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Impact of Active Surveillance on Nephrometric Scores of Bosniak III and IV Renal Cysts
No full textPurpose: Active surveillance (AS) has been widely explored for small renal masses, but its role in complex renal cysts (CRCs) categorized as Bosniak (Bk) III and IV remains unclear. This study aims to evaluate changes in nephrometry scores (s-RENAL and s-PADUA) during AS and their potential impact on surgical complexity.
Methods: A retrospective, multicentric, observational study was conducted, analyzing 101 CRCs from 95 patients across three institutions. Nephrometry scores were evaluated at baseline and after a minimum follow-up of two years using computed tomography (CT) and magnetic resonance imaging (MRI). Statistical analysis included chi-square and marginal homogeneity tests, with data managed using REDCap.
Results: Among the 101 CRCs, 39 were Bk IV and 62 Bk III, with a mean follow-up of 4.2 years. The initial mean lesion size was 2.77 cm (0.50-11.8 cm), increasing to 3.0 cm (0.40-13.10 cm) at follow-up. Complexity scores increased in 4% of cases according to s-RENAL and 5% according to s-PADUA. Tumor growth was observed in 45 cases (44.5%), while 37 (36.6%) remained stable, and 19 (18.8%) decreased in size. Bk IV cysts tended to increase in size more than Bk III and had a smaller chance of decreasing. Median growth and shrinkage velocities were 0.19 cm/year and 0.21 cm/year, respectively.
Conclusion: Active surveillance is a viable and safe strategy for managing select Bk III and IV CRCs. A small but significant proportion of CRCs under AS exhibit increased nephrometry complexity, which may impact surgical planning. These findings suggest that nephrometry score evolution should be considered when selecting patients for AS versus early surgical intervention
Lipidomic and Proteomic Insights From Extracellular Vesicles in the Postmortem Dorsolateral Prefrontal Cortex Reveal Substance Use Disorder-Induced Brain Changes
No full textSubstance use disorder (SUD) significantly increases the risk of neurotoxicity, inflammation, oxidative stress, and impaired neuroplasticity. The activation of inflammatory pathways by substances may lead to reactive astrogliosis and chronic neuroinflammation, potentially mediated by the release of extracellular particles (EPs), such as extracellular condensates (ECs) and extracellular vesicles (EVs). These particles, which reflect the physiological, pathophysiological, and metabolic states of their cells of origin, might carry molecular signatures indicative of SUD. In particular, our study investigated neuroinflammatory signatures in SUD patients by isolating EVs from the dorsolateral prefrontal cortex (dlPFC) Brodmann\u27s area 9 (BA9) from postmortem subjects. We isolated BA9-derived EVs from postmortem brain tissues of eight individuals (controls: n = 4, SUD: n = 4). The physical properties (concentration, size, zeta potential, morphology) of the EVs were analyzed, and the EVs were subjected to integrative multiomics analysis to profile the lipidomic and proteomic characteristics. We assessed the interactions and bioactivity of EVs by evaluating their uptake by glial cells. We further assessed the effects of EVs on complement mRNA expression in glial cells and on microglial migration. No significant differences in EV concentration, size, zeta potential, or surface markers were observed between the SUD group and the control group. However, lipidomic analysis revealed significant enrichment of glycerophosphoinositol bisphosphate (PIP2) in SUD-derived EVs. Proteomic analysis revealed the downregulation of SERPINB12, ACYP2, CAMK1D, DSC1, and FLNB and the upregulation of C4A, C3, and ALB in SUD-derived EVs. Gene Ontology (GO) and protein‒protein interactome analyses revealed functions associated with the identified proteins, such as cell motility, focal adhesion, and acute phase response signaling. Both control and SUD-derived EVs increased C3 and C4 mRNA expression in microglia, but only SUD-derived EVs upregulated these genes in astrocytes. SUD-EVs also significantly enhanced microglial migration in a wound healing assay. This study successfully isolated EVs from postmortem brains and used a multiomics approach to identify EV-associated lipids and proteins in SUD. Elevated C3 and C4 in SUD-derived EVs and the distinct effects of EVs on glial cells suggest a crucial role for these cells in acute phase response signaling and neuroinflammation
Identifying Bio-Behavioural Signatures of Persistent Opioid Use Risk in Trauma Injury Patients: A Protocol for a Prospective Cohort Study
No full textIntroduction: Exposure to prescription opioids following traumatic injury can increase the risk of developing tolerance, persistent opioid use and opioid use disorder. The mechanisms underlying opioid tolerance or dependence are not well understood, and no biomarkers predict risk. Opioid exposure causes epigenetic modifications, including alterations in microRNA (miRNA) expression. Several miRNAs, which regulate synaptic plasticity, are hypothesised to underlie substance use disorders and influence µ-opioid receptor levels, modulating opioid tolerance. This project aims to develop a bio-behavioural signature to predict persistent opioid use and chronic pain up to 6 months post-discharge.
