Browsing by Subject "TBK1"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Open Access Identifying TBK1-specific roles in colorectal cancer(Bilkent University, 2022-06) Bagheralmoosavi, ServinColorectal cancer (CRC) is the second most lethal cancer type, with a high incidence rate among adults. The CRC is a highly heterogenic disease with a high rate of mutations in different molecular pathways. Moreover, resistance to standard treatment options is seen frequently among CRC patients. Therefore, a better understanding of the mechanisms behind the initiation, progression, and drug resistance allows us to increase the life quality of CRC patients. TBK1 is a kinase protein with central roles in most cellular signaling pathways. This protein has been reported to be an oncogene in some cancer types. However, the role of TBK1 in colorectal cancer is not yet established. In this study, we generated stable TBK1 knockdown CRC cell lines and mainly focused on the role of TBK1 in colorectal cancer pathogenesis. Upon TBK1 depletion in CRC, we observed increased cell proliferation and migration in vitro. The role of TBK1 in cell proliferation is further confirmed in xenograft models in vivo. Moreover, a shift in EMT and resistance to Gefitinib, an EGFR inhibitor, is indicated in TBK1 knockdown cells. TBK1 is also diminished in our Gefitinib-resistant CRC cell lines, suggesting a role for this protein in drug resistance. The findings of this study suggest a tumor-suppressive role for TBK1 in CRC. Hence, further investigations on the mechanisms behind this tumor-suppressive role of TBK1 in CRC will pave the way for developing novel therapeutic options for CRC treatment.Item Open Access Leishmania kinetoplast DNA contributes to parasite burden in infected macrophages: Critical role of the cGAS-STING-TBK1 signaling pathway in macrophage parasitemia(Frontiers Media S.A., 2022-11-02) Yilmaz, Ismail Cem; Dunuroglu, Emre; Ayanoglu, Ihsan Cihan; Ipekoglu, Emre Mert; Yıldırım, Muzaffer; Girginkardesler, Nogay; Ozbel, Yusuf; Toz, Seray; Ozbilgin, Ahmet; Aykut, Gamze; Gursel, IhsanLeishmania parasites harbor a unique network of circular DNA known as kinetoplast DNA (kDNA). The role of kDNA in leishmania infections is poorly understood. Herein, we show that kDNA delivery to the cytosol of Leishmania major infected THP-1 macrophages provoked increased parasite loads when compared to untreated cells, hinting at the involvement of cytosolic DNA sensors in facilitating parasite evasion from the immune system. Parasite proliferation was significantly hindered in cGAS- STING- and TBK-1 knockout THP-1 macrophages when compared to wild type cells. Nanostring nCounter gene expression analysis on L. major infected wild type versus knockout cells revealed that some of the most upregulated genes including, Granulysin (GNLY), Chitotriosidase-1 (CHIT1), Sialomucin core protein 24 (CD164), SLAM Family Member 7 (SLAMF7), insulin-like growth factor receptor 2 (IGF2R) and apolipoprotein E (APOE) were identical in infected cGAS and TBK1 knockout cells, implying their involvement in parasite control. Amlexanox treatment (a TBK1 inhibitor) of L. major infected wild type cells inhibited both the percentage and the parasite load of infected THP-1 cells and delayed footpad swelling in parasite infected mice. Collectively, these results suggest that leishmania parasites might hijack the cGAS-STING-TBK1 signaling pathway to their own advantage and the TBK1 inhibitor amlexanox could be of interest as a candidate drug in treatment of cutaneous leishmaniasis. Copyright © 2022 Yilmaz, Dunuroglu, Ayanoglu, Ipekoglu, Yildirim, Girginkardesler, Ozbel, Toz, Ozbilgin, Aykut, Gursel and Gursel.