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Human alpha-herpesvirus 1 (HSV-1) acute infection culminates in life-long latency in sensory neurons in trigeminal ganglia and certain neurons in the central nervous system. Previously, E2F family members and glucocorticoid receptor (GR) were shown to stimulate HSV-1 and bovine herpesvirus 1 (BoHV-1) replication. Consequently, we hypothesized GR and E2F family members activate certain HSV-l promoters. To test this hypothesis, we determined if four HSV-1 ICP0 cis-regulatory modules (CRM) upstream of the ICP0 promoter were activated by E2F. GR and E2F2, but not E2F1, E2F3a, or E2F3b, cooperatively transactivate the ICP0 CRM-C, but not CRM-A, -B, or -D fragments upstream of a minimal promoter in a luciferase reporter construct. CRM-C sequences contain two E2F consensus binding sites, a GC-rich motif that E2F2 can bind, and a consensus ½ GR response element (GRE) adjacent to the consensus E2F #2 binding site. Mutating the ½ GRE or the 3 E2F binding sites significantly reduced GR- and E2F2-mediated transactivation. Chromatin immunoprecipitation studies revealed E2F2 occupied ICP0 CRM-C sequences during productive infection and mutating the E2F binding sites prevented E2F2 binding. These studies reveal GR and E2F2 transactivate ICP0-promoter activity, which may enhance viral replication in certain cell types.

Tubule-derived pro-fibrotic mediators are central for the development of kidney fibrosis. We previously showed that fibrotic stimuli activate and elevate GEF-H1 (ARHGEF2) in tubular cells, leading to RhoA-dependent fibrotic reprogramming. In search of new mechanisms of GEF-H1 regulation, here we used immunoprecipitation and proximity ligation assay to show interaction between GEF-H1 and Myotonic Dystrophy Kinase-related Cdc42-binding kinase (MRCK)α in tubular cells. MRCKα silencing elevated GEF-H1 activity, and induced GEF-H1-dependent RhoA activation, stress fibre formation and myosin light chain phosphorylation. MRCKα depletion also elevated phospho-cofilin levels in a RhoA-dependent manner. The fibrogenic cytokine TGFβ1 rapidly increased binding between GEF-H1 and MRCKα, while MRCKα silencing augmented TGFβ1-induced GEF-H1 activation, suggesting a negative feedback loop. An mRNA array detecting fibrogenic genes revealed increase in a subset of basal and TGFβ1-induced genes following MRCKα depletion. MRCKα silencing promoted nuclear translocation of the profibrotic transcriptional co-activator Myocardin-Related Transcription Factor (MRTF), and MRTF-A+B depletion prevented increase in ACTA2 (α-smooth muscle actin), a key marker of fibrotic reprogramming. Finally, total MRCKα mRNA was reduced in a murine kidney fibrosis model, and immunohistochemistry revealed a decrease in tubular MRCKα. Taken together, we identified MRCKα as a new suppressor of GEF-H1/RhoA/MRTF signaling. Reduced MRCKα expression in kidney fibrosis may promote tubular fibrotic gene expression.

Due to the application of antiretroviral therapy, HIV has become a manageable chronic disease, and people living with HIV/AIDS (PLWHA) experience several comorbidities, including cardiovascular disease. Although antiretroviral therapy suppresses the viral load to an undetectable level, HIV proteins can still be detected in the circulation and in different organs. In our previous study, we found that the expression of the Nef protein causes cardiac dysfunction and heart failure in a transgenic mouse model. We also observed inhibition of autophagy along with the upregulation of the senescence marker Bcl2. To further understand the metabolic changes related to Nef in cardiac tissue, we examined nicotinamide adenine dinucleotide (NAD) metabolism in the heart. Our metabolic study with cardiac tissue revealed that Nef expression decreases NAD+ levels in the heart. Additionally, we explored whether replenishing cellular NAD+ could be a potential therapeutic target for HIV-associated cardiovascular disease. Interestingly, our study found that NMN treatment can improve cellular autophagy, decrease the senescence marker Bcl2, and reduce fibrosis in the heart. Overall, our study suggests that NMN could serve as a promising therapeutic molecule for the treatment of HIV-associated cardiovascular comorbidities.

