PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
Browse
74 results
Search Results
Article Citation - WoS: 139Granulocytic Sarcoma: a Systematic Review(e-Century Publishing Corporation, 2013) Yılmaz, Asu Fergün; Saydam, Güray; Şahin, Fahri; Baran, YusufGranulocytic sarcoma also called myeloid sarcoma is an extramedullary tumor of immature granulocytic cells. It is a rare entity, and mostly accompanied by acute myeloid leukemia. It is observed during the course of myeloproliferative disorders especially in chronic myeloid leukemia and myelodysplastic syndromes. In some rare circumstances, it is detected before clinical signs of leukemia or other diseases. When the bone marrow biopsy reveals no other hematologic malignancies, the granulocytic sarcoma is described as nonleukemic, primary or isolated. It is observed at any part of the body but the most common locations are soft tissues, bone, peritoneum and lymph nodes. Presenting signs or symptoms are mainly due to mass effect of the tumor and dysfunction of the organ, or the tissue that is affected. The diagnosis is performed by biopsy of the tumor. The tumor consists of immature granulocytic cells, which could be documented by H&E, immunohistochemistry, and flow cytometric methods. Fluorescence in-situ hybridization and molecular analysis are also performed. The optimal time and type of treatment is not clear. Surgery could be an option especially for tumors, which cause organ dysfunction and/or obstruction. Systemic treatment should be considered in all patients because without systemic treatment, relapses and progression to acute myeloid leukemia is the ultimate fate of the disease in many cases. Cytarabine-containing remission-induction chemotherapies have been the most applied therapeutic strategies, but it is not clear whether the consolidation therapies are required or not, and what kind of regimens are appropriate. The role of hematopoietic stem cell transplantation (HSC) as a consolidation regimen is not clear, but, after the relapse of the disease with or without bone marrow involvement, HSC transplantation should be considered in suitable patients after the reinduction performed by AML chemotherapies. There is only limited data about the role of radiotherapy in these patients. It could be used in patients with relapsed disease, organ dysfunction which should be quickly relieved and inadequate response to chemotherapy. The effect of radiotherapy on overall survival is not known. New prospective studies and clinical trials are needed to generate guidelines for the treatment of primary granulocytic sarcomas.Article Citation - WoS: 37Mechanisms of Cellular Resistance To Imatinib in Human Chronic Myeloid Leukemia Cells(Taylor and Francis Ltd., 2007) Baran, Yusuf; Ural, Ali Uğur; Gündüz, UfukA major advancement in the treatment of chronic myeloid leukemia (CML) has been the development of imatinib, which has shown striking activity in the chronic phase and the accelerated phase, but less so in the blast phase of the disease. Despite high rates of hematologic and cytogenetic responses to therapy, the emergence of resistance to imatinib has been recognized as a major problem in the treatment of patients with CML. Various cellular mechanisms may be involved in the nature of cellular resistance. Increased amount of target, alteration in structure of target proteins, decreased drug uptake and increased detoxification are well-known mechanisms of resistance. On the other hand, in some cases, even if anticancer drugs reach their sites of action, bypassing drug efflux system of the cells, some cells still may survive via the dysregulation of apoptotic signalling. In this study, mechanisms of resistance to imatinib-induced apoptosis in human Meg-01 CML cells were examined. Continuous exposure of cells to step-wise increasing concentrations of imatinib resulted in the selection of 200- and 1000 nM imatinib-resistant sub-lines referred to as Meg-01/IMA-0,2 and Meg-01/1MA-1, respectively. MTT cell proliferation, cell cycle analyses and trypan blue dye exclusion analyses showed that Meg-0l/IMA-1 cells were resistant to imatinib-induced apoptosis as compared to parental sensitive cells. There was an increased expression of BCR/ABL, Bcl-2 and an increase in mitochondrial membrane potential (MMP) detected in resistant cells comparing to parental sensitive cells. There was no mutation detected in imatinib binding site of ABL kinase region. Various