Strong Expression Research Articles

Survival impact of hypoxia-inducible factor-1 alpha (HIF-1α) in Nucleophosmin1 mutated acute myeloid leukemia.

Nucleophosmin1 (NPM1) mutated acute myeloid leukemia (AML) without FLT3-ITD mutation is classified as a favorable risk AML which responds well to cytarabine therapy. Hypoxia-inducible factor-1 alpha (HIF-1α) promotes leukemic cell survival and maintains leukemic stem cell quiescence possibly contributing to cytarabine resistance. This study evaluated HIF-1α expression using immunohistochemistry in bone marrow of 29 newly diagnosed NPM1+FLT3-ITD- normal karyotype AML patients and analyzed its correlation with survival. All patients achieved complete remission after standard induction chemotherapy and proceeded to cytarabine consolidations. Positive HIF-1α staining with golgi body pattern and strong cytoplasmic HIF-1α expression was identified in 34.5% and 58.6% of patients, respectively. The expression of golgi body or strong cytoplasmic HIF-1α expression was related to increased relapse (p = 0.048) with significantly inferior relapse-free survival (RFS, p = 0.042). Using multivariate analysis, extramedullary disease at diagnosis was revealed as an independent prognostic factor for adverse RFS (hazard ratio [HR] 3.82; 95% confidence interval [CI] 1.26-11.55, p = 0.018), while golgi body or strong cytoplasmic HIF-1α expression showed a trend toward poor RFS (HR 3.56; 95% CI 1.00-12.69, p = 0.050). In summary, high HIF-1α expression is potentially a baseline prognostic biomarker for poor RFS and cytarabine resistance in NPM1+FLT3-ITD- AML. Further studies with the large number of patients are warranted.

Wilms’ Tumor 1 Gene Expression as a Predictive Marker for Clinical Outcome of Acute Myeloid Leukemia in Iraqi Population: A Prospective Study

Background: Wilms' tumor gene 1 (WT1), a tumor-associated antigen (TAA), is expressed in many types of cancer. Most acute leukemia patients have a quantitatively detectable and strong expression of it. Objectives: To analyze WT1 expression levels as a predictor of clinical outcomes at the time of diagnosis of de novo leukemia and to monitor tumor progression during treatment. Methods: A total of 71 patients with acute myeloid leukemia (AML) were separated into two groups: twenty-nine de novo AML patients upon presentation and 25 with AML at the time of initial induction. The second induction included 17 AML patients and ten healthy volunteers who served as controls in this study. The WT1 gene was tested using a real-time PCR with the Cyber Green assay. Results: Patients with acute myeloid leukemia had considerably greater levels of WT1 gene expression than controls (27.3 vs. 5.5). In terms of clinical outcomes, WT1 gene overexpression was substantially related to non-responsive AML patients compared to complete response at diagnosis (27.3 vs. 22.15). However, there is no substantial difference between instances following induction. Conclusions: The WT1 tumor antigen may serve as an early diagnostic for acute leukemia prognosis. Improved clinical outcomes have been linked to reduced WT1 levels. A high amount, on the other hand, was linked to a poor prognosis for people with AML, although more research is needed.

On Transforming Reinforcement Learning With Transformers: The Development Trajectory.

Transformers, originally devised for natural language processing (NLP), have also produced significant successes in computer vision (CV). Due to their strong expression power, researchers are investigating ways to deploy transformers for reinforcement learning (RL), and transformer-based models have manifested their potential in representative RL benchmarks. In this paper, we collect and dissect recent advances concerning the transformation of RL with transformers (transformer-based RL (TRL)) to explore the development trajectory and future trends of this field. We group the existing developments into two categories: architecture enhancements and trajectory optimizations, and examine the main applications of TRL in robotic manipulation, text-based games (TBGs), navigation, and autonomous driving. Architecture enhancement methods consider how to apply the powerful transformer structure to RL problems under the traditional RL framework, facilitating more precise modeling of agents and environments compared to traditional deep RL techniques. However, these methods are still limited by the inherent defects of traditional RL algorithms, such as bootstrapping and the "deadly triad". Trajectory optimization methods treat RL problems as sequence modeling problems and train a joint state-action model over entire trajectories under the behavior cloning framework; such approaches are able to extract policies from static datasets and fully use the long-sequence modeling capabilities of transformers. Given these advancements, the limitations and challenges in TRL are reviewed and proposals regarding future research directions are discussed. We hope that this survey can provide a detailed introduction to TRL and motivate future research in this rapidly developing field.

