Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Examination of Therapeutic Potential of Luteolin on Acute Lymphoblastic Leukemia Cells and Changes in Macromolecules(01. Izmir Institute of Technology, 2023) Çetinkaya, Melisa; Baran, YusufAcute lymphoblastic leukemia (ALL) is a genetic disease that arises from the various recurrent genetic alterations blocking the differentiation of the precursor B-and T-cells, resulting in the aberrant proliferation and survival of immature lymphoblasts within the peripheral blood and bone marrow. T-ALL is an aggressive type of ALL, and the current treatment strategies, including the high-intensity combination chemotherapy, result in different side effects which are difficult to accept or ultimately lead to the death of patients as substantial toxicity of those chemotherapeutics is known to healthy cells alongside with the cancer cells. Therefore, there is a need to identify nontoxic, costeffective, potent, and readily available treatment options for T-ALL patients. One alternative option is the flavonoids in cancer therapeutics, which are secondary metabolites of plants mainly responsible for plants' colors and flower aromas. Luteolin is an extensively researched member of the flavonoids with anticancer properties shown in various cancer types, except for the T-ALL. This study demonstrated Luteolin's time- and dose-dependent antiproliferative, cytostatic, and apoptotic effects on T-ALL cells for the first time in the literature. Also, the macromolecular changes caused in response to Luteolin treatment in T-ALL cells were examined for the first time. As a consequence, it was found that Luteolin had antiproliferative, apoptotic, and cytostatic effects on T-ALL cells, suggesting its therapeutic potential and was demonstrated to cause an increase in the lipid-to-protein ratio and the hydrocarbon chain length of the lipid acyl chains in a dose-dependent manner on T-ALL cells.Master Thesis Determination of Therapeutic Effects of Multifunctional Antibody and Peptide Micelle-Based Nanocarriers on Breast Cancer Cells(01. Izmir Institute of Technology, 2021) Abdulhadi, Nusaibah Abdulsalam Abdulhad; Baran, YusufBreast cancer is the most prevalent type of cancer and a major cause of death among women globally. Currently, many treatments are developed to reduce breast cancer death risks. Targeting therapy represents an advanced and successful approach. It provides targeting specific tumor sites by using specific ligands and modifying physicochemical characterization of nanocarriers to increase drug efficiency. In this study, we aim to determine and compare the therapeutic effects of doxorubicin (DOX)- loaded nanocarrier that was synthesized by using two properties a core cross-linked and pH sensitivity to increase drug stability and DOX releasing at the tumor site. The effects of DOX-loaded micelles (DM), HER2 targeting peptide (LTVSPWY)-conjugated-DOX-loaded micelles (DMP), and antibody (Herceptin) conjugated-DOX-loaded-micelles (DMA) on HER2 positive SKBR-3 cell line and HER2 negative MCF-10A normal epithelial breast cell line were determined by using cytotoxic, apoptotic, cytostatic, and genotoxic assays. According to the cytotoxic assay, the IC50 value of DM, DMA, and DMP were 0.71-, 0.49-, 0.34-µM, respectively. Additionally, the fluorescence image showed higher DOX uptake by SKBR-3 cells treated with DMP. According to the apoptotic assays, the mitochondrial membrane potential on SKBR-3 cells with treated DMP decreased as well as higher apoptosis and necrosis rate that was regulated by Bcl-2, Pro-Caspase-3, PARP1, Bax, Bak, and Bcl-xL. Besides, the application of DMP caused cell cycle arrest at the G2/M phase. Lastly, DNA damage was observed in response to DMP determined by comet assay. This study provides a novel and effective therapeutic option for breast cancer through using this nanocarrier system with targeting properties.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 Determination of Therapeutic Potential of Apigenin on Acute Lymphoblastic Leukemia Cells(Izmir Institute of Technology, 2019) Uzuner, Erez; Baran, YusufAcute lymphoblastic leukemia (ALL) is a hematological disorder initiating from blood-forming cells of bone marrow. ALL is characterized by the Philadelphia chromosome (Ph) arisen from a translocation between chromosome 9 and 22. This chromosome encodes BCR-ABL oncogene that is a driver regulator. BCR-ABL based studies improved tyrosine kinase inhibitors (TKI) including imatinib, dasatinib, nilotinib, and ponatinib to eliminate this disease. However, the studies on Ph+ ALL patients showed that bioactive sphingolipids have crucial roles in the elimination of the positive effects of these drugs by activating the proliferation-associated pathways, inhibition of apoptosis and increasing drug resistance of the cells treated with these drugs. In this study, therapeutic potential of apigenin, which is a natural flavonoid obtained from celery, parsley and chamomile was investigated on Ph+ ALL cell line, SD-1, and non-cancerous lung cell line Beas-2B. The cytotoxic effects of apigenin on SD-1 and Beas-2B cells were determined by MTT cell proliferation assay. The cell viability analyses on SD-1 cells