85 results on '"A. Emre Sayan"'
Search Results
2. Mesenchymal–epithelial transition and AXL inhibitor TP-0903 sensitise triple-negative breast cancer cells to the antimalarial compound, artesunate
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Mirko Terragno, Anastassiya Vetrova, Oleg Semenov, A. Emre Sayan, Marina Kriajevska, and Eugene Tulchinsky
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Medicine ,Science - Abstract
Abstract Triple-negative breast cancer (TNBC) is a difficult-to-treat, aggressive cancer type. TNBC is often associated with the cellular program of epithelial-mesenchymal transition (EMT) that confers drug resistance and metastasis. EMT and reverse mesenchymal-epithelial transition (MET) programs are regulated by several signaling pathways which converge on a group of transcription factors, EMT- TFs. Therapy approaches could rely on the EMT reversal to sensitise mesenchymal tumours to compounds effective against epithelial cancers. Here, we show that the antimalarial ROS-generating compound artesunate (ART) exhibits higher cytotoxicity in epithelial than mesenchymal breast cancer cell lines. Ectopic expression of EMT-TF ZEB1 in epithelial or ZEB1 depletion in mesenchymal cells, respectively, reduced or increased ART-generated ROS levels, DNA damage and apoptotic cell death. In epithelial cells, ZEB1 enhanced expression of superoxide dismutase 2 (SOD2) and glutathione peroxidase 8 (GPX8) implicated in ROS scavenging. Although SOD2 or GPX8 levels were unaffected in mesenchymal cells in response to ZEB1 depletion, stable ZEB1 knockdown enhanced total ROS. Receptor tyrosine kinase AXL maintains a mesenchymal phenotype and is overexpressed in TNBC. The clinically-relevant AXL inhibitor TP-0903 induced MET and synergised with ART to generate ROS, DNA damage and apoptosis in TNBC cells. TP-0903 reduced the expression of GPX8 and SOD2. Thus, TP-0903 and ZEB1 knockdown sensitised TNBC cells to ART, likely via different pathways. Synergistic interactions between TP-0903 and ART indicate that combination approaches involving these compounds can have therapeutic prospects for TNBC treatment.
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- 2024
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3. ERCC1 abundance is an indicator of DNA repair-apoptosis decision upon DNA damage
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Sule Erdemir Sayan, Rahul Sreekumar, Rahul Bhome, Alex Mirnezami, Tamer Yagci, and A. Emre Sayan
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Cytology ,QH573-671 - Abstract
Abstract DNA repair is essential for successful propagation of genetic material and fidelity of transcription. Nucleotide excision repair (NER) is one of the earliest DNA repair mechanisms, functionally conserved from bacteria to human. The fact that number of NER genes vary significantly between prokaryotes and metazoans gives the insight that NER proteins have evolved to acquire additional functions to combat challenges associated with a diploid genome, including being involved in the decision between DNA repair and apoptosis. However, no direct association between apoptosis and NER proteins has been shown to date. In this study, we induced apoptosis with a variety of agents, including oxaliplatin, doxorubicin and TRAIL, and observed changes in the abundance and molecular weight of NER complex proteins. Our results showed that XPA, XPC and ERCC1 protein levels change during DNA damage-induced apoptosis. Among these, ERCC1 decrease was observed as a pre-mitochondria depolarisation event which marks the “point of no return” in apoptosis signalling. ERCC1 decrease was due to proteasomal degradation upon lethal doses of oxaliplatin exposure. When ERCC1 protein was stabilised using proteasome inhibitors, the pro-apoptotic activity of oxaliplatin was attenuated. These results explain why clinical trials using proteasome inhibitors and platinum derivatives showed limited efficacy in carcinoma treatment and also the importance of how deep understanding of DNA repair mechanisms can improve cancer therapy.
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- 2024
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4. The ZEB2‐dependent EMT transcriptional programme drives therapy resistance by activating nucleotide excision repair genes ERCC1 and ERCC4 in colorectal cancer
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Rahul Sreekumar, Hajir Al‐Saihati, Muhammad Emaduddin, Karwan Moutasim, Massimiliano Mellone, Ashish Patel, Seval Kilic, Metin Cetin, Sule Erdemir, Marta Salgado Navio, Maria Antonette Lopez, Nathan Curtis, Tamer Yagci, John N. Primrose, Brendan D. Price, Geert Berx, Gareth J. Thomas, Eugene Tulchinsky, Alex Mirnezami, and A. Emre Sayan
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DNA repair ,EMT ,ERCC1 ,oxaliplatin ,ZEB2 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Resistance to adjuvant chemotherapy is a major clinical problem in the treatment of colorectal cancer (CRC). The aim of this study was to elucidate the role of an epithelial to mesenchymal transition (EMT)‐inducing protein, ZEB2, in chemoresistance of CRC, and to uncover the underlying mechanism. We performed IHC for ZEB2 and association analyses with clinical outcomes on primary CRC and matched CRC liver metastases in compliance with observational biomarker study guidelines. ZEB2 expression in primary tumours was an independent prognostic marker of reduced overall survival and disease‐free survival in patients who received adjuvant FOLFOX chemotherapy. ZEB2 expression was retained in 96% of liver metastases. The ZEB2‐dependent EMT transcriptional programme activated nucleotide excision repair (NER) pathway largely via upregulation of the ERCC1 gene and other components in NER pathway, leading to enhanced viability of CRC cells upon oxaliplatin treatment. ERCC1‐overexpressing CRC cells did not respond to oxaliplatin in vivo, as assessed using a murine orthotopic model in a randomised and blinded preclinical study. Our findings show that ZEB2 is a biomarker of tumour response to chemotherapy and risk of recurrence in CRC patients. We propose that the ZEB2‐ERCC1 axis is a key determinant of chemoresistance in CRC.
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- 2021
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5. Epithelial to mesenchymal transition influences fibroblast phenotype in colorectal cancer by altering miR‐200 levels in extracellular vesicles
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Rahul Bhome, Muhammad Emaduddin, Victoria James, Louise M. House, Stephen M. Thirdborough, Massimiliano Mellone, Joeri Tulkens, John N. Primrose, Gareth J. Thomas, Olivier De Wever, Alex H. Mirnezami, and A. Emre Sayan
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cancer‐associated fibroblast ,colorectal cancer ,epithelial to mesenchymal transition ,extracellular vesicle ,MiR‐200 ,stroma ,Cytology ,QH573-671 - Abstract
Abstract Colorectal cancer (CRC) with a mesenchymal gene expression signature has the greatest propensity for distant metastasis and is characterised by the accumulation of cancer‐associated fibroblasts in the stroma. We investigated whether the epithelial to mesenchymal transition status of CRC cells influences fibroblast phenotype, with a focus on the transfer of extracellular vesicles (EVs), as a controlled means of cell–cell communication. Epithelial CRC EVs suppressed TGF‐β‐driven myofibroblast differentiation, whereas mesenchymal CRC EVs did not. This was driven by miR‐200 (miR‐200a/b/c, ‐141), which was enriched in epithelial CRC EVs and transferred to recipient fibroblasts. Ectopic miR‐200 expression or ZEB1 knockdown, in fibroblasts, similarly suppressed myofibroblast differentiation. Supporting these findings, there was a strong negative correlation between miR‐200 and myofibroblastic markers in a cohort of CRC patients in the TCGA dataset. This was replicated in mice, by co‐injecting epithelial or mesenchymal CRC cells with fibroblasts and analysing stromal markers of myofibroblastic phenotype. Fibroblasts from epithelial tumours contained more miR‐200 and expressed less ACTA2 and FN1 than those from mesenchymal tumours. As such, these data provide a new mechanism for the development of fibroblast heterogeneity in CRC, through EV‐mediated transfer of miRNAs, and provide an explanation as to why CRC tumours with greater metastatic potential are CAF rich.
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- 2022
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6. Plexin C1 Marks Liver Cancer Cells with Epithelial Phenotype and Is Overexpressed in Hepatocellular Carcinoma
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Gorkem Odabas, Metin Cetin, Serdar Turhal, Huseyin Baloglu, A. Emre Sayan, and Tamer Yagci
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Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background and Aims. Hepatocellular carcinoma is an aggressive malignancy of the liver and is ranked as the sixth most common cancer worldwide. There is still room for novel markers to improve the diagnosis and monitoring of HCC. Our observations in cancer databases that PLXNC1 is upregulated in HCC led us to investigate the expression profile of Plexin C1 mRNA and protein in HCC cell lines and tissues. Methods. A recombinant protein encompassing part of the extracellular domain of Plexin C1 was used as an antigen for monoclonal antibody development. Transcript and protein levels of Plexin C1 in HCC cell lines were determined by RT-qPCR and Western blotting, respectively. In vivo evaluation of Plexin C1 expression in HCC tissues was accomplished by immunohistochemistry studies in tissue microarrays. Results. A monoclonal antibody, clone PE4, specific to Plexin C1, was generated. In silico and in vitro analyses revealed a Plexin C1-based clustering of well-differentiated HCC cell lines. Staining of HCC and nontumoral liver tissues with PE4 showed a membrane-localized overexpression of Plexin C1 in tumors (p=0.0118). In addition, this expression was correlated with the histological grades of HCC cases. Conclusions. Plexin C1 distinguishes HCC cells of epithelial characteristics from those with the mesenchymal phenotype. Compared to the nontumoral liver, HCC tissues significantly overexpress Plexin C1. The newly generated PE4 antibody can be evaluated in larger HCC cohorts and might be exploited for the examination of Plexin C1 expression pattern in other epithelial malignancies.
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- 2018
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7. Nurullah Genç’in 'Omuzlarımda Dünya' İsimli Hâtırat Eserinde Değerler Eğitimi
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Yunus Emre SAYAN and Mehmet Emin GÜNEL
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Education - Abstract
Sosyal bir varlık olan, yaşadığı toplumun değerlerinden etkilenen, kendisi de bir değer olan insan, ortaya koyduğu edebi eserlerle bu değerlerin yaşanmasını, yayılmasını, sonraki nesillere aktarılmasını sağlar. Bu edebi eserlerden biri olan hatıralar, eğitsel değeri kadar, değer aktarımında da önemli işleve sahiptir. Çalışmada, Türk Dünyasının önemli isimlerinden, yaşadığı toplumun kültürel zenginliklerini, tarihini, güncel gerçeklerini kendine özgü yorumuyla değer merkezli gündeme getiren, kendisi de eğitimci olan Nurullah Genç’in “Omuzlarımda Dünya” isimli hâtırat eseri hem UNESCO evrensel değerleri hem de MEB’in kök değerleri çerçevesinde, değerler eğitimi bakımından ele alınmıştır. İncelenen eserde; 4’ü ortak, 18 değerden hangilerine, ne düzeyde yer verildiği nitel araştırma yöntemiyle incelenmiştir. Doküman incelemesiyle toplanan veriler, betimsel analizle değerlendirilmiştir. İnceleme sonucunda, tespit edilen 13082 değerden, “Sevgi” değeri birinci olurken; onu dostluk, yardımseverlik değerleri izlemektedir. Pinaduz Köyünün, Köy Odasının, irfan mektebi olarak eğitsel rolü de keşfedilmiştir. Araştırmaya konu eserin, ahlaki, milli ve evrensel kök değerlerin öğrencilere kazandırılmasında yararlı olacağı kanısına varılmıştır.
