Abstract 1331: The Kinase Library: A global atlas of the human protein kinome and its applications in cancer.

Abstract Mass-spectrometry-based phosphoproteomics now profiles phosphorylation at proteome scale, yet converting site-level measurements into coherent, kinase-centered biology remains a persistent barrier to interpretation and action. The Kinase Library addresses this gap with the first-in-class, unbiased, experimentally characterized motif atlas of the human kinome, coupled to enrichment frameworks that translate phosphoproteomics data into quantitative maps of kinase activity. Rather than relying on heterogeneous annotations or heuristic rules, KL grounds inference in experimentally derived kinase-substrate relationships, providing a principled basis for comparative signaling analysis. The Kinase Library has broad utility across discovery and translational applications. It enables mechanism-of-action profiling for small molecules and combinations; delineates adaptive signaling and resistance trajectories; supports time-course and dose-response studies to resolve pathway dynamics; and stratifies models and patients in low-N-high-D (few samples with high dimensionality of data) settings where conventional statistics underperform. In clinical and preclinical contexts alike — cell lines, organoids, xenografts, and patient specimens — the Kinase Library delivers harmonized, interpretable kinase signatures that are readily integrated with genomic, transcriptomic, and phenotypic readouts to generate and prioritize actionable hypotheses. The novelty of the Kinase Library is twofold. First, scope and provenance: an experimental, unbaised atlas spanning the entire kinome, with comprehensive inclusion of the dark kinome. Second, operationalization: a unified enrichment paradigm that yields robust, rank-ordered kinase programs suitable for decisionmaking — whether the objective is target nomination, combination design, biomarker discovery, or comparative benchmarking across cohorts and studies. Looking forward, the Kinase Library is positioned to empower emerging frontiers in proteomics: single-cell and spatial phosphoproteomics; longitudinal “N-of-1” monitoring to guide therapy; cross-species translation for model selection; and cloudnative workflows that interoperate with community pipelines and public datasets. By elevating kinases from disparate lists of regulated sites to coherent, testable signaling hypotheses, the Kinase Library reframes what phosphoproteomics can deliver — shifting the field from descriptive measurement toward predictive, mechanism-guided intervention. Citation Format: Tomer M. Yaron-Barir, Jared L. Johnson, Benjamin E. Turk, Michael B. Yaffe, Lewis C. Cantley. The Kinase Library: A global atlas of the human protein kinome and its applications in cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1331.