Research

Research Areas

Our work spans computational toxicology, precision oncology, and mechanistic modeling of rare diseases, connecting computational models with preclinical and clinical research.

Publications

Publications & Preprints

Poster Presentation

Transcriptional Architecture of Ferroptosis Resistance in Chordoma: Single-Cell Resolution Reveals an Extreme GPX4 Dependency and a Dormant SREBF1-ACSL4 Axis

Ozge A. Cavus1, Aysegul Kuskucu2, Omer F. Bayrak2

1 AI Istanbul Research Group, Istanbul, Turkey
2 Yeditepe University, Department of Medical Genetics, Istanbul, Turkey
European Society of Human Genetics (ESHG) Congress 2026Gothenburg, Sweden
Abstract

Chordoma is a rare, chemo-resistant bone sarcoma characterized by slow growth and a high proportion of G0 phase cells. Despite aggressive clinical recurrence, the metabolic dependencies and intrinsic resistance mechanisms against non-apoptotic cell death pathways such as ferroptosis remain elusive; bulk sequencing fails to isolate these signals due to high stromal contamination. We analyzed high-resolution scRNA-seq datasets from primary chordoma tissues and digitally isolated 9,157 tumor cells expressing the chordoma-specific diagnostic marker TBXT (Brachyury). Lipid remodeling, iron metabolism, and antioxidant defense networks were mapped at single-cell resolution with rigorous statistical thresholding to account for transcriptomic dropout. Chordoma cells exhibit profound transcriptional "metabolic lockdown": the SREBF1-ACSL4 axis driving polyunsaturated fatty acid synthesis is dormant at baseline (Pearson r=0.017), while 74.9% of TBXT⁺ cells show extreme stoichiometric dominance of GPX4 over ACSL4. The system xc⁻ antiporter is functionally silent (mean SLC7A11: 0.0067), and intracellular iron pools appear sequestered (FTH1/FTL ratio = 3.60, low IRP signature). High intercellular coefficient of variation in ER stress markers (e.g., XBP1 CV=1.24) indicates a hidden homeostatic vulnerability. Chordoma avoids lipid peroxidation through a transcriptionally static, single-point reliance on GPX4 combined with an inactive lipid-reprogramming pathway — not through dynamic multi-layered defense. These findings provide a genetic rationale that baseline chordoma is resistant to conventional ferroptosis inducers but highly vulnerable if static ER/lipid homeostasis can be disrupted.

Keywords
Chordoma; Ferroptosis; GPX4; Single-Cell RNA-seq; TBXT; SREBF1; ACSL4; Rare Bone Tumors; Metabolic Lockdown
Poster Presentation

AI-Driven Reclassification of 9,534 Germline Variants of Uncertain Significance (VUS) in ATM and PALB2: Unveiling Actionable Targets for Precision Oncology

Aysegul Kuskucu2, Ozge A. Cavus1

1 AI Istanbul Research Group, Istanbul, Turkey
2 Yeditepe University, Department of Medical Genetics, Istanbul, Turkey
ESMO Targeted Anticancer Therapies Congress 2026Paris, France • March 16-18, 2026
Abstract

This study presents an AI-driven approach to reclassify 9,534 germline Variants of Uncertain Significance (VUS) in ATM and PALB2 genes. By leveraging proteome-wide computational methods, we identify actionable targets for precision oncology, potentially expanding the eligible patient population for PARP inhibitor therapies. Our findings demonstrate the power of AI in resolving the clinical ambiguity of VUS classifications, transforming uncertain genetic findings into actionable therapeutic opportunities.

Keywords
Variants of Uncertain Significance; VUS Reclassification; ATM; PALB2; PARP Inhibitors; Precision Oncology; AI in Oncology; Germline Variants
Published

Beyond Deep Learning Dominance: A Scaffold-Aware Hybrid Framework for Robust Toxicity Prediction in Data-Scarce Regimes

Ozge A. Cavus1, Aysegul Kuskucu2

1 AIstanbul Research Group, Istanbul, Turkey
2 Department of Medical Genetics, Yeditepe University School of Medicine, Istanbul, Turkey
ChemRxiv2025DOI: 10.26434/chemrxiv-2026-f6g15
Abstract

Computational toxicology plays a pivotal role in modern drug discovery and environmental risk assessment; however, the reliability of predictive models on unseen chemical scaffolds remains a critical bottleneck. Deep learning architectures, despite their prevalence, are susceptible to 'silent failures'—yielding high-confidence errors on out-of-distribution data—which poses significant risks in safety-critical applications. In this study, we propose a 'Safe-by-Design' hybrid framework to mitigate this epistemic uncertainty. Rather than relying on a single algorithmic paradigm, we integrate the explicit structural 'memory' of classical Random Forests with the topological 'intuition' of Graph Neural Networks (GNNs) via a transparent Stacking Ensemble (Logistic Regression) functioning as a Mixture of Experts (MoE). Evaluated across 12 Tox21 endpoints using a rigorous 5-seed benchmarking protocol under Nested Scaffold Split, our analysis demonstrates that classical models serve as an essential robustness layer in data-scarce regimes.