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- 2023
8. ZEB1 and IL-6/11-STAT3 signalling cooperate to define invasive potential of pancreatic cancer cells via differential regulation of the expression of S100 proteins
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Al-Ismaeel, Qais, Neal, Christopher P., Al-Mahmoodi, Hanaa, Almutairi, Zamzam, Al-Shamarti, Ibtihal, Straatman, Kees, Jaunbocus, Nabil, Irvine, Andrew, Issa, Eyad, Moreman, Catherine, Dennison, Ashley R., Emre Sayan, A., McDearmid, Jonathan, Greaves, Peter, Tulchinsky, Eugene, and Kriajevska, Marina
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- 2019
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9. AHİLİKTE DEĞERLER EĞİTİMİ VE BİR DEĞER OLARAK NASİHAT
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YUNUS EMRE SAYAN
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Cultural Studies ,General Arts and Humanities - Abstract
Akhism, highly influential in Islamic and Anatolian societies between 13th and 19th centuries is a professional, commercial, economic, cultural, social, moral and educational organization whose influence in this process exceeds the boundaries of time and space. It consists of highly moral and well-behaved people, each of its members interacting with each other, providing both material and spiritual guidance to its members, and aiming at the perfect human being. On the basis of its acceptance and strong influence for ages the role of its construction with a spirit and understanding inspired by Islamic sources is very great. It is very important scientifically in terms of dealing with Akhism in a way that sheds light on the present, to make sense of it by examining it, evaluate it, and to benefit from the results of a successful experience in the past. Considering that education is an activity of introducing ideal cultural elements to future generations, the introduction of institutions that affect the culture of society in history to today's people is also among the duties of education. In Akhism, educational values, both verbal and behavioral, have been inherited from the past to the present within the framework of the master-assistant master relationship. The aim of this study is to determine the prominent values in Akhism and to reveal the importance of advice value. In this context, the values in the Akhi organization and the value of “advice”, which stands out from these values, were investigated. At the same time, the role of the concept of advice in adding value to individuals and societies has been tried to be determined, although its value has weakened today. The study has been designed with a qualitative research design and the main Islamic sources have been examined in accordance with the document analysis method in the research. Based on the richness of meaning of the concept of advice, the aspect of advice that educates a person, guides, shapes life and makes it valuable and how it builds a lifestyle has been examined. In this study, according to the 5N+ 2K (What, why, where, how, when and who, to whom) technique, the use of advice and teaching methods in the Akhism have been tried to be determined. It is assessed that the results obtained from the richness of meaning of the advice, which has been determined to have an important place in theA khism, will shed light on today's educators and values education. Keywords: Religious Education, Akhism, Values, Advice, Advice in Akhism.
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- 2022
10. Supplementary Data 2 from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
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list of primer sequences, antibody details and primary fibroblasts used
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- 2023
11. Supplementary Data 4 from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
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Significant DDR genesets (from Leading-Edge analysis in GSEA) used to make the DDR_TGFB_signature geneset
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- 2023
12. Macros for image quantification from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
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macros for image quantifications
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- 2023
13. Data from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
- Abstract
Myofibroblastic cancer-associated fibroblast (myoCAF)–rich tumors generally contain few T cells and respond poorly to immune-checkpoint blockade. Although myoCAFs are associated with poor outcome in most solid tumors, the molecular mechanisms regulating myoCAF accumulation remain unclear, limiting the potential for therapeutic intervention. Here, we identify ataxia-telangiectasia mutated (ATM) as a central regulator of the myoCAF phenotype. Differentiating myofibroblasts in vitro and myoCAFs cultured ex vivo display activated ATM signaling, and targeting ATM genetically or pharmacologically could suppress and reverse differentiation. ATM activation was regulated by the reactive oxygen species–producing enzyme NOX4, both through DNA damage and increased oxidative stress. Targeting fibroblast ATM in vivo suppressed myoCAF-rich tumor growth, promoted intratumoral CD8 T-cell infiltration, and potentiated the response to anti–PD-1 blockade and antitumor vaccination. This work identifies a novel pathway regulating myoCAF differentiation and provides a rationale for using ATM inhibitors to overcome CAF-mediated immunotherapy resistance.Significance:ATM signaling supports the differentiation of myoCAFs to suppress T-cell infiltration and antitumor immunity, supporting the potential clinical use of ATM inhibitors in combination with checkpoint inhibition in myoCAF-rich, immune-cold tumors.
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- 2023
14. Supplementary Figures and Legends from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
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supplementary figures and legends
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- 2023
15. Supplementary Data 5 from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
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Non-redundant list of the leading-edge genes and ToppFun pathway analysis from the genesets in Suppl. File 4 used to make the DDR-TGFB_signature geneset
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- 2023
16. Supplementary Data 3 from ATM Regulates Differentiation of Myofibroblastic Cancer-Associated Fibroblasts and Can Be Targeted to Overcome Immunotherapy Resistance
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Gareth J. Thomas, Stephen Durant, Jason L. Parsons, Emre Sayan, Natalia Savelyeva, George D.D. Jones, Vincent Jaquet, Stephen A. Beers, Emma V. King, Viia Valge-Archer, Gareth Hughes, Kerry L. Cox, Josephine F. Buckingham, Christopher J. Hanley, Matthew J. Ellis, Chuan Wang, Sonya James, Maria A. Lopez, Aleksandra Bzura, Lija James, Giulia Venturi, Klaudia Piotrowska, and Massimiliano Mellone
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GSEA between different tumour stromal datasets from GEO and DDR & myoCAF genesets
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- 2023
17. MUÂZ B. CEBEL VE EĞİTİMCİLİĞİ
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Yunus Emre SAYAN
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Social ,Religious Education,Ṣaḥābī,Teaching Method,Spiritual Education-Teaching Strategies ,General Medicine ,Sosyal ,Din Eğitimi,Sahâbî,Muâz b. Cebel,Öğretim Metodu,Manevi Eğitim-Öğretim Stratejileri - Abstract
Ṣaḥābīs, who passed the education of the last envoy of the Rahman, came to the fore with their special efforts in many areas, as well as conveying their Islamic heritage. Benefiting from the experience of the Ṣaḥābīs in the field of religious education can provide different perspectives for Religious Educators of all ages. Muadh b. Cebel has been one of the Ṣaḥābīs that stand out with their successful practices and spiritual guidance, especially in the field of religious education. In this study prepared with the documentation method, despite the short life of Muadh, the fact that he was among the distinguished teachers of the Ṣaḥābīs, the codes of being a successful and good educator, his educationalist characteristics, the methods he applied at the point of Religious Education, pioneering and exemplary practices, strategies were discussed in outline. After the examination, it has been determined that Muadh has carried out important works on Religious Education and has important examples for today's religious educators.Keywords: Religious Education, Ṣaḥābī, Teaching Method, Spiritual Education-Teaching Strategies., Rahmân’ın son elçisinin eğitiminden geçen sahâbîler, İslâm mirasını aktarmaları yanında pek çok alanda ortaya koydukları özel gayretlerle de öne çıkmışlardır. Sahâbîlerin din eğitim-öğretimi alanında ortaya koydukları tecrübeden faydalanmak, çağın her dönemindeki Din Eğitimcileri için farklı açılımlar kazandırabilir. Pek çok ilmi sahada adından söz ettirmesi yanında Muâz b. Cebel, özellikle din eğitim-öğretim alanında başarılı uygulamaları, manevi rehberliği ile öne çıkan sahabilerden biri olmuştur. Dokümantasyon yöntemi ile hazırlanan bu çalışmada Muâz b. Cebel’in, kısa ömrüne rağmen Ashab-ı Suffe’nin seçkin öğretmenleri arasına girmesi, başarılı ve iyi bir eğitimci olmasının kodları, eğitimci özellikleri, Din Eğitimi noktasında uyguladığı metotlar, öncü ve örnek uygulamalar, stratejiler ana hatlarıyla ele alınmıştır. Yapılan inceleme sonrası, Muâz b. Cebel’in, Din Eğitimi konusunda, önemli çalışmalara imza attığı, günümüz din eğitimcilerine önemli örneklikleri olduğu tespit edilmiştir.
- Published
- 2021
18. Social Media Usage Level of the Presidency of Religious Affairs: A Research in the Context of Central and Provincial Organizations
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Yunus Emre SAYAN
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sosyal medya araçları ,social media tools ,BL51-65 ,Religions. Mythology. Rationalism ,Communication. Mass media ,provincial-district mufti ,General Medicine ,din eğitimi ,i̇l-i̇lçe müftülükleri ,BL1-2790 ,P87-96 ,dinî iletişim ,presidency of religious affairs ,religious communication ,diyanet i̇şleri başkanlığı ,religious education ,Philosophy of religion. Psychology of religion. Religion in relation to other subjects - Abstract
Bilgi çağı olarak nitelendirilen yeni dönemde bilgiye ulaşım ve iletişim araçları da zenginleşmiş, dijital araçlar ve sosyal medya öne çıkmıştır. Bu değişimde; bireyler, yeni iletişim araçlarına hızla uyum sağlarken; kurumlar farklılaşmakta, her alanda değişim yaşayan kurumlar yanında, konunun önemini henüz kavrayamayanlar da bulunmaktadır. Bu çalışmanın amacı, ülkemizde özellikle yaygın din eğitim-öğretimi bağlamında önemli bir misyonu olan Diyanet İşleri Başkanlığı’nın yeni medya karşısındaki durumunu, merkez ve taşra teşkilatlarında (81 il müftülüğü), kamuoyuna din hizmeti götürme konusunda görevini ifa ederken, hangi sosyal medya mecralarını kullandığını nicel ve nitel kapsamıyla tespit etmektir. Özellikle 2019 Aralık ayında yaşanan Covid-19 pandemisi sonrası dünya genelindeki dijital dönüşüme paralel, ülkemizde de iletişim kanallarındaki değişimin Diyanet nezdinde nasıl gerçekleştiği ayrıca araştırmanın sorularındandır. Kurumun ve birimlerinin resmî web siteleri incelenerek hangi sosyal medya mecralarını kullandıkları tespit edilmiş, bu mecralarda öne çıkan birimler ve Facebook ve Twitter paylaşımları içerik analizine tabi tutulmuştur. Paylaşımların dini bilgilendirme, haber ve etkinlik ağırlıklı olduğu görülmüştür. Nicel veriler yanında kurumun online ve basılı yayınlarından sosyal medya konuları dokümantasyon yöntemi ile incelenmiştir. İl müftülüklerinin 54’ünün (%67’sinin) en az bir sosyal medya mecrasında yer aldığı 27’sinin henüz bu mecraları kullanmadığı tespit edilmiştir. Çalışmada elde edilen veriler ışığında, merkez teşkilatına yönelik ve yeni başlayacak, henüz başlangıç düzeyinde olan diğer birimlere yönelik sosyal medya stratejileri ışığında önerilerde bulunulmuştur.
- Published
- 2021
19. ATM regulates differentiation of myofibroblastic cancer-associated fibroblasts and can be targeted to overcome immunotherapy resistance
- Author
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Massimiliano Mellone, Klaudia Piotrowska, Giulia Venturi, Lija James, Aleksandra Bzura, Maria A. Lopez, Sonya James, Chuan Wang, Matthew J. Ellis, Christopher J. Hanley, Josephine F. Buckingham, Kerry L. Cox, Gareth Hughes, Viia Valge-Archer, Emma V. King, Stephen A. Beers, Vincent Jaquet, George D.D. Jones, Natalia Savelyeva, Emre Sayan, Jason L. Parsons, Stephen Durant, and Gareth J. Thomas
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Cancer Research ,Oncology - Abstract
Myofibroblastic cancer-associated fibroblast (myoCAF)–rich tumors generally contain few T cells and respond poorly to immune-checkpoint blockade. Although myoCAFs are associated with poor outcome in most solid tumors, the molecular mechanisms regulating myoCAF accumulation remain unclear, limiting the potential for therapeutic intervention. Here, we identify ataxia-telangiectasia mutated (ATM) as a central regulator of the myoCAF phenotype. Differentiating myofibroblasts in vitro and myoCAFs cultured ex vivo display activated ATM signaling, and targeting ATM genetically or pharmacologically could suppress and reverse differentiation. ATM activation was regulated by the reactive oxygen species–producing enzyme NOX4, both through DNA damage and increased oxidative stress. Targeting fibroblast ATM in vivo suppressed myoCAF-rich tumor growth, promoted intratumoral CD8 T-cell infiltration, and potentiated the response to anti–PD-1 blockade and antitumor vaccination. This work identifies a novel pathway regulating myoCAF differentiation and provides a rationale for using ATM inhibitors to overcome CAF-mediated immunotherapy resistance. Significance: ATM signaling supports the differentiation of myoCAFs to suppress T-cell infiltration and antitumor immunity, supporting the potential clinical use of ATM inhibitors in combination with checkpoint inhibition in myoCAF-rich, immune-cold tumors.
