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Biology subjects

Lill, J. R.

Publications and source records attributed to Lill, J. R..

3 recordsLinked to original sources

TEAD-targeting small molecules induce a cofactor switch to regulate the Hippo pathway

TEAD proteins are the main transcriptional effectors of the Hippo signaling pathway and a pharmacological target in oncology. Most TEAD-targeting small molecules act by disrupting interaction with the oncogenic transcriptional activators YAP and TAZ. Here, we describe an alternative mechanism for TEAD lipid pocket binding molecules. We report that select sulfonamide-containing compounds promote TEAD interaction with the transcriptional repressor VGLL4 to induce a small molecule-mediated cofactor switch from YAP to VGLL4. Chemically induced VGLL4-TEAD complexes counteract YAP activity at chromatin to repress pro-growth gene networks, including genes involved in cellular proliferation and mechanosignaling. VGLL4 is required for an anti-proliferative response to these select compounds, and genetic deletion of VGLL4 causes resistance to these molecules in vitro and in vivo. Our data reveal a category of molecules that facilitate the repressive VGLL4-TEAD interaction and open up new understandings for curbing the oncogenic activity of Hippo pathway deregulation.

cancer biology↗

Targeting the Hippo pathway in cancers via ubiquitination dependent TEAD degradation

The Hippo pathway is among the most frequently altered key signaling pathways in cancer. TEAD1-4 are essential transcription factors and key downstream effectors in the Hippo pathway in human cells. Here, we identified RNF146 as a ubiquitin ligase (E3) of TEADs, which negatively regulates their stability in cells through proteasome-mediated degradation. We show that RNF146-mediated TEAD ubiquitination is dependent on the TEAD PARylation state. We further validated the genetic interaction between RNF146 and the Hippo pathway in cancer cell lines and the model organism Drosophila melanogaster. Despite the RNF146 and proteasome-mediated degradation mechanisms, TEADs are stable proteins with a long half-life in cells. We demonstrate that degradation of TEADs can be greatly enhanced pharmacologically with heterobifunctional chemical inducers of protein degradation (CIDEs). These TEAD-CIDEs can effectively suppress activation of YAP/TAZ target genes in a dose-dependent manner and exhibit significant anti-proliferative effects in YAP/TAZ-dependent tumor cells, thus phenocopying the effect of genetic ablation of TEAD protein. Collectively, this study demonstrates that the ubiquitin-proteasome system plays an important role in regulating TEAD functions and provides a proof-of-concept demonstration that pharmacologically induced TEAD ubiquitination could be leveraged to target YAP/TAZ-driven cancers.

cancer biology↗

Sensitive and quantitative detection of MHC-I displayed neoepitopes using a semi-automated workflow and TOMAHAQ mass spectrometry

Advances in several key technologies, including MHC peptidomics, has helped fuel our understanding of basic immune regulatory mechanisms and identify T cell receptor targets for the development of immunotherapeutics. Isolating and accurately quantifying MHC-bound peptides from cells and tissues enables characterization of dynamic changes in the ligandome due to cellular perturbations. This multi-step analytical process remains challenging, and throughput and reproducibility are paramount for rapidly characterizing multiple conditions in parallel. Here, we describe a robust and quantitative method whereby peptides derived from MHC-I complexes from a variety of cell lines, including challenging adherent lines, can be enriched in a semi-automated fashion on reusable, dry-storage, customized antibody cartridges. TOMAHAQ, a targeted mass spectrometry technique that combines sample multiplexing and high sensitivity, was employed to characterize neoepitopes displayed on MHC-I by tumor cells and to quantitatively assess the influence of neoantigen expression and induced degradation on neoepitope presentation.

cancer biology↗