were conducted by Trypan blue dye exclusion assay following apigenin treatment. Cell cycle and apoptosis analyses including Annexin V/PI-dual staining and JC-1 dye-based mitochondrial membrane potential were examined by flow cytometry. Expression levels of bioactive sphingolipids were determined by RT-PCR and western blot. The cytotoxic analyses indicated that apigenin selectively inhibits the expression of SD-1 cells whereas the IC50 value of apigenin for SD-1 cells has the anti-apoptotic roles in Beas-2B cells. SD-1 cells experience cell death via apoptosis-related pathways and apigenin might arrest the cells at G2/M phases. Indeed, the changes in the expression levels of bioactive sphingolipids genes indicated their roles in apigenin-induced apoptosis in SD-1 cells. This study investigated the cytotoxic and apoptotic effects of apigenin on SD-1 cells and the roles of apigenin in bioactive sphingolipid metabolism for the first time.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 Synergistic Apoptotic Effects of Bortezomib and Methylstat Inhibitor on Different Multiple Myeloma Cell Lines(Izmir Institute of Technology, 2015) Kacı, Fatma Necmiye; Baran, Yusuf; Saydam, GürayMultiple myeloma is one of the common hematological malignancies that affects plasma cells. Bortezomib, proteasome inhibitor, is an anticancer agent used for the treatment of multiple myeloma while methylstat is a demethylase inhibitor having anticancer potential. In this study, we investigated antiproliferative and apoptotic effects of methylstat alone or in combination with bortezomib. We also examined the genes involved in methylstat induced apoptosis. Cytotoxic effects of bortezomib and methylstat on U266 and ARH77 cells were demonstrated by MTT cell proliferation assay. To understand the apoptotic effects of these agents, loss of mitochondrial membrane potential was investigated by JC-1 method while phosphatidylserine localization was investigated by Annexin V assay. Cell cycle analysis in response to Bortezomib and Methylstat alone or in their combination were measured by flow cytometry. Changes in expression profiles of 84 genes underlying apoptosis, cell cycle control, DNA damage repair, and invasion and metastasis in response to Methylstat were determined by PCR Array. Our results demonstrated that both bortezomib and methylstat have antiproliferative and aoptotic effects in a time and dose dependent manner. Combination of bortezomib and methylstat induced apoptosis significantly as compared to any agent alone. In conclusion, we suggest methylstat as candidate agent for the treatment of MM after in vivo analyses.Master Thesis Expression Levels of Jak/Stat Signaling Genes in Newly Diagnosed, Drug Sensitive and Resistant Chronic Myeloid Leukemia Patients(Izmir Institute of Technology, 2014) Kiraz, Yağmur; Baran, Yusuf; Saydam, GürayJAK/STAT signaling pathway has a role in transmission of information carried by cytokines, from outside of the cell to the nucleus. The system is run by the proteins known as Janus kinases (JAK) located on the cell membrane and STAT proteins acting as signal transducer and activator of transcription. JAK proteins activated by cytokines, phosphorylates and initiates the dimerization of STATs, which become active, move into nucleus and regulate expression of target genes. Previous studies demonstrated that there is overexpression of JAK/STAT genes in various types of cancer. The aim of this study is to examine the relationship between expression levels of JAK/STAT genes and clinical outcome of chronic myeloid leukemia (CML) patients. In this study expression levels of Jak/STAT pathway genes were analyzed in 23 different patients (1 patient responded positively, 1 only imatinib and 1 both imatinib and nilotinib resistant patients, 1 patient lost molecular response, 5 imatinib treated, and 14 newly diagnosed CML patients). The results showed that expression levels of Jak3, STAT1, STAT2, STAT3, STAT4 and STAT5A genes were overexpressed in TKI resistant patients. Expression levels of STAT5B, Jak1, Jak2 and Tyk2 genes were higher in newly diagnosed patients compared to resistant patients while STAT1 was lower in imatinib-treated patients. It was demonstrated for the first time that there is a relation between the clinical outcome of CML patients and expression levels of JAK-STAT genes that could make this signaling pathway a new target for more effective treatment of CML.Master Thesis The Involvement of Ceramide Metabolizing Genes and Their Products in Docetaxel Induced Apoptosis in Human Prostate Cancer Cells(Izmir Institute of Technology, 2009) Başsoy, Esen Yonca; Baran, YusufPatients diagnosed with prostate cancer initially respond to androgen ablation therapy with tumor cells undergoing apoptosis, but then the patients relapse in time and develop metastatic, androgen independent prostate cancer. Docetaxel has been widely used for treatment of patients with advanced metastatic prostate cancer. The sphingolipid, ceramide, is a lipid second messenger that mediates a lot of functions as regulation of cell growth, proliferation, differentiation, senescence and apoptotic responses in various cancer cells. The enzyme, glucosylceramide synthase (GCS) is