Cdc42-Dependent Transfer of mir301 from Breast Cancer-Derived Extracellular Vesicles Regulates the Matrix Modulating Ability of Astrocytes at the Blood–Brain Barrier

Breast cancer brain metastasis is a major clinical challenge and is associated with a dismal prognosis. Understanding the mechanisms underlying the early stages of brain metastasis can provide opportunities to develop efficient diagnostics and therapeutics for this significant clinical challenge. We have previously reported that breast cancer-derived extracellular vesicles (EVs) breach the blood–brain barrier (BBB) via transcytosis and can promote brain metastasis. Here, we elucidate the functional consequences of EV transport across the BBB. We demonstrate that brain metastasis-promoting EVs can be internalized by astrocytes and modulate the behavior of these cells to promote extracellular matrix remodeling in vivo. We have identified protein and miRNA signatures in these EVs that can lead to the interaction of EVs with astrocytes and, as such, have the potential to serve as targets for development of diagnostics and therapeutics for early detection and therapeutic intervention in breast cancer brain metastasis

Cdc42-Dependent Transfer of mir301 from Breast Cancer-Derived Extracellular Vesicles Regulates the Matrix Modulating Ability of Astrocytes at the Blood–Brain Barrier

Breast cancer brain metastasis is a major clinical challenge and is associated with a dismal prognosis. Understanding the mechanisms underlying the early stages of brain metastasis can provide opportunities to develop efficient diagnostics and therapeutics for this significant clinical challenge. We have previously reported that breast cancer-derived extracellular vesicles (EVs) breach the blood–brain barrier (BBB) via transcytosis and can promote brain metastasis. Here, we elucidate the functional consequences of EV transport across the BBB. We demonstrate that brain metastasis-promoting EVs can be internalized by astrocytes and modulate the behavior of these cells to promote extracellular matrix remodeling in vivo. We have identified protein and miRNA signatures in these EVs that can lead to the interaction of EVs with astrocytes and, as such, have the potential to serve as targets for development of diagnostics and therapeutics for early detection and therapeutic intervention in breast cancer brain metastasis

Serum Protein Signatures Using Aptamer-Based Proteomics for Minimal Change Disease and Membranous Nephropathy

Introduction: Minimal change disease (MCD) and membranous nephropathy (MN) are glomerular diseases (glomerulonephritis [GN]) that present with the nephrotic syndrome. Although circulating PLA2R antibodies have been validated as a biomarker for MN, the diagnosis of MCD and PLA2R-negative MN still relies on the results of kidney biopsy or empirical corticosteroids in children. We aimed to identify serum protein biomarker signatures associated with MCD and MN pathogenesis using aptamer-based proteomics. Methods: Quantitative SOMAscan proteomics was applied to the serum of adult patients with MCD (n = 15) and MN(n = 37) and healthy controls (n = 20). Associations between the 1305proteins detected with SOMAscan were assessed using multiple statistical tests, expression pattern analysis, and systems biology analysis. Results: A total of 208 and 244 proteins were identified that differentiated MCD and MN, respectively, with high statistical significance from the healthy controls (Benjamin-Hochberg [BH] P \u3c 0.0001). There were 157 proteins that discriminated MN from MCD (BH P \u3c 0.05). In MCD, 65 proteins were differentially expressed as compared with MN and healthy controls. When compared with MCD and healthy controls, 44 discriminatory proteins were specifically linked to MN. Systems biology analysis of these signatures identified cell death and inflammation as key pathways differentiating MN from MCD and healthy controls. Dysregulation of fatty acid metabolism pathways was confirmed in both MN and MCD as compared with the healthy subjects. Conclusion: SOMAscan represents a promising proteomic platform for biomarker development in GN. Validation of a greater number of discovery biomarkers in larger patient cohorts is needed before these data can be translated for clinical care

Shear Stress Markedly Alters the Proteomic Response to Hypoxia in Human Pulmonary Endothelial Cells

