at nominal significance; 2 were separately associated with HFpEF, and another 2 with HFrEF. Seven of these 9 proteins (NPDC1 [neural proliferation differentiation and control protein 1], APOF [apolipoprotein F], LMAN2 [lectin, mannose-binding 2], ADIPOQ [adiponectin], CD14 [cluster of differentiation 14], ARHGAP1 [Rho GTPase-activating protein 1], C9 [complement 9]) showed new, possibly causal associations, although we did not detect evidence for colocalization. CONCLUSIONS: In this large-scale proteomic study involving 3 longitudinal cohorts of older adults, we identified and replicated 55 novel protein markers of HF or its subtypes, and 7 new, possibly causal proteins. These proteins may enhance risk prediction, improve understanding of pathobiology, and help prioritize targets for therapeutic development of these foremost disorders in elders.

Humans↗

WAC, a novel WW domain-containing adapter with a coiled-coil region, is colocalized with splicing factor SC35.

WW domains mediate protein-protein interactions in many intracellular processes. In pre-mRNA splicing, WW domains participate in cross-intron bridging. These WW domains are characterized by a central aromatic block of three tyrosine residues. We identified a novel protein containing the same type of WW domain. The gene encoding the protein, named WAC, is located in human chromosome 10p11.2-10p12.1. A Drosophila melanogaster WAC homolog (CG8949) was identified as a Rosetta stone protein. Domain fusion analysis of the Rosetta stone protein linked WAC to splicing factor SNRP70. WAC existed mainly in a tyrosine-phosphorylated form. Immunofluorescence analysis colocalized WAC with SC35, the marker for pre-mRNA splicing machinery. Our analysis suggests that WAC represents a novel member of WW-domain-containing proteins for RNA processing.

Amino Acid Sequence↗

Integrative multi-omics quantitative trait loci prioritize CASP7 as a candidate protective gene for cataract.

Cataracts are the leading cause of vision loss worldwide. Despite surgery being the only effective treatment, its economic burden highlights the necessity of exploring the pathogenesis of cataracts. In this study, we analyzed 4 large-scale GWAS (genome-wide association study) datasets for cataracts and performed SMR analysis along with heterogeneity in dependent instruments (HEIDI) testing to explore the effects of methylation, expression, and protein QTLs on cataracts. We further validated shared genetic variants through COLOC analysis. Additionally, we searched datasets related to cataracts from the Gene Expression Omnibus (GEO) database for differentially expressed genes (DEGs) and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses. By integrating summary-based Mendelian randomization (SMR) results with bioinformatics findings, CASP7 showed a consistent protective-direction association with cataract risk (mQTL: OR [95% CI] = 0.959 [0.941-0.977], FDR-adjusted P = .039; eQTL: OR [95% CI] = 0.897 [0.860-0.937], FDR-adjusted P = .0046; pQTL: OR [95% CI] = 0.597 [0.483-0.738], FDR-adjusted P = .00083). GEO-based analyses provided transcriptomic support for CASP7 involvement in cataract-related lens biology. These findings prioritize CASP7 as a genetically supported candidate protective gene associated with cataract risk. Because this study is based on public summary-level and transcriptomic datasets, the results should be interpreted cautiously and require functional validation in human lens-relevant systems.

Quantitative Trait Loci↗

Overexpression of caveolin-1 results in increased plasma membrane targeting of glycolytic enzymes: the structural basis for a membrane associated metabolic compartment.

