Search Results (133)

Brassinosteroids (BRs) are essential regulators of plant development and stress responses, but the distinct contributions of BR biosynthesis and signaling to hormonal crosstalk remain poorly defined. Here, we investigated the effects of the BR biosynthesis inhibitor brassinazole (BRZ) and the BR-insensitive mutant bri1-6 on endogenous phytohormone profiles in Arabidopsis thaliana. Using multivariate analysis and targeted hormone quantification, we show that BRZ treatment and BRI1 disruption alter hormone balance through partially overlapping but mechanistically distinct pathways. Principal component analysis (PCA) and hierarchical clustering revealed that BRZ and the bri1-6 mutation do not phenocopy each other and that BRZ still alters hormone profiles even in the bri1-6 mutant, suggesting potential BRI1-independent effects. Both BRZ treatment and the bri1-6 mutation tend to influence cytokinins and auxin conjugates divergently. On the contrary, their effects on stress-related hormones converge: BRZ decreases salicylic acid (SA), jasmonic acid (JA), and abscisic acid (ABA) in the WT leaves; similarly, bri1-6 mutants show reduced SA, JA, and ABA. These results indicate that BR biosynthesis and BRI1-mediated perception may contribute independently to hormonal reprogramming, with BRZ eliciting additional effects, possibly via metabolic feedback, compensatory signaling, or off-target action. Hormone correlation analyses revealed conserved co-regulation clusters that reflect underlying regulatory modules. Altogether, our findings provide evidence for a partial uncoupling of BR levels and BR signaling and illustrate how BR pathways intersect with broader hormone networks to coordinate growth and stress responses. Full article

Background: Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disorder characterized by left ventricular hypertrophy in the absence of secondary causes. This study aimed to investigate the genetic, clinical, and epidemiological profile of individuals with clinical HCM or a family history of sudden cardiac death (SCD). Methods: A total of 200 participants (58% male, median age 52 years) underwent genetic testing using a 19-gene panel associated with HCM and phenocopies. Variants were classified as pathogenic/likely pathogenic (P/LP), variants of uncertain significance (VUS), or negative. Clinical and imaging data were correlated with genetic findings. Results: P/LP variants were identified in 31% of individuals, while 40.5% carried VUS, and 28.5% tested negative. A positive genotype was more frequent among patients with clinical HCM (37.7%) than among those with only a family history (18.6%, p = 0.006). Sarcomeric mutations represented 77.4% of positive results, while 22.6% involved phenocopy genes, notably TTR (amyloidosis). Positive genotypes were significantly associated with a family history of SCD (68% vs. 46%, p = 0.004) and with greater interventricular septal thickness (17 mm vs. 15 mm, p < 0.001). Conclusions: Septal thickness >17 mm and family history of SCD were strong predictors of positive genetic results. These findings emphasize the importance of genetic screening and counseling in high-risk individuals and highlight the value of integrating genetic testing into clinical practice for diagnosis, risk stratification, and family management. Full article

The absent decline in cancer mortality rates is primarily due to moderate therapeutic efficacy and intrinsic or acquired tumor cell resistance toward treatments. Combining different oncology treatments increases therapy success and decreases the chance of refractory tumor cells. Therefore, combination cancer treatments are the principal paradigm of 21st-century oncology. Physical modalities such as radiotherapy have a long-standing tradition in such combination treatments. In the last decade, another physical principle emerged as a promising anticancer agent: cold gas plasma. This partially ionized gas, operated at about body temperature, emits multiple bioactive components, including reactive oxygen and nitrogen species (ROS/RNS). This technology’s multi-ROS/RNS nature cannot be phenocopied by other means, and it capitalizes on the vulnerability of tumor cells within metabolic and redox signaling pathways. Many cancer models exposed to mono or combination gas plasma treatments have shown favorable results, and first cancer patients have benefited from cold gas plasma therapy. The main findings and proposed mechanisms of action are summarized. Considering the specific application modes, this review identifies promising gas plasma combination therapies within guideline-directed treatment schemes for several tumor entities. In conclusion, gas plasmas may become a potential (neo)adjuvant therapy to existing treatment modalities to help improve the efficacy of oncological treatments. Full article

