Molecular Biology and Genetics / Moleküler Biyoloji ve Genetik
Permanent URI for this collectionhttps://hdl.handle.net/11147/9
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Conference Object Investigation of the role of Wnt/β-catenin signaling in development of Alzheimer's disease in a zebrafish model of mmyloid-β toxicity(Wiley, 2024) Nazlı, Dilek; Ipekgil, D.; Poyraz, Y. K.; Catak, B.; Sahin, E. Turhanlar; Özhan, GüneşThe Wnt/β-catenin signaling pathway, an evolutionarily conserved and pivotal pathway associated with synapse formation in adulthood, plays a crucial role in Alzheimer's disease (AD). AD, marked by various pathologies, is primarily linked to the accumulation of extracellular beta-amyloid plaques. The interplay between this accumulation and disruptions in the Wnt/β-catenin signaling pathway triggers synaptic degeneration, resulting in synaptic dysfunction and AD progression. In this study, we modeled AD induced by the Aβ42 peptide using adult transgenic (6XTCF) zebrafish. To establish the zebrafish AD model, we employed cerebroventricular microinjection (CVMI) with the Aβ42 peptide. Fish, anesthetized prior to CVMI, were positioned on a stable platform, and the Aβ42 peptide was injected into the telencephalon region of the brain by a capillary needle. Brain samples were collected on 1, 3, 4, 7, and 14 days post-CVMI (dpi) to analyze changes in Aβ42 peptide accumulation, the immune system response, synaptic degeneration, apoptosis, and the expression of genes related to proliferation using qPCR and immunofluorescent staining. To examine the role of the Wnt/β-catenin signaling pathway in the molecular mechanism of AD development, fish exhibiting high levels of regeneration on days 7 and 14 were treated with the IWR-1 drug, which inhibits the Wnt/β-catenin signaling by stabilizing the Axin2 protein, thereby suppressing the regenerative response. Our results revealed that the AD model manifested on 3dpi, with the regenerative response reaching its peak on 7dpi and 14dpi. Treatment with IWR-1 resulted in increased Aβ42 accumulation, accelerated synaptic degeneration, and elevated cell deaths in fish where the Wnt signaling pathway was inhibited. In conclusion, our adult zebrafish AD model is poised to elucidate the molecular mechanisms connecting the Wnt signaling pathway and AD, thereby contributing to the development of alternative therapeutic approaches for AD patients.Article Citation - Scopus: 11Μdacs Platform: a Hybrid Microfluidic Platform Using Magnetic Levitation Technique and Integrating Magnetic, Gravitational, and Drag Forces for Density-Based Rare Cancer Cell Sorting(Elsevier, 2023) Keçili, Seren; Yılmaz, Esra; Özçelik, Özge Solmaz; Anıl İnevi, Müge; Günyüz, Zehra Elif; Yalçın Özuysal, Özden; Özçivici, Engin; Tekin, Hüseyin CumhurCirculating tumor cells (CTCs) are crucial indicators of cancer metastasis. However, their rarity in the bloodstream and the heterogeneity of their surface biomarkers present challenges for their isolation. Here, we developed a hybrid microfluidic platform (microfluidic-based density-associated cell sorting (µDACS) platform) that utilizes density as a biophysical marker to sort cancer cells from the population of white blood cells (WBCs). The platform utilizes the magnetic levitation technique on a microfluidic chip to sort cells based on their specific density ranges, operating under a continuous flow condition. By harnessing magnetic, gravitational, and drag forces, the platform efficiently separates cells. This approach involves a microfluidic chip equipped with a microseparator, which directs cells into top and bottom outlets depending on their levitation heights, which are inversely proportional to their densities. Hence, low-density cancer cells are collected from the top outlet, while high-density WBCs are collected from the bottom outlet. We optimized the sorting efficiency by varying the flow rates, and concentrations of the sorting medium's paramagnetic properties using standard densities of polymeric microspheres. To demonstrate the platform's applicability, we performed hybrid microfluidic sorting on MDA-MB-231 human breast cancer cells and U-937 human monocytes. The results showed efficient sorting of rare cancer cells (≥100 cells/mL) from serum samples, achieving a sorting efficiency of ∼70% at a fast-processing speed of 1 mL h−1. This label-free approach holds promise for rapid and cost-effective CTC sorting, facilitating in-vitro diagnosis and prognosis of cancer. © 2023 The Author(s)Article