Methods and analysis: The study will use a prospective cohort design, enrolling 180 adult patients at a Level I Trauma Center who are prescribed opioids at discharge. Prospective data will be collected in the hospital and at 7 days and 1, 3 and 6 months post-discharge. Biological data (genotyping and miRNA levels) and clinical measures of opioid use, pain, pain sensitivity (EEG) and psychosocial functioning will be collected at each time point. Bayesian regression methods will be used to identify baseline clinical, genetic, epigenetic and psychosocial predictors of opioid use and pain outcomes at 6 months post-discharge. Growth mixture modelling will identify distinct subgroups with varying trajectories, followed by Bayesian hierarchical modelling to predict trajectory classification based on predictor variables.
Ethics and dissemination plan: Ethics approval for this study was obtained from the University of Texas Health Science Center at Houston Committee for the Protection of Human Subjects (HSC-MS-24-0314). Findings will be disseminated in peer-reviewed scientific journals and at national and international conferences
Technical and Clinical Validity of Assessing Measurable Residual Disease by Multicolor Flow Cytometry in an Unselected Acute Myeloid Leukemia Patient Cohort
No full textContext.—: Following the validation of a multicolor flow cytometry (MFC) assay for measurable residual disease (MRD) in acute myeloid leukemia (AML), this study examines its clinical applicability.
Objective.—: To evaluate the practicality and performance of MFC-based MRD detection in AML.
Design.—: Prospectively assessed AML MRD MFC in unselected AML patients achieving morphologic remission with follow-up studies, molecular genetics, and survival data.
Results.—: Among 379 patient bone marrow samples in this cohort, an interpretable result was obtained in 359 (95%). A total of 57 of the 359 cases (16%) were positive for MRD, and the most frequently observed immunophenotype was CD34+CD117+ myeloid (n = 46; 81%), followed by CD34-/CD117+ myeloid (n = 8; 14%) and monocytic (n = 3; 5%). Of 57 MRD+ cases, 6 (11%) had no leukemia-associated immunophenotypes available, and 16 of 51 (31%) with leukemia-associated immunophenotype for comparison exhibited significant immunophenotypic drift/switch, highlighting the importance of the deviation from normal approach. The remaining 302 cases were MRD negative; among these, 21 (6%) displayed a preleukemic immunophenotype that was associated with persistent clonal hematopoiesis in 18 patients (86%). A positive MFC result was strongly associated with subsequent follow-up positive MRD (41 of 45 [91%] versus 14 of 240 [6%], P \u3c .01), morphologic relapse (42 of 55 [76%] versus 48 of 301 [16%], P \u3c .01), an inferior overall survival (12.5 months versus not reached, P \u3c .01), and leukemia-free survival (6.5 months versus not reached, P \u3c .01). Among MRD-negative patients, a preleukemic phenotype was associated with a shorter overall survival (P = .03), but not leukemia-free survival (P = .16).