responsible for bioactivation of the proapoptotic mediator ceramide to antiapoptotic glucosylceramide. Likewise, sphingosine kinase-1 (SK-1) transforms apoptotic ceramide to antiapoptotic sphingosine 1-phosphate. Emerging results indicate that GCS and SK-1 are overexpressed in resistant cancer cell lines and cancerous tissue samples of patients. Moreover apoptosis and inhibition of cell proliferation and survival are induced by intracellular ceramide levels including enhancement in de novo ceramide production, exogenous delivery of cell permeable ceramide and inhibition of ceramide metabolism by affecting GCS and SK-1. In this study, we applied exogenous ceramide and inhibitors of GCS and SK-1 in combination with docetaxel for sensitizing androgen independent prostate cancer cells to chemotherapy and provide their effectively utilization with minimizing side effects of the drugs. The de novo generation of ceramide is regulated by the genes (LASS1-6) in mammalian cells. Therefore in this study, we examined the possible roles of the ceramide/S1P and ceramide/GS by examining expression levels of GCS, SK-1 and LASS1,2,4,5,6 which can play important roles to overcome androgen independent.Master Thesis The Mechanisms Responsible for Nilotinib Resistance in Human Chronic Myeloid Leukemia Cells(Izmir Institute of Technology, 2010) Camgöz, Aylin; Baran, Yusuf; Baran, YusufMultidrug resistance remains a significant obstacle to successful chemotherapy. The ability to determine the possible resistance mechanisms and surmount the resistance is likely to improve chemotherapy. Nilotinib is a very effective drug in the treatment of sensitive or Imatinib resistant patients. Although very successful hematologic and cytogenetics responses have been obtained in Nilotinib-treated patients, in recent years resistance cases were observed. The main objective of the project is to understand the mechanisms underlying multidrug resistance to Nilotinib to provide new targets for the treatment of chronic myeloid leukemia (CML). In this study, continuous exposure of cells to step-wise increasing concentrations of Nilotinib resulted in the selection of cells resistant to 50 nM Nilotinib and referred to as K562/NIL-50. Expression analyses of BCR-ABL gene demonstrated BCR-ABL was upregulated in resistant cells as compared to parental sensitive cells. However, nucleotide sequence analyses of ABL kinase gene revealed that there was no mutation in Nilotinib binding region of the gene in resistant cells. There was also an increase in expression levels of MRP1 gene in resistant cells, which transports the toxic substances outside of cells. Besides, Bax, which is one of the apoptosis inducing genes, was dowregulated in resistant cells. In addition to this, in resistant cells, while GCS and SK-1 genes were overexpressed, decrease in expression levels of LASS1 gene was observed. In conclusion, we determined mechanisms involved in Nilotinib resistance in CML in vitro. Targeting this mechanisms, besides inhibition of BCR-ABL may be a good way of treatment of CML.Master Thesis Activated Signaling Pathways and Apoptotic Mechanisms in Resveratrol Applied Chronic Myeloid Leukemia Cells and the Involvement of Ceramide Metabolizing Genes on These Mechanisms(Izmir Institute of Technology, 2010) Kartal Yandım, Melis; Baran, Yusuf; Baran, YusufResveratrol, an important phytoalexin in many plants, has cytotoxic effects on several cancer cells. Ceramide is a significant sphingolipid which affects many signaling pathways regulating cell senescence, migration, and cell cycle arrest. Intracellular ceramide level is balanced by glucosylceramide synthase (GCS), the converter of ceramide to glucosylceramide, and sphingosine kinase-1 (SK-1) that convert ceramide to sphingosine 1-phosphate (S1P). Ceramide functions as an apoptotic molecule whereas glucosylceramide S1P function as anti-apoptotic. An important cell-permeable analogue of natural ceramides, C8:ceramide, increases intracellular ceramide levels significantly, while 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) and SK-1 inhibitor increase accumulation of ceramides by inhibiting GCS and SK-1, respectively. Chronic myelogenous leukemia (CML), a hematological disorder, results from the generation of BCR/ABL oncogene. In this study, we examined the roles of ceramide metabolizing genes in resveratrol-induced apoptosis, and the expression profiles of 84 genes underlying apoptosis, cell cycle control, DNA damage repair, and invasion and metastasis in human K562 CML cells treated with resveratrol. There were synergistic cytotoxic and apoptotic effects of resveratrol with coadministration of C8:ceramide, PDMP and SK-1 inhibitor. We observed significant increases in expression levels of LASS genes, and decreases in expression levels of GCS and SK-1 in K562 cells in response to increasing concentrations of resveratrol. There were also significant increases in the expression levels of SERPINB5, FAS, TNFRSF, MTSS that are related with tumor suppression, and decreases in Myc expression. Our data, in total, showed for the first time that resveratrol might kill CML cells through increasing intracellular generation and accumulation of apoptotic ceramides.