diverse mechanisms have been reported for their involvement in the multidrug resistance. In this study, it has been shown that the degree of BCR/ABL expression appears to be directly proportional to the levels of imatinib resistance. In addition, there have been BCR/ABL-independent mechanisms reported for deriving resistance against imatinib. Our results revealed that besides BCR/ABL overexpression, imatinib resistance also depends on the inhibition of apoptosis as a result of up-regulation of anti-apoptotic stimuli and down-regulation of pro-apoptotic stimuli through MMP but does not depend on any mutation on imatinib binding site of ABL kinase.Article Citation - WoS: 44Hesperidin Promotes Programmed Cell Death by Downregulation of Nongenomic Estrogen Receptor Signalling Pathway in Endometrial Cancer Cells(Elsevier Ltd., 2018) Cincin, Zeynep Birsu; Kıran, Bayram; Baran, Yusuf; Çakmakoğlu, BediaEndometrial carcinoma (EC) is the most common malignant gynecologic tumor in women. EC is thought to be caused by increasing estrogen levels relative to progesterone in the body. Hesperidin (Hsd), a biologically active flavonoid, could be extracted from Citrus species. It has been recently shown that Hsd could exert anticarcinogenic properties in different cancer types. However, the effects of Hsd and its molecular mechanisms on EC remain unclear. In this study, the antiproliferative, apoptotic and genomic effects of Hsd in EC and its underlying mechanisms were identified. We found that Hsd significantly suppressed the proliferation of EC cells in dose and time dependent manner. Mechanistic studies showed that Hsd could contribute apoptosis by inducing externalization of phosphatidyl serine (PS), caspase-3 activity and loss of mitochondrial membrane (MMP). Furthermore, we examined that Hsd could also significantly upregulate the expression of proapoptotic Bax subgroup genes (Bax and Bik) while downregulating the anti-apoptotic protein Bcl-2 in EC cell lines. According to GO enrichment and KEGG pathway analysis of differentially expressed genes in Hsd treated EC cells, we identified that Hsd could promote cell death via downregulation of estrogen receptor I (ESRI) that was directly related to ERK/MAPK pathway. Taken together, our study first showed that Hsd could be an antiestrogenic compound that could modulate nongenomic estrogen receptor signaling through inhibition of EC cell growth. Our findings may provide us a novel growth inhibitory agent for EC treatment after verifying its molecular mechanism with in vivo studies.Editorial Citation - WoS: 3Citation - Scopus: 4La médecine de précision en oncologie: challenges, enjeux et nouveaux paradigmes(John Libbey Eurotext Ltd, 2019) Cox, Stephanie; Rousseau-Tsangaris, Marina; Abou-Zeid, Nancy; Dalle, Stephane; Leurent, Pierre; Cutivet, Arnaud; Baran, YusufL'oncologie médicale a pris, depuis quelques années, un tournant substantiel en intégrant la dimension génomique dans la prise de décision thérapeutique. En raison de l'accès aux technologies de séquençage (exome complet, séquençage ciblé du génome, séquençage de l'ARN, ADN circulant. . .) facilité par la mise en place de plateformes de biologie moléculaire et la diminution des coûts par échantillon, la caractérisation moléculaire est devenue un outil supplémentaire à la disposition du clinicien, s'ajoutant au diagnostic histologique et immunohistochimique et aux données d'imagerie radiologique. Cette approche moléculaire a permis d'identifier de nouvelles formes nosologiques et permet, au-delà de l'aspect cognitif, de renseigner sur les altérations qui sont à prendre en compte dans les décisions thérapeutiques (biomarqueurs prédictifs, activation de voies spécifiques, mutations de résistance). C'est dans ce contexte de profond et rapide changement de pratique médicale et scientifique qu'il a été proposé de réfléchir collectivement aux nouveaux enjeux sous la forme d'un workshop à l'occasion de Biovision qui s'est tenu à Lyon, du 4 au 6 avril 2017.Article Citation - WoS: 3Citation - Scopus: 3A Minimally Invasive Transfer Method of Mesenchymal Stem Cells To the Intact Periodontal Ligament of Rat Teeth: a Preliminary Study(TÜBİTAK, 2018) Gül Amuk, Nisa; Kurt, Gökmen; Kartal Yandım, Melis; Adan, Aysun; Baran, YusufThe aim of this study was to introduce a minimally invasive procedure for mesenchymal stem cell (MSC) transfer into the intact periodontal ligament (PDL) of the molar teeth in rats. Ten 