Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Investigation of Anticancer Properties of Novel Mdm2 Inhibitors(Izmir Institute of Technology, 2021) Özdemir, Sefayi Merve; Çağır, AliCancer is one major disease causing death worldwide. Current cancer treatments are not %100 effective to cure for patients, yet. Thereby, the synthesis and discovery of new therapeutics have been important to improve the survival period of the cancer patients. There are many strategies for synthesis of cancer therapeutics. One of the most important strategy for cancer treatment is the reactivation of p53. MDM2 is a negative regulator of p53 in cell, because it causes the inactivation of p53. In this thesis, the anticancer and MDM2 inhibitory properties of ezetimibe, desfluoro ezetimibe and intermediates during ezetimibe synthesis (named as SM2-9) and a side product from the synthesis of benidipine (named as SM1) on prostate cancer (LnCAP, wild-type p53), breast cancer (MCF7, wild type p53) and uterus cancer (HeLa, wild type nonfunctional p53) cells were investigated. For this purpose, the cytotoxic, cytostatic and apoptotic properties of these compounds were determined. Compounds SM2, SM3, SM4 and SM6 demonstrated cytotoxic effects, whereas compounds SM5, SM8 and SM9 had cytostatic effects on three cells. Compound SM7 had no effect on these cells, up to 100 μM concentration. Compounds SM1 had cytostatic effect on MCF7 cells, but it showed no activity on other cells. Compounds SM8 and SM9 had strong cytostatic activity. Thus, the apoptotic properties of these compounds were examined by caspases 3/7 activation and Annexin-V FITC assays. Besides, MDM2 inhibitor profiles of these compounds were investigated by fluorescence polarization assay. This study provides novel and potential molecules for drug discovery in cancer treatmentMaster Thesis Investigating Oncogenic Role of Sema6d in Breast Cancer Cells(Izmir Institute of Technology, 2019) Günyüz, Zehra Elif; Yalçın Özuysal, ÖzdenBreast cancer, the most commonly diagnosed cancer type and the leading cause of cancer-associated deaths, is the major health issue among women worldwide. In many cancer types, the expression of the semaphorins and their receptors such as plexins and neuropilins are dysregulated. SEMA6D is a member of class-6 family transmembrane semaphorin proteins and acts through Plexin-A1 receptor. It was previously shown that overexpression of SEMA6D in breast cancer cell line MCF-7 leads to a reduction in proliferation and an increase in migration. On the other hand, in the MDA-MB-231 breast cancer cell line, overexpression of SEMA6D had no significant effect on proliferation but enhanced migration. In this study, we aimed to analyze the effects of SEMA6D overexpression in normal breast cell line MCF10A and investigate the invasive behavior and transformation capacity of SEMA6D overexpressing breast cancer cell lines. We demonstrated that overexpression of SEMA6D leads to elevated proliferation, viability and migration in MCF10A cells, whereas it did not trigger their anchorage-independent growth. On the other hand, MDA-MB-231 and MCF7 cells stably expressing SEMA6D showed reduced colony formation in the soft-agar assay. Furthermore, the invasiveness of MDA-MB-231 cells was elevated with SEMA6D overexpression, whereas SEMA6D overexpression did not stimulate the invasiveness of MCF-7 cells through matrigel microenvironment, whereas slightly trigger invasion through bone microenvironment. In conclusion, SEMA6D overexpression has cell-specific effects on breast cancer. The exact role of SEMA6D in breast cancer development remains undefined and must be further investigated.Master Thesis Determination of Therapeutic Potential of Luteolin for Acute Lymphoblastic Leukemia Cells(Izmir Institute of Technology, 2019) Gürler, Sevim Beyza; Baran, YusufAcute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by increased level of immature lymphoblasts in bone marrow and peripheral blood. The developments of lymphoblasts are genetically/epigenetically inhibited. One of the most common genetic abnormalities in ALL is BCR/ABL translocation which regulates the several pathways related to proliferation, anti-apoptotic and drug resistance through its aberrant tyrosine kinase activity. Although the current treatment strategies include targeting BCR/ABL via tyrosine kinase inhibitors; complete remission, overall survival and mortality of Ph+ ALL patients are still worse as compared to Ph- ALL patients. Therefore, new strategies combined with current treatments are needed for Ph+ ALL patients who are qualified as high