Spatial transcriptomics in focal cortical dysplasia type IIb

Focal cortical dysplasia (FCD) type IIb (FCD IIb) is an epileptogenic malformation of the neocortex that is characterized by cortical dyslamination, dysmorphic neurons (DNs) and balloon cells (BCs). Approximately 30–60% of lesions are associated with brain somatic mutations in the mTOR pathway. Herein, we investigated the transcriptional changes around the DNs and BCs regions in freshly frozen brain samples from three patients with FCD IIb by using spatial transcriptomics. We demonstrated that the DNs region in a gene enrichment network enriched for the mTOR signalling pathway, autophagy and the ubiquitin‒proteasome system, additionally which are involved in regulating membrane potential, may contribute to epileptic discharge. Moreover, differential expression analysis further demonstrated stronger expression of components of the inflammatory response and complement activation in the BCs region. And the DNs and BCs regions exhibited common functional modules, including regulation of cell morphogenesis and developmental growth. Furthermore, the expression of representative proteins in the functional enrichment module mentioned above was increased in the lesions of FCD IIb, such as p62 in DNs and BCs, UCHL1 in DNs, and C3 and CLU in BCs, which was confirmed via immunohistochemistry. Collectively, we constructed a spatial map showing the potential effects and functions of the DNs and BCs regions at the transcriptomic level and generated publicly available data on human FCD IIb to facilitate future research on human epileptogenesis.

Prognostic significance of YKL-40 expression in canine cutaneous mast cell tumors

BackgroundYKL-40, a secretory glycoprotein, is involved in tumor cell proliferation, metastasis, and angiogenesis in human cancers. Its overexpression has been correlated with unfavorable prognosis in many human cancers. In veterinary medicine, elevated YKL-40 levels in the serum of canine cutaneous mast cell tumors (cMCTs) were observed in our previous study. However, the expression pattern of YKL-40 in canine cMCT tissues, along with its association with clinical and pathological features, is still unknown. This study aims to retrospectively investigate the expression level of YKL-40 in the tissues of canine cMCTs and its correlation with clinical features, pathological characteristics, and clinical outcomes. Forty formalin-fixed paraffin-embedded cMCT tissues collected from forty dogs were diagnosed as low-grade (n = 20) or high-grade s(n = 20) MCT according to the Kiupel grading system. The expression level of YKL-40 in cMCT tissues was investigated using immunohistochemical staining and immunoreactivity score (IRS).ResultsYKL-40 was expressed in all cMCTs at different levels, with significantly stronger expression in low-grade cMCTs compared to high-grade cMCTs. The expression level was also associated with tumor diameter, histological grade, mitotic counts, vessel density, and survival of cMCTs. The overall survival of cMCT dogs showed significant differences (p < 0.01) among mild (n = 15, MST 219 days), moderate (n = 19, MST not reached), and high (n = 6, MST not reached) YKL-40 expression groups. Among low-grade cMCTs, overall survival was significantly different between mild YKL-40 expression (MST 319 days) and moderate to high YKL-40 (MST not reached) expression (p < 0.01). In high-grade cMCTs, overall survival was not correlated with YKL-40 expression (p = 0.6589).ConclusionsThis study found that the YKL-40 expression level was significantly stronger in low-grade than in high-grade canine cutaneous mast cell tumors and was associated with various clinical and pathological features. Stronger YKL-40 expression level correlated with longer survival time, especially in low-grade cMCTs. Therefore, YKL-40 could serve as a prognostic marker for cMCTs.

