Potency and selectivity of a novel pan-RAS inhibitor in 3D bioprinted organoid tumor models

De Nobrega, D. D.; Eiler, L. C.; Ahirwar, P.; Rawal, U. P.; Crawford, C. L.; Buchsbaum, D. J.; Keeton, A. B.; Maxuitenko, Y. Y.; Chen, X.; Piazza, G. A.; Tsung, A.; Budhwani, K. I.

doi:10.1101/2025.02.25.640132

bioRxiv · 10.1101/2025.02.25.640132

Potency and selectivity of a novel pan-RAS inhibitor in 3D bioprinted organoid tumor models

De Nobrega, D. D.·Eiler, L. C.·Ahirwar, P.·Rawal, U. P.·Crawford, C. L.·Buchsbaum, D. J.·Keeton, A. B.·Maxuitenko, Y. Y.·Chen, X.·Piazza, G. A.·Tsung, A.·Budhwani, K. I.

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Abstract

BackgroundColorectal cancer (CRC) remains a significant global health burden, with KRAS mutations driving [~]40% of cases. Efficacy of recently approved, mutant-specific KRAS inhibitors is limited by intrinsic and adaptive resistance mechanisms. Pan-RAS inhibitors, such as ADT-007, offer broader therapeutic potential by targeting multiple RAS isoforms. Here, we evaluate ADT-007 in 3D bioprinted organoid tumors (BOTs) generated from KRAS-mutant and RAS wild-type (WT) CRC cell lines. MethodsPotency and selectivity of ADT-007 were compared to bortezomib, a proteasome inhibitor, and YM155, a survivin inhibitor, using high-content imaging and ATP-based luminescence assays. Mechanistic studies assessed impact on RAS activation and downstream signaling. ResultsADT-007 exhibited high potency and selectivity in KRAS-mutant BOTs, reducing tumor burdens >30% at nanomolar concentrations, and demonstrated superior selectivity over bortezomib and YM155 with minimal cytotoxicity in RAS-WT BOTs. Mechanistic analysis confirmed ADT-007 inhibited RAS activation and downstream signaling, leading to selective apoptosis induction in KRAS-mutant CRC cells. ConclusionsThe selective potency and specificity of ADT-007 warrants further investigation of pan-RAS inhibitors for treating RAS-driven cancers. This study also underscores the translational utility of 3D BOT models for preclinical drug response assessment. Further validation in patient-derived BOTs is necessary to evaluate potential of ADT-007 in clinical settings.

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De Nobrega, D. D., Eiler, L. C., Ahirwar, P., Rawal, U. P., Crawford, C. L., Buchsbaum, D. J., Keeton, A. B., Maxuitenko, Y. Y., Chen, X., Piazza, G. A., Tsung, A., Budhwani, K. I.. 2025-03-01. Potency and selectivity of a novel pan-RAS inhibitor in 3D bioprinted organoid tumor models. https://doi.org/10.1101/2025.02.25.640132

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