risk group of ALL. Different studies showed thatluteolin has anti-cancer and anti-tumor effects on wide range cancer types including breast, colon, lung cancer except ALL in both in vitro and in vivo. In this study, the dose and time dependent cytotoxic, apoptotic and cytostatic effects of luteolin on Philadelphia chromosome +ALL cells were determined for the first time. Besides, the effect of luteolin on cell growth and proliferation of two different healthy cell lines was shown. Moreover, the effect of luteolin on bioactive sphingolipids genes which regulate the several pathways including cell proliferation, apoptosis, drug resistance and senescence in cell was determined in Ph positive ALL cells for the first time. As a consequence, luteolin has cytotoxic, apoptotic and cytostatic effects on Ph positive ALL cells and bioactive sphingolipids genes are regulated in this therapeutic potential by luteolin.Master Thesis Analysis of Tnfrsf10b-As Long-Noncoding Rna's Effects on Various Cancer Cell Properties(Izmir Institute of Technology, 2019) Alkan, Ayşe Hale; Akgül, BünyaminLong noncoding RNAs (lncRNAs) being longer than 200 nucleotides constitute a different class of RNA molecules. Several studies indicated that they have regulatory role in cellular processes including cancer development. Some of them have exclusively high expression in particular cancer types and regulate certain cancer cell properties. This renders them potential biomarker or therapeutic target in cancer. In this study, effects of a candidate lncRNA TNFRSF10B-AS and lncCAMTA1 on cancer cell properties were investigated. Candidate lncRNAs from Doxorubicin, Fas mAB, TNF-alpha and Cisplatin treated HeLa cell line were chosen and their expression level was measured in different cell lines including healthy (BEAS2B and MCF10A), metastatic (H1299 and MDA-MB- 231) and non-metastatic cell lines (A549 and MCF-7) by qPCR. From a few candidates lncCAMTA1 and TNFRSF10B-AS were selected for further analysis. qPCR results obtained from comparison of different cancer cell lines showed that their expression differs at least in one comparison of cell lines. TNFRSF10B-AS silencing decreased proliferation of HeLa cells. lncCAMTA1 was silenced or overexpressed in HeLa cells but phenotypic effect couldn’t be detected by apoptosis and cell proliferation assay. Additionally, phenotypic effect also couldn’t be observed in other cell lines when TNFRSF10B-AS was silenced.Master Thesis Desing and Synthesis of Bodipy Based Photosensitizers for Photodynamic Therapy(Izmir Institute of Technology, 2019) Dartar, Suay; Emrullahoğlu, Mustafa; Emrullahoğlu, MustafaPhotodynamic therapy is a promising modality for the non-invasive treatment of several cancerous and non-cancerous diseases. PDT is more preferable than other therapies due to its low damage to non-targeted tissues and its controllable characteristics. The therapy involves the activation of a photosensitizer under light illumination to generate singlet oxygen which is the cytotoxic agent employed against the cancerous tissues. Thus, there is currently a great effort to develop various photosensitizers. Among these, BODIPY based photosensitizers are distinguished due to certain characteristics, including excellent photostability, high extinction coefficients and high resistance to photobleaching. In this study, we aimed to synthesize and develop new BODIPY based photosensitizers for the use of photodynamic therapy agents. BODIPY skeleton was devised using the dibromoethylene unit from the 2,6-positions in order to enhance the π-conjugation system for red shift to longer wavelengths resulting in a deep penetration of tissue. Heavy atoms such as bromine were introduced to the BODIPY core to ensure the transition from singlet states to triplet states via intersystem crossing for the generation of singlet oxygen. Photophysical properties and spectroscopic measurements of photosensitizers were performed successfully. Finally the photodynamic activities of photosensitizers in cancerous cells were also investigated.Master Thesis Determination of Therapeutic Effects of Multifunctional Micelle-Based Nanocarriers on Breast Cancer Cells(Izmir Institute of Technology, 2019) Ulu, Gizem Tuğçe; Baran, YusufBreast cancer is the most common and frequent cause of death among women composed to all types of cancer. Current treatment protocols do not provide complete cure or selective drug delivery while targeted therapy can provide an important avenue for successful treatment of breast cancer. In this study, therapeutic effects of drug-conjugated nanocarrier system