Left Ventricular Apical Aneurysm in a Dog—A Case Report

The cadaver of a 16-year-old mixed-breed male dog was presented to the Faculty of Veterinary Medicine of IULS, Romania, after having been euthanized in a private practice at the owner’s request following acute cardio-respiratory failure. The necropsy revealed a left ventricular apical aneurysm with a bulging fibrous sac measuring about 0.7 cm/0.3 cm. The lesion involved all three structures of the cardiac wall, with mineralization areas and neovascularization. Immunohistochemistry showed strong positivity for desmin and weak positivity for CD-31 in the cardiac muscle fibers, positivity for α-sma in the smooth muscle cells of the vascular walls and positivity for vimentin in the cardiac stroma. MMP-2 and MMP-9 showed strong expression in the cardiomyocytes, whereas TIMP-1 showed positive immunoexpression only in the Eberth’s lines. To the authors’ knowledge, left ventricular apical aneurysm has only been reported once in dogs.

Development of a Disease Modeling Framework for Glutamatergic Neurons Derived from Neuroblastoma Cells in 3D Microarrays

Neurodegenerative diseases (NDDs) present significant challenges due to limited treatment options, ethical concerns surrounding traditional animal models, and the time-consuming and costly process of using human-induced pluripotent stem cells (iPSCs). We addressed these issues by developing a 3D culture protocol for differentiating SH-SY5Y cells into glutamatergic neurons, enhancing physiological relevance with a 3D microarray culture plate. Our protocol optimized serum concentration and incorporated retinoic acid (RA) to improve differentiation. We analyzed the proportions of N-type and S-type cells, observing that RA in the maturation stage not only reduced cell proliferation but also enhanced the expression of MAP2 and VGLUT1, indicating effective neuronal differentiation. Our approach demonstrates the strong expression of glutamatergic neuron phenotypes in 3D SH-SY5Y neural spheroids, offering a promising tool for high-throughput NDD modeling and advancing drug discovery and therapeutic development. This method overcomes limitations associated with conventional 2D cultures and animal models, providing a more effective platform for NDD research.

Outcome of SARS-CoV-2 reinfection depends on genetic background in female mice

Antigenically distinct SARS-CoV-2 variants increase the reinfection risk for vaccinated and previously exposed population due to antibody neutralization escape. COVID-19 severity depends on many variables, including host immune responses, which differ depending on genetic predisposition. To address this, we perform immune profiling of female mice with different genetic backgrounds –transgenic K18-hACE2 and wild-type 129S1– infected with the severe B.1.351, 30 days after exposure to the milder BA.1 or severe H1N1. Prior BA.1 infection protects against B.1.351-induced morbidity in K18-hACE2 but aggravates disease in 129S1. H1N1 protects against B.1.351-induced morbidity only in 129S1. Enhanced severity in B.1.351 re-infected 129S1 is characterized by an increase of IL-10, IL-1β, IL-18 and IFN-γ, while in K18-hACE2 the cytokine profile resembles naïve mice undergoing their first viral infection. Enhanced pathology during 129S1 reinfection cannot be attributed to weaker adaptive immune responses to BA.1. Infection with BA.1 causes long-term differential remodeling and transcriptional changes in the bronchioalveolar CD11c+ compartment. K18-hACE2 CD11c+ cells show a strong antiviral defense expression profile whereas 129S1 CD11c+ cells present a more pro-inflammatory response upon restimulation. In conclusion, BA.1 induces cross-reactive adaptive immune responses in K18-hACE2 and 129S1, but reinfection outcome correlates with differential CD11c+ cells responses in the alveolar space.

Single-cell spatial mapping reveals alteration of cell type composition and tissue microenvironment during early colorectal cancer formation.

