Gün Kaynar
MSc CS
Bilkent University

Email Curriculum Vitae

About

I am Gün Kaynar

I am Computer Science MSc student at Bilkent University where I am fortunate to work with Dr. Ercument Cicek. I am working as a Research and Teaching Assistant at CICEKLAB, Bilkent University, Ankara.
MSc in Computer Engineering at Bilkent University (2021-2024)
BSc in Molecular Biology and Genetics at Bogazici University (2015-2021)
Exchange student in Biology at Universitat de Barcelona (2020)
Izmir Atatürk High School (2011-2015)

My research interests include:


  • Computational Biology
  • Bioinformatics
  • Biologically-Informed Models
  • Deep Learning
  • CNV Calling
  • Cancer Biology
  • NMR Spectroscopy
  • Metabolomics
  • Machine Learning
  • Genomics

Publications

Journal Papers

  • ECOLE: Learning to call copy number variants on whole exome sequencing data

    Nature Communications, 2024
    Mandiracioglu B, Ozden F, Kaynar G, Yilmaz MA, Alkan C, Cicek AE
    Article, Scholar

    Abstract

    Copy number variants (CNV) are shown to contribute to the etiology of several genetic disor­ders. Accurate detection of CNVs on whole exome sequencing (WES) data has been a long sought-after goal for use in clinics. This was not possible despite recent improvements in performance because algo­rithms mostly suffer from low precision and even lower recall on expert-curated gold standard call sets. Here, we present a deep learning-based somatic and germline CNV caller for WES data, named ECOLE. Based on a variant of the transformer architecture, the model learns to call CNVs per exon, using high-confidence calls made on matched WGS samples. We further train and fine-tune the model with a small set of expert calls via transfer learning. We show that ECOLE achieves high performance on human ex­pert labeled data for the first time with 68.7% precision and 49.6% recall. This corresponds to precision and recall improvements of 18.7% and 30.8% over the next best-performing methods, respectively. We also show that the same fine-tuning strategy using tumor samples enables ECOLE to detect RT-qPCR validated variations in bladder cancer samples without the need for a control sample. ECOLE is available at https://github.com/ciceklab/ECOLE.

  • PiDeeL: Metabolic Pathway-Informed Deep Learning Model for Survival Analysis and Pathological Classification of Gliomas

    Bioinformatics, 2023
    Kaynar G, Cakmakci D, Bund C, Todeschi J, Namer IJ, Cicek AE
    Article, Scholar, ResearchGate

    Abstract

    Online assessment of tumor characteristics during surgery is important and has the potential to establish an intraoperative surgeon feedback mechanism. With the availability of such feedback, surgeons could decide to be more liberal or conservative regarding the resection of the tumor. While there are methods to perform metabolomics-based online tumor pathology prediction, their model complexity and, in turn, the predictive performance is limited by the small dataset sizes. Furthermore, the information conveyed by the feedback provided on the tumor tissue could be improved both in terms of content and accuracy. In this study, we propose a metabolic pathway-informed deep learning model, PiDeeL, to perform survival analysis and pathology assessment based on metabolite concentrations. We show that incorporating pathway information into the model architecture substantially reduces parameter complexity and achieves better survival analysis and pathological classification performance. With these design decisions, we show that PiDeeL improves tumor pathology prediction performance of the state-of-the-art in terms of the Area Under the ROC Curve (AUC-ROC) by 3.38% and the Area Under the Precision-Recall Curve (AUC-PR) by 4.06%. Similarly, with respect to the time-dependent concordance index (c-index), we observe that PiDeeL achieves better survival analysis performance (improvement up to 4.3%) when compared to the state-of-the-art. Moreover, we show that importance analyses performed on input metabolite features as well as pathway-specific hidden-layer neurons of PiDeeL provide insights into tumor metabolism. We foresee that the use of this model in the surgery room will help surgeons adjust the surgery plan on the fly and will result in better prognosis estimates tailored to surgical procedures. The code is released at https://github.com/ciceklab/PiDeeL. The data used in this study is released at https://zenodo.org/record/7228791.

  • Targeted Metabolomics Analyses for Brain Tumor Margin Assessment During Surgery

    Bioinformatics, 2022
    Cakmakci D*, Kaynar G*, Bund C, Piotto M, Proust F, Namer IJ, Cicek AE

    * = joint first authors

    Article, Scholar, ResearchGate

    Abstract

    Identification and removal of micro-scale residual tumor tissue during brain tumor surgery are key for survival in glioma patients. For this goal, High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance (HRMAS NMR) spectroscopy-based assessment of tumor margins during surgery has been an effective method. However, the time required for metabolite quantification and the need for human experts such as a pathologist to be present during surgery are major bottlenecks of this technique. While machine learning techniques that analyze the NMR spectrum in an untargeted manner (i.e. using the full raw signal) have been shown to effectively automate this feedback mechanism, high dimensional and noisy structure of the NMR signal limits the attained performance. In this study, we show that identifying informative regions in the HRMAS NMR spectrum and using them for tumor margin assessment improves the prediction power. We use the spectra normalized with the ERETIC (electronic reference to access in vivo concentrations) method which uses an external reference signal to calibrate the HRMAS NMR spectrum. We train models to predict quantities of metabolites from annotated regions of this spectrum. Using these predictions for tumor margin assessment provides performance improvements up to 4.6% the Area Under the ROC Curve (AUC-ROC) and 2.8% the Area Under the Precision-Recall Curve (AUC-PR). We validate the importance of various tumor biomarkers and identify a novel region between 7.97 ppm and 8.09 ppm as a new candidate for a glioma biomarker. The code is released at https://github.com/ciceklab/targeted_brain_tumor_margin_assessment. The data underlying this article are available in Zenodo, at https://doi.org/10.5281/zenodo.5781769.