with enhanced stability and double moiety pH-sensitivity on breast cancer (SKBR-3- HER-2- positive), normal breast epithelial (MCF-10A, HER-2-negative) and chronic myeloid leukemia (K562, HER-2-negative) cells were determined. With this approach, SKBR-3 cells were targeted by single nanocarriers having selectivity with unused peptide ligand (HER-2), stability with cross-linking of core moiety, and cleavage by two sites of pHeffect and drug release properties. After physicochemical characterization of micellebased nanocarriers, cytotoxic, apoptotic and cytostatic effects of doxorubicin conjugated micelles were determined. Doxorubicin conjugated micelles with HER-2 peptide (DOX-HER-2-NCs) had more cytotoxic effects on HER-2 positive cells. Additionally, intracellular amounts of doxorubicin is higher in SKBR-3 cells with applied DOX-HER-2-NCs as determined by fluorescence imaging. The apoptosis rate was increased on SKBR-3 at 50% cell growth inhibition (IC50) as determined by Annexin-V/Propidium iodide double staining. However, there was not any significant change in loss of mitochondrial membrane potential. Additionally, DOX-HER-2-NCs resulted in cell cycle arrest at G2/M-phase in response to IC50 value. Besides, protein level of Bcl-2 did not change while protein level of Bax and Caspase-3 were increased as determined by Western Blotting. This project provides novel and more effective treatment of breast cancer by using multifunctional properties of nanocarriers.Master Thesis Cyr61-Notch Interaction During Epithelial-To Transition, Migration and Invasion in Breast Cancer Cells(Izmir Institute of Technology, 2017) İlhan, Mustafa; Yalçın Özuysal, ÖzdenNotch signaling is one of the major pathways involved in development and tumorigenesis. Activated Notch is correlated with increased migration, invasion and epithelial-to-mesenchymal-transition (EMT) in breast cancer. However, mechanism of Notch-mediated cancer progression is poorly understood. CYR61 is a secreted protein and its upregulation is also related to increased breast tumorigenesis and EMT. Microarray analyses revealed that CYR61 was differentially expressed in response to Notch activation in breast epithelial cells. We hypothesized that CYR61 is a downstream mediator of Notch during EMT, migration and invasion. To test whether Notch requires CYR61 during EMT, migration and invasion, two complementary approaches were followed: (i) CYR61 expression was silenced by using shRNA in MCF10A epithelial breast cell line in the presence of Notch activation, (ii) CYR61 was over-expressed in MDA-MB-231 cancer breast cell line in the absence of Notch activity. Then, expression of EMT markers was analyzed in mRNA and protein levels via RT-qPCR and immuno-blotting, respectively. Migration and invasion ability of cells were investigated by wound healing assay and a lab-on-a-chip-system, respectively. Here, it was shown that CYR61 inhibition decreased Notch-induced EMT, migration and invasion of MCF10A and CYR61 overexpression in the absence of Notch activity partially rescued Notch-mediated invasion in MDA-MB-231 cell lines. Our findings suggest that CYR61 may act in downstream of Notch and is regulated by Notch. When we consider importance of CYR61 in Notch-induced EMT and cancer progression, targeting CYR61 may hold promise to develop novel strategies for treatment of breast cancer in early stages.Master Thesis Interactions of Cancer Cells and Macrophages on the Egf-Egfr Axis: Chemotaxis, Haptotaxis or Direct Contact?(Izmir Institute of Technology, 2017) Önal, Sevgi; Pesen Okvur, Devrim; Bulmuş Zareie, Esma VolgaBreast cancer cells (BCC) and macrophages are known to interact via epidermal growth factor (EGF) produced by macrophages and colony stimulating factor-1 (CSF-1) produced by BCC. Despite contradictory findings, this interaction is perceived as a paracrine loop. Yet, the underlying mechanism of interaction remains unclear. Here, we investigated interactions of BCC with macrophages in 2D and 3D. BCC did not show chemotaxis to macrophages in custom designed 3D cell-on-a-chip devices, which was in agreement with ELISA results showing that macrophage-derived-EGF was not secreted into macrophage-conditioned-medium. Live cell imaging of BCC in the presence and absence of iressa showed that macrophages but not macrophage-derivedmatrix modulated adhesion and motility of BCC in 2D. 3D co-culture experiments in matrigel and collagen showed that BCC changed their multicellular organization in the presence of macrophages. In custom designed 3D co-culture cell-on-a-chip devices, macrophages reduced and