Colorectal cancer (CRC) is the third leading cause of cancer mortality in the United States. Familial adenomatous polyposis (FAP) is a hereditary syndrome that raises the risk of developing CRC, with total colectomy as the only effective prevention. Even though FAP is rare (0.5% of all CRC cases), this disease model is well suited for studying the early stages of malignant transformation as patients form many polyps reflective of pre-cancer states. In order to spatially profile and analyze the pre-cancer and tumor microenvironment, we have performed single-cell multiplexed imaging for 52 samples: 12 normal mucosa,16 FAP mucosa,18 FAP polyps, 2 FAP adenocarcinoma, and 4 sporadic colorectal cancer (CRCs) using Co-detection by Indexing (CODEX) imaging platform. The data revealed significant changes in cell type composition occurring in early stage polyps and during the malignant transformation of polyps to CRC. We observe a decrease in CD4+/CD8+ T cell ratio and M1/M2 macrophage ratio along the FAP disease continuum. Advanced dysplastic polyps show a higher population of cancer associated fibroblasts (CAFs), which likely alter the pre-cancer microenvironment. Within polyps and CRCs, we observe strong nuclear expression of beta-catenin and higher number neo-angiogenesis events, unlike FAP mucosa and normal colon counterparts. We identify an increase in cancer stem cells (CSCs) within the glandular crypts of the FAP polyps and also detect Tregs, tumor associated macrophages (TAMs) and vascular endothelial cells supporting CSC survival and proliferation. We detect a potential immunosuppressive microenvironment within the tumor 'nest' of FAP adenocarcinoma samples, where tumor cells tend to segregate and remain distant from the invading immune cells. TAMs were found to infiltrate the tumor area, along with angiogenesis and tumor proliferation. CAFs were found to be enriched near the inflammatory region within polyps and CRCs and may have several roles in supporting tumor growth. Neighborhood analyses between adjacent FAP mucosa and FAP polyps show significant differences in spatial location of cells based on functionality. For example, in FAP mucosa, naive CD4+ T cells alone tend to localize near the fibroblast within the stromal compartment. However, in FAP polyp, CD4+T cells colocalize with the macrophages for T cell activation. Our data are expected to serve as a useful resource for understanding the early stages of neogenesis and the pre-cancer microenvironment, which may benefit early detection, therapeutic intervention and future prevention.

Conventional (bone-type) giant cell tumor of the larynx: the first case with proven H3-3A: c.103G >T (p.Gly35Trp) mutation.

This report documents the first case of a conventional (bone-type) giant cell tumor of the larynx, in which the diagnosis was confirmed by molecular genetic analysis. A 50-year-old non-smoking man experienced progressive hoarseness lasting for 3 months. Imaging showed a 40-mm tumor arising from the right thyroid cartilage. The total laryngectomy was performed. Grossly, the tumor was solid and whitish, with areas of hemorrhage. Microscopically, the tumor consisted of a biphasic population with mononuclear cells with round to oval nuclei, small nucleoli, and pale eosinophilic cytoplasm admixed with evenly distributed dispersed osteoclast-like giant cells. Immunohistochemically, the neoplastic mononuclear cells expressed diffusely vimentin and p63 and focally SATB2. Admixed mononuclear histiocytes coexpressed CD68 and CD163, while the osteoclast-like giant cells showed only CD68 expression. Most importantly, all mononuclear tumor cells showed strong nuclear expression of anti-histone H3.3 G34W antibody. Subsequent next-generation sequencing confirmed the missense mutation of gene H3-3A: c.103G>T (p.Gly35Trp).

Anti-leukemia efficacy of the dual BCL2/BCL-XL inhibitor AZD0466 in acute lymphoblastic leukemia preclinical models

The upregulation of BCL2 and BCL-XL, two proteins in the BCL2 family of proteins, leads to a disproportional expression of pro-death and pro-survival proteins in favor of leukemia survival, tumorigenesis, and chemoresistance. In different subsets of acute lymphoblastic leukemia (ALL), the proportion of these two proteins varies, and their potential as therapeutic targets needs detailed characterization. Here, we investigated BCL2 and BCL-XL, the genes that encode BCL2 and BCL-XL, and their expression differences between B-cell acute lymphoblastic leukemia (B-ALL) and T-cell ALL (T-ALL). We also evaluated the therapeutic potential of targeting these proteins with AZD0466, a novel drug-dendrimer conjugate of the BCL2/-XL inhibitor AZD4320, and with BCL2 inhibitor venetoclax (ABT-199). Gene expression and activity analyses supported by the protein expression patterns in ALL cell lines and primary samples demonstrated increased levels of BCL2 expression in B-ALL with high sensitivity to venetoclax or AZD4320. In contrast, strong BCL-XL expression and sensitivity to dual BCL2/-XL inhibition was observed specifically in T-ALL samples. This observation was confirmed by BH3 profiling, demonstrating BCL2/-XL co-dependence in T-ALL and BCL2 dependence in B-ALL. In a mouse model of T-ALL, AZD0466 but not venetoclax reduced leukemic burden and prolonged survival without significant toxicities. Our findings therefore suggest that the novel dual BCL2/-XL inhibitor AZD0466 outperforms single BCL2 inhibition by venetoclax in T-ALL. These findings facilitate the translation of dual BCL2/-XL inhibitors into ALL clinical trials, either alone or in combination with standard- of- care chemotherapy and immune therapies.