Blood flow produces shear stress that homeostatically regulates the phenotype of pulmonary endothelial cells, exerting antiinflammatory and antithrombotic actions and maintaining normal barrier function. Hypoxia due to diseases, such as chronic obstructive pulmonary disease (COPD), causes vasoconstriction, increased vascular resistance, and pulmonary hypertension. Hypoxia-induced changes in endothelial function play a central role in the development of pulmonary hypertension. However, the interactive effects of hypoxia and shear stress on the pulmonary endothelial phenotype have not been studied. Human pulmonary microvascular endothelial cells were cultured in normoxia or hypoxia while subjected to physiological shear stress or in static conditions. Unbiased proteomics was used to identify hypoxia-induced changes in protein expression. Using publicly available single-cell RNA sequencing datasets, differences in gene expression between the alveolar endothelial cells from COPD and healthy lungs were identified. Sixty proteins were identified whose expression changed in response to hypoxia in conditions of physiological shear stress but not in static conditions. These included proteins that are crucial for endothelial homeostasis (e.g., JAM-A [junctional adhesion molecule A], ERG [ETS transcription factor ERG]) or implicated in pulmonary hypertension (e.g., thrombospondin-1). Fifty-five of these 60 have not been previously implicated in the development of hypoxic lung diseases. mRNA for 5 of the 60 (ERG, MCRIP1 [MAPK regulated corepressor interacting protein 1], EIF4A2 [eukaryotic translation initiation factor 4A2], HSP90AA1 [heat shock protein 90 alpha family class A member 1], and DNAJA1 [DnaJ Hsp40 (heat shock protein family) member A1]) showed similar changes in the alveolar endothelial cells of COPD compared with healthy lungs in females but not in males. These data show that the proteomic responses of the pulmonary microvascular endothelium to hypoxia are significantly altered by shear stress and suggest that these shear-hypoxia interactions are important in the development of hypoxic pulmonary vascular disease.Science Foundation IrelandEuropean Commission Horizon 2020Marie Skłodowska-Curie grant2024-02-02 JG check funders list add E

Aptamer Proteomics of Serum Exosomes From Patients With Primary Raynaud\u27s and Patients With Raynaud\u27s at Risk of Evolving into Systemic Sclerosis

BACKGROUND: A major unmet need for Systemic Sclerosis (SSc) clinical management is the lack of biomarkers for the early diagnosis of patients with Raynaud\u27s Phenomenon at high risk of evolving into SSc. OBJECTIVE: To identify proteins contained within serum exosomes employing an aptamer proteomic analysis that may serve to reveal patients with Raynaud\u27s Phenomenon at risk of developing SSc. METHODS: Exosomes were isolated from serum samples from patients with Primary Raynaud\u27s Phenomenon and from patients with Raynaud\u27s Phenomenon harbouring serum antinuclear antibodies (ANA) who may be at high risk of evolving into SSc. The expression of 1,305 proteins was quantified using SOMAscan aptamer proteomics, and associations of the differentially elevated or reduced proteins with the clinical subsets of Raynaud\u27s Phenomenon were assessed. RESULTS: Twenty one differentially elevated and one differentially reduced (absolute fold change \u3e|1.3|) proteins were identified. Principal component analysis using these 22 most differentially expressed proteins resulted in excellent separation of the two Raynaud\u27s Phenomenon clinical subsets. Remarkably, the most differentially elevated proteins are involved in enhanced inflammatory responses, immune cell activation and cell migration, and abnormal vascular functions. CONCLUSION: Aptamer proteomic analysis of circulating exosomes identified differentially elevated or reduced proteins between Raynaud\u27s Phenomenon at high risk of evolving into SSc and Primary Raynaud\u27s Phenomenon patients. Some of these proteins are involved in relevant biological pathways that may play a role in SSc pathogenesis including enhanced inflammatory responses, immune cell activation, and endothelial cell and vascular abnormalities

Scholarly communication in transition: The use of question marks in the titles of scientific articles in medicine, life sciences and physics 1966–2005

The titles of scientific articles have a special significance. We examined nearly 20 million scientific articles and recorded the development of articles with a question mark at the end of their titles over the last 40 years. Our study was confined to the disciplines of physics, life sciences and medicine, where we found a significant increase from 50% to more than 200% in the number of articles with question-mark titles. We looked at the principle functions and structure of the titles of scientific papers, and we assume that marketing aspects are one of the decisive factors behind the growing usage of question-mark titles in scientific articles

Delta isobar masses, large N_c relations, and the quark model

Motivated by recent remarks on the Delta+ mass and comparisons between the quark model and relations based on large-N_c with perturbative flavor breaking, two sets of Delta masses consistent with these constraints are constructed. These two sets, based either on an experimentally determined mass splitting or a quark model of isospin symmetry breaking, are shown to be inconsistent. The model dependence of this inconsistency is examined, and suggestions for improved experiments are made. An explicit quark model calculation and mass relations based on the large-N_c limit with perturbative flavor breaking are compared. The expected level of accuracy of such relations is realized in the quark model, except for mass relations spanning more than one SU(6) representation. It is shown that the Delta0 and Delta++ pole masses and Delta0 - Delta+ = (Delta- - Delta++)/3 about 1.5 MeV are more consistent with model expectations than the analogous Breit-Wigner masses and their splittings.Comment: 10 pages, including 1 eps figure, revte