promoted migration of BCC in matrigel and collagen, respectively. Furthermore, adherent but not suspended BCC endocytosed EGFR when in contact with macrophages. Collectively, our data revealed that macrophages showed chemotaxis towards BCC-derived-CSF-1 whereas BCC required direct contact to interact with macrophage-derived-EGF. We propose that the interaction between cancer cells and macrophages is a paracrine-juxtacrine loop of CSF-1 and EGF, respectively.Master Thesis Comparison of Connnexin32 Expression and Function Between Mcf10a Normal Breast and Mda-Mb Breast Cancer Cell Lines(Izmir Institute of Technology, 2017) Adak, Aslı; Meşe Özçivici, GülistanBreast cancer is one of the most prominent cancer-related deaths among females. Among many molecules, connexins have role in breast cancer. Gap junctions, formed from connexins (Cx), facilitate intercellular communication between adjacent cells. Different connexins were expressed during different stages of breast cancer. Cx32 was found both in normal pre-menopausal and tumor breast tissue samples. In lymph node metastases, elevated Cx32 level was observed compared to primary cancer. However, the role of Cx32 in breast cancer is not known but its elevation in lymph node metastasis may indicate its diverse functions in breast cancer. To verify this, in MCF10A and MDA-MB-231 cell lines, Cx32 was overexpressed. The protein localization was compared with immunostaining. In MDAMB- 231 cells, Cx32 localized in nucleus and cytoplasm, although in MDA-MB-231 Cx32-EGFP cells, Cx32 localized mostly in the cytoplasm. In MCF10A cells, Cx32 localized in nucleus, whereas Cx32 formed gap junctional plaques between MCF10A Cx32-EGFP cells. By Cx32 overexpression, gap junction coupling increased in MCF10A cells significantly, although it did not change in MDA-MB-231 cells. In both cells, hemichannel activity was not altered with Cx32 overexpression. The effects of Cx32 overexpression on cell viability demonstrated a significant decrease in MCF10A cells and an increasing trend in MDA-MB-231 cells. Furthermore, the percentage of G1 phase decreased, G2 and S phases increased in MDA-MB-231. However, Cx32 overexpression did not alter cell cycle profile of MCF10A significantly. Determination of the differential role of Cx32 in different stages of breast cancer may help to understand its diagnostic and/or therapeutic potential.Master Thesis Antiproliferative Properties of 2'-alkoxymethyl Substituted Klavuzon Derivatives(Izmir Institute of Technology, 2017) Yıldız, Mehmet Salih; Pesen Okvur, Devrim; Çağır, Ali; Çağır, Ali; Pesen Okvur, DevrimOne of the main objectives of studies on anticancer agents is that the agent is expected to show a high cytotoxic activity on cancer cells and show a less cytotoxic effect on the contrary in healthy cells or never show cytotoxic activity. (R)- goniothalamin, isolated from the Goniothalamus plant, is a styryl lactone and has been found to have a selective antiproliferative property on cancer cells in studies conducted. The Michael acceptor feature in the structure of goniothalamin is thought to be covalently bonded to the nucleophilic side chains of the enzymes and show activity in this way. In previous studies, it has been shown that 1-naphthyl substituted 5,6-dihydro- 2H-pyran-2-one derivatives and 4'-methyl klavuzon derivatives exhibit higher cytotoxic activity on cancer cells than goniothalamin. In this study, antiproliferative properties of newly synthesized 2'-alkoxymethyl substituted klavuzon derivatives have been examined and MIA PaCa-2 pancreatic cancer cell lines and HPDEC pancreatic healthy cell lines were used. MTT cell viability tests were performed at the first step of this study. As a result of this study, it has been observed that the 2'-isobutoxymethylklavuzon derivative has selective cytotoxic activity on the MIA PaCa-2 cell line. It showed activity at lower concentrations than goniothalamin. Cytotoxic activities of the compounds are associated with the size of the R group at position 2’-. Methoxymethyl substituted the worst selective activity among these compounds whereas isobutoxy derivative the best selective one. In the second stage of the study, the inhibition on topoisomerase I enzyme was studied. The 2'-alkoxymethyl klavuzon derivatives were found to have Topo I enzyme inhibition properties depending on concentration and time manner. The study continued with choices methoxy and isobutoxy derivatives and these two compounds caused an arrest at G1 phase and DNA damage. Also, isobutoxy derivative induced apoptosis in the MIA PaCa-2 pancreatic cancer cell lines.