Baseline 18F FDG PET/CT imaging in NSCLC: Possible utility in predicting strong-positive PD-L1 expression

Background/Purpose: To assess whether 18F FDG PET/CT imaging can predict non-small cell lung cancer (NSCLC) patients with strong PD-L1 expression (≥50%). Methods: This retrospective study analyzed 149 NSCLC patients who had undergone baseline 18F FDG PET/CT imaging from June 2021 to May 2024. We recorded age, sex, smoking history, histopathology, TNM stage, metastasis, and PD-L1 expression levels. PET/CT parameters such as SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were recorded. Patients were dichotomized based on two PD-L1 expression thresholds, as measured by immunohistochemistry: higher or lower than 1% (1%, n = 87) and higher or lower than 50% (

The Accessory Olfactory Bulb in Arvicola scherman: A Neuroanatomical Study in a Subterranean Mammal.

The accessory olfactory bulb (AOB) processes chemical signals crucial for species-specific socio-sexual behaviors. There is limited information about the AOB of wild rodents, and this study aims to characterize the neurochemical organization of the AOB in the fossorial water vole (Arvicola scherman), a subterranean Cricetidae rodent. We employed histological, immunohistochemical, and lectin-histochemical techniques. The AOB of these voles exhibits a distinct laminar organization, with prominent mitral cells and a dense population of periglomerular cells. Lectin histochemistry and G-protein immunohistochemistry confirmed the existence of an antero-posterior zonation. Immunohistochemical analysis demonstrated significant expression of PGP 9.5, suggesting its involvement in maintaining neuronal activity within the AOB. In contrast, the absence of SMI-32 labelling in the AOB, compared to its strong expression in the main olfactory bulb, highlights functional distinctions between these two olfactory subsystems. Calcium-binding proteins allowed the characterization of atypical sub-bulbar nuclei topographically related to the AOB. All these features suggest that the AOB of Arvicola scherman is adapted for enhanced processing of chemosensory signals, which may play a pivotal role in its subterranean lifestyle. Our results provide a foundation for future studies exploring the implications of these adaptations, including potential improvements in the management of these vole populations.

Quercetin and its potential therapeutic effects on aluminum phosphide-induced cardiotoxicity in rats: Role of NOX4, FOXO1, ERK1/2, and NF-κB

Acute Aluminum phosphide (AlP) poisoning poses a serious global issue, yet the exact mechanisms behind AlP-induced cardiotoxicity are still not well understood. Moreover, there is no specific antidote available for AlP toxicity. Nevertheless, Quercetin (QE) has emerged as a promising therapeutic candidate in various contexts. Accordingly, our study aimed to evaluate the QE potential therapeutic effects against AlP-induced cardiotoxicity and the mechanisms underlying such effects. Rats were assigned into four groups: Group I (control group), Group II (vehicle (corn oil) group), Group III (AlP group) received a single dose of AlP (10 mg/kg body weight) dissolved in corn oil by oral gavage, and Group IV (AlP + QE group) received a single dose of QE (400 mg/kg body weight) dissolved in saline, one hour after AlP administration. AlP-induced cardiotoxicity was evidenced by the increase in cardiac troponin I (cTnI) as well as the hemodynamic, ECG, and histopathological abnormalities. The AlP group denoted a decrease of the antioxidant enzymes; catalase and SOD and an increase of the lipid peroxidation marker; MDA. This was associated with a notable increase in inflammatory cytokines (TNFα, IL-6, and IL1β), in addition to a significant upregulation of the expression of NOX4, FOXO1, ERK1/2, and NF-κB. Moreover, Caspase3, and BAX showed strong immunopositive expression, while Bcl-2 showed mild immunoexpression. On the other hand, treatment with QE showed an improvement in the cardiotoxic effects of AlP, as indicated by significant enhancements in biomarkers, functional assessments, and histopathological findings. These results suggest that QE may be a promising candidate for treating AlP-induced cardiotoxicity, attributed to its antioxidant, anti-inflammatory, and anti-apoptotic properties, particularly emphasizing the roles of NOX4, FOXO1, ERK1/2, and NF-κB.