Purpose: To investigate genotype–phenotype correlations in PRPH2-retinopathies in a cohort of 36 patients from the Oxford Eye Hospital and report on novel pathogenic variants. Methods: Clinical data, including best corrected visual acuities (BCVA), fundus autofluorescence (FAF), and optical coherence tomography (OCT) imaging, were analysed. Genetic testing was performed using next-generation sequencing (NGS). Results: In this cohort, 26 different PRPH2 variants, including 8 novel variants, were identified. Variants were clustered in the D2 loop of the protein. A diverse range of phenotypes were observed: pseudo-Stargardt pattern dystrophy (PSPD) (47.2%), adult-onset vitelliform macular dystrophy (AVMD) (22.2%), pattern dystrophy (PD) (25.0%), atypical macular dystrophy (2.8%), and retinitis pigmentosa (RP) (2.8%). The mean age of symptom onset was 44.0 ± 14.4 years. Mean BCVA was 0.20 ± 0.54 logMAR OD and 0.14 ± 0.29 logMAR OS at baseline and 0.33 ± 0.40 logMAR OD and 0.32 ± 0.40 logMAR OS after a mean follow up duration of 6.0 ± 3.2 years (range 1–11 years). A thickened ellipsoid zone (EZ) was noted in 34/36 patients with a mean EZ thickness of 44.3 ± 11.3 µm OD and 42.7 ± 11.6 µm OS. No clear genotype–phenotype correlations were observed. Conclusions: The significant phenotypic range described in this study is consistent with the previously reported phenotypic variability in PRPH2 retinopathy and emphasises the complexity of establishing genotype–phenotype correlations in this disease. The thickness of the EZ on OCT may serve as a useful biomarker in distinguishing PRPH2 retinopathy from other phenocopies. These findings contribute to improved understanding of PRPH2 retinopathy and help inform diagnosis and genetic counselling. Full article

Cancer stem cells (CSCs), a subpopulation of tumor cells endowed with self-renewal capacity, drive cancer initiation and progression. While long non-coding RNAs (lncRNAs) are increasingly recognized as critical regulators of CSC stemness, their specific roles in gastric cancer stem cells (GCSCs) remain poorly understood. This study investigates the functional significance of lncRNA TSPEAR-AS2 in modulating GCSC properties and uncovers its underlying molecular mechanisms. Through integrated whole-transcriptome sequencing, bioinformatics analysis, and validation in 48 paired gastric cancer tissues and adjacent normal tissues, TSPEAR-AS2 was identified as a differentially expressed lncRNA upregulated in both GCSCs and tumor samples. Functional experiments revealed that TSPEAR-AS2 overexpression significantly enhanced GCSC sphere-forming ability, proliferation, cell cycle progression, epithelial–mesenchymal transition (EMT), and expression of stemness markers (CD54, CD44, OCT4, NANOG, and SOX2) while suppressing apoptosis. Conversely, TSPEAR-AS2 knockdown attenuated these malignant phenotypes. In vivo tumorigenicity assays in nude mice further confirmed that TSPEAR-AS2 promotes tumor growth, with overexpression accelerating and knockdown inhibiting tumor formation. Mechanistically, bioinformatics predictions and dual-luciferase reporter assays established TSPEAR-AS2 as a competing endogenous RNA (ceRNA) that sponges miR-15a-5p, thereby derepressing the miR-15a-5p target gene CCND1. Rescue experiments demonstrated that overexpression of miR-15a-5p phenocopied TSPEAR-AS2 knockdown, reducing GCSC stemness, while miR-15a-5p inhibition rescued the effects of TSPEAR-AS2 suppression. Collectively, these findings reveal a novel TSPEAR-AS2/miR-15a-5p/CCND1 regulatory axis that sustains GCSC stemness and tumorigenicity. These results highlight TSPEAR-AS2 as a potential therapeutic target for eradicating gastric cancer stem cells and improving clinical outcomes. Full article

The molecular basis for the distinct intestinal tropism of infectious bronchitis virus (IBV) strains remains poorly understood. This study identifies the S2 subunit of the spike glycoprotein as the critical determinant conferring duodenal tropism to the IBV CSL strain. Comparative pathogenesis in specific-pathogen-free (SPF) chicks revealed that the CSL strain achieved significantly higher viral titers in the duodenum compared to strains D90, PYG QX1, and XXX QX5. This duodenal replication was associated with severe epithelial inflammation, characterized by upregulation of pro-inflammatory cytokines (IL-6, IL-17A, IL-22, TNF-α, IFN-β, IFN-γ) and disruption of barrier integrity via downregulation of tight junction proteins (Occludin, Claudin-1, ZO-1). Crucially, reverse genetics using the non-enterotropic D90 backbone demonstrated that recombinant viruses carrying the CSL-S2 gene (rD90-ΔS/CSL and rD90-ΔS2/CSL), but not those carrying CSL-S1 (rD90-ΔS1/CSL), replicated efficiently and induced inflammation in the duodenum, phenocopying wild-type CSL. In contrast, renal tropism was independent of the S2 subunit. These findings establish the S2 subunit as both necessary and sufficient for IBV duodenal tropism, uncoupling it from renal pathogenicity. This identifies S2 as a prime molecular target for developing next-generation vaccines against intestinal IBV pathotypes. Full article

