Researcher:
Gökbayrak, Bengül

Profile Picture
ORCID

Job Title

PhD Student

First Name

Bengül

Last Name

Gökbayrak

Name

Name Variants

Gökbayrak, Bengül

Email Address

Birth Date

Filters

2021 - 20222

Advanced Search

Filter by

Settings

Researcher Of Publications: search.filters.isAuthorOfPublication.b4c51666-3a62-40e7-88f7-44fa27843ecd

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    PublicationOpen Access
    EPIKOL, a chromatin-focused CRISPR/Cas9-based screening platform, to identify cancer-specific epigenetic vulnerabilities
    (Nature Portfolio, 2022) Philpott, Martin; Cribbs, Adam P.; Kung, Sonia H.Y; Bayram, Özlem Yedier; Gökbayrak, Bengül; Kayabölen, Alişan; Aksu, Ali Cenk; Cavga, Ayşe Derya; Cingöz, Ahmet; Kala, Ezgi Yağmur; Karabıyık, Göktuğ; Esin, Beril; Morova, Tunç; Uyulur, Fırat; Önder, Tuğba Bağcı; Syed, Hamzah; Lack, Nathan Alan; Önder, Tamer Tevfik; PhD Student; Faculty Member; Faculty Member; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; Graduate School of Health Sciences; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; 184359; 318138; 120842; 42946
    Dysregulation of the epigenome due to alterations in chromatin modifier proteins commonly contribute to malignant transformation. To interrogate the roles of epigenetic modifiers in cancer cells, we generated an epigenome-wide CRISPR-Cas9 knockout library (EPIKOL) that targets a wide-range of epigenetic modifiers and their cofactors. We conducted eight screens in two different cancer types and showed that EPIKOL performs with high efficiency in terms of sgRNA distribution and depletion of essential genes. We discovered novel epigenetic modifiers that regulate triple-negative breast cancer (TNBC) and prostate cancer cell fitness. We confirmed the growth-regulatory functions of individual candidates, including SS18L2 and members of the NSL complex (KANSL2, KANSL3, KAT8) in TNBC cells. Overall, we show that EPIKOL, a focused sgRNA library targeting similar to 800 genes, can reveal epigenetic modifiers that are essential for cancer cell fitness under in vitro and in vivo conditions and enable the identification of novel anti-cancer targets. Due to its comprehensive epigenome-wide targets and relatively high number of sgRNAs per gene, EPIKOL will facilitate studies examining functional roles of epigenetic modifiers in a wide range of contexts, such as screens in primary cells, patient-derived xenografts as well as in vivo models.
  • Thumbnail Image
    PublicationOpen Access
    Functional mapping of androgen receptor enhancer activity
    (BioMed Central, 2021) Huang, Flora Chia-Chi; Morova, Tunç; Hu, Eugene; Yu, Lok Pak Ivan; Linder, Simon; Hoogstraat, M.; Stelloo, Suzan; Sar, Funda; Van der Poel, Henk; Saffarzadeh, Mohammadali; Le Bihan, Stephane; McConegy, Brian; Y Feng, Felix; Gleave, E. Martin; Bergman, M. Andries; Collins, Colin; Hach, Faraz; Zwart, Wilbert; Emberly, Eldon; N/A; Department of Molecular Biology and Genetics; Özturan, Doğancan; Altıntaş, Umut Berkay; Gökbayrak, Bengül; Lack, Nathan Alan; PhD Student; Faculty Member; Department of Molecular Biology and Genetics; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Graduate School of Health Sciences; Graduate School of Sciences and Engineering; N/A; N/A; N/A; 120842
    Background: androgen receptor (AR) is critical to the initiation, growth, and progression of prostate cancer. Once activated, the AR binds to cis-regulatory enhancer elements on DNA that drive gene expression. Yet, there are 10-100x more binding sites than differentially expressed genes. It is unclear how or if these excess binding sites impact gene transcription. Results: to characterize the regulatory logic of AR-mediated transcription, we generated a locus-specific map of enhancer activity by functionally testing all common clinical AR binding sites with Self-Transcribing Active Regulatory Regions sequencing (STARRseq). Only 7% of AR binding sites displayed androgen-dependent enhancer activity. Instead, the vast majority of AR binding sites were either inactive or constitutively active enhancers. These annotations strongly correlated with enhancer-associated features of both in vitro cell lines and clinical prostate cancer samples. Evaluating the effect of each enhancer class on transcription, we found that AR-regulated enhancers frequently interact with promoters and form central chromosomal loops that are required for transcription. Somatic mutations of these critical AR-regulated enhancers often impact enhancer activity. Conclusions: using a functional map of AR enhancer activity, we demonstrated that AR-regulated enhancers act as a regulatory hub that increases interactions with other AR binding sites and gene promoters.