Granzyme mRNA-miRNA interaction and its implication to functional impact.

Granzyme activity can affect the processing and stability of miRNAs within target cells. They also could induce changes in miRNA expression that impact apoptotic signaling. Granzyme-induced apoptosis might result in changes to the miRNA profile, which can further influence the apoptosis and inflammation processes. The aim of this study was to bioinformatically analyze which miRNAs and transcription factors bind to the CDS and UTR regions of the granzyme family to regulate gene expression in relation to granzyme evolution and their association with human cancer diseases. The expression patterns of granzyme genes were analyzed in various human tissues. MiRNAs binding to the CDS and UTR of the granzyme family were examined, and the transcription factors binding to these miRNAs binding sites were also analyzed. Cytoscape program was used to visualize and analyze the networks of interactions between granzyme mRNA and miRNAs. Additionally, the evolutionary patterns of the granzyme family in relation to miRNAs and transcription factors binding were investigated. Analysis of the expression patterns of the granzyme family in various human tissues shows that GZMA and GZMK are strongly expressed in lymph nodes. GZMB exhibits strong expression in the bone marrow, while GZMA is prominently expressed in the spleen. Twenty-two miRNAs bind to both GZMK and GZMB mRNA, while six miRNAs bind to both GZMK and GZMM mRNA. The only miRNA that binds to GZMK, GZMB, GZMM, and GZMA mRNA is hsa-miR-146a-5p. Transcription factors JUND, FOS, and JUN are distinctly interconnected with has-miR-5696 and GZMK. Association data between the granzyme family and cancers showed that various miRNAs were consistently implicated and exhibited either upregulation or downregulation. Although the granzyme family possesses distinct genetic information, it shows relatively high expression levels in the lymph node, spleen, and bone marrow. Many miRNAs specifically regulate granzyme gene expression, and various transcription factors are involved. Analyzing the granzyme genes-miRNAs-transcription factors-related network will provide crucial insights into the mechanisms of cancer development and suppression.

Correlation between CTNNB1 mutation status and tumour phenotype in hepatitis B virus-related hepatocellular carcinoma.

The frequency of CTNNB1 mutation, one of the most frequent genetic events in hepatocellular carcinoma (HCC), is lower in Asian countries and in hepatitis B virus (HBV)-related HCCs. In this study, we evaluated the prevalence and types of CTNNB1-mutation in HBV-related HCC and correlated the molecular status with the histomorphological and immunohistochemical features. A total of 108 consecutive cases of treatment-naïve, surgically resected HBV-related HCCs were selected. Targeted sequencing for CTNNB1 exons 3, 7 and 8 was performed, and the results were correlated with the expression pattern of glutamine synthetase (GS), nuclear β-catenin expression status and the histomorphological characteristics of the tumour. CTNNB1 mutations were identified in 13% of HBV-related HCCs; of these cases, mutations were found in D32-S37 (7%), T41 (4%) and S45 (2%) of exon 3. None of the HCCs demonstrated alterations in exons 7 and 8. CTNNB1 mutation was strongly associated with diffuse strong GS expression (P < 0.001), nuclear β-catenin expression (P < 0.001) and the classic CTNNB1 morphology (P = 0.038). Diffuse strong GS expression was observed in 78.6% of the CTNNB1-mutated HCCs, and nuclear β-catenin expression was identified in 64.3% of these cases. The classic CTNNB1 morphology was observed in 57% of all CTNNB1-mutated HCCs. Furthermore, programmed death-ligand 1 (PD-L1) was less frequently expressed in HCCs with classic CTNNB1 morphology. CTNNB1 mutation was observed in 13% of HBV-related HCCs in this Korean cohort, and was associated with diffuse strong GS expression, nuclear β-catenin expression and classic CTNNB1 morphology.

