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Biochimica Et Biophysica Acta.... Jun 2024Toll-like receptor 9 (Tlr9) is a pathogen recognition receptor detecting unmethylated DNA derivatives of pathogens and damaged host cells. It is therefore an important...
BACKGROUND & AIMS
Toll-like receptor 9 (Tlr9) is a pathogen recognition receptor detecting unmethylated DNA derivatives of pathogens and damaged host cells. It is therefore an important modulator of innate immunity. Here we investigated the role of Tlr9 in fibrogenesis and progression of hepatocellular carcinoma in chronic liver disease.
MATERIALS AND METHODS
We treated mice with a constitutive deletion of Tlr9 (Tlr9) with DEN/CCl for 24 weeks. As a second model, we used hepatocyte-specific Nemo knockout (Nemo) mice and generated double knockout (NemoTlr9) animals.
RESULTS
We show that Tlr9 is in the liver primarily expressed in Kupffer cells, suggesting a key role of Tlr9 in intercellular communication during hepatic injury. Tlr9 deletion resulted in reduced liver fibrosis as well as tumor burden. We observed down-regulation of hepatic stellate cell activation and consequently decreased collagen production in both models. Tlr9 deletion was associated with decreased apoptosis and compensatory proliferation of hepatocytes, modulating the initiation and progression of hepatocarcinogenesis. These findings were accompanied by a decrease in interferon-β and an increase in chemokines having an anti-tumoral effect.
CONCLUSIONS
Our data define Tlr9 as an important receptor involved in fibrogenesis, but also in the initiation and progression of hepatocellular carcinoma during chronic liver diseases.
PubMed: 38943920
DOI: 10.1016/j.bbadis.2024.167321 -
ESMO Open Jun 2024The characterization and comparison of gene expression and intrinsic subtype (IS) changes induced by neoadjuvant chemotherapy (NACT) and endocrine therapy in hormone...
Unraveling the clinicopathological and molecular changes induced by neoadjuvant chemotherapy and endocrine therapy in hormone receptor-positive/HER2-low and HER2-0 breast cancer.
BACKGROUND
The characterization and comparison of gene expression and intrinsic subtype (IS) changes induced by neoadjuvant chemotherapy (NACT) and endocrine therapy in hormone receptor-positive (HR+)/human epidermal growth factor receptor 2 (HER2)-low versus HR+/HER2-0 breast cancer (BC) has not been conducted so far. Most evidence on the association of HER2 status with pathologic responses and prognosis in HR+/HER2-negative BC is controversial and restricted to NACT-treated disease. Similarly, a temporal heterogeneity in HER2 status has been described only with NACT.
METHODS
We retrospectively recruited a consecutive cohort of 186 patients with stage I-IIIB HR+/HER2-negative BC treated with neoadjuvant therapy (NAT). Available diagnostic biopsies and surgical samples were characterized for main pathological features, PAM50 IS and ROR-P score, and gene expression. Associations with pathologic complete response, residual cancer burden-0/I, event-free survival (EFS) and overall survival (OS) based on HER2 status were assessed. Pre/post pathologic/molecular changes were analyzed in matched samples.
RESULTS
The HER2-low (62.9%) and HER2-0 (37.1%) cohorts did not differ significantly in main baseline features, treatments administered, breast-conserving surgery, pathologic complete response and residual cancer burden-0/I rates, EFS, and OS. NAT induced, regardless of HER2 status, a significant reduction of estrogen receptor/progesterone receptor and Ki67 levels, a down-regulation of PAM50 proliferation- and luminal-related genes/signatures, an up-regulation of selected immune genes, and a shift towards less aggressive IS and lower ROR-P. Moreover, 25% of HER2-0 changed to HER2-low and 34% HER2-low became HER2-0. HER2 shifts were significant after NACT (P < 0.001), not neoadjuvant endocrine therapy (P = 0.063), with consistent ERBB2 mRNA level dynamics. HER2 changes were not associated with EFS/OS.
CONCLUSIONS
HER2-low and HER2-0 status change after NAT in ∼30% of cases, mostly after NACT. Targeted adjuvant strategies should be investigated accordingly. Molecular downstaging with current chemo/endocrine agents and immunotherapy should not rely on HER2 immunohistochemical levels in HR+/HER2-negative BC. Instead, HER2-low-targeted approaches should be explored to pursue more effective and/or less toxic dimensional downstaging.
