Molecular Biology and Genetics / Moleküler Biyoloji ve Genetik
Permanent URI for this collectionhttps://hdl.handle.net/11147/9
Browse
5 results
Search Results
Conference Object Assessment of Cell Cycle and Viability of Magnetic Levitation Assembled Cellular Structures(IEEE, 2020) Anıl İnevi, Müge; Ünal, Yağmur Ceren; Yaman, Sena; Tekin, H. Cumhur; Meşe, Gülistan; Meşe, GülistanLabel-free magnetic levitation is one of the most recent Earth-based in vitro techniques that simulate the microgravity. This technique offers a great opportunity to biofabricate scaffold-free 3-dimensional (3D) structures and to study the effects of microgravity on these structures. In this study, self-assembled 3D living structures were fabricated in a paramagnetic medium by magnetic levitation technique and effects of the technique on cellular health was assessed. This magnetic force-assisted assembly system applied here offers broad applications in several fields, such as space biotechnology and bottom-up tissue engineering.Article Citation - Scopus: 1A Diaminoethane Motif Bearing Low Molecular Weight Polymer as a New Nucleic Acid Delivery Agent(Elsevier, 2021) Zelcak, Aykut; Ünal, Yağmur Ceren; Meşe, Gülistan; Bulmuş, VolgaAmong polymer-based gene delivery systems, poly(ethylene imine) (PEI) stands out as an effective polycation. However, the toxic effects of PEI especially at higher molecular weights limit its usage. Although the effects of PEI's architecture and molecular weight on gene delivery is controversial in literature, low molecular weight PEI appears to be efficient at transfection while having lower toxicity. Herein, as an alternative to low molecular weight, linear PEI, a methacrylate polymer bearing diamimoethane motifs, poly(2-((2-aminoethyl)amino)ethyl methacrylate) (P(AEAEMA)), was evaluated in vitro as a new nucleic acid delivery agent. P(AEAEMA) (8 kDa) showed low toxicity on Skov-3-luc and NIH/3T3 cell lines at polymer concentrations where PEI (8 kDa) was highly toxic. P(AEAEMA) could efficiently form complexes with siRNA at an N/P ratio of 2 as shown by gel electrophoresis. The diameter of P(AEAEMA)-siRNA complexes was found to be significantly lower than PEIsiRNA complexes almost at all tested N/P ratios. P(AEAEMA) could improve the stability of siRNA in serum containing media by protecting the siRNA against serum nucleases. siRNA and pDNA transfection efficiency of P (AEAEMA) on luciferase expressing Skov-3-luc cell line and HEK 293T cell line, respectively was found to be comparable to well-known nucleic acid carrier, PEI. The transfection efficiency of both P(AEAEMA) and PEI was found to be cell-type-dependent. None of the polymers were able to transfect MDA-MB-231 cells with siRNA or pDNA.Article Citation - WoS: 8Citation - Scopus: 8The Role of Connexins in Breast Cancer: From Misregulated Cell Communication To Aberrant Intracellular Signaling(Taylor & Francis, 2022) Ünal, Yağmur Ceren; Yavuz, Büşra; Özçivici, Engin; Meşe Özçivici, GülistanIn spite of clinical advancements and improved diagnostic techniques, breast cancers are the leading cause of cancer-associated deaths in women worldwide. Although 70% of early breast cancers can be cured, there are no efficient therapies against metastatic breast cancers. Several factors including connexins and gap junctions play roles in breast tumorigenesis. Connexins are critical for cellular processes as a linkage between connexin mutations and hereditary disorders demonstrated their importance for tissue homeostasis. Further, alterations in their expression, localization and channel activities were observed in many cancers including breast cancer. Both channel-dependent and independent functions of connexins were reported in initiation and progression of cancers. Unlike initial reports suggesting tumor suppressor functions, connexins and gap junctions have stage, context and isoform dependent effects in breast cancers similar to other cancers. In this review, we tried to describe the current understanding of connexins in tumorigenesis specifically in breast cancers.Article Citation - WoS: 22Citation - Scopus: 24Scaffold-Free Biofabrication of Adipocyte Structures With Magnetic Levitation(John Wiley and Sons Inc., 2021) Sarıgil, Öykü; Yalçın Özuysal, Özden; Anıl İnevi, Müge; Meşe Özçivici, Gülistan; Fıratlıgil Yıldırır, Burcu; Fıratlıgil Yıldırır, Burcu; Ünal, Yağmur Ceren; Ünal, Yağmur Ceren; Yalçın Özuysal, Özden; Özçivici, Engin; Meşe, Gülistan; Sarıgil, Öykü; Özçivici, Engin; Anıl İnevi, Müge; Meşe Özçivici, GülistanTissue engineering research aims to repair the form and/or function of impaired tissues. Tissue engineering studies mostly rely on scaffold-based techniques. However, these techniques have certain challenges, such as the selection of proper scaffold material, including mechanical properties, sterilization, and fabrication processes. As an alternative, we propose a novel scaffold-free adipose tissue biofabrication technique based on magnetic levitation. In this study, a label-free magnetic levitation technique was used to form three-dimensional (3D) scaffold-free adipocyte structures with various fabrication strategies in a microcapillary-based setup. Adipogenic-differentiated 7F2 cells and growth D1 ORL UVA stem cells were used as model cells. The morphological properties of the 3D structures of single and cocultured cells were analyzed. The developed procedure leads to the formation of different patterns of single and cocultured adipocytes without a scaffold. Our results indicated that adipocytes formed loose structures while growth cells were tightly packed during 3D culture in the magnetic levitation platform. This system has potential for ex vivo modeling of adipose tissue for drug testing and transplantation applications for cell therapy in soft tissue damage. Also, it will be possible to extend this technique to other cell and tissue types.Article Citation - WoS: 16Citation - Scopus: 18Connexin 32 Induces Pro-Tumorigenic Features in Mcf10a Normal Breast Cells and Mda-Mb Metastatic Breast Cancer Cells(Elsevier, 2020) Yalçın Özuysal, Özden; Adak, Aslı; Ünal, Yağmur Ceren; Yücel, Simge; Vural, Zehra; Turan, Fatma Başak; Meşe, GülistanConnexins (Cx), the basic subunit of gap junctions, play important roles in cell homeostasis, and their abnormal expression and function are associated with human hereditary diseases and cancers. In tumorigenesis, connexins were observed to have both anti-tumorigenic and pro-tumorigenic roles in a context- and stage-dependent manner. Initially, Cx26 and Cx43 were thought to be the only connexins involved in normal breast homeostasis and breast cancer. Later on, association of Cx32 expression with lymph node metastasis of breast cancer and subsequent demonstration of its expression in normal breast tissue suggested that Cx32 contributes to breast tissue homeostasis. Here, we aimed to determine the effects of Cx32 on normal breast cells, MCF10A, and on breast cancer cells, MDA-MB-231. Cx32 overexpression had profound effects on MCF10A cells, decreasing cell proliferation by increasing the doubling time of MCF10A. Furthermore, MCF10A cells acquired mesenchymal-like appearance upon Cx32 expression and had increased migration capacity and expression of both E-cadherin and vimentin. In contrast, Cx32 overexpression altered the EMT markers of MDA-MB-231 by increasing the expression of mesenchymal markers, such as slug and vimentin, and decreasing E-cadherin expression without affecting their proliferation and morphology. Our results indicate, for the first time in the literature, that Cx32 has tumor-promoting roles in MCF10A and MDA-MB-231 cells.