Although membrane-associated glycolysis has been observed in a variety of cell types, the mechanism of localization of glycolytic enzymes to the plasma membrane is not known. We hypothesized that caveolin-1 (CAV-1) serves as a scaffolding protein for glycolytic enzymes and may play a role in the organization of cell metabolism. To test this hypothesis, we over-expressed CAV-1 in cultured A7r5 (rat aorta vascular smooth muscle; VSM) cells. Confocal immunofluorescence microscopy was used to study the distribution of phosphofructokinase (PFK) and CAV-1 in the transfected cells. Areas of interest (AOI) were analyzed in a central Z-plane across the cell transversing the perinuclear region. To quantify any shift in PFK localization resulting from CAV-1 over-expression, we calculated a periphery to center (PC) index by taking the average of the two outer AOIs from each membrane region and dividing by the central one or two AOIs. We found the PC index to be 1.92 +/- 0.57 (mean +/- SEM, N = 8) for transfected cells and 0.59 +/- 0.05 (mean +/- SEM, N = 11) for control cells. Colocalization analysis demonstrated that the percentage of PFK associated with CAV-1 increased in transfected cells compared to control cells. The localization of aldolase (ALD) was also shifted towards the plasma membrane (and colocalized with PFK) in CAV-1 over-expressing cells. These results demonstrate that CAV-1 creates binding sites for PFK and ALD that may be of higher affinity than those binding sites localized in the cytoplasm. We conclude that CAV-1 functions as a scaffolding protein for PFK, ALD and perhaps other glycolytic enzymes, either through direct interaction or accessory proteins, thus contributing to compartmented metabolism in vascular smooth muscle.

Animals↗

Disruption of cadherin/catenin expression, localization, and interactions during HgCl2-induced nephrotoxicity.

The cadherin/catenin complex is an essential regulator of intercellular adhesion and is critical for the establishment of epithelial cell polarity. The purpose of this study was to (1) determine the spatial pattern of cadherin and catenin expression, colocalization, and interaction along the mouse nephron, and (2) investigate the expression, localization, and interaction of proximal tubular cadherins and catenins during mercuric chloride-induced nephrotoxicity. Using a combination of Western blot analysis, colocalization studies, and coimmunoprecipitation, we conclude that two distinct cadherin/catenin complexes exist in adult mouse kidney proximal tubules: N-cadherin/beta-catenin/alpha-catenin and E-cadherin/beta-catenin/alpha-catenin/p120-catenin. In the distal tubule, E-cadherin/beta-catenin/alpha-catenin and E-cadherin/gamma-catenin/alpha-catenin complexes are present. Male C3H mice were challenged with 0-25 micromol/kg mercuric chloride i.p. (6-48 h) to assess the impact of nephrotoxicity on cadherin/catenin complexes. Plasma creatinine and blood urea nitrogen were increased between 6 and 48 h, indicating the onset of renal failure. In addition, histological evaluation demonstrated alterations in the proximal tubules. At 24 h, we observed decreases in Ksp- and N-cadherin, but not in E-cadherin. Additionally, alpha-catenin expression was decreased, in the absence of changes in beta-, gamma-, and p120-catenin. The early stages (6 h) of mercuric chloride-induced nephrotoxicity were associated with disruption of complex integrity. N-cadherin and alpha-catenin localizations were disrupted at 6 h. These changes in cadherin and catenin localization corresponded with a decrease in the coimmunoprecipitation of alpha-catenin with both beta-catenin and N-cadherin. Interestingly, these changes occurred at the same time that aberrant staining of Na+/K(+)-ATPase staining was seen. Taken together, these data suggest that alterations in cadherin and catenin expression, localization, and interaction are associated with nephrotoxicity.

Acute Kidney Injury↗

Localization of LRRK2 to membranous and vesicular structures in mammalian brain.

OBJECTIVE: The PARK8 gene responsible for late-onset autosomal dominant Parkinson's disease encodes a large novel protein of unknown biological function termed leucine-rich repeat kinase 2 (LRRK2). The studies herein explore the localization of LRRK2 in the mammalian brain. METHODS: Polyclonal antibodies generated against the amino or carboxy termini of LRRK2 were used to examine the biochemical, subcellular, and immunohistochemical distribution of LRRK2. RESULTS: LRRK2 is detected in rat brain as an approximate 280kDa protein by Western blot analysis. Subcellular fractionation demonstrates the presence of LRRK2 in microsomal, synaptic vesicle-enriched and synaptosomal cytosolic fractions from rat brain, as well as the mitochondrial outer membrane. Immunohistochemical analysis of rat and human brain tissue and primary rat cortical neurons, with LRRK2-specific antibodies, shows widespread neuronal-specific labeling localized exclusively to punctate structures within perikarya, dendrites, and axons. Confocal colocalization analysis of primary cortical neurons shows partial yet significant overlap of LRRK2 immunoreactivity with markers specific for mitochondria and lysosomes. Furthermore, ultrastructural analysis in rodent basal ganglia detects LRRK2 immunoreactivity associated with membranous and vesicular intracellular structures, including lysosomes, endosomes, transport vesicles, and mitochondria. INTERPRETATION: The association of LRRK2 with a variety of membrane and vesicular structures, membrane-bound organelles, and microtubules suggests an affinity of LRRK2 for lipids or lipid-associated proteins and may suggest a potential role in the biogenesis and/or regulation of vesicular and membranous intracellular structures within the mammalian brain.