PubMed: 38943737
DOI: 10.1016/j.esmoop.2024.103619 -
EBioMedicine Jun 2024
PubMed: 38943726
DOI: 10.1016/j.ebiom.2024.105224 -
Molecular Therapy : the Journal of the... Jun 2024NK cells eliminate infected or cancer cells via their cytotoxic capacity. NKG2A is an inhibitory receptor on NK cells and cancer cells often overexpress its ligand HLA-E...
NK cells eliminate infected or cancer cells via their cytotoxic capacity. NKG2A is an inhibitory receptor on NK cells and cancer cells often overexpress its ligand HLA-E to evade NK cell surveillance. Given the successes of immune checkpoint blockade in cancer therapy, NKG2A is an interesting novel target. However, anti-NKG2A antibodies have shown limited clinical response. In the pursuit of enhancing NK cell-mediated anti-tumor responses, we devised a Cas9-based strategy to delete KLRC1, encoding NKG2A, in human primary NK cells. Our approach involved electroporation of KLRC1-targeting Cas9-ribonucleoprotein resulting in effective ablation of NKG2A expression. Compared to anti-NKG2A antibody blockade, NKG2A-knockout NK cells exhibited enhanced activation, reduced suppressive signaling, and elevated expression of key transcription factors. NKG2A-deficient NK cells overcame inhibition from HLA-E, significantly boosting NK cell activity against solid and hematologic cancer cells. We validated this efficacy across multiple cell lines, a xenograft mouse model, and primary human leukemic cells. Combining NKG2A knockout with antibody-coating of tumor cells further enhanced cytotoxicity through ADCC. Thus, we provide a comprehensive comparison of inhibition of the NKG2A pathway using genetic ablation and antibodies and provide novel insight in the observed differences molecular mechanisms, which can be translated to enhance adoptive NK cell immunotherapy.
PubMed: 38943249
DOI: 10.1016/j.ymthe.2024.06.034 -
BMC Pharmacology & Toxicology Jun 2024Chalcones and dihydrochalcones (DHCs) are important bioactive natural products (BNPs) isolated from traditional Chinese medicine. In this study, 13 chalcones were...
Chalcones and dihydrochalcones (DHCs) are important bioactive natural products (BNPs) isolated from traditional Chinese medicine. In this study, 13 chalcones were designed with the inspiration of Loureirin, a DHC extracted from Resina Draconis, and synthesized by classical Claisen-Schmidt reactions. Afterwards the reduction reactions were carried out to obtain the corresponding DHCs. Cytotoxicity assay indicated chalcones and DHCs possessed selective cytotoxicity against colorectal cancer (CRC) cells. The preliminary structure-activity relationships (SAR) of these compounds suggested the α, β-unsaturated ketone of the chalcones were crucial for the anticancer activity. Interestingly, compounds 3d and 4c exhibited selective anticancer activity against CRC cell line HCT116 with IC of 8.4 and 17.9 μM but not normal cell. Moreover, 4c could also inhibit the migration and invasion of CRC cells. Mechanism investigations showed 4c could induce cell cycle G2/M arrest by regulating cell cycle-associated proteins and could also up-regulate Fas cell surface death receptor. The virtual docking further pointed out that compounds 3d and 4c could nicely bind to the Fas/FADD death domain complex (ID: 3EZQ). Furthermore, silencing of Fas significantly enhanced the proliferation of CRC cells and attenuated the cytotoxicity induced by 4c. These results suggested 4c exerted its anticancer activity possibly regulating cell cycle and Fas death receptor. In summary, this study investigated the anticancer activity and mechanism of Loureirin analogues in CRC, suggesting these compounds may warrant further investigation as promising anticancer drug candidates for the treatment of CRC.
Topics: Humans; Colorectal Neoplasms; Chalcones; Antineoplastic Agents; fas Receptor; Structure-Activity Relationship; HCT116 Cells; Molecular Docking Simulation; Cell Movement; Cell Cycle; Cell Line, Tumor
PubMed: 38943212
DOI: 10.1186/s40360-024-00758-2 -
Alzheimer's Research & Therapy Jun 2024Amyloid-β (Aβ) and tau are brain hallmarks of Alzheimer's disease (AD), also present in blood as soluble biomarkers or encapsulated in extracellular vesicles (EVs).... (Comparative Study)
Comparative Study
BACKGROUND
Amyloid-β (Aβ) and tau are brain hallmarks of Alzheimer's disease (AD), also present in blood as soluble biomarkers or encapsulated in extracellular vesicles (EVs). Our goal was to assess how soluble plasma biomarkers of AD pathology correlate with the number and content of EVs.
