An interactive resource mapping the proteome and reactive cysteine landscape across the NCI-60 reveals cell and...

The NCI-60 cancer cell line panel is one of the most extensively characterized and publicly accessible resources in cancer research. Here, we expand this platform by generating a comprehensive proteomic and cysteine reactivity atlas using shotgun proteomics and quantitative chemoproteomics. We quantified over 12,000 proteins and identified more than 36,000 reactive cysteines, including over 10,000 hyperreactive sites, across the panel. Our analyses reveal widespread heterogeneity in cysteine reactivity, while conserved hyperreactive cysteines strongly correlate with functional roles. Tissue-specific cysteine reactivity occurred independently of protein abundance, highlighting context-dependent regulation. To enable exploration and integration with existing datasets, we developed an interactive online database that allows users to visualize protein and cysteine coverage and design custom cell line panels. Together, these data and tools illuminate the landscape of cysteine reactivity in cancer and provide a foundational resource to advance future studies in protein function, redox biology, and covalent drug discovery.