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Biology subjects

Wick, L.

Publications and source records attributed to Wick, L..

4 recordsLinked to original sources

Synergistic targeting of EP300/CBP and EYA co-activators collapses the rhabdomyosarcoma core regulatory circuit

Rhabdomyosarcoma (RMS) is a multi-subtype, high-risk pediatric sarcoma with a low mutational burden. The mutations found in RMS often alter genes involved in transcriptional control. Approaches to target dysregulated RMS transcription have remained elusive. Here, we develop a novel approach to target RMS transcription comprising simultaneous targeting of two distinctly acting transcriptional co-activators. We discover a common identity-controlling pan-RMS core regulatory circuit (CRC) composed of oncogenic and lineage-specific myogenic master transcription factors (mTFs). Using a super-enhancer-based reporter screen, we identify the EP300/CBP inhibitor A485 as a potent inhibitor of the pan-RMS CRC, though with efficacy-limiting toxicities. To enhance efficacy, we identify the mTF-binding co-activator EYA2 as a co-factor of this pan-RMS CRC and exploit a new second-generation EYA1/2 inhibitor, LG1-34, to disrupt its function. Combined co-activator inhibition inactivates the CRC and synergistically reduces RMS growth. This strategy dually targets CRC-associated co-activators to cooperatively suppress the RMS transcriptome and enforce cell death.

cancer biology↗

Genetic and Pharmacologic Targeting of Eya3 in Macrophages Drives Anti-Tumor Immunity in Triple-Negative Breast Cancer

Triple negative breast cancer (TNBC) is an aggressive form of breast cancer that remains difficult to treat despite its relatively high immunogenicity, as tumors frequently evade immune destruction through poorly understood mechanisms. Here, we discover a previously unrecognized role for Eya3 within macrophages in the tumor immune microenvironment, where its expression is elevated. Using macrophage Eya3 knockdown and conditional knockout models, we show that Eya3 depletion induces coordinated transcriptional and functional changes in macrophages, enhancing migration, antigen processing, and inflammatory signaling associated with anti-tumor immunity. Strikingly, macrophage-targeted deletion of Eya3 reprograms the immune response in TNBC, increasing CD8+ T cell infiltration, suppressing primary tumor growth, and prolonging survival. Pharmacologic inhibition of Eya3 tyrosine phosphatase activity with a novel allosteric inhibitor, LG1-34, mirrors this effect, dramatically reducing primary TNBC growth through immune-mediated mechanisms that likely act both though targeting tumor and immune cells. These findings identify Eya3 as a macrophage-intrinsic checkpoint on anti-tumor immunity, identifying a new potential vulnerability in TNBC. Significance StatementTargeting Eya3 tyrosine phosphatase activity in tumor-associated macrophages reprograms the TNBC immune microenvironment and restores anti-tumor immunity, identifying a new potential therapeutic vulnerability in a cancer that has limited treatment targeted options.

cancer biology↗

Cryo-EM structures reveal the PP2A-B55α and Eya3 interaction that can be disrupted by a peptide inhibitor

We have previously shown that Eya3 recruits PP2A-B55 to dephosphorylate pT58 on Myc, increasing Myc stability and enhancing primary tumor growth of triple-negative breast cancer (TNBC). However, the molecular details of how Eya3 recruits PP2A-B55 remain unclear. Here we determined the cryo-EM structures of PP2A-B55 bound with Eya3, with an inhibitory peptide B55i, and in its unbound state. These studies demonstrate that Eya3 binds B55 through an extended peptide in the NTD of Eya3. The Eya3 peptide and other PP2A-B55 substrates and protein/peptide inhibitors including B55i bind to a similar area on the B55 surface but the molecular details of the binding differ. We further demonstrated that the B55i peptide inhibits the B55 and Eya3 interaction in vitro. B55i peptide expressed on a plasmid increases pT58 and decreases Myc protein level in TNBC cells, suggesting the potential of B55i or similar peptides as therapies for TNBC.

molecular biology↗

Design and construction of 3D-printed devices to investigate active and passive bacterial dispersal on hydrated surfaces

To disperse in water-unsaturated environments, such as the soil, bacteria rely on the availability and structure of water films forming on biotic and abiotic surfaces, and, especially, along fungal mycelia. Dispersal along such "fungal highways" is driven both by mycelial physical properties and by interactions between bacteria and fungi. To understand the role of abiotic elements, we designed and 3D-printed two devices establishing stable liquid films that support bacteria dispersal in the absence of biotic interactions. The thickness of the liquid film determined the presence of hydraulic flow capable of carrying non-motile cells. In the absence of flow, only motile cells can disperse in the presence of an energy source. Non-motile cells could not disperse autonomously without flow, but dispersed when co-inoculated with motile cells. By teasing apart the abiotic and biotic dimensions, these 3D-printed devices will stimulate further research on microbial dispersal in soil and other water-unsaturated environments.

microbiology↗