Citation - WoS: 5Citation - Scopus: 5De-Sealing Reverses Habitat Decay More Than Increasing Groundcover Vegetation(MDPI, 2023) Couch, Virginia; Salata, Stefano; Saygın, Nicel; Frary, Anne; Arslan, BertanModeling ecosystem services is a growing trend in scientific research, and Nature-based Solutions (NbSs) are increasingly used by land-use planners and environmental designers to achieve improved adaptation to climate change and mitigation of the negative effects of climate change. Predictions of ecological benefits of NbSs are needed early in design to support decision making. In this study, we used ecological analysis to predict the benefits of two NbSs applied to a university masterplan and adjusted our preliminary design strategy according to the first modeling results. Our Area of Interest was the IZTECH campus, which is located in a rural area of the eastern Mediterranean region (Izmir/Turkey). A primary design goal was to improve habitat quality by revitalizing soil. Customized analysis of the Baseline Condition and two NbSs scenarios was achieved by using local values obtained from a high-resolution photogrammetric scan of the catchment to produce flow accumulation and habitat quality indexes. Results indicate that anthropogenic features are the primary cause of habitat decay and that decreasing imperviousness reduces habitat decay significantly more than adding vegetation. This study creates a method of supporting sustainability goals by quickly testing alternative NbSs. The main innovation is demonstrating that early approximation of the ecological benefits of NbSs can inform preliminary design strategy. The proposed model may be calibrated to address specific environmental challenges of a given location and test other forms of NbSs.Review Citation - WoS: 14Citation - Scopus: 14Recent Advances in Lab-On Systems for Breast Cancer Metastasis Research(Royal Society of Chemistry, 2023) Fıratlıgil Yıldırır, Burcu; Yalçın Özuysal, Özden; NonappaBreast cancer is the leading cause of cancer-related deaths in women. Multiple molecular subtypes, heterogeneity, and their ability to metastasize from the primary site to distant organs make breast cancer challenging to diagnose, treat, and obtain the desired therapeutic outcome. As the clinical importance of metastasis is dramatically increasing, there is a need to develop sustainable in vitro preclinical platforms to investigate complex cellular processes. Traditional in vitro and in vivo models cannot mimic the highly complex and multistep process of metastasis. Rapid progress in micro- and nanofabrication has contributed to soft lithography or three-dimensional printing-based lab-on-a-chip (LOC) systems. LOC platforms, which mimic in vivo conditions, offer a more profound understanding of cellular events and allow novel preclinical models for personalized treatments. Their low cost, scalability, and efficiency have resulted in on-demand design platforms for cell, tissue, and organ-on-a-chip platforms. Such models can overcome the limitations of two- and three-dimensional cell culture models and the ethical challenges involved in animal models. This review provides an overview of breast cancer subtypes, various steps and factors involved in metastases, existing preclinical models, and representative examples of LOC systems used to study and understand breast cancer metastasis and diagnosis and as a platform to evaluate advanced nanomedicine for breast cancer metastasis.Article Citation - WoS: 4Citation - Scopus: 4Interferon Gamma-Inducible Nampt in Melanoma Cells Serves as a Mechanism of Resistance To Enhance Tumor Growth(MDPI, 2023) Barba, Cindy; Ekiz, Hüseyin Atakan; Tang, William Weihao; Ghazaryan, Arevik; Hansen, Mason; Lee, Soh-Hyun; Voth, Warren PeterSimple Summary The tumor microenvironment is complex, with interacting immune and tumor cells. Immune cells release inflammatory cytokines, including interferons (IFNs), that drive tumor clearance. However, evidence suggests that tumor cells can also utilize IFNs to enhance growth and survival in certain cases. We demonstrate that interferon gamma (IFN gamma) mediates the metabolic reprogramming of melanoma cells by inducing the essential NAD+ salvage pathway enzyme nicotinamide phosphoribosyltransferase (NAMPT) gene through STAT1 binding to the NAMPT locus. NAMPT is constitutively expressed in cells during normal homeostasis. However, melanoma cells have higher energetic demands and increased NAMPT. We show that IFN gamma signaling upregulates NAMPT in