Detection of molecular markers of ferroptosis in human Alzheimer's disease brains.

We have previously shown that droplet degeneration (DD) signifies the beginning of neuritic plaque formation during Alzheimer's disease (AD) pathogenesis. As microglia associated with neuritic plaques exhibited strong ferritin expression and Perl's iron staining showed iron in microglia, droplet spheres and neuritic plaque cores, we hypothesized that DD is a form of ferroptosis. Detection of molecular markers of ferroptosis in AD brains. Immunohistochemical detection of transferrin receptor (TfR) and ferritin as ferroptosis markers in prefrontal cortex of AD brains, investigation of spatial correlation of these with histopathological hallmarks of AD, visualization of ferroptotic marker genes by in situ hybridization, comparison of expression of ferroptosis genes with snRNAseq analyses and comparison of TfR and ferritin expression in different neurofibrillary tangle (NFT) stages. TfR was found on neurons that appeared to be degenerating and exhibited typical features of droplet degeneration. Co-localization with hyperphosphorylated tau (p-tau) was a rare event. TfR-positive neurons increased with higher NFT stages as did ferritin expression in microglia. mRNA of genes linked to ferroptosis was detected in pretangles and p-tau negative neurons, less in DD. snRNAseq analyses support a link between AD, ferroptosis and TfR as a ferroptosis marker. Increased expression of TfR and ferritin in high NFT stages, demonstration of ferroptotic marker genes in Alzheimer's lesions, as well as snRNAseq analyses strengthen our hypothesis that DD represents ferroptosis. Because of the morphological similarity between TfR-positive structures and DD, TfR might be an early ferroptosis marker expressed transiently during AD pathogenesis.

PATH-35. INTEGRATED GENOMIC ANALYSES OF IMMUNODEFICIENCY-ASSOCIATED EPSTEIN-BARR VIRUS- (EBV) POSITIVE PRIMARY CNS LYMPHOMAS

Abstract Immunodeficiency-associated primary CNS lymphoma (PCNSL) represents a distinct clinicopathological entity, which is typically Epstein-Barr virus positive (EBV+) and carries an inferior prognosis. Genetic alterations that characterize EBV related CNS lymphomagenesis remain unclear precluding molecular classification and targeted therapies. In this study, a comprehensive genetic analysis of 22 EBV+ PCNSL, integrated clinical and pathological information with exome and RNA sequencing (RNASeq) data. Deconvolution of bulk RNA sequencing data was performed using CIBERSORTx to characterize the tumor microenvironment. EBV+ PCNSL with germline controls carried a median of 55 protein-coding single nucleotide variants (SNVs; range 24-217) and 2 insertions/deletions (range 0-22). Genetic landscape was largely shaped by aberrant somatic hypermutation with a median of 41.01% (range 31.79-53.49%) of SNVs mapping to its target motifs. Tumors lacked established SNVs (MYD88, CD79B, PIM1) and copy number variants (CDKN2A, HLA loss) driving EBV negative PCNSL. Instead, EBV+ PCNSL were characterized by SOCS1 mutations (26%), predicted to disinhibit JAK/STAT signaling, and mutually exclusive gain-of-function NOTCH pathway SNVs (26%). Copy number gains were enriched on 11q23.3, a locus directly targeted for chromosomal aberrations by EBV, that includes SIK3 known to protect from cytotoxic T-cell responses. Losses covered 5q31.2 (STING), critical for sensing viral DNA, and 17q11 (NF1). Unsupervised clustering of RNASeq data revealed two distinct transcriptional groups, that shared strong expression of CD70 and IL1R2, previously linked to tolerogenic tumor microenvironments. Correspondingly, deconvolution of bulk RNASeq data revealed elevated M2-macrophage, T-regulatory cell, mast cell and monocyte fractions in EBV+ PCNSL. In addition to novel insights into the pathobiology of EBV+ PCNSL, the data provide the rationale for the exploration of targeted therapies including JAK-, NOTCH- and CD70-directed approaches.