Myocardial hypertrophy (MH) represents a complex and heterogeneous condition in the pediatric and young adult population. While rare in children, MH encompasses a wide spectrum of physiological and pathological entities, ranging from transient hypertrophy in the infants of diabetic mothers to progressive genetic hypertrophic cardiomyopathies (HCM) with significant morbidity and mortality. Differential diagnosis is critical, as many phenocopies—including metabolic, mitochondrial, and syndromic diseases—can mimic HCM. Echocardiography remains the first-line imaging modality, with cardiac magnetic resonance (CMR) and molecular diagnostics increasingly used for detailed characterization. Risk stratification tools, such as the HCM Risk-Kids model, support clinical decision-making but must be integrated with individualized assessment. Advances in prenatal screening and genetic testing have significantly improved outcomes, though long-term management requires multidisciplinary care. Understanding age-specific presentations and the underlying etiologies is essential for accurate diagnosis and targeted treatment. This review provides a comprehensive overview of cardiac hypertrophy from fetal life through young adulthood, with a focus on etiologies, diagnostic approaches, imaging modalities, and therapeutic strategies, and aims to guide clinicians through the evolving landscape of MH, emphasizing early recognition, comprehensive evaluation, and personalized care. Full article

The envelope stress response in Escherichia coli is primarily governed by the sigma factor RpoE (σ^E), which activates protective genes upon membrane perturbation. Under non-stress conditions, σ^E is sequestered by its anti-sigma factor RseA. In this study, we identify an unexpected role for the nitric-oxide-sensing repressor NsrR in dampening σ^E activity and repressing σ^E-dependent small RNAs, including rybB, micA, and micL. Overexpression of nsrR represses transcription from σ^E-dependent promoters and phenocopies σ^E inactivation, resulting in filamentous morphology and growth defects. Conversely, ΔnsrR de-represses σ^E targets, with additive effects in rseA mutants—supporting an RseA-independent regulatory role. Time-course analysis shows NsrR represses σ^E activity, with kinetics comparable to those of RseA. While in vitro assays failed to detect robust NsrR binding to σ^E target promoters, NsrR directly interacts with σ^E in bacterial two-hybrid assays. Structural modeling using AlphaFold3 supports a plausible NsrR–RpoE interaction interface. These findings suggest that NsrR functions as a noncanonical anti-sigma-like modulator of σ^E, integrating redox and envelope stress signals to maintain membrane homeostasis. Full article

The hypertrophic cardiomyopathy (HCM) clinical phenotype includes sarcomeric HCM, which is the most common form of inherited cardiomyopathy with a population prevalence of 1:500, and phenocopies such as cardiac amyloidosis and Anderson–Fabry disease, which are considered rare diseases. Identification of cardiac and non-cardiac red flags in the context of multi-organ syndrome, multimodality imaging, including echocardiography, cardiac magnetic resonance, and genetic testing, has a central role in the diagnostic pathway. Identifying the specific disease underlying the hypertrophic phenotype is very important since many disease-modifying therapies are currently available, and phase 3 trials for new treatments have been completed or are ongoing. In particular, many chemotherapy agents (alkylating agents, proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies targeting clonal cells) allowing one to treat AL amyloidosis, transthyretin stabilizers (tafamidis and acoramidis), and gene silencers (patisiran and vutrisiran) are available in transthyretin cardiac amyloidosis, and enzyme replacement therapies (agalsidase-alpha, agalsidase-beta, and pegunigalsidase-alpha) or oral chaperone therapy (migalastat) can be used in Anderson–Fabry disease. In addition, the introduction of cardiac myosin inhibitors (mavacamten and aficamten) has deeply modified the treatment of hypertrophic obstructive cardiomyopathy. The aim of this review is to describe the new disease-modifying treatments available in HCM and phenocopies in light of current scientific evidence. Full article

