Biology subjects

Patricelli, M. P.

Publications and source records attributed to Patricelli, M. P..

4 recordsLinked to original sources

bioRxiv2026

Allosteric covalent inhibition of cereblon through cryptic cysteine targeting

Thalidomide-derived cereblon (CRBN) modulators are among the most clinically impactful targeted protein degradation therapeutics, redirecting the CRL4-CRBN E3 ubiquitin ligase to degrade disease-driving neosubstrates. All current CRBN-targeting IMiDs and CELMoDs engage a single orthosteric pocket, leaving CRBN's conformational landscape largely unexploited pharmacologically. Using cysteine-directed chemoproteomic screening, we identified covalent ligands that engage Cys287, a cryptic allosteric pocket distal to the orthosteric site. Our lead compound, VVD-105917, acts as a pan-inhibitor of IMiD/CELMoD-driven neosubstrate degradation. Cryo-EM structures reveal that covalent Cys287 engagement traps CRBN in its open, inactive conformation, resolving a previously unobserved N-terminal segment and sensor loop. Sequential incubation experiments show the conformational outcome depends on ligand addition order, demonstrating that even potent CELMoD-driven closure can be overridden by allosteric engagement. A recently reported ligand at this same pocket produces the opposite effect, promoting rather than blocking closure, indicating the Cys287 site is mechanistically sign-switchable. These findings establish covalent chemoproteomics as a strategy for discovering and controlling E3 ligase conformational switches.

biochemistry↗

bioRxiv2024

Covalent inhibitors of the RAS binding domain of PI3Ka impair tumor growth driven by RAS and HER2

Genetic disruption of the RAS binding domain (RBD) of PI 3-kinase (PI3K) prevents the growth of mutant RAS driven tumors in mice and does not impact PI3Ks role in insulin mediated control of glucose homeostasis. Selectively blocking the RAS-PI3K interaction may represent an attractive strategy for treating RAS-dependent cancers as it would avoid the toxicity associated with inhibitors of PI3K lipid kinase activity such as alpelisib. Here we report compounds that bind covalently to cysteine 242 in the RBD of PI3K p110 and block the ability of RAS to activate PI3K activity. These inhibitors have a profound impact on the growth of RAS mutant and also HER2 over-expressing tumors, particularly when combined with other inhibitors of the RAS/MAPK pathway, without causing hyperglycemia.

cancer biology↗

bioRxiv2024

Suppression of NRF2-dependent cancer growth by a covalent allosteric molecular glue

The NRF2 transcription factor is constitutively active in cancer where it functions to maintain oxidative homeostasis and reprogram cellular metabolism. NRF2-active tumors exhibit NRF2-dependency and resistance to chemo/radiotherapy. Here we characterize VVD-065, a first-in-class NRF2 inhibitor that acts via an unprecedented allosteric molecular glue mechanism. In the absence of stress or mutation, NRF2 is rapidly degraded by the KEAP1-CUL3 ubiquitin-ligase complex. VVD-065 specifically and covalently engages C151 on KEAP1, which in turn promotes KEAP1-CUL3 complex formation, leading to enhancement of NRF2 degradation. Previously reported C151-directed compounds decrease KEAP1-CUL3 interactions and stabilize NRF2, thus establishing KEAP1_C151 as a tunable regulator of the KEAP1-CUL3 complex and NRF2 stability. VVD-065 inhibited NRF2-dependent tumor growth and sensitized cancers to chemo/radiotherapy, supporting an open Phase I clinical trial (NCT05954312).

cancer biology↗

bioRxiv2022

Selective inhibitors of JAK1 targeting a subtype-restricted allosteric cysteine

The JAK family of non-receptor tyrosine kinases includes four subtypes (JAK1, JAK2, JAK3, and TYK2) and is responsible for signal transduction downstream of diverse cytokine receptors. JAK inhibitors have emerged as important therapies for immuno(onc)ological disorders, but their use is limited by undesirable side effects presumed to arise from poor subtype selectivity, a common challenge for inhibitors targeting the ATP-binding pocket of kinases. Here, we describe the chemical proteomic discovery of a druggable allosteric cysteine present in the non-catalytic pseudokinase domain of JAK1 (C817) and TYK2 (C838), but absent from JAK2 or JAK3. Electrophilic compounds selectively engaging this site block JAK1-dependent transphosphorylation and cytokine signaling, while appearing to act largely as "silent" ligands for TYK2. Importantly, the allosteric JAK1 inhibitors do not impair JAK2-dependent cytokine signaling and are inactive in cells expressing a C817A JAK1 mutant. Our findings thus reveal an allosteric approach for inhibiting JAK1 with unprecedented subtype selectivity.

pharmacology and toxicology↗