- Published
- 2022
20. Son Zamanlarda Gündeme Gelen İnanç Problemleri ve Eğitimcilerin Yaklaşımlarına Yönelik Bir Değerlendirme
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Yunus Emre SAYAN and Mehmet Emin GÜNEL
- Subjects
Philosophy ,Religious studies ,Social Sciences (miscellaneous) - Abstract
Allah’ın varlığını kabul veya ret insanın hayata bakışını tümden etkileyen bir olgudur. Toplumlar huzur ve düzenlerinin devamı için sahip oldukları inancın kendilerinden sonraki nesil tarafından da sürdürülmesini istemektedirler. Allah’a iman eden bir ebeveynin ateist olmuş çocuklarıyla iletişimi ve sağlıklı diyalogu güçtür. Bu noktada son dönemde artışa geçtiği iddia edilen ateizm, deizm gibi tanrının varlığına yönelik inanç sapmaları dini ve kültürel değerlerine bağlı bir toplumun fertlerini kaygılandırmaktadır. Günümüz Türkiye’sinde gündeme gelen Allah’ın varlığına yönelik inanç problemlerini tespit ederek eğitimcilerin bu problemlere yaklaşımını teorik çerçevede ele almayı amaçlayan, dokümantasyon yöntemiyle hazırlanan çalışmada, alanyazındaki araştırmalar taranarak, mevcut durumun fotoğrafını çekip tespit edilen soru ve sorunlara çözüm önerileri ortaya konmaya çalışılmıştır. Son zamanlarda ortaya çıkan inanç problemlerinin birçok sebebi olsa da bunlar arasında ailenin, eğitimcilerin ve öğrenme ortamlarının rolü daha çok öne çıkmaktadır. Bu çalışmada özellikle problemin aile, eğitim ortamları ve eğitimcilerin yöntem ve üsluplarından kaynaklanan yönlerine dikkat çekilmesi amaçlandı. Her bir sorun alanına yönelik tespitler yapılarak bu sorunların çözümüne yönelik öneriler geliştirilmeye çalışılmıştır.
- Published
- 2022
21. Yüksek Din Öğretimi Öğrencilerinin Öğrenme İklimi Algılarının Akademik Özyeterlik ve Akademik Başarıyla İlişkisi Üzerine Bir Araştırma
- Author
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Mustafa Tavukçuoğlu and Yunus Emre Sayan
- Subjects
Philosophy ,Learning climate ,School climate ,Pedagogy ,Religious studies ,Academic achievement ,Psychology ,Social Sciences (miscellaneous) - Abstract
Bilgi çağı olarak nitelendirilen günümüzde, bilginin üretildiği, eğitim-öğretim faaliyetlerinin yapıldığı, öğrenimin gerçekleştiği okullardan, bu çağın gereklerine uygun, özgüveni yüksek bir öğrenci profili yetiştirmesi beklenmektedir. Bu konuda öğrenme iklimi önemlidir. İklim alan yazınında örgüt iklimi ve okul iklimi yerine kullanılan yeni bileşenlerden biri olan, öğrenme yetisini ilgilendiren her türlü faktörü içeren öğrenme iklimi; insan unsurları, öğrenmenin gerçekleştiği sanal ve gerçek mekân özellikleri başta olmak üzere pek çok boyutlarıyla ele alınmakta, öğrenme iklimini ölçmeye yönelik geliştirilen araçlarla ölçümler yapılmaktadır. Elde edilen veriler iyileştirme çalışmalarına kaynaklık etmektedir. Çalışmamızda okul öğrenme iklimi okula bağlılık, öğrenme ortamı, iletişim boyutlarıyla ele alınmıştır. Sosyal Bilişsel Kuramın temel kavramlarından özyeterliğin bir türü olarak, öğrencilerin akademik çalışma gerektiren konularda kendilerine olan öz güvenlerini ifade eden, bu kapsamda öğrenebilmek için bireyin etkili biliş stratejilerini kullanabilme, öğrenme çevrelerini ve öğrenme zamanlarını etkili bir şekilde yönetebilme ve kendi performansını etkili bir şekilde düzenleyebilmesi şeklinde de açıklanabilen akademik özyeterlik, araştırmacılarca farklı boyutlarla ele alınmakta, farklı ölçeklerle ölçümler yapılmaktadır. Çalışmamızda, akademik özyeterlik, bilişsel, sosyal ve teknik boyutlarda ele alınmıştır. İnsanı hayatın akışı içerisinde güçlü kılan asıl unsurlar kendine güven, eleştirel bakış, sosyal ilişkilerde başarı, herhangi bir sportif sanatsal ya da kültürel alana ilgi gibi temel beceriler, öğrencilerin okul ikliminden kazandıklarıyla mümkündür. Bu durumda, okulda iyi bir rüzgâr estirebilmenin, yaşanılası ve sevilesi bir hava oluşturabilmenin, özgün ve eleştirel bir zemine oturabilmenin ancak olumlu ve sürdürülebilir bir okul iklimiyle mümkün olduğunu söyleyebiliriz. Akademik özyeterliği olumlu besleyen okul iklimi, iklimin etkilediği insan unsurlarının başarısını da beraberinde getirecektir. Pozitif okul iklimi güçlü akademik özyeterlik akademik başarının da en büyük araçları haline gelecektir. Öğrenme iklimini ölçmek, okullardaki kişilerarası ilişkiler, rol modeller, beklentileri vb. boyutlarıyla hayatın kalitesini aynı zamanda öğrencilerin başarısını ve memnuniyetini anlamaya yardımcı olabilmektedir. Bu çalışmanın amacı, yüksek din öğrenim gören öğrencilerin öğrenme iklimi algıları ile akademik özyeterlik ve akademik başarıları arasındaki ilişkiyi incelemektir. Bu çerçevede dört temel araştırma sorusu cevaplanmaya çalışılmıştır: (i) Yüksek din öğrenimi öğrencilerinin öğrenme iklimi ve akademik özyeterlik algıları ne düzeydedir? (ii) Yüksek din öğrenimi öğrencilerinin öğrenme iklimi ve akademik özyeterlik algıları arasında anlamlı ilişki var mıdır? (iii) Yüksek din öğrenimi öğrencilerinin yaş, öğrenme iklimi ve akademik özyeterlik inançları akademik başarılarının anlamlı yordayıcısı mıdır? (iv) Yüksek din öğrenimi öğrencilerinin öğrenme iklimine dair olumsuz algılarına ilişkin görüşleri nelerdir? Karma yöntem ve yakınsak paralel araştırma deseni ile desenlenen araştırmada çeşitleme stratejisi kullanılmıştır. Araştırmada, Türkiye'de devlet üniversiteleri bünyesindeki muhtelif İlahiyat ve İslami İlimler Fakültelerinde yüksek din öğrenimi gören, altı fakülteden, nicel bölümde 1147 öğrenciye Owen ve Froman tarafından geliştirilen, Ekici tarafından Türkçe’ye uyarlaması yapılan Akademik Özyeterlik Ölçeği ve Terzi tarafından geliştirilen, Üniversite Öğrencilerine Yönelik Okul İklimi Ölçeği uygulanırken, nitel bölümde ise aynı fakültelerden 18 öğrenciye görüşme formu doldurtulmuştur. 2019 Mayıs ayında gerçekleştirilen araştırma sonrası elde edilen nicel veri setine normallik testi uygulanmış, verilerin analizinde; Bağımsız Gruplar t Testi, Mann Whitney U Testi, Levene testi, Tek Yönlü Varyans Analizi (ANOVA), Scheffe Testi, Kruskal Wallis H Testi, Pearson product-Moment Korelasyonu, Polyserial Korelasyonu ve Yol Analizi yapılmıştır. Nitel veriler betimsel analizle çözümlenmiştir. Araştırma sonuçlarına göre, yüksek din öğrenimi öğrencilerinin öğrenme iklimi algıları olumsuz çıkmıştır. Yüksek din öğrenimi öğrencilerinin genel olarak Akademik Özyeterlik algıları da olumsuz çıkmıştır. Okul İklimi Ölçeğinin genel ortalaması ile Akademik Özyeterlik Algısı Ölçeğinin genel ortalaması arasında korelasyon orta düzeydedir. Araştırma sonucuna göre elde edilen bulgular alanyazın eşliğinde tartışılmış ve yorumlar sonrası yüksek din öğretiminde pozitif bir öğrenme iklimini sağlayacağı, yüksek din öğretimi öğrencilerinin akademik özyeterliklerini güçlendireceği ve akademik başarılarını artıracağı düşünülen çeşitli çözüm önerileri sunulmuştur.
- Published
- 2020
22. EMT-like Activation in CLL Provides Novel Therapeutic Target
- Author
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Charlott Repschlaeger, Mariette Odabashian, Filomena Spada, Zamzam Almutairi, John G. Gribben, Francesco Forconi, Emre Sayan, Alexessander Couto Alves, Charline Giroud, Oleg Fedorov, Marina Kriajevskaia, and Sergey Krysov
- Subjects
Immunology ,Cell Biology ,Hematology ,Biochemistry - Published
- 2022
23. ETS1 is coexpressed with ZEB2 and mediates ZEB2‐induced epithelial‐mesenchymal transition in human tumors
- Author
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Nurettin Tokay, Pelin Balcik-Ercin, Irem Yalim-Camci, Metin Çetin, Tamer Yagci, A. Emre Sayan, and Gorkem Odabas
- Subjects
0301 basic medicine ,Cancer Research ,Epithelial-Mesenchymal Transition ,Biology ,Proto-Oncogene Mas ,Proto-Oncogene Protein c-ets-1 ,03 medical and health sciences ,0302 clinical medicine ,ETS1 ,Cell Movement ,Cell Line, Tumor ,Neoplasms ,Humans ,Epithelial–mesenchymal transition ,Molecular Biology ,Transcription factor ,Zinc Finger E-box Binding Homeobox 2 ,Gene knockdown ,Binding Sites ,Twist-Related Protein 1 ,Nuclear Proteins ,Promoter ,Hep G2 Cells ,Cell biology ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,Matrix Metalloproteinase 9 ,Gene Knockdown Techniques ,030220 oncology & carcinogenesis ,Cancer cell ,Chromatin immunoprecipitation - Abstract
Epithelial-mesenchymal transition (EMT) is an embryonic program that is reactivated in cancer and regulates the invasion and metastasis of tumor cells. Zinc finger E-box binding homeobox 2 (ZEB2) induces EMT by upregulating matrix metalloproteinases (MMP), yet MMP genes lack ZEB2 binding motif in their promoters. Recently, expression of MMPs was associated to the activation of ETS1 transcription factor; however, a link between ZEB2 and ETS proto-oncogene 1, transcription factor (ETS1) remains to be elucidated. Hence, we investigated the transcriptional regulation of ETS1 by ZEB2 after our initial observation that ZEB2 and ETS1 are coexpressed in hepatocellular carcinoma cells (HCCs). Chromatin immunoprecipitation and luciferase reporter assays clearly showed that ZEB2 binds to E-box sequences on the promoter of ETS1. Elevated expression of ETS1 was found in DLD-ZEB2 and A431-ZEB2 inducible systems, and knockdown of ZEB2 caused an explicit downregulation of ETS1 in shZEB2-SNU398 and shZEB2-SK-HEP-1 cells. Repression of ETS1 expression in ZEB2-induced conditions substantially impaired the migration and invasive capacities of DLD1 cells. Mechanistically, knockdown of ETS1 in ZEB2-expressing cells resulted in the downregulation of established ZEB2 targets TWIST and MMP9. Correlation analyses in HCC lines, cancer complementary DNA arrays, and The Cancer Genome Atlas RNA-sequencing data set revealed that ZEB2 and ETS1 are coexpressed, and their expressions in human tumors show a highly significant positive correlation. Our results demonstrated that ZEB2 acts as an upstream regulator of ETS1 and, in turn, ETS1 maintains ZEB2-induced EMT. These findings add another level of complexity to the understanding of ZEB2 in the invasion and metastasis of cancer cells, and put ZEB2/ETS1 axis as a novel therapeutic target in human malignancies.
- Published
- 2019
24. The synthesis of biologically active indolocarbazole natural products
- Author
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A. Emre Sayan, George E Chambers, and Richard C. D. Brown
- Subjects
Biological Products ,Indoles ,010405 organic chemistry ,Drug discovery ,Carbazole ,Organic Chemistry ,Carbazoles ,Biological activity ,010402 general chemistry ,Indolocarbazole ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,0104 chemical sciences ,chemistry.chemical_compound ,Structure-Activity Relationship ,chemistry ,Drug Discovery ,Chemical methodology ,Humans - Abstract
Covering: up to 2020 The indolocarbazoles, in particular indolo[2,3-a]pyrrolo[3,4-c]carbazole derivatives, are an important class of natural products that exhibit a wide range of biological activities. There has been a plethora of synthetic approaches to this family of natural products, leading to advances in chemical methodology, as well as affording access to molecular scaffolds central to protein kinase drug discovery programmes. In this review, we compile and summarise the synthetic approaches to the indolo[2,3-a]pyrrolo[3,4-c]carbazole derivatives, spanning the period from their isolation in 1980 up to 2020. The selected natural products include indolocarbazoles not functionalised at indolic nitrogen, pyranosylated indolocarbazoles, furanosylated indolocarbazoles and disaccharideindolocarbazoles.