METHODS
Single-molecule enzyme-linked assays were used to quantify Aβ42/40 and tau in plasma samples and neurally-derived EVs (NDEVs) from a cohort of APOE ε4- (n = 168) and APOE ε4+ (n = 68) cognitively normal individuals and AD patients (n = 55). The ratio of CD56 (Neuronal cell-adhesion molecule) to CD81 signal measured by ELISA-DELFIA was used for the relative quantification of NDEVs in plasma samples.
RESULTS
The soluble plasma Aβ42/40 ratio is decreased in AD patients compared to cognitively normal individuals. The amount and content (Aβ40, Aβ42, tau) of plasma NDEVs were similar between groups. Plasma NDEVs quantity remain consistent with aging and between AD and CN individuals. However, the quantity of soluble biomarkers was negatively correlated to NDEVs number in cognitively normal individuals, while in AD patients, this correlation is lost, suggesting a shift in the mechanism underpinning the production and the release of these biomarkers in pathological conditions.
CONCLUSION
Soluble plasma Aβ42/40 ratio is the most robust biomarker to discriminate between AD patients and CN individuals, as it normalizes for the number of NDEVs. Analysis of NDEVs and their content pointed toward peculiar mechanisms of Aβ release in AD. Further research on independent cohorts can confirm our findings and assess whether plasma Aβ and tau need correction by NDEVs for better AD risk identification in CN populations.
Topics: Humans; Alzheimer Disease; Extracellular Vesicles; Biomarkers; Female; Male; Amyloid beta-Peptides; Aged; tau Proteins; Peptide Fragments; Aged, 80 and over; Middle Aged; Cohort Studies; Apolipoprotein E4
PubMed: 38943196
DOI: 10.1186/s13195-024-01508-6 -
Cell Communication and Signaling : CCS Jun 2024Liver sinusoidal endothelial cells (LSECs) are highly specialized endothelial cells that represent the interface between blood cells on one side and hepatocytes on the... (Review)
Review
Liver sinusoidal endothelial cells (LSECs) are highly specialized endothelial cells that represent the interface between blood cells on one side and hepatocytes on the other side. LSECs not only form a barrier within the hepatic sinus, but also play important physiological functions such as regulating hepatic vascular pressure, anti-inflammatory and anti-fibrotic. Pathologically, pathogenic factors can induce LSECs capillarization, that is, loss of fenestra and dysfunction, which are conducive to early steatosis, lay the foundation for the progression of metabolic dysfunction-associated fatty liver disease (MAFLD), and accelerate metabolic dysfunction-associated steatohepatitis (MASH) and liver fibrosis. The unique localization, phenotype, and function of LSECs make them potential candidates for reducing liver injury, inflammation, and preventing or reversing fibrosis in the future.
Topics: Humans; Endothelial Cells; Animals; Liver; Fatty Liver; Liver Cirrhosis
PubMed: 38943171
DOI: 10.1186/s12964-024-01720-9 -
Scientific Reports Jun 2024Breast cancer is a prevalent and significant cause of mortality in women, and manifests as six molecular subtypes. Its further histologic classification into...
Breast cancer is a prevalent and significant cause of mortality in women, and manifests as six molecular subtypes. Its further histologic classification into non-invasive ductal or lobular carcinoma (DCIS) and invasive carcinoma (ILC or IDC) underscores its heterogeneity. The ubiquitin-proteasome system plays a crucial role in breast cancer, with inhibitors targeting the 26S proteasome showing promise in clinical treatment. The Cullin-RING ubiquitin ligases, including CUL3, have direct links to breast cancer. This study focuses on CUL3 as a potential biomarker, leveraging high-throughput sequencing, gene expression profiling, experimental and data analysis tools. Through comprehensive analysis using databases like GEPIA2 and UALCAN, as well as TCGA datasets, CUL3's expression and its association with prognostic values were assessed. Additionally, the impact of CUL3 overexpression was explored in MCF-7 and MDA-MB-231 breast cancer cell lines, revealing distinct differences in molecular and phenotypic characteristics. We further profiled its expression and localization in breast cancer tissues identifying prominent differences between luminal A and TNBC tumors. Conclusively, CUL3 was found to be associated with cell cycle progression, and DNA damage response, exhibiting diverse roles depending on the tumor's molecular type. It exhibits a tendency to act as an oncogene in triple-negative tumors and as a tumor suppressor in luminal A types, suggesting a potential significance in breast cancer progression and therapeutic directions.