melanoma cells, increasing cell proliferation and survival. Further, STAT1-inducible Nampt promotes melanoma growth in mice. We provide evidence that melanoma cells directly respond to IFN gamma-activated STAT1 by increasing Nampt, which improves their fitness during tumor immunity. Elucidating mechanisms that regulate NAMPT expression can lead to enhanced therapeutic approaches with immunotherapies that utilize IFN signaling to improve patient outcomes. (1) Background: Immune cells infiltrate the tumor microenvironment and secrete inflammatory cytokines, including interferons (IFNs), to drive antitumor responses and promote tumor clearance. However, recent evidence suggests that sometimes, tumor cells can also harness IFNs to enhance growth and survival. The essential NAD+ salvage pathway enzyme nicotinamide phosphoribosyltransferase (NAMPT) gene is constitutively expressed in cells during normal homeostasis. However, melanoma cells have higher energetic demands and elevated NAMPT expression. We hypothesized that interferon gamma (IFN gamma) regulates NAMPT in tumor cells as a mechanism of resistance that impedes the normal anti-tumorigenic effects of IFN gamma. (2) Methods: Utilizing a variety of melanoma cells, mouse models, Crispr-Cas9, and molecular biology techniques, we explored the importance of IFN gamma-inducible NAMPT during melanoma growth. (3) Results: We demonstrated that IFN gamma mediates the metabolic reprogramming of melanoma cells by inducing Nampt through a Stat1 binding site in the Nampt gene, increasing cell proliferation and survival. Further, IFN/STAT1-inducible Nampt promotes melanoma in vivo. (4) Conclusions: We provided evidence that melanoma cells directly respond to IFN gamma by increasing NAMPT levels, improving their fitness and growth in vivo (control n = 36, SBS KO n = 46). This discovery unveils a possible therapeutic target that may improve the efficacy of immunotherapies involving IFN responses in the clinic.Conference Object Peptıde Targeted Core Cross-lınked Mıcelles For Dox Delıvery To Her2 Expressıng Cancer Cells(Mary Ann Liebert, 2022) Bayram, Nazende Nur; Ulu, Gizem Tuğçe; Gürdap, Seda; İşoğlu, İsmail Alper; Baran, Yusuf; Dinçer İşoğlu, SevilIn this study, we prepared a novel targeted and extra stable micellar nanocarrier that can facilitate intracellular drug release. First, ((N-3-sulfopropyl-N, N-dimethylammonium)ethyl methacrylate was synthesized by RAFT polymerization, and it was followed by copolymerization of macroCTA with AEM in the presence of an aciddegradable cross-linker. Then, a peptide estimated by phage display for HER-2 recognition was incorporated into these core cross-linked micelles with carbodiimide reaction.Article Citation - WoS: 6Citation - Scopus: 6A Comparative Study of Hplc and Uv Spectrophotometric Methods for Oseltamivir Quantification in Pharmaceutical Formulations(Akademiai Kiado, 2022) Güngör, Serdar; Bulduk, İbrahim; Aydın, Beyza Sultan; İlikçi Sağkan, RahşanOseltamivir is an antiviral drug and is used in the treatment of all influenza viruses. It is the most effective antiviral option against all influenza viruses that can infect humans. UV and LC methods have been developed and validated according to ICH guidelines for various parameters like selectivity, linearity, accuracy, precision, LOD and LOQ, robustness for the quantitative determination of oseltamivir in pharmaceutical formulations. LC method has been performed using reverse phase technique on a C-18 column with a mobile phase consisting of 20 mM potassium dihydrogen phosphate solution and acetonitrile (60:40, v/v) at 25 8C. The mobile phase flow rate was 1.2 mL min-1. For the determination of oseltamivir, UV spectrum has been recorded between 200 and 800 nm using methanol as solvent and the wavelength of 215 nm has been selected. Both methods have demonstrated good linearity, precision and recovery. No spectral and chromatographic interferences from the capsule excipients were found in UV and LC methods. In both methods, correlation coefficients were greater than 0.999 within a concentration range of 10???60 mg mL-1 using UV and LC. Intra-day and inter-day precision with low relative standard deviation values were observed. The accuracy of these methods was within the range 99.85???100.17% for LC and from 99.26 to 100.70% for UV. Therefore UV and LC methods gave the most reliable outcomes for the determination of oseltamivir in pharmaceutical formulation.Review Citation - WoS: 19Citation - Scopus: 22Cancer Stem Cells in Tumor