Animals↗

Soluble Immune Checkpoint Protein and Lipid Network Associations with All-Cause Mortality Risk: Trans-Omics for Precision Medicine (TOPMed) Program.

Adverse cardiovascular events are emerging with the use of immune checkpoint therapies in oncology. Using datasets in the Trans-Omics for Precision Medicine program (Multi-Ethnic Study of Atherosclerosis, Jackson Heart Study [JHS], and Framingham Heart Study), we examined the association of immune checkpoint plasma proteins with each other, their associated protein network with high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), and the association of HDL-C- and LDL-C-associated protein networks with all-cause mortality risk. Plasma levels of LAG3 and HAVCR2 showed statistically significant associations with mortality risk. Colocalization analysis using genome wide-association studies of HDL-C or LDL-C and protein quantitative trait loci from JHS and the Atherosclerosis Risk in Communities identified TFF3 rs60467699 and CD36 rs3211938 variants as significantly colocalized with HDL-C; in contrast, none colocalized with LDL-C. The measurement of plasma LAG3, HAVCR2, and associated proteins plus targeted genotyping may identify patients at increased mortality risk.

Journal Article↗

Cell-type-specific genetic associations in Lewy body dementia identified using single-cell eQTL-based Mendelian randomization.

BACKGROUND: Lewy body dementia (LBD) is a complex neurodegenerative disorder marked by α-synuclein aggregation and dual impairment of cognitive and motor function.While genome-wide association studies have identified risk loci, the cellular mechanisms linking genetic variation to disease susceptibility remain largely unexplored. METHODS: We performed single-cell transcriptome-wide Mendelian randomization using brain cell-type-specific eQTLs across eight major cell types. Genetic associations were evaluated using inverse-variance weighted models, followed by Bayesian colocalization analysis. Replication was performed in independent stratified LBD cohorts based on APOE ε4 carrier status. Phenome-wide association analysis was included as a supplementary, descriptive assessment of cross-trait associations. RESULTS: Expression of ANKRD65 in excitatory neurons was significantly associated with reduced LBD risk (odds ratio = 0.65, 95 % CI: 0.52-0.81, p = 0.00013). This association passed a false discovery rate of 0.1 and showed strong evidence of colocalization (posterior probability = 0.93). Effect direction was consistent across APOE ε4+ and ε4- LBD subgroups in independent cohorts. No genome-wide significant associations were observed with non-neurological traits in the phenome-wide analysis. CONCLUSIONS: Our findings identify a genetically supported, cell-type-resolved association between ANKRD65 expression in excitatory neurons and LBD risk. This study demonstrates the value of integrating cell-resolved transcriptomic regulation with genetic inference to pinpoint functionally relevant targets in neurodegenerative diseases.

Humans↗

Single-molecule detection and probe strategies for rapid and ultrasensitive genomic detection.

This paper reviews the current state-of-the-art development of single-molecule detection (SMD)-based methods for ultrasensitive and specific analysis of genomic sequences. We first discuss several newly devised single fluorescent probe strategies that allow separation-free detection of low-abundance DNA sequences, such as quantum dot (QD)-mediated fluorescence resonance energy transfer (FRET) technology and dual-color fluorescence coincidence and colocalization analysis. Various schemes toward single DNA sizing and sequencing in solutions or on surfaces are also reviewed. In the end, we summarize the different microfluidic approaches developed for use with SMD to facilitate rapid, low-volume and quantitative analysis, such as electrokinetic and hydrodynamic single-molecule manipulation techniques.

DNA Probes↗

Quantitative microscopy reveals 3D organization and kinetics of endocytosis in rat hepatocytes.