Keywords
Safe-by-Design AI; Epistemic Uncertainty; Computational Toxicology; QSAR; Graph Neural Networks; Mixture of Experts; Scaffold Split; Tox21
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Under Review

Multi-Omics Integration for Therapeutic Target Discovery in Rare Bone Tumors: A Computational Approach

AI Istanbul Research Group1, Yeditepe University Medical Genetics Team2

1 AI Istanbul Research Group, Istanbul, Turkey
2 Yeditepe University, Department of Medical Genetics, Istanbul, Turkey
Chordoma Foundation Research Initiative2025
Abstract

Rare bone tumors, including chordoma and sarcoma, present significant therapeutic challenges due to limited treatment options. This research leverages multi-omics data integration to identify novel therapeutic targets. Using advanced computational methods, we analyzed genomic, transcriptomic, and proteomic data to uncover potential druggable pathways specific to these rare malignancies.

Keywords
Chordoma; Sarcoma; Multi-Omics; Therapeutic Targets; Rare Diseases; Computational Biology
Ongoing Research

Uncovering Intrinsic Resistance Mechanisms in Antibody-Drug Conjugate Therapies for Lung Adenocarcinoma

AI Istanbul Research Group1, Collaborators2

1 AI Istanbul Research Group, Istanbul, Turkey
2 Yeditepe University, Department of Medical Genetics, Istanbul, Turkey
Precision Oncology2025
Abstract

This study investigates the intrinsic resistance mechanisms in antibody-drug conjugate (ADC) therapies for lung adenocarcinoma. Through comprehensive genomic analysis, we identified a novel 1p32 co-deletion syndrome involving TACSTD2 and CDKN2C genes, which contributes to resistance in TROP2-targeted therapies. Our findings propose a novel inhibitor as a potential rescue strategy for TROP2-negative patients.

Keywords
Lung Adenocarcinoma; ADC Therapy; Resistance Mechanisms; TACSTD2; CDKN2C; Precision Oncology
Programmes

Research Programmes

01

Computational Toxicology

Safe-by-Design AI & Hybrid Intelligence

Overview

We mitigate epistemic uncertainty in drug discovery by developing hybrid architectures. Combining Graph Neural Networks (GNNs) with statistical experts, we engineer 'fail-safe' models to predict toxicity with rigorous, reproducible validation.

Key Technologies & Methods

  • Hybrid Mixture of Experts (MoE): Fusing the topological intuition of Graph Neural Networks (GNNs) with the explicit memory of Random Forests.
  • Epistemic Uncertainty Management: A "Safe-by-Design" framework engineered to prevent silent failures on unseen chemical scaffolds.
  • Tox21 Benchmarking: Competitive precision-recall and stability across 12 critical toxicity endpoints in Tox21 benchmarking.
02

Precision Oncology

Drug Resistance & Variant Interpretation

Overview

We decode the molecular logic of treatment failure. From reclassifying Variants of Uncertain Significance (VUS) in DDR genes to uncovering intrinsic resistance mechanisms in Antibody-Drug Conjugates (ADCs), we turn genomic complexity into actionable targets.

Key Discoveries & Methods

  • AI-Driven Variant Resolution: Utilizing proteome-wide AI to reclassify >9,500 VUS in DDR genes (ATM/PALB2), identifying hidden candidates for PARP inhibitors.
  • Decoding Intrinsic Resistance: Uncovering the "1p32 Co-Deletion" syndrome in lung cancer—a genetic blind spot driving resistance to TROP2-ADCs.
  • Synthetic Lethality: Transforming molecular liabilities into therapeutic assets by validating CDK4/6 inhibitors as a rescue strategy for drug-resistant tumors.
03

Rare & Neglected Diseases

Mechanistic Modeling & The "Biological Twin"

Overview

We address the scarcity of data in rare tumors by leveraging 'Biological Twins.' Using mechanistic AI to simulate the Tumor Microenvironment (TME), we identify phenotypic convergences with common cancers to repurpose validated therapies.

Key Technologies & Methods

  • The "Biological Twin" Strategy: Overcoming data scarcity by mapping phenotypic overlaps between rare Chordoma and Pancreatic Cancer (PDAC) to accelerate drug repurposing.
  • Ferroptosis Resistance Architecture (ESHG 2026, Gothenburg): Single-cell profiling of 9,157 TBXT⁺ chordoma cells uncovered transcriptional "metabolic lockdown" — a dormant SREBF1-ACSL4 axis (Pearson r=0.017) and extreme GPX4 stoichiometric dominance in 74.9% of tumor cells, with a functionally silent system xc⁻ antiporter. Presented as a poster at the ESHG Congress 2026, this work positions chordoma on a precarious metabolic edge: resistant to conventional ferroptosis inducers at baseline, yet vulnerable if static ER/lipid homeostasis is disrupted.
  • The Inverse Entropy Paradox in Chordoma: Applying our multi-scale entropy profiling package (msep) to sacral chordoma single-cell RNA-seq data reveals tumour cell populations that are individually diverse yet collectively disciplined — a structural signature that single-scale entropy metrics miss entirely.
  • Quadruple-Action Protocol: A systemic attack on the CXCR4 hub to dismantle the tumor's "fortress," simultaneously targeting radioresistance, fibrosis, and immune exclusion.
  • TechBio Integration: Leveraging the TxGemma-27B AI model for mechanistic reasoning to simulate complex WNT5A/TGF-β feedback loops in silico.
  • The "Dual Shield" Hypothesis in Chordoma: A candidate dual immune-escape mechanism in which chordoma combines developmental and microenvironmental defences to evade immune clearance. We map this "dual shield" in silico to identify combination strategies that dismantle both layers — designated for validation in standardized 3D organoid co-cultures.

Please visit our GitHub repository for the execution codes and supplementary materials of our research.

View on GitHub →