The protozoan parasite Toxoplasma gondii transitions between acute (tachyzoite) and chronic (bradyzoite) stages, enabling lifelong persistence in hosts. Iron depletion triggers bradyzoite differentiation, with the phosphotyrosyl phosphatase activator (PTPA) identified as a key regulator. Here, we define PTPA’s role in T. gondii pathogenesis. PTPA forms a ternary complex with PP2A A/C subunits, validated by reciprocal pull-down assays. Depleting PTPA impaired tachyzoite proliferation, invasion, and gliding motility, while stress-induced bradyzoites exhibited defective cyst formation and vacuolar swelling. Metabolic dysregulation included amylopectin accumulation and lipid droplet proliferation. The PP2A inhibitor LB-100 phenocopied PTPA depletion, suppressing tachyzoite growth and bradyzoite differentiation. TgPTPA emerges as a linchpin coordinating PP2A activity, metabolic flux, and lifecycle transitions. Its dual roles in acute virulence and chronic persistence, combined with LB-100’s efficacy, position the PTPA–PP2A axis as a promising target for antitoxoplasmosis strategies. Full article

Background: X-ALD is a white matter (WM) disease caused by mutations in the ABCD1 gene encoding the transporter of very-long-chain fatty acids (VLCFAs) into peroxisomes. Strikingly, the same ABCD1 mutation causes either devastating brain inflammatory demyelination during childhood or, more often, progressive spinal cord axonopathy starting in middle-aged adults. The accumulation of undegraded VLCFA in glial cell membranes and myelin has long been thought to be the central mechanism of X-ALD. Methods: This review discusses studies in mouse and drosophila models that have modified our views of X-ALD pathogenesis. Results: In the Abcd1 knockout (KO) mouse that mimics the spinal cord disease, the late manifestations of axonopathy are rapidly reversed by ABCD1 gene transfer into spinal cord oligodendrocytes (OLs). In a peroxin-5 KO mouse model, the selective impairment of peroxisomal biogenesis in OLs achieves an almost perfect phenocopy of cerebral ALD. A drosophila knockout model revealed that VLCFA accumulation in glial myelinating cells causes the production of a toxic lipid able to poison axons and activate inflammatory cells. Other mouse models showed the critical role of OLs in providing energy substrates to axons. In addition, studies on microglial changing substates have improved our understanding of neuroinflammation. Conclusions: Animal models supporting a primary role of OLs and axonal pathology and a secondary role of microglia allow us to revisit of X-ALD mechanisms. Beyond ABCD1 mutations, pathogenesis depends on unidentified contributors, such as genetic background, cell-specific epigenomics, potential environmental triggers, and stochasticity of crosstalk between multiple cell types among billions of glial cells and neurons. Full article

Background: Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease, affecting approximately 1 in 1000 individuals. This genetically heterogeneous condition is primarily caused by monoallelic pathogenic or likely pathogenic variants in the PKD1 and PKD2 genes, accounting for 78% and 15% of typical cases, respectively. Recently, the application of NGS methods has led to the identification of additional genes associated with ADPKD, which have been incorporated into routine diagnostic testing for detecting phenocopies of the disease. Methods: In this study, targeted NGS (tNGS) analysis of the main cystogenes associated with classic and atypical ADPKD was performed in a cohort of 218 patients clinically diagnosed with cystic nephropathies. Results: Genetic testing identified variants in 175 out of 218 cases (80.3%). Among these, 133 probands (76%) harbored likely pathogenic or pathogenic variants in one or more genes of the panel, while 42 individuals (24%) had a variant of unknown significance (VUS). Specifically, one or more class 4/5 variants in PKD1, PKD2, or both were identified in 111 (83.5%) probands. Remarkably, a pathogenic variant in the IFT140 gene was identified in 14 index cases (8% of positive individuals, 6.4% of the global cohort): 10 distinct loss-of-function (LoF) variants were identified (including four frameshift variants, four nonsense variants, and two splice site defects); one individual carried a second IFT140 missense variant classified as VUS. Furthermore, five affected family members were found to carry a P/LP LoF variant in IFT140. Conclusions: Our data support that IFT140 heterozygous IFT140 LoF variants result in an atypical, mild form of ADPKD, consisting of bilateral kidney cysts and renal functional decline at older ages. Furthermore, we describe the second pediatric patient with a mild form of ADPKD due to an IFT140 variant and discuss hyperuricemia as a previously unappreciated feature of this condition. Full article