Topics: Humans; Cullin Proteins; Female; Prognosis; Breast Neoplasms; Biomarkers, Tumor; Gene Expression Regulation, Neoplastic; Cell Line, Tumor; Gene Expression Profiling; MCF-7 Cells; Triple Negative Breast Neoplasms
PubMed: 38942922
DOI: 10.1038/s41598-024-65692-z -
Cell Death & Disease Jun 2024Lung cancer stands as the leading cause of mortality among all types of tumors, with over 40% of cases being lung adenocarcinoma (LUAD). Family with sequence similarity...
Lung cancer stands as the leading cause of mortality among all types of tumors, with over 40% of cases being lung adenocarcinoma (LUAD). Family with sequence similarity 83 member A (FAM83A) emerges as a notable focus due to its frequent overexpression in LUAD. Despite this, the precise role of FAM83A remains elusive. This study addresses this gap by unveiling the crucial involvement of FAM83A in maintaining the cancer stem cell-like (CSC-like) phenotype of LUAD. Through a global proteomics analysis, the study identifies human epidermal growth factor receptor 2 (HER2 or ErbB2) as a crucial target of FAM83A. Mechanistically, FAM83A facilitated ErbB2 expression at the posttranslational modification level via the E3 ubiquitin ligase STUB1 (STIP1-homologous U-Box containing protein 1). More importantly, the interaction between FAM83A and ErbB2 at Arg241 promotes calcineurin (CALN)-mediated dephosphorylation of ErbB2, followed by inhibition of STUB1-mediated ubiquitin-proteasomal ErbB2 degradation. The maintenance of the CSC-like phenotype by FAM83A, achieved through the posttranslational regulation of ErbB2, offers valuable insights for identifying potential therapeutic targets for LUAD.
Topics: Humans; Receptor, ErbB-2; Adenocarcinoma of Lung; Lung Neoplasms; Neoplastic Stem Cells; Neoplasm Proteins; Phenotype; Animals; Mice; Cell Line, Tumor; Ubiquitin-Protein Ligases
PubMed: 38942760
DOI: 10.1038/s41419-024-06853-w -
Journal of Oral Biosciences Jun 2024This study aimed to investigate the regulatory mechanisms governing dental mesenchymal cell commitment during tooth development, focusing on odontoblast differentiation...
Exploring the Role of DNMT1 in Dental Papilla Cell Fate Specification during Mouse Tooth Germ Development through Integrated Single-Cell Transcriptomics and Bulk RNA Sequencing.
OBJECTIVES
This study aimed to investigate the regulatory mechanisms governing dental mesenchymal cell commitment during tooth development, focusing on odontoblast differentiation and the role of epigenetic regulation in this process.
METHODS
We performed single-cell RNA sequencing (scRNA-seq) of dental cells from embryonic day 14.5 (E14.5) mice to understand the heterogeneity of developing tooth germ cells. Computational analyses including gene regulatory network (GRN) assessment were conducted. We validated our findings using immunohistochemistry (IHC) and in vitro loss-of-function analyses using the DNA methyltransferase 1 (DNMT1) inhibitor Gsk-3484862 in primary dental mesenchymal cells (DMCs) isolated from E14.5 mouse tooth germs. Bulk RNA-seq of Gsk-3484862-treated DMCs was performed to identify potential downstream targets of DNMT1.
RESULTS
scRNA-seq analysis revealed diverse cell populations within the tooth germs, including epithelial, mesenchymal, immune, and muscle cells. Using single-cell regulatory network inference and clustering (SCENIC), we identified Dnmt1 as a key regulator of early odontoblast development. IHC analysis showed the ubiquitous expression of DNMT1 in the dental papilla and epithelium. Bulk RNA-seq of cultured DMCs showed that Gsk-3484862 treatment upregulated odontoblast-related genes, whereas genes associated with cell division and the cell cycle were downregulated. Integrated analysis of bulk RNA-seq data with scRNA-seq SCENIC profiles was used to identify the potential Dnmt1 target genes.
CONCLUSIONS
Dnmt1 may negatively affect odontoblast commitment and differentiation during tooth development. These findings contribute to a better understanding of the molecular mechanisms underlying tooth development and future development of hard-tissue regenerative therapies.
PubMed: 38942194
DOI: 10.1016/j.job.2024.06.010