Histone H3K9 Methylation Is Differentially Modified in Odontogenic Cyst and Tumors.

Histone modification in odontogenic lesions is mostly unexplored. Trimethylation of histone H3 at lysine residue 9 (H3K9Me3) has been studied in various pathologic conditions and showed biological significance promising for future therapeutic application. This study aimed to investigate the level and clinical relevance of the H3K9Me3 histone modification in odontogenic cysts and tumors. A total of 105 cases of odontogenic lesions, comprising 30 odontogenic keratocysts (OKCs), 30 adenomatoid odontogenic tumors (AOTs), 30 ameloblastomas, and 15 dental follicles, were included in the study. The paraffin-embedded tissues were immunohistochemically stained for H3K9Me3. Both the intensity and the distribution of staining were evaluated and calculated as H-score. The correlation between the H3K9Me3 expression and the clinical characteristics of each lesion was evaluated. The Kruskal-Wallis test followed by Bonferroni's correction was performed to assess the differences in H-score among groups. In addition, Pearson's chi-squared test or Mann-Whitney U test was used to analyze potential factors that could affect protein expression. The reduced enamel epithelium of the dental follicle showed uniformly strong H3K9Me3 expression. All odontogenic cysts and tumors examined demonstrated a significantly reduced H3K9Me3 level compared with dental follicles. The AOT showed the lowest H3K9Me3 level, followed by OKC and ameloblastoma. Its immunoreactivity was mainly localized in the basal and parabasal cells of OKC and the whorled/duct-like structures of AOT. Ameloblastoma exhibited marked variation in the H3K9Me3 level among cases. Notably, the upregulated H3K9Me3 was related to multilocularity of OKC and ameloblastoma. Histone H3K9 methylation is differentially expressed in odontogenic cysts and tumors. This epigenetic modification may contribute to the pathogenesis and aggressive behavior of odontogenic lesions.

Cartilage extracellular matrix collagen type II and aggrecan expressions in rabbit cartilage following mesenchymal stem cell implantation

Collagen II and aggrecan are the major components of the cartilage extracellular matrix (ECM) that determine the structure and function of the hyaline articular cartilage. Therefore, their examination should be included in the evaluation of the repair tissue, which is formatted into osteochondral defects (ODs). In this study, the effect of allogeneic-derived stem cells (DSCs), including bone marrow-DSCs (BMDSCs), adipose-DSCs (ADSCs), and synovial membrane-DSCs (SMDSCs), implantation on collagen II and aggrecan production was evaluated. Forty-eight New Zealand rabbits underwent the creation of 3×3mm sized ODs in the femoral patellar groove on both knees and were then randomly assigned to three groups. In all groups, the ODs in the right limbs were filled with fibrin glue (FG), whereas the ODs in the left limbs were filled with ADSCs+FG in group A, with BMDSCs+FG in group B and with SMDSCs+FG in group C. After 12 weeks the repair tissues were immunohistologically assessed for collagen II and aggrecan. Accordingly, FG and ADCSs (p=0.003), BMDSCs (p=0.017), and SMDSCs (p=0.003) implantation resulted in significantly stronger expression of collagen II in the reparative tissue compared with the FG groups. Also, the newly formed tissue in the BMDSCs+FG (p=0.015) and SMDSCs+FG (p=0.003) groups expressed significantly higher aggrecan compared with the FG groups, whereas BMDSCs+FG (p=0.030) and SMDSCs+FG (p=0.002) transplantation promoted significantly higher aggrecan composition compared with ADSCs+FG. These findings indicate the profound impact of BMDSCs and SMDSCs on the ECM quality of the repair tissue. Additionally, the inefficiency of FG to induce a well-developed ECM in the repair area was highlighted.