Lung cancer, particularly non-small-cell lung cancer (NSCLC), remains a leading cause of cancer-related mortality, with cisplatin-based chemotherapy being a standard treatment. However, the development of chemoresistance significantly limits its efficacy, necessitating alternative therapeutic approaches. Here, we demonstrate the anticancer effects of the extracts of Allium pseudojaponicum Makino (APE), a salt-tolerant plant, in cisplatin-resistant NSCLC. Metabolite profiling using UPLC-Q-TOF-MS^E identified 13 major compounds, predominantly alkaloids (71.65%) and flavonoids (8.81%), with key bioactive constituents such as lycorine (29.81%), tazettine (17.22%), and tricetin (8.19%). APE significantly inhibited cell viability in A549 and H460 cells, reducing viability to 38.6% (A549-Ctr), 37.2% (A549-CR), 28.4% (H460-Ctr), and 30.4% (H460-CR) at 40 µg/mL after 48 h. APE also suppressed colony formation by over 90% in both 2D and soft agar assays, while showing no cytotoxicity in normal human keratinocytes up to 80 µg/mL. Flow cytometry analysis revealed APE-induced G1 phase arrest, with the G1 population increasing from 50.4% to 56.6% (A549-Ctr) and 47.5% to 58.4% (A549-CR), accompanied by reduced S phase populations. This effect was associated with the downregulation of G1/S transition regulators, including cyclin D1, CDK4, cyclin E, and CDK2. Furthermore, proteomic analysis identified STAT3 signaling as a major target of APE; APE decreased phosphorylated STAT3 and c-Myc expression, and STAT3 knockdown phenocopied the effects of APE. These findings highlight the potential of APE as a natural product-based therapeutic strategy for overcoming cisplatin resistance in NSCLC. Full article

Background/Objectives: PARP inhibitors (PARPi) are pivotal to treating homologous recombination repair-deficient (HRD) cancers, particularly BRCA1/2-mutated ovarian and breast cancers. However, most ovarian and breast cancers harbor wild-type (WT) BRCA1/2, limiting PARPi eligibility. This study aims to identify an approved drug that could induce a BRCAness phenotype, thereby sensitizing WT BRCA cancers to PARPi. Methods: Ovarian and breast cancer cell lines with WT BRCA1/2 were treated with ivosidenib. HR repair efficiency was assessed via RAD51 foci formation and reporter assays. Synthetic lethality with PARPi was evaluated using viability and colony formation assays. Mechanistic studies included RNA-binding protein pulldown, co-immunoprecipitation, and functional analyses of DNA repair pathways. YTHDC2′s role in HR was investigated through siRNA knockdown and rescue experiments. Results: Ivosidenib significantly reduced HR repair efficiency and sensitized cells to PARPi, inducing synthetic lethality. Mechanistically, ivosidenib directly bound YTHDC2, an m6A reader critical for HR. This interaction disrupted YTHDC2′s ability to promote DNA double-strand break repair via HR, evidenced by impaired recruitment of repair proteins (e.g., BRCA1, RAD51) and accumulation of DNA damage (γH2AX foci). YTHDC2 knockdown phenocopied ivosidenib effects, while overexpression rescued HR defects. Conclusions: Ivosidenib induces BRCAness in WT BRCA ovarian and breast cancers by targeting YTHDC2, thereby suppressing HR repair and enhancing PARPi sensitivity. This uncovers a novel, metabolism-independent mechanism of ivosidenib, repositioning it as a therapeutic agent for HRD tumors. These findings propose a strategy to expand PARPi eligibility to WT BRCA cancers, addressing a critical unmet need in oncology. Full article

The ability of an organism to regrow tissues is regulated by various signaling pathways. One such pathway that has been studied widely both in the context of regeneration and development is the Notch signaling pathway. Notch is required for the development of the eye and regeneration of tissues in multiple organisms, but it is unknown if Notch plays a role in the regulation of Xenopus laevis embryonic eye regrowth. We found that Notch1 is required for eye regrowth and regulates retinal progenitor cell proliferation. Chemical and molecular inhibition of Notch1 significantly decreased eye regrowth by reducing retinal progenitor cell proliferation without affecting retinal differentiation. Temporal inhibition studies showed that Notch function is required during the first day of regrowth. Interestingly, Notch1 loss-of-function phenocopied the effects of the inhibition of the proton pump, vacuolar-type ATPase (V-ATPase), where retinal proliferation but not differentiation was blocked during eye regrowth. Overexpression of a form of activated Notch1, the Notch intracellular domain (NICD) rescued the loss of eye regrowth due to V-ATPase inhibition. These findings highlight the importance of the Notch signaling pathway in eye regeneration and its role in inducing retinal progenitor cell proliferation in response to injury. Full article