In order to demonstrate the power of quantitative microscopy, the endocytic apparatus of rat hepatocytes was reexamined using in situ liver and short term cultured hepatocyte couplets that were allowed to internalize endocytic markers for various time intervals. Correlative confocal light and electron microscopy demonstrate a tubulovesicular reticulum representing the endocytic apparatus. Volume and membrane area account for 2% of cell volume and 30% plasma membrane surface. Colocalization analysis demonstrated that pathway-specific ligands and fluid-phase markers enter EEA1-positive vesicles, the early endosomal compartment, immediately after internalization. These vesicles are translocated rapidly from basolateral to perinuclear and apical locations. Ligands are sorted within 5 min to their respective pathways. Sequential colocalization of an asialoglycoprotein-pulse with rab7 and lamp3 demonstrates that early endosomes change into or fuse with late endosomes and lysosomes. Alternatively, markers are sequestered into the common endosome consisting of rab11-positive, long tubules that originate from early endosomes and show an affinity for the transcytotic marker pIgA and its receptor. This compartment mediates transcytosis by delivering the receptor-ligand complex to the subapical compartment, a set of apical, rab11-positive vesicles, which are connected to the tubular reticulum. We conclude that vesicular traffic between preexisting compartments, maturation or fusion of endocytic organelles, and transport in tubules act in concert and together mediate transport between compartments of a tubulovesicular endocytic apparatus. In addition, we show that quantitative microscopy using high resolution data sets can detect and characterize kinetics of various parameters thus adding a dynamic component to 3D information.

Animals↗

ssDNA-dependent colocalization of adeno-associated virus Rep and herpes simplex virus ICP8 in nuclear replication domains.

The subnuclear distribution of replication complex proteins is being recognized as an important factor for the control of DNA replication. Herpes simplex virus (HSV) single-strand (ss)DNA-binding protein, ICP8 (infected cell protein 8) accumulates in nuclear replication domains. ICP8 also serves as helper function for the replication of adeno-associated virus (AAV). Using quantitative 3D colocalization analysis we show that upon coinfection of AAV and HSV the AAV replication protein Rep and ICP8 co-reside in HSV replication domains. In contrast, Rep expressed by a recombinant HSV, in the absence of AAV DNA, displayed a nuclear distribution pattern distinct from that of ICP8. Colocal ization of Rep and ICP8 was restored by the reintroduction of single-stranded AAV vector genomes. In vitro, ICP8 displayed direct binding to Rep78. Single-stranded recombinant AAV DNA strongly stimulated this interaction, whereas double-stranded DNA was ineffective. Our findings suggest that ICP8 by its strong ssDNA-binding activity exploits the unique single-strandedness of the AAV genome to form a tripartite complex with Rep78 and AAV ssDNA. This novel mechanism for recruiting components of a functional replication complex directs AAV to subnuclear HSV replication compartments where the HSV replication complex can replicate the AAV genome.

Active Transport, Cell Nucleus↗

Quantitative analysis of neuronal nitric oxide synthase-immunoreactive neurons in the mouse hippocampus with optical disector.

A detailed quantitative analysis of immunocytochemically identified nonprincipal neurons containing neuronal nitric oxide synthase (nNOS) was performed on the mouse hippocampus, with particular reference to the dorsoventral gradient. The present study applied two variations of a stereologic technique, the optical disector--one that used confocal laser-scanning microscope optical sections to examine colocalization of nNOS and glutamic acid decarboxylase 67 (GAD67), and the other that used conventional thick sections to examine numerical densities (NDs) and cell sizes of nNOS-immunoreactive (IR) neurons. Colocalization analysis indicated that practically all nNOS-IR neurons (97.6%) were GAD67-IR, whereas a part of the GAD67-IR neurons (about 30%) were nNOS-IR in the whole hippocampus at both dorsal and ventral levels. The percentages of GAD67-IR neurons containing nNOS were higher in the dentate gyrus (DG, about 50%), and lower in the Ammon's horn (about 20%). Laminar analysis revealed that the majority of GAD67-IR neurons contained nNOS in the stratum lacunosum-moleculare of the CA3 region (about 60%) and in the molecular layer of the DG (about 80%). The NDs of nNOS-IR neurons in the whole hippocampus showed a dorsoventral gradient, which increased from dorsal (1.6 x 10(3)/mm3) to ventral (2.2 x 10(3)/mm3) levels. The NDs were relatively higher in the principal cell layers, where about 40% of nNOS-IR neurons were situated both in the Ammon's horn and DG. The mean cell sizes of nNOS-IR neurons showed no remarkable laminar differences or dorsoventral gradient in the Ammon's horn, but they were extensively larger in the hilus of the DG than in other layers. These results indicate that nNOS-IR neurons in the mouse hippocampus represent a subpopulation of gamma-aminobutyric acid (GABA)ergic neurons and suggest that the laminar distributions of nNOS-IR neurons related to possible functional heterogeneity of GABAergic neurons in each hippocampal layer.

