Aydın, Muammer Merve2016-04-252016-04-252015-082015-0811-09-2015http://hdl.handle.net/11693/28980Cataloged from PDF version of thesis.Includes bibliographical references (leaves 90-122).Thesis (Ph. D.): Bilkent University, Department of Molecular Biology and Genetics, İhsan Doğramacı Bilkent University, 2015.In our previous studies on liver regeneration, we demonstrated that following partial hepatectomy (PH) FLT3 contributes cellular proliferation that provides a basis for liver regeneration. Moreover, we were able to suggest a potential role for FLT3 in hepatocarcinogenesis for the first time. Therefore, we further investigated the effect of FLT3 inhibition on the invasiveness and aggressiveness of hepatocarcinogenesis. Our findings were parallel to our previous results supporting the contribution of FLT3 in hepatocarcinogenesis. Thus, we are presenting FLT3 as a novel candidate for the diagnosis and treatment of HCC. We also focused on liver fibrosis since it is the initial wound healing response generated by the liver against damaging insults. Liver fibrosis is a reversible process, but if its progression is not prevented it might turn into cirrhosis and end up with HCC. Toll-like receptors (TLRs) have been reported to contribute to this fibrotic response generated in the liver resulting from the activating effects of various danger ligands. We show that using suppressive oligodeoxynucleotide (ODN) A151 might control TLR dependent immune activation that takes place after the induction of liver fibrosis. Our results show that suppressive ODN A151 administration has a negative effect on αSMA expression and collagen accumulation, which are the major events taking place during liver fibrogenesis. Additionally, this suppressive effect of suppressive ODN A151 was revealed to be systemic. Splenocytes of suppressive ODN A151 administered mice showed different cytokine secretion patterns and antigen presenting cell (APC) function after being stimulated with various TLR ligands. These findings suggested us that using suppressive ODN might be a rational and novel approach to control the liver fibrogenesis and even prevent its progression into cirrhosis reducing the number of liver transplantations needed by the patients. Finally, we focused on HSPs, some of which are also known to activate TLR signaling. Additionally, HSP27 has a role in actin cytoskeleton organization and controlling cellular motility, which are among the events that take place in liver fibrogenesis. Therefore, for the first time we present preliminary data on the potential role of HSP27 in liver fibrosis and quercetin treatment as a therapeutic approach due to its HSP27 and αSMA expression changing effects.xxv, 144 leaves : graphics, tables.Englishinfo:eu-repo/semantics/openAccessLiverLiver cancerHepatocellular carcinomaLiver fibrosisFLT3TLRsSuppressive ODN A151HSPsHSP27QuercetinThesisB151230