  • Peer-Reviewed Conference Proceedings

  • Poster, PiDeeL: Pathway-Informed Deep Learning Model for Survival Analysis and Pathological Classification of Gliomas

    HIBIT (16th The International Symposium on Health Informatics and Bioinformatics), Ankara, Turkey, October 2023
    Kaynar G, Cakmakci D, Bund C, Todeschi J, Namer IJ, Cicek AE
    Poster, bioRxiv, Scholar, ResearchGate
  • Conference Paper, ECOLE: Learning to call copy number variants on whole exome sequencing data

    HIBIT (16th The International Symposium on Health Informatics and Bioinformatics), Ankara, Turkey, October 2023
    Mandiracioglu B, Ozden F, Kaynar G, Yilmaz MA, Alkan C, Cicek AE
    bioRxiv, Scholar
  • Conference Paper, Pathway-informed deep learning model for survival analysis and pathological classification of gliomas

    RECOMB-CCB (The 15th RECOMB Satellite Workshop on Computational Cancer Biology), Istanbul, Turkey, April 2023.
    Kaynar G, Cakmakci D, Bund C, Todeschi J, Namer IJ, Cicek AE
    Talk, bioRxiv, Scholar, ResearchGate
  • Poster, Targeted Metabolomics Analyses for Brain Tumor Margin Assessment During Surgery

    RECOMB (27th Annual International Conference on Research in Computational Molecular Biology), Istanbul, Turkey, April 2023.
    Cakmakci D, Kaynar G, Bund C, Piotto M, Proust F, Namer IJ, Cicek AE
    Poster, Article, Scholar, ResearchGate
  • Academic

    Experience

  • 2021-2024
    Graduate Research Assistant
    Computer Engineering Department, CICEKLAB, Bilkent University, Ankara, Turkey
  • 2021-2024
    Graduate Teaching Assistant
    Computer Engineering Department, Bilkent University, Ankara, Turkey
  • 2019-2020
    Undergraduate Research Intern
    CICEKLAB, under the supervision of Dr. Ercument Cicek,
    Computer Engineering Department, Bilkent University, Ankara, Turkey
  • 2018
    Undergraduate Research Intern
    Center for Proteomics and Bioinformatics, under the supervision of Prof. Mark Chance,
    Case Western Reserve University, Cleveland, OH, USA.
  • Reviewer

  • RECOMB 2024
    28th Annual International Conference on Research in Computational Molecular Biology
  • RECOMB 2023
    27th Annual International Conference on Research in Computational Molecular Biology
  • ACM BCB 2022
    The 13th ACM Conference on Bioinformatics, Computational Biology, and Health Informatics
  • ISBRA20223
    18th International Symposium on Bioinformatics Research and Applications
  • ACM TCBB
    IEEE/ACM Transactions on Computational Biology and Bioinformatics
  • Volunteer

  • RECOMB 2023
    27th Annual International Conference on Research in Computational Molecular Biology
  • RECOMB-SEQ 2023
    The 13th RECOMB Satellite Conference on Biological Sequence Analysis
  • RECOMB-CCB
    The 15th RECOMB Satellite Workshop on Computational Cancer Biology
  • RECOMB-CG
    The 20th RECOMB Satellite Conference on Comparative Genomics
  • RECOMB-Genetics 2023
    The 11th RECOMB Satellite Workshop on Computational Methods in Genetics
  • BIO-Arch
    Workshop on Hardware Acceleration of Bioinformatics Workloads
  • Teaching

    Software and
    Paper Implementations

    Certifications

    AWS Educate Machine Learning - DeepRacer

    Amazon Web Services, March 2023

    AI Programming with Python Nanodegree

    Udacity, November 2022

    Game Theory

    Matthew O. Jackson, Kevin Leyton-Brown, Yoav Shoham, Stanford University, September 2022

    AWS Machine Learning Foundations

    Amazon Web Services, August 2022

    AI for Medicine Specialization

    Pranav Rajpurkar, Harvard University, DeepLearning.ai
  • AI for Medical Diagnosis May 2022
  • AI For Medical Treatment June 2022
  • AI for Medical Prognosis June 2022
  • Machine Learning

    Andrew NG, Stanford University, October 2021

    Introduction to Computational Thinking and Data Science

    John Guttag, Massachusetts Institute of Technology, October 2018

    Introduction to Computer Science and Programming Using Python

    Eric Grimson, Massachusetts Institute of Technology, August 2018

    Machine Learning and Bioinformatics Workshop

    Bogazici University, July 2018

    Contact

    gunkaynar [at] gmail.com
    gun.kaynar [at] bilkent.edu.tr