12-week-old Wistar albino rats were used for this preliminary study. MSCs were obtained from bones of two animals and were labeled with green fluorescent protein (GFP). Four animals were randomly selected for MSC injection, while 4 animals served as a control group. Samples were prepared for histological analysis, Cox-2 mRNA expression polymerase chain reaction analysis, and fluorescent microscopy evaluation. The number of total cells, number of osteoclastic cells, and Cox-2 mRNA expression levels of the periodontal tissue of teeth were calculated. The number of total cells was increased with MSC injections in PDL significantly (P < 0.001). The number of osteoclastic cells and Cox-2 mRNA expression were found to be similar for the two groups. GFP-labeled MSCs were observed with an expected luminescence on the smear samples of the PDL with transferred MSCs. The results of this preliminary study demonstrate successful evidence of transferring MSCs to intact FIX in a nonsurgical way and offer a minimally invasive procedure for transfer of MSCs to periodontal tissues.Article Citation - WoS: 9Citation - Scopus: 10An Answer To Colon Cancer Treatment by Mesenchymal Stem Cell Originated From Adipose Tissue(Mashhad University of Medical Sciences, 2018) İplik, Elif Sinem; ERtuğrul, Barış; Kozanoğlu, İlknur; Baran, YusufObjective(s): Colon cancer is risen up with its complex mechanism that directly impacts on its treatment as well as its common prevalence. Mesenchymal stem cells (MSCs) have been considered as a therapeutic candidate for conventional disease including cancer. In this research, we have focused on apoptotic effects of adipose tissue-derived MSCs in colon cancer. Materials and Methods: MSCs were obtained from adipose tissue and characterized by Flowcytometer using suitable antibodies. MSCs, HT-29, HCT-116, RKO and healthy cell line MRC5 were cultured by different seeding procedure. After cell viability assay, changes in caspase 3 enzyme activity and the level of phosphatidylserine were measured. Results: For cell viability assay, a 48 hr incubation period was chosen to seed all cells together. There was a 1.36-fold decrease in caspase 3 enzyme activity by co-treatment of RKO and MSCs in addition to 2.02-fold decrease in HT-29 and MSCs co-treatment, and 1.103-fold increase in HCT-116 and MSCs. The results demonstrated that HCT-116 led to the highest rate of apoptotic cell death (7.5%) compared with other cells. Conclusion: We suggest that MSCs might remain a new treatment option for cancer by its differentiation and repair capacity.Article Citation - WoS: 426Citation - Scopus: 470Cell Proliferation and Cytotoxicity Assays(Bentham Science Publishers, 2016) Adan, Aysun; Kiraz, Yağmur; Baran, YusufCell viability is defined as the number of healthy cells in a sample and proliferation of cells is a vital indicator for understanding the mechanisms in action of certain genes, proteins and pathways involved cell survival or death after exposing to toxic agents. Generally, methods used to determine viability are also common for the detection of cell proliferation. Cell cytotoxicity and proliferation assays are generally used for drug screening to detect whether the test molecules have effects on cell proliferation or display direct cytotoxic effects. Regardless of the type of cell-based assay being used, it is important to know how many viable cells are remaining at the end of the experiment. There are a variety of assay methods based on various cell functions such as enzyme activity, cell membrane permeability, cell adherence, ATP production, co-enzyme production, and nucleotide uptake activity. These methods could be basically classified into different categories: (I) dye exclusion methods such as trypan blue dye exclusion assay, (II) methods based on metabolic activity, (III) ATP assay, (IV) sulforhodamine B assay, (V) protease viability marker assay, (VI) clonogenic cell survival assay, (VII) DNA synthesis cell proliferation assays and (V) raman micro-spectroscopy. In order to choose the optimal viability assay, the cell type, applied culture conditions, and the specific questions being asked should be considered in detail. This particular review aims to provide an overview of common cell proliferation and cytotoxicity assays together with their own advantages and disadvantages, their methodologies, comparisons and intended purposes.Article Citation - WoS: 28Citation - Scopus: 45Biodiversity, Drug