Modeling: Challenges and Future Directions(John Wiley and Sons Inc, 2021) Dogan,E.; Kisim,A.; Bati-Ayaz,G.; Kubicek,G.J.; Pesen-Okvur,D.; Miri,A.K.Microfluidic tumors-on-chips models have revolutionized anticancer therapeutic research by creating an ideal microenvironment for cancer cells. The tumor microenvironment (TME) includes various cell types and cancer stem cells (CSCs), which are postulated to regulate the growth, invasion, and migratory behavior of tumor cells. In this review, the biological niches of the TME and cancer cell behavior focusing on the behavior of CSCs are summarized. Conventional cancer models such as 3D cultures and organoid models are reviewed. Opportunities for the incorporation of CSCs with tumors-on-chips are then discussed for creating tumor invasion models. Such models will represent a paradigm shift in the cancer community by allowing oncologists and clinicians to predict better which cancer patients will benefit from chemotherapy treatments. © 2021 The Authors. Advanced NanoBiomed Research published by Wiley-VCH GmbH.Article Citation - WoS: 4Citation - Scopus: 4Synthesis, Characterization, and Antimicrobial Activities of 3-Hpaa Nanoparticles(Techno Press, 2021) Özdemir, Özgün Öykü; Soyer, FerdaEncapsulation of bioactive compounds (e.g., phenolic acids) into nanoparticles is a well-received technique in the searching for new antimicrobial agents against multidrug-resistant pathogens. Encapsulation can be a good technique to maintain the stability of phenolic acids against environmental conditions. In this study, 3-hydroxyphenylacetic acid (3-HPAA) was encapsulated into alginate-chitosan nanoparticles with the ion gelation technique. The characterization of loaded and unloaded nanoparticles was performed via dynamic light scattering, Fourier transform infrared spectroscopy, and scanning electron microscopy. According to the results, 3-HPAA loaded nanoparticles have spherical shapes with a diameter range of 40-80 nm and an average hydrodynamic diameter of 361.0 +/- 69.8 nm. The loading of 3-HPAA was successfully achieved based on the Fourier transform infrared spectra and encapsulation percentage studies. The antimicrobial effect of the nanoparticles in solution forms was tested on P. aeruginosa, S. epidermidis, MRSA, and MSSA. The results demonstrated that the 3-HPAA loaded alginate chitosan nanoparticle solution showed elevated antimicrobial effect due to the pH change by treatment with 1% acetic acid, and it displayed bacteriocidal effects in a strain-specific and dose-dependent manner. Therefore, the 3-HPAA loaded alginate chitosan nanoparticle solution was produced successfully with the bacteriocidal effect against serious pathogenic bacteria.Article Citation - WoS: 5Citation - Scopus: 5Angelica Sylvestris and Delphinium Staphisagria Extracts Induces Antiproliferation Through Caspase-Mediated Apoptosis on Human Cancer Cells(Instituto de Tecnologia do Parana, 2022) Akgün, Oğuzhan; Akgün, Halime; Şahin, Çağatay; Çelikler, Serap; Arı, FerdaAngelica sylvestris and Delphinium staphisagria are medicinal and aromatic herbs with a long history in medicine and food industry. In this study, we have investigated anti-cancer activity of Angelica sylvestris and Delphinium staphisagria extracts on various cell lines of lung (A549), breast (MCF-7), colon (HT-29), and cervix (HeLa) origin. Also, cytotoxicity was tested on human healthy bronchial epithelial (BEAS-2B) cells. In vitro experiments showed that plant extracts suppressed cell growth and proliferation at low concentrations by reducing cell viability on cancer cells in a time and concentration-dependent manner. It was observed that Angelica sylvestris was more effective in HT-29 and HeLa cells and Delphinium staphisagria in A549 and MCF-7 cells by suppressing cell proliferation and increasing cell death. Cell death mode (apoptosis/necrosis) was investigated via fluorescent imaging, caspase-cleaved cytokeratin 18, activated caspase-3, and cleaved-PARP (poly (ADP-ribose) polymerase). In order to evaluate the cell death mode by plant extracts apoptotic markers were investigated by fluorescence staining. Delphinium staphisagria extract (50-200 μg/mL) caused a decrease in cell density in A549 and MCF-7 cells compared to untreated controls. A similar situation was observed in HT-29 and HeLa cell lines when treated with ASE. As a result, Delphinium staphisagria extracts induced apoptosis in A549 and MCF-7, while Angelica sylvestris extracts induced apoptosis in HT-29 and HeLa cancer cells