The heterogeneity of colorectal cancer (CRC) represents a great challenge in therapy. We integrated multiomics and machine learning, interpreted by SHAP models to provide a clinical rationale, to identify Calcineurin B Homologous Protein 2 (CHP2) as a core candidate, which was further validated via in vitro and zebrafish models. The expression of CHP2 are decreased in CRC, which is associated with a poor prognosis and an immune suppressed "cold" TIME. Functionally, CHP2 overexpression inhibits cell growth and invasion by inducing PANoptosis. Clinically, specific CHP2 expression profiles discriminate patients at high risk that are resistant to standard chemotherapy (e.g., 5-FU) but sensitive to targeted inhibitors. CHP2 is a powerful dual-function biomarker-prognostic for survival and predictive for the response to therapy-that could lead to a personalized approach in treating drug-resistant CRC.

Background/Objectives: B-cell precursor acute lymphoblastic leukemia (B-ALL), the most common pediatric acute leukemia (AL), is frequently characterized by aberrant antigen expression, which aids diagnosis and prognosis. The myeloid antigen CD66c is notably frequent in B-ALL and has been proposed as a marker of disease aggressiveness and treatment response. Evaluating CD66c in Mexican pediatric patients may provide insights into disease biology. Methods: A cohort of 128 pediatric patients was referred to the Laboratory of Oncoimmunology and Cytomics of Childhood Cancer (OCL) at Instituto Mexicano del Seguro Social (IMSS) for immunophenotyping tests between March 2022 and November 2023. Additionally, control bone marrow (BM) samples were assessed. Aberrant antigen expression in hematopoietic populations and BM microenvironment stroma phenotyping were performed. Results: In total, 84.38% of B-ALL patients exhibited aberrant expression of ≥1 myeloid antigen. Among CD66c-positive patients, 13.79% had detectable measurable residual disease (MRD) during follow-up and 20.69% died. Mesenchymal stromal cells (MSCs) from patients with positive or low CD66c expression displayed inflammatory profiles. ProB leukemias with low CD66c expression were more likely to exhibit detectable MRD, increased mortality, and reduced survival. Conclusions: Low CD66c expression induces molecular stealth that could favor immune evasion and niche persistence, thereby increasing the risk of relapse and therapeutic failure.

Chemoresistance remains a major barrier to effective colorectal cancer (CRC) therapy, yet its metabolic underpinnings are poorly defined. Here, we integrate lipidomic profiling, enzymatic analysis, and functional perturbation approaches to elucidate the contribution of phosphatidylcholine (PC) metabolism and its biosynthetic regulator Choline Phosphotransferase 1 (CHPT1) to drug response. Comparative analysis of chemosensitive and chemoresistant CRC cell lines revealed that resistant HT29 cells exhibited significantly higher PC content and altered PC/lysophosphatidylcholine (LPC)ratios relative to sensitive counterparts. Importantly, functional perturbation confirmed causality: CHPT1 overexpression in SW620 cells was sufficient to promote PC accumulation and confer a chemoresistant phenotype. These findings identify CHPT1 as a metabolic gatekeeper of chemoresistance. Consistently, Human Protein Atlas survival analyses further support its clinical relevance, as elevated CHPT1 expression correlates with poor patient outcomes in CRC. Mechanistically, CHPT1-driven PC enrichment may sustain pro-survival signaling, while reducing lysophospholipid-mediated stress pathways. To therapeutically target this vulnerability, we investigated edelfosine (Edel), an alkyl-lysophospholipid that disrupts lipid rafts and inhibits PC biosynthesis upstream of CHPT1. Notably, edelfosine-mediated disruption of the Kennedy pathway enhances chemosensitivity in the resistant CRC model. Collectively, our study identifies CHPT1 and PC metabolism as central determinants of CRC drug response and proposes edelfosine-based metabolic reprogramming as a promising strategy to overcome resistance.

(1) Background: Adult neurogenesis within the hippocampus modulates hippocampal memory and is often dysregulated in diseases that cause memory dysfunction, notably Alzheimer's disease. We have discovered a novel modulator of hippocampal neurogenesis-low-density lipoprotein receptor-related protein 1 (LRP1). (2) Methods: Using an inducible knockout of LRP1, male and female mice were subject to loss of LRP1, specifically in adult-born neural stem cells at 3 months of age. (3) Results: After 6 months with the knockout, animals without LRP1 in adult-born neural stem cells displayed behavioral phenotypes consistent with deficits in working memory and hippocampal-mediated spatial memory. We also found that over time, increasing numbers of adult-born LRP1-knockout neurons were present, although those neurons were morphologically less complex with fewer dendrites than controls. Our data suggest that the increase in the total number of adult-born neurons 6 months after knockout is due to a subtle increase in hippocampal proliferation over time. (4) Conclusions: Altogether, our data suggest that LRP1 is an important and previously unknown regulator of hippocampal neurogenesis.

