Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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  • Article
    Magnetic Levitation-Based Determination of Single-Nuclei Density
    (Elsevier, 2026) Anil-Inevi, Muge; Sarigil, Oyku; Unal, Yagmur Ceren; Tekin, H. Cumhur; Mese, Gulistan; Ozcivici, Engin
    The biophysical properties of cells and intracellular compartments provide critical insights into their structural and functional states, holding significant potential for biological and medical applications. Single-cell density has recently emerged as a promising biomarker in various research areas, including disease detection, making its precise measurement in biological samples an important analytical objective. Magnetic levitation offers significant advantages over traditional density detection techniques by enabling single-cell analysis rather than bulk measurements, providing precise quantification while preserving natural sample properties and eliminating the need for complex and expensive equipment. While magnetic levitation has been successfully applied to singlecell and cell-aggregate analysis, its use for subcellular compartments remains unexplored. Here, we demonstrate the first application of magnetic levitation technology for the density-based analysis of cell nuclei, a critical organelle essential for genomic preservation and organization. To accommodate the unique size and density characteristics of nuclei compared to whole cells, we systematically investigated appropriate paramagnetic agents, sample loading concentrations, and nuclear equilibrium times required for optimal levitation. We mapped density distributions of nuclei from different cell lines and conducted parallel assessments of cellular and nuclear density changes following cell cycle perturbations and treatments inducing cell death through distinct mechanisms. Our findings establish magnetic levitation as a powerful tool for subcellular density analysis, with potential applications in cell biology research and clinical diagnostics through improved understanding of subcellular physical parameters.
  • Article
    Storage Protein Allergen Sensitization Patterns in Children: Insights from Multiplex Microarray Profiling and Hierarchical Clustering
    (Wiley, 2025) Caka, Canan; Ozcivici, Engin; Karakus, Ceyda Oksel; Sekerel, Bulent Enis
    Background Storage proteins (SPs), including 2S albumins, vicilins, and legumins, are key allergenic molecules (AMs) of peanuts, tree nuts (TNs), and sesame. Their structural stability contributes to allergenicity and sensitization. This study explored SP AM clustering patterns and evaluated the test performance of multiplex microarray (MM) testing in a pediatric cohort. Methods We retrospectively analyzed 350 children (median age: 3.7 years) with detectable SP sensitizations (>= 0.1 kU(A)/L) using the ALEX(2) MM platform. Sensitization interrelationships were analyzed using correlation heatmaps, hierarchical clustering (HC), dimensionality reduction, and feature elimination. Predictive utility was assessed through ROC curve analysis at different sensitization cut-offs (>0.1 and >0.3 kU(A)/L) and total IgE thresholds (>0, >20, and >50 kU/L). Results HC identified a broad SP cluster spanning peanuts, TNs, sesame, poppy seed, and buckwheat. Strong correlations and early HC linkages suggested extensive cross-sensitization (e.g., Ana o 3-Pis v 1 and Jug r 4-Cor a 9), alongside evidence of co-sensitization and molecular spreading. Unexpected clustering of structurally dissimilar peanut and pistachio AMs pointed to shared epitopes and/or cross-contamination. 2S albumins (Ara h 2, Cor a 14, Jug r 1, Ana o 3, and Ses i 1) were most predictive for clinical reactivity. Lower cut-offs and exclusion of patients with low total IgE improved test performance. Alpha-hairpinin (Pap s 2S albumin) showed potential as specific markers. Conclusions MM testing enables detailed SP sensitization profiling. Cluster-based interpretation may clarify cross- vs. co-sensitization, supporting informed clinical decisions. Use of recombinant AMs and IgE stratification may further enhance MM utility in food allergy diagnostics.
  • Article
    Cx32 Cellular Localization Is Related To Epithelial To Mesenchymal Transition in Breast Cells
    (Pleiades Publishing inc, 2025) Oz, Sercan; Turan, Fatma Basak; Yondem, Eyup; Pesen-Okvur, Devrim; Yalcin-Ozuysal, Ozden; Ozcivici, Engin; Mese, Gulistan
    Connexins (Cx) play both gap junction-related and -independent roles in cells, and their localization is essential for their function in cellular processes. Besides membrane localization, connexins can also be localized to the cytoplasm and nucleus, especially in cancer cells. The differential localization of connexins including Cx32 was observed in different stages of cancers. Cx32 was upregulated and observed in cytoplasms of cells in lymph-node metastasis of breast cancer samples compared to primary tumors. However, the significance of the increase in Cx32 expression and alteration of Cx32 cellular localization in epithelial-to-mesenchymal transition (EMT) is not known. To determine if Cx32 overexpression and/or localization over one week would induce the EMT process, we first examined the cellular localization of Cx32 in MCF10A and MDA-MB-231 cells at different time points using Western blot and RT-PCR as well as immunostaining with confocal microscopy. Then, we correlated the changes of Cx32 expression and localization with EMT marker expression. We showed that Cx32 had altered cellular localization and Cx32 overexpression increased Slug levels while it reduced E-cadherin and Snail expression in MDA-MB-231 for 7 days. In contrast, E-cadherin and Vimentin were reduced in MCF10A-Cx32 cells compared with controls over 7 days, and the expression pattern for nuclear Cx32 and Zeb2 was following similar pattern in MCF10A cells. Our results suggest a previously unknown time-dependent relation between Cx32 and the regulation of the EMT process.
  • Article
    Comprehensive Analysis Of<i> Gjb1</I> in Breast Cancer: Its Implications in Survival and Molecular Mechanisms
    (int inst Anticancer Research, 2024) Ozcivici, Engin; Mese, Gulistan
    Background/Aim: Breast cancer is the leading cause of cancer-related mortality among women worldwide. The connexin (Cx) family, including GJB1 (Cx32), plays complex roles in tumor progression depending on cellular context and cancer subtype. While Cx32 overexpression has been linked to lymph node metastasis, its effects on survival and molecular processes remain unclear. Herein, we aimed to investigate the role of GJB1 in breast cancer by examining its impact on survival and cellular processes in addition to its expression pattern in tumor subtypes, using public datasets. Materials and Methods: We conducted a comprehensive analysis of GJB1 in breast cancer using METABRIC patient dataset, Cancer Cell Line Encylopedia, and other publicly available databases. We examined the association between GJB1 expression and patient survival, performed differential gene expression analysis, and explored gene set enrichment to identify biological processes associated with high GJB1 expression. Results: GJB1 was significantly down-regulated in breast cancer tissues compared to normal tissues. However, patients with high GJB1 expression had significantly poorer survival compared to those with low expression, with the median survival reduced by over 25 months. Gene ontology (GO) analysis revealed that down- regulated genes in the GJB1-high group were enriched in extracellular matrix components and membrane junctions, while up-regulated genes were associated with mitochondrial function and cellular respiration. Conclusion: Our findings suggest a dual role for GJB1 in breast cancer. Although it is generally down-regulated, high GJB1 expression is associated with poorer survival, implying a potential oncogenic role. Further studies are needed to clarify the role of GJB1 in breast cancer and explore its therapeutic implications.