Decoding and controlling cell-state switching: A bottom-up approach based on enhancer logic

ended

Cell-state switching in cancer allows cells to transition from a proliferative to an invasive and drug-resistant phenotype. This plasticity plays an important role in cancer progression and tumour heterogeneity. We have made a striking observation that cancer cells of different origin can switch to a common survival state. During this epigenomic reprogramming, cancer cells re-activate genomic enhancers from specific regulatory programs, such as wound repair and epithelial-to-mesenchymal transition. The goal of my project is to decipher the enhancer logic underlying this canalization effect towards a common survival state. We will then employ this new understanding of enhancer logic to engineer synthetic enhancers that are able to monitor and manipulate cell-state switching in real time. Furthermore, we will use enhancer models to identify cis-regulatory mutations that have an impact on cell-state switching and drug resistance. Such applications are currently hampered because there is a significant gap in our understanding of how enhancers work. To tackle this problem we will use a combination of in vivo massively parallel enhancer-reporter assays, single-cell genomics on microfluidic devices, computational modelling, and synthetic enhancer design. Using these approaches we will pursue the following aims: (1) to identify functional enhancers regulating cell-state switching by performing in vivo genetic screens in mice; (2) to elucidate the dynamic trajectories whereby cells of different cancer types switch to a common survival cell-state, at single-cell resolution; (3) to create synthetic enhancer circuits that specifically kill cancer cells undergoing cell-state switching. Our findings will have an impact on genome research, characterizing how cellular decision making is implemented by the cis-regulatory code; and on cancer research, employing enhancer logic in the context of cancer therapy.