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Biology subjects

Schade, A. E.

Publications and source records attributed to Schade, A. E..

2 recordsLinked to original sources

A mechanistic digital twin model for epigenetic therapy optimization in triple-negative breast cancer

Epigenetic therapies offer a promising approach to cancer treatment by modulating chromatin states that govern tumor cell identity, plasticity and therapeutic response. However, predicting and optimizing the effects of such interventions remains challenging. Here, we developed a digital twin framework that integrates mechanistic models of chromatin regulation, in vitro cell-state and treatment response data, and pharmacokinetics to simulate tumor progression and therapeutic response. We applied this framework to triple-negative breast cancer (TNBC), an aggressive disease in which chromatin dysregulation contributes to tumor progression, and investigated combination treatment with an EZH2 inhibitor promiting chromatin opening and an AKT inhibitor, which together enhance expression of GATA3 and BMF. Parameterized and validated using in vitro treatment response data, the model enables in silico clinical trials of alternative combination regimens and treatment schedules. These simulations identify regimens that achieve comparable therapeutic effects to reference schedules while substantially reducing cumulative drug exposure. We further demonstrated the digitan twin's ability of identifying personalized therapeutic strategies by incorporating patient-specific treatment-response data. Our work establishes a mechanistic digital twin framework for predicting tumor responses to chromatin-modifying therapies and provides a quantitative approach for optimizing treatment combinations and schedules across diverse cancer contexts.

cancer biology↗

STRIPAK directs PP2A activity toward MAP4K4 to promote oncogenic transformation

Alterations involving serine-threonine phosphatase PP2A subunits occur in a range of human cancers and partial loss of PP2A function contributes to cell transformation. Displacement of regulatory B subunits by the SV40 Small T antigen (ST) or mutation/deletion of PP2A subunits alters the abundance and types of PP2A complexes in cells, leading to transformation. Here we show that ST not only displaces common PP2A B subunits but also promotes A-C subunit interactions with alternative B subunits (B, striatins) that are components of the Striatin-interacting phosphatase and kinase (STRIPAK) complex. We found that STRN4, a member of STRIPAK, is associated with ST and is required for ST-PP2A-induced cell transformation. ST recruitment of STRIPAK facilitates PP2A-mediated dephosphorylation of MAP4K4 and induces cell transformation through the activation of the Hippo pathway effector YAP1. These observations identify an unanticipated role of MAP4K4 in transformation and show that the STRIPAK complex regulates PP2A specificity and activity.

cancer biology↗