- Published
- 2021
25. The ZEB2-dependent EMT transcriptional programme drives therapy resistance by activating nucleotide excision repair genes ERCC1 and ERCC4 in colorectal cancer
- Author
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Eugene Tulchinsky, Tamer Yagci, Seval Kilic, Maria Antonette Lopez, Rahul Sreekumar, Brendan D. Price, Metin Çetin, Muhammad Emaduddin, Ashish Patel, Sule Erdemir, Karwan A. Moutasim, Hajir Al-Saihati, Marta Salgado Navio, A. Emre Sayan, John N. Primrose, Geert Berx, Nathan Curtis, Gareth J. Thomas, Massimiliano Mellone, and Alex H. Mirnezami
- Subjects
0301 basic medicine ,Cancer Research ,DNA Repair ,Organoplatinum Compounds ,Transcription, Genetic ,Colorectal cancer ,TO-MESENCHYMAL TRANSITION ,Leucovorin ,Mice ,0302 clinical medicine ,FOLFOX ,Antineoplastic Combined Chemotherapy Protocols ,Medicine and Health Sciences ,ZEB1 ,RC254-282 ,Research Articles ,ZEB2 ,CHEMORESISTANCE ,MOLECULAR-MECHANISMS ,Liver Neoplasms ,EMT ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,General Medicine ,CHEMOTHERAPY ,DNA-Binding Proteins ,Oncology ,030220 oncology & carcinogenesis ,DNA-REPAIR ,Molecular Medicine ,Biomarker (medicine) ,Fluorouracil ,Colorectal Neoplasms ,medicine.drug ,Research Article ,EXPRESSION ,Epithelial-Mesenchymal Transition ,PROTEINS ,DNA repair ,03 medical and health sciences ,Cell Line, Tumor ,Genetics ,medicine ,Animals ,Humans ,Epithelial–mesenchymal transition ,neoplasms ,Zinc Finger E-box Binding Homeobox 2 ,business.industry ,oxaliplatin ,Biology and Life Sciences ,BLADDER ,medicine.disease ,Endonucleases ,Xenograft Model Antitumor Assays ,digestive system diseases ,Oxaliplatin ,030104 developmental biology ,Drug Resistance, Neoplasm ,CELLS ,Cancer research ,ERCC1 ,business ,ERCC4 ,Nucleotide excision repair - Abstract
Resistance to adjuvant chemotherapy is a major clinical problem in the treatment of colorectal cancer (CRC). The aim of this study was to elucidate the role of an epithelial to mesenchymal transition (EMT)‐inducing protein, ZEB2, in chemoresistance of CRC, and to uncover the underlying mechanism. We performed IHC for ZEB2 and association analyses with clinical outcomes on primary CRC and matched CRC liver metastases in compliance with observational biomarker study guidelines. ZEB2 expression in primary tumours was an independent prognostic marker of reduced overall survival and disease‐free survival in patients who received adjuvant FOLFOX chemotherapy. ZEB2 expression was retained in 96% of liver metastases. The ZEB2‐dependent EMT transcriptional programme activated nucleotide excision repair (NER) pathway largely via upregulation of the ERCC1 gene and other components in NER pathway, leading to enhanced viability of CRC cells upon oxaliplatin treatment. ERCC1‐overexpressing CRC cells did not respond to oxaliplatin in vivo, as assessed using a murine orthotopic model in a randomised and blinded preclinical study. Our findings show that ZEB2 is a biomarker of tumour response to chemotherapy and risk of recurrence in CRC patients. We propose that the ZEB2‐ERCC1 axis is a key determinant of chemoresistance in CRC., Here, we show that the expression of ZEB2 marks reduced overall and disease‐free survival in primary and secondary colorectal cancers (CRCs). ZEB2 overexpression promoted chemoresistance to oxaliplatin in vitro and in vivo by transcriptionally activating nucleotide excision repair genes ERCC1 and ERCC4. Overall ZEB2 is a promising biomarker predicting both therapy response and metastatic ability of CRCs.
- Published
- 2021
26. Social Media Usage On Behalf Of Higher Religıous Education Institutions In Turkey And The Investigation Of Social Media Strategy Of Faculties
- Author
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Yunus Emre Sayan
- Subjects
Social ,Din Eğitimi,Yüksek Din Öğretimi,İslami İlimler Fakültesi,İlahiyat,Sosyal Medya,sosyal medya stratejileri ,General Medicine ,Religious Education,Higher Religıous Education,Faculty of Islamic Sciences,Theology,Social Media,Social Media Strategy ,Sosyal - Abstract
Günlük hayata etkileriyle sosyal medya, kişiler arası iletişimin yanında kurumların da iletişimini etkilemiştir. Çok amaçlı iletişim stratejileri bağlamında, sosyal medya araçlarını da kullanmak zorunda kalan kurumlarda, adaptasyonun değişik hızda/anlayışlarda seyrettiği, günlük faaliyetlerini sosyal medyayla yürüten kurumların yanında bu durumun hâlâ gündeme gelmediği gözlenmiştir. Mevcut/potansiyel insan unsurlarıyla ve diğer kurumlarla çok yönlü etkileşimde, eğitim kurumları da bu mecralarda yerlerini almıştır. Çalışmada, Yüksek Din Öğretimi Kurumları’nın sosyal medyada hangi mecralarda, ne düzeyde yer aldıkları incelenmiştir. Kurumların web siteleri 10 Temmuz 2020’de incelenerek, sosyal medya mecraları ve varoldukları mecralardaki toplam takipçi sayısı tespit edilmiş ve mevcut 97 Yüksek Din Öğretimi Kurumu’ndan, Facebook, Instagram, Twitter ve YouTube’da aktif kullanımıyla ve en çok takipçi sayısıyla öne çıkanların sosyal medya stratejileri örnek olay olarak sunulmuş, tecrübeleri, hesapları yöneten uzman kişilerle görüşülerek derinlemesine ele alınmış ve anlaşılmaya çalışılmıştır. Betimsel tarama yöntemiyle nicel veriler, görüşme formu ile nitel veriler elde edilmiştir. Araştırma sonucu elde edilen bulgular bağlamında, İlahiyat/İslami İlimler Fakültelerinin muhtemel sosyal medya politikalarına yönelik stratejilere, geliştirici önerilere yer verilmiştir., Social media, with its effects on daily life, has affected the communication of institutions as well as interpersonal communication, and in institutions that have to use social media tools in the context of multi-purpose communication strategies, it is observed that the issue is still not on the agenda in some of them, besides conducting their daily activities with social media, where adaptation follows at different speeds / understandings. Educational institutions have also taken their place in these channels in multi-faceted interaction with existing / potential human elements and other institutions. In study, in which channels and at what level Higher Religious Education Institutions are involved in social media was examined. The websites of the institutions were examined on July 10, 2020, and the total number of followers in the social media channels and the channels they exist was determined and the social media strategies of the existing 97 Higher Religious Education Institutions, which stand out with their active use on Facebook, Instagram, Twitter and YouTube and with the highest number of followers, were presented as a case study, their experiences have been discussed in depth with the experts managing the accounts and they have been understood. Quantitative data were obtained by the descriptive screening method, and qualitative data were obtained by interview form. In the context of the findings obtained as a result of the research, strategies and developing suggestions for possible social media policies of the Faculty of Theology / Islamic Sciences are included.
- Published
- 2020
27. Activity of IL-12/15/18 primed natural killer cells against hepatocellular carcinoma
- Author
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Salim I. Khakoo, Rebecca Fulton, A. Emre Sayan, Pauline Rettman, Jonathan Coad, Lihui Zhuang, and Aymen Al-Shamkhani
- Subjects
Male ,Carcinoma, Hepatocellular ,medicine.medical_treatment ,Cell ,Mice, Transgenic ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Cytotoxic T cell ,Cancer ,Aged ,Innate immunity ,Interleukin-15 ,Innate immune system ,Hepatology ,business.industry ,Liver Neoplasms ,Interleukin-18 ,Immunotherapy ,NKG2D ,medicine.disease ,Interleukin-12 ,Immunity, Innate ,digestive system diseases ,3. Good health ,Killer Cells, Natural ,Disease Models, Animal ,medicine.anatomical_structure ,Liver ,NK Cell Lectin-Like Receptor Subfamily K ,Cell culture ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Interleukin 12 ,Cancer research ,Cytokines ,Original Article ,Female ,030211 gastroenterology & hepatology ,business - Abstract
Background Hepatocellular carcinoma (HCC) is common, but remains difficult to treat. Natural killer (NK) cells are cells of the innate immune system that have potent anti-cancer activity. Recent work has shown that stimulation with IL-12/15/18 leads to the generation of NK cells with enhanced functional and putative “memory” properties. We have investigated the activity of these NK cells against HCC cell lines in vitro and in a mouse model. Methods NK cells from healthy donors or individuals with HCC were activated with IL-12/15/18 in vitro and tested for cytotoxic activity against a panel of human HCC cell lines. IL-12/15/18 primed murine NK cells were then infused into a murine model of spontaneously arising HCC to test for anti-tumor activity. Results NK cells from patients and healthy controls had similar expression levels of activating and inhibitory NK cell receptors. However, proliferation of NK cells from HCC patients was weaker than healthy controls in response to IL-12/15/18 and IL-2 (p
- Published
- 2018
28. AXL Receptor in Cancer Metastasis and Drug Resistance: When Normal Functions Go Askew
- Author
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Almira Auyez, A. Emre Sayan, Marina Kriajevska, and Eugene Tulchinsky
- Subjects
Cancer Research ,drug resistance ,Stromal cell ,Innate immune system ,biology ,GAS6 ,AXL ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Cancer ,Review ,TAM receptors ,medicine.disease ,Receptor tyrosine kinase ,Metastasis ,epithelial-mesenchymal plasticity ,Immune system ,Oncology ,Cancer cell ,biology.protein ,medicine ,Cancer research ,metastasis ,RC254-282 - Abstract
Simple Summary AXL is a member of the TAM (TYRO3, AXL, MER) family of receptor tyrosine kinases. In normal physiological conditions, AXL is involved in removing dead cells and their remains, and limiting the duration of immune responses. Both functions are utilized by cancers in the course of tumour progression. Cancer cells use the AXL pathway to detect toxic environments and to activate molecular mechanisms, thereby ensuring their survival or escape from the toxic zone. AXL is instrumental in controlling genetic programs of epithelial-mesenchymal and mesenchymal-epithelial transitions, enabling cancer cells to metastasize. Additionally, AXL signaling suppresses immune responses in tumour microenvironment and thereby helps cancer cells to evade immune surveillance. The broad role of AXL in tumour biology is the reason why its inhibition sensitizes tumours to a broad spectrum of anti-cancer drugs. In this review, we outline molecular mechanisms underlying AXL function in normal tissues, and discuss how these mechanisms are adopted by cancers to become metastatic and drug-resistant. Abstract The TAM proteins TYRO3, AXL, and MER are receptor tyrosine kinases implicated in the clearance of apoptotic debris and negative regulation of innate immune responses. AXL contributes to immunosuppression by terminating the Toll-like receptor signaling in dendritic cells, and suppressing natural killer cell activity. In recent years, AXL has been intensively studied in the context of cancer. Both molecules, the receptor, and its ligand GAS6, are commonly expressed in cancer cells, as well as stromal and infiltrating immune cells. In cancer cells, the activation of AXL signaling stimulates cell survival and increases migratory and invasive potential. In cells of the tumour microenvironment, AXL pathway potentiates immune evasion. AXL has been broadly implicated in the epithelial-mesenchymal plasticity of cancer cells, a key factor in drug resistance and metastasis. Several antibody-based and small molecule AXL inhibitors have been developed and used in preclinical studies. AXL inhibition in various mouse cancer models reduced metastatic spread and improved the survival of the animals. AXL inhibitors are currently being tested in several clinical trials as monotherapy or in combination with other drugs. Here, we give a brief overview of AXL structure and regulation and discuss the normal physiological functions of TAM receptors, focusing on AXL. We present a theory of how epithelial cancers exploit AXL signaling to resist cytotoxic insults, in order to disseminate and relapse.