Animals↗

Exploring the shared genetic basis of attention-deficit/hyperactivity disorder and obstructive sleep apnea: A multi-omics analysis.

BACKGROUND: Observational studies have suggested an association between attention-deficit/hyperactivity disorder (ADHD) and obstructive sleep apnea (OSA), but these findings are often inconsistent due to potential biases from medication use, and varying diagnostic criteria. Genetic analyses can help mitigate these confounding factors, providing additional evidence. METHODS: This study evaluated the genetic correlations between ADHD and OSA using Genome-wide association study (GWAS) summary data, applying linkage disequilibrium score regression (LDSC) and SUPER GeNetic cOVariance Analyzer (SUPERGNOVA). Cross-trait association and colocalization analysis identify potential pleiotropic loci. Tissue enrichment analysis and gene-level analysis of shared genes between OSA and ADHD was conducted. Additionally, bidirectional Mendelian randomization was used to assess potential causal relationships. RESULTS: We found significant genetic correlations between ADHD and OSA (rg = 0.309, p = 3.252E-27), and identified 8 novel pleiotropic loci through cross-trait association analysis. Tissue enrichment analysis showed that these shared genes were primarily concentrated in brain tissues, particularly in deep gray matter regions, and were associated with immune and inflammatory pathways. Forward Mendelian Randomization analysis showed that ADHD was significantly associated with the risk of OSA (OR 1.070, 95 % CI 1.013-1.130, p = 0.016), and reverse analysis showed that OSA was significantly associated with the risk of ADHD (OR 1.240, 95 % CI 1.106-1.390, p = 2.213E-4). CONCLUSION: The findings of this study show a significant positive genetic correlation between ADHD and OSA and each is a risk factor for the other. Inflammation in specific brain regions may be the underlying mechanism for their comorbidity.

Humans↗

Linking cortical structure and delirium in the elderly: insights from cohort study and shared genetic risk analysis.

BACKGROUND: This study aimed to assess the association between regional cortical changes measured via baseline magnetic resonance imaging (MRI) and the incidence of delirium. METHODS: Observational associations were assessed using a prospective cohort from the UK Biobank and an independent clinical cohort. The population-based study included participants aged 60 years or older who had undergone structural brain MRI since 2014. Regional cortical volume, mean thickness, and surface area were extracted based on the Desikan-Killiany cortical atlas. Delirium was defined using ICD-10 diagnostic codes. Additionally, preoperative brain MRI images from participants in another cohort were collected and automatically segmented using deep learning algorithms to obtain cortical measurements. Logistic analysis was performed to investigate the associations between cerebral cortical structure and delirium risk. Lastly, genome-wide association study data derived from the ENIGMA Consortium and FinnGen Biobank were utilized to conduct conditional/conjunctional false discovery rate (cond/conjFDR) analyses to identify shared genetic loci associated with cortical structures and delirium. RESULTS: This observational analysis included 31,890 participants from the UK Biobank and 152 participants from an independent cohort. In the UK Biobank cohort, decreased cortical thickness in the 17 regions was associated with a significantly increased risk of delirium. Similarly, a preoperative reduction in cortical volume in 7 regions was associated with an increased risk of delirium in the independent cohort. Besides, 100 single-nucleotide polymorphisms (SNPs) were identified as significantly associated with cortical structures when conditioned on delirium. Finally, colocalization analysis demonstrated that these pleiotropic risk loci modulated the expression of NT5C2, RGP1, CCDC25, TPM2, EEF1AKMT2, IQANK1 and LHPP in blood and brain tissues. CONCLUSION: Regional cortical atrophy is associated with an increased risk of delirium in the elderly. Brain MRI examinations may be beneficial for preoperative delirium risk assessment in elderly individuals undergoing elective surgery.

