Molecular Biology and Genetics / Moleküler Biyoloji ve Genetik

Permanent URI for this collectionhttps://hdl.handle.net/11147/9

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  • Conference Object
    Citation - WoS: 1
    Differential Susceptibility To Senescence in Cart Cells Based on Co-Stimulatory Signaling
    (American Society of Hematology, 2022) Can, İsmail; Ekiz, Hüseyin Atakan; Sakemura, Reona Leo; Manriquez-Roman, Claudia; Sirpilla, Olivia; Stewart, Carli M.; Yun, Kun; Cox, Michelle J.; Ekiz, Atakan; 04.03. Department of Molecular Biology and Genetics; 04. Faculty of Science; 01. Izmir Institute of Technology
    CD19-directed chimeric antigen receptor (CART19) cells have emerged as a potentially curative immunotherapy in a subset of patients with hematological malignancies. While initial responses are impressive, the majority of responsive patients relapse within a year. Recent studies suggest that CART cells are susceptible to states of dysfunction. We aimed to study the development of T cell senescence in CART cells using similar constructs to the FDA-approved therapies, CART19-BBζ and CART19-28ζ, to determine the impact of co-stimulatory domains on CART cell senescence. We developed an in vitro model for repeated CART cell activation followed by rest to study the development of senescence and its impact on effector T cell functions. We examined CART cell immunophenotype, cell cycle regulators, and transcriptomic profile on days 0 (T cell), D8 (standard CART cell), 15 (after one activation cycle) and 22 (after two activation cycles).
  • Conference Object
    Citation - WoS: 1
    A Study of Multiple Drug Resistance Mechanisms Improved Against Bortezomib on Multiple Myeloma Cell Lines in Vitro
    (American Society of Hematology, 2007) Uyuklu, Tolga; Baran, Yusuf; Ural, A. Uğur; Sarper, Metal; Avcu, Ferit; Baran, Yusuf; Elçi, Pınar; Akar, Nejat; 04.03. Department of Molecular Biology and Genetics; 04. Faculty of Science; 01. Izmir Institute of Technology
    The most important problem in the treatment of Multiple Myeloma (MM) is the multi drug resistance (MDR) observed before and after the treatment. For this reason in MM cases an early resistance to treatment can be developed or the disease can relapsed in early period. Yet, there has been no improved drug resistance against proteazom inhibitor Bortezomib (Bor), which is used alone or with other chemotherapeutic agents in resistant or relapsed MM cases
  • Article
    Citation - WoS: 108
    Citation - Scopus: 119
    Sphingosine Kinase-1 and Sphingosine 1-Phosphate Receptor 2 Mediate Bcr-Abl1 Stability and Drug Resistance by Modulation of Protein Phosphatase 2a
    (American Society of Hematology, 2011) Salas, Arelis; Baran, Yusuf; Senkal, Can E.; Meyers-Needham, Marisa; Selvam, Shanmugam Panneer; Saddoughi, Sahar A.; Apohan, Elif; Sentelle, R. David; Smith, Charles; Gault, Christopher R.; Obeid, Lina M.; El-Shewy, Hesham M.; Oaks, Joshua; Santhanam, Ramasamy; Marcucci, Guido; Baran, Yusuf; Mahajan, Sandeep; Fernandes, Daniel; Stuart, Robert; Perrotti, Danilo; Öğretmen, Besim; 04.03. Department of Molecular Biology and Genetics; 04. Faculty of Science; 01. Izmir Institute of Technology
    The mechanisms by which sphingosine kinase-1 (SK-1)/sphingosine 1-phosphate (S1P) activation contributes to imatinib resistance in chronic myeloid leukemia (CML) are unknown. We show herein that increased SK-1/S1P enhances Bcr-Abl1 protein stability, through inhibition of its proteasomal degradation in imatinib-resistant K562/IMA-3 and LAMA-4/IMA human CML cells. In fact, Bcr-Abl1 stability was enhanced by ectopic SK-1 expression. Conversely, siRNA-mediated SK-1 knockdown in K562/IMA-3 cells, or its genetic loss in SK-1-/- MEFs, significantly reduced Bcr-Abl1 stability. Regulation of Bcr-Abl1 by SK-1/S1P was dependent on S1P receptor 2 (S1P2) signaling, which prevented Bcr-Abl1 dephosphorylation, and degradation via inhibition of PP2A. Molecular or pharmacologic interference with SK-1/S1P2 restored PP2A-dependent Bcr-Abl1 dephosphorylation, and enhanced imatinib- or nilotinib-induced growth inhibition in primary CD34+ mononuclear cells obtained from chronic phase and blast crisis CML patients, K562/IMA-3 or LAMA4/IMA cells, and 32Dcl3 murine progenitor cells, expressing the wild-type or mutant (Y253H or T315I) Bcr-Abl1 in situ. Accordingly, impaired SK-1/S1P2 signaling enhanced the growth-inhibitory effects of nilotinib against 32D/T315I-Bcr-Abl1-derived mouse allografts. Since SK-1/S1P/S1P2 signaling regulates Bcr-Abl1 stability via modulation of PP2A, inhibition of SK-1/S1P2 axis represents a novel approach to target wild-type- or mutant-Bcr-Abl1 thereby overcoming drug resistance. © 2011 by The American Society of Hematology.