Characterisation of DNA-protein crosslink proteolysis repair in cancer therapy with the focus on trapped-PARP1 toxicity
About the research:
DNA-protein crosslinks (DPCs) are under-investigated DNA lesions caused by the covalent attachment of proteins to DNA. DPCs are induced by endogenous aldehydes, chemotherapeutic drugs (such as PARP1 inhibitors) and ionising radiation in hypoxic cells. However, little is known about DPC repair and how do cells acquire resistance to DPC-induced chemo- or radiotherapy. We discovered that the SPRTN metalloprotease is a specialised and essential enzyme for DNA-protein crosslink repair (Lessel et al. Nature Genetics 2014, Vaz et al. Molecular Cell, 2016). Importantly, we have just discovered that SPRTN and its partner - the ATPase p97 - process trapped PARP-1, DPC-like lesion that is essential for therapeutic effect of PARP inhibitors in breast cancer (Krastev et al., Nature Cell Biology, 2021).
Link to Cancer: The enzymes involved in DNA repair are promising druggable targets for cancer therapy. Our discovery of the SPRTN metalloprotease and ATPase p97 as the essential components of DNA repair have been recognised as the promising druggable targets for cancer therapy.
DPhil project aims to characterise SPRTN and p97 enzymatic activities in the context of DNA-protein crosslink repair pathway, with the special focus on trapped-PARP1. You will use standard biochemical and cell biological techniques coupled to state-of-the-art technologies such as CRISPR/Cas9 gene editing, mass-spectrometry and super-resolution microscopy to address your scientific questions. Your work will directly help us to elucidate the mechanism of DNA-protein crosslink proteolysis and trapped-PARP1 (DPC-like lesion) repair in genome stability and how chemical inhibition of the SPRTN protease and/or p97 ATPase could overcome chemotherapy resistance, especially in the context of hypoxic tumours. Here generated knowledge will not only elucidate some basic mechanisms of DNA repair but it will also help us to improve chemotherapy outcome of PARP inhibitors. Finally, your results will be evaluated in a xenograft mouse model.
We have a dynamic and vibrant environment in our laboratories (Ramadan and Giaccia). Our laboratories have expertise in biochemistry, molecular and cell biology, ionizing radiation, hypoxia, and cancer research coupled to the state-of-the-art technologies such as Quantitative Mass-Spectrometry, CRISPR/Cas9 gene editing, Confocal Microscopy, FACS, DNA combing, DNA repair, High-Throughput image analysis and various mouse models. You, as a PhD/DPhil student will get an excellent training in the aforementioned laboratory technologies. The most importantly, once you obtain your PhD/DPhil under our supervision, you will become an independent and competitive scientist on the market. As evident, all our students have so far secured their next-destination jobs at the most prestigious scientific institutions worldwide, such as Oxford, Cambridge, Swiss Federal Institute of Technology (ETH-Zurich), the Curie Institute-Paris or pharma companies. Please check our websites for further details or contact Prof Ramadan directly. Follow us on tweeter: https://twitter.com/Kramadan2
- Dragomir B. Krastev, Shudong Li, Yilun Sun, Andrew Wicks, Gwendoline Hoslett, Daniel Weekes, Luned M. Badder, Eleanor G. Knight, Rebecca Marlow, Mercedes Pardo Calvo4, Lu Yu, Tanaji T. Talele, Jiri Bartek, Jyoti Choudhary, Yves Pommier, Stephen J. Pettitt1*, Andrew N.J. Tutt*, Kristijan Ramadan*, Christopher J. Lord*. The ubiquitin dependent ATPase p97 removes cytotoxic trapped PARP1 from chromatin. Nature Cell Biology, 2021, accepted (*corresponding authors).
- Vaz B, Popovic M, Newman JA, Fielden J, Aitkenhead H, Halder S, Singh AN, Vendrell I, Fischer R, Torrecilla I, Drobnitzky N, Freire R, Amor DJ, Lockhart PJ, Kessler BM, McKenna GW, Gileadi O, Kristijan Ramadan*. Metalloprotease SPRTN/DVC1 Orchestrates Replication-Coupled DNA-Protein Crosslink Repair. Molecular Cell. 2016 Nov 17;64(4):704-719. doi: 10.1016/j.molcel.2016.09.032 (cited 31 times), (*corresponding author).
- Davor Lessel, Bruno Vaz, Swagata Halder… and Janos Terzic*, David J. Amor*, Ivan Dikic*, Kristijan Ramadan*, Christian Kubisch*. Mutations in DVC1/SPRTN cause a syndrome with early-onset hepatocellular carcinoma, genomic instability and progeroid features. Nature Genetics. 2014 Nov;46(11):1239-44. (*corresponding authors).