- Published
- 2021
29. A minimum core outcome dataset for the reporting of preclinical chemotherapeutic drug studies: Lessons learned from multiple discordant methodologies in the setting of colorectal cancer
- Author
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Malcolm A. West, Alex H. Mirnezami, Timothy J. Underwood, Emre Sayan, A. Roman, Stephen R. Wedge, and John N. Primrose
- Subjects
0301 basic medicine ,Oncology ,medicine.medical_specialty ,Pathology ,Colorectal cancer ,Drug Evaluation, Preclinical ,Antineoplastic Agents ,Outcome (game theory) ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Humans ,Adverse effect ,business.industry ,Cancer ,Hematology ,medicine.disease ,Disease Models, Animal ,Regimen ,030104 developmental biology ,030220 oncology & carcinogenesis ,Chemotherapeutic drugs ,Colorectal Neoplasms ,business - Abstract
In vivo studies in animal models are critical tools necessary to study the fundamental complexity of carcinogenesis. A constant strive to improve animal models in cancer exists, especially those investigating the use of chemotherapeutic effectiveness. In the present systematic review, colorectal cancer (CRC) is used as an example to highlight and critically evaluate the range of reporting strategies used when investigating chemotherapeutic agents in the preclinical setting. A systematic review examining the methodology and reporting of preclinical chemotherapeutic drug studies using CRC murine models was conducted. A total of 45 studies were included in this systematic review. The literature was found to be highly heterogeneous with various cell lines, animal strains, animal ages and chemotherapeutic compounds/regimens tested, proving difficult to compare outcomes between similar studies or indeed gain any significant insight into which chemotherapeutic regimen caused adverse events. From this analysis we propose a minimum core outcome dataset that could be regarded as a standardised way of reporting results from in vivo experimentation.
- Published
- 2017
30. ROR1 Expression and Its Functional Significance in Hepatocellular Carcinoma Cells
- Author
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Patrick J. Duriez, Metin Çetin, Abdulkadir Emre Sayan, Tamer Yagci, Gorkem Odabas, Pelin Balcik-Ercin, Leon Douglas, and Irem Yalim-Camci
- Subjects
Carcinoma, Hepatocellular ,Epithelial-Mesenchymal Transition ,medicine.drug_class ,Cell ,Antineoplastic Agents ,Apoptosis ,Monoclonal antibody ,Receptor Tyrosine Kinase-like Orphan Receptors ,Receptor tyrosine kinase ,Article ,Mice ,Cell Movement ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Anoikis ,HCC ,lcsh:QH301-705.5 ,neoplasms ,ROR1 ,Cell Proliferation ,drug resistance ,biology ,Liver Neoplasms ,G1 Phase ,EMT ,Antibodies, Monoclonal ,General Medicine ,Cell cycle ,medicine.disease ,digestive system diseases ,Up-Regulation ,drug efflux ,Gene Expression Regulation, Neoplastic ,medicine.anatomical_structure ,Phenotype ,lcsh:Biology (General) ,Drug Resistance, Neoplasm ,monoclonal antibody ,Hepatocellular carcinoma ,biology.protein ,Cancer research ,Antibody ,hallmarks of cancer - Abstract
Background: Hepatocellular carcinoma (HCC) is a common and deadly cancer, however, very little improvement has been made towards its diagnosis and prognosis. The expression and functional contribution of the receptor tyrosine kinase ROR1 have not been investigated in HCC before. Hence, we investigated the expression of ROR1 in HCC cells and assessed its involvement in hepatocarcinogenesis. Methods: Recombinant bacterial ROR1 protein was used as an immunogen to generate ROR1 monoclonal antibodies. ROR1 transcript levels were detected by RT-qPCR and the protein expression of ROR1 in HCC was assessed by Western blotting by using homemade anti-ROR1 monoclonal antibodies. Apoptosis, cell cycle, trans-well migration, and drug efflux assays were performed in shRNA-ROR1 HCC cell clones to uncover the functional contribution of ROR1 to hepatocarcinogenesis. Results: New ROR1 antibodies specifically detected endogenous ROR1 protein in human and mouse HCC cell lines. ROR1-knockdown resulted in decreased proliferation and migration but enhanced resistance to apoptosis and anoikis. The observed chemotherapy-resistant phenotype of ROR1-knockdown cells was due to enhanced drug efflux and increased expression of multi-drug resistance genes. Conclusions: ROR1 is expressed in HCC and contributes to disease development by interfering with multiple pathways. Acquired ROR1 expression may have diagnostic and prognostic value in HCC.
- Published
- 2019
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31. A combination of trastuzumab and BAG-1 inhibition synergistically targets HER2 positive breast cancer cells
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Alison Yeomans, Stephen A. Beers, Margaret Ashton-Key, Ramsey I. Cutress, Emmanouil Papadakis, Stéphanie A Laversin, A. Emre Sayan, Graham Packham, Hermann Stuppner, Natalia Robson, Sarah G. Bailey, Stefan Schwaiger, and Jakob Troppmair
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0301 basic medicine ,MAPK/ERK pathway ,Receptor, ErbB-2 ,Clone (cell biology) ,Breast Neoplasms ,Mice, SCID ,Pharmacology ,Transfection ,BAG-1 ,resistance ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,breast cancer ,0302 clinical medicine ,Breast cancer ,Mice, Inbred NOD ,Trastuzumab ,HER2 ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Animals ,Humans ,Benzothiazoles ,RNA, Small Interfering ,skin and connective tissue diseases ,neoplasms ,Protein kinase B ,Cell Proliferation ,Aniline Compounds ,business.industry ,Drug Synergism ,medicine.disease ,Combined Modality Therapy ,Xenograft Model Antitumor Assays ,DNA-Binding Proteins ,030104 developmental biology ,Oncology ,chemistry ,SKBR3 ,Cell culture ,030220 oncology & carcinogenesis ,Female ,Growth inhibition ,business ,Research Paper ,Transcription Factors ,medicine.drug - Abstract
Treatment of HER2+ breast cancer with trastuzumab is effective and combination anti-HER2 therapies have demonstrated benefit over monotherapy in the neoadjuvant and metastatic settings. This study investigated the therapeutic potential of targeting the BAG-1 protein co-chaperone in trastuzumab-responsive or -resistant cells. In the METABRIC dataset, BAG-1 mRNA was significantly elevated in HER2+ breast tumors and predicted overall survival in a multivariate analysis (HR = 0.81; p = 0.022). In a breast cell line panel, BAG-1 protein was increased in HER2+ cells and was required for optimal growth as shown by siRNA knockdown. Overexpression of BAG-1S in HER2+ SKBR3 cells blocked growth inhibition by trastuzumab, whereas overexpression of a mutant BAG-1S protein (BAG-1S H3AB), defective in binding HSC70, potentiated the effect of trastuzumab. Injection of a Tet-On SKBR3 clone, induced to overexpress myc-BAG-1S into the mammary fat pads of immunocompromised mice, resulted in 2-fold larger tumors compared to uninduced controls. Induction of myc-BAG-1S expression in two Tet-On SKBR3 clones attenuated growth inhibition by trastuzumab in vitro. Targeting endogenous BAG-1 by siRNA enhanced growth inhibition of SKBR3 and BT474 cells by trastuzumab, while BAG-1 protein-protein interaction inhibitor (Thio-S or Thio-2) plus trastuzumab combination treatment synergistically attenuated growth. In BT474 cells this reduced protein synthesis, caused G1/S cell cycle arrest and targeted the ERK and AKT signaling pathways. In a SKBR3 subpopulation with acquired resistance to trastuzumab BAG-1 targeting remained effective and either Thio-2 or BAG-1 siRNA reduced growth more compared to trastuzumab-responsive parental cells. In summary, targeting BAG-1 function in combination with anti-HER2 therapy might prove beneficial.
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- 2016
32. ZEB1 and IL-6/11-STAT3 signalling cooperate to define invasive potential of pancreatic cancer cells via differential regulation of the expression of S100 proteins
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A. Emre Sayan, Eyad Issa, Hanaa Al-Mahmoodi, Andrew F. Irvine, Jonathan R. McDearmid, Ibtihal Al-Shamarti, Nabil Jaunbocus, Peter Greaves, Ashley R. Dennison, Zamzam Almutairi, Christopher P. Neal, K.R. Straatman, Qais Al-Ismaeel, Marina Kriajevska, Eugene Tulchinsky, and Catherine Moreman
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STAT3 Transcription Factor ,Cancer Research ,Epithelial-Mesenchymal Transition ,Inflammation ,Article ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Pancreatic cancer ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Neoplasm Invasiveness ,Epithelial–mesenchymal transition ,STAT3 ,Zebrafish ,Regulation of gene expression ,biology ,Interleukin-6 ,S100 Proteins ,Zinc Finger E-box-Binding Homeobox 1 ,medicine.disease ,biology.organism_classification ,Interleukin-11 ,Cell invasion ,Gene Expression Regulation, Neoplastic ,Pancreatic Neoplasms ,Oncology ,Cell culture ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,medicine.symptom ,Signal Transduction - Abstract
Background S100 proteins have been implicated in various aspects of cancer, including epithelial-mesenchymal transitions (EMT), invasion and metastasis, and also in inflammatory disorders. Here we examined the impact of individual members of this family on the invasion of pancreatic ductal adenocarcinoma (PDAC) cells, and their regulation by EMT and inflammation. Methods Invasion of PDAC cells was analysed in zebrafish embryo xenografts and in transwell invasion assays. Expression and regulation of S100 proteins was studied in vitro by immunoblotting, quantitative PCR and immunofluorescence, and in pancreatic lesions by immunohistochemistry. Results Whereas the expression of most S100 proteins is characteristic for epithelial PDAC cell lines, S100A4 and S100A6 are strongly expressed in mesenchymal cells and upregulated by ZEB1. S100A4/A6 and epithelial protein S100A14 respectively promote and represses cell invasion. IL-6/11-STAT3 pathway stimulates expression of most S100 proteins. ZEB1 synergises with IL-6/11-STAT3 to upregulate S100A4/A6, but nullifies the effect of inflammation on S100A14 expression. Conclusion EMT/ZEB1 and IL-6/11-STAT3 signalling act independently and congregate to establish the expression pattern of S100 proteins, which drives invasion. Although ZEB1 regulates expression of S100 family members, these effects are masked by IL-6/11-STAT3 signalling, and S100 proteins cannot be considered as bona fide EMT markers in PDAC.
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- 2018
33. The Colorectal Cancer Microenvironment: Strategies for Studying the Role of Cancer-Associated Fibroblasts
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A. Emre Sayan, Massimiliano Mellone, Rahul Bhome, Katherine Emo, Alex H. Mirnezami, and Gareth J. Thomas
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0301 basic medicine ,Colorectal cancer ,Primary Cell Culture ,Mice, Nude ,Laser Capture Microdissection ,Mice, SCID ,Extracellular vesicles ,Article ,Metastasis ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Cancer-Associated Fibroblasts ,Tumor Cells, Cultured ,Tumor Microenvironment ,Medicine ,Animals ,Humans ,neoplasms ,Tumor microenvironment ,business.industry ,Cancer ,medicine.disease ,Xenograft Model Antitumor Assays ,digestive system diseases ,Coculture Techniques ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer research ,Disease Progression ,Stromal Cells ,business ,Colorectal Neoplasms - Abstract
Colorectal cancer (CRC) is a key public health concern and the second highest cause of cancer related death in Western society. A dynamic interaction exists between CRC cells and the surrounding tumor microenvironment, which can stimulate not only the development of CRC, but its progression and metastasis, as well as the development of resistance to therapy. In this chapter, we focus on the role of fibroblasts within the CRC tumor microenvironment and describe some of the key methods for their study, as well as the evaluation of dynamic interactions within this biological ecosystem.