Anderson-Fabry disease (FD) is an X-linked lysosomal storage disorder caused by pathogenic variants in the GLA gene, resulting in deficient α-galactosidase A activity and progressive accumulation of globotriaosylceramide (Gb3) and its derivative lyso-Gb3 within lysosomes. Beyond substrate storage, FD involves a complex interplay of molecular, metabolic, and inflammatory disturbances that collectively drive multisystemic damage. It seems that Gb3 accumulation impairs autophagic flux, promotes mitochondrial dysfunction, and triggers endoplasmic reticulum stress, leading to oxidative imbalance and bioenergetic failure. Concurrently, activation of innate immune pathways, particularly the TLR4/NF-κB axis, induces pro-inflammatory cytokine release and endothelial dysfunction, while complement activation and adaptive immune responses contribute to chronic inflammation and fibrosis. These mechanisms define a sustained state of "metaflammation," linking lysosomal dysfunction to systemic inflammation. Understanding this molecular cross-talk provides a rationale for identifying novel biomarkers and designing therapies that go beyond enzymatic correction, including chaperone therapy, substrate reduction, and gene-based or anti-inflammatory approaches. A deeper comprehension of these interconnected patterns may guide the development of precision medicine strategies aimed at improving long-term outcomes in Fabry disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its consequences represent a growing global health burden that urgently requires physiologically relevant in vitro models beyond conventional 2D culture systems. In this study, we report the successful establishment of 45 patient-derived liver organoid lines. These organoids were generated from healthy, steatotic and cirrhotic tissues collected from 207 liver surgeries at RWTH University Hospital Aachen, with an initiation success rate of 82%. The organoids were propagated for at least six passages using an optimized protocol. Multiplex immunofluorescence analysis revealed highly proliferative structures with approximately 40% Ki-67-positive cells expressing hepatocyte (Albumin and HNF4α) and cholangiocyte (CK19) markers. Intermittent LGR5 staining suggested the presence of liver progenitor cell features. Quantitative PCR results confirmed variable HNF4α expression, indicating inter-patient heterogeneity in differentiation status. Time-lapse imaging combined with mathematical modeling uncovered a biphasic growth dynamic with an initial linear expansion in the first 15 h, followed by exponential growth (doubling time ≈ 20.6 h) between 30 and 72 h. Overall, our workflow produced genetically and phenotypically stable liver organoids that recapitulate essential features of various hepatic conditions. This provides a solid foundation for disease modeling, potential drug testing, and quantitative systems biology.

Plexiform neurofibromas associated with neurofibromatosis type I (pNF1s) are benign tumors caused by the complete loss of function of the NF1 gene, which encodes a negative regulator of the RAS/mitogen-activated protein kinase (MAPK) pathway. pNF1s carry a significant risk of progression to malignant peripheral nerve sheath tumors (MPNSTs), which are highly aggressive and largely incurable. FDA-approved mitogen-activated protein kinase kinase (MEK) inhibitors, selumetinib and mirdametinib, have shown ~30% tumor shrinkage in 70% and 42% pNF1 patients, respectively. However, not all pNF1s respond to MEK inhibition, and treatment is often associated with adverse effects such as dermatologic and gastrointestinal toxicities, underscoring the need for improved therapeutic strategies with minimal side effects. Here, we demonstrate that prolonged MEK inhibition increases proteolytic activity in 3D pNF1 tumor structures, consistent with enhanced extracellular matrix degradation. Prolonged treatment with four mechanistically and chemically distinct MEK inhibitors consistently reduced ERK phosphorylation, a downstream effector of the RAS/MAPK pathway, yet induced adaptive phosphorylation of MEK and AKT in pNF1 tumor cells. Phosphorylation of MEK is required for its catalytic activation and subsequent phosphorylation of ERK. Increased MEK phosphorylation in the presence of MEK inhibitors reflects upstream pathway reactivation but does not lead to ERK phosphorylation and activation because of the presence of the inhibitor. This response was also observed in MPNST cell lines treated with MEK inhibitors. These findings suggest that adaptive activation of upstream and parallel survival pathways may counteract the intended effects of MEK inhibition and support the rationale for combination strategies to improve therapeutic outcomes in NF1-associated tumors.