Scopus İndeksli Açık & Kapalı Erişimli Yayınlar
Permanent URI for this communityhttps://hdl.handle.net/11727/10752
Browse
4 results
Search Results
Item Editorial: Cell Death and Targeted Cancer Therapies(2022) Bagci-Onder, Tugba; Kutuk, Ozgur; Chonghaile, Triona Ni; Knippschild, Uwe; 000829492900001Item Hedgehog Signal Defect Leading to Familial Exudative Vitreoretinopathy-Like Disease and Gastrointestinal Malformation(2022) Keskek, Nedime Sahinoglu; Akkoyun, Imren; Temiz, Abdulkerim; Kutuk, Ozgur; https://orcid.org/0000-0001-8544-103X; https://orcid.org/0000-0002-2860-7424; https://orcid.org/0000-0001-9854-7220; 35770050; T-4258-2017; AAK-7713-2021Objectives: The aim of the study was to present a new generic association presenting with gastrointestinal tract malformations (GTMs) and familial exudative vitreoretinopathy (FEVR)-like disease and review the genetics of Hedgehog signaling. Materials and Methods: Three neonates were diagnosed with FEVR-like retinal vascular disease upon routine ophthalmological examination during hospitalization in the neonatal surgical intensive care unit for GTMs. Generic analysis of the neonates was performed. Results: Gestational age of the neonates was 39, 38, and 39 weeks and birth weights were 3,500, 3,600, and 3,300 grams, respectively. All six eyes of the three infants were treated by laser photocoagulation. Recurrence was not seen in any of the eyes. Genetical analysis of all the neonates diagnosed with FEVR-like disease revealed defects in the Hedgehog pathway. Conclusion: FEVR is a genetically well-defined retinal vascular disease. The current study is the first to show an association between FEVR-like retinal vascular disease and GTMs. This study demonstrates the importance of the Hedgehog pathway in retinal vascular and gut development.Item Mitochondrial estrogen receptors alter mitochondrial priming and response to endocrine therapy in breast cancer cells(2021) Karakas, Bahriye; Aka, Yeliz; Giray, Asli; Temel, Sehime Gulsum; Acikbas, Ufuk; Basaga, Huveyda; Gul, Ozgur; Kutuk, Ozgur; 34294688Breast cancer is the most common cancer with a high rate of mortality and morbidity among women worldwide. Estrogen receptor status is an important prognostic factor and endocrine therapy is the choice of first-line treatment in ER-positive breast cancer. However, most tumors develop resistance to endocrine therapy. Here we demonstrate that BH3 profiling technology, in particular, dynamic BH3 profiling can predict the response to endocrine therapy agents as well as the development of acquired resistance in breast cancer cells independent of estrogen receptor status. Immunofluorescence analysis and subcellular fractionation experiments revealed distinct ER-alpha and ER-beta subcellular localization patterns in breast cancer cells, including mitochondrial localization of both receptor subtypes. shRNA-mediated depletion of ER-beta in breast cancer cells led to resistance to endocrine therapy agents and selective reconstitution of ER-beta in mitochondria restored sensitivity. Notably, mitochondria-targeted ER-alpha did not restore sensitivity, even conferred further resistance to endocrine therapy agents. In addition, expressing mitochondria-targeted ER-beta in breast cancer cells resulted in decreased mitochondrial respiration alongside increased total ROS and mitochondrial superoxide production. Furthermore, our data demonstrated that mitochondrial ER-beta can be successfully targeted by the selective ER-beta agonist Erteberel. Thus, our findings provide novel findings on mitochondrial estrogen signaling in breast cancer cells and suggest the implementation of the dynamic BH3 technique as a tool to predict acquired endocrine therapy resistance.Item Kinome-wide RNAi screening for mediators of ABT-199 resistance in breast cancer cells identifies Wee1 as a novel therapeutic target(2021) Aka, Yeliz; Acikbas, Ufuk; Kutuk, Ozgur; 34171479Antiapoptotic and proapoptotic BCL-2 protein family members regulate mitochondrial apoptotic pathway. Small molecule inhibitors of antiapoptotic BCL-2 proteins including BCL-2-specific inhibitor ABT-199 (Venetoclax) are in clinical development. However, the efficiency of ABT-199 as a single agent in solid tumors is limited. We performed a high-throughput RNAi kinome screen targeting 691 kinases to identify potentially targetable kinases to enhance ABT-199 response in breast cancer cells. Our studies identified Wee1 as the primary target kinase to overcome resistance to ABT-199. Depletion of Wee1 by siRNA-mediated knockdown or inhibition of Wee1 by the small molecule Wee1 inhibitor AZD1775 sensitized SKBR3, MDA-MB-468, T47D and CAMA-1 breast cancer cells to ABT-199 along with decreased MCL1. BH3-only proteins PUMA and BIM functionally contribute to apoptosis signaling following co-targeting BCL-2 and Wee1. Suppression of Wee1 function increased mitochondrial cell death priming. Furthermore, we found that Wee1 inhibition altered MCL1 phosphorylation and protein stability, which led to HUWE1-mediated MCL1 degradation. Our findings suggest that Wee1 inhibition can overcome resistance to ABT-199 and provide a rationale for further translational investigation of BCL-2 inhibitor/Wee1 inhibitor combination in breast cancer.