Conclusions.—: Our study provides data-driven technical insights for laboratories considering MFC AML MRD implementation and offers strong evidence supporting the utility of MRD assessment by MFC in patients with AML undergoing various stages of treatment and surveillance
Poziotinib for EGFR Exon 20-Insertion NSCLC: Clinical Efficacy of the Phase 2 ZENITH Trial and Differential Impact of EGFR Exon 20 Insertion Location on Sensitivity
No full textEGFRex20 insertions (EGFRex20ins) can be classified as near- and far-loop based on the insertion location, however, the impact of location on responses to various EGFR tyrosine kinase inhibitors (TKIs) is poorly understood. In vitro studies show that afatinib, poziotinib, and zipalertinib more potently inhibited near-loop than far-loop insertions, whereas mobocertinib has similar IC50 in both groups. Molecular dynamics simulations reveal that near-loop insertions have multiple conformational states and lower transitional energy than far-loop insertions. ZENITH20 trial cohort 1 (NCT03318939) evaluates poziotinib in EGFRex20 NSCLC patients (n = 115) and demonstrates an objective response rate of 14.8% (95% Confidence Interval [CI], 8.9 to 22.6, primary endpoint of the trial). Although the study\u27s primary efficacy endpoint was not met in the overall cohort, the exploratory analysis indicates poziotinib has superior benefit in EGFRex20 near- versus far-insertions showing greater mean tumor size reduction (-25.9% vs. -9.8%, p = 0.0014) and progression-free survival (PFS, 11.1 vs. 3.5 months, p = 0.016). In comparison, in the previously published EXCLAIM trial (NCT02716116), mobocertinib demonstrates similar activities across both groups in tumor size reduction (-38.5% vs. -34.1%, p = 0.59) and PFS (12.0 vs. 13.0 months, p = 0.99). Therefore, EGFRex20ins location differentially impacts the sensitivity of TKIs
The Genomes of Nematode-Trapping Fungi Provide Insights Into the Origin and Diversification of Fungal Carnivorism
No full textNematode-trapping fungi (NTF), most of which belong to a monophyletic lineage in Ascomycota, cannibalize nematodes and other microscopic animals, raising questions regarding the types and mechanisms of genomic changes that enabled carnivorism and adaptation to the carbon-rich and nitrogen-poor environment created by the Permian-Triassic extinction event. To address these questions, we conducted comparative genomic analyses of 21 NTF and 21 non-NTF. Carnivorism-associated changes include expanded genes for nematode capture, infection, and consumption (e.g., adhesive proteins, CAP superfamily, eukaryotic aspartyl proteases, and serine-type peptidases). Although the link between secondary metabolite (SM) production and carnivorism remains unclear, we found that the number of SM gene clusters in NTF was significantly lower than that in non-NTF. Significantly expanded cellulose degradation gene families (GH5, GH7, AA9, and CBM1) and contracted genes for carbon-nitrogen hydrolases (enzymes that degrade organic nitrogen to ammonia) are likely associated with adaptation to carbon-rich and nitrogen-poor environments. Through horizontal gene transfer events from bacteria, NTF acquired the Mur gene cluster (participating in synthesizing peptidoglycan of the bacterial cell wall) and Hyl (a virulence factor in animals). Disruption of MurE reduced NTF\u27s ability to attract nematodes, supporting its role in carnivorism. This study provides new insights into how NTF evolved and diversified, presumably after the Permian-Triassic mass extinction event
A Switch Protein Adapter for Anti-LILRB4 CAR-T Cells
No full textChimeric antigen receptor-T cell (CAR-T) immunotherapy has shown remarkable results for the treatment of certain hematologic malignancies. A redirection strategy that utilizes clinically relevant CAR-T cells in combination with adapter proteins may be an effective strategy to target other hematologic and solid cancers. We established a fusion antibody-based strategy with flexibility to target multiple tumor types in combination with a novel anti-leukocyte immunoglobulin-like receptor-B 4 (LILRB4) CAR-T cell. Specifically, we engineered switch protein (SwP) adapters containing the LILRB4 extracellular domain fused to either an anti-CD19 or anti-CD20 single-chain variable fragment (scFv). These SwPs were sufficient to stimulate anti-LILRB4 CAR-T cells against SwP-tagged LILRB4−CD19+ and LILRB4−CD20+ cancers in vitro and in vivo. This strategy may allow CAR-T cells to be redirected against a variety of tumor antigens and cancer types and become a valuable approach to expand the impact of cellular immunotherapy
Somatostatin Receptor 2 Overexpression in Hepatocellular Carcinoma: Implications for Cancer Biology and Therapeutic Applications
No full textBackground: Somatostatin receptor 2 (SSTR2), a G protein-coupled receptor, is overexpressed in multiple malignancies, including hepatocellular carcinoma (HCC). While SSTR2 has traditionally been viewed as an inhibitory receptor involved in suppressing hormone secretion and cell proliferation, emerging evidence suggests a more complex role in cancer biology. However, the functional implications of SSTR2 expression in HCC remain poorly understood. This study aimed to systematically investigate the molecular landscape associated with SSTR2 expression in HCC and evaluate its potential as a therapeutic target.