Preliminary Biomarkers for Identification of Human Ascending Thoracic Aortic Aneurysm

Background: Human ascending thoracic aortic aneurysms (ATAAs) are life threatening and constitute a leading cause of mortality in the United States. Previously, we demonstrated that collagens α2(V) and α1(XI) mRNA and protein expression levels are significantly increased in ATAAs. Methods and Results: In this report, the authors extended these preliminary studies using high‐throughput proteomic analysis to identify additional biomarkers for use in whole blood real‐time RT‐PCR analysis to allow for the identification of ATAAs before dissection or rupture. Human ATAA samples were obtained from male and female patients aged 65±14 years. Both bicuspid and tricuspid aortic valve patients were included and compared with nonaneurysmal aortas (mean diameter 2.3 cm). Five biomarkers were identified as being suitable for detection and identification of ATAAs using qRT‐PCR analysis of whole blood. Analysis of 41 samples (19 small, 13 medium‐sized, and 9 large ATAAs) demonstrated the overexpression of 3 of these transcript biomarkers correctly identified 79.4% of patients with ATAA of ≥4.0 cm (P<0.001, sensitivity 0.79, CI=0.62 to 0.91; specificity 1.00, 95% CI=0.42 to 1.00). Conclusion: A preliminary transcript biomarker panel for the identification of ATAAs using whole blood qRT‐PCR analysis in men and women is presented

Higher C-reactive Protein Levels Predict Postoperative Delirium in Older Patients Undergoing Major Elective Surgery: A Longitudinal Nested Case-Control Study

Background—Delirium is a common, morbid, and costly postoperative complication.. We aimed to identify blood-based postoperative delirium markers in a nested case control study of older surgical patients using a proteomics approach followed by enzyme-linked immunosorbent assay (ELISA) validation. Methods and Materials—The Successful Aging after Elective Surgery Study enrolled dementia-free adults age ≥70 undergoing major scheduled non-cardiac surgery (N=566; 24% delirium). Plasma was collected at 4 timepoints: preoperatively (PREOP), post-anesthesia care unit (PACU), postoperative day 2 (POD2) and 1 month follow-up (PO1MO). Matched pairs were selected for the independent discovery (39 pairs) and replication cohorts (36 pairs), which were subsequently combined into the pooled cohort (75 pairs). iTRAQ-based relative quantitation mass spectrometry proteomics was performed to identify the strongest delirium-related protein, which was selected for ELISA validation. Using the ELISA results, statistical analyses using non-parametric signed-rank tests were performed in all cohorts examining the association between the identified protein and delirium. Results—C-reactive protein (CRP) emerged from the proteomics analysis as the strongest delirium-related protein. ELISA validation confirmed that compared to controls, cases had significantly higher CRP levels (*p\u3c.05, **p\u3c.01) in the discovery, replication, and pooled cohorts at PREOP (median paired difference [mg/L] 1.97*, 0.29, 1.56**, respectively), PACU (2.83, 2.22*, 2.53**, respectively) and POD2 (71.97**, 35.18*, 63.76**, respectively), but not PO1MO (2.72, −0.66, 1.10, respectively). Discussion—Elevated pre- and postoperative plasma levels of CRP were associated with delirium, suggesting that a pre-inflammatory state and heightened inflammatory response to surgery are potential pathophysiological mechanisms of delirium

Stability and reproducibility of proteomic profiles measured with an aptamer-based platform

The feasibility of SOMAscan, a multiplex, high sensitivity proteomics platform, for use in studies using archived plasma samples has not yet been assessed. We quantified 1,305 proteins from plasma samples donated by 16 Nurses’ Health Study (NHS) participants, 40 NHSII participants, and 12 local volunteers. We assessed assay reproducibility using coefficients of variation (CV) from duplicate samples and intra-class correlation coefficients (ICC) and Spearman correlation coefficients (r) of samples processed (i.e., centrifuged and aliquoted into separate components) immediately, 24, and 48 hours after collection, as well as those of samples collected from the same individuals 1 year apart. CVs were <20% for 99% of proteins overall and <10% for 92% of proteins in heparin samples compared to 66% for EDTA samples. We observed ICC or Spearman r (comparing immediate vs. 24-hour delayed processing) ≥0.75 for 61% of proteins, with some variation by anticoagulant (56% for heparin and 70% for EDTA) and protein class (ranging from 49% among kinases to 83% among hormones). Within-person stability over 1 year was good (ICC or Spearman r ≥ 0.4) for 91% of proteins. These results demonstrate the feasibility of SOMAscan for analyses of archived plasma samples