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- 2018
34. Plexin C1 marks liver cancer cells with epithelial phenotype and is overexpressed in hepatocellular carcinoma
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A. Emre Sayan, Metin Çetin, Serdar Turhal, Tamer Yagci, Gorkem Odabas, and Huseyin Baloglu
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Male ,0301 basic medicine ,Carcinoma, Hepatocellular ,animal structures ,Article Subject ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Carcinoma ,Humans ,RNA, Messenger ,lcsh:RC799-869 ,neoplasms ,Tissue microarray ,Hepatology ,biology ,business.industry ,Cell Membrane ,Liver Neoplasms ,Plexin ,Gastroenterology ,Antibodies, Monoclonal ,Cancer ,Epithelial Cells ,General Medicine ,Middle Aged ,medicine.disease ,digestive system diseases ,Up-Regulation ,Phenotype ,030104 developmental biology ,Liver ,Tissue Array Analysis ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Monoclonal ,embryonic structures ,Cancer research ,biology.protein ,Receptors, Virus ,Immunohistochemistry ,Female ,lcsh:Diseases of the digestive system. Gastroenterology ,Neoplasm Grading ,Liver cancer ,business ,Research Article - Abstract
Background and Aims. Hepatocellular carcinoma is an aggressive malignancy of the liver and is ranked as the sixth most common cancer worldwide. There is still room for novel markers to improve the diagnosis and monitoring of HCC. Our observations in cancer databases that PLXNC1 is upregulated in HCC led us to investigate the expression profile of Plexin C1 mRNA and protein in HCC cell lines and tissues. Methods. A recombinant protein encompassing part of the extracellular domain of Plexin C1 was used as an antigen for monoclonal antibody development. Transcript and protein levels of Plexin C1 in HCC cell lines were determined by RT-qPCR and Western blotting, respectively. In vivo evaluation of Plexin C1 expression in HCC tissues was accomplished by immunohistochemistry studies in tissue microarrays. Results. A monoclonal antibody, clone PE4, specific to Plexin C1, was generated. In silico and in vitro analyses revealed a Plexin C1-based clustering of well-differentiated HCC cell lines. Staining of HCC and nontumoral liver tissues with PE4 showed a membrane-localized overexpression of Plexin C1 in tumors (p=0.0118). In addition, this expression was correlated with the histological grades of HCC cases. Conclusions. Plexin C1 distinguishes HCC cells of epithelial characteristics from those with the mesenchymal phenotype. Compared to the nontumoral liver, HCC tissues significantly overexpress Plexin C1. The newly generated PE4 antibody can be evaluated in larger HCC cohorts and might be exploited for the examination of Plexin C1 expression pattern in other epithelial malignancies.
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- 2018
35. Clinical Relevance, Prognostic Potential, and Therapeutic Strategies of Noncoding RNAs in Cancer
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Rahul Bhome, Louise M. House, Katherine Emo, Alex H. Mirnezami, and Emre Sayan
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Clinical trial ,microRNA ,medicine ,Piwi-interacting RNA ,Cancer ,Identification (biology) ,Biology ,Bioinformatics ,Non-coding RNA ,medicine.disease ,Genome ,Long non-coding RNA - Abstract
Noncoding RNAs (ncRNAs) are master regulators of the genome, controlling the most fundamental of cellular processes. Several hundred studies have demonstrated their dysregulation across a range of cancer types, and translational follow-on studies have led to the development of putative ncRNA biomarkers for identification and staging of cancer. Additionally, mechanistic studies have clearly identified key functions for ncRNAs in cancer progression, and highlighted actionable pathways to be targeted by ncRNA-directed therapies. Consequently, ncRNA-derived therapeutics is now entering later stage clinical trials. In this chapter, we describe the classification of ncRNAs, their biology, and their potential clinical applications.
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- 2018
36. List of Contributors
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Santanu Adhikary, Carlos Baliñas, Shakri Banerjee, Sharmila A. Bapat, Rahul Bhome, Liberalis D. Boila, Vincenzo Bonnici, Debojit Bose, Laura Boyero, Jayprokas Chakrabarti, Damayanti Chakravarti, JiaJia Chan, Alain Chariot, Shankha S. Chatterjee, Taiping Chen, Pierre Close, Isabel F. Coira, Marta Cuadros, Juan Cui, Chandrima Das, Shaoli Das, Simone de Brot, Ng Desi, Nadya Dimitrova, Rachel L. Dittmar, Katherine Emo, Sayak Ganguli, Kshipra M. Gharpure, Suman Ghosal, Rosalba Giugno, Damjan Glavacˇ, Frank Grützner, Sohini Gupta, Agnik Halder, Nina Hauptman, Antonio Herrera, Louise House, Changzhi Huang, Shenglin Huang, Reuben Jacob, Victoria James, Daša Jevšinek Skok, Ragini Kondetimmanahalli, Eunice Lee, Sebastian A. Leidel, Yan Li, Yuan Li, Gabriel Lopez-Berestein, Jose A. Lupiáñez, Joel Martín-Padrón, Pedro P. Medina, Alex Mirnezami, Sanga Mitra, Nigel P. Mongan, Shravanti Mukherjee, Suchismita Panda, Paola Peinado, Alfredo Pulvirenti, Fernando J. Reyes-Zurita, Maria I. Rodriguez, Susanta Roychoudhury, Siddhartha Roy, Eva E. Rufino-Palomares, Catrin S. Rutland, Emre Sayan, Flavia Scoyni, Amitava Sengupta, Sharmila Sengupta, Subrata Sen, Sweta Sharma Saha, Anjali Shiras, Yuming Shi, Sayantani Sinha, Ondrej Slaby, Anil K. Sood, Kamila Souckova, Yvonne Tay, Yu Wang, Zhiguo Wang, Sherry Y. Wu, Tianqi Yang, Eda Yildirim, and Zhengzhou Ying
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- 2018
37. Genome-Wide Analysis Of Endogenously Expressed Zeb2 Binding Sites Reveals Inverse Correlations Between Zeb2 And Galnac-Transferase Galnt3 In Human Tumors
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Irem Yalim-Camci, Tamer Yagci, Pelin Balcik-Ercin, Nurettin Tokay, A. Emre Sayan, Metin Çetin, and Gorkem Odabas
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0301 basic medicine ,Cancer Research ,Epithelial-Mesenchymal Transition ,Blotting, Western ,Human Protein Atlas ,Biology ,03 medical and health sciences ,Cell Line, Tumor ,medicine ,Humans ,Gene ,Zinc Finger E-box Binding Homeobox 2 ,Regulation of gene expression ,Binding Sites ,General Medicine ,medicine.disease ,Molecular biology ,Primary tumor ,Chromatin ,ChIP-sequencing ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,Oncology ,Regulatory sequence ,N-Acetylgalactosaminyltransferases ,Molecular Medicine ,Human genome ,Genome-Wide Association Study - Abstract
ZEB2 is a transcriptional repressor that regulates epithelial-to-mesenchymal transition (EMT) through binding to bipartite E-box motifs in gene regulatory regions. Despite the abundant presence of E-boxes within the human genome and the multiplicity of pathophysiological processes regulated during ZEB2-induced EMT, only a small fraction of ZEB2 targets has been identified so far. Hence, we explored genome-wide ZEB2 binding by chromatin immunoprecipitation-sequencing (ChIP-seq) under endogenous ZEB2 expression conditions. For ChIP-Seq we used an anti-ZEB2 monoclonal antibody, clone 6E5, in SNU398 hepatocellular carcinoma cells exhibiting a high endogenous ZEB2 expression. The ChIP-Seq targets were validated using ChIP-qPCR, whereas ZEB2-dependent expression of target genes was assessed by RT-qPCR and Western blotting in shRNA-mediated ZEB2 silenced SNU398 cells and doxycycline-induced ZEB2 overexpressing colorectal carcinoma DLD1 cells. Changes in target gene expression were also assessed using primary human tumor cDNA arrays in conjunction with RT-qPCR. Additional differential expression and correlation analyses were performed using expO and Human Protein Atlas datasets. Over 500 ChIP-Seq positive genes were annotated, and intervals related to these genes were found to include the ZEB2 binding motif CACCTG according to TOMTOM motif analysis in the MEME Suite database. Assessment of ZEB2-dependent expression of target genes in ZEB2-silenced SNU398 cells and ZEB2-induced DLD1 cells revealed that the GALNT3 gene serves as a ZEB2 target with the highest, but inversely correlated, expression level. Remarkably, GALNT3 also exhibited the highest enrichment in the ChIP-qPCR validation assays. Through the analyses of primary tumor cDNA arrays and expO datasets a significant differential expression and a significant inverse correlation between ZEB2 and GALNT3 expression were detected in most of the tumors. We also explored ZEB2 and GALNT3 protein expression using the Human Protein Atlas dataset and, again, observed an inverse correlation in all analyzed tumor types, except malignant melanoma. In contrast to a generally negative or weak ZEB2 expression, we found that most tumor tissues exhibited a strong or moderate GALNT3 expression. Our observation that ZEB2 negatively regulates a GalNAc-transferase (GALNT3) that is involved in O-glycosylation adds another layer of complexity to the role of ZEB2 in cancer progression and metastasis. Proteins glycosylated by GALNT3 may be exploited as novel diagnostics and/or therapeutic targets.
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- 2018
38. Long non-coding RNAs within the tumour microenvironment and their role in tumour-stroma cross-talk
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Alex H. Mirnezami, Graham Packham, George A. Calin, Emre Sayan, Gareth J. Thomas, Filippo Del Vecchio, Martin Pichler, Joamir Hawezi, Gui Han Lee, Marc D. Bullock, John N. Primrose, Rahul Bhome, and Sian Alexandra Pugh
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0301 basic medicine ,Cancer Research ,Stromal cell ,Angiogenesis ,Cancer ,Biology ,medicine.disease ,Microvesicles ,Long non-coding RNA ,Malignant transformation ,Extracellular Matrix ,03 medical and health sciences ,030104 developmental biology ,Oncology ,Stroma ,Neoplasms ,Cancer cell ,Cancer research ,medicine ,Disease Progression ,Tumor Microenvironment ,Humans ,RNA, Long Noncoding ,Stromal Cells ,Signal Transduction - Abstract
Long non-coding RNAs (lncRNAs) are a diverse class of RNA transcripts which have limited protein coding potential. They perform a variety of cellular functions in health, but have also been implicated during malignant transformation. A further theme in recent years is the critical role of the tumour microenvironment and the dynamic interactions between cancer and stromal cells in promoting invasion and disease progression. Whereas the contribution of deregulated lncRNAs within cancer cells has received considerable attention, their significance within the tumour microenvironment is less well understood. The tumour microenvironment consists of cancer-associated stromal cells and structural extracellular components which interact with one another and with the transformed epithelium via complex extracellular signalling pathways. LncRNAs are directly and indirectly involved in tumour/stroma cross-talk and help stimulate a permissive tumour microenvironment which is more conducive for invasive tumour growth. Furthermore, lncRNAs play key roles in determining the phenotype of cancer associated stromal cells and contribute to angiogenesis and immune evasion pathways, extracellular-matrix (ECM) turnover and the response to hypoxic stress. Here we explore the multifaceted roles of lncRNAs within the tumour microenvironment and their putative pathophysiological effects.
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- 2017
39. Suppression of Hedgehog signalling promotes pro-tumourigenic integrin expression and function
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Christian H. Ottensmeier, A. Emre Sayan, Karwan A. Moutasim, Shelia M. Violette, Azzura Greco, Philip Kiely, Graham W. Neill, Joanne Tod, Toby Mellows, Massimiliano Mellone, Veronika Jenei, Gareth J. Thomas, Marie-Antoinette Lopez, Paul H. Weinreb, Karen Sapienza, and John Marshall
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Stromal cell ,integumentary system ,biology ,Integrin ,Cancer ,medicine.disease ,Pathology and Forensic Medicine ,GLI1 ,Pancreatic cancer ,Immunology ,biology.protein ,medicine ,Cancer research ,Basal cell carcinoma ,Myofibroblast ,Hedgehog - Abstract
Aberrant Hedgehog (Hh) signalling has been reported in a number of malignancies, particularly basal cell carcinoma (BCC) of the skin. Clinical trials of Hh inhibitors are underway in many cancers, and these have produced significant clinical benefit in BCC patients, although regrowth of new, or clinically aggressive, variants, as well as development of secondary malignancies, has been reported. ?v?6 integrin is expressed in many cancers, where it has been shown to correlate with an aggressive tumour phenotype and poor prognosis. We have previously reported ?v?6 up-regulation in aggressive, morphoeic BCC variants, where it modulates the stromal response and induces invasion. To examine a possible link between Hh and ?v?6 function, we generated BCC models, overexpressing Gli1 in immortalized keratinocytes (NTert1, HaCaT). Unexpectedly, we found that suppressing Gli1 significantly increased ?v?6 expression. This promoted tumour cell motility and also stromal myofibroblast differentiation through integrin-dependent TGF-?1 activation. Gli1 inhibited ?v?6 expression by suppressing TGF-?1-induced Smad2/3 activation, blocking a positive feedback loop maintaining high ?v?6 levels. A similar mechanism was observed in AsPC1 pancreatic cancer cells expressing endogenous Gli1, suggesting a common mechanism across tumour types. In vitro findings were supported using human clinical samples, where we showed an inverse correlation between ?v?6 and Gli1 expression in different BCC subtypes and pancreatic cancers. In summary, we show that expression of Gli1 and ?v?6 inversely correlates in tumours in vivo, and Hh targeting up-regulates TGF-?1/Smad2/3-dependent ?v?6 expression, promoting pro-tumourigenic cell functions in vitro. These results have potential clinical significance, given the reported recurrence of BCC variants and secondary malignancies in patients treated by Hh targeting.