Methods: SSTR2 expression patterns across 22 tumor types were assessed using TNMplot, and its expression in HCC was further validated through The Human Protein Atlas. Integrative analysis of transcriptomic profiles, protein expression data, and somatic copy number alterations was performed using data from The Cancer Genome Atlas (TCGA) to stratify HCC patients by SSTR2 expression levels. Gene Ontology (GO) enrichment analysis was conducted via SRplot to uncover biological processes and signaling pathways associated with SSTR2. Kaplan-Meier survival analyses were performed using GEO datasets to determine the prognostic significance of SSTR2 expression.
Results: SSTR2 is moderately expressed in the majority of HCC tumors. Elevated SSTR2 expression correlates with significantly poorer overall and disease-specific survival. High SSTR2 levels are associated with activation of oncogenic signaling cascades related to cell proliferation, epithelial-to-mesenchymal transition (EMT), angiogenesis, and metastasis. Additionally, SSTR2 expression is positively correlated with several receptor tyrosine kinases and oncogenes implicated in HCC progression.
Conclusions: Our findings suggest that SSTR2 is not merely a passive biomarker but may contribute to HCC pathogenesis through modulation of oncogenic pathways. These data support the rationale for further development of SSTR2-directed therapeutic strategies to inhibit tumor growth and invasion in HCC patients
Multifaceted Roles of Epac Signaling in Renal Functions
No full text3\u27,5\u27-cyclic adenosine monophosphate (cAMP) is a fundamental secondary messenger capable of rapidly amplifying and propagating cellular signals in response to various extracellular stimuli. cAMP plays a significant role in hormone-mediated regulation of renal fluid and electrolyte balance. Impaired signaling of cAMP has been linked to a variety of pathological ramifications in the kidneys. This review explores the physiological functions of exchange proteins directly activated by cAMP (Epac) in renal water balance and the regulation of solute transport in the renal tubule. Additionally, the involvement of Epac signaling in renal pathologies such as acute kidney injury, chronic kidney disease, and polycystic kidney disease is discussed
Structural Basis for mTORC1 Activation on the Lysosomal Membrane
No full textThe mechanistic target of rapamycin complex 1 (mTORC1) integrates growth factor (GF) and nutrient signals to stimulate anabolic processes connected to cell growth and inhibit catabolic processes such as autophagy1,2. GF signalling through the tuberous sclerosis complex regulates the lysosomally localized small GTPase RAS homologue enriched in brain (RHEB)3. Direct binding of RHEB-GTP to the mTOR kinase subunit of mTORC1 allosterically activates the kinase by inducing a large-scale conformational change4. Here we reconstituted mTORC1 activation on membranes by RHEB, RAGs and Ragulator. Cryo-electron microscopy showed that RAPTOR and mTOR interact directly with the membrane. Full engagement of the membrane anchors is required for optimal alignment of the catalytic residues in the mTOR kinase active site. Converging signals from GFs and nutrients drive mTORC1 recruitment to and activation on lysosomal membrane in a four-step process, consisting of (1) RAG-Ragulator-driven recruitment to within ~100 Å of the lysosomal membrane; (2) RHEB-driven recruitment to within ~40 Å; (3) RAPTOR-membrane engagement and intermediate enzyme activation; and (4) mTOR-membrane engagement and full enzyme activation. RHEB and membrane engagement combined leads to full catalytic activation and structurally explains GF and nutrient signal integration at the lysosome