Humans↗

Essential role for activation of the Polycomb group (PcG) protein chromatin silencing pathway in metastatic prostate cancer.

The Polycomb group (PcG) gene BMI1 is required for the proliferation and self-renewal of normal and leukemic stem cells. Overexpression of Bmi1 oncogene causes neoplastic transformation of lymphocytes and plays essential role in pathogenesis of myeloid leukemia. Another PcG protein, Ezh2, was implicated in metastatic prostate and breast cancers, suggesting that PcG pathway activation is relevant for epithelial malignancies. Whether an oncogenic role of the BMI1 and PcG pathway activation may be extended beyond the leukemia and may affect progression of solid tumors as well remains unknown. Here we demonstrate that activation of the BMI1 oncogene-associated PcG pathway plays an essential role in metastatic prostate cancer, thus mechanistically linking the pathogenesis of leukemia, self-renewal of stem cells, and prostate cancer metastasis. To characterize the functional status of the PcG pathway in metastatic prostate cancer, we utilized advanced cell- and whole animal-imaging technologies, gene and protein expression profiling, stable siRNA-gene targeting, and tissue microarray (TMA) analysis in relevant experimental and clinical settings. We demonstrate that in multiple experimental models of metastatic prostate cancer both BMI1 and Ezh2 genes are amplified and gene amplification is associated with increased expression of corresponding mRNAs and proteins. For the first time, we provide images of human prostate carcinoma metastasis precursor cells isolated from blood and shown to overexpress both BMI1 and Ezh2 oncoproteins. Consistent with the PcG pathway activation hypothesis, increased BMI1 and Ezh2 expression in metastatic cancer cells is associated with elevated levels of H2AubiK119 and H3metK27 histones. Quantitative immunofluorescence colocalization analysis and expression profiling experiments documented increased BMI1 and Ezh2 expression in clinical prostate carcinoma samples and demonstrated that high levels of BMI1 and Ezh2 expression are associated with markedly increased likelihood of therapy failure and disease relapse after radical prostatectomy. Gene-silencing analysis reveals that activation of the PcG pathway is mechanistically linked with highly malignant behavior of human prostate carcinoma cells and is essential for in vivo growth and metastasis of human prostate cancer. We conclude that the results of experimental and clinical analyses indicate the important biological role of the PcG pathway activation in metastatic prostate cancer. Our work suggests that the PcG pathway activation is a common oncogenic event in pathogenesis of metastatic solid tumors and provides justification for development of small molecule inhibitors of the PcG chromatin silencing pathway as a novel therapeutic modality for treatment of metastatic prostate cancer.

Adenocarcinoma↗

Differential induction of heat shock mRNA in oligodendrocytes, microglia, and astrocytes following hyperthermia.

A time course analysis of hsp70 mRNA induction in response to a physiologically relevant increase in body temperature of 2.6 degrees C was performed in the rabbit forebrain. A protocol that combined in situ hybridization and cytochemistry on the same tissue section was employed to identify reactive glial cell types. Cytochemical markers for astrocytes, microglia, and oligodendrocytes were utilized in combination with a DIG-labelled hsp70 riboprobe, which permitted mRNA localization at high resolution. Four glial cell body-enriched regions of the rabbit forebrain were examined, namely, cortical layer 1, hippocampal fissure, corpus callosum, and fimbria. Maximal hsp70 mRNA induction was observed in 2 and 3 h hyperthermic animals. The colocalization analysis demonstrated that hsp70 mRNA was induced in oligodendrocytes and microglia, but not in forebrain GFAP positive astrocytes. In addition, cell counts were performed which showed that almost all oligodendrocytes induced hsp70 mRNA while a subpopulation of microglial cells responded. These data are consistent with the notion that oligodendrocytes, microglia, and astrocytes exhibit distinct thresholds for activation of the heat shock response following a physiologically relevant increase in body temperature.

Animals↗