Discovery, and the Future of Global Health: Introducing the Biodiversity To Biomedicine Consortium, a Call To Action(Edinburgh University Global Health Society, 2017) Neergheen-Bhujun, Vidushi; Awan, Almas Taj; Baran, Yusuf; Bunnefeld, Nils; Chan, Kit; Dela Cruz, Thomas Edison; Egamberdieva, Dilfuza; Elsasser, Simon; Johnson, Mari-Vaughn V.; Komai, Shoji; Konevega, Andrey L.; Malone, John H.; Mason, Paul; Nguon, Rothsophal; Piper, Ross; Shrestha, Uttam Babu; Pesic, Milica; Kagansky, AlexanderLooking to nature for medicine is nothing new – we have been doing it for tens of thousands of years and although modern pharmaceutical science has come a long way from those ancient roots, nature is and will always be an important source of useful compounds and inspiration. Dismissing nature in this regard is a huge mistake as evolution is the greatest problem solver and the myriad compounds produced by the immense variety of species we share the planet with have been honed by three billion years of trial and error. However, with every bit of habitat that disappears under the plough or concrete we impoverish nature and deprive ourselves of potential medicines.Article Citation - WoS: 36Citation - Scopus: 38Effect of Molecular Architecture on Cell Interactions and Stealth Properties of Peg(American Chemical Society, 2017) Özer, İmran; Tomak, Aysel; Zareie, Hadi M.; Baran, Yusuf; Bulmuş, VolgaPEGylation, covalent attachment of PEG to therapeutic biomolecules, in which suboptimal pharmacokinetic profiles limiting their therapeutic utility are of concern, is a widely applied technology. However, this technology has been challenged by reduced bioactivity of biomolecules upon PEGylation and immunogenicity of PEG triggering immune response and abrogating clinical efficacy, which collectively necessitate development of stealth polymer alternatives. Here we demonstrate that comb-shape poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA), a stealth polymer alternative, has a more compact structure than PEG and self-organize into nanoparticles in a molecular weight dependent manner. Most notably, we show that comb-shape POEGMA promotes significantly higher cellular uptake and exhibits less steric hindrance imposed on the conjugated biomolecule than PEG. Collectively, comb-shape POEGMA offers a versatile alternative to PEG for stealth polymer-biomolecule conjugation applications.Article Citation - WoS: 5Citation - Scopus: 5Effects of Intraperitoneal Injection of Allogeneic Bone Marrow-Derived Mesenchymal Stem Cells on Bronchiolitis Obliterans in Mice Model(Tehran University of Medical Sciences, 2017) Işık, Sakine; Uzuner, Nevin; Karaman, Meral; Karaman, Özkan; Kıray, Müge; Kozanoğlu, İlknur; Bağrıyanık, Hüsnü Alper; Arıkan Ayyıldız, Zeynep; Kartal Yandım, Melis; Baran, YusufBone marrow-derived mesenchymal stem cells (BMSCs) can ameliorate a variety of lung diseases such as asthma, lung fibrosis, and acute lung injury by its anti-inflammatory and immunmodulatory effects. In this study, we developed a mouse model of bronchiolitis obliterans (BO) and evaluated the effects of the intraperitoneal administration of BMSCs on lung histopathology and cytokine levels. 25 BALB/c mice were divided into four groups; control group (Group I), BO developed and 1x106 BMSCs-injected group (Group II), non-BO, 1x106 BMSCs-injected group (Group III), and BO developed and saline-injected group (Group IV). Histological and immunohistochemical findings of the lung tissue and the migration of BMSCs to the lung were evaluated using light and confocal microscopy techniques. Confocal microscopy evaluations showed that there was no noteworthy amount of BMSCs in the lung tissue of group III while significant amount of BMSCs was detected in group II. Wall thicknesses of terminal bronchiole and periterminal bronchiolar collagen deposition were significantly lower in group II compared to the group IV (p<0.05). Furthermore, according to the immunohistochemical staining results, CD3, CD4, CD8, CD20, CD68 and neutrophil elastase positive immune cells of group II were stained more positive than group IV cells (p<0.05). IFN-ã IL-2 and TNF-á levels in bronchoalveolar lavage fluid (BALF) were significantly lower in group II compared to group IV (p<0.05). The findings of this study indicate that intraperitoneally administered BMSCs have potent effects on histopatological changes of the lung tissue and cytokine levels in the murine model of BO.