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- 2014
40. Profiling the MicroRNA Payload of Exosomes Derived from Ex Vivo Primary Colorectal Fibroblasts
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Alex H. Mirnezami, Massimiliano Mellone, Karen Pickard, Rebecca W. Goh, A. Emre Sayan, and Rahul Bhome
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0301 basic medicine ,Colorectal cancer ,Colon ,Primary Cell Culture ,Biology ,Exosomes ,Real-Time Polymerase Chain Reaction ,Exosome ,Article ,03 medical and health sciences ,Stroma ,microRNA ,medicine ,Biomarkers, Tumor ,Humans ,Cells, Cultured ,Oligonucleotide Array Sequence Analysis ,Tumor microenvironment ,Gene Expression Profiling ,Rectum ,Fibroblasts ,medicine.disease ,Microvesicles ,MicroRNAs ,030104 developmental biology ,Cancer cell ,Immunology ,Cancer research ,Colorectal Neoplasms ,Ex vivo - Abstract
The tumor microenvironment is a heterogeneous and dynamic network that exists between cancer and stroma, playing a critical role in cancer progression. Certain tumorigenic signals such as microRNAs are derived from the stroma and conveyed to cancer cells (and vice versa) in nanoparticles called exosomes. Their identification and characterization is an important step in better understanding cellular cross talk and its consequences. To this end we describe how to culture primary ex vivo derived fibroblasts from colorectal tissue, isolate their exosomes, extract exosomal RNA and perform microRNA profiling.
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- 2016
41. A 19S proteasomal subunit cooperates with an ERK MAPK-regulated degron to regulate accumulation of Fra-1 in tumour cells
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Julian L. Pakay, Yan Y. Yip, Omer Gilan, Ross D. Hannan, Amardeep S. Dhillon, Walter Kolch, John M. Mariadason, Jeannine Diesch, Emre Sayan, and Eugene Tulchinsky
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MAPK/ERK pathway ,Proteasome Endopeptidase Complex ,Cancer Research ,MAP Kinase Signaling System ,Biology ,Fra-1 ,Molecular oncology ,Growth factor receptor ,Cell Line, Tumor ,Neoplasms ,Genetics ,cancer ,Humans ,Extracellular Signal-Regulated MAP Kinases ,Molecular Biology ,Transcription factor ,Kinase ,turnover ,Cell cycle ,Cell biology ,TBP-1 ,Gene Expression Regulation, Neoplastic ,Transcription Factor AP-1 ,ERK ,ras Proteins ,ATPases Associated with Diverse Cellular Activities ,Degron ,Signal transduction ,Proto-Oncogene Proteins c-fos ,RAS ,Signal Transduction - Abstract
Fos-related antigen-1 (Fra-1) is a member of the Activator Protein-1 (AP-1) transcription factor superfamily that is overexpressed in a variety of cancers, including colon, breast, lung, bladder and brain. High Fra-1 levels are associated with enhanced cell proliferation, survival, migration and invasion. Despite its frequent overexpression, the molecular mechanisms that regulate the accumulation of Fra-1 proteins in tumour cells are not well understood. Here, we show that turnover of Fra-1, which does not require ubiquitylation, is cooperatively regulated by two distinct mechanisms—association with the 19S proteasomal subunit, TBP-1, and by a C-terminal degron, which acts independently of TBP-1, but is regulated by RAS–ERK (extracellular signal-regulated kinase) signalling. TBP-1 depletion stabilized Fra-1 and further increased its levels in tumour cells expressing RAS–ERK pathway oncogenes. These effects correlated with increased AP-1 transcriptional activity. We suggest that during Fra-1 degradation, association with TBP-1 provides a mechanism for ubiquitin-independent proteasomal recognition, while the C terminus of the protein regulates its subsequent proteolytic processing. This work was supported by grants from the National Health and Medical Research Council of Australia & SFI Deposited by bulk import
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- 2011
42. Assessment of Nuclear ZEB2 as a Biomarker for Colorectal Cancer Outcome and TNM Risk Stratification
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Ricardo DeMateos, Sophie White, Alex H. Mirnezami, Gareth J. Thomas, A. Emre Sayan, Katherine Emo, Karwan A. Moutasim, Rahul Sreekumar, Ashish Patel, Eugene Tulchinsky, Tamer Yagci, John N. Primrose, and Scott Harris
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Male ,0301 basic medicine ,Oncology ,medicine.medical_specialty ,Colorectal cancer ,Disease ,TNM staging system ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Internal medicine ,Biomarkers, Tumor ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Survival analysis ,Aged ,Neoplasm Staging ,Zinc Finger E-box Binding Homeobox 2 ,Aged, 80 and over ,business.industry ,General Medicine ,Middle Aged ,Nomogram ,Prognosis ,medicine.disease ,Immunohistochemistry ,Survival Analysis ,3. Good health ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cohort ,Biomarker (medicine) ,Female ,Colorectal Neoplasms ,business - Abstract
Importance: At present, patients with colorectal cancer (CRC) are risk stratified using TNM histologic features. More recently, an association between a mesenchymal phenotype and a high risk of disease recurrence and micrometastases has been recognized.Objective: To investigate the association of the epithelial to mesenchymal transition (EMT)-inducing transcription factor ZEB2 (zinc finger E box-binding homeobox 2), survival outcomes, and the efficacy of ZEB2 as a biomarker when added as refinement to TNM staging after curative intent surgery for CRC.Design, Setting, and Participants: ZEB2 expression was assessed using a previously validated scoring system as part of a prospective, observational, masked diagnostic study from January 1, 2008, to December 31, 2013. Data were prospectively collected and analyzed for association with oncologic outcomes from January 1, 2017, to December 31, 2018. An initial test cohort from an academic university medical center of 126 consecutive patients with CRC and, subsequently, an independent validation cohort of 210 patients were examined. ZEB2 positivity was scored by 2 independent, masked pathologists. External validity was tested using an open access gene expression portal. Nomograms were developed with or without ZEB2.Main Outcomes and Measures: Systemic and local recurrence of CRC.Results: The test cohort consisted of 126 consecutive patients (mean [SD] age, 72.7 [11.7] years; 61 [48.4%] male) and the validation cohort of 210 patients (mean [SD] age, 72.0 [10.6] years; 111 [52.9%] male). A total of 52 tumors (41.3%) in the test cohort and 104 (49.5%) in the validation cohort were scored nuclear ZEB2 positive. Survival analysis by the log-rank test found that ZEB2 expression was associated with a significant reduction in overall survival and disease-free survival in both cohorts. Cox proportional hazards regression analysis highlighted ZEB2 as an independent biomarker of shorter overall survival and disease-free survival. Analysis of node-negative disease (n = 222) identified ZEB2 as an independent biomarker of early recurrence and reduced survival. External validation confirmed these findings. Addition of ZEB2 expression to nomograms composed of conventional TNM risk factors improved the ability to identify patients at high risk of recurrence demonstrated by the improvement in concordance index in both test (0.73 to 0.77) and validation (0.82 to 0.87) cohorts.Conclusions and Relevance: The findings suggest that expression of ZEB2 is associated with poor oncologic outcome and distant recurrence. The study also found that the addition of ZEB2 to existing TNM classification improved the ability to stratify patients for risk of recurrence. The results of this study suggest that addition of ZEB2 expression status to the TNM staging system improves the ability to stratify patients at high risk of recurrence.
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- 2018
43. p73 and p63 regulate the expression of fibroblast growth factor receptor 3
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Berna S. Sayan, Maria Paola Cerù, Barbara D'Angelo, A. Emre Sayan, Richard A. Knight, Annamaria Cimini, Gerry Melino, and Paola Tucci
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Transcriptional Activation ,Cell death ,Gene isoform ,tumor ,Skin Neoplasms ,receptor ,APOPTOSIS ,FGFR3 ,Molecular Sequence Data ,Biophysics ,Biology ,medicine.disease_cause ,Fibroblast growth factor ,Biochemistry ,Downregulation and upregulation ,Cell Line, Tumor ,fibroblast growth factor ,medicine ,Humans ,Receptor, Fibroblast Growth Factor, Type 3 ,Amino Acid Sequence ,Molecular Biology ,Gene ,Transcription factor ,Settore BIO/11 ,Tumor Suppressor Proteins ,Nuclear Proteins ,Tumor Protein p73 ,gene expression regulation ,cell line ,Cell Biology ,Fibroblast growth factor receptor 3 ,neoplastic ,type 3 ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,stomatognathic diseases ,Urinary Bladder Neoplasms ,Fibroblast growth factor receptor ,Trans-Activators ,Cancer research ,Carcinogenesis ,Transcriptional activation ,gene expression regulation, neoplastic ,tumor suppressor proteins ,dna-binding proteins ,humans ,cell line, tumor ,nuclear proteins ,skin neoplasms ,molecular sequence data ,receptor, fibroblast growth factor, type 3 ,amino acid sequence ,trans-activators ,urinary bladder neoplasms ,Transcription Factors - Abstract
p53, p63 and p73 make a family of transcription factors that play a vital role in development and cancer. All p53 family members have more than one promoter producing Transactivating (TA) and Dominant Negative (DeltaN) isoforms and their mRNAs are subjected to extensive splicing at 3' end to produce multiple protein products. p53 is usually inactivated by point mutations during tumorigenesis, whereas the expression levels and p63 and p73 are modulated to give tumor cells a selective advantage. In this study, aiming to find novel targets of the p53 family members, we identified FGFR3 as a gene transcriptionally controlled by p63 and p73. FGFR3 has been implicated in development and tumor biology as activating mutations of this gene was described in skeletal disorders, non-invasive skin conditions and superficial bladder cancers. We found that TAp73, TAp63 and DeltaNp63 was capable of inducing FGFR3. siRNA mediated downregulation of DeltaNp63 decreased endogenous FGFR3 protein levels. Our findings of this new link between p53 family proteins and FGFR3 may help understanding the transition of superficial bladder cancers to an invasive phenotype.
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- 2010
44. Direct Repression of Cyclin D1 by SIP1 Attenuates Cell Cycle Progression in Cells Undergoing an Epithelial Mesenchymal Transition
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Marina Kriajevska, Tatyana Chernova, Jakob Mejlvang, J. Kilian Mellon, Geert Berx, Eugene Tulchinsky, A. Emre Sayan, and Cindy Vandewalle
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Transcription, Genetic ,Cyclin D ,Cyclin A ,Cyclin B ,Down-Regulation ,Nerve Tissue Proteins ,Mesoderm ,Cyclin D1 ,Cell Line, Tumor ,Humans ,Epithelial–mesenchymal transition ,Promoter Regions, Genetic ,Molecular Biology ,biology ,Cell Cycle ,RNA-Binding Proteins ,Epithelial Cells ,Articles ,Cell Biology ,Cell cycle ,Science General ,Cadherins ,Cell biology ,Mutation ,biology.protein ,A431 cells ,Cyclin A2 - Abstract
Zinc finger transcription factors of the Snail/Slug and ZEB-1/SIP1 families control epithelial-mesenchymal transitions in development in cancer. Here, we studied SIP1-regulated mesenchymal conversion of epidermoid A431 cells. We found that concomitant with inducing invasive phenotype, SIP1 inhibited expression of cyclin D1 and induced hypophosphorylation of the Rb tumor suppressor protein. Repression of cyclin D1 was caused by direct binding of SIP1 to three sequence elements in the cyclin D1 gene promoter. By expressing exogenous cyclin D1 in A431/SIP1 cells and using RNA interference, we demonstrated that the repression of cyclin D1 gene by SIP1 was necessary and sufficient for Rb hypophosphorylation and accumulation of cells in G1 phase. A431 cells expressing SIP1 along with exogenous cyclin D1 were highly invasive, indicating that SIP1-regulated invasion is independent of attenuation of G1/S progression. However, in another epithelial-mesenchymal transition model, gradual mesenchymal conversion of A431 cells induced by a dominant negative mutant of E-cadherin produced no effect on the cell cycle. We suggest that impaired G1/S phase progression is a general feature of cells that have undergone EMT induced by transcription factors of the Snail/Slug and ZEB-1/SIP1 families.
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- 2007
45. A Top Down View of Tumor Microenvironment: Structure, Cells and Signalling
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Alex H. Mirnezami, Rahul Bhome, Marc D. Bullock, John N. Primrose, A. Emre Sayan, Rebecca W. Goh, and Hajir A. Al Saihati
- Subjects
Cell signaling ,Tumor microenvironment ,Stromal cell ,microRNA ,Cancer-associated fibroblast ,Mini Review ,Mesenchymal stem cell ,Cell Biology ,Biology ,Cancer stroma ,Cell biology ,Extracellular Matrix ,Extracellular matrix ,MicroRNAs ,Immune system ,Stroma ,Oncology ,lcsh:Biology (General) ,Immunology ,Tumor Microenvironment ,lcsh:QH301-705.5 ,Developmental Biology - Abstract
It is well established that the tumour microenvironment contributes to cancer progression. Stromal cells can be divided into mesenchymal, vascular and immune. Signalling molecules secreted by the tumour corrupts these cells to create ‘activated’ stroma. Equally, the extracellular matrix contributes to tumour development and invasion by forming a biologically active scaffold. In this review we describe the key structural, cellular and signalling components of the tumour microenvironment with a perspective on stromal soluble factors and microRNAs.
- Published
- 2015
46. Stratifying risk of recurrence in stage II colorectal cancer using deregulated stromal and epithelial microRNAs
- Author
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A. Emre Sayan, Marc D. Bullock, John N. Primrose, Graham Packham, George A. Calin, Richard Mitter, Karen Pickard, Alex H. Mirnezami, Cristina Ivan, and Gareth J. Thomas
- Subjects
Oncology ,Male ,Risk ,medicine.medical_specialty ,Stromal cell ,Colorectal cancer ,Colon ,Biology ,Stroma ,Internal medicine ,microRNA ,medicine ,stroma ,Biomarkers, Tumor ,tumor microenvironment ,Humans ,RNA, Messenger ,Neoplasm Metastasis ,Aged ,Neoplasm Staging ,Skin ,Tumor microenvironment ,Oncogene ,Gene Expression Profiling ,Cancer ,Middle Aged ,medicine.disease ,Prognosis ,Gene expression profiling ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,Disease Progression ,Female ,Neoplasm Recurrence, Local ,Stromal Cells ,Colorectal Neoplasms ,Microdissection ,Research Paper - Abstract
MicroRNAs (miRNAs) enable colonic epithelial cells to acquire malignant characteristics and metastatic capabilities. Recently, cancer relevant miRNAs deregulated during disease progression have also been identified in tumor-associated stroma. By combining laser-microdissection (LMD) with high-throughput screening and high-sensitivity quantitation techniques, miRNA expression in colorectal cancer (CRC) specimens and paired normal colonic tissue was independently characterized in stromal and epithelial tissue compartments. Notably, deregulation of the key oncogene miR-21 was identified exclusively as a stromal phenomenon and miR-106a, an epithelial phenomenon in the malignant state. MiRNAs identified in this study successfully distinguished CRC from normal tissue and metastatic from non-metastatic tumor specimens. Furthermore, in a separate cohort of 50 consecutive patients with CRC, stromal miR-21 and miR-556 and epithelial miR-106a expression predicted short disease free survival (DFS) and overall survival (OS) in stage II disease: miR-21 (DFS: HR = 2.68, p = 0.015; OS: HR = 2.47, p = 0.029); miR-556 (DFS: HR = 2.60, p = 0.018); miR-106a (DFS: HR = 2.91, p = 0.008; OS: HR = 2.25, p = 0.049); combined (All High vs. All Low. DFS: HR = 5.83, p = 0.002; OS: HR = 4.13, p = 0.007). These data support the notion that stromal as well as epithelial miRNAs play important roles during disease progression, and that mapping patterns of deregulated gene expression to the appropriate tumor strata may be a valuable aid to therapeutic decision making in CRC.
- Published
- 2015
47. New antibodies recognizing p73: Comparison with commercial antibodies
- Author
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Borek Vojtesek, Andrea Paradisi, A. Emre Sayan, Gerry Melino, Eleonora Candi, and Richard A. Knight
- Subjects
Gene isoform ,Immunoprecipitation ,Blotting, Western ,Biophysics ,Biochemistry ,Antibodies ,Cell Line ,Exon ,Humans ,Genes, Tumor Suppressor ,skin and connective tissue diseases ,neoplasms ,Molecular Biology ,Antiserum ,biology ,Immune Sera ,Tumor Suppressor Proteins ,Alternative splicing ,Nuclear Proteins ,Tumor Protein p73 ,Cell Biology ,Molecular biology ,DNA-Binding Proteins ,Blot ,Polyclonal antibodies ,biology.protein ,Antibody - Abstract
p73, unlike p53, is expressed as a number of isomeric forms. Alternative splicing at the 3' end of p73 transcript, together with the usage of a second promoter downstream of exon 3, can generate up to 24 p73 isoforms. Variants lacking the TA domain (DeltaN isoforms) are induced by TAp73 and by p53, and inhibit their transcriptional activity. However, understanding the complex biology of p73 has been handicapped by the lack of high affinity specific antibodies for the different isoforms. Here, we report the characterization, by Western blotting and immunoprecipitation, of three new polyclonal antisera recognizing all p73 isoforms, only DeltaN isoforms or only p73alpha, and which have advantages of affinity and specificity over previously available antibodies.
- Published
- 2005
48. Mechanism of Induction of Apoptosis by p73 and Its Relevance to Neuroblastoma Biology
- Author
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Gerry Melino, Alessandro Terrinoni, Richard A. Knight, A. Emre Sayan, and Mario Rossi
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p53 ,Time Factors ,Cell cycle checkpoint ,Transcription, Genetic ,Apoptosis ,Endoplasmic Reticulum ,Neuroblastoma ,Transactivation ,Models ,Neoplasms ,scotin ,Protein Isoforms ,Genes, Tumor Suppressor ,Tumor Protein p73 ,skin and connective tissue diseases ,bcl-2-Associated X Protein ,Tumor ,Cell Death ,biology ,Settore BIO/12 ,General Neuroscience ,Nuclear Proteins ,Mitochondria ,Cell biology ,DNA-Binding Proteins ,Proto-Oncogene Proteins c-bcl-2 ,Transcription ,Tumor Suppressor ,Programmed cell death ,p73 ,Cell fate determination ,Models, Biological ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Bcl-2-associated X protein ,Genetic ,History and Philosophy of Science ,PUMA ,Cell Line, Tumor ,Humans ,Settore BIO/10 ,neoplasms ,Tumor Suppressor Proteins ,Endoplasmic reticulum ,Membrane Proteins ,Biological ,Genes ,Gene Expression Regulation ,Bax ,apoptosis ,endoplasmic reticulum ,Apoptosis Regulatory Proteins ,Mutation ,Transcription Factors ,Tumor Suppressor Protein p53 ,biology.protein ,Cancer research - Abstract
TP73, as a TP53 homologue, drew the attention of tumor biologists because it is rarely mutated in human cancers and can induce cell cycle arrest and apoptosis by activating genes also regulated by p53. However, TP73 harbors an additional promoter that produces a dominant negative p73 protein (deltaNp73) having the opposite effect of the TAp73 protein. Thus, the regulation of p53 responsive genes in the absence of p53 relies on a critical balance between different p73 gene-derived proteins. Recent reports have described additional complexity in the mechanism of action of transcriptionally active p73 (TAp73) in the induction of cell death. The molecular mechanism through which p73 induces apoptosis involves (i) expression and changes in subcellular localization of scotin, producing an endoplasmic reticulum (ER) stress; and (ii) transactivation of PUMA and Bax, thus determining cell fate. On the contrary, deltaNp73 inhibits apoptosis, thus contributing to the oncogenic potential of neuroblastoma cells.
- Published
- 2004
49. Abstract 2982: Metastatic and non-metastatic colorectal cancer cells differentially regulate fibroblast cell cycle via extracellular vesicles
- Author
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Louise M. House, Stephen M. Thirdborough, Tilman Sanchez-Elsner, Alex H. Mirnezami, Emre Sayan, and Rahul Bhome
- Subjects
MAPK/ERK pathway ,Cancer Research ,Tumor microenvironment ,Stromal cell ,Chemistry ,Mesenchymal stem cell ,Cell cycle ,Cell biology ,medicine.anatomical_structure ,Oncology ,Tumor progression ,medicine ,Cancer-Associated Fibroblasts ,Fibroblast - Abstract
Cancer-associated fibroblasts are critical to tumor progression. There exists a dynamic crosstalk between cancer and stromal compartments, which maintains a permissive tumor microenvironment. Extracellular vesicles (EVs) play a significant role in this intercellular communication. Colorectal cancer (CRC) cells can be categorized according to epithelial-mesenchymal transition (EMT) status, and therefore metastatic capacity. We aimed to investigate the effect of EMT on EV-mediated cancer-fibroblast signaling. CRC cell lines (DLD-1, HCT116, SW620 and SW480) were characterized by western blotting to determine EMT status. EVs were isolated from conditioned media by serial centrifugation and validated by transmission electron microscopy, western blotting and nanoparticle tracking analysis. Fluorescently labeled EVs and cells were detected and evaluated by flow cytometry and fluorescence microscopy. Increasing concentrations of EVs from CRC cells were co-cultured with fibroblasts for 24h. Activation/inhibition of signaling pathways was examined by western blotting. EV microRNA (miRNA) profiles were obtained, validated by qPCR and submitted for target and pathway analysis. DLD-1, HCT116 and SW620 cells express E-cadherin and are considered epithelial, whereas SW480 lacks E-cadherin, expresses ZEB-1, and is considered mesenchymal. EVs were spherical, enriched in ALIX, TSG101, CD63 and had a mean diameter of 90nm. EVs from CRC cells were shown to transfer directly to primary ex vivo patient-derived fibroblasts and fibroblast cell lines. Transfer of EVs from epithelial CRC cells abrogated ERK activity in fibroblasts, even at the lowest concentration, and was associated with reduced fibroblast proliferation, whereas EVs from mesenchymal cells had no effect. MiRNA profiling of EVs from epithelial and mesenchymal CRC cells showed a 10-fold upregulation of miR-143-3p in epithelial compared to mesenchymal EVs. MiRNA target analysis and experimental validation show that miR-143-3p directly targets KRAS and HRAS, providing a potential miRNA-orchestrated mechanism of action for the downregulation of fibroblast ERK activity in the tumor microenvironment. Importantly, CRC cellular ERK activity is not reflected in fibroblasts treated with CRC EVs, suggesting that EVs do not directly transmit ERK protein or mRNA. However, miRNAs are the most stable EV cargo, and we show that epithelial but not mesenchymal CRC EVs contain upregulated miRNAs, which target critical components of the ERK pathway. Downregulation of ERK activity has been shown to induce fibroblast senescence, a phenotype linked to cancer progression. We hypothesize that differential regulation occurs because epithelial CRC cells are juxtaposed with fibroblasts in the tumor core, where senescent cancer associated fibroblasts are frequently observed, whereas mesenchymal CRC cells are at the invasive front or in the circulation. Citation Format: Rahul Bhome, Louise M. House, Tilman Sanchez-Elsner, Stephen M. Thirdborough, Emre Sayan, Alex H. Mirnezami. Metastatic and non-metastatic colorectal cancer cells differentially regulate fibroblast cell cycle via extracellular vesicles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2982. doi:10.1158/1538-7445.AM2017-2982
- Published
- 2017
50. Molecular Profiling of the Invasive Tumor Microenvironment in a 3-Dimensional Model of Colorectal Cancer Cells and Ex vivo Fibroblasts
- Author
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Alexander H. Mirnezami, Gareth Thomas, Graham K. Packham, John N. Primrose, Richard Mitter, Abdulkadir Emre Sayan, Karen M. Pickard, Max Mellone, and Marc D. Bullock
- Subjects
General Immunology and Microbiology ,General Chemical Engineering ,General Neuroscience ,General